Editorial: Putting 200 years into context

April 12, 2017April 12, 2017 ~ Simon ~ 4 Comments

200

Here at the SoPD we understand and are deeply sympathetic to the frustration felt by the Parkinson’s community regarding the idea of ‘200 years and still no cure’.

As research scientists, we are in the trench everyday – fighting the good fight – trying to find ways of alleviating this terrible condition. And some of us are also in the clinics, interacting with sufferers and their families, listening to their stories and trying to help. While we do not deal directly with the day-to-day trials of living with Parkinson’s disease, we are keenly aware of many of the issues and are fully invested in trying to correct this condition.

972px-Paralysis_agitans_(1907,_after_St._Leger)

Source: Wikipedia

We do feel, however, that it is important to put some context into that ‘200 years’ time point that we are observing this week. It is too easy for people to think “wow, 200 years and still no cure?”

In our previous post – made in collaboration with Prof Frank Church of the Journey with Parkinson’s blog – we listed the major historical milestones and discoveries made in the Parkinson’s disease field during the last 200 years.

The most striking feature of that time line, however, is how just little actually happened during the first 100 years.

In fact for most of that period, Parkinson’s disease wasn’t even called ‘Parkinson’s disease’.

Of the 48 events that we covered on that time line, 37 of them have occurred in the last 50 years (26 since 2000).

Taking this line of thought one step further, 2017 is also the 20 year anniversary of the discovery of alpha synuclein‘s association with Parkinson’s disease. And what a remarkable 20 years that has been. In 1997, a group of researcher at the National institute of Health led by Robert Nussbaum reported the first genetic mutation in the alpha synuclein gene that infers vulnerability to Parkinson’s disease.

Since then, we have:

identified multiple additional mutations within that same gene that increase the risk of developing Parkinson’s disease.
determined which forms of alpha synuclein are toxic.
identified alpha synuclein as an important component of Lewy bodies – the dense clusters of protein found in the Parkinsonian brain.
discovered numerous methods by which alpha synuclein can be passed between cells – potentially aiding in the spread of Parkinson’s disease.
developed and validated models of Parkinson’s disease based on manipulations of alpha synuclein (including numerous genetically engineered mice, viral over-expression models, etc).
identified alpha synuclein in the lining of the gut of people with Parkinson’s disease and this has aided us in developing new theories as to how the condition may start.
set up and run numerous clinical trials targeting alpha synuclein (and we eagerly await the results of those trials).
published over 6200 scientific papers (don’t believe me? Click here) – that’s over 300 publications per year!

Alpha synuclein protein. Source: Wikipedia

And the truly amazing part? All of these particular achievements are only dealing with just the one gene: alpha synuclein.

Since the identification of the alpha synuclein mutations, we have subsequently discovered genetic mutations in over 20 other genes that increase the risk of developing Parkinson’s disease. And we have conducted the same activities/experiments for most of those genes as we have for alpha synuclein.

For example, in 2004 we discovered that people with genetic mutations in a gene called glucocerebrosidase (or GBA) had an increased risk of developing Parkinson’s disease. In 2016, just 12 years after that discovery we have started a clinical trial designed specifically for those people (Click here for more on this).

wwwnew2_0

Source: Parkinson’s UK

We here at the SoPD are fully supportive of campaigns like #WeWontWait, and this post was not written (nor meant to be taken) as an excuse response to the ‘200 years and no cure’ frustration. I can understand how it may be read that way, but I did not know how else to write it. And I thought it needed to be written.

The point of this entire post is that those 200 years need to be put into context.

And while all of these words aren’t going to make life easier for someone living with Parkinson’s to deal with their situation, in addition to raising awareness this week I think it is important for the Parkinson’s community to also understand just how far we have come, and how fast we are currently progressing.

The question can be asked: will this be the last major anniversary we acknowledge with regards to Parkinson’s disease?

I sincerely think that there is cause to hope that it is.

Let me finish with a personal note:

I have a good friend – let’s call him Matt.

As a young boy, Matt remembers his grandfather having Parkinson’s disease. He remembers growing up watching the trials and tribulations that the old man went through with the condition. There were basically no treatment options when Matt’s grandfather was diagnosed and little in the way of support for the family. His grandfather’s body simply froze up as the disease progressed. L-dopa probably only became available to Matt’s grandfather during the latter stages of the disease.

Four years ago Matt’s father was diagnosed with Parkinson’s disease.

Thanks to scientific advances, however, Matt’s dad now has a wide range of treatment options on the medication side of things. The disease can be managed so that he can still play his golf and enjoy his retirement – in a way that his own father never could. He also has numerous surgical options once those medications lose their effectiveness (eg. deep brain stimulation, Pallidotomy, etc). The chances are very likely that Matt’s father will pass on by natural causes before he requires many of those additional options.

This is the progress that we have made.

But there is still a lot of work to be done of course.

During a lunch shortly after his father’s diagnosis, Matt looked squarely across the table at me. Me, the Parkinson’s researcher. All of the usual jovial nature was missing from his face and he simply muttered the words ‘hurry up’.

Whether he was speaking for his father, himself or his own young kids, I understood where his words were coming from and the sentiment.

And, as this post and the previous post point out, we are hurrying up.

The banner for today’s post was sourced from BMO

Milestones in Parkinson’s disease research and discovery

April 11, 2017April 12, 2017 ~ Simon ~ 4 Comments

Self-Reflected-in-violets

For today’s post, we have teamed up with Prof Frank Church from the Journey with Parkinson’s blog to bring readers an ‘Introduction to the historical timeline on Parkinson’s disease’.

The idea for this project started as a conversation between Frank and his partner Barbara during a recent weekend at the beach in North Carolina.

Frank said: “Wouldn’t it be cool to publish a Parkinson’s historical timeline for Parkinson’s awareness month?”

However, to complete this project Frank felt it necessary to bring in some extra help in the form of a Parkinson’s expert.

And when everyone else said they were too busy, Frank contacted us.

Truly flattered, we immediately said yes. And the rest is history.

We are happy to present the milestones in Parkinson’s disease research and discover, though we do apologise to the clinicians, scientists, health-care specialists, and their projects that were not cited here but we limited the timeline to ~50 notations.

Below there are six panels outlining different stages of the history of Parkinson’s disease, and under each of them we have briefly described each of the events in the panel.

We hope you like it.

1817-1919- Milestones in Parkinson’s Disease Research and Discovery (Part 1a: Historical):

First description of Parkinson’s disease

In 1811, Mr James Parkinson of no. 1 Hoxton Square (London) published a 66 page booklet called an ‘An Essay on the Shaking Palsy’. At the date of printing, it sold for 3 shillings (approx. £9 or US$12). The booklet was the first complete description of a condition that James called ‘Paralysis agitans’ or shaking palsy. In his booklet, he discusses the history of tremor and distinguishes this new condition from other diseases. He then describes three of his own patients and three people who he saw in the street.

The naming of Parkinson’s disease

Widely considered the ‘Father of modern neurology’, the importance of Jean-Martin Charcot’s contribution to modern medicine is rarely in doubt. From Sigmund Freud to William James (one of the founding fathers of Psychology), Charcot taught many of the great names in the early field of neurology. Between 1868 and 1881, Charcot focused much of his attention on the ‘paralysis agitans’. Charcot rejected the label ‘Paralysis agitans’, however, suggesting that it was misleading in that patients were not markedly weak and do not necessarily have tremor. Rather than Paralysis Agitans, Charcot suggested that Maladie de Parkinson (or Parkinson’s disease) would be a more appropriate name, bestowing credit to the man who first described the condition. And thus 70 years after passing away, James Parkinson was immortalized with the disease named after him.

The further clinical characterisation of Parkinson’s disease

British neurologist Sir William Gowers published a two-volume text called the Manual of Diseases of the Nervous System (1886, 1888). In this book he described his personal experience with 80 people with Parkinson’s disease in the 1880s. He also identified the subtle male predominance of the disorder and provided illustrations of the characteristic posture. In his treatment of Parkinson’s tremor, Gower used hyoscyamine, hemlock, and hemp (cannabis) as effective agents for temporary tremor abatement.

The discovery of the chemical dopamine

In the Parkinsonian brain there is a severe reduction in the chemical dopamine. This chemical was first synthesised in 1910 by George Barger and James Ewens at the Wellcome labs in London, England.

The discovery of Lewy bodies

One of the cardinal features of Parkinson’s disease in the brain is the presence of Lewy bodies – circular clusters of protein. In 1912, German neurologist Friedrich Lewy, just two years out of medical school and still in his first year as Director of the Neuropsychiatric Laboratory at the University of Breslau (now Wroclaw, Poland) Medical School discovered these ‘spherical inclusions’ in the brains of a people who had died with Parkinson’s disease.

The importance of the substantia nigra in Parkinson’s disease

The first brain structure to be associated with Parkinson’s disease was the substantia nigra. This region lies in an area called the midbrain and contains the majority of the dopamine neurons in the human brain. It was in 1919 that a Russian graduate student working in Paris, named Konstantin Tretiakoff, first demonstrated that the substantia nigra was associated with Parkinson’s disease. Tretiakoff also noticed circular clusters in the brains he examined and named them ‘corps de Lewy’ (or Lewy bodies) after the German neurologist Friedrich Lewy who first discovered them.

1953-1968- Milestones in Parkinson’s Disease Research and Discovery (Part 1b: Historical):

The first complete pathologic analysis of the Parkinsonian brain

The most complete pathologic analysis of Parkinson’s disease with a description of the main sites of damage was performed in 1953 by Joseph Godwin Greenfield and Frances Bosanquet.

The discovery of a functional role for dopamine in the brain

Until the late 1950s, the chemical dopamine was widely considered an intermediate in the production of another chemical called norepinephrine. That is to say, it had no function and was simply an ingredient in the recipe for norepinephrine. Then in 1958, Swedish scientist Arvid Carlsson discovered that dopamine acts as a neurotransmitter – a discovery that won Carlsson the 2000 Nobel prize for Physiology or Medicine.

The founding of the Parkinson’s Disease Foundation

In 1957, a nonprofit organisation called the Parkinson’s Disease Foundation was founded by William Black. It was committed to finding a cure for Parkinson’s Disease. Since its founding in 1957, PDF has funded more than $115 million worth of scientific research in Parkinson’s disease.

The discovery of the loss of dopamine in the brain of people with Parkinson’s disease

In 1960, Herbert Ehringer and Oleh Hornykiewicz demonstrated that the chemical dopamine was severely reduced in brains of people who had died with Parkinson’s disease.

The first clinical trials of Levodopa

Knowing that dopamine can not enter the brain and armed with the knowledge that the chemical L-dopa was the natural ingredient in the production of dopamine, Oleh Hornykiewicz & Walther Birkmayer began injecting people with Parkinson’s disease with L-dopa in 1961. The short term response to the drug was dramatic: “Bed-ridden patients who were unable to sit up, patients who could not stand up when seated, and patients who when standing could not start walking performed all these activities with ease after L-dopa. They walked around with normal associated movements and they could even run and jump.” (Birkmayer and Hornykiewicz 1961).

The first internationally-used rating system for Parkinson’s disease

In 1967, Melvin Yahr and Margaret Hoehn published a rating system for Parkinson’s disease in the journal Neurology. It involves 5 stages, ranging from unilateral symptoms but no functional disability (stage 1) to confinement to wheel chair (stage 5). Since then, a modified Hoehn and Yahr scale has been proposed with the addition of stages 1.5 and 2.5 in order to help better describe the intermediate periods of the disease.

Perfecting the use of L-dopa as a treatment for Parkinson’s disease

In 1968, Greek-American scientist George Cotzias reported dramatic effects on people with Parkinson’s disease using oral L-dopa. The results were published in the New England Journal of Medicine. and L-dopa becomes a therapeutic reality with the Food and Drug Administration (FDA) approving the drug for use in Parkinson’s disease in 1970. Cotzias and his colleagues were also the first to describe L-dopa–induced dyskinesias.

1972-1997- Milestones in Parkinson’s Disease Research and Discovery (Part 1c: Historical):

Levodopa + AADC inhibitors (carbidopa or benserazide)

When given alone levodopa is broken down to dopamine in the bloodstream, which leads to some detrimental side effects. By including an aromatic amino acid decarboxylase (AADC) inhibitor with levodopa allows the levodopa to get to the blood-brain barrier in greater amounts for better utilisation by the neurons. In the U.S., the AADC inhibitor of choice is carbidopa and in other countries it’s benserazide.

