BioRxiv – open access preprints

si-bioRxiv

For the vast majority of the general population, science is consumed via mass media head lines and carefully edited summaries of the research.

The result of this simplified end product is an ignorance of the process that researchers need to deal with in order to get their research in the public domain.

As part of our efforts to educate the general public about the scientific research of Parkinson’s disease, it is necessary to also make them aware of that process, the issues associated with it, and how it is changing over time.

In todays post, we will look at how new research reports are being made available to the public domain before they are published.


ibiology-preprints-1024x576

Getting research into the public domain. Source: STAT

Every morning here at the SoPD, we look at what new research has entered the public domain over night and try to highlight some of the Parkinson’s disease relevant bits on our Twitter account (@ScienceofPD).

To the frustration of many of our followers, however, much of that research sits behind the pay-to-view walls of big publishing houses. One is allowed to read the abstract of the research report in most cases, but not the full report.

Given that charity money and tax payer dollars are paying for much of the research being conducted, and for the publication fee (approx. $1500 per report on average) to get the report into the journal, there is little debate as to the lack of public good in such a system. To make matter worse, many of the scientists doing the research can not access the published research reports, because their universities and research institutes can not afford the hefty access fees for all of the journals.

Problem-infographic3

Source: Libguides

To be fair, the large publishing houses have recognised that this is not a sustainable business model, and they have put forward the development of open-access web-based science journals, such as Nature communications, Scientific reports, and Cell reports. But the fees for publishing in these journals can in some cases be higher than the closed access publications.

This is crazy. What can we do about it?

Well, there have been efforts for some time to improve the situation.

Projects like the Public Library of Science (or PLOS) have been very popular and are now becoming a real force on the scientific publishing landscape (they recently celebrated their 10 year anniversary and during that time they have published more than 165,000 research articles). But they too have costs associated with maintaining their service and publications fees can still be significant.

url

Is there an easier way of making this research available?

So this is Prof Paul Ginsparg.

Ginsparg_at_Cornell_University

Source: Wikipedia

Looks like the mad scientist type right? Don’t be fooled. He’s awesome! Prof Ginsparg is a professor of Physics and Computing & Information Science at Cornell University.

Back in 1991, he started a repository of pre-print publications in the field of physics. The repository was named arXiv.org, and it allowed physics researchers to share and comment on each others research reports before they were actually published.

The site slowly became an overnight sensation.

The number of manuscripts deposited at arXiv passed the half-million mark on October 3, 2008, the million manuscript mark by the end of 2014 (with a submission rate of more than 8,000 manuscripts per month). The site currently has 1,257,315 manuscripts that are freely available to access. A future nobel prize winning bit of research is probably in there!

Now, by their very nature, and in a very general sense, biomedical researchers are a jealous bunch.

For many years they looked on with envy at the hive of activity going on at arXiv and wished that they had something like it themselves. And now they do! In November 2013, Cold Spring Harbor Laboratory in New York launched BioRxiv.

maxresdefault

Source: BioRxiv

And the website is very quickly becoming a popular destination: by April 21, 2017, >10,000 manuscript had been posted, at a current rate of over 800 manuscripts per month (Source).

Recently they got a huge nod of financial support from the Chan Zuckerberg Initiative – a foundation set up by Facebook founder Mark Zuckerberg and his wife Priscilla Chan to “advance human potential and promote equality in areas such as health, education, scientific research and energy” (Wikipedia).

5677ff2b-be2c-49e7-b0cb-7e33c18149dd-1467045359144Chan-Zuckerberg-Initiative-1

Source: ChangZuckerberg

In April of this year, the Chan Zuckerberg Initiative announced a partnership with Cold Spring Harbor Laboratory to help support the site (Click here to see the press release).

So what is bioRxiv?

bioRxiv is a free OPEN ACCESS service that allows researchers to submit draft copies of scientific papers — called preprints — for their colleagues to read and comment on before they are actually published in peer-reviewed scientific journals.

Here are two videos explaining the idea:

Sounds great right?

To demonstrate how the bioRxiv process works, we have selected an interesting manuscript from the database that we would like to review here on the SoPD.

This is the article:

HEMMER

Title: In Vivo Phenotyping Of Parkinson-Specific Stem Cells Reveals Increased a-Synuclein Levels But No Spreading
Authors: Hemmer K, Smits LM, Bolognin S, Schwamborn JC
Database: BioRxiv
DOI: https://doi.org/10.1101/140178
PMID: N/A                   (You can access the manuscript by clicking here)

In this study (which was posted on bioRxiv on the 19th May, 2017), the researchers have acquired skin cells from an 81 year old female with Parkinson’s disease who carries a mutation (G2019S) in the LRRK2 gene.

Mutations in the Leucine-rich repeat kinase 2 (or Lrrk2) gene are associated with an increased risk of developing Parkinson’s disease. The most common mutation of LRRK2 gene is G2019S, which is present in 5–6% of all familial cases of Parkinson’s disease, and is also present in 1–2% of all sporadic cases. We have previously discussed Lrrk2 (Click here to read that post).

image1

The structure of Lrrk2 and where various mutations lie. Source: Intech

The skin cells were transformed using a bit of biological magic in induced pluripotent stem (or IPS) cells. We have previously discussed IPS cells and how they are created (Click here to read that post). By changing a subjects skin cell into a stem cell, researchers can grow the cell into any type of cell and then investigate a particular disease on a very individualised basis (the future of personalised medicine don’t you know).

nature10761-f2.2

IPS cell options available to Parkinson’s disease. Source: Nature

Using this IPS cell with a mutation in the LRRK2 gene, the researchers behind todays manuscript next grew the cells in culture and encouraged the cells to become dopamine producing cells (these are some of the most vulnerable cells in Parkinson’s disease). The investigators had previously shown that neurons grown in culture from cells with the G2019S mutation in the LRRK2 gene have elevated levels of of the Parkinson’s disease protein alpha Synuclein (Click here to read that OPEN ACCESS paper).

In this present study, the investigators wanted to know if these cells would also have elevated levels of alpha synuclein when transplanted into the brain. Their results indicate that the cells did. Next, the investigators wanted to use this transplantation model to see if the high levels of alpha synuclein in the transplanted cells would lead to the protein being passed to neighbouring cells.

Why did they want to do that?

One of the current theories regarding the mechanisms underlying the progressive spread of Parkinson’s disease is that the protein alpha synuclein is lead culprit. Under normal conditions, alpha synuclein usually floats around as an individual protein (or monomer), but sometime it starts to cluster (or aggregate) with other monomers of alpha synuclein and these form what we call oligomers. These oligomers are believed to be a toxic form of alpha synuclein that is being passed from cell to cell. And it ‘seeds’ the disease in each cell it is passed on to (Click here for a very good OPEN ACCESS review of this topic).

Mechanism of syunuclein propagation and fibrillization

The passing of alpha synuclein between brain cells. Source: Nature

There have been postmortem analysis studies of the brains from people with Parkinson’s who have had cell transplantation therapy back in the 1990s. The analysis shows that some of the transplanted cells have evidence of toxic alpha synuclein in them – some of those cells have Lewy bodies in them, suggesting that the disease has been passed on to the healthy introduced cells from the diseased brain (Click here for the OPEN ACCESS research report about this).

In the current bioRxiv study, the investigators wanted to ask the reverse question:

Can unhealthy, toxic alpha synuclein producing cells cause the disease to spread into a healthy brain?

So after transplanted the Lrrk2 mutant cells into the brains of mice, they waited 11 weeks to see if the alpha synuclein would be passed on to the surrounding brain. According to their results, the unhealthy alpha synuclein did not transfer. They found no increase in levels of alpha synuclein in the cells surrounding the transplanted cells. The researchers concluded that within the parameters of their experiment, Parkinson’s disease-associated alpha synuclein spreading was not detected.

Interesting. When will this manuscript be published in a scientific journal?

We have no idea.

One sad truth of the old system of publication is: it may never be.

And this illustrates one of the beautiful features of bioRxiv.

This manuscript is probably going through the peer-review process at a particular scientific journal at the moment in order for it to be properly published. It is a process that will take several months. Independent reviewers will provide a critique of the work and either agree that it is ready for publication, suggest improvements that should be made before it can be published, or reject it outright due to possible flaws or general lack of impact (depending on the calibre of the journal – the big journals seem to only want sexy science). It is a brutal procedure and some manuscripts never actually survive it to get published, thus depriving the world of what should be freely available research results.

And this is where bioRxiv provides us with a useful forum to present scientific biological research that may never reach publication. Perhaps the researchers never actually intended to publish their findings, and just wanted to let the world know that someone had attempted the experiment and these are the results they got (there is a terrible bias in the world of research publishing to only publish positive results).

The point is: with bioRxiv we can have free access to the research before it is published and we do not have to wait for the slow peer-review process.

And there is definitely some public good in that.

EDITORS NOTE HERE: We are not suggesting for a second that the peer-review process should be done away with. The peer-review process is an essential and necessary aspect of scientific research, which helps to limit fraud and inaccuracies in the science being conducted.

What does it all mean?

This post may be boring for some of our regular readers, but it is important for everyone to understand that there are powerful forces at work in the background of scientific research that will determine the future of how information is disseminated to both the research community and general population. It is useful to be aware of these changes.

We hope that some of our readers will be bold/adventurous and have a look at some of what is on offer in the BioRxiv database. Maybe not now, but in the future. It will hopefully become a tremendous resource.

And we certainly encourage fellow researchers to use it (most of the big journals now accept preprint manuscripts being made available on sites like bioRxiv – click here to see a list of the journals that accept this practise) and some journals also allow authors to submit their manuscript directly to a journal’s submission system through bioRxiv via the bioRxiv to Journals (B2J) initiative (Click here for a list of the journals accepting this practise).

The times they are a changing…


The banner for today’s post was sourced from ScienceMag

Are Dyskinesias days NAM-bered?

header

Addex Therapeutics and the Michael J Fox Foundation are preparing to initiate a new clinical trial testing a new drug called Dipraglurant on levodopa-induced dyskinesia (Source).

Dipraglurant is a mGluR5 negative allosteric modulator (don’t panic, it’s not as complicated as it sounds).

In today’s post, we’ll explain what all of that means and look at the science behind this new treatment.


Dysco

An example of a person with dyskinesia. Source: JAMA Neurology

For anyone familiar with Parkinson’s disease, they will know that long term use of the treatment L-dopa can lead to two possible outcomes:

  1. The treatment loses it’s impact, requiring ever higher doses to be administered
  2. The appearance of dykinesias

Now, not everyone taking L-dopa will be affected by both of these outcomes, but people with young, onset Parkinson’s disease do seem to be at risk of developing L-dopa induced dykinesias.

What are Dyskinesias?

Dyskinesias (from Greek: dys – abnormal; and kinēsis – motion, movement) are simply a category of movement disorders that are characterised by involuntary muscle movements. And they are certainly not specific to Parkinson’s disease.

As we have suggested above, they are associated in Parkinson’s disease with long-term use of L-dopa.

Below is a video of two legends: the late Tom Isaacs (who co-founded the Cure Parkinson’s Trust) and David Sangster (he founded www.1in20Parkinsons.org.uk). They were both diagnosed with Parkinson’s disease in their late 20’s. Tom, having lived with Parkinson’s for 20 years at the time of this video provides a good example of what dyskinesias look like:

https://www.youtube.com/watch?v=LLu3Yn__hrY

As you can see, dyskinesias are a debilitating issue for anyone who suffers them.

How do dyskinesias develop in Parkinson’s disease?

Before being diagnosed and beginning a course of L-dopa, the locomotion parts of the brain in a person with Parkinson’s disease gradually becomes more and more inhibited. This increasing inhibition results in the slowness and difficulty in initiating movement that characterises this condition. A person with Parkinson’s may want to move, but they can’t.

They are akinetic (from Greek: a-, not, without; and kinēsis – motion).

972px-Paralysis_agitans_(1907,_after_St._Leger)

Drawing of an akinetic individual with Parkinson’s disease, by Sir William Richard Gowers
Source: Wikipedia

L-dopa tablets provide the brain with the precursor to the chemical dopamine. Dopamine producing cells are lost in Parkinson’s disease, so replacing the missing dopamine is one way to treat the motor features of the condition. Simply giving people pills of dopamine is a non-starter: dopamine is unstable, breaks down too quickly, and (strangely) has a very hard time getting into the brain. L-dopa, on the other hand, is very robust and has no problem getting into the brain.

7001127301-6010801

Sinemet is L-dopa. Source: Drugs

Once inside the brain, L-dopa is quickly converted into dopamine. It is changed into dopamine by an enzyme called DOPA decarboxylase, and this change rapidly increases the levels of dopamine in the brain, allowing the locomotion parts of the brain to function more normally.

4INJ4aV

The chemical conversion of L-dopa to dopamine. Source: Nootrobox

In understanding this process, it is important to appreciate that when an L-dopa tablet is consumed and L-dopa enters the brain, there is a rapid increase in the levels of dopamine. A ‘spike’ in the supply of dopamine, if you will, and this will last for the next few hours, before the dopamine is used up.

As the effects of the L-dopa tablet wear off, another tablet will be required. This use of multiple L-dopa pills across the day gives rise to a wave-like shape to the dopamine levels in the brain over the course of the day (see the figure below). The first pill in the morning will quickly lift the levels of dopamine enough that the individual will no longer feel akinetic. This will allow them to be able to function with normal controlled movement for several hours before the L-dopa begins to wear off. As the L-dopa wears off, the dopamine levels in the brain drop back towards levels that will leave the person feeling akinetic and at this point another L-dopa tablet is required.

Dysk1

After several years of L-dopa use, many people with Parkinson’s disease will experience a weaker response to each tablet. They will also find that they have more time during which they will be unable to move (exhibiting akinesia). This is simply the result of the progression of Parkinson’s disease – L-dopa treats the motor features of the disease but only hides/masks the fact that the disease is still progressing.

To combat this shorter response time, the dose of L-dopa is increased. This will result in increasing levels of dopamine in the brain (as illustrated by the higher wave form over time in the image below). It will take more L-dopa medication induced dopamine to lift the individual out of the akinetic state.

Dyskinesias3

This increasing of L-dopa dosage, however, is often associated with the gradual development of abnormal involuntary movements that appear when the levels of L-dopa induced dopamine are the highest.

These are the dyskinesias.

Are there different types of dyskinesias?

Yes there are.

Dyskinesias have been broken down into many different subtypes, but the two main types of dyskinesia are:

Chorea – these are involuntary, irregular, purposeless, and unsustained movements. To an observer, Chorea will look like a very disorganised/uncoordinated attempt at dancing (hence the name, from the Greek word ‘χορεία’ which means ‘dance’). While the overall activity of the body can appear continuous, the individual movements are brief, infrequent and isolated. Chorea can cause problems with maintaining a sustained muscle contraction,  which may result in affected people dropping things or even falling over.

Dystonia – these are sustained muscle contractions. They often occur at rest and can be either focal or generalized. Focal dystonias are involuntary contractions in a single body part, for example the upper facial area. Generalized dystonia, as the name suggests, are contraction affecting multiple body regions at the same time, typically the trunk, one or both legs, and another body part. The intensity of muscular movements in sufferers can fluctuate, and symptoms usually worsen during periods of fatigue or stress.

We have previously discussed the current treatment options for dyskinesias (click here to see that post).

Ok, so what clinical trials are Addex Therapeutics and the Michael J Fox Foundation preparing and why?

They are preparing to take a drug called Dipraglurant through phase III testing for L-dopa inducing dyskinesias in Parkinson’s disease. Dipraglurant is a mGluR5 negative allosteric modulator.

And yes, I know what you are going to ask next: what does any of that mean?

Ok, so mGluR5 (or Metabotropic glutamate receptor 5) is a G protein-coupled receptor. This is a structure that sits in the skin of a cell (the cell membrane), with one part exposed to the outside world – waiting for a chemical to bind to it – while another part is inside the cell, ready to act when the outside part is activated. The outside part of the structure is called the receptor.

Metabotropic receptors are a type of receptor that is indirectly linked with channels in cell membrane. These channels open and close, allowing specific elements to enter the cell. When a chemical (or agonist) binds to the receptor and it becomes activated, the part of the structure inside the cell will send a signal to the channel via a messenger (called a G-protein).

The chemical that binds to mGluR5 is the neurotransmitter glutamate.

U4.cp2.1_nature01307-f1.2

Metabotropic glutamate receptor 5 activation. Source: Nature

But what about the “negative allosteric modulator” part of ‘mGluR5 negative allosteric modulator’

Good question.

This is the key part of this new approach. Allosteric modulators are a new class of orally available small molecule therapeutic agents. Traditionally, most marketed drugs bind directly to the same part of receptors that the body’s own natural occurring proteins attach to. But this means that those drugs are competing with those endogenous proteins, and this can limit the potential effect of the drug.

Allosteric modulators get around this problem by binding to a different parts of the receptor. And instead of simply turning on or off the receptor, allosteric modulators can either turn up the volume of the signal being sent by the receptor or decrease the signals. This means that when the body’s naturally occurring protein binds in the receptor, allosteric modulators can either amplify the effect or reduce it depending on which type of allosteric modulators is being administered.

allosteric_modulation_mechanism

How Allosteric modulators work. Source: Addrex Thereapeutics

There are two different types of allosteric modulators: positive and negative. And as the label suggests, positive allosteric modulators (or PAMs) increase the signal from the receptor while negative allosteric modulators (or NAMs) reduce the signal.

So Dipraglurant turns down the volume of the signal from the mGluR5 receptor?

Exactly.

By turning down the volume of the glutamate receptor mGluR5, researchers believe that we can reduce the severity of dyskinesias.

But hang on a second. Why are we looking at glutamate in dyskinesias? Isn’t dopamine the chemical of interest in Parkinson’s disease?

So almost 10 years ago, some researchers noticed something interesting in the brains of Parkinsonian monkeys that had developed dyskinesias:

Monkey2
Title: mGluR5 metabotropic glutamate receptors and dyskinesias in MPTP monkeys.
Authors: Samadi P, Grégoire L, Morissette M, Calon F, Hadj Tahar A, Dridi M, Belanger N, Meltzer LT, Bédard PJ, Di Paolo T.
Journal: Neurobiol Aging. 2008 Jul;29(7):1040-51.
PMID: 17353071

The researchers conducting this study induced Parkinson’s disease in monkeys using a neurotoxin called MPTP, and they then treated the monkeys with L-dopa until they began to develop dyskinesias. At this point when they looked in the brains of these monkeys, the researchers noticed a significant increase in the levels of mGluR5, which was associated with the dyskinesias. This finding led the researchers to speculate that reducing mGluR5 levels might reduce dyskinesias.

