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

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

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

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


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

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

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

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

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

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

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

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

So why is there a difference?

We don’t know.

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

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

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

And this is a very serious discussion point.

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

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

Is there any evidence to suggest this?

We are just speculating here, but yes there is.

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

So what else could be causing the cell death?

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

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Sydney. Source: Vagabond

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

Remind me again, what is Amyotrophic lateral sclerosis?

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

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

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

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The Ice bucket challenge. Source: Forbes

What is the protein associated with ALS?

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

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

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

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SOD1 protein structure. Source: Wikipedia

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

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

This week, the Aussie researchers published this research report:

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

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

Heck, it surprised us!

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

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

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

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

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

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

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

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

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

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

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

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

1995

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

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

Lewy-bodies

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

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

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

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

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

Two studies have addressed this question:

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

And then in 2001, a second analysis:

Genes2

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

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

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

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

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

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

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

And guess what? It did!

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

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

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

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

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

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

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

So what does it all mean?

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

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

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


The banner for today’s post was sourced from Pinterest

The Antibiotic and Parkinson’s: Oppsy, they got doxy!

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The general population are wrong to look up to scientists as the holders of the keys to some kind of secret knowledge that allows them to render magic on a semi-irregular basis.

All too often, the great discoveries are made by accident.

A while back, some researchers from Germany and Brazil made an interesting discovery that could have important implications for Parkinson’s disease. But they only made this discovery because their mice were feed the wrong food.

Today we’ll review their research and discuss what it could mean for Parkinson’s disease.


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Sir Alexander Fleming. Source: Biography

Sir Alexander Fleming is credited with discovering the antibiotic properties of penicillin.

But, as it is often pointed out, that the discovery was a purely chance event – an accident, if you like.

After returning from a two week holiday, Sir Fleming noticed that many of his culture dishes were contaminated with fungus, because he had not stored them properly before leaving. One mould in particular caught his attention, however, as it was growing on a culture plate with the bacteria staphylococcus. Upon closer examination, Fleming noticed that the contaminating fungus prevented the growth of staphylococci.

In an article that Fleming subsequently published in the British Journal of Experimental Pathology in 1929, he wrote, “The staphylococcus colonies became transparent and were obviously undergoing lysis … the broth in which the mould had been grown at room temperature for one to two weeks had acquired marked inhibitory, bactericidal and bacteriolytic properties to many of the more common pathogenic bacteria.”

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Penicillin in a culture dish of staphylococci. Source: NCBI

Fleming isolated the organism responsible for prohibiting the growth of the staphylococcus, and identified it as being from the penicillium genus.

He named it penicillin and the rest is history.

Fleming himself appreciated the serendipity of the finding:

“When I woke up just after dawn on Sept. 28, 1928, I certainly didn’t plan to revolutionise all medicine by discovering the world’s first antibiotic, or bacteria killer. But I guess that was exactly what I did.” (Source)

And this gave rise to his famous quote:

“One sometimes finds what one is not looking for” (Source)

While Fleming’s discovery of the antibiotic properties of penicillin was made as he was working on a completely different research problem, the important thing to note is that the discovery was made because the evidence came to prepared mind.

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Pasteur knew the importance of a prepared mind. Source: Thequotes

And this is the purpose of all the training in scientific research – not acquiring ‘the keys to some secret knowledge’, but preparing the investigator to notice the curious deviation.

That’s all really interesting. But what does any of this have to do with Parkinson’s disease?

Three things:

  1. Serendipity
  2. Prepared minds
  3. Antibiotics.

Huh?

Five years ago, a group of Brazilian and German Parkinson’s disease researchers made a serendipitous discovery:

While modelling Parkinson’s disease in some mice, they noticed that only two of the 40 mice that were given a neurotoxic chemical (6-OHDA) developed the motor features of Parkinson’s disease, while the rest remained healthy. This result left them scratching their heads and trying to determine what had gone wrong.

Then it clicked:

“A lab technician realised the mice had mistakenly been fed chow containing doxycycline, so we decided to investigate the hypothesis that it might have protected the neurons.” (from the press release).

The researchers had noted the ‘curious deviation’ and decided to investigate it further.

They repeated the experiment, but this time they added another group of animals which were given doxycycline in low doses (via injection) and fed on normal food (not containing the doxycycline).

And guess what: both group demonstrated neuroprotection!

Hang on a second. Two questions: 1. What exactly is 6-OHDA?
6-hydroxydopamine (or 6-OHDA) is one of several chemicals that researchers use to cause dopamine cells to die in an effort to model the cell death seen in Parkinson’s disease. It shares many structural similarities with the chemical dopamine (which is so severely affected in the Parkinson’s disease brain), and as such it is readily absorbed by dopamine cells who unwittingly assume that they are re-absorbing excess dopamine.

Once inside the cell, 6-OHDA rapidly transforms (via oxidisation) into hydrogen peroxide (H2O2 – the stuff folk bleach their hair with) and para-quinone (AKA 1,4-Benzoquinone). Neither of which the dopamine neurons like very much. Hydrogen peroxide in particular quickly causes massive levels of ‘oxidative stress’, resulting in the cell dying.
6OHDA

Transformation of the neurotoxin 6-OHDA. Source: NCBI

Think of 6-OHDA as a trojan horse, being absorbed by the cell because it looks like dopamine, only for the cell to work out (too late) that it’s not.