The discovery of dopamine agonists

Dopamine agonists are ‘mimics’ of dopamine that pass through the blood brain barrier to interact with target dopamine receptors. Since the mid-1970’s, dopamine agonists are often the first medication given most people to treat their Parkinson’s; furthermore, they can be used in conjunction with levodopa/carbidopa. The most commonly prescribed dopamine agonists in the U.S. are Ropinirole (Requip®), Pramipexole (Mirapex®), and Rotigotine (Neupro® patch). There are some challenging side effects of dopamine agonists including compulsive behaviour (e.g., gambling and hypersexuality), orthostatic hypotension, and hallucination.

The clinical use of MAO-B inhibitors

In the late-1970’s, monoamine oxidase-B (MAO-B) inhibitors were created to block an enzyme in the brain that breaks down levodopa. MAO-B inhibitors have a modest effect in suppressing the symptoms of Parkinson’s. Thus, one of the functions of MAO-B inhibitors is to prolong the half-life of levodopa to facilitate its use in the brain. Very recently in clinical trials, it’s been shown that MAO-B inhibitors have some neuroprotective effect when used long-term. The most widely used MAO-B inhibitors in the U.S. include Rasagiline (Azilect) and Selegiline (Eldepryl and Zelpar); MAO-B inhibitors may reduce “off” time and extend “on” time of levodopa.

Fetal Cell transplantation

After successful preclinical experiments in rodents, a team of researchers in Sweden, led by Anders Bjorklund and Olle Lindvall, began the first clinical trials of fetal cell transplantation for Parkinson’s disease. These studies involved taking embryonic dopamine cells and injecting them into the brains of people with Parkinson’s disease. The cells then matured and replaced the cells that had been lost during the progression of the disease.

The discovery of MPTP

In July of 1982, Dr. J. William Langston of the Santa Clara Valley Medical Center in San Jose (California) was confronted with a group of heroin addicts who were completely immobile. A quick investigation demonstrated that the ‘frozen addicts’ had injected themselves with a synthetic heroin that had not been prepared correctly. The heroin contained a chemical called MPTP, which when injected into the body rapidly kills dopamine cells. This discovery provided the research community with a new tool for modelling Parkinson’s disease.

1997-2006- Milestones in Parkinson’s Disease Research and Discovery (Part 1d: Historical):

Alpha synuclein becomes the first gene associated with familial cases of Parkinson’s disease and its protein is found in Lewy bodies

In 1997, a group of researchers at the National institute of Health led by Robert Nussbaum reported the first genetic aberration linked to Parkinson’s disease. They had analysed DNA from a large Italian family and some Greek familial cases of Parkinson’s disease, and they

The gene Parkin becomes the first gene associated with juvenile Parkinson’s disease

The gene Parkin provides the instructions for producing a protein that is involved with removing rubbish from within a cell. In 1998, a group of Japanese scientists identified mutations in this gene that resulted in affected individuals being vulnerable to developing a very young onset (juvenile) version of Parkinson’s disease.

The first use of PET scan brain imaging for Parkinson’s disease

Using the injection of a small amount of radioactive material (known as a tracer), the level of dopamine present in an area of the brain called the striatum could be determined in a live human being. Given that amount of dopamine in the striatum decreases over time in Parkinson’s disease, this method of brain scanning represented a useful diagnostic aid and method of potentially tracking the condition.

The launch of Michael J Fox Foundation

In 1991, actor Michael J Fox was diagnosed with young-onset Parkinson’s disease at 29 years of age. Upon disclosing his condition in 1998, he committed himself to the campaign for increased Parkinson’s research. Founded on the 31^st October, 2000, the Michael J Fox Foundation has funded more than $700 million in Parkinson’s disease research, representing one of the largest non-governmental sources of funding for Parkinson’s disease.

The Braak Staging of Parkinson’s pathology

In 2003, German neuroanatomist Heiko Braak and colleagues presented a new theory of how Parkinson’s disease spreads based on the postmortem analysis of hundreds of brains from people who had died with Parkinson’s disease. Braak proposed a 6 stage theory, involving the disease spreading from the brain stem (at the top of the spinal cord) up into the brain and finally into the cortex.

The gene DJ1 is linked to early onset PD

DJ1 (also known as PARK7) is a protein that inhibits the aggregation of Parkinson’s disease-associated protein alpha synuclein. In 2003, researchers discovered mutations in the DJ1 gene that made people vulnerable to a early-onset form of Parkinson’s disease.

The first GDNF clinical trial indicates neuroprotection in people with Parkinson’s disease

A small open-label clinical study involving the direct delivery of the chemical Glial cell-derived neurotrophic factor (GDNF) into the brains of people with Parkinson’s disease indicated that neuroprotection. The subjects involved in the study exhibited positive responses to the treatment and postmortem analysis of one subjects brain indicated improvements in the brain.

The genes Pink1 and LRRK2 are associated with early onset PD

Early onset Parkinson’s is defined by age of onset between 20 and 40 years of age, and it accounts for <10% of all patients with Parkinson’s. Genetic studies are finding a causal association for Parkinson’s with five genes: alpha synuclein (SNCA), parkin (PARK2), PTEN-induced putative kinase 1 (PINK1), DJ-1 (PARK7), and Leucine-rich repeat kinase 2 (LRRK2). However it happens, and at whatever age it occurs, there is no doubt that genetics and environment combine together to contribute to the development of Parkinson’s.

The discovery of induced pluripotent stem (IPS) cells

In 2006, Japanese researchers demonstrated that it was possible to take skin cells and genetically reverse engineer them into a more primitive state – similar to that of a stem cell. This amazing achievement involved a fully mature cell being taken back to a more immature state, allowing it to be subsequently differentiated into any type of cell. This research resulted in the discoverer, Shinya Yamanaka being awarded the 2012 Nobel prize for Physiology or Medicine.

2007-2016- Milestones in Parkinson’s Disease Research and Discovery (Part 1e: Historical):

The introduction of the MDS-UPDRS revised rating scale

The Movement Disorder Society (MDS) unified Parkinson’s disease rating scale (UPDRS) was introduced in 2007 to address two limitations of the previous scaling system, namely a lack of consistency among subscales and the low emphasis on the non-motor features. It is now the most commonly used scale in the clinical study of Parkinson’s disease.

The discovery of Lewy bodies in transplanted dopamine cells

Postmortem analysis of the brains of people with Parkinson’s disease who had fetal cell transplantation surgery in the 1980-1990s demonstrated that Lewy bodies are present in the transplanted dopamine cells. This discovery (made by three independent research groups) suggests that Parkinson’s disease can spread from unhealthy cells to healthy cells. This finding indicates a ‘prion-like’ spread of the condition.

SNCA, MAPT and LRRK2 are risk genes for idiopathic Parkinson’s disease

Our understanding of the genetics of Parkinson’s is rapidly expanding. There is recent evidence of multiple genes linked to an increase the risk of idiopathic Parkinson’s. Interestingly, microtubule-associated protein tau (MAPT) is involved in microtubule assembly and stabilization, and it can complex with alpha synuclein (SNCA). Future therapies are focusing on the reduction and clearance of alpha synuclein and inhibition of Lrrk2 kinase activity.

IPS derived dopamine neurons from people with Parkinson’s disease

The ability to generate dopamine cells from skin cells derived from a person with Parkinson’s disease represents not only a tremendous research tool, but also opens the door to more personalized treatments of suffers. Induced pluripotent stem (IPS) cells have opened new doors for researchers and now that we can generate dopamine cells from people with Parkinson’s disease exciting opportunities are suddenly possible.

Neuroprotective effect of exercise in rodent Parkinson’s disease models

Exercise has been shown to be both neuroprotective and neurorestorative in animal models of Parkinson’s. Exercise promotes an anti-inflammatory microenvironment in the mouse/rat brain (this is but one example of the physiological influence of exercise in the brain), which helps to reduce dopaminergic cell death. Taking note of these extensive and convincing model system results, many human studies studying exercise in Parkinson’s are now also finding positive benefits from strenuous and regular exercise to better manage the complications of Parkinson’s.

Transeuro cell transplantation trial begins

In 2010, a European research consortium began a clinical study with the principal objective of developing an efficient and safe treatment methodology fetal cell transplantation in people with Parkinson’s disease. The trial is ongoing and the subjects will be followed up long term to determine if the transplantation can slow or reverse the features of Parkinson’s disease.

Successful preclinical testing of dopamine neurons from embryonic stem cells

Scientists in Sweden and New York have successfully generated dopamine neurons from human embryonic stem cells that can be successfully transplanted into animal models of Parkinson’s disease. Not only do the cells survive, but they also correct the motor deficits that the animals exhibit. Efforts are now being made to begin clinical trials in 2018.

Microbiome of the gut influences Parkinson’s disease

Several research groups have found the Parkinson’s disease-associated protein alpha synuclein in the lining of the gut, suggesting that the intestinal system may be one of the starting points for Parkinson’s disease. In 2016, researchers found that the bacteria in the stomachs of people with Parkinson’s disease is different to normal healthy individuals. In addition, experiments in mice indicated that the bacteria in the gut can influence the healthy of the brain, providing further evidence supporting a role for the gut in the development of Parkinson’s disease.

2016-2017- Milestones in Parkinson’s Disease Research and Discovery (Part 2: Clinical trials either recently completed or in progress)

Safety, Tolerability and Efficacy Assessment of Dynacirc (Isradipine) for PD (STEADY-PD) III trial

Isradipine is a calcium-channel blocker approved for treating high blood pressure; however, Isradipine is not approved for treating Parkinson’s. In animal models, Isradipine has been shown to slow the progression of PD by protecting dopaminergic neurons. This study is enrolling newly diagnosed PD patients not yet in need of symptomatic therapy. Participants will be randomly assigned Isradipine or given a placebo.

Treatment of Parkinson’s Psychosis with Nuplazid

Approximately 50% of the people with Parkinson’s develop psychotic tendencies. Treatment of their psychosis can be relatively difficult. However, a new drug named Nuplazid was recently approved by the FDA specifically designed to treat Parkinson’s psychosis.

Opicapone (COMT Inhibitor) as Adjunct to Levodopa Therapy in Patients With Parkinson Disease and Motor Fluctuations

Catechol-O-methyl transferase (COMT) inhibitors prolong the effect of levodopa by blocking its metabolism. COMT inhibitors are used primarily to help with the problem of the ‘wearing-off’ phenomenon associated with levodopa. Opicapone is a novel, once-daily, potent third-generation COMT inhibitor. It appears to be safer than existing COMT drugs. If approved by the FDA, Opicapone is planned for use in patients with Parkinson’s taking with levodopa who experience wearing-off issues.

Nilotinib (Tasigna® by Novartis) indicates positive results in phase I trial.

Nilotinib is a drug used in the treatment of leukemia. In 2015, it demonstrated beneficial effects in a small phase I clinical trial of Parkinson’s disease. Researchers believe that the drug activates the disposal system of cells, thereby helping to make cells healthier. A phase II trial of this drug to determine how effective it is in Parkinson’s disease is now underway.

ISCO cell transplantation trial begins

International Stem Cell Corporation is currently conducting a phase I clinical cell transplantation trial at a hospital in Melbourne, Australia. The company is transplanting human parthenogenetic stem cells-derived neural stem cells into the brains of people with Parkinson’s disease. The participants will be assessed over 12 months to determine whether the cells are safe for use in humans.

Neuropore’s alpha-synuclein stabilizer (NPT200-11) passes phase I trial

Neuropore Therapies is a biotech company testing a compound (NPT200-11) that inhibits and stablises the activity of the Parkinson’s disease-associated protein alpha synuclein. This alpha-synuclein inhibitor has been shown to be safe and well tolerated in humans in a phase I clinical trial and the company is now developing a phase II trial.

mGluR4 PAM (PXT002331) well tolerated in phase I trial

Prexton Therapeutics recently announced positive phase I clinical trial results for their lead drug, PXT002331, which is the first drug of its kind to be tested in Parkinson’s disease. PXT002331 is a mGluR4 PAM – this is a class of drug that reduces the level of inhibition in the brain. In Parkinson’s disease there is an increase in inhibition in the brain, resulting in difficulties with initiating movements. Phase II clinical trials to determine efficacy are now underway.