And it did!

Subsequent preclinical research indicated that targeting mGluR5 might be useful in treating dyskinesias, especially with negative allosteric modulators:

Monkey
Title: The mGluR5 negative allosteric modulator dipraglurant reduces dyskinesia in the MPTP macaque model
Authors: Bezard E, Pioli EY, Li Q, Girard F, Mutel V, Keywood C, Tison F, Rascol O, Poli SM.
Journal: Mov Disord. 2014 Jul;29(8):1074-9.
PMID: 24865335

In this study, the researchers tested the efficacy of dipraglurant in Parkinsonian primates  that had developed L-dopa induced dyskinesias. They tested three different doses of the drug (3, 10, and 30 mg/kg).

Dipraglurant significantly reduced dyskinesias in the monkeys, with best effect being reached using the 30 mg/kg dose. Importantly, the dipraglurant treatment had no impact on the efficacy of L-dopa which was still being used to treat the monkeys Parkinson’s features.

This research lead to a clinical trials in man, and last year Addex Therapeutics published the results of their phase IIa clinical trial of Dipraglurant (also called ADX-48621):

NAM

Title: A Phase 2A Trial of the Novel mGluR5-Negative Allosteric Modulator Dipraglurant for Levodopa-Induced Dyskinesia in Parkinson’s Disease.
Authors: Tison F, Keywood C, Wakefield M, Durif F, Corvol JC, Eggert K, Lew M, Isaacson S, Bezard E, Poli SM, Goetz CG, Trenkwalder C, Rascol O.
Journal: Mov Disord. 2016 Sep;31(9):1373-80.
PMID: 27214664

The Phase IIa double-blind, placebo-controlled, randomised trial was a dose escalation study, conducted in 76 patients with Parkinson’s disease L-dopa-induced dyskinesia – 52 subjects were given dipraglurant and 24 received a placebo treatment. The dose escalation assessment of dipraglurant started at 50 mg once daily to 100 mg 3 times daily. The study was conducted over 4 weeks.

The investigators found that dipraglurant significantly reduced the dyskinesias on both day 1 of the study and on day 14, and this treatment did not result in any worsening of the Parkinsonian features. And remember that this was a double blind study, so both the investigators and the participants had no idea which treatment was being given to each subject. Thus little bias can influence the outcome, indicating that dipraglurant really is having a beneficial effect on dyskinesias.

The company suggested that dipraglurant’s efficacy in reducing L-dopa-induced dyskinesia warrants further investigations in a larger number of patients. And this is what the company is now doing with the help of the Michael J. Fox Foundation (MJFF). In addition, dipraglurant’s potential benefits on dystonia are also going to be investigated with support from the Dystonia Medical Research Foundation (DMRF).

And the really encouraging aspect of this research is that Addex Therapeutics are not the only research group achieving significant beneficial results for dykinesias using this treatment approach (click here to read about other NAM-based clinical studies for dyskinesias).

Fingers crossed for more positive results here.

What happens next?

L-dopa induced dyskinesias can be one of the most debilitating aspects of living with Parkinson’s disease, particularly for the early-onset forms of the condition. A great deal of research is being conducted in order to alleviate these complications, and we are now starting to see positive clinical results starting to flow from that research.

These results are using new type of therapeutic drug that are designed to increase or decrease the level of a signal occurring in a cell without interfering with the normal functioning of the chemicals controlling the activation of that signal.

This is really impressive biology.


The banner for today’s post was sourced from Steam

The Melanoma drug from MODAG

Melanoma

A build up of a protein called alpha synuclein inside neurons is one of the characteristic feature of the Parkinsonian brain. This protein is believed to be partly responsible for the loss of dopamine neurons in this condition.

A similar build up of alpha synuclein is also seen in the deadly skin cancer, Melanoma… but those cells don’t die (?!?)… in fact, they just keep on dividing.

Why is there this critical difference?

In today’s post we look at an interesting new study that may have solved this mystery.


o-melanoma-facebook

A melanoma. Source: Huffington Post

Parkinson’s disease has a very strange relationship with the skin cancer melanoma.

As we have stated in previous posts (Click here, herehere and here to read those posts) people with Parkinson’s disease are 2-8 times more likely to develop melanoma than people without Parkinson’s (And this finding has been replicated a few times: Olsen et al, 2005; Olsen et al, 2006; Driver et al 2007; Gao et al 2009; Lo et al 2010; Bertoni et al 2010;Schwid et al 2010; Ferreira et al, 2010Inzelberg et al, 2011; Liu et al 2011; Kareus et al 2012; Wirdefeldt et al 2014; Catalá-López et al 2014; Constantinescu et al 2014; Ong et al 2014).

The truly baffling detail in this story, however, is that this relationship is reciprocal – if you have melanoma you are almost 3 times more likely to develop Parkinson’s disease than someone without melanoma (Source: Baade et al 2007; Gao et al 2009).

What is melanoma exactly?

Melanoma is a type of skin cancer.

It develops from the pigment-containing cells known as melanocytes. Melanocytes are melanin-producing cells located in the bottom layer (the stratum basale) of the skin’s outer layer (or epidermis).

Blausen_0632_Melanocyte

The location of melanocytes in the skin. Source: Wikipedia

Melanocytes produce melanin, which is a pigment found in the skin, eyes, and hair. It is also found in the brain in certain types of cells, such as dopamine neurons (where it is referred to as neuromelanin).

subnigmicro

Neuromelanin (brown) in dopamine neurons. Source: Schatz

Melanomas are usually caused by DNA damage resulting from exposure to ultraviolet radiation. Ultraviolet radiation from tanning beds increases the risk of melanoma (Source), as does excessive air travel (Source), or simply spending to much time sun bathing.

Approximately 2.2% of men and women will be diagnosed with melanoma at some point during their lives (Source). In women, melanomas most commonly occur on the legs, while in men they are most common on the back. Melanoma makes up 5% of all cancers (Source).

Generally, melanomas is one of the safer cancers, as it can usually be detected early by visual inspection. This cancer is made dangerous, however, by its ability to metastasise (or spread to other organs in the body).

melanoma-progression

The stages of melanoma. Source: Pathophys

Are there any genetic associations between Parkinson’s disease and melanoma?

No.

When the common genetics mutations that increase the risk of both conditions were previously analysed, it was apparent that none of the known Parkinson’s mutations make someone more susceptible to melanoma, and likewise none of the melanoma-associated genetic mutations make a person vulnerable to Parkinson’s disease (Meng et al 2012;Dong et al 2014; Elincx-Benizri et al 2014).

In fact, researchers have only found very weak genetic connections between two conditions (Click here to read our previous post on this). It’s a real mystery.

Are there any other connections between Parkinson’s disease and melanoma?

Yes.

Another shared feature of both Parkinson’s disease and melanoma is the build up of a protein called alpha synuclein. Alpha synuclein is believed to be one of the villains in Parkinson’s disease – building up inside a cell, becoming toxic, and eventually killing that cell.

But recently researchers noticed that melanoma also has a build up of alpha synuclein, but those cells don’t die:

Melan2

Title: Parkinson’s disease-related protein, alpha-synuclein, in malignant melanoma
Authors: Matsuo Y, Kamitani T.
Journal: PLoS One. 2010 May 5;5(5):e10481.
PMID: 20463956               (This article is OPEN ACCESS if you would like to read it)

In this study, researchers from Japan found that alpha synuclein was detected in 86% of the primary and 85% of the metastatic melanoma. Understand that the protein is not detectable in the non-melanoma cancer cells.

So what is it doing in melanoma cells?

Recently, researchers from Germany believe that they have found the answer to this question:

Melanoma

Title: Treatment with diphenyl-pyrazole compound anle138b/c reveals that α-synuclein protects melanoma cells from autophagic cell death
Authors: Turriani E, Lázaro DF, Ryazanov S, Leonov A, Giese A, Schön M, Schön MP, Griesinger C, Outeiro TF, Arndt-Jovin DJ, Becker D
Journal: Proc Natl Acad Sci U S A. 2017 Jun 5. pii: 201700200. doi: 10.1073/pnas.1700200114
PMID: 28584093

In their study, the German researchers looked at levels of alpha synuclein in melanoma cells. They took the melanoma cells that produced the most alpha synuclein and treated those cells with a chemical that inhibits the toxic form of alpha synuclein (which results from the accumulation of the protein).

What they observed next was fascinating: the cell morphology (or physically) changed, leading to massive melanoma cell death. The investigators found that this cell death was caused by instability of mitochondria and a major dysfunction in the autophagy process.

Mitochondria, you may recall, are the power house of each cell. They keep the lights on. Without them, the lights go out and the cell dies.

Mitochondria

Mitochondria and their location in the cell. Source: NCBI

Autophagy is the garbage disposal/recycling process within each cell, which is an absolutely essential function. Without autophagy, old proteins and mitochondria will pile up making the cell sick and eventually it dies. Through the process of autophagy, the cell can break down the old protein, clearing the way for fresh new proteins to do their job.

Print

The process of autophagy. Source: Wormbook

Waste material inside a cell is collected in membranes that form sacs (called vesicles). These vesicles then bind to another sac (called a lysosome) which contains enzymes that will breakdown and degrade the waste material. The degraded waste material can then be recycled or disposed of by spitting it out of the cell.

What the German research have found is that the high levels of alpha synuclein keep the mitochondria stable and the autophagy process working at a level that helps to keeps the cancer cell alive.

Next, they replicated this cell culture research in mice with melanoma tumors. When the mice were treated with the chemical that inhibits the toxic form of alpha synuclein, the cancer cancer became malformed and the autophagy process was blocked.

The researchers concluded that “alpha synuclein, which in PD exerts severe toxic functions, promotes and thereby is highly beneficial to the survival of melanoma in its advanced stages”.

So what does all of this mean for Parkinson’s disease?

Well, this is where the story gets really interesting.

You may be pleased to know that the chemical (called Anle138b) which was used to inhibit the toxic form of alpha synuclein in the melanoma cells, also works in models of Parkinson’s disease:

Wagner

Title: Anle138b: a novel oligomer modulator for disease-modifying therapy of neurodegenerative diseases such as prion and Parkinson’s disease.
Authors: Wagner J, Ryazanov S, Leonov A, Levin J, Shi S, Schmidt F, Prix C, Pan-Montojo F, Bertsch U, Mitteregger-Kretzschmar G, Geissen M, Eiden M, Leidel F, Hirschberger T, Deeg AA, Krauth JJ, Zinth W, Tavan P, Pilger J, Zweckstetter M, Frank T, Bähr M, Weishaupt JH, Uhr M, Urlaub H, Teichmann U, Samwer M, Bötzel K, Groschup M, Kretzschmar H, Griesinger C, Giese A.
Journal: Acta Neuropathol. 2013 Jun;125(6):795-813
PMID: 23604588              (This article is OPEN ACCESS if you would like to read it)

In this first study the researchers discovered Anle138b by conducted a large screening study to identify for molecules that could inhibit the toxic form of alpha synuclein.

They next tested Anle138b in both cell culture and rodent models of Parkinson’s disease and found it to be neuroprotective and very good at inhibiting the toxic form of alpha synuclein. And the treatment looks to be very effective. In the image below you can see dark staining of toxic alpha synuclein in the left panel from the brain of an untreated mouse, but very little staining in the right panel from an Anle138b treated mouse.

NL_2014_01_modag

 

Toxic form of alpha synuclein (dark staining). Source: Max-Planck

Importantly, Anle138b does not interfere with normal behaviour of alpha synuclein in the mice (such as production of the protein, correct functioning, and eventual degradation/disposal of the protein), but it does act as an inhibitor of alpha synuclein clustering or aggregation (the toxic form of the protein). In addition, the investigators found no toxic effects of Anle138b in any of their experiments even after long-term high-dose treatment (more than one year).

And in a follow up study, the drug was effective even if it was given after the disease model had started:

Olig2

Title: The oligomer modulator anle138b inhibits disease progression in a Parkinson mouse model even with treatment started after disease onset
Authors: Levin J, Schmidt F, Boehm C, Prix C, Bötzel K, Ryazanov S, Leonov A, Griesinger C, Giese A.
Journal: Acta Neuropathol. 2014 May;127(5):779-80.
PMID: 24615514                (This article is OPEN ACCESS if you would like to read it)

During the first study, the researchers had started Anle138b treatment in the mouse model of Parkinson’s disease at a very young age. In this study, however, the investigators began treatment only as the symptoms were starting to show, and Anle138b was found to significantly improve the overall survival of the mice.

One particularly interesting aspect of Anle138b function in the brain is that it does not appear to change the level of the autophagy suggesting that the biological effects of treatment with Anle138b is cell-type–specific (Click here to read more about this). In cancer cells, it is having a different effect to that in brain cells. These differences in effect may also relate to disease conditions though, as Anle138b was not neuroprotective in a mouse model of Multiple System Atrophy (MSA; Click here to read more about this).

Is Anle138b being tested in the clinic?

Not yet.

Ludwig-Maximilians-Universität München and the Max Planck Institute for Biophysical Chemistry (Göttingen) have spun off a company called MODAG GmbH that is looking to advance Anle138b to the clinic (Click here for the press release). The Michael J Fox Foundation are helping to fund more preclinical development of this treatment (Click here to read more about this).

We will be watching their progress with interest.

What does it all mean?

Summing up: There are many mysteries surrounding Parkinson’s disease, but some researchers from Germany may have just solved one of them and at the same time developed a potentially useful new treatment.

They have discovered that the Parkinson’s associated protein, alpha synuclein, which is produced in large amounts in the skin cancer melanoma, is actually playing an important role in keeping those cancer cells alive. By finding a molecule that can block the build up of alpha synuclein, they have not only found a treatment for melanoma, but also potentially one for Parkinson’s disease.

And given that both diseases are closely associated, this could be seen as a great step forward. Two birds with one stone as the saying goes.


The banner for today’s post was sourced from Wikipedia

Flu jabs and Parkinson’s disease

o-FLU-JAB-facebook

Our apologies to anyone who is squeamish about needles, but this is generally how most people get their seasonal flu vaccination.

Why are we talking about flu vaccines?

Because new research, published last week, suggests everyone should be going out and getting them in the hope of reducing our risk of Parkinson’s disease.

In today’s post we will review the research, exactly what a flu vaccine is, and how it relates to Parkinson’s disease.


influenza-virus-electron-micrograph1

Electron micro photograph of Influenza viruses. Source: Neuro-hemin

Long time readers of the SoPD blog will know that I have a particular fascination with theories regarding a viral or microbial role in the development of Parkinson’s disease (the ‘idiopathic’ – or arising spontaneously – variety at least).

Why?

Numerous reasons. For example:

  • The targeted nature of the condition (why are only selective groups of cells are lost in the brain during the early stages of the condition?)
  • The unexplained protein aggregation (eg. Lewy bodies; could they be a cellular defensive mechanism against viruses/microbes – Click here to read more on this idea)
  • The asymmetry of the onset (why do tremors start on only one side of the body in most cases?)

And we have previously discussed research here on the website regarding possible associations between Parkinson’s disease and and various types of viruses (including Hepatitis C, Herpes Simplex, and Influenza).

Today we re-visit influenza as new research has been published on this topic.

What is influenza?

Influenza is a single-stranded, RNA virus of the orthomyxovirus family of viruses.

3D_Influenza_transparent_key_pieslice_lrg

A schematic of the influenza virus. Source: CDC

It is the virus that causes ‘the flu’ – (runny nose, sore throat, coughing, and fatigue) – with the symptom arising two days after exposure and lasting for about a week. In humans, there are three types of influenza viruses, called Type A, Type B, and Type C. Type A are the most virulent in humans. The influenza virus behind both of the outbreaks in the 1918 pandemic was a Type A.

influenzaha-na

Schematic of Influenza virus. Source: Bcm

As the image above indicates, the influenza virus has a rounded shape, with “HA” (hemagglutinin) and “NA” (neuraminidases) proteins on the outer surface of the virus. The HA protein allows the virus to stick to the outer membrane of a cell. The virus can then infect the host cell and start the process of reproduction – making more copies of itself. The NA protein is required for the virus to exit the host cell and go on to infect other cells. Different influenza viruses have different combinations of hemagglutinin and neuraminidase proteins, hence the numbering. For example, the Type A virus that caused the outbreaks in the 1918 pandemic was called H1N1.

Inside the influenza virus, there are there are eight pieces (segments) of RNA, hence the fact that influenza is an RNA virus. Some viruses have DNA while others have RNA. The 8 segments of RNA provide the information that is required for making new copies of the virus. Each of these segments provides the instructions for making one or more proteins of the virus (eg. segment 4 contains the instructions to make the HA protein).

martinez-influenza-virus

The 8 segments of RNA in influenza. Source: URMC

The Influenza virus is one of the most changeable viruses we are aware of, which makes it such a tricky beast to deal with. Influenza uses two techniques to change over time. They are called shift and drift.

Shifting is an sudden change in the virus, which produces a completely new combination of the HA and NA proteins. Virus shift can take place when a person or animal is infected with two different subtypes of influenza. When new viral particles are generated inside the cell, there is a mix of both subtypes of virus which gives rise to an all new type of virus.

flu-reassortment-320-240-20131210133600

An example of viral shift. Source: Bcm

Drifting is the process of random genetic mutation. Gradual, continuous, spontaneous changes that occur when the virus makes small “mistakes” during the replication of its RNA. These mistakes can results in a slight difference in the HA or NA proteins, and although those changes are small, they can be significant enough that the human immune system will no longer recognise and attack the virus. This is why you can repeatedly get the flu and why flu vaccines must be administered each year to combat new forms of circulating influenza virus.

What is a flu jab exactly?

Seasonal flu vaccination is a treatment that is given each year to minimise the risk of being infected by an influenza virus.

The ‘seasonal’ part of the label refers to the fact that the flu vaccine changes each year. Most flu vaccines target three strains of the viruses (and are thus called ‘Trivalent flu vaccines’) which are selected each year based on data collected by various health organisations around the world.

The three chosen viruses for a particular year are traditionally injected into and grown in hens’ eggs, then harvested and purified before the viral particles are chemically deactivated. The three dead viruses are then pooled together and packaged as a vaccine. As you can see in the image below, the process of vaccine production is laborious and takes a full year:

35619a7

The process of vaccine production. Source: Linkedin

By injecting people with the dead viruses from three different strains of the influenza virus, however, the immune system has the chance to build up a defence against those viruses without the risk of the individual becoming infected (the dead viruses in the vaccine can not infect cells).

Flu vaccines cause the immune system to produce antibodies which are used by the immune system to help defend the body against future attacks from viruses. These antibodies generally take about two weeks to develop in the body after vaccination.

As we have said most injected flu vaccines protect against three types of flu virus. Generally each of the three viruses is taken from the following strains:

  • Influenza A (H1N1) – the strain of flu that caused the swine flu pandemic in 2009.
  • Influenza A (H3N2) – a strain of flu that mainly affects the elderly and people at risk with long term health conditions. In 2016/17 the vaccine contains an A/Hong Kong/4801/2014 H3N2-like virus.
  • Influenza B – a strain of flu that particularly affects children. In 2016/17 the vaccine contains B/Brisbane/60/2008-like virus.

How effective are the vaccines?

Well, it really depends on which strains of influenza are going to affect the most people each year, and this can vary greatly. Overall, however, research from the Centers for Disease Control and Prevention (or CDC) suggests that the seasonal flu vaccine reduces the chance of getting sick by approximately 50% (Source). Not bad when you think about it.

Ok, so are there actually any connections between influenza and Parkinson’s disease?

This question is up for debate.

There are certainly some tentative associations between influenza and Parkinson’s disease. Early on, those connections were coincidental, but more recently research is suggesting that there could be a closer relationship.

Coincidental?

Between January 1918 and December 1920 there were two outbreaks of an influenza virus during an event that became known as the 1918 flu pandemic. Approximately 500 million people across the globe were infected by the H1N1 influenza virus, and this resulted in 50 to 100 million deaths (basically 3-5% of the world’s population). Given that is occurred during World War 1, censors limited the media coverage of the pandemic in many countries in order to maintain morale. The Spanish media were not censored, however, and this is why the 1918 pandemic is often referred to as the ‘Spanish flu’.

photo_66943_landscape_650x433

1918 Spanish flu. Source: Chronicle

At the same time that H1N1 was causing havoc, a Romanian born neurologist named Constantin von Economo reported a number of unusual symptoms which were referred to as encephalitis lethargica (EL). This disease left victims in a statue-like condition, speechless and motionless.

Economo

Constantin von Economo. Source: Wikipedia

By 1926, EL had spread around the world, with nearly five million people being affected. Many of those who survived never returned to their pre-existing state of health. They were left frozen in an immobile state.

vonecomo-parkinson

An individual with encephalitis lethargica. Source: Baillement

Historically, it was believed that EL was caused by the influenza virus from the 1918 Spanish influenza pandemic. This was largely due to a temporal association (things happening at approximately the same time) and the finding of influenza antigens in some of the suffers of EL (Click here to read more about this).

And then there were also the observations of Dr Oliver Sacks:

Oliver-Sacks-1933-2015-1

Amazing guy! Dr Oliver Sacks. Source: Pensologosou

During the late 1960s, while employed as a neurologist at Beth Abraham Hospital’s chronic-care facility in New York, Dr Sacks began working with a group of survivors of EL, who had been left immobile by the condition. He treated these individuals with L-dopa (the standard treatment for Parkinson’s disease now, but it was still experimental at the time) and he observed them become miraculously reanimated. The sufferers went from being completely motionless to suddenly active and mobile. Unfortunately the beneficial effects were very short lived.

You may be familiar with Dr Sack’s book about his experience of treating these patients. It is called ‘Awakenings’ and it was turned into a film starring actors Robin Williams and Robert De Niro.

robin_williams_con_robert_de_niro_en_1990

Robin Williams and Robert De Niro in Awakenings. Source: Pinterest

More recent, postmortem analysis of the brains of EL patients found an absence of influenza RNA – click here for more on this), which has led many researchers to simply reject the association between influenza and EL. The evidence supporting this rejection, however, has also been questioned (click here to read more on this), leaving the question of an association between influenza and EL still open for debate.

I think it’s fair to say that we genuinely do not know what caused EL. Whether it was influenza or not is still be undecided.

Ok, so that was the coincidental evidence. Has there been a more direct connection between influenza and Parkinson’s disease?

This is Dr Richard J Smeyne:

Richard_Smeyne

Source: Researchgate

Nice guy.

He is a research faculty member in the Department of Developmental Neurobiology at St. Jude Children’s Research Hospital (Memphis, Tennessee).

He has had a strong interest in what role viruses like influenza could be playing in the development of Parkinson’s disease, and his research group has published several interesting research reports on this topic, including:

PNAS

Title: Highly pathogenic H5N1 influenza virus can enter the central nervous system and induce neuroinflammation and neurodegeneration.
Author: Jang H, Boltz D, Sturm-Ramirez K, Shepherd KR, Jiao Y, Webster R, Smeyne RJ.
Journal: Proc Natl Acad Sci U S A. 2009 Aug 18;106(33):14063-8.
PMID: 19667183                 (This article is OPEN ACCESS if you would like to read it)

Dr Smeyne and his colleagues found in this study that when they injected the highly infectious A/Vietnam/1203/04 (H5N1) influenza virus into mice, the virus progressed from the periphery (outside the brain) into the brain itself, where it induced Parkinson’s disease-like symptoms.

The virus also caused a significant increase in the accumulation of the Parkinson’s disease-associated protein Alpha Synuclein. In addition, they witnessed the loss of dopamine neurons in the midbrain of the mice at 60 days after the infection – that cell loss resembling what is observed in the brains of people with Parkinson’s disease.

Naturally this got the researchers rather excited!

In a follow up study on H5N1, however, these same researchers found that the Parkinson’s disease-like symptoms that they observed were actually only temporary:

JNS

Title: Inflammatory effects of highly pathogenic H5N1 influenza virus infection in the CNS of mice.
Authors: Jang H, Boltz D, McClaren J, Pani AK, Smeyne M, Korff A, Webster R, Smeyne RJ.
Journal: Journal for Neuroscience, 2012 Feb 1;32(5):1545-59.
PMID: 22302798                   (This article is OPEN ACCESS if you would like to read it)

Dr Smeyne and colleagues repeated the 2009 study and had a closer look at what was happening to the dopamine neurons that were disappearing at 60 days post infection with the virus. When they looked at mice at 90 days post infection, they found that the number of dopamine neurons had returned to their normal number. This pattern was also observed in a region of the brain called the striatum, where the dopamine neurons release their dopamine. The levels of dopamine dropped soon after infection, but rose back to normal by 90 days post infection.

How does that work?

The results suggest that rather than developing new dopamine neurons in some kind of miraculous regenerative process, the dopamine neurons that were infected by the virus simply stopped producing dopamine while they dealt with the viral infection. Once the crisis was over, the dopamine neurons went back to life as normal. And because the researcher use chemicals in the production of dopamine to identify the dopamine neurons, they mistakenly thought that the cells had died when they couldn’t see those chemicals.

One interesting observation from the study was that H5N1 infection in mice induced a long-lasting inflammatory response in brain. The resident helper cells, called microglia, became activated by the infection, but remained active long after the dopamine neurons returned to normal service. The investigators speculated as to whether this activation may be a contributing factor in the development of neurodegenerative disorders.

And this is an interesting idea.

In a follow up study, they investigated this further by looking another influenza viruse that doesn’t actually infect cells in the brain:

PLOS

Title: Induction of microglia activation after infection with the non-neurotropic A/CA/04/2009 H1N1 influenza virus.
Author: Sadasivan S, Zanin M, O’Brien K, Schultz-Cherry S, Smeyne RJ.
Journal: PLoS One. 2015 Apr 10;10(4):e0124047.
PMID: 25861024                (This article is OPEN ACCESS if you would like to read it)

In this study, a different type of influenza (H1N1) was tested, and while it did not infect the brain, it did cause the microglia cells to flare up and become activated. And again, this activation was sustained for a long period after the infection (at least 90 days).

This is a really interesting finding and relates to the idea of a “double hit” theory of Parkinson’s disease, in which the virus doesn’t necessarily cause Parkinson’s disease but may play a supplemental or distractionary role, grabbing the attention of the immune system while some other toxic agent is also attacking the body. Or perhaps simply weakening the immune system by forcing it to fight on multiple fronts. Alone the two would not cause as much damage, but in combination they could deal a terrible blow.

So what was the flu vaccine research published last week?

Again, from Dr Smeyne’s research group, this report looked whether the combination of an influenza virus infection plus a toxic agent gave a worse outcome than just the toxic agent by itself. An interesting idea for a study, but then the investigators threw in another component: what effect would a influenza vaccine have in such an experiment. And the results are interesting:

Flu

Title: Synergistic effects of influenza and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) can be eliminated by the use of influenza therapeutics: experimental evidence for the multi-hit hypothesis
Authors: Sadasivan S, Sharp B, Schultz-Cherry S, & Smeyne RJ
Journal: npj Parkinson’s Disease 3, 18
PMID: N/A                    (This article is OPEN ACCESS if you would like to read it)

What the researchers found was that H1N1-infected mice that were treated with a neurotoxin (called MPTP – a toxin that specifically kills dopamine neurons) exhibit a 20% greater loss of dopamine neurons than mice that were treated with MPTP alone.

And this increase in dopamine neuron loss was completely eliminated by giving the mice the influenza vaccination. The researchers concluded that the results demonstrate that multiple insults (such as a viral infection and a toxin) can enhance the impact, and may even be significant in allowing an individual to cross a particular threshold for developing a disease.

It’s an intriguing idea.

Have epidemiologists (population data researchers) ever investigated a connection between Parkinson’s disease and influenza?

Good question.

And yes they have:

flu1
Title: Parkinson’s disease or Parkinson symptoms following seasonal influenza.
Authors: Toovey S, Jick SS, Meier CR.
Journal: Influenza Other Respir Viruses. 2011 Sep;5(5):328-33.
PMID: 21668692            (This article is OPEN ACCESS if you would like to read it)

In this first study, the researcher used the UK‐based General Practice Research Database to perform a case–control analysis (that means they compare an affected population with an unaffected ‘control’ population. They identified individual cases who had developed an ‘incident diagnosis’ of Parkinson’s disease or Parkinson’s like symptoms between 1994 and March 2007. For each of those case files identified, they matched them with at least four age matched control case files for comparative sake.

Their analysis found that the risk of developing Parkinson’s disease was not associated with previous influenza infections. BUT, they did find that Influenza was associated with Parkinson’s‐like symptoms such as tremor, particularly in the month after an infection. One can’t help but wonder if the dopamine neurons stopped producing dopamine during that period while they dealt with the viral infection.

But of course, I’m only speculating here… and it’s not like there was a second study suggesting that there is actually an association between Parkinson’s disease and influenza.

A year after that first study, a second study was published:

occupation
Journal: Association of Parkinson’s disease with infections and occupational exposure to possible vectors.
Authors: Harris MA, Tsui JK, Marion SA, Shen H, Teschke K.
Journal: Movement Disorder. 2012 Aug;27(9):1111-7.
PMID: 22753266

This second study reported that there is actually an association between Parkinson’s disease and influenza.

This investigation was also a case-control study, but it was based in British Columbia, Canada. The researchers recruited 403 individuals detected by their use of antiparkinsonian medications and matched them with 405 control subjects selected from the universal health insurance plan. Severe influenza was associated with Parkinson’s disease at an odds ratio of 2.01 (1 being no difference) and the range of the odds was 1.16-3.48. That’s pretty significant.

Interestingly, the effect is reduced when the reports of infection were restricted to those occurring within 10 years before diagnosis. This observation would suggest that early life infections may have more impact than previously thought.

Curiously, the researchers also found that exposure to certain animals (cats odds ration of 2.06; range 1.09-3.92) and cattle (2.23; range 1.22-4.09) was also associated with developing Parkinson’s disease.

Time to get rid of the pet cow.

1016238_tcm9-156853

Source: RSPB

Do any other neurodegenerative condition have associations with influenza?

In the limited literature search that we conducted, we only found reports dealing with influenza and Alzheimer’s disease.

Large studies suggest that Alzheimer’s is not associated with influenza (click here to read more on this). Interestingly, the Alzheimer’s associated protein beta amyloid has been shown to inhibit influenza A viruses (Click here to read that report), which may partly explain the lack of any association.

Influenza does have a mild association, however, with depression (Click here to see that report).

So what does it all mean?

A viral theory for Parkinson’s disease has existed since the great epidemic of 1918. Recent evidence points towards several viruses potentially having some involvement in the development of this neurodegenerative condition. And recent evidence suggests that influenza in particular could be particularly influential.

In 1938, Jonas Salk and Thomas Francis developed the first vaccine against flu viruses. It could be interesting for epidemiologists to go back and see if regular flu vaccination usage (if such data exists) reduces the risk of developing Parkinson’s disease.

But until such data is published, however, perhaps it would be wise to go and get a flu vaccine shot.


The banner for today’s post was sourced from the HuntingtonPost

New stem cell transplantation trial for Parkinson’s proposed in China

7661_Screen-Shot-2013-11-08-at-11.37.38-AM

We have been contacted by some readers asking about a new stem cell transplantation clinical trial for Parkinson’s disease about to start in China (see the Nature journal editorial regarding this new trial by clicking here).

While this is an exciting development, there have been some concerns raised in the research community regarding this trial.

In today’s post, we will discuss what is planned and what it will mean for stem cell transplantation research.


Deep-Brain-Stimulation-60pghfsukanm4j4bljb8mbq9hyafm3pj0e6t4iuyndm

Brain surgery. Source Bionews-tx

Parkinson’s disease is a progressive neurodegenerative condition.

This means that cells in the brain are slowly being lost over time. What makes the condition particularly interesting is that certain types of brain cells are more affected than others. The classic example of this is the dopamine neurons in an area of the brain called the substantia nigra, which resides in the midbrain.

d1ea3d21c36935b85043b3b53f2edb1f87ab7fa6

The number of dark pigmented dopamine cells in the substantia nigra are reduced in the Parkinson’s disease brain (right). Source: Adapted from Memorangapp

Approximately 50% of the dopamine neurons in the midbrain have been lost by the time a person is diagnosed with Parkinson’s disease (note the lack of dark colouration in the substantia nigra of the Parkinsonian brain in the image above), and as the condition progresses the motor features – associated with the loss of dopamine neurons – gradually get worse. This is why dopamine replacement treatments (like L-dopa) are used for controlling the motor symptoms of Parkinson’s disease.

A lot of research effort is being spent on finding disease slowing/halting treatments, but these will leave many people who have already been diagnosed with Parkinson’s disease still dealing with the condition. What those individuals will require is a therapy that will be able to replace the lost cells (particularly the dopamine neurons). And researchers are also spending a great deal of time and effort on findings ways to do this. One of the most viable approaches at present is cell transplantation therapy. This approach involves actually injecting cells back into the brain to adopt the functions of the lost cells.

How does cell transplantation work?

We have discussed the history of cell transplantation in a previous post (Click here to read that post), and today we are simply going to focus on the ways this experimental treatment is being taken forward in the clinic.

Many different types of cells have been tested in cell transplantation experiments for Parkinson’s disease (Click here for a review of this topic), but to date the cells that have given the best results have been those dissected from the developing midbrain of aborted embryos.

This now old fashioned approach to cell transplantation involved dissecting out the region of the developing dopamine neurons from a donor embryo, breaking up the tissue into small pieces that could be passed through a tiny syringe, and then injecting those cells into the brain of a person with Parkinson’s disease.

gr3

The old cell transplantation process for Parkinson’s disease. Source: The Lancet

Critically, the people receiving this sort of transplant would require ‘immunosuppression treatment’ for long periods of time after the surgery. This additional treatment involves taking drugs that suppress the immune system’s ability to defend the body from foreign agents. This step is necessary, however, in order to stop the body’s immune system from attacking the transplanted cells (which would not be considered ‘self’ by the immune system), allowing those cells to have time to mature, integrate into the brain and produce dopamine.

The transplanted cells are injected into an area of the brain called the putamen. This is one of the main regions of the brain where the dopamine neurons of the substantia nigra release their dopamine. The image below demonstrates the loss of dopamine (the dark staining) over time as a result of Parkinson’s disease (PD):

m_awt192f1p

The loss of dopamine in the putamen as Parkinson’s disease progresses. Source: Brain

In cell transplant procedures for Parkinson’s disease, multiple injections are usually made in the putamen, allowing for deposits in different areas of the structure. These multiple sites allow for the transplanted cells to produce dopamine in the entire extent of the putamen. And ideally, the cells should remain localised to the putamen, so that they are not producing dopamine in areas of the brain where it is not desired (possibly leading to side effects).

image2

Targeting transplants into the putamen. Source: Intechopen

Postmortem analysis – of the brains of individuals who have previously received transplants of dopamine neurons and then subsequently died from natural causes – has revealed that the transplanted cells can survive the surgical procedure and integrate into the host brain. In the image below, you can see rich brown areas of the putamen in panel A. These brown areas are the dopamine producing cells (stained in brown). A magnified image of individual dopamine producing neurons can be seen in panel B:

Microsoft Word - Li W-Revision-Final.docx

Transplanted dopamine neurons. Source: Sciencedirect

The transplanted cells take several years to develop into mature neurons after the transplantation surgery, and the benefits of the transplantation technique may not be apparent for some time (2-3 years on average). Once mature, however, it has also been demonstrated (using brain imaging techniques) that these transplanted cells can produce dopamine. As you can see in the images below, there is less dopamine being processed (indicated in red) in the putamen of the Parkinsonian brain on the left than the brain on the right (several years after bi-lateral – both sides of the brain – transplants):

3_2

Brain imaging of dopamine processing before and after transplantation. Source: NIH

Sounds like a great therapy for Parkinson’s disease right?

So why aren’t we doing it???

Two reasons:

1. The tissue used in the old approach for cell transplantation in Parkinson’s disease was dissected from embryonic brains. Obviously there are serious ethical and moral problems with using this kind of tissue. There is also a difficult problem of supply: tissue from at least 3 embryos is required for transplanting each side of the brain (6 embryos in total). Given these issues, researchers have focused their attention on a less controversial and more abundant supply of cells: brain cells derived from embryonic stem cells (the new approach to cell transplantation).

1024px-Humanstemcell

Human embryonic stem cells. Source: Wikipedia

2. The second reason why cell transplantation is not more widely available is that in the mid 1990’s, the US National Institutes of Health (NIH) provided funding for the two placebo-controlled, double blind studies to be conducted to test the efficacy of the approach. Unfortunately, both studies failed to demonstrate any beneficial effects on Parkinson’s disease features.