Initial results of Bristol GDNF trial indicate no effect

Following remarkable results in a small phase I clinical study, the recent history of the neuroprotective chemical GDNF has been less than stellar. A subsequent phase II trial demonstrated no difference between GDNF and a placebo control, and now a second phase II trial in the UK city of Bristol has reported initial results also indicating no effect. Given the initial excitement that surrounded GDNF, this result has been difficult to digest. Additional drugs that behave in a similar fashion to GDNF are now being tested in the clinic.

Immunotherapies proves safe in phase I trials (AFFiRis & Prothena)

Immunotherapy is a treatment approach which strengthens the body’s own immune system. Several companies (particularly ‘AFFiRis’ in Austria and ‘Prothena’ in the USA) are now conducting clinical trials using treatments that encourage the immune system to target the Parkinson’s disease-associated protein alpha synuclein. Both companies have reported positive phase I results indicating the treatments are well tolerable in humans, and phase II trials are now underway.

Living Cell Technologies Limited continue Phase II trial of NTCELL

A New Zealand company called Living Cell Technologies Limited have been given permission to continue their phase II clincial trial of their product NTCELL, which is a tiny capsule that contains cells which release supportive nutrients when implanted in the brain. The implanted participants will be blindly assessed for 26 weeks, and if the study is successful, the company will “apply for provisional consent to treat paying patients in New Zealand…in 2017”.

MAO-B inhibitors shown to be neuroprotective.

MAO-B inhibitors block/slow the break down of the chemical dopamine. Their use in Parkinson’s disease allows for more dopamine to be present in the brain. Recently, several longitudinal studies have indicated that this class of drugs may also be having a neuroprotective effect.

Inhalable form of L-dopa

Many people with Parkinson’s disease have issues with swallowing. This makes taking their medication in pill form problematic. Luckily, a new inhalable form of L-dopa will shortly become available following recent positive Phase III clinical trial results, which demonstrated a statistically significant improvements in motor function for people with Parkinson’s disease during OFF periods.

Exenatide trial results expected

Exenatide is a drug that is used in the treatment of diabetes. It has also demonstrated beneficial effects in preclinical models of Parkinson’s disease, as well as an open-label clinical study over a 14 month period. Interestingly, in a two year follow-up study of that clinical trial – conducted 12 months after the patients stopped receiving Exenatide – the researchers found that patients previously exposed to Exenatide demonstrated significant improvements compared to how they were at the start of the study. There is currently a placebo-controlled, double blind phase II clinical trial being conducted and the results should be reported before the end of 2017.

A personal reflection

As I suggested at the start of this post, this endeavour was entirely Frank’s idea – full credit belongs with him. I was more than happy to help him out with it though as I thought it was a very worthy project. During this 200 year anniversary, I believe it is very important to acknowledge just how far we have come in our understanding of Parkinson’s disease since James first put pen to paper and described the six cases he had seen in London.

And Frank’s idea perfectly captures this.

The banner for today’s post was sourced from Greg Dunn (we are big fans!)

James: The man behind the disease (Part 1)

April 1, 2017April 6, 2017 ~ Simon ~ 7 Comments

As part of Parkinson’s awareness month, and in observation of the 200 year anniversary of the first description of Parkinson’s disease, today we begin a four part set of posts looking at the man who made that first observation: James Parkinson.

Each week we will present various aspects about the man and his life.

Much of the material presented here has been replicated from our sister site Searching 4 James – a (much neglected) website celebrating the man and documenting the search for his likeness. To date, no portrait or image of the man has ever been found.

Source: Wellcome Images.

In her excellent book “James Parkinson, 1755-1824: From Apothecary to General Practitioner“, Shirley Roberts wrote that other sources have proposed that the man standing in the middle of the image above, talking to the villagers, is James Parkinson. The image appeared in James’ book ‘The Villager’s friend and physician’ (published in 1800), but (and I think you’ll agree) it does not give us much to work with.

Unfortunately Shirley Roberts made no reference to the sources of the proposal, but it is as close as we get to a likeness of the man, as he died before the first photographs were taken and there is no recorded painting of him.

Most people think of James Parkinson as a medical practitioner given his association with the disease that bears his name. But this singular association doesn’t really do the man credit. His contributions to medicine went well beyond the first description of ‘Parkinson’s disease’ – for example, James also gave the western world our first description of gout – a form of inflammatory arthritis that he and his father both suffered.

In addition, James was a ‘rockstar’ to the geological community, producing one of the most well regarded series of textbooks on the subject at the time. He was a political radical who wrote many pamphlets under the pseudonym “Old Hubert” and his associations with other radicals almost got him ‘transported’ (shipped out to the colonies). He was also a social reformist, calling for parliamentary reforms and universal suffrage. And his religious devotion made him a prominent figure within his church.

In short, he was a very interesting chap, who lived in (and had an impact on) interesting times.

THE WORLD OF JAMES

Before discussing the man himself, we must consider the world that James Parkinson was born into and the era he lived through. It provides us with the context within which we can fully appreciate the contributions that he made (including those beyond medicine).

James Parkinson was born on the 11th April 1755.

In the grand scale of things, the mid 1700’s was the peak of the little ice age, the middle of the age of enlightenment, and (critically) the start of the industrial revolution. The world was:

Pre USA (1776)
Pre French Revolution (1789)
Pre public electricity supply (1881)
Pre Napoleon (1769)
Pre Darwin (1809)

In London, King George II was on the English throne (soon to be replaced by George III), and Westminster bridge had just been finished (1750). The population of the city was approx. 700,000, but most of them lived in terrible conditions.

seutter_1750_london_view

A view of London (1750). Source: Historic Cities

James was born into a world where 74% of children born in London failed to reach the age of five. The medical world still practised humoral medicine (black bile, yellow bile, phlegm, and blood). Diseases were believed to be caused by an accumulation of “poisons” in the body, cured by bleeding, enemas, and sweating or blistering. The medical profession was:

Pre Ed Jenner’s vaccine for smallpox (1796)
Pre Rene Laennec’s stethoscope (1816)
Pre nitrous oxide (1800) or ether anaesthesia (1846)
Pre germ theory (Ignaz Semmelweis, 1847)
Pre Joseph Lister’s anti-septic surgery (1863).

Amputations were by far the most frequent surgeries, but the survival rate of the procedure was only 40% (and remember, there was no anaesthesia).

James Parkinson was born at no. 1 Hoxton Square in the liberty of Hoxton in Shoreditch, Middlesex. He would live all but the last 2 years of his life at that address.

In 1755, Hoxton was simply a scattering of houses, orchards and market gardens that lay approximately half a mile from one of the north-east gates of the walls of London. During the 17-1800s, Hoxton Square was considered a very fashionable area and young James would have grown up surrounded by open, reasonably well to do areas.

The maps below were made shortly before James was born, and it suggests open spaces, gardens, orchards and fields surrounding Hoxton.

London in 1746 (Shoreditch is indicated by the black square)
Source: John Roque’s Map

A map of Hoxton in 1746 – no 1. Hoxton Square (red arrow)
and St Leonard Church (blue arrow) are indicated.

James was born at the onset of the industrial revolution and with London prospering there was an enormous increase in the number of inhabitants. As more and more of London’s real estate became dedicated to business purposes, the inhabitants began spilling out into the surrounding areas. With transportation still limited to foot and horse, the people who worked in London needed to stay close to their place of employment, thus areas like Hoxton began to fill up rapidly. In 1788, there were 34,700 people living in Hoxton (in 5730 houses), which grew to 109,200 people in 1851 (in 15,433 houses).

Thus, during James’ life, Hoxton went through a radical transition. The large homes, orchards and gardens of his youth gave way to factories and over-crowding. And as a result, the ‘Parkinson and Son’ practise that he ran with his father (and later his own son) changed from serving a middle class clientele to dealing predominantly with the working class. With the prosperity of the time, there came a new trend of philanthropy, giving rise to the building of hospitals and mental asylums (‘madhouses’). James was the medical attendant for one of these madhouses, Holly House (Hoxton road, Hoxton).

The maps below were made in 1830 (shortly after James died – 1824) and indicate tremendous growth and expansion in London and the Hoxton area with the loss of much of the open spaces.

GREENWOOD MAP OF LONDON 1830 – Hoxton is indicated by the black square;
Tower of London (black arrow) and Westminster Abbey (red arrow) are also labelled – source: here

A map of Hoxton in 1830 – no 1. Hoxton Square (red arrow), St Leonard Church (blue arrow) and Holly House (Magenta arrow) are indicated.

THE FORMATIVE YEARS

James was baptised on the 29th of April 1755 in St Leonard’s church (Shoreditch) – the same church where he attended weekly services, got married, baptised his own children (and married some of them), and where he was eventually buried. The details of the baptism are recorded in the parish register, and read simply: James son of John and Mary Parkinson. Hoxton Square, Born 11th. Baptised 29th inst.

St Leonard’s church (1827) – Source

St Leonard’s church formed one of the key pillars of James’ life, and he could readily view the spire of the church one just block away from no.1 Hoxton Square.

The Parkinson family never owned the house at no. 1 Hoxton Square, which was owned by one Joshua Jenning. The building they lived in is gone now, but it was still standing in 1910 when Prof Leonard George Rowntree, a lecturer at Johns Hopkins Medical School (Baltimore), visited it and described it as:

“The house is a plain old three story building facing the east, on the northwest corner of Hoxton Square. Behind the main building and connected with it is a smaller two-story one with a central door opening into the little side street. This apparently was Parkinson’s office. Behind this again is another smaller building which may have served as a laboratory, as a library, or perhaps as a museum. Leading up to the deeply set, black, massive looking front door are a stone walk and deeply worn stone steps. The house is only a few feet back from the street and before it stands an old iron fence.

Uninteresting though the exterior is, upon entering this building one is impressed at the large size of the rooms and with the evidences of the prosperity of other days. We see in almost every room great carved open fire-places of elaborate design, and between some rooms large connecting arches. The deep panelling of walls and ceiling which was formerly so much in vogue is well preserved in some of the rooms on the second floor. One is surprised to find such an interesting interior behind such an uninviting exterior”

(Rowntree, 1912)

An image of no.1 Hoxton Square – Source

James was the eldest surviving child of John (an apothecary and surgeon) and Mary Parkinson. James had two sisters who survived to adulthood, Margaret Townley Parkinson (born 3rd August,1759) and Mary Sedgewood (born 11th January, 1763).

Little is known about the formative years of James Parkinsons. From his own writings, we know that he had a solid education in Latin and Greek as well as chemistry, biology and mathematics. James was fortunate to grow up in a ‘comfortable, cultured home’ with ‘a medical atmosphere’. But a thriving literary, scientific, and religious atmosphere also existed in Hoxton square. No fewer than fifteen residents of the Square are biographized in the Dictionary of National Biography – a distinction not shared by any other London Square from that time. Nothing is known about where James received his education. His name does not appear on the registry of scholars of the well known public schools of London, such as St Paul’s, the charterhouse, Christ’s Hospital, Merchants Taylors – all of which were within walking distance of Hoxton Square. Private home schooling was very popular during this time. James certainly did not attend Cambridge or Oxford University.

At age 16, James began his training to be an apothecary. In accordance with an antiquated Elizabethan Act of Parliament, in order to become a surgeon a young man had to serve an apprenticeship of seven years. James was apprenticed to his father, but 20 years later he wrote that “no apprenticeship should be advisable except to a hospital”. James was extremely critical of the traditional methods used in the teaching of medicine at the time:

“The first four or five years are almost entirely appropriated to the compounding of medicines; the art of which,with every habit of necessary exactness, might just as well be obtained in as many months. The remaining years of his apprenticeship bring with them the acquisition of the art of bleeding, of dressing a blister, and, for the completion of the climax – of exhibiting an enema” Parkinson, J. p32 (1800)

To further his training, James became one of the first medical students of the London Hospital Medical College (Whitechapel Road), founded by William Blizzard – surgeon of the Hospital. The college register records that he entered for training on Feb 20th 1776 when he was in his twentieth year. He was a ‘hospital pupil’ (or dresser) under Richard Grindall, FRS, at that time assistant surgeon. James remained for 6 months, but after this training he still felt ‘miserably ignorant’.