In addition, many (15% – 50%) of transplanted subjects developed what are called ‘graft-induced dyskinesias’. This involves the subjects display uncontrollable/erratic movement (or dyskinesias) as a result of the transplanted cells. Interestingly, patients under 60 years of age did show signs of improvement on when assessed both clinically (using the UPDRS-III) and when assessed using brain imaging techniques (increased F-dopa uptake on PET).

Both of the NIH trials have been criticised by experts in the field for various procedural failings that could have contributed to the failures. But the overall negative results left a dark shadow over the technique for the better part of a decade. Researchers struggled to get funding for their research.

And this is the reason why many researchers are now urging caution with any new attempts at cell transplantation clinical trials in Parkinson’s disease – any further failures will really harm the field, if not kill if off completely.

Are there any clinical trials for cell transplantation in Parkinson’s disease currently being conducted?

Yes, there are currently two:

Firstly there is the Transeuro being conducted in Europe.

Transeuro_Logo_100

The Transeuro trial. Source: Transeuro

The Transeuro trial is an open label study, involving 40 subjects, transplanted in different sites across Europe. They will receive immunosuppression for at least 12 months post surgery, and the end point of the study will be 3 years post surgery, with success being based on brain imaging of dopamine release from the transplanted cells (PET scans). Based on the results of the previous NIH funding double blind clinical studies discussed above, only subject under 65 years of age have been enrolled in the study.

transeuro

The European consortium behind the Transeuro trial. Source: Transeuro

In addition to testing the efficacy of the cell transplantation approach for Parkinson’s disease, another goal of the Transeuro trial is to optimise the surgical procedures with the aim of ultimately shifting over to an embryonic stem cells oriented technique in the near future with the proposed G-Force embryonic stem cell trials planned for 2018 (the Transeuro is testing the old approach to cell transplantation).

The second clinical study of cell transplantation for Parkinson’s disease is being conducted in Melbourne (Australia), by an American company called International Stem Cell Corporation.

logo

This study is taking the new approach to cell transplantation, but the company is using a different type of stem cell to produce dopamine neurons in the Parkinsonian brain.

Specifically, the researchers will be transplanting human parthenogenetic stem cells-derived neural stem cells (hpNSC). These hpNSCs come from an unfertilized egg – that is to say, no sperm cell is involved. The female egg cell is chemically encouraged to start dividing and then it becoming a collection of cells that is called a blastocyst, which ultimately go on to contain embryonic stem cell-like cells.

stem-cell-cultivation-3

The process of attaining embryonic stem cells. Source: Howstuffworks

This process is called ‘Parthenogenesis’, and it’s not actually as crazy as it sounds as it occurs naturally in some plants and animals (Click here to read more about this). Proponents of the parthenogenic approach suggest that this is a more ethical way of generating ES cells as it does not result in the destruction of a viable organism.

Regular readers of this blog will be aware that we are extremely concerned about this particular trial (Click here and here to read previous posts about this). Specifically, we worry that there is limited preclinical data from the company supporting the efficacy of these hpNSC cells being used in the clinical study (for example, researchers from the company report that the hpNSC cells they inject spread well beyond the region of interest in the company’s own published preclinical research – not an appropriate property for any cells being taken to the clinic). We have also expressed concerns regarding the researchers leading the study making completely inappropriate disclosures about the study while the study is ongoing (Click here to read more about this). Such comments only serve the interests of the company behind the study. And this last concern has been raised again with a quote in the Nature editorial about the Chinese trial:

“Russell Kern, chief scientific officer of the International Stem Cell Corporation in Carlsbad, California, which is providing the cells for and managing the Australian trial, says that in preclinical work, 97% of them became dopamine-releasing cells” (Source)

We are unaware of any preclinical data produced by Dr Kern and International Stem Cell Corporation…or ANY other research lab in the world that has achieved 97% dopamine-releasing cells. We (and others) would be interested in learning more about Dr Kerns amazing claim.

The International Stem Cell Corporation clinical trial is ongoing. For more details about this second ongoing clinical trial, please click here.

So what do we know about the new clinical study?

The clinical trial (Titled: A Phase I/II, Open-Label Study to Assess the Safety and Efficacy of Striatum Transplantation of Human Embryonic Stem Cells-derived Neural Precursor Cells in Patients With Parkinson’s Disease) will take place at the First Affiliated Hospital of Zhengzhou University in Henan province.

The researchers are planning to inject neuronal-precursor cells derived from embryonic stem cell into the brains of individuals with Parkinson’s disease. They have 10 subjects that they have found to be well matched to the cells that they will be injecting, which will help to limit the chance of the cells being rejected by the body.

In testing the safety and efficacy of these cells, the trial will have two primary outcome measures:
  1. Incidence of treatment-emergent adverse events, as assessed by brain imaging and blood examination at 6 months post transplant.
  2. Number of subjects with adverse events (such as the evidence of transplant failure or rejection)

In addition to these, there will also be a series of secondary outcome measures, which will include:

  1. Change in Unified Parkinson’s Disease Rating Scale (UPDRS) score at 12 months post surgery, when compared to baseline scores. Each subject was independently rated by two observers at each study visit and a mean score was calculated for analysis.
  2. Change in DATscan brain imaging at 12 months when compared to a baseline brain scan taken before surgery. DATscan imaging provides an indication of dopamine processing.
  3. Change in Hoehn and Yahr Stage at 12 months, compared to baseline scores. The Hoehn and Yahr scale is a commonly used system for Parkinson’s disease.

The trial will be a single group, non-randomized analysis of the safety and efficacy of the cells. The estimated date of completion is December 2020.

Why are some researchers concerned about the study?

Professor Qi Zhou, a stem-cell specialist at the Chinese Academy of Sciences Institute of Zoology will be leading the study and he has a REALLY impressive track record in the field of stem cell biology. His team undertaking this study have a great deal of experience working with embryonic stem cells, having published some extremely impressive research on this topic. But, (and it’s a big but) they have published a limited amount of research in peer-reviewed journals on cell transplantation in models of Parkinson’s disease. Lorenz Studer is one of the leading scientists in this field, was quoted in an editorial in the journal Nature this week:

“Lorenz Studer, a stem-cell biologist at the Memorial Sloan Kettering Cancer Center in New York City who has spent years characterizing such neurons ahead of his own planned clinical trials, says that “support is not very strong” for the use of precursor cells. “I am somewhat surprised and concerned, as I have not seen any peer-reviewed preclinical data on this approach,” he says.” (Source)

In addition to the lack of published research by the team undertaking the trial, the research community is also worried about the type of cells that are going to be transplanted in this clinical trial. Most of the research groups heading towards clinical trials in this area are all pushing embryonic stem cells towards a semi-differentiated state. That is, they are working on recipes that help the embryonic stem cells grow to the point that they have almost become dopamine neurons. Prof Zhou and his colleagues, however, are planning to transplant a much less differentiated type of cell called a neural-precursor cell in their transplants.

Pan

Neuronal-precursor cells. Source: Wired

Neuronal-precursors are very early stage brain cells. They are most likely being used in the study because they will survive the transplantation procedure better than a more mature neurons which would be more sensitive to the process – thus hopefully increasing the yield of surviving cells. But we are not sure how the investigators are planning to orient the cells towards becoming dopamine neurons at such an early stage of their development. Neuronal-precursors could basically become any kind of brain cell. How are the researchers committing them to become dopamine neurons?

Are these concerns justified?

We feel that there are justified reasons for concern.

While Prof Zhou and his colleagues have a great deal of experience with embryonic stem cells and have published very impressive research on that topic, the preclinical data for this trial is limited. In 2015, the research group published this report:

zhou
Title: Lmx1a enhances the effect of iNSCs in a PD model
Authors: Wu J, Sheng C, Liu Z, Jia W, Wang B, Li M, Fu L, Ren Z, An J, Sang L, Song G, Wu Y, Xu Y, Wang S, Chen Z, Zhou Q, Zhang YA.
Journal: Stem Cell Res. 2015 Jan;14(1):1-9.
PMID: 25460246              (This article is OPEN ACCESS if you would like to read it)

In this study, the researchers engineered embryonic stem cells to over-produce a protein called LMX1A to help produce dopamine neurons. LMX1A is required for the development of dopamine neurons (Click here to read more about this). The investigators then grew these cells in cell culture and compared their ability to develop into dopamine neurons against embryonic stem cells with normal levels of LMX1A. After 14 days in cell culture, 16% of the LMX1A cells were dopamine neurons, compared to only 5% of the control cells.

When the investigators transplanted these cells into a mouse model of Parkinson’s disease, they found that the behavioural recovery in the mice did not differ from the control injected mice, and when they looked at the brains of the mice 11 weeks after transplantation “very few engrafted cells had survived”.

In addition to this previously published work, the Chinese team do have unpublished research on 15 monkeys that have undergone the neuronal-precursor cell transplantation procedure having had Parkinson’s disease induced using a neurotoxin. The researchers have admitted that they initially did not see any improvements in movement (which is expected given the slow maturation of the cells). At the end of the first year, however, they examined the brains of some of the monkeys and they found that the transplanted stem cells had turned into dopamine-releasing cells (exactly what percentage of the cells were dopamine neurons is yet to be announced). The monkey study has been running for several years now and they have seen a 50% improvement in the motor ability of the remaining monkeys, supported by brain imaging data. The publication of this research is in preparation, but it probably won’t be available until after the trial has started.

So yes, there is a limited amount of preclinical research supporting the clinical trial.

As for concerns regarding the type of cells that are going to be transplanted:

Embryonic stem cells have robust tumour forming potential. If you inject them into the brain of mice, there is the potential for them to develop into dopamine neurons, but also tumours:

Ole
Title: Embryonic stem cells develop into functional dopaminergic neurons after transplantation in a Parkinson rat model
Authors: Bjorklund LM, Sánchez-Pernaute R, Chung S, Andersson T, Chen IY, McNaught KS, Brownell AL, Jenkins BG, Wahlestedt C, Kim KS, Isacson O.
Journal: Proc Natl Acad Sci U S A. 2002 Feb 19;99(4):2344-9.
PMID: 11782534               (This article is OPEN ACCESS if you want to read it)

In this study, the researchers found that of the twenty-five rats that received embryonic stem cell injections into their brains to correct the modelled Parkinson’s disease, five rats died before completed behavioural assessment and the investigators found teratoma-like tumours in their brains – less than 16 weeks after the cells had been transplanted.

eb7315426f2171c7cb96dc4d980686_big_gallery

A teratoma (white spot) inside a human brain. Source: Radiopaedia

Given this risk of tumour formation, research groups in the cell transplantation field have been trying to push the embryonic stem cells as far away from their original pluripotent state and as close to a dopamine fate as possible without producing mature dopamine neurons which will not survive the transplantation procedure very well.

Prof Zhou’s less mature neuronal-precursor cells are closer to embryonic stem cells than dopamine neurons on this spectrum than the kinds of cells other research groups are testing in cell transplantation experiments. As a result, we are curious to know what precautions the investigators are taking to limit the possibility of an undifferentiated, still pluripotent embryonic stem cell from slipping into this study (the consequences could be disastrous). And given their results from the LMX1A study described above, we are wondering how they are planning to push the cells towards a dopamine fate. If they do not have answers to this issues, they should not be rushing to the clinic with these cells.

So yes, there are reasons for concern regarding the cells that the researchers plan to use in this clinical trial.

And, as with the International Stem Cell Corporation stem cell trial in Australia, we also worry that the follow up-period (or endpoint in the study) of 12 months is not long enough to determine the efficacy of these cells in improving Parkinson’s rating scores and brain imaging results. All of the previous clinical research in this field indicates that the transplanted cells require years of maturation before their dopamine production has an observable impact on the participant. Using 12 months as an end point for this study is tempting a negative result when the long term outcome could be positive.

As we mentioned above, any negative outcomes for these studies could have dire consequences for the field as a whole.

So what does it all mean?

Embryonic stem cells hold huge potential in the field of regenerative medicine. Their ability to become any cell type in the body means that if we can learn how to control them correctly, these cells could represent a fantastic new tool for future cell replacement therapies in conditions like Parkinson’s disease.

Strong demand for such therapies from groups like the Parkinsonian community, has resulted in research groups rushing to the clinic with different approaches using these cells. Concerns as to whether such approaches are ready for the clinic are warranted, if only because mistakes by individual research groups/consortiums in the past have caused delays for everyone in the field.

While China is very keen (and should be encouraged) to take bold steps in its ambition to be a world leader in this field, open and transparent access to extensive preclinical research would help assuage concerns within the research community that prudent care is being taken heading forward.

We’ll keep you aware of developments in this clinical trial.


EDITORIAL NOTE No.1 – It is important for all readers of this post to appreciate that cell transplantation for Parkinson’s disease is still experimental. Anyone declaring otherwise (or selling a procedure based on this approach) should not be trusted. While we appreciate the desperate desire of the Parkinson’s community to treat the disease ‘by any means possible’, bad or poor outcomes at the clinical trial stage for this technology could have serious consequences for the individuals receiving the procedure and negative ramifications for all future research in the stem cell transplantation area. 

EDITORIAL NOTE No.2 – the author of this blog is associated with research groups conducting the current Transeuro transplantation trials and the proposed G-Force embryonic stem cell trials planned for 2018. He has endeavoured to present an unbiased coverage of the news surrounding the current clinical trials, though he shares the concerns of the Parkinson’s scientific community that the research supporting the current Australian trial is lacking in its thoroughness and will potentially jeopardise future work in this area. He is also concerned by the lack of peer-reviewed published research on cell transplantation in models of Parkinson’s disease for the proposed clinical studies in China. 


The banner for today’s post was sourced from Ozy

Oleuropein – “surely the richest gift of heaven?”

thomas-jefferson

The title of this post is a play on a Thomas Jefferson quote (“the olive tree is surely the richest gift of heaven“). Jefferson, the third President of the United States (1801 to 1809), was apparently quite the lover of food. During the Revolutionary War, while he was a U.S. envoy to France, Jefferson travelled the country. In Aix-en-Provence, he developed an admiration for olive trees, calling them “the most interesting plant in existence”.

Being huge food lovers ourselves, we here at the SoPD wholeheartedly agree with Jefferson. But we also think that olives are interesting for another reason:

They contain a chemical called Oleuropein.

In today’s post we’ll explore what is known about this chemical and discuss what it could mean for Parkinson’s disease.


olivve-pits

Olives. Source: Gardeningknowhow

The olive, also known by the botanical name ‘Olea europaea,’ is an evergreen tree that is native to the Mediterranean, Asia and Africa, but now found around the world. It has a rich history of economic and symbolic importance within western civilisation. And the fruit of the tree also tastes good, either by themselves or in a salad or pasta dish.

Traditional diets of people living around the Mediterranean sea are very rich in extra-virgin olive oil. Olives are an excellent source of ‘good’ fatty acids (monounsaturated and di-unsaturated), antioxidants and vitamins. Indeed, research has shown that the traditional Mediterranean diet reduces the risk of heart disease (Click here to read more on this).

preview

Olive oil. Source: Bonzonosvilla

There are also chemicals within the olive fruit that may have very positive benefits for Parkinson’s disease.

But before you rush out and gorge yourself on olives, we have one small piece of advice:

The chemical is called Oleuropein, and it is usually removed from olives due to its bitterness.

What is Oleuropein?

Oleuropein is a ‘phenylethanoid’ – a type of phenolic compound that is found in the leaf and the fruit of the olive. Phenolic compounds are produced by plants as a protective measure against different kinds of stress.

Oleuropein

Oleuropein. Source: Wikipedia

The main phenolic compounds found in olives are hydroxytyrosol and oleuropein – both of which give extra-virgin olive oil its bitter taste and both have demonstrated neuroprotective effects.

More research has been done on oleuropein so we will focus on it here (for more on hydroxytyrosol – please click here).

Oleuropein has been found to have many interesting properties, such as:

ijms-15-18508-ag

The many properties of oleuropein. Source: Mdpi

What neuroprotective research has been done on Oleuropein?

Thus far, most of the research addressing this question has been conducted on models of Alzheimer’s disease. The first study

PLos1

Title: Oleuropein aglycone protects transgenic C. elegans strains expressing Aβ42 by reducing plaque load and motor deficit.
Authors: Diomede L, Rigacci S, Romeo M, Stefani M, Salmona M.
Journal: PLoS One. 2013;8(3):e58893.
PMID: 23520540                 (This article is OPEN ACCESS if you would like to read it)

The Italian researchers who conducted this study treated a microscopic worm model of Alzheimer’s disease with oleuropein aglycone. We should not that oleuropein aglycone is a hydrolysis product of oleuropein (a hydrolysis product is a chemical compound that is broken apart by the addition of water). The microscopic worm used in the study are called Caenorhabditis elegans:

c_elegans

Caenorhabditis elegans – cute huh? Source: Nematode

Caenorhabditis elegans (or simply C. Elegans) are tiny creatures that are widely used in biology because they can be easily genetically manipulated and their nervous system is very simple and well mapped out (they have just 302 neurons and 56 glial cells!). The particular strain of C. elegans used in this first study produced enormous amounts of a protein called Aβ42.

Amyloid beta (or Aβ) is the bad boy/trouble maker of Alzheimer’s disease; considered to be critically involved in the condition. A fragment of this protein (called Aβ42) begins clustering in the brains of people with Alzheimer’s disease. This clustering of Aβ42 goes on to form the plaques that are so characteristic of the Alzheimer’s affected brain.

The Italian researchers conducting this study had previously shown that oleuropein can inhibit the ability of Aβ42 to aggregate in cells growing in culture dishes (Click here to read more about that study), and they wanted to see if oleuropein had the same properties in actual live animals. So they chose the C. Elegans that had been genetically engineered to produce a lot of Aβ42 to test this idea.

In the C. Elegans that produce a lot of Aβ42 gradually become paralysed and their lives are shortened. By treating these worms with oleuropein, however, the Italian researchers found that there was less aggregation of Aβ42 (though the levels of the protein stayed the same), resulting in less plaque formation, and improved mobility (>50% reduction in paralysis) and survival compared to untreated Aβ42 producing C. Elegans.

Encouraged by this result, the researchers next moved on to studies in mice:

Plos2

Title: The polyphenol oleuropein aglycone protects TgCRND8 mice against Aß plaque pathology.
Authors: Grossi C, Rigacci S, Ambrosini S, Ed Dami T, Luccarini I, Traini C, Failli P, Berti A, Casamenti F, Stefani M.
Journal: PLoS One. 2013 Aug 8;8(8):e71702.
PMID: 23951225                   (This article is OPEN ACCESS if you would like to read it)

For this study, the Italian researchers used the genetically engineered TgCRND8 mice. These mice have a mutant form of amyloid precursor protein (which, similar to Aβ42, is associated with Alzheimer’s disease). In the brains of these mice, amyloid clustering begins at 3 months of age, and dense plaques are evident from 5 months of age. The mice also exhibit a clear learning impairment from 3 months of age.

By treating these mice with oleuropein aglycone, the researchers observed a remarkable reduction in plaques in the brain, and those that were present appeared less compact and “fluffy” (their very technical description, not ours). In addition, there was a reduction in the activation of astrocytes and microglia (the helper cells in the brain), indicating a healthier environment.

These same researchers have observed the same results in a rat model of Alzheimer’s disease in a report published the next year (Click here to read more about this).

Interestingly, the oleuropein treated TgCRND8 mice also displayed a major increase in autophagy activity. As we discussed in our previous post (Click here to read that post), autophagy is the rubbish disposal/recycling system of each cell, and increasing the activity of this system can help to keep cells health (particularly if there is a lot of a genetically engineered protein present!).

The Italian researchers repeated this study, and published the results this year, with an interesting twist:

JCBP

Title: Oleuropein aglycone and polyphenols from olive mill waste water ameliorate cognitive deficits and neuropathology.
Authors: Pantano D, Luccarini I, Nardiello P, Servili M, Stefani M, Casamenti F.
Journal: Br J Clin Pharmacol. 2017 Jan;83(1):54-62.
PMID: 27131215

In this study, the researchers tested the same genetically engineered mice, but with two different treatments:

  1.  Two much lower doses of oleuropein (4 and 100 times lower)
  2.  A mixture of polyphenols from olive mill concentrated waste water

The lowest dose of oleuropein (100 times less oleuropein than the previous study) did not provide any significant improvements for the mice, but the intermediate dose (only 4 times less oleuropein than the previous study) did provide significant benefits. These result indicate that there is a dose-dependent range to the beneficial properties of oleuropein.

The researchers also observed very similar beneficial effects from the mice drinking a mixture of polyphenols from olive mill concentrated waste water. Given these results, the investigators are now seeking to design appropriate conditions to perform a clinical trial to assess better the possible use of oleuropein (or a mix of olive polyphenols) against Alzheimer’s disease.

Ok, but what research has been done with oleuropein and Parkinson’s disease?

Unfortunately, not much.

A research group in Iran has looked at the effect of oleuropein in aged rodents and found an interesting result:

Iran
Title: Antioxidant role of oleuropein on midbrain and dopaminergic neurons of substantia nigra in aged rats.
Authors: Sarbishegi M, Mehraein F, Soleimani M.
Journal: Iran Biomed J. 2014;18(1):16-22.
PMID: 24375158                 (This article is OPEN ACCESS if you would like to read it)

In this study, the investigators took twenty aged rats (18-month-old) and randomly assigned them to two groups: a treatment group (which received a daily dose of 50 mg/kg of oleuropein for 6 months) and a control group (which received just water). Following these treatments, the investigators found an increase in the activity of anti-oxidant agents (such as superoxide dismutase, catalase and glutathione) in the treatment group compared to control group. The treated rats also had significantly more dopamine neurons in the region of the brain affected by Parkinson’s disease (the substantia nigra). The investigators concluded that oleuropein consumption in a daily diet may be useful in reducing oxidative stress damage by increasing the antioxidant activity in the brain.

This first study was followed more recently by a report from a group in Quebec (Canada) who investigated oleuropein use in a cell culture model of Parkinson’s disease:

Oleu
Title: Oleuropein Prevents Neuronal Death, Mitigates Mitochondrial Superoxide Production and Modulates Autophagy in a Dopaminergic Cellular Model.
Authors: Achour I, Arel-Dubeau AM, Renaud J, Legrand M, Attard E, Germain M, Martinoli MG.
Journal: Int J Mol Sci. 2016 Aug 9;17(8).
PMID: 27517912              (This article is OPEN ACCESS if you would like to read it)

The researcher conducting this study wanted to determine if oleuropein could prevent neuronal degeneration in a cellular model of Parkinson’s disease. They exposed cells to the neurotoxin 6-hydroxydopamine (6-OHDA) and then investigated mitochondrial oxidative stress and autophagy.

What is mitochondrial oxidative stress?

Mitochondria are the power house of each cell. They keep the lights on. Without them, the lights go out and the cell dies.

Mitochondria

Mitochondria and their location in the cell. Source: NCBI

Oxidative stress results from too much oxidation. Oxidation is the loss of electrons from a molecule, which in turn destabilises the molecule. Think of iron rusting. Rust is the oxidation of iron – in the presence of oxygen and water, iron molecules will lose electrons over time. Given enough time, this results in the complete break down of objects made of iron.

1112dp_01rust_bustingrusty_bottom_of_door

Rust, the oxidation of metal. Source: TravelwithKevinandRuth

The exact same thing happens in biology. Molecules in your body go through a similar process of oxidation – losing electrons and becoming unstable. This chemical reaction leads to the production of what we call free radicals, which can then go on to damage cells. A free radical is an unstable molecule – unstable because they are missing electrons.

imgres

How free radicals and antioxidants work. Source: h2miraclewater

In an unstable format, free radicals bounce all over the place, reacting quickly with other molecules, trying to capture the much needed electron to re-gain stability. Free radicals will literally attack the nearest stable molecule, to steal an electron. This leads to the “attacked” molecule becoming a free radical itself, and thus a chain reaction is started. Inside a living cell this can cause terrible damage, ultimately killing the cell.

Now if this oxidative process starts in the mitochondria, it can be very bad for a cell.

And what is autophagy?

Yes, the researchers also looked at autophagy levels in their cells. Autophagy is an absolutely essential function in a cell. Without autophagy, old proteins and mitochondria will pile up making the cell sick and eventually it dies. Through the process of autophagy, the cell can break down the old protein, clearing the way for fresh new proteins to do their job.

Think of autophagy as the waste disposal/recycling process of the cell.

Print

The process of autophagy. Source: Wormbook

Waste material inside a cell is collected in membranes that form sacs (called vesicles). These vesicles then bind to another sac (called a lysosome) which contains enzymes that will breakdown and degrade the waste material. The degraded waste material can then be recycled or disposed of by spitting it out of the cell.

Ok, so what did the researchers find?

Well, by pretreating the their cells with oleuropein 3 hours before exposing them to the neurotoxin, the investigators found a significant neuroprotective effect. There was a significant reduction in mitochondrial production of free radicals, and the investigators found an important role for oleuropein in the regulation of autophagy.

And the good news is that other research groups have observed similar beneficial effects of oleuropein in cell culture models of Parkinson’s disease (Click here to read more about that).

The bad news is: that is all the published research on oleuropein and Parkinson’s disease we could find (and we would be happy to be corrected on this if people are aware of other reports!).

So what does Oleuropein do in the brain?

This is a good question, but with so little research done in this area, it is hard to answer.

We know that oleuropein is well absorbed by the human body and that it is relatively stable (Click here to read more on this). In addition, it can cross the blood-brain-barrier – in rodents at least (Click here to read more on that).

Obviously (based on the research we described above), we know that oleuropein has anti-oxidant promoting activities. In addition, it appears to be doing something with regards to autophagy. And it may be regulating autophagy by acting as an inhibitor of mammalian target of rapamycin (mTOR) activation.

What is mTOR?

mTOR is a protein that binds with other proteins to form the nexus of a signalling pathway which integrates both intracellular and extracellular signals (such asnutrients, growth factors, and cellular energy status) and then serves as one of the central instructors of how the cell should respond.

For example, insulin can signal to mTOR the status of glucose levels in the body. mTOR also deals with infectious or cellular stress-causing agents, thus it could be involved in a cells response to conditions like Parkinson’s disease.

ncb2763-f11

Factors that activate mTOR. Source: Selfhacked

One important property of mTOR is its ability to block autophagy (the recycling process of the cell that we discussed above). Recently, the Italian researchers whose work we reviewed above, found that oleuropein can activate autophagy by blocking the mTOR pathway:

Onco

Title: Oleuropein aglycone induces autophagy via the AMPK/mTOR signalling pathway: a mechanistic insight.
Authors: Rigacci S, Miceli C, Nediani C, Berti A, Cascella R, Pantano D, Nardiello P, Luccarini I, Casamenti F, Stefani M.
Journal: Oncotarget. 2015 Nov 3;6(34):35344-57.
PMID: 26474288                (This article is OPEN ACCESS if you would like to read it)

The researchers conducting this study found that treatment with oleuropein caused an increase in autophagy in both cell culture and in a mouse model of Alzheimer’s disease, and they demonstrated that it achieved this by blocking the mTOR pathway.

Has anyone ever looked at oleuropein in the clinic?

No, not to our knowledge (and we are happy to be corrected on this).

There have been six clinical trials of olive leaf extract (the majority of which is oleuropien), but none of them have been focused on any neurological conditions.

 

So oleuropein is safe then?

It is a widely available supplement that a lot of people use to help lower bad cholesterol and blood pressure, so yes it can be considered safe. But any decision to experiment with oleuropein should only be made in consultation with your regular medically trained physician.

Why? Because there are always caveats.

Importantly, individuals with low blood pressure and diabetes may suffer even lower blood pressure and blood glucose levels as a result of consumption of oleuropein. Oleuropein may also interact with other pharmaceutical drugs that are designed to lower blood pressure or regulate diabetes. Such interactions could be dangerous.

And this is a particularly important factor for Parkinson’s disease as up to 30% of people with Parkinson’s may be glucose intolerant (Click here to see our post on Parkinson’s & diabetes).

Those who experience symptoms such as headache, nausea, flu-like symptoms, fainting, dizziness, and other life threatening symptoms should medical attention immediately.

What does it all mean?

We are grateful to regular reader (Don) who brought oleuropein to our attention. It is a very interesting chemical and we are definitely intrigued by it. We would certainly like to see more research on oleuropein in models of Parkinson’s disease.

Attentive readers will have noticed that most of the research discussed above have been conducted in the last 5-10 years. This suggests that oleuropein research is still in its infancy, particularly with regards to research on neurological conditions. And we hope that by reporting on it here, we will be bringing it to the attention of researchers.

Oleuropein is extracted from all parts of the olive tree (the leaves, bark, root, and fruit). It forms part of the defence system of the olive tree against stress or infection. Perhaps we could apply some of its interesting properties to Parkinson’s disease.


EDITORIAL NOTE:  Under absolutely no circumstances should anyone reading the material on this website consider it medical advice. The information provided here is for educational purposes only. Before considering or attempting any change in your treatment regime, PLEASE consult with your doctor or neurologist. While some of the drugs and supplements discussed on this website are clinically available, they may have serious side effects. We urge caution and professional consultation before altering any treatment regime. SoPD can not be held responsible for any actions taken based on the information provided here. 


The banner for this post was sourced from jrbenjamin

James: That essay

The-essay

In her excellent book – ‘The Enlightened Mr. Parkinson: The Pioneering Life of a Forgotten English Surgeon’ (Icon Books Ltd) – Dr Cherry Lewis wrote that the earliest reference to Mr James Parkinson’s ‘An Essay on the Shaking Palsy’ was an advert placed in the Morning Chronicle of Saturday 31st May (1817), under a list of books “published this day”.

Given this information, we searched the Britishnewspaperarchive online and captured the image presented above.

Today is the 200th anniversary of the publication of ‘An Essay on the Shaking Palsy’.

In this post, we continue our four part series on the man behind the disease by discussing the ‘Essay’ on the 200th anniversary of its publication.


waterloo_18june1817

The opening of Waterloo Bridge on the 18th of June 1817. Source: Thames

A few weeks before the opening of the Waterloo Bridge, James Parkinson published the booklet that would go on to immortalise him in the annals of medicine. An Essay on the Shaking Palsy, which spans 66 pages, was published by Sherwood, Neely and Jones of London, and printed by Whittingham and Rowland in 1817.

At the date of printing it sold for 3 shillings (approx. £9 or US$12).

Much has been written about the essay, and we here at the SoPD feel that we have little to actually add to the conversation. Thus our post today will simply provide an overview of the book (a highlights package, if you will), summarising it for those who do not have time to read its entirety (a full copy of the essay can be found by clicking here).

Essay

Source: Project Gutenberg

The Essay begins with a preface and is then divided into five chapters, labeled:

1. “DEFINITION—HISTORY—ILLUSTRATIVE CASES”

2. “PATHOGNOMONIC SYMPTOMS EXAMINED—TREMOR COACTUS—SCELOTYRBE FESTINANS”

3. “SHAKING PALSY DISTINGUISHED FROM OTHER DISEASES FROM WHICH IT MAY BE CONFOUNDED”

4. “PROXIMATE CAUSE—REMOTE CAUSES—ILLUSTRATIVE CASES”

5. “CONSIDERATIONS RESPECTING THE MEANS OF CURE”

The preface

In the preface of the book, James gave his reasons for actually writing it. Basically, he wanted to make others aware of what he considered a previously un-described condition.

At the heart of the preface is a paragraph, which reads:

“The disease is of long duration: to connect, therefore, the symptoms which occur in its later stages with those which mark its commencement, requires a continuance of observation of the same case, or at least a correct history of its symptoms, even for several years. Of both these advantages the writer has had the opportunities of availing himself; and has hence been led particularly to observe several other cases in which the disease existed in different stages of its progress. By these repeated observations, he hoped that he had been led to a probable conjecture as to the nature of the malady, and that analogy had suggested such means as might be productive of relief, and perhaps even of cure, if employed before the disease had been too long established. He therefore considered it to be a duty to submit his opinions to the examination of others, even in their present state of immaturity and imperfection.”

At the end of the preface, James hopes that friends to humanity and medical science…might be excited to extend their researches to this malady”. And in that situation James would “think himself fully rewarded by having excited the attention of those, who may point out the most appropriate means of relieving a tedious and most distressing malady”. 

Chapter 1

In the first chapter, James begins with a description of the Shaking Palsy (or ‘Paralysis agitans’ as he called it), that resembles modern Parkinson’s disease almost perfectly:

“Involuntary tremulous motion, with lessened muscular power, in parts not in action and even when supported; with a propensity to bend the trunk forwards, and to pass from a walking to a running pace: the senses and intellects being uninjured.”

He then moves on to provide a breakdown of the features that make up this condition, which includes a history of tremor that takes into account the works of Aelius “Galen” GalenusSylvius de la Boë, and Johann Juncker.

James starts by noting the slow progress of the condition:

“So slight and nearly imperceptible are the first inroads of this malady, and so extremely slow is its progress, that it rarely happens, that the patient can form any recollection of the precise period of its commencement. The first symptoms perceived are, a slight sense of weakness, with a proneness to trembling in some particular part; sometimes in the head, but most commonly in one of the hands and arms.”

How familiar does this sound?

And please remember, James was describing this condition for the first time based only on his own observations of just six individuals (three from a distance). His attention to detail was amazing, taking into account so many different aspects of the condition (from the obvious motor features to issues with bowel movements). And he noted it all down in the essay.

He continues by describing the progress of the condition over time:

“But as the malady proceeds,….The propensity to lean forward becomes invincible, and the patient is thereby forced to step on the toes and fore part of the feet, whilst the upper part of the body is thrown so far forward as to render it difficult to avoid falling on the face.”

His description took into account the entire history of the condition, starting from the appearance of the first features and finishing with the late stages of the disease:

“As the disease proceeds towards its last stage, the trunk is almost permanently bowed, the muscular power is more decidedly diminished, and the tremulous agitation becomes violent….As the debility increases and the influence of the will over the muscles fades away, the tremulous agitation becomes more vehement. It now seldom leaves him for a moment;”

After describing the basic clinical appearance of the condition, James then immediately moves on to each of the six cases he based his description on.

Case I was the first encounter of this condition for James. It was also probably one of the case that James was most familiar with as he wrote “every circumstance occurred which has been mentioned in the preceding history”. In his writing of Case I, however, James was rather brief:

Case I

“The subject of this case was a man rather more than fifty years of age, who had industriously followed the business of a gardener, leading a life of remarkable temperance and sobriety. The commencement of the malady was first manifested by a slight trembling of the left hand and arm, a circumstance which he was disposed to attribute to his having been engaged for several days in a kind of employment requiring considerable exertion of that limb. Although repeatedly questioned, he could recollect no other circumstance which he could consider as having been likely to have occasioned his malady.”

The “next case” (as James wrote it, indicating that the cases are presented in chronological order), Case II, was a man that James casually met with in the street.

Case II

“It was a man sixty-two years of age; the greater part of whose life had been spent as an attendant at a magistrate’s office. He had suffered from the disease about eight or ten years. All the extremities were considerably agitated, the speech was very much interrupted, and the body much bowed and shaken. He walked almost entirely on the fore part of his feet, and would have fallen every step if he had not been supported by his stick. He described the disease as having come on very gradually,…”

Case II attributed his condition to his choice of lifestyle (“irregularities in mode of living and indulgence in spiritous liquors,”), which James did not give any credit. This was probably because much of the rest of the city partook in such a lifestyle without the emergence of the disease. Ever the humanitarian, though, James points towards the unfortunate situation that these individuals found themselves:

“He was the inmate of a poor-house of a distant parish, and being fully assured of the incurable nature of his complaint, declined making any attempts for relief.”

The third case was also “noticed casually in the street“. James did interact with the man though, determining that he had been a sailor who attributed his condition to having been for many months in a Spanish prison:

Case III.

“The subject…was a man of about sixty-five years of age, of a remarkable athletic frame. The agitation of the limbs, and indeed of the head and of the whole body, was too vehement to allow it to be designated as trembling. He was entirely unable to walk; the body being so bowed, and the head thrown so forward, as to oblige him to go on a continued run, and to employ his stick every five or six steps to force him more into an upright posture, by projecting the point of it with great force against the pavement.”

The 4th case was a gentleman (of about fifty-five years of age) who presented himself to James. He claimed that he had first experienced the trembling of the arms about five years before. In this case, we see the nature of the medical treatments during that period (that being a preference for blood letting):

Case IV.

“His application was on account of a considerable degree of inflammation over the lower ribs on the left side, which terminated in the formation of matter beneath the fascia. About a pint was removed on making the necessary opening; and a considerable quantity discharged daily for two or three weeks. On his recovery from this, no change appeared to have taken place in his original complaint; and the opportunity of learning its future progress was lost by his removal to a distant part of the country”

Case V was the subject that James had the least amount of information about and observed the gentleman only from a distance (it is curious to note that all of these cases were males – who have a higher risk of developing Parkinson’s disease – click here for more on this):

Case V.