Richard Grindall (1716-1795) – by William Daniell, (21 Aug 1793) – Source

On 1st April 1784, James was examined and granted the grand diploma of the Company of Surgeons. He then joined his father in a practice, called “Parkinson and Son” (that practice was to last through 4 generations – approx. 80 years). Unfortunately, John Parkinson died only 6 years later, and James was left to manage the practice single-handedly. James was fortunate to take over his father’s prosperous practise as he noted that ‘a physician seldom obtains bread by his profession until he has no teeth left to eat it’. The clientele requiring the services of Parkinson and son, however, would change dramatically during James’s life. Parkinson’s and son’s evolved from a upper-middle class practise to an almost entirely working class practise by the time James passed on.

It says a great deal about the man that he did not move away from the community as it evolved (as many early inhabitants of Hoxton Square did).

On 21st May 1783, James married Mary Dale in St Leonard’s Church, by special license which was the custom of the upper and middle classes of that period. He was 25 and she was 23 years old. James’s friend Wakelin Welch Jr of Lympstone (Devon) acted as his best man (many years later, James’ book ‘Organic Remains of a Former World’ was dedicated to Welch).

According to the Family Pursuits website, Mary Dale (daughter of John Dale and Mary Hardy) was born 2nd September, 1757 in Shoreditch, Middlesex. Her family lived lived in Charles Square, Hoxton. Mary’s grandfather, Francis Dale (1650-1716), was an apothecary in Hoxton Old Town. He had three sons: Francis (also an apothecary), Thomas (1699-1750), and John (a silk merchant and Mary’s father). Her family not only had a medical history, but also geological. Mary’s grand uncle, Samuel Dale (1659-1739) was a keen botanist and one of the first to describe the fossils in the cliffs of Harwich (Essex).

Samuel Dale (1659-1739) – Source: The Essex Field Club

Thus the marriage was most likely a good fit for James. Mary Parkinson would live a long life, dying on 28 March 1838 of typhus fever (Gardner-Thorpe, 2013). Together with James, she had six children, key amongst them was John William Keys Parkinson (born 11th July, 1785) who apprenticed to his father and would later become the ‘Son’ in ‘Parkinson and Son’ (and ultimately John’s son James Keys Parkinson would follow in this process).

In the next post of this series, we will look at James’ early years as a physician and his foray into political radicalism.

ADHD and Parkinson’s disease

March 23, 2017March 30, 2017 ~ Simon ~ 26 Comments

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The chemical dopamine plays a critical role in Parkinson’s disease.

It is also involved with the condition Attention deficit hyperactivity disorder, and recently researchers have been looking at whether there are any links between the two.

In today’s post we will look at what Attention deficit hyperactivity disorder is, how it relates to Parkinson’s disease, and what new research means for the community.

Source: Huffington Post

We really have little idea about how Parkinson’s disease actually develops.

It could be kicked off by a virus or environmental factors or genetics…or perhaps a combination of these. We really don’t know, and it could vary from person to person.

There is a lot of speculation, however, as to what additional conditions could make one susceptible to Parkinson’s disease, even those conditions with early developmental onsets, such as autism (which we have previously written about – click here to see that post).

Recently researchers in Germany have asked if there is any connections between Parkinson’s and ADHD?

What is ADHD?

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental condition that begins in childhood and persists into adulthood in 60% of affected individuals.

It is classically characterised in the media by hyperactive children who struggle to concentrate and stay focused on what they are doing. They are often treated with drugs such as Methylphenidate (also known as ritalin). Methylphenidate acts by blocking a protein called the dopamine transporter, which is involved with reabsorbing the chemical dopamine back into the cell after it has performed it’s function.

1280px-Ritalin

Ritalin. Source: Wikipedia

So are there any connections between ADHD and Parkinson’s disease?

This is an interesting question.

While there have been no reported findings of increased (or decreased) frequency of Parkinson’s disease in people with ADHD (to our knowledge), there are actually several bits of evidence suggesting a connection between the two conditions, such as abnormalities in the substantia nigra:

substantia

Title: Structural abnormality of the substantia nigra in children with attention-deficit hyperactivity disorder
Authors: Romanos M, Weise D, Schliesser M, Schecklmann M, Löffler J, Warnke A, Gerlach M, Classen J, Mehler-Wex C.
Journal: J Psychiatry Neurosci. 2010 Jan;35(1):55-8.
PMID: 20040247 (This article is OPEN ACCESS if you would like to read it)

The substantia nigra is a structure in the brain where the dopamine neurons reside. In Parkinson’s disease, the dopamine neurons of the substantia nigra start to degenerate – 50% are lost by the time a person is diagnosed with the condition.

In this study, the researchers used a technique called echogenicity to examine the substantia nigra of 22 children with ADHD and 22 healthy controls. Echogenicity is the ‘ability to bounce an echo’. This sort of assessment measures the return of an ultrasound signal that is aimed at a structure.

The researchers found that the ADHD subjects had a larger substantia nigra area than the healthy controls – which apparently indicates dopamine dysfunction. This finding is similar to results that have been observed in Parkinson’s disease (Click here to read more regarding that study).

Another connection between the two conditions was recent research has shown that genetic variations in the PARK2 gene (also known as Parkin) contribute to the genetic susceptibility to ADHD.

Parkin title

Title: Genome-wide analysis of rare copy number variations reveals PARK2 as a candidate gene for attention-deficit/hyperactivity disorder.
Authors: Jarick I, Volckmar AL, Pütter C, Pechlivanis S, Nguyen TT, Dauvermann MR, Beck S, Albayrak Ö, Scherag S, Gilsbach S, Cichon S, Hoffmann P, Degenhardt F, Nöthen MM, Schreiber S, Wichmann HE, Jöckel KH, Heinrich J, Tiesler CM, Faraone SV, Walitza S, Sinzig J, Freitag C, Meyer J, Herpertz-Dahlmann B, Lehmkuhl G, Renner TJ, Warnke A, Romanos M, Lesch KP, Reif A, Schimmelmann BG, Hebebrand J, Scherag A, Hinney A.
Journal: Mol Psychiatry. 2014 Jan;19(1):115-21.
PMID: 23164820 (This article is OPEN ACCESS if you would like to read it)

There are about 20 genes that have been associated with Parkinson’s disease, and they are referred to as the PARK genes. Approximately 10-20% of people with Parkinson’s disease have a genetic variation in one or more of these PARK genes (we have discussed these before – click here to read that post). PARK2 is a gene called Parkin. Mutations in Parkin can result in an early-onset form of Parkinson’s disease. The Parkin gene produces a protein which plays an important role in removing old or sick mitochondria (we discussed this in our previous post – click here to read that post).

In this report, the researchers conducted a genetic sequencing study on 489 young subjects with ADHD (average age 11 years old) and 1285 control individuals. They replicated the study with a similar sized population of people affected by ADHD and control subjects, and in both studies they found that certain deletions and replications in the Parkin gene influences susceptibility to ADHD – two of the genetic variations were found in 335 of the ADHD cases and none in 2026 healthy controls (from both sets of studies).

So there are are some interesting possible connections between ADHD and Parkinson’s disease.

And what has the recent research from the German scientists found?

In this study, the researchers have looked at additional genetic variations that have been suggested to infer susceptibility to ADHD.

adhd

Title: No genetic association between attention-deficit/hyperactivity disorder (ADHD) and Parkinson’s disease in nine ADHD candidate SNPs
Authors: Geissler JM; International Parkinson Disease Genomics Consortium members., Romanos M, Gerlach M, Berg D, Schulte C.
Journal: Atten Defic Hyperact Disord. 2017 Feb 7. doi: 10.1007/s12402-017-0219-8. [Epub ahead of print]
PMID: 28176268

The researchers analysed nine genetic variations in seven genes:

one variant in the gene synaptosomal-associated protein, 25kDa1 (SNAP25)
one variant in the gene dopamine transporter (DAT; also known as SLC6A3)
one variant in the gene dopamine receptor D4 (DRD4)
one variant in the gene serotonin receptor 1B (HTR1B)
three mutations in cadherin 13 (CDH13)
one mutation located within the gene tryptophan hydroxylase 2 (TPH2)
one mutation located within the gene noradrenaline transporter (SLC6A2)

These genetic variations were assessed in 5333 cases of Parkinson’s disease and 12,019 healthy controls. The researchers found no association between any of the genetic variants and Parkinson’s disease. This finding lead the investigators to conclude that these genetic alterations associated with ADHD do not play a substantial role in increasing the risk of developing Parkinson’s disease.

Have ADHD medications ever been tested in Parkinson’s disease?

Yes.

Given the association of both ADHD and Parkinson’s disease with altered dopamine processing in the brain, a clinical trial of ritalin in Parkinson’s disease was set up and run in 2006 (Click here to read more about that trial). The results of the trial were published in 2007:

Ritalin title

Title: Effects of methylphenidate on response to oral levodopa: a double-blind clinical trial.
Authors: Nutt JG, Carter JH, Carlson NE.
Journal: Arch Neurol. 2007 Mar;64(3):319-23.
PMID: 17353373 (This article is OPEN ACCESS if you would like to read it)

In this study, the researchers recruited 12 people with Parkinson’s disease and examined their response to 0.4 mg/kg of ritalin – given 3 times per day – in conjunction with their normal anti-Parkinsonian medication (L-dopa). They then tested the subjects with either ritalin or a placebo control and failed to find any clinically significant augmentation of L-dopa treatment from the co-administration of ritalin.

What does it all mean?

So summing up: both Attention deficit hyperactivity disorder (ADHD) and Parkinson’s disease are associated with changes in the processing of the brain chemical dopamine. There are loose connections between the two conditions, but nothing definitive.

It will be interesting to follow up some of the individuals affected by ADHD, to determine if they ultimately go on to develop Parkinson’s (particularly those with Parkin mutations/genetic variants). But until then, the connection between these two conditions is speculative at best.

The banner for today’s post was sourced from Youtube

Resveratrol: From the folks who brought you Nilotinib

March 16, 2017 ~ Simon ~ 11 Comments

vc_spotlightsonoma_breaker_winegrapes_stock_rf_525141953_1280x640

Recently the results of a small clinical study looking at Resveratrol in Alzheimer’s disease were published. Resveratrol has long been touted as a miracle ingredient in red wine, and has shown potential in animal models of Parkinson’s disease, but it has never been clinically tested.

Is it time for a clinical trial?

In today’s post we will review the new clinical results and discuss what they could mean for Parkinson’s disease.

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From chemical to wine – Resveratrol. Source: Youtube

In 2006, there was a research article published in the prestigious journal Nature about a chemical called resveratrol that improved the health and survival of mice on a high-calorie diet (Click here for the press release).

Wine2
Title: Resveratrol improves health and survival of mice on a high-calorie diet.
Authors: Baur JA, Pearson KJ, Price NL, Jamieson HA, Lerin C, Kalra A, Prabhu VV, Allard JS, Lopez-Lluch G, Lewis K, Pistell PJ, Poosala S, Becker KG, Boss O, Gwinn D, Wang M, Ramaswamy S, Fishbein KW, Spencer RG, Lakatta EG, Le Couteur D, Shaw RJ, Navas P, Puigserver P, Ingram DK, de Cabo R, Sinclair DA.
Journal: Nature. 2006 Nov 16;444(7117):337-42.
PMID: 17086191 (This article is OPEN ACCESS if you would like to read it)

In this study, the investigators placed middle-aged (one-year-old) mice on either a standard diet or a high-calorie diet (with 60% of calories coming from fat). The mice were maintained on this diet for the remainder of their lives. Some of the high-calorie diet mice were also placed on resveratrol (20mg/kg per day).

After 6 months of this treatment, the researchers found that resveratrol increased survival of the mice and insulin sensitivity. Resveratrol treatment also improved mitochondria activity and motor performance in the mice. They saw a clear trend towards increased survival and insulin sensitivity.

The report caused a quite a bit of excitement – suddenly there was the possibility that we could eat anything we wanted and this amazing chemical would safe us from any negative consequences.

Grape

Source: Nature

That report was proceeded by numerous studies demonstrating that resveratrol could extend the life-span of various micro-organisms, and it was achieving this by activating a family of genes called sirtuins (specifically Sir1 and Sir2) (Click here, here and here for more on this).