“…one of the characteristic symptoms of this malady, the inability for motion, except in a running pace, appeared to exist in an extraordinary degree. It seemed to be necessary that the gentleman should be supported by his attendant, standing before him with a hand placed on each shoulder, until, by gently swaying backward and forward, he had placed himself in equipoise; when, giving the word, he would start in a running pace, the attendant sliding from before him and running forward, being ready to receive him and prevent his falling, after his having run about twenty paces”

Case VI may have been the individual that spurred James to write his essay as it was one “which presented itself to observation since those above-mentioned,”. Thus, James had the benefit of hindsight and all the information that he had gained from the previous cases, when he was confronted with Case VI and he could make a thorough study of the individual. In case VI, James also hints at the indiscriminate nature of the condition, afflicting people from all sorts of backgrounds.

Case VI.

“The gentleman who was the subject of it is seventy-two years of age. He has led a life of temperance, and has never been exposed to any particular situation or circumstance which he can conceive likely to have occasioned, or disposed to this complaint; which he rather seems to regard as incidental upon his advanced age, than as an object of medical attention….About eleven or twelve, or perhaps more, years ago, he first perceived weakness in the left hand and arm, and soon after found the trembling commence. In about three years afterwards the right arm became affected in a similar manner: and soon afterwards the convulsive motions affected the whole body, and began to interrupt the speech…Of late years the action of the bowels had been very much retarded;…”

James notes with Case VI that the gentleman had the capacity to temporarily control his situation by his own will:

“…he, being then just come in from a walk, with every limb shaking, threw himself rather violently into a chair, and said, ‘Now I am as well as ever I was in my life.’ The shaking completely stopped; but returned within two minutes”

At the end of the section on CaseVI, James notes some input from the wife of the gentleman:

“…if whilst walking he felt much apprehension from the difficulty of raising his feet, if he saw a rising pebble in his path? he avowed, in a strong manner, his alarm on such occasions; and it was observed by his wife, that she believed, that in walking across the room, he would consider as a difficulty the having to step over a pin”

Having finished reading Chapter 1, it is truly remarkable to recall that James was describing what he thought was a previously unrecognised condition. Remarkable because of the depth and scope he provides. It is difficult to put oneself in his shoes, given that we are now so familiar with the disease. But it does Mr Parkinson great credit both as a surgeon and a writer that what he is describing feels so familiar.

Chapter 2

Here James returns to the cardinal features of the condition as he sees them, starting with the tremor:

1. Involuntary tremulous motion, with lessened voluntary muscular power, in parts, not in action, and even supported.

In this first section, James breaks down the different types of tremor in an effort to better understand this condition he is describing.

“It is necessary that the peculiar nature of this tremulous motion should be ascertained, as well for the sake of giving to it its proper designation, as for assisting in forming probable conjectures, as to the nature of the malady, which it helps to characterise”

And again, James cites the works of Galen and Sylvius de la Boë.

galen-1

Galen. Source: thefamouspeople

“The separation of palpitation of the limbs (Palmos of Galen, Tremor Coactus of de la Boë) from tremor, is the more necessary to be insisted on, since the distinction may assist in leading to a knowledge of the seat of the disease.”

Sylviusf

de la Boë. Source: Wikipedia

James concludes that the tremor associated with his new condition is distinct given that the tremor is nearly constant or “induced immediately on bringing the parts into action”

The second characteristic feature of this newly described condition, according to James, is the gait and posture:

2. A propensity to bend the trunk forwards, and to pass from a walking to a running pace.

Here James discusses the works of François Boissier de Sauvages de Lacroix (1706 – 1767), a French physician and botanist who is credited with establishing a methodical nosology for diseases (a classification system).

boissier01

de Sauvage. Source: Homeoint

“Mons. de Sauvages attributes this complaint to a want of flexibility in the muscular fibres. Hence, he supposes, that the patients make shorter steps, and strive with a more than common exertion or impetus to overcome the resistance; walking with a quick and hastened step, as if hurried along against their will”

It is a demonstration of Mr Parkinson’s studious nature and high general level of intelligence that he was so familiar with the works of de Sauvage – it is a simple task for us modern folk to simply ‘google’ anything we don’t know or are curious about. Where did James go to find his background research for his Esssay?

Having clearly outlined the features of the condition, James next moves to Chapter 3 where he attempts to differentiate this condition from other maladies.

Chapter 3

James did not want to have this new condition he was describing confused with other diseases, hence the meticulous description of the symptoms/features.

“…it is necessary to show that it is a disease which does not accord with any which are marked in the systematic arrangements of nosologists; and that the name by which it is here distinguished has been hitherto vaguely applied to diseases very different from each other, as well as from that to which it is now appropriated”

James’ choice of name for the new condition was ‘Shaking palsy’, but he noted that this label had been used several times before. For example, one Dr. Charlton had used the label in describing a particular case:

“Another case, which the Doctor designates as ‘A Shaking Palsy,’ apparently from worms, he describes thus, “A poor boy, about twelve or thirteen years of age, was seized with a Shaking Palsy. His legs became useless, and together with his head and hands, were in continual agitation; after many weeks trial of various remedies, my assistance was desired…His bowels being cleared, I ordered him a grain of Opium a day in the gum pill; and in three or four days the shaking had nearly left him.” By pursuing this plan, the medicine proving a vermifuge, he could soon walk, and was restored to perfect health”

Given the level of detail that James goes into in other chapters, it is fair to say that chapter 3 is light reading. But it finishes strong as James describes the truly distinguishing feature of his version of Shaking palsy – that being the resting state nature of the tremor:

“If the trembling limb be supported, and none of its muscles be called into action, the trembling will cease. In the real Shaking Palsy the reverse of this takes place, the agitation continues in full force whilst the limb is at rest and unemployed;”

And it was this feature for James that could be used to distinguish it from other conditions.

Chapter 4

In Chapter 4, James tries to understand the cause of the condition, but right up front he acknowledges that this is a rather difficult task:

“Unaided by previous inquiries immediately directed to this disease, and not having had the advantage, in a single case, of that light which anatomical examination yields, opinions and not facts can only be offered”

In addition, James notes that “Cases illustrative of the nature and cause of this malady are very rare”

He does an admirable job in his endeavour here, however, by looking at previously reported cases of other diseases that share some similarities with this new condition. And James actually describes cases that he himself has dealt with (albeit by informally), but he takes pains to point out that these cases are different to the new conditions that he is describing in this essay. For example:

“…the unhappy subject of this malady was casually met in the street, shifting himself along, seated in a chair; the convulsive motions having ceased, and the limbs having become totally inert, and insensible to any impulse of the will”

In this case, the man had been treated with mercury for a venereal infection (click here to read more about early mercury treatments) many years before, which had left him with convulsive movements restricted to the legs.

Using this case study approach, however, James proposes that the disease is targeting or affecting an area of the brain stem called the medulla oblongata (which is affected in Parkinson’s disease, and is actually not too far from the midbrain where the significant loss of the dopamine neurons gives rise to the motor features of Parkinson’s disease).

1311_Brain_Stem

Location of the midbrain and medulla in the human brain. Source: Wikipedia

Chapter 5

In chapter 5, James expresses hope that a successful treatment is almost at hand:

“…there appears to be sufficient reason for hoping that some remedial process may ere long be discovered, by which, at least, the progress of the disease may be stopped”

Exactly 200 years on, I think it is fair to say that James was a bit too optimistic in nature, but we are certainly a lot closer now to stopping the disease than he was then.

James was instructive in how he thought it was best to attack the condition. He divides the condition into two halves, early and late, based on the spread of the motor features from individual limbs to other areas of the body. And he is rather certain that early diagnosis was essential if there was to be any chance of cure.

He also thought that the condition simply required some reverse engineering:

“…it seems as if we were able to trace the order and mode in which the morbid changes may proceed in this disease”

But his thoughts on how to treat the disease were largely based on the medical practises of the time (as they are today):

“…blood should be first taken from the upper part of the neck,…After which vesicatories should be applied to the same part, and a purulent discharge obtained by appropriate use of the Sabine Liniment; having recourse to the application of a fresh blister, when from the diminution of the discharging surface, pus is not secreted in a sufficient quantity”

He provides further thoughts on this treatment, but then offers the caveat that this is merely an opinion:

“Until we are better informed respecting the nature of this disease, the employment of internal medicines is scarcely warrantable;”

James also then comments on the insidious nature and the slow progress of the disease, as it:

“Seldom occurring before the age of fifty, and frequently yielding but little inconvenience for several months, it is generally considered as the irremediable diminution of the nervous influence, naturally resulting from declining life; and remedies therefore are seldom sought for”

And this leaves the sufferer focusing on:

“The weakened powers of the muscles in the affected parts is so prominent a symptom, as to be very liable to mislead the inattentive, who may regard the disease as a mere consequence of constitutional debility. If this notion be pursued, and tonic medicines, and highly nutritious diet be directed, no benefit is likely to be thus obtained; since the disease depends not on general weakness, but merely on the interruption of the flow of the nervous influence to the affected parts”

This is very insightful of James. He understood that it was not the weakness felt in the muscles that was paramount in this condition, but rather a dysfunction in the brain.

He concludes the essay with the following:

“To such researches the healing art is already much indebted for the enlargement of its powers of lessening the evils of suffering humanity. Little is the public aware of the obligations it owes to those who, led by professional ardour, and the dictates of duty, have devoted themselves to these pursuits, under circumstances most unpleasant and forbidding. Every person of consideration and feeling, may judge of the advantages yielded by the philanthropic exertions of a Howard; but how few can estimate the benefits bestowed on mankind, by the labours of a Morgagni, Hunter, or Baillie.

FINIS.”

Regarding the last line, I may be displaying my ignorance here with regards to ‘a Howard’, but I suspect James is referring to John Howard (1726 – 1790), an English philanthropist of James’ era:

800px-John_Howard_by_Mather_Brown

John Howard. Source: Wikipedia

Although, “a Howard” is also an old slang term used to describe a man (any man) of great character!

Giambattista_morgagni

Giovanni Battista MorgagniSource: Wikipedia

Giovanni Battista Morgagni (1682 – 1771) was an Italian anatomist, who is generally regarded as the father of modern anatomical pathology.

280px-John_Hunter_by_John_Jackson

John Hunter. Source: Wikipedia

John Hunter (1728 – 1793) was a Scottish surgeon – one of the most distinguished scientists/surgeons of his day. He was an early advocate of careful observation and scientific method in medicine, and James personally learned a great deal from him. Between October 1785 and April 1786, James attended the evening lectures provided by Hunter. James wrote down the lectures verbatim (in shorthand) and his notes were later published by his son John (“Hunterian Reminiscences, Being The Substance Of A Course Of Lectures On The Principles And Practice Of Surgery Delivered By John Hunter In The Year 1785″ – a precious resource given that Hunter’s own notes were later destroyed by fire).

Matthew Baille FRS (1761-1823)

Matthew BaillieSource: Wikipedia

Matthew Baillie was another Scottish physician and pathologist. A pupil of his uncle, John Hunter (above), Ballie provided us with the first systematic study of pathology. James was certainly familiar with Ballie, as he cited his works.


For further reading on An Essay on the Shaking Palsy we recommend a review written by Prof Brian Hurwitz (King’s College London) called Urban Observation and Sentiment in James Parkinson’s Essay on the Shaking Palsy (1817) which provides fantastic insight into James, the age he lived in, the essay itself, and the reception of the essay (Click here to read that review).

This post was written in observation of the 200 year anniversary of the publishing of the Essay on the Shaking Palsy. It is part two in a four part series on the life of Mr James Parkinson (click here for part one). In the third instalment, we will look at his life’s work, before the fourth part looks at his final years and his legacy.


The banner for today’s post was sourced from the Britishnewspaperarchive

A connection between ALS & Parkinson’s disease? Oh’ll, SOD it!

604ee0d6431dbd15f686133f6fa7205c

Please excuse our use of UK slang in the title of this post, but a group of Australian researchers have recently discovered something really interesting about Parkinson’s disease.

And being a patriotic kiwi, it takes something REALLY interesting for me to even acknowledge that other South Pacific nation. This new finding, however, could be big.

In today’s post, we will review new research dealing with a protein called SOD1, and discuss what it could mean for the Parkinson’s community.


d1ea3d21c36935b85043b3b53f2edb1f87ab7fa6

The number of dark pigmented dopamine cells in the substantia nigra are reduced in the Parkinson’s disease brain (right). Source: Adaptd from Memorangapp

Every Parkinson’s-associated website and every Parkinson’s disease researchers will tell you exactly the same thing when describing the two cardinal features in the brain of a person who died with Parkinson’s disease:

  1. The loss of certain types of cells (such as the dopamine producing cells of the substantia nigra region of the brain – see the image above)
  2. The clustering (or aggregation) of a protein called Alpha synuclein in tightly packed, circular deposits, called Lewy bodies (see image below).

9-lb2

A Lewy body inside a cell. Source: Adapted from Neuropathology-web

The clustered alpha synuclein protein, however, is not limited to just the Lewy bodies. In the affected areas of the brain, aggregated alpha synuclein can be seen in the branches of cells – see the image below where alpha synuclein has been stained brown on a section of brain from a person with Parkinson’s disease.

Lewy_neurites_alpha_synuclein

Examples of Lewy neurites (indicated by arrows). Source: Wikimedia

Now, one of the problems with our understanding of Parkinson’s disease is disparity between the widespread presence of clustered alpha synuclein and very selective pattern of cell loss. Alpha synuclein aggregation can be seen distributed widely around the affected areas of the brain, but the cell loss will be limited to specific populations of cells.

If the disease is killing a particular population of cells, why is alpha synuclein clustering so wide spread?

So why is there a difference?

We don’t know.

It could be that the cells that die have a lower threshold for alpha synuclein toxicity (we discussed this is a previous post – click here?).

But this question regarding the difference between these two features has left many researchers wondering if there may be some other protein or agent that is actually killing off the cells and then disappearing quickly, leaving poor old alpha synuclein looking rather guilty.

maxresdefault

Poor little Mr “A Synuclein” got the blame, but his older brother actually did it! Source: Youtube

And this is a very serious discussion point.

This year of 2017 represents the 200th anniversary of James Parkinson’s first description of Parkinson’s disease, but it also represents the 20th anniversary since the association between alpha synuclein and PD was first established. We have produced almost 7,000 research reports on the topic of alpha synuclein and PD during that time, and we currently have ongoing clinical trials targetting alpha synuclein.

But what if our basic premise – that alpha synuclein is the bad guy – is actually wrong?

Is there any evidence to suggest this?

We are just speculating here, but yes there is.

For example, in a study of 904 brains, alpha synuclein deposits were observed in 11.3% of the brains (or 106 cases), but of those cases only 32 had been diagnosed with a neurodegenerative disorder (Click here to read more on this). The remaining 74 cases had demonstrated none of the clinical features of Parkinson’s disease.

So what else could be causing the cell death?

Well, this week some scientists from sunny Sydney (Australia) reported a protein that could fit the bill.

sydney_cruises

Sydney. Source: Vagabond

The interesting part of their finding is that the protein is also associated with another neurodegenerative condition: Amyotrophic lateral sclerosis.

Remind me again, what is Amyotrophic lateral sclerosis?

Parkinson’s disease and Amyotrophic lateral sclerosis (ALS) are the second and third most common adult-onset neurodegenerative conditions (respectively) after Alzheimer’s disease. We recently discussed ALS in a previous post (Click here to read that post).

ALS, also known as Lou Gehrig’s disease and motor neuron disease, is a neurodegenerative condition in which the neurons that control voluntary muscle movement die. The condition affects 2 people in every 100,000 each year, and those individuals have an average survival time of two to four years.

You may have heard of ALS due to it’s association with the internet ‘Ice bucket challenge‘ craze that went viral in 2014-15.

ice-bucket-challenge

The Ice bucket challenge. Source: Forbes

What is the protein associated with ALS?

In 1993, scientists discovered that mutations in the gene called SOD1 were associated with familial forms of ALS (Click here to read more about this). We now know that mutations in the SOD1 gene are associated with around 20% of familial cases of ALS and 5% of sporadic ALS.

The SOD1 gene produces an enzyme called Cu-Zn superoxide dismutase.

This enzyme is a very powerful antioxidant that protects the body from damage caused by toxic free radical generated in the mitochondria.

Protein_SOD1_PDB_1azv

SOD1 protein structure. Source: Wikipedia

One important note here regarding ALS: the genetic mutations in the SOD1 gene do not cause ALS by affecting SOD1’s antioxidant properties (Click here to read more about this). Rather, researchers believe that the cell death seen in SOD1-associated forms of ALS is the consequences of some kind of toxic effect caused by the mutant protein.

So what did the Aussie researchers find about SOD1 in Parkinson’s disease?

This week, the Aussie researchers published this research report:

SOD
Title: Amyotrophic lateral sclerosis-like superoxide dismutase 1 proteinopathy is associated withneuronal loss in Parkinson’s disease brain.
Authors: Trist BG, Davies KM, Cottam V, Genoud S, Ortega R, Roudeau S, Carmona A, De Silva K, Wasinger V, Lewis SJG, Sachdev P, Smith B, Troakes C, Vance C, Shaw C, Al-Sarraj S, Ball HJ, Halliday GM, Hare DJ, Double KL.
Journal: Acta Neuropathol. 2017 May 19. doi: 10.1007/s00401-017-1726-6.
PMID: 28527045

Given that oxidative stress is a major feature of Parkinson’s disease, the Aussie researchers wanted to investigate the role of the anti-oxidant enzyme, SOD1 in this condition. And what they found surprised them.

Heck, it surprised us!

Two areas affected by Parkinson’s disease – the substantia nigra (where the dopamine neurons reside; SNc in the image below) and the locus coeruleus (an area in the brain stem that is involved with physiological responses to stress; LC in the image below) – exhibited little or no SOD1 protein in the control brains.

But in the Parkinsonian brains, there was a great deal of SOD1 protein (see image below).

401_2017_1726_Fig1_HTML

SO1 staining in PD brain and Control brains. Source: Springer

In the image above, you can see yellowish-brown stained patches in both the PD and control images. This a chemical called neuromelanin and it can be used to identify the dopamine-producing cells in the SNc and LC. The grey staining in the PD images (top) are cells that contain SOD1. Note the lack of SOD1 (grey staining) in the control images (bottom).