Subsequent to these reports, there have been numerous scientific publications suggesting that resveratrol is capable of all manner of biological miracles.

Wow! So what is resveratrol?

grapes

Do you prefer your wine in pill form? Source: Patagonia

Resveratrol is a chemical that belongs to a group of compounds called polyphenols. They are believed to act like antioxidants. Numerous plants produce polyphenols in response to injury or when the plant is under attack by pathogens (microbial infections).

Fruit are a particularly good source of resveratrol, particularly the skins of grapes, blueberries, raspberries, mulberries and lingonberries. One issue with fruit as a source of resveratrol, however, is that tests in rodents have shown that less than 5% of the oral dose was observed as free resveratrol in blood plasma (Source). This has lead to the extremely popular idea of taking resveratrol in the form of wine, in the hope that it could have higher bioavailability compared to resveratrol in pill form. Red wines have the highest levels of Resveratrol in their skins (particularly Mabec, Petite Sirah, St. Laurent, and pinot noir). This is because red wine is fermented with grape skins longer than is white wine, thus red wine contains more resveratrol.

EDITOR’S NOTE: Sorry to rain on the parade, but it is important to note here that red wine actually contains only small amounts of resveratrol – less than 3-6 mg per bottle of red wine (750ml). Thus, one would need to drink a great deal of red wine per day to get enough resveratrol (the beneficial effects observed in the mouse study described above required 20mg/kg of resveratrol per day. For a person weighting 80kg, this would equate to 1.6g per day or approximately 250 750ml bottles).

We would like to suggest that consuming red wine would NOT be the most efficient way of absorbing resveratrol. And obviously we DO NOT recommend any readers attempt to drink 250 bottles per day (if that is even possible).

The recommended daily dose of resveratrol should not exceed 250 mg per day over the long term (Source). Resveratrol might increase the risk of bleeding in people with bleeding disorders. And we recommend discussing any change in treatment regimes with your doctor before starting.

So what did they find in the Alzheimer’s clinical study?

Well, the report we will look at today is actually a follow-on to published results from a phase 2/safety clinical trial that were reported in 2015:

Title: A randomized, double-blind, placebo-controlled trial of resveratrol for Alzheimer disease.
Authors: Turner RS, Thomas RG, Craft S, van Dyck CH, Mintzer J, Reynolds BA, Brewer JB, Rissman RA, Raman R, Aisen PS; Alzheimer’s Disease Cooperative Study.
Title: Neurology. 2015 Oct 20;85(16):1383-91.
PMID: 26362286 (This article is OPEN ACCESS if you would like to read it)

The researchers behind the study are associated with the Georgetown research group that conducted the initial Nilotinib clinical study in Parkinson’s disease (Click here for our post on this).

The investigators conducted a randomized, placebo-controlled, double-blind, multi-center phase 2 trial of resveratrol in individuals with mild to moderate Alzheimer disease. The study lasted 52 weeks and involved 119 individuals who were randomly assigned to either placebo or resveratrol 500 mg orally daily treatment.

EDITOR’S NOTE: We appreciate that is daily dose exceeds the recommended daily dose mentioned above, but it is important to remember that the participants involved in this study were being closely monitored by the study investigators.

Brain imaging and samples of cerebrospinal fluid (the liquid within which the brain sits) were collected at the start of the study and after completion of treatment.

The most important result of the study was that resveratrol was safe and well-tolerated. The most common side effect was feeling nausea and diarrhea in approximately 42% of individuals taking resveratrol (curiously 33% of the participants blindly taking the placebo reported the same thing). There was also a weight loss effect between the groups, with the placebo group gaining 0.5kg on average, while the resveratrol treated group lost 1kg on average.

The second important take home message is that resveratrol crossed the blood–brain barrier in humans. The blood brain barrier prevents many compounds from having any effect in the brain, but it does not stop resveratrol.

The investigators initially found no effects of resveratrol treatment in various Alzheimer’s markers in the cerebrospinal fluid. Not did they see any effect in brain scans, cognitive testing, or glucose/insulin metabolism. The authors were cautious about their conclusions based on these results, however, as the study was statistically underpowered (that is to say, there were not enough participants in the various groups) to detect clinical benefits. They recommended a larger study to determine whether resveratrol is actually beneficial.

While exploring the idea of a larger study, the researchers have re-analysed some of the data, and that brings us to the report we want to review today:

moussa

Title: Resveratrol regulates neuro-inflammation and induces adaptive immunity in Alzheimer’s disease.
Authors: Moussa C, Hebron M, Huang X, Ahn J, Rissman RA, Aisen PS, Turner RS.
Journal: J Neuroinflammation. 2017 Jan 3;14(1):1. doi: 10.1186/s12974-016-0779-0.
PMID: 28086917 (This article is OPEN ACCESS if you would like to read it)

In this report, the investigators conducted a retrospective study re-examining the cerebrospinal fluid and blood plasma samples from a subset of subjects involved in the clinical study described above. In this study, they only looked at the subjects who started with very low levels in the cerebrospinal fluid 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 disease. A fragment of this protein (called Aβ42) begin clustering in the brains of people with Alzheimer’s disease and as a result, low levels of Aβ42 in cerebrospinal fluid have been associated with increased risk of Alzheimer’s disease and considered a possible biomarker of the condition (Click here to read more on this).

The resveratrol study investigators collected all of the data from subjects with cerebrospinal fluid levels of Aβ42 less than 600 ng/ml at the start of the study. This selection criteria gave them 19 resveratrol-treated and 19 placebo-treated subjects.

In this subset re-analysis study, resveratrol treatment appears to have slowed the decline in cognitive test scores (the mini-mental status examination), as well as benefiting activities of daily living scores and cerebrospinal fluid levels of Aβ42.

One of the most striking results from this study is the significant decrease observed in the cerebrospinal fluid levels of a protein called Matrix metallopeptidase 9 (or MMP9) after resveratrol treatment. MMP9 is slowly emerged as an important player in several neurodegenerative conditions, including Parkinson’s disease (Click here to read more on this). Thus the decline observed is very interesting.

This re-analysis indicates beneficial effects in some cases of Alzheimer’s as a result of taking resveratrol over 52 weeks. The researchers concluded that the findings of this re-analysis support the idea of a larger follow-up study of resveratrol in people with Alzheimer’s disease.

Ok, but what research has been done on resveratrol in Parkinson’s disease?

Yes, good question.

One of the earliest studies looking at resveratrol in Parkinson’s disease was this one:

Reserv
Title: Neuroprotective effect of resveratrol on 6-OHDA-induced Parkinson’s disease in rats.
Authors: Jin F, Wu Q, Lu YF, Gong QH, Shi JS.
Journal: Eur J Pharmacol. 2008 Dec 14;600(1-3):78-82.
PMID: 18940189

In this study, the researchers used a classical rodent model of Parkinson’s disease (using the neurotoxin 6-OHDA). One week after inducing Parkinson’s disease, the investigators gave the animals either a placebo or resveratrol (at doses of 10, 20 or 40 mg/kg). This treatment regime was given daily for 10 weeks and the animals were examined behaviourally during that time.

The researchers found that resveratrol improved motor performance in the treated animals, with them demonstrating significant results as early as 2 weeks after starting treatment. Resveratrol also reduced signs of cell death in the brain. The investigators concluded that resveratrol exerts a neuroprotective effect in this model of Parkinson’s disease.

Similar results have been seen in other rodent models of Parkinson’s disease (Click here and here to read more).

Subsequent studies have also looked at what effect resveratrol could be having on the Parkinson’s disease associated protein alpha synuclein, such as this report:

PD-title

Title: Effect of resveratrol on mitochondrial function: implications in parkin-associated familiarParkinson’s disease.
Authors: Ferretta A, Gaballo A, Tanzarella P, Piccoli C, Capitanio N, Nico B, Annese T, Di Paola M, Dell’aquila C, De Mari M, Ferranini E, Bonifati V, Pacelli C, Cocco T.
Journal: Biochim Biophys Acta. 2014 Jul;1842(7):902-15.
PMID: 24582596 (This article is OPEN ACCESS if you would like to read it)

In this study, the investigators collected skin cells from people with PARK2 associated Parkinson’s disease.

What is PARK2 associated Parkinson’s disease?

PARK2 is a gene called Parkin. Mutations in Parkin can result in an early-onset form of Parkinson’s disease. The Parkin gene produces a protein which plays an important role in removing old or sick mitochondria.

Hang on a second. Remind me again: what are mitochondria?

We have previously written about mitochondria (click here to read that post). 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

You may remember from high school biology class that mitochondria are bean-shaped objects within the cell. They convert energy from food into Adenosine Triphosphate (or ATP). ATP is the fuel which cells run on. Given their critical role in energy supply, mitochondria are plentiful and highly organised within the cell, being moved around to wherever they are needed.

Another Parkinson’s associated protein, Pink1 (which we have discussed before – click here to read that post), binds to dysfunctional mitochondria and then grabs Parkin protein which signals for the mitochondria to be disposed of. This process is an essential part of the cell’s garbage disposal system.

Park2 mutations associated with early onset Parkinson disease cause the old/sick mitochondria are not disposed of correctly and they simply pile up making the cell sick. The researchers that collected the skin cells from people with PARK2 associated Parkinson’s disease found that resveratrol treatment partially rescued the mitochondrial defects in the cells. The results obtained from these skin cells derived from people with early-onset Parkinson’s disease suggest that resveratrol may have potential clinical application.

Thus it would be interesting (and perhaps time) to design a clinical study to test resveratrol in people with PARK2 associated Parkinson’s disease.

So why don’t we have a clinical trial?

Resveratrol is a chemical that falls into the basket of un-patentable drugs. This means that big drug companies are not interested in testing it in an expensive series of clinical trials because they can not guarantee that they will make any money on their investment.

There was, however, a company set up in 2004 by the researchers behind the original resveratrol Nature journal report (discussed at the top of this post). That company was called “Sirtris Pharmaceuticals”.

e4d4a0ddab6419c9de2bd8ca4f199e0c

Source: Crunchbase

Sirtris identified compounds that could activate the sirtuins family of genes, and they began testing them. They eventually found a compound called SRT501 which they proposed was more stable and 4 times more potent than resveratrol. The company went public in 2007, and was subsequently bought by the pharmaceutical company GlaxoSmithKline in 2008 for $720 million.

Sirtris_rm

Source: Xconomy

From there, however, the story for SRT501… goes a little off track.

In 2010, GlaxoSmithKline stopped any further development of SRT501, and it is believed that this decision was due to renal problems. Earlier that year the company had suspended a Phase 2 trial of SRT501 in a type of cancer (multiple myeloma) because some participants in the trial developed kidney failure (Click here to read more).

Then in 2013, GlaxoSmithKline shut down Sirtris Pharmaceuticals completely, but indicated that they would be following up on many of Sirtris’s other sirtuins-activating compounds (Click here to read more on this).

Whether any of those compounds are going to be tested on Parkinson’s disease is yet to be determined.

What we do know is that the Michael J Fox foundation funded a study in this area in 2008 (Click here to read more on this), but we are yet to see the results of that research.

We’ll let you know when we hear of anything.

So what does it all mean?

Summing up: Resveratrol is a chemical found in the skin of grapes and berries, which has been shown to display positive properties in models of neurodegeneration. A recent double blind phase II efficacy trial suggests that resveratrol may be having positive benefits in Alzheimer’s disease.

Preclinical research suggests that resveratrol treatment could also have beneficial effects in Parkinson’s disease. It would be interesting to see what effect resveratrol would have on Parkinson’s disease in a clinical study.

Perhaps we should have a chat to the good folks at ‘CliniCrowd‘ who are investigating Mannitol for Parkinson’s disease (Click here to read more about this). Maybe they would be interested in resveratrol for Parkinson’s disease.

ONE LAST EDITOR’S NOTE: Under absolutely no circumstances should anyone reading this material consider it medical advice. The material provided here is for educational purposes only. Before considering or attempting any change in your treatment regime, PLEASE consult with your doctor or neurologist. SoPD can not be held responsible for actions taken based on the information provided here.

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A yeast model of Parkinson’s disease

March 13, 2017March 13, 2017 ~ Simon ~ 4 Comments

yeast-cell

When I say the word ‘yeast’, you might think of making bread or beer.

One does not automatically think of Parkinson’s disease.

But yeast has actually been incredibly useful in enhancing our understanding of the genetics of Parkinson’s disease, and may well now provide us with novel treatments for the condition. In today’s post we will discuss how yeast research is leading the way for Parkinson’s disease.

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Prof Susan Lindquist. Source: WallStreetJournal

It was with sadness that we heard about the passing of Prof Susan Lindquist in October last year. She was truly a pioneer in the field of molecular biology. In addition to advancing our understanding of gene functioning in degenerative diseases like Parkinson’s disease and Alzheimer’s, she also started a company, Yumanity, which is currently testing new drugs to tackle these conditions. Hopefully her legacy will have enormous impact for the millions of people around the world struggling with these conditions.

And that legacy all started with a bold (some even called it ‘crazy’) idea.

It involved yeast.

What is yeast?

Quite possibly the earliest domesticated species, yeast is a single-celled microorganism, traditionally classified as a member of the fungus kingdom. The evolutionary lineage of yeast dates back hundreds of millions of years old and there are at least 1500 species of yeast (Source: Wikipedia).

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The cellular structure of yeast. Source: Biocourseware

More importantly, yeast is one of the most centrally important model organisms used in modern biological research, representing one of the most thoroughly researched organisms in the world.

We know more about the biology of yeast than we do about ourselves!

And this statement is made further evident as researchers use yeast to produce the world’s first synthetic organism (an organism for which the genome has been designed or engineered). By the end of 2017, the Synthetic Yeast 2.0 consortium plans to have produced a new form of yeast in which all 16 chromosomes will have been made in the lab (for more on this, read this STAT article).

Why do scientists like studying yeast?

The main reason is that yeast cells are very similar to human cells, but they grow a lot faster (human cells on average divide a rate of about once every 12 hours, while yeast cells divide every two hours). Yeast is similar to human cells in that it has all of the eukaryote structures, including a nucleus, cytoplasm, and mitochondria (eukaryote meaning a cell with a nucleus).

Yeast has played a fundamental role in many major scientific discoveries since the early 1900s. In 1907, German scientist Edward Buchner won the Nobel Prize in Chemistry for research involving yeast extract and fermentation. Ninety one years later (2006), Roger D. Kornberg won the same prize for his work on DNA transcription using yeast.

Yeast was the first eukaryote to have its genome (DNA) fully sequenced (in 1996). Yeast is literally leading the way in biological research.

So what has this got to do with Parkinson’s disease?

This is where Prof Susan Lindquist comes into the story.

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Source: Youtube

In the early 2000s, she suggested the idea of using yeast to look at neurodegenerative conditions like Parkinson’s disease. It was a wild concept. Talking to the New York Times in 2007, she said “Even people in my laboratory thought we were crazy to try to study neurodegenerative diseases with a yeast cell. It’s not a neuron”.

But they persevered and in 2003 they published this research report in the journal Science:

yeast

Title: Yeast genes that enhance the toxicity of a mutant huntingtin fragment or alpha-synuclein.
Authors: Willingham S, Outeiro TF, DeVit MJ, Lindquist SL, Muchowski PJ.
Journal: Science. 2003; 302(5651):1769-72.
PMID: 14657499

In this study, the researchers conducted a genome-wide screens of mutant genes in yeast to identify genes that enhanced the toxic effects of the mutant huntingtin gene or alpha-synuclein protein. That is to say, they randomly mutated (made un-operational) just one gene per yeast cell, and these yeast cells either had the mutant huntingtin gene (which causes the neurodegenerative condition of Huntington’s disease) or too much alpha synuclein (which causes protein clumping in the yeast cells). Using this approach, they could determine which genes were responsible for increasing the negative effects of the mutant huntington gene or the alpha synuclein protein.

Of the 4850 yeast genes that the researcher mutated (and can we just point out that that is A LOT of work!!!), 52 were identified that exaggerated the affect of the mutant huntingtin gene and 86 increased sensitivity to alpha-synuclein (curiously, only one mutant gene resulted in increased sensitivity to both).

When they looked at the known functions of 86 genes that were increasing the sensitivity to alpha synuclein, the researchers found that most of them were involved in the processes of lipid metabolism (the synthesis and degradation of lipids) and vesicle-mediated transport (this occurs at the tips of neural branches – where alpha synuclein is located). Alpha synuclein is known to be involved with lipid metabolism (Click here and here for more on this). This reenforced the belief with the researchers that yeast could be used to assess disease relevant pathways – this study gave them the ‘proof of concept’.

In addition, the majority of the genes had human ‘orthologs’ (genes in different species that evolved from a common ancestral gene), meaning that the findings of yeast studies could potentially be translated to higher order creatures, like humans. The researchers concluded that they had found cell autonomous genes that are relevant to Parkinson’s disease.

With the publication of this work, people in Prof Lindquist’s lab were probably thinking the idea wasn’t so crazy anymore.

And this first publication led to many more, such as this report which was published in the same journal in 2006:

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Title: Alpha-synuclein blocks ER-Golgi traffic and Rab1 rescues neuron loss in Parkinson’s models.
Authors: Cooper AA, Gitler AD, Cashikar A, Haynes CM, Hill KJ, Bhullar B, Liu K, Xu K, Strathearn KE, Liu F, Cao S, Caldwell KA, Caldwell GA, Marsischky G, Kolodner RD, Labaer J, Rochet JC, Bonini NM, Lindquist S.
Journal: Science. 2006 Jul 21;313(5785):324-8.
PMID: 16794039 (This article is OPEN ACCESS if you would like to read it)

In this study, the researchers doubled the amount of alpha synuclein that yeast cells produce and they observed that the cell stopped growing and started to die. They then looked at the earliest cellular events following theover production of alpha synuclein and they noticed that there was a blockage in the endoplasmic reticulum (ER)-to-Golgi vesicular trafficking.

Yes, I know what you are going to ask: What is ER-to-Golgi vesicular trafficking?

The endoplasmic reticulum (or ER) is a network of tubules connected to the nucleus. It is involved in the production of proteins and lipids, which are then transported to the Golgi apparatus which then modifies them, sorts them and and packs them into small bags called vesicles. These vesicles can then be taken to the cell membrane where the proteins are released to do their jobs.

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The ER to Golgi pathway. Source: Welkescience

Now the fact that too much alpha synuclein was blocking this pathway was interesting, but the researchers wanted to go further. They conducted another genome-wide screens of genes in yeast to identify genes that could rescue this blockage – BUT this time, instead of mutating genes, the researchers randomly over produced one protein (and there was 3000 of them!!!) in each cell. Because the overproduction of alpha synuclein kills the yeast cells, all the researchers had to do was wait until the end of the experiment and determine which protein was over produced in the surviving cells.

And this led them to a protein called RAB1.

RAB1 is a protein that is critical to the transportation of proteins in cells. The researchers next tested the ability of RAB1 to rescue dopamine cells in Drosophila (flies), Caenorhabditis elegans (microscopic worms), and cell culture models of Parkinson’s disease and they found that it was able to rescue the cells in all three cases. While this result was very interesting, it also provided full validation of the approach that Prof Lindquist and her colleagues were taking using yeast cells to find new therapies for neurodegenerative conditions, like Parkinson’s disease.

But Prof Lindquist and her colleagues didn’t stop there.

Over the next decade numerous research reports were published taking advantage of this approach, including these two reports which appeared back-to-back in the journal Science:

lindq1

Title: Identification and rescue of α-synuclein toxicity in Parkinson patient-derived neurons.
Authors: Chung CY, Khurana V, Auluck PK, Tardiff DF, Mazzulli JR, Soldner F, Baru V, Lou Y, Freyzon Y, Cho S, Mungenast AE, Muffat J, Mitalipova M, Pluth MD, Jui NT, Schüle B, Lippard SJ, Tsai LH, Krainc D, Buchwald SL, Jaenisch R, Lindquist S.
Journal: Science. 2013 Nov 22;342(6161):983-7.
PMID: 24158904

And:

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Title: Yeast reveal a “druggable” Rsp5/Nedd4 network that ameliorates α-synuclein toxicity in neurons.
Authors: Tardiff DF, Jui NT, Khurana V, Tambe MA, Thompson ML, Chung CY, Kamadurai HB, Kim HT, Lancaster AK, Caldwell KA, Caldwell GA, Rochet JC, Buchwald SL, Lindquist S.
Journal: Science. 2013 Nov 22;342(6161):979-83.
PMID: 24158909

In these reports, Prof Lindquist and colleagues tested whether some of the proteins that had come up in their various screens could actually have positive benefits in human cells, specifically induced pluripotent stem (iPS) cells (which we have discussed before – click here to read that post). The researchers grew brains cells (neurons and glial cells) from the iPS cells derived from people who suffered from Parkinson’s disease with dementia. These cells exhibited a number of features that indicated that they were not healthy. From their yeast screens, the researchers identified a protein called Nedd4 that reversed the pathologic features in these neurons.

Nedd4 is an E3 ubiquitin-protein ligase, which is a protein involved in the removal of old or damaged proteins from a cell. It is part of the garbage disposal process. Importantly, Nedd4 has been shown to label alpha synuclein for disposal (Click here to read more about this) and it is also present in Lewy Bodies – the circular clusters of proteins present in the brains of people with Parkinson’s disease. Importantly, it is a ‘druggable’ target. Nedd4 has been considered a therapeutic target for cancer (Click here to read more on this).

More recently (and following the passing of Prof Lindquist) the group has published two research reports back-to-back in the journal Cell Systems:

yeast-3

Title: Genome-Scale Networks Link Neurodegenerative Disease Genes to α-Synuclein through Specific Molecular Pathways.
Authors: Khurana V, Peng J, Chung CY, Auluck PK, Fanning S, Tardiff DF, Bartels T, Koeva M, Eichhorn SW, Benyamini H, Lou Y, Nutter-Upham A, Baru V, Freyzon Y, Tuncbag N, Costanzo M, San Luis BJ, Schöndorf DC, Barrasa MI, Ehsani S, Sanjana N, Zhong Q, Gasser T, Bartel DP, Vidal M, Deleidi M, Boone C, Fraenkel E, Berger B, Lindquist S.
Journal: Cell Syst. 2017 Jan 25. pii: S2405-4712(16)30445-8.
PMID: 28131822 (This article is OPEN ACCESS if you would like to read it)

And:

chung2

Title: In Situ Peroxidase Labeling and Mass-Spectrometry Connects Alpha-Synuclein Directly to Endocytic Trafficking and mRNA Metabolism in Neurons.
Authors: Chung CY, Khurana V, Yi S, Sahni N, Loh KH, Auluck PK, Baru V, Udeshi ND, Freyzon Y, Carr SA, Hill DE, Vidal M, Ting AY, Lindquist S.
Journal: Cell Syst. 2017 Jan 25. pii: S2405-4712(17)30002-9.
PMID: 28131823

In these reports, Prof Lindquist and colleagues systematically mapped out molecular pathways underlying the toxic effects of alpha-synuclein. They applied their yeast derived 332 genes that impact alpha-synuclein toxicity, and linked them to multiple Parkinson’s-associated genes and druggable targets, using software called TransposeNet.

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Source: Cell

The investigators then validated some of the connections in human iPS cells derived from people with Parkinson’s disease, confirming that some of the Parkinson’s disease-related genetic interactions observed in yeast are ‘conserved’ (that is maintained across evolution) to humans. And these findings fully vindicated Prof Lindquist’s ‘crazy’ idea of using yeast cells to investigate neurodegenerative disease.

In the second report, the researchers identified 225 proteins in close physical proximity to alpha-synuclein in neurons using a new technique (called ascorbate peroxidase (APEX) labeling – let’s just say it’s complicated, but if you’d like to read more about it, Click here). Many of those 225 proteins were well known to the researchers being involved with activities in vesicles and synaptic terminals, where alpha synuclein is often found. But the researchers also found microtubule-associated proteins (including tau) rubbing shoulders with alpha-synuclein, as well as proteins involved with mRNA binding, processing, and translation (which they were not expecting). Thus, not only has Prof Lindquist’s yeast model of Parkinson’s disease provided us with novel therapeutic targets, but also opened new avenues of research related to alpha synuclein functioning.

And there is now a ‘yeast’ biotech company?