Approximately 90% of Lewy bodies in the Parkinson’s affected brains contained SOD1 protein. The investigators did report that the levels of SOD1 protein varied between Lewy bodies. But the clustered (or ‘aggregated’) SOD1 protein was not just present with alpha synuclein, often it was found by itself in the degenerating regions.

The researchers occasional saw SOD1 aggregation in regions of age-matched control brains, and they concluded that a very low level of SOD1 must be inherent to the normal ageing process.

But the density of SOD1 clustering was (on average) 8x higher in the SNc and 4x higher in the LC in the Parkinsonian brain compared to age-matched controls. In addition, the SOD1 clustering was significantly greater in these regions than all of the non-degenerating regions of the same Parkinson’s disease brains.

The investigators concluded that these data suggest an association between SOD1 aggregation and neuronal loss in Parkinson’s disease. Importantly, the presence of SOD1 aggregations “closely reflected the regional pattern of neuronal loss”.

They also demonstrated that the SOD1 protein in the Parkinsonian brain was not folded correctly, a similar characteristic to alpha synuclein. A protein must fold properly to be able to do it’s assigned jobs. By not folding into the correct configuration, the SOD1 protein could not do it’s various functions – and the investigators observed a 66% reduction in SOD1 specific activity in the SNc of the Parkinson’s disease brains.

Interestingly, when the researchers looked at the SNc and LC of brains from people with ALS, they identified SOD1 aggregates matching the SOD1 clusters they had seen in these regions of the Parkinson’s disease brain.

Is this the first time SOD1 has been associated with Parkinson’s disease?

No, but it is the first major analysis of postmortem Parkinsonian brains. SOD1 protein in Lewy bodies has been reported before:

1995

Title: Cu/Zn superoxide dismutase-like immunoreactivity is present in Lewy bodies from Parkinson disease: a light and electron microscopic immunocytochemical study
Authors: Nishiyama K, Murayama S, Shimizu J, Ohya Y, Kwak S, Asayama K, Kanazawa I.
Journal: Acta Neuropathol. 1995;89(6):471-4.
PMID: 7676802

The investigators behind this study reported SOD1 protein was present in Lewy bodies, in the substantia nigra and locus coeruleus of brains from five people with Parkinson’s disease. Interestingly, they showed that SOD1 is present in the periphery of the Lewy body, similar to alpha synuclein. Both of these protein are present on the outside of the Lewy body, as opposed to another Parkinson’s associated protein, Ubiquitin, which is mainly present in the centre (or the core) of Lewy bodies (see image below).

Lewy-bodies

A more recent study also demonstrated SOD1 protein in the Parkinsonian brain, including direct interaction between SOD1 and alpha synuclein:

Alspha

Title: α-synuclein interacts with SOD1 and promotes its oligomerization
Authors: Helferich AM, Ruf WP, Grozdanov V, Freischmidt A, Feiler MS, Zondler L, Ludolph AC, McLean PJ, Weishaupt JH, Danzer KM.
Journal: Mol Neurodegener. 2015 Dec 8;10:66.
PMID: 26643113              (This article is OPEN ACCESS if you would like to read it)

These researchers found that alpha synuclein and SOD1 interact directly, and they noted that Parkinson’s disease related mutations in alpha synuclein (A30P, A53T) and ALS associated mutation in SOD1 (G85R, G93A) modify the binding of the two proteins to each other. They also reported that alpha synuclein accelerates SOD1 aggregation in cell culture. This same group of researchers published another research report last year in which they noted that aggregated alpha synuclein increases SOD1 clustering in a mouse model of ALS (Click here for more on this).

We should add that alpha synuclein aggregations in ALS are actually quite common (click here and here to read more on this).

Are there any genetic mutations in the SOD1 gene that are associated with Parkinson’s disease?

Two studies have addressed this question:

genes

Title: Sequence of the superoxide dismutase 1 (SOD 1) gene in familial Parkinson’s disease.
Authors: Bandmann O, Davis MB, Marsden CD, Harding AE.
Journal: J Neurol Neurosurg Psychiatry. 1995 Jul;59(1):90-1.
PMID: 7608718                   (This article is OPEN ACCESS if you would like to read it)

And then in 2001, a second analysis:

Genes2

Title: Genetic polymorphisms of superoxide dismutase in Parkinson’s disease.
Authors: Farin FM, Hitosis Y, Hallagan SE, Kushleika J, Woods JS, Janssen PS, Smith-Weller T, Franklin GM, Swanson PD, Checkoway H.
Journal: Mov Disord. 2001 Jul;16(4):705-7.
PMID: 11481695

Both studies found no genetic variations in the SOD1 gene that were more frequent in the Parkinson’s affected community than the general population. So, no, there are no SOD1 genetic mutations that are associated with Parkinson’s disease.

Are there any treatments targeting SOD1 that could be tested in Parkinson’s disease?

Great question. Yes there are. And they have already been tested in models of PD:

als

Title: The hypoxia imaging agent CuII(atsm) is neuroprotective and improves motor and cognitive functions in multiple animal models of Parkinson’s disease.
Authors: Hung LW, Villemagne VL, Cheng L, Sherratt NA, Ayton S, White AR, Crouch PJ, Lim S, Leong SL, Wilkins S, George J, Roberts BR, Pham CL, Liu X, Chiu FC, Shackleford DM, Powell AK, Masters CL, Bush AI, O’Keefe G, Culvenor JG, Cappai R, Cherny RA, Donnelly PS, Hill AF, Finkelstein DI, Barnham KJ.
Title: J Exp Med. 2012 Apr 9;209(4):837-54.
PMID: 22473957               (This article is OPEN ACCESS if you would like to read it)

CuII(atsm) is a drug that is currently under clinical investigation as a brain imaging agent for detecting hypoxia (damage caused by lack of oxygen – Click here to read more about this).

The researchers conducting this study, however, were interested in this compound for other reasons: CuII(atsm) is also a highly effective scavenger of a chemical called ONOO, which can be very toxic. CuII(atsm) not only inhibits this toxicity, but it also blocks the clustering of alpha synuclein. And given that CuII(atsm) is capable of crossing the blood–brain barrier, these investigators wanted to assess the drug for its ability to rescue model of Parkinson’s disease.

And guess what? It did!

And not just in one model of Parkinson’s disease, but FOUR!

The investigators even waited three days after giving the neurotoxins to the mice before giving the CuII(atsm) drug, and it still demonstrated neuroprotection. It also improved the behavioural features of these models of Parkinson’s disease.

Is CuII(atsm) being tested for anything else in Clinical trials?

Yes, there is a clinical trial ongoing for ALS in Australia.

The Phase I study, being run by Collaborative Medicinal Development Pty Limited, is a dose escalating study of Cu(II)ATSM to determine if this drug is safe for use in ALS (Click here for more on this study).

static1.squarespace

Cu(II)ATSM is an orally administered drug that inhibits the activity of misfolded SOD1 protein. It has been shown to paradoxically increase mutant SOD1 protein in a mouse model of ALS, but it also provides neuroprotection and improves the outcome for these mice (Click here to read more on this).

If this trial is successful, it would be interesting to test this drug on a cohort of people with Parkinson’s disease. Determining which subgroup of the Parkinson’s affected community would most benefit from this treatment is still to be determined. There is some evidence published last year that suggests people with genetic mutations in the Parkinson’s associated gene PARK2 could benefit from the approach (Click here to read more on this). More research, however, is needed in this area.

So what does it all mean?

Right, so summing up, a group of Australian researchers have reported that the ALS associated protein SOD1 is closely associated with the cell death that we observe in the brains of people with Parkinson’s disease.

They suggest that this could highlight a common mechanisms of toxic SOD1 aggregation in both Parkinson’s disease and ALS. Individuals within the Parkinson’s affected community do not appear to have any genetic mutations in the SOD1 gene, which makes this finding is very interesting.

What remains to be determined is whether SOD1 aggregation is a “primary pathological event”, or if it is secondary to some other disease causing agent. We are also waiting to see if a clinical trial targeting SOD1 in ALS is successful. If it is, there may be good reasons for targeting SOD1 as a novel treatment for Parkinson’s disease.


The banner for today’s post was sourced from Pinterest

Sar-gram-o-stim: The immunostimulation of Parkinson’s disease

Cancer-Killing T-Cells

A major trend in experimental medicine at present is ‘immunotherapy‘ – stimulating or reprogramming the immune system to help fight particular diseases.

A research group in Nebraska have attempted to use this approach for Parkinson’s disease, and recently they have published some very interesting clinical trial results.

In today’s post, we will discuss the science and review the results of their research.


IMG_0689-Nebraska-sign

Nebraska. Source: The Toast

Here at the SoPD HQ, we like surprises.

And when several readers contacted us about some interesting results from a new clinical trial for Parkinson’s disease that we knew nothing about, we were rather ‘OMG! What a fantastic surprise!’ about it.

The results stem from a clinical trial that has taken a rather different approach to tackling Parkinson’s disease: boosting the immune system to help fight off the condition. And rather than simply covering up the symptoms, the drug being tested may actually slow down the condition.

You may have heard about this trial as the results of this clinical study have attracted the attention of the media:

So what was the new clinical trial all about?

Let’s start with the context of the study. You see, it took place in the great US state of Nebraska.

Interesting place Nebraska.

1200px-Nebraska_in_United_States.svg

Nebraska (in red). Source: Wikipedia

The birth place of actors Fred Astaire and Marlon Brando.

And home to the largest porch swing in the world (holds 18 adults or 24 children – amazing).

Swing

The world’s largest swing chair. Source: Pinterest

Nebraska is also one of the top agricultural states in the USA, with about 93% of the land being used for farming. And approximately 40% of the state’s population (750,000 out of 1.8 million) lives in those rural areas. As a result of this largely rural population, there are probably a lot of people in Nebraska being exposed to pesticide and insecticides (in the air they breath and the water they drink).

This exposure is believed to be one of the reasons why Nebraska has one of the highest rates of Parkinson’s disease in the USA.

There are approximately 330 people per 100,000 of the general population living with Parkinson’s Disease in Nebraska (Click here for more on this). Compare that with just 180 people per 100,000 of the UK general population having Parkinson’s Disease (Click here for more on this).

As a result of this statistic, Parkinson’s disease is taken very seriously in Nebraska.

Back in 1996, Nebraska became the first state to create a Parkinson’s disease registry. They also have tremendous support groups for the Parkinson’s community (such as Parkinson’s Nebraska). 

1ntJMZz3

There is also a lot of Parkinson’s disease research being conducted there.

And this brings us to the clinical study results we are going to discuss:

Sargramostim

Title:Evaluation of the safety and immunomodulatory effects of sargramostim in a randomized, double-blind phase 1 clinical Parkinson’s disease trial
Authors: Gendelman HE, Zhang Y, Santamaria P, Olson KE, Schutt CR, Bhatti D, Shetty BLD, Lu Y, Estes KA, Standaert DG, Heinrichs-Graham E, Larson L, Meza JL, Follett M, Forsberg E, Siuzdak G, Wilson TW, Peterson C, & Mosley RL
Journal: npj Parkinson’s Disease (2017) 3, 10.
PMID: N/A                   (This article is OPEN ACCESS if you would like to read it)

For this randomised, double-blind phase 1 clinical trial, the researchers enrolled 20 people with Parkinson’s disease and 17 age-matched non-Parkinsonian control subjects. The people with Parkinson’s disease ranged in age from 53 to 76 years (mean age of 64) and they had had symptoms for 3–14 years (the mean was 7 years). Both the Parkinson’s disease group and control group were monitored for 2 months before the trial started in order to establish baseline measurements and profiles.

The Parkinson’s disease group were then randomly assigned into two equal sized groups (10 subjects each) and they were then self-administered (by self-injection) either sargramostim (6 μg/kg/day) or a placebo control solution (saline) for 56 days (click here to see the details of the clinical trial).

Hang on a second, what is Sargramostim?

Sargramostim (marketed by the pharmaceutical company Genzyme under the tradename ‘Leukine’) is an Food and Drug Administration (FDA) -approved recombinant granulocyte macrophage colony-stimulating factor (GM-CSF) that functions as an immunostimulator.

What…on earth…..does any of that….actually mean?

Ok, so Food and Drug Administration (FDA) -approved means that this drug is safe to use in humans. Sargramostim is currently widely used in bone marrow transplantation procedures, to stimulate the production of new blood cells.

Recombinant‘ basically means that we are talking about an artificially produced protein.

Granulocyte macrophage colony-stimulating factor‘ is an actual protein that our bodies produce. GM-CSF is a small protein that is secreted by various types of cells in our body, and it functions as a cytokine. And yes, I know what you are going to ask:

What’s a cytokine?

Cytokines (from the Greek: kýtos meaning ‘container, body, cell’; and kī́nēsis meaning ‘movement’) are small proteins that are secreted by certain cells in the body and they have an effect on other cells. Cytokines are a method of communication for cells.

figure_12-01a

How cytokines work. Source: SBS

Granulocyte macrophage colony-stimulating factor is secreted by various cells around the body to communicate with the immune system that something is wrong. In it’s actually function, GM-CSF acts as a white blood cell growth factor, or a stimulant of white blood cell production.

e2e67f_0d0f5a687dd94122ad1773c579524022-mv2.gif_srz_450_338_85_22_0.50_1.20_0

GM-CSF stimulates blood stem cells into production. Source: Oxymed

Why are white blood cells important?

While red blood cells are principally involved with the delivery of oxygen to the various parts of the body, the white blood cells (also referred to as leukocytes or leucocytes), are the cells of your immune system that protect your body against both infectious disease and foreign invaders.

CDR0000503952-1

6 types of white blood cells. Source: Stfranciscare

GM-CSF stimulates blood stem cells to produce more neutrophils, eosinophils, basophils, and monocytes (all types of white blood cells – see image above). Monocytes then migrate towards the tissue affected by the injury or disease, where they then mature into macrophages and dendritic cells (Macrophages are large, specialised cells that are responsible for removing damaged target cells).

Once at the site of trouble, macrophages produce pro-inflammatory neurotoxins that help to destroy unhealthy or damaged cells, making them easier to engulf and dispose of. The problem is that those released neurotoxins can also damage surrounding healthy cells.

Given that GM-CSF stimulates this kind of activity, you are probably wondering why researchers would be giving Sargramostim to folks with Parkinson’s disease.

But GM-CSF also does something else that is really interesting:

GM-CSF stimulates regulatory T (Treg) cells. 

What are regulatory T cells?

Regulatory T (Treg) cells maintain order in the immune system. They do this by enforcing a dominant negative regulation on other immune cells, particularly other T-cells.

T-cells are a type of white blood cell that circulate around our bodies, scanning for cellular abnormalities and infections.

Think of T-cells as the inquisitive neighbours curious about and snooping around a local crime scene, and then imagine that Treg cells are the police telling them “nothing to see here, move along”.

Regulatory_T_Cell-smaller

Tregs maintaining order. Source: Keywordsuggestions

Treg cells are particularly important for calming down effector T cells (or T-eff cells). These are several different types of T cell types that ‘actively’ respond to a stimulus. They include:

  • Helper T cells (TH cells) which assist other white blood cells in the immunological process
  • Killer T cells which destroy virus-infected cells, tumor cells, and are involve in transplant rejection.

The normal situation in the body is to have a balance between T-eff cells and Treg cells. If there are too many T-eff cells, there is increased chances of autoimmunity – or the immune system attacking healthy cells.

Microsoft Word - Tregs Review Final

A delicate balance between healthy and autoimmune disease. Source: Researchgate

Too many Treg cells is not a good situation either, however, as they would leave the immune system suppressed and individuals vulnerable to disease.

How are Treg cells involved with Parkinson’s disease?

So, in Parkinson’s disease, researchers believe that the build up of the Parkinson’s associated protein, alpha synuclein may be toxic and killing certain cells in the brain (such as the dopamine neurons). When the cell dies and the alpha synuclein is released into the surrounding environment of the brain, it most likely does two things:

  1. irritates and activates the resident immune cells, called microglia
  2. activates the wider immune system, resulting in T-cell infiltration of the brain

The T-cells snoop around, detect that something isn’t quite right and then release their own cytokines which further activates the microglia. The microglia then release pro-inflammatory toxic chemicals which indiscriminately damage the unhealthy and healthy cells in the local area.

nihms734237f1

A.) The normal situation in PD; B.) the situation after GM-CSF treatment. Source: NCBI

Now the hypothesis is that GM-CSF may be able mediate this degenerative cycle by stimulating the induction of Treg cells, which can calm the activated microglia down, return it to a resting state and the healthy surrounding neurons survive intact.

Is there any research evidence for this effect in models of Parkinson’s disease?

Yes there is.

The group in Nebraska have actually been working ‘pre-clinically’ on this idea for some time:

Reynolds

Title: Neuroprotective activities of CD4+CD25+ regulatory T cells in an animal model ofParkinson’s disease.
Authors: Reynolds AD, Banerjee R, Liu J, Gendelman HE, Mosley RL.
Journal: J Leukoc Biol. 2007 Nov;82(5):1083-94.
PMID: 17675560

In this study, the researchers demonstrated that by increasing the number of activated Treg cells in neurotoxin (MPTP)-injected mice, they could produce a greater than 90% level of protection of the dopamine neurons when compared to mice that did not receive the increase of Treg cells.

The Treg cells were found to mediate this neuroprotection through suppression of the microglial response to the neurotoxin. The investigators concluded that their data strongly supported the use of immunomodulation as a strategy for treating Parkinson’s.

They next extended these findings by looking at whether GM-CSF could provide neuroprotection in the same model of Parkinson’s disease:

Treg2

Title: GM-CSF induces neuroprotective and anti-inflammatory responses in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine intoxicated mice.
Authors: Kosloski LM, Kosmacek EA, Olson KE, Mosley RL, Gendelman HE.
Journal: J Neuroimmunol. 2013 Dec 15;265(1-2):1-10.
PMID: 24210793            (This article is OPEN ACCESS if you would like to read it)

In this study, the researchers gave GM-CSF prior to the neurotoxin (MPTP) which kills dopamine neurons. GM-CSF freely cross the blood-brain barrier which inhibits a lot of other drugs from entering the brain. This treatment protected the dopamine neurons and the investigators found increased Treg induction and reduced activation of the microglia cells.

This neuroprotective effect could also transferred between animals. Treg cells from GM-CSF treated mice were transferred to MPTP-treated mice and neuroprotection of the dopamine neurons was observed in those animals. The researchers concluded that the results provide evidence that GM-CSF modulation of the immune system could be of clinical benefit for people with Parkinson’s disease.

And they are not the only investigators who have demonstrated this. In addition to the work produced by the Nebraskan research team, other research groups have also observed beneficial effects of GM-CSF in models of Parkinson’s disease (Click here, here and here to read some of those reports).

In fact, for a very good OPEN ACCESS review on the topic of immunomodulation for Parkinson’s disease – click here.

And with all of this research backing them, the team in Nebraska decided to move GM-CSF towards the clinic with a small phase I clinical trial.

nebraska

The Nebraska team: Dr Howard Gendelman, Dr Pamela Santamaria & Prof R. Lee Mosley. Source: Omaha

What did they find in the clinical trial?

In their randomized, double-blind, phase 1 clinical trial of 20 people with Parkinson’s disease taking either sargramostim (10 subjects) or a placebo control solution (10 subjects) for 56 days, the researchers found that Sargramostim firstly increases the the induction of Treg cells, and mediated suppression of the immune cells

More importantly, the sargramostim treated group demonstrated a modest improvement in their motor performance scores after 6 and 8 weeks of treatment when compared with the placebo group. The study was not large enough in size or duration for robust conclusions to be made, but the deviation between the two groups in motor scores in intriguing. This is particularly curious given that the sargramostim treatment group returned to a similar level of performance as the control (placebo) group at the 8 week assessment when they were no longer on sargramostim:

Figure

Change in motor scores of the participants. Source: Nature

One of the interesting features of this study was that the participants were a mixed bunch with regards to their Parkinson’s disease. The participants ranged in age from 53 to 76 years (mean age of 64) and they had had symptoms for 3–14 years (the mean was 7 years). It would be interesting to know (in a larger study) if there is any difference in the effect of this treatment based on length of time since diagnosis.

Another interesting aspect of the study is that it was double-blind. It is rather rare for a phase I clinical study to be double-blind, as they are usually just testing safety and tolerance. But given that sargramostim is used in the clinic already, the investigators had more flexibility with the study design. The double blind nature of the results only makes the findings more intriguing though.

The next step in this research is to plan a larger clinical study in 1-2 years time. The delay is caused by the desire for that trial to focus on an oral tablet (currently Sargramostim is only administered via an injection – not a popular route!). Those follow up studies will require groups taking different doses of the drug to get a better idea of effective dosages.

So what does it all mean?

Artificial modulation of the immune system represents tremendous opportunities for not only Parkinson’s disease, but also other conditions such as Alzheimer’s disease and amyotrophic lateral sclerosis. Recently, some researchers have concluded a clinical study of immunomodulation for Parkinson’s disease after almost 20 years of preclinical experimentation. The results are very interesting and may provide us with a novel method of treating the condition.

We here at the SoPD will be interested to see if Sargramostim makes it through the clinical testing process alone (as a “mono-therapy”) for Parkinson’s disease, or whether it will be used in combination with other drugs. One potential issue for this approach is that it leaves the individual with a suppressed immune system to defend them against other infectious agents.

Having said that, the fact that this approach may work could also tell us a great deal about the nature of Parkinson’s disease itself, and raising the idea that the body’s immune response could be involved with the progression of this neurodegenerative condition. We already know from several studies that certain anti-inflammation drugs (particularly Ibuprofen) can help to lower the risk of developing Parkinson’s disease (Click here for more on Ibuprofen).

Perhaps while we wait for the pill version of Sargramostim, a separate Ibuprofen study could be conducted to determine if this drug could slow down the progression of the disease.


The banner for today’s post was sourced from Diamond

Shining a light on movement

10-years-of-optogenetics

Researchers are using a powerful new tool to determine which parts of the brain are involved in movement.

The technology involves shining light on brain cells…and well, a bit of biological magic.

Today we will review some newly published research highlighting how this approach and discuss what it means for Parkinson’s disease.


crop

The Vienna city hall. Source: EUtourists

Personal story: I was at the Dopamine 2016 conference in September last year in lovely Vienna (Austria). Wonderful city, beautiful weather, and an amazing collection of brilliant researchers focused on all things dopamine-related. The conference really highlighted all the new research being done on this chemical.

There was – of course – a lots of research being presented on Parkinson’s disease, given that dopamine plays such an important role in the condition.

And it was all really interesting.

Anyways, I was sitting in one of the lecture presentation session, listening to all these new results being discussed.

And then, a lady from Carnegie Mellon University stood up and (without exaggeration) completely – blew – my – mind!

Her name is Aryn H. Gittis:

gittis_hd

She is an Assistant Professor in the Department of Biological Sciences at Carnegie Mellon University, where her group investigates the neural circuits underlying the regulation of movement, learning,  motivation, and reward.

And the ‘mind blowing‘ research that she presented in Vienna has recently been published in the journal Nature Neuroscience:

Motor.jpg
Title: Cell-specific pallidal intervention induces long-lasting motor recovery in dopamine-depleted mice
Authors: Mastro KJ, Zitelli KT, Willard AM, Leblanc KH, Kravitz AV & Gittis AH
Journal: Nature Neuroscience (2017) doi:10.1038/nn.4559
PMID: 28481350

In this report, Dr Gittis and her colleagues demonstrated that elevating the activity of one type of cell in an area of the brain called the globus pallidus, could provide long lasting relief from Parkinson’s-like motor features.

Hang on a second. What is the globus pallidus?

The globus pallidus is a structure deep in the brain and before Dr Gittis and her colleagues published their research, we already knew it played an important role in our ability to move.

Movement is largely controlled by the activity in a specific group of brain regions, collectively known as the ‘Basal ganglia‘.

B9780702040627000115_f11-01-9780702040627

The basal ganglia structures (blue) in the human brain. Source: iKnowledge

But while the basal ganglia controls movement, it is not the starting point for the movement process.

The prefrontal cortex is where we do most of our ‘thinking’. It is the part of the brain that makes decisions with regards to many of our actions, particularly voluntary movement. It is involved in what we call ‘executive functions’. It is the green area in the image below.

motor areas

Areas of the cortex. Source: Rasmussenanders

Now the prefrontal cortex might come up with an idea: ‘the left hand should start to play the piano’. The prefrontal cortex will communicate this idea with the premotor cortex and together they will send a very excited signal down into the basal ganglia for it to be considered. Now in this scenario it might help to think of the cortex as hyperactive, completely out of control toddlers, and the basal ganglia as the parental figure. All of the toddlers are making demands/proposals and sending mixed messages, and it is for the inhibiting basal ganglia to gain control and decide which is the best.

So the basal ganglia receives signals from the cortex, processes that information before sending a signal on to another important participant in the regulation of movement: the thalamus.

Brain_chrischan_thalamus

A brain scan illustrating the location of the thalamus in the human brain. Source: Wikipedia

The thalamus is a structure deep inside the brain that acts like the central control unit of the brain. Everything coming into the brain from the spinal cord, passes through the thalamus. And everything leaving the brain, passes through the thalamus. It is aware of most everything that is going on and it plays an important role in the regulation of movement. If the cortex is the toddler and the basal ganglia is the parent, then the thalamus is the ultimate policeman.

Now to complicate things for you, the processing of movement in the basal ganglia involves a direct pathway and an indirect pathway. In the simplest terms, the direct pathway encourages movement, while the indirect pathway does the opposite: inhibits it.

screen_shot_2013-02-13_at_101403_pm1360822462546

Source: Studyblue

The thalamus will receive signals from the two pathways and then decide – based on those signals – whether to send an excitatory or inhibitory message to the primary motor cortex, telling it what to do (‘tell the muscles to play the piano’ or ‘don’t start playing the piano’, respectively). The primary motor cortex is the red stripe in the image below.

motor areas

The primary motor cortex then sends this structured order down the spinal cord (via the corticospinal pathway) and all going well the muscles will do as instructed.

 

4c3c1107f003a36da4ace0eec928dc5c

Source: adapted from Pinterest 

Now, in Parkinson’s disease, the motor features (slowness of movement and resting tremor) are associated with a breakdown in the processing of those direct and an indirect pathways. This breakdown results in a stronger signal coming from the indirect pathway – thus inhibiting/slowing movement. This situation results from the loss of dopamine in the brain.

Pathways

Excitatory signals (green) and inhibitory signals (red) in the basal ganglia, in both a normal brain and one with Parkinson’s disease. Source: Animal Physiology 3rd Edition

Under normal circumstances, dopamine neurons release dopamine in the basal ganglia that helps to mediate the local environment. It acts as a kind of lubricant for movement, the oil in the machine if you like. It helps to reduce the inhibitory bias of the basal ganglia.

Thus, with the loss of dopamine neurons in Parkinson’s disease, there is an increased amount of activity coming out of the indirect pathway.

And as a result, the thalamus is kept in an overly inhibited state. With the thalamus subdued, the signal to the motor cortex is unable to work properly. And this is the reason why people with Parkinson’s disease have trouble initiating movement.

F1.large

Source: BJP

Now, as you can see from the basic schematic above, the globus pallidus is one of the main conduits of information into the thalamus. Given this pivotal position in the regulation of movement, the globus pallidus has been a region of major research focus for a long time.

It is also one of the sites targeted in ‘deep brain stimulation’ therapy for Parkinson’s disease (the thalamus being another target). Deep brain stimulation (or DBS) involves placing electrodes deep into the brain to help regulate activity.

F1.large-1

DBS in the globus pallidus. Source: APS

By regulating the level of activity in the globus pallidus, DBS can control the signal being sent to the thalamus, reducing the level of inhibition, and thus alleviating the motor related features of the Parkinson’s disease.

The dramatic effects (and benefits) of deep brain stimulation can be seen in this video (kindly provided by fellow kiwi Andrew Johnson):

 

Deep brain stimulation is not perfect, however.

The placing of the electrodes can sometimes be off target, resulting in limited beneficial effects. Plus the tuning of the device can be a bit fiddly in some cases.

A more precise method of controlling the globus pallidus would be ideal.

Ok, so the globus Pallidus region of the brain is important for movement. What did Dr Gittis and her colleagues find in their research?

They used an amazing piece of technology called ‘optogenetics‘ to specifically determine which group of cells in the globus pallidus are involved in the inhibitory signals going to the thalamus.

And their results are VERY interesting.

But what is optogenetics?

Good question.

The short answer: ‘Magic’

The long answer:  In 1979, Nobel laureate Francis Crick suggested that one of the major challenge facing the study of the brain was the need to control one type of cell in the brain while leaving others unaltered.

130628164406-watson-crick-cambridge-story-top

The DNA duo: Francis Crick (left) and James Watson. Source: CNN

Electrical stimulation cannot address this challenge because electrodes stimulate everything in the immediate vicinity without distinction. In addition the signals from electrodes lack precision; they cannot turn on/off neurons as dynamically as we require. The same problems (and more) apply to the use of drugs.

Crick later speculated that the answer might be light.

How on earth would you do that?

Well, in 1971 – eight years before Crick considered the problem – two researchers, Walther Stoeckenius and Dieter Oesterhelt, discovered a protein, bacteriorhodopsin, which acts as an ion pump on the surface of a cell membrane. Amazingly, this protein can briefly become activated by green light.

A rather remarkable property.

Later, other groups found similar proteins. One such protein, called ‘Channelrhodopsin’, was discovered in green algae (click here to read more on this). When stimulated by particular frequencies of light, these channels open up on the cell surface and allow ions to pass through. If enough channels open, this process can stimulate particular activity in the cell.

500px-ChR2_cartoon_Wong_et_al

Channelrhodopsin. Source: Openoptogenetics

Interesting, but how do you get this into the brain?

This is Karl Diesseroff:

7663_h_10630611

Source: Ozy

Looks like the mad scientist type, right? Well, remember his name, because this guy is fast heading for a Nobel prize.

He’s awesome!

He is the D. H. Chen Professor of Bioengineering and of Psychiatry and Behavioral Sciences at Stanford University. And he is one of the leading researchers in a field that he basically started.

Back in 2005, he and his collaborators published this research report:

opto
Title: Millisecond-timescale, genetically targeted optical control of neural activity
Authors: Boyden ES, Zhang F, Bamberg E, Nagel G, Deisseroth K.
Journal: Nat Neurosci. 2005 Sep;8(9):1263-8. Epub 2005 Aug 14.
PMID: 16116447

In this research report, Deisseroth and his colleagues (particularly Ed Boyden, lead author and now a professor of Biological Engineering at the McGovern Institute for Brain Research at MIT) took the short section of DNA that provides the instructions for making Channelrhodopsin from green algae and they put that piece of DNA into neurons.

And when they then shined blue light on the neurons, guess what happened? Yes, the neurons became activated – that is to say, they produced an ‘action potential’, which is one of the way information is passed from one neuron to another.

Like I said ‘Magic’!

Optogenetic-infographic

Source: Sqonline

And the best part of this biological manipulation was that Deisseroth and his colleagues could activate the neurons with absolutely amazing precision! By pulsing light on the cells for just millisecond periods, they could elicit instant action potentials:

fncir-03-021-g005

Precise control of the firing of a neuron. Source: Frontiers

And of course any surrounding cells that do not have the Channelrhodopsin DNA were not affected by the light, but were activated by the signal coming from the Channelrhodopsin+ cells.

This original research report lead to a gold rush-like search for other proteins that are light activated, and we now have an ever increasing toolbox of new proteins with curious properties. For example, we can now not only turn on neurons, but we also have proteins that can shut their activity down, blocking any action potentials (with proteins called ‘Halorhodopsin’ – click here for more on this). And many of these proteins are activated by different frequencies of light. It is really remarkable biology.

Opto2

Source: Harvard

For an excellent first-hand history of the early development of optogenetics (written by Ed Boydon who worked with Diesseroff on the first optogenetics study) – click here.

Two years after the first report of optogenetics, the first research demonstrating the use of this technology in the brain of a live animal was published (Click here and here to read more on this). And these fantastic tools are not just being used in the brain, they are being applied to tissues all over the body (for example, optogenetics can be used to make heart cells beat – click here to read more on this).

This TED talk video of Ed Boyden’s description of optogenetics is worth watching if you want to better understand the technique and to learn more about it:

Ok, so Dr Gittis and her colleagues used optogenetics in their research. What did they find?

Well, from previous research they knew that there were two types of neurons in the globus pallidus that regulate a lot of the activity in this region. The two types were identifiable by two different proteins: Lim homeobox 6 (Lhx6) and Parvalbumin (PV).

The Lhx6 neurons, which do not have any PV protein, are generally concentrated in the medial portion of the globus pallidus (closer to the centre of the brain). These Lhx6 neurons also have strong connections with the striatum and substantia nigra parts of the brain. The PV neurons, on the other hand, are more concentrated in the lateral portions of the globus pallidus (closer to the side of the brain), and they have strong connections with the thalamus (Click here to read this previous research).

In their new research report, Dr Gittis and her colleagues have used optogenetics to determine the functions of these two types of cells in the globus pallidus.

Initially, they stimulated both Lhx6 and PV neurons at the same time to see if they could restore movement in mice that had been treated with a neurotoxin (6-OHDA) that killed all the dopamine neurons. Unfortunately, they saw no rescue of the motor abilities of the mice.

They next shifted their attention to activating the two groups of cells separately to see if one of them was inhibiting the other. And when they stimulated the PV neurons alone, something amazing happened: the mice basically got up and started moving.

But the really mind blowing part: even after they turned off the stimulating light – after the pulse of light stopped – the mice were still able to keep moving around.

And this effect lasted for several hours! (note that the red line – indicating a decrease in immobility – in the image below remains stable after the stimulation of light pulses – blue lines – has stopped. Even between light pulses the mouse doesn’t return to immobility).

nn.4559-F2

Stimulation of the PV neurons. Source: Nature

The investigators then tested the reverse experiment: inhibiting the Lhx6 neurons.

And guess what?

They found that by inhibiting the Lhx6 neurons with pulses of light, they could restore movement in the dopamine-depleted mice (and again for hours beyond stimulation – note the blue line in the image below remains even after the light pulses – green lines – have stopped).

nn.4559-F4

Inhibiting of the Lhx6 neurons. Source: Nature

This result blew my mind at the conference in Vienna. And even now as I write this, I am still….well, flabbergasted! (there’s a good word).

In addition to being a very elegant experiment and use of this new optogenetic technology, this study opens new doors for us in the Parkinson’s disease research field regarding our understanding of how movement works and how we can now potentially treat PD.

Is optogentics being tested in the clinic?

The incredible answer to this question is: Yes.

Retrosense-logo

Source: Retrosense

A company in Ann Arbor (Michigan) called RetroSense Therapeutics announced in March of 2016 that they had treated their first subject in a Phase I/IIa, open-label, dose-escalation clinical study of the safety and tolerability of their lead product, RST-001 in patients with retinitis pigmentosa (Click here for the press release).

Eyeball

Source: Michiganvca

Retinitis pigmentosa is an inherited eye disease that causes severe vision impairment due to the progressive degeneration of the rod photoreceptor cells in the retina. The condition starts with patients experiencing progressive “tunnel vision” and eventual leads to blindness.

RetroSense’s lead product, RST-001 is basically a virus that infects cells with the photosensitivity gene, channelrhodopsin-2, that we discussed above. Several studies have demonstrated the ability of this approach to restore the perception of light and even vision in experimental models of blindness (Click here to read more about this).

The therapy involves injecting RST-001 into the retinas of patients who are blind. The infected cells will then fire when stimulated with blue light coming into the eye, and this information will hopefully be passed on to the brain. All going well, RetroSense plans to enroll 15 blind subjects in its trial, and they will follow them for two years. They hope to release some preliminary data, however, later this year. And a lot of people will be watching this trial and waiting for the results.

So, yes, optogenetics is being tested in humans.

Obviously, however, these are the first tentative steps in this new field. And it may be sometime before the medical regulatory bodies allow researchers to start conducting optogentic trials in the brain, let alone on people with Parkinson’s disease.

What does it all mean?

It is always rather wondrous where new discoveries take us.

A little over 10 years ago, some scientists discovered that by inserting a photosensitivity gene into brain cells they could control the firing of those cells with rapid pulses of light. And now other researchers are using that technology not only to better understand the works of our brains and how we move, but also to help make blind people see again.

Whether this technology will be able to replace therapies like deep brain stimulation with a more precise method of controlling the firing of the globus pallidus, is yet yo be seen. But this amazing new technique in our research toolbox will most certainly help to enhance our understanding of Parkinson’s disease. Taking us one step closer to ridding ourselves of it entirely.


The banner for today’s post was sourced from Scientifica