It is called Yumanity.

yumanity-screenshot2

Yumanity. Source: ScientificAmerican

Started in December 2014, with $45 million in funding, Yumanity is focused on determining new targets for neurodegenerative conditions in yeast cells, testing those new targets in human cells, and then moving towards clinical trials with the best candidates. To date, they have not announced any clinical trial candidates, but they working on compounds that are targeting the NEDD4 pathway in Parkinson disease (discussed above). We will be watching this company with great interest.

So what does it all mean?

Back in the early 2000s, Prof Lindquist and her team asked a simple but strange question:

Can we use our knowledge of yeast genetics to study neurodegeneration?

We now know that the answer is ‘yes’. The small single cell organism that most of us associate with baking and beer, shares enough genetics with us that we can use it as an assay for investigating molecular pathways involved with diseases of the brain. And in the not so distant future, this simple little organism may be providing us with new treatments and therapies for those diseases.

As we suggested at the start of this post, Prof Lindquist has left an amazing legacy. If Yumanity can move a new drug into clinical trials for Parkinson’s disease, it will only further strengthen that legacy.

Susan Lee Lindquist – June 5, 1949 to October 27, 2016

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The Journal of Parkinson’s disease – special issue

March 7, 2017March 7, 2017 ~ Simon ~ Leave a comment

JPD_logo_editors

Our policy at the SoPD is not to advertise or endorse commercial products or services. This is to avoid any ethical or conflict of interest situations.

Every now and then, however, we see something that we believe will be of interest and value to the Parkinson’s community…aaand we bend our policy rule book.

Today the Journal of Parkinson’s disease released a “200 years of Parkinson’s disease” OPEN ACCESS special issue of their journal which highlights some of the major discoveries in the field of Parkinson’s disease research.

Critically, the articles provide insights into how the discoveries were made, and they are written by some of the biggest names in the Parkinson’s research community (many of whom were actually there when the discoveries were made).

The issue has articles dealing with topics including:

Click here to see all of the articles in this special issue.

We fully recommend readers take advantage of this OPEN ACCESS issue and learn about how some of these great discoveries were made.

Happy reading.

Full disclosure: The Journal of Parkinson’s disease is a product of IOS Press. The SoPD has not been approached by or made any offers to IOS Press or anyone at the Journal of Parkinson’s disease. We merely thought that the material in this particular OPEN ACCESS issue would be of interest to our readers.

The banner for today’s post was sourced from the Journal of Parkinson’s disease

New kiwi research in Parkinson’s disease

February 24, 2017February 27, 2017 ~ Simon ~ 1 Comment

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I really didn’t expect to be writing about Parkinson’s research being conducted in New Zealand again so quickly, but yesterday a new study was published which has a few people excited.

It presents evidence of how the disease may be spreading… using cells collected from people with Parkinson’s disease.

In today’s post we will review the study and discuss what it means for Parkinson’s disease.

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The South Island of NZ from orbit. Source: Sciencenews

We may have mentioned the protein Alpha synuclein once or twice on this blog.

For anyone familiar with the biology of Parkinson’s disease, alpha synuclein is a major player. It is either public enermy no.1 in the underlying pathology of this condition or else it is the ultimate ‘fall guy’, left standing in the crime scene holding the bloody knife.

Remind me, what is alpha synuclein?

Alpha synuclein is an extremely abundant protein in our brains – making up about 1% of all the proteins floating around in each neuron (one of the main types of cell in the brain).

In healthy brain cells, normal alpha synuclein is typically found just inside the surface of the membrane surrounding the cell body and in the tips of the branches extending from the cell (in structures called presynaptic terminals which are critical to passing messages between neurons).

And why is alpha synuclein important in Parkinson’s disease?

Genetic mutations account for 10-20% of the cases in Parkinson’s disease.

Five mutations in the alpha-synuclein gene have been identified which are associated with increased risk of Parkinson’s disease (A53T, A30P, E46K, H50Q, and G51D – these are coordinates for locations on the alpha synuclein gene). Rare duplication or triplication of the gene have also been associated with Parkinson’s disease.

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The structure of alpha synuclein protein – blue squares are mutations. Source: Mdpi

So genetically, alpha synuclein is associated with Parkinson’s disease. But it is also involved at the protein level.

In brains of many people with Parkinson’s disease, there are circular clumps of alpha synuclein (and other proteins) that collect inside cells. These clumps are called Lewy bodies. They are particularly abundant in areas of the brain that have suffered cell loss.

A lewy body (brown with a black arrow) inside a cell. Source: Cure Dementia

No one has ever seen the process of Lewy body formation, so all we can do is speculate about how these aggregates develop. Currently there is a lot of evidence supporting the idea that alpha synuclein can be passed between cells. Once inside the new cell, the alpha synuclein helps to seed the formation of new Lewy bodies, and this is how the disease is believed to progress.

The passing of alpha synuclein between brain cells. Source: Natur e

Exactly how alpha synuclein is being passed between cells is the topic of much research at the moment. There are many theories and some results implicating methods such as direct penetration, or via a particular receptor. Perhaps even by a small package called an exosome being passed between cells (see image above).

How this occurs in the Parkinson’s disease brain, however, is unknown.

And this (almost) brings us to the kiwi scientists.

Last years, a group of Swiss scientists demonstrated that alpha synuclein could be passed between cells via ‘nanotubes’ – tiny tubes connecting between cells. The outlined their observations and results in this article:

switzerland
Title: Tunneling nanotubes spread fibrillar α-synuclein by intercellular trafficking of lysosomes.
Authors: Abounit S, Bousset L, Loria F, Zhu S, de Chaumont F, Pieri L, Olivo-Marin JC, Melki R, Zurzolo C.
Journal: EMBO J. 2016 Oct 4;35(19):2120-2138.
PMID: 27550960

The researchers who conducted this study were interested in tunneling nanotubes.

Yes, I know, ‘What are tunneling nanotubes?’

Tunneling nanotubes (also known as Membrane nanotubes or cytoneme are long protrusions extending from one cell membrane to another, allowing the two cells to share their contents. They can extend for long distances, sometimes over 100 μm – 0.1mm, but that’s a long way in the world of cells!

nanotubes

Tunneling nanotubes (arrows). Source: Wikipedia (and PLOSONE)

Previous studies had demonstrated that tunneling nanotubes can pass different infectious agents (HIV for example – click here to read more on this), supporting the idea that these structures could be a general conduit by certain diseases could be spreading.

nanotubes

A tunneling nanotube between two cells. Source: Pasteur

In their study the Swiss researchers found that alpha synuclein could be transferred between brain cells (grown in culture) via tunneling nanotubes. In addition, following that process of transfer, the alpha synuclein was able to induce the aggregation (or clumping) of the alpha synuclein in recipient cells.

A particularly interesting finding was that alpha synuclein appeared to encourage the appearance of tunneling nanotubes (there were more tunneling nanotubes apparent when cells produced more alpha synuclein). And the alpha synuclein that was being transferred was being passed on in ‘lysosomal vesicles’ – these are the rubbish bags of the cell (lysosomal vesicles are used to take proteins away for degradation).

Paints a rather insidious picture of the ‘ultimate fall guy’ huh!

And that image was made worse by the results published by the kiwis last night:

maurice

Title: α-synuclein transfer through tunneling nanotubes occurs in SH-SY5Y cells and primary brain pericytes from Parkinson’s disease patients
Authors: Dieriks BV, Park TI, Fourie C, Faull RL, Dragunow M, Curtis MA.
Journal: Scientific Reports, 7, Article number: 42984
PMID: 28230073 (This article is OPEN ACCESS if you would like to read it)

In their study, the New Zealand scientists extended the Swiss research by looking at cells collected from people with Parkinson’s disease. The researchers took human brain pericytes, which were derived from the postmortem brains of people who died with Parkinson’s disease.

And before you ask: pericytes are cells that wrap around the cells lining small blood vessels. They are important to the development of new blood vessels and maintaining the structural integrity of microvasculature.

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A pericyte (blue) hugging a blood vessel (red). Source: Xvivo

Pericytes contain alpha synuclein precipitates like those seen in neurons, and the kiwi scientists demonstrated that pericytes too can transfer alpha synuclein via tunneling nanotubes to neighbouring cells – representing a non-neuronal method of transport.

They also found that the transfer through the tunneling nanotubes can be very rapid – within 30 seconds – and the transferred alpha synuclein can hang around for more than 72 hours, suggesting that it is difficult for the receiving cell to dispose of. The researchers did note that the transfer through tunneling nanotubes occurred only in small subset of cells, but that this could explain the slow progression of Parkinson’s disease over time.

What does it all mean?

In order for us to truly tackle Parkinson’s disease and bring it under control, we need to know how this slowly progressing neurodegenerative condition is spreading. Some researchers in New Zealand have provided evidence involving cells collected from people with Parkinson’s disease that indicates one method by which the disease could be passed from one cell to another.

Tiny tunnels between cells, allowing material to be shared, could explain how the disease slowly progresses. The scientists observed the Parkinson’s associated protein alpha synuclein being passed between cells and then hanging around for more than a few days.

This method of transfer was made more interesting because the New Zealand researchers reported that non-neuronal cells (Pericytes, collected from people with Parkinson’s disease) could also form tunneling nanotubes. This observation raises questions as to what role non-neuronal cells could be playing in Parkinson’s disease.

This line of questions will obviously be followed up in future research, as will efforts to determine if tunneling nanotubes are actually present in the human brain or simply biological oddities present only in the culture dish. Demonstrating nanotubes in the brain will be difficult, but it would provide us with solid evidence that this method of disease transfer could be a bonafide cause of disease spread.

We watch with interest for further work in this area.

FULL DISCLOSURE: The author of this blog is a kiwi… and proud of it. He is familiar with the researchers who have conducted this research, but has had no communication with them regarding the publishing of this post. He simply thought that the results of their study would be of interest to the Parkinson’s community.

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HIV and Parkinson’s disease

February 18, 2017February 19, 2017 ~ Simon ~ 5 Comments

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I was recently made aware of an interesting fact:

Approximately 5% of people with Human immunodeficiency virus (HIV) infections develop Parkinson’s disease-like features.

Why is this?

In today’s post we will try to understand what is going on, and what it may mean for Parkinson’s disease.

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HIV (in green) budding (being released) from a blood cell (lymphocyte). Source: Wikipedia

Ok, let’s start at the beginning:

What is HIV?

Human immunodeficiency virus (or HIV) – as the name suggests – is the virus.

It causes the infection which gives rise to Acquired Immune Deficiency Syndrome (or AIDS). AIDS is a progressive failure of the immune system – the body loses its ability to fight infections. Without treatment, average survival period after infection with HIV is between 9 – 12 years.

HIV can be spread by the transfer of bodily fluids, such as blood and semen. The World Health Organisation (WHO) has estimated that approximately 36.9 million people worldwide were living with HIV/AIDS at the end of 2014 (that is equivalent to the entire population of Canada!).

hi-virion-structure_en-svg

The structure of the HIV virus. Source: Wikipedia

Does HIV affect the brain?

Yes.

At postmortem examinations, less than 10% of the brains from HIV infected individuals are histologically normal (Source).

HIV is a member of the lentivirus family of viruses, which readily infect immune cells (such as blood cells). HIV can also infect other types of cells though, including those in the brain. HIV will usually enter the central nervous system within the first month following infection. It enters the brain via infected blood cells which come into contact with brain ‘immune system/helper’ cells such as microglia and macrophages at the blood-brain-barrier.

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How HIV enters the brain. Source: Disease Models and Mechanisms

HIV can also infect astrocytes (albeit at a lower frequency than microglia and macrophages), by direct cell-cell contact with infected T cells (blood cells) at the blood-brain-barrier (No. 1 in the image above). After infecting astrocytes, there is dysfunction in the astrocyte and it will no longer be so supportive to the local neurons (No. 2 in the image above). Once inside the brain, HIV-infected macrophages will allow for infection of other macrophages and microglia (No. 3 in the image above), and all together these HIV-infected astrocytes and microglia will cause damage to neurons by releasing viral proteins (two in particular, called Tat and gp120) and additional nasty chemicals which are bad for the neurons (No. 4 in the image above). Finally, as the disease progresses, the protective layer of the blood-brain-barrier becomes compromised and HIV-infected T cells eventually enter the brain and they cause damage to neurons by releasing pro-inflammatory chemicals (making the environment harsh for neurons).

There is remarkably little evidence of HIV actually infecting neurons (Click here for a review on this), so any cell loss in the brain that is associated with HIV does not result from neurons themselves being infected. This may be due to the fact that neurons do not have the HIV receptors (such as CD4) on their cell membrane. Similarly, oligodendrocytes (a supporting cell) does not appear to be easily infected by HIV. The bulk of the infected cells in the brain appear to be of the microglial, macrophage and astrocytes. And without these supporting cells doing their jobs in a normal fashion, it is easy to see how neurons can start dying off.

The severity, characteristics and distribution of HIV-induced injury in the brain varies greatly between affected individuals. It is most likely associated with the viral load (or the number of viral particles) in the brain, which can vary from a few thousand to more than a million copies per mL.

Do HIV-infected people show any signs of the virus entering the brain?

For the majority of people infected with HIV, this entry of the virus into the nervous system is neurologically asymptomatic (meaning they will not notice it), except for the occasional mild headache (for more on this read this review). As a result of the HIV virus entering the brain, however, many infected individuals will suffer from a specific set of neurological disorders, collectively called the AIDS dementia complex (ADC) (also known as HIV-associated cognitive/motor complex, or simply HIV dementia).

So how does HIV infection result in Parkinson’s disease-like features?

As we have suggested in the introduction to this post, on rare occasions (approximately 5% of cases), HIV-infected patients may present an illness virtually identical to Parkinson’s disease. More commonly, people with HIV will exhibit an increased sensitivity to dopamine receptor-blocking agents, such as drugs with a low potential for inducing Parkinsonism, (for example prochlorperazine and metoclopropamide).

The exact mechanism by which HIV infection results in Parkinson’s disease-like features is the subject of debate, but what is clear is that the basal ganglia (a structure involved in Parkinson’s disease) faces the brunt of the HIV infection in the brain. HIV-infected microglia and macrophage are most prominent in the basal ganglia when compared to other brain regions (Click here and here for more on this), and the basal ganglia is where the chemical dopamine from the midbrain is being released.

In addition, there are other changes in the brains of HIV infected people which may aid in the appearance of Parkinsonian features:

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Title: Increased frequency of alpha-synuclein in the substantia nigra in human immunodeficiency virusinfection.
Authors: Khanlou N, Moore DJ, Chana G, Cherner M, Lazzaretto D, Dawes S, Grant I, Masliah E, Everall IP; HNRC Group.
Journal: J Neurovirol. 2009 Apr;15(2):131-8.
PMID: 19115126 (This article is OPEN ACCESS if you would like to read it)

The researchers in this study used staining techniques to look at the amount of alpha synuclein – the Parkinson’s associated protein – in slices of brain tissue taken from postmortem autopsies of 73 HIV+ individuals aged between 50 and 76 years of age.

The presence of alpha synuclein in the substantia nigra (an area of the brain affected by Parkinson’s disease) was a lot higher in the HIV+ brains when compared with healthy control samples (16% of the HIV+ brains had high levels of alpha synclein vs 0% for the healthy brains).

Interestingly, nearly all of the brains analysed (35 out of 36 HIV+ brains) had high levels of the Alzheimer’s disease associated protein, beta amyloid (which again raises the question of whether beta amyloid could be playing a defensive role in infections – see our previous post on this). Also interesting, was that there was no correlation between these proteins being present and the age of the person at death – that is to say, older brains did not have more of these proteins when compared with younger brains.

There are also additional ways in which HIV could be causing Parkinson’s-like features, such as:

HIV has been shown to affect the protein levels of Parkinson’s disease associated proteins, such as DJ1 and Lrrk2 (Click here and here to read more on this).
HIV can, in some cases, increase the level of Dopamine transporter, which would reduce the levels of free floating dopamine in the brain (Click here to read more about this).

How is HIV treated?

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Treating HIV. Source: NPR

There is currently no cure for HIV infection.

There are, however, treatments which help to slow the virus down. These are called Anti-retroviral drugs (HIV is a retrovirus). There are different kinds of anti-retroviral drugs, which act at different stages of the HIV life cycle. Combinations of several anti-retroviral drugs (generally three or four) is known as ‘Highly Active Anti-Retroviral Therapy'(or HAART).

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Mechanism by which four classes of anti-retroviral drugs work against HIV. Source: Wikipedia

As the schematic image above highlights, there are many ways to slow down the HIV virus. For example, you can prevent it from attaching to a cell and fusing with the cell membrane (fusion inhibitors). By treating HIV infected people with multiple medications attacking different parts of the HIV life cycle, the virus has been slowed down.

Does HAART treatments for HIV help with these Parkinson’s-like features?

In some cases, the answer appears to be yes.

There are numerous case studies in the literature which demonstrate the alleviation of HIV-associated Parkinsonian symptoms with HAART, such as this report:

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Title: Parkinsonism as the presenting manifestation of HIV infection: improvement on HAART.
Authors: Hersh BP, Rajendran PR, Battinelli D.
Journal: Neurology. 2001 Jan 23;56(2):278-9.
PMID: 11160977

In this study the researchers described the case of a 37 year old man who developed Parkinson’s like features in the setting of an HIV infection, which were resolved after 1 year of HAART.

Over a period of 4 months, the man developed co-ordination issue, clumsiness and an irregular tremor in his right hand (there was, however, no resting tremor). He noted a generalised slowness and exhibited a tendency towards decreased right arm swinging. He also developed dystonia in the right hand/arm. Following L-dopa treatment (25/100; one tablet 3x per day) there was improvement in balance & co-ordination, speech, facial expression, and the tremor (L-dopa does appear to improve most cases of HIV-associated Parkinson’s-like features).

Six months after first displaying these Parkinsonian features (and two month after initiating L-dopa treatment), the subject was placed on HAART treatment. Four months later, he discontinued L-dopa treatment and 12 months after starting the HAART regime his Parkinsonian features were largely resolved.

More case studies of HAART alleviating HIV-associated Parkinsonisms can be found by clicking here and here.

What does this mean for Parkinson’s disease?

This post was written for the research community rather than people with Parkinson’s disease. I thought the fact that some people with HIV can start to have Parkinson’s like features was an interesting curiosity and wanted to share/spread the information.

Having said that, this post raises some really interesting questions, such as if a virus like HIV can have this effect on the brain, could other viruses be having similar effects? Could some cases of Parkinson’s disease simply be the result of a viral infection? Either multiple hits from a particular virus or different viruses each taking a varying toll over the course of a life time.

This idea would explain many of the curious features of Parkinson’s disease, such as:

the asymmetry of the symptoms (people with Parkinson’s usually have the disease starting on one side of the body.
the fact that some cells in the brain are more vulnerable to the disease than others (perhaps they are more receptive to a particular virus).
the protein clusterings in the cells (Lewy bodies may be defensive efforts against viral infections).

As we have previous mentioned, theories of viral causes for Parkinson’s have been circulating ever since the 1918 flu pandemic (Click here to read our previous post on this topic). About the same time as the influenza virus was causing havoc around the world, another condition began to appear called ‘encephalitis lethargica‘. This disease left many of the victims in a statue-like condition, both motionless and speechless – similar to Parkinson’s disease. Initially, it was assumed that the influenza virus was the causal factor, but more recent research has left us not so sure anymore.

The point is, however, perhaps it is time for us to re-examine the possibility of a viral agent being involved in the development of Parkinson’s disease.

There is new technology that allows us to determine the viral history of each individual from a simple blood test (Click here for more on this), so it would be interesting to compare blood samples from people with Parkinson’s disease with healthy controls to determine any differences.

In addition to the overall question of a viral role in Parkinson’s disease, there also remains the question of why only a small fraction of people with HIV are affected by Parkinsonisms. It could be interesting to genetically screen those people with HIV that exhibit Parkinsonisms and compare them with people with HIV that do not. Do those affected individuals have recognised Parkinson’s related genetic mutations? Or do they have novel genetic variations that could tell us more about Parkinson’s disease?

Food for thought. Would be happy to hear others thoughts.

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George H and Vascular Parkinsonism

February 7, 2017 ~ Simon ~ 10 Comments

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During Super Bowl 51, ex-president George HW Bush was visibly wheel chair bound. He has in fact been using motorised scooters and wheelchairs since 2012.

His doctors have indicated that he suffers from Vascular Parkinsonism.

In today’s post we will discuss what Vascular Parkinsonism is and how it differs from Parkinson’s disease.

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During a visit to the White house. Source: Heavy

An important concept to understand about the subject matter here:

Parkinsonism is a syndrome, while Parkinson’s is a disease.

A syndrome is a collection of symptoms that characterise a particular condition, while a disease is a pathophysiological response to internal or external factors. The term ‘Parkinsonism’ is an umbrella term that encompasses many conditions which share some of the symptoms of Parkinson’s disease.

There are many different types of Parkinsonism, such as:

Idiopathic Parkinson’s disease (the most common type of parkinsonism)
Progressive Supranuclear Palsy (PSP)
Corticobasal Degeneration (CBD)
Multiple System Atrophy (MSA)
Essential tremor
Vascular Parkinsonism
Drug-induced Parkinsonism
Dementia with Lewy bodies
Inherited Parkinson’s disease
Juvenile Parkinson’s disease

All of these conditions fall under the syndrome title of ‘Parkinsonism’, but are all considered distinct/separate diseases in themselves.

So what is Vascular Parkinsonism?

Vascular Parkinsonism was first described in 1929 by Dr Macdonald Critchley (King’s College Hospital, London).

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Macdonald Critchley. Source: Npgprints

vascularpd

Title: Arteriosclerotic Parkinsonism.
Author: Critchley, M.
Journal: Brain (1929) 52, 23–83
PMID: N/A (this article is accessible by clicking here)

It is estimated that approximately 3% to 6% of all cases of Parkinsonism may have a vascular cause. Vascular (or Arteriosclerotic) Parkinsonism is results from a series of small strokes in the basal ganglia area of the brain and can lead to the appearance of symptoms that look like Parkinson’s disease: slow movements, tremors, difficulty walking, and rigidity.

Walking problems are particularly prominent with Vascular Parkinsonism, as the lower half of the body is usually more affected than the upper half. Another sign of Vascular Parkinsonism can be a poor or no response to L-dopa treatment, as production of dopamine is not the problem. Using brain scanning techniques we can see that some people with Vascular Parkinsonism will have a normal Dopamine transporter (DAT) scan – which demonstrates appropriate levels of dopamine being released and reabsorbed in the striatum (the red-white areas in the image below).

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DAT-scan and MR images of 62-y-old male with Vascular Parkinsonism (A) and 62-y-old male with Parkinson’s disease (B). Source: JNM

The brain scans above are from a person with Vascular Parkinsonism (A) and another person with Parkinson’s disease (B). Firstly, note the reduced levels of red-white areas in the image (B) – this reduction is due to less dopamine is being released and reabsorbed in the striatum in Parkinson’s disease (as there are less dopamine fibres present). Compare that with the relatively normal levels of red-white areas in the image (A), indicating normal levels of dopamine turnover (suggesting dopamine fibres are still present). Next, look at the black and white image in panel (A) and you will see a red arrow pointing at damaged areas (darkened regions) of the striatum – indicative of mini strokes. A dopamine receptor scan may show a reduction in the levels of dopamine receptors as a result of the strokes, meaning that the released dopamine will not be having much effect.

Do we know what can cause the strokes associated with Vascular Parkinsonism?

The symptoms of Vascular Parkinsonism tend to appear suddenly and generally do not progress, unlike Parkinson’s disease. We don’t know for sure what causes the mini strokes associated with Vascular Parkinsonism, and it probably varies from person to person, In general, however, doctors believe that high blood pressure and diabetes are the most likely causal factors (heart disease may also play a role).

What does it all mean?

Some people of Parkinson’s disease may actually have Vascular Parkinsonism, which can result from mini strokes in the basal ganglia region of the brain. They will usually be unresponsive to L-dopa and have more motor issues with their lower half of the body.

While Ex-President George HW Bush’s situation is extremely unfortunate, it reminds us that not all forms of Parkinsonism are Parkinson’s disease – an important factor to keep in mind when considering treatment regimes. We have posted this information here to make the Parkinson’s community more aware of this form of Parkinsonism. Later in the year we will discuss another form of Parkinsonism.

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