Ok, and question 2. What is doxycycline?

Doxycycline is an antibiotic that is used in the treatment of a number of types of infections caused by bacteria.

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Remind me again, what is an antibiotic?

Antibiotics are a class of drugs that either kill or inhibit the growth of bacteria. They function in one of several ways, either blocking the production of bacterial proteins, inhibiting the replication of bacterial DNA (nuclei acid in the image below), or by rupturing/inhibiting the repair of the bacteria’s outer membrane/wall.

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The ways antibiotics function. Source: FastBleep

So the researchers accidentally discovered that the a bacteria-killing drug called doxycycline prevented a trojan horse called 6-OHDA from killing dopamine cells?

Basically, yeah.

And then these prepared minds followed up this serendipitous discovery with a series of experiments to investigate the phenomenon further, and they published the results recently in the journal ‘Glial’:

Glial

Title: Doxycycline restrains glia and confers neuroprotection in a 6-OHDA Parkinson model.
Authors: Lazzarini M, Martin S, Mitkovski M, Vozari RR, Stühmer W, Bel ED.
Journal: Glia. 2013 Jul;61(7):1084-100. doi: 10.1002/glia.22496. Epub 2013 Apr 17.
PMID: 23595698

In the report of their research, the investigators noted that doxycycline significantly protected the dopamine neurons and their nerve branches (called axons) in the striatum – an area of the brain where dopamine is released – when 6-OHDA was given to mice. Both oral administration and peripheral injections of doxycycline were able to have this effect.

They also reported that doxycycline inhibited the activation of astrocytes and microglial cells in the brains of the 6-OHDA treated mice. Astrocytes and microglial cells are usually the helper cells in the brain, but in the context of disease or injury these cells can quickly take on the role of judge and executioner – no longer supporting the neurons, but encouraging them to die. The researchers found that doxycycline reduced the activity of the astrocytes and microglial cells in this alternative role, allowing the dopamine cells to recuperate and survive.

The researchers concluded that the “neuroprotective effect of doxycycline may be useful in preventing or slowing the progression of Parkinson’s disease”.

Wow, was this the first time this neuroprotective effect of doxycycline has been observed?

Curiously, No.

We have known of doxycycline’s neuroprotective effects in different models of brain injury since the 1990s (Click here, here and here for more on this). In fact, in their research report, the German and Brazilian researchers kindly presented a table of all the previous neuroprotective research involving doxycycline:

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And there was so much of it that the table carried on to a second page:

Table2

Source: Glia

And as you can see from the table, the majority of these reports found that doxycycline treatment had positive neuroprotective effects.

Is doxycycline the only antibiotic that exhibits neuroprotective properties?

No.

Doxycycline belongs to a family of antibiotics called ‘tetracyclines‘ (named for their four (“tetra-“) hydrocarbon rings (“-cycl-“) derivation (“-ine”)), and other members of this family have also been shown to display neuroprotection in models of Parkinson’s disease:

MPTP

Title: Minocycline prevents nigrostriatal dopaminergic neurodegeneration in the MPTP model ofParkinson’s disease.
Authors: Du Y, Ma Z, Lin S, Dodel RC, Gao F, Bales KR, Triarhou LC, Chernet E, Perry KW, Nelson DL, Luecke S, Phebus LA, Bymaster FP, Paul SM.
Journal: Proc Natl Acad Sci U S A. 2001 Dec 4;98(25):14669-74.
PMID: 11724929                    (This article is OPEN ACCESS if you would like to read it)

In this study, the researchers treated mice with an antibiotic called minocycline and it protected dopamine cells from the damaging effects of a toxic chemical called MPTP (or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine). MPTP is also used in models of Parkinson’s disease, as it specifically affects the dopamine cells, while leaving other cells unaffected.

The researchers found that the neuroprotective effect of minocycline is associated a reduction in the activity of proteins that initiate cell death (for example, Caspace 1). This left the investigators concluding that ‘tetracyclines may be effective in preventing or slowing the progression of Parkinson’s disease’.

Importantly, this result was quickly followed by two other research papers with very similar results (Click here and here to read more about this). Thus, it would appear that some members of the tetracycline class of antibiotics share some neuroprotective properties.

So what did the Brazilian and German researchers do next with doxycycline?

They continued to investigate the neuroprotective effect of doxycycline in different models of Parkinson’s disease. They also got some Argentinians and Frenchies involved in the studies. And these lines of research led to their recent research report in the journal Scientific Reports:

Doxy1
Title: Repurposing doxycycline for synucleinopathies: remodelling of α-synuclein oligomers towards non-toxic parallel beta-sheet structured species.
Authors: González-Lizárraga F, Socías SB, Ávila CL, Torres-Bugeau CM, Barbosa LR, Binolfi A, Sepúlveda-Díaz JE, Del-Bel E, Fernandez CO, Papy-Garcia D, Itri R, Raisman-Vozari R, Chehín RN.
Journal: Sci Rep. 2017 Feb 3;7:41755.
PMID: 28155912                (This article is OPEN ACCESS if you would like to read it)

In this study, the researchers wanted to test doxycycline in a more disease-relevant model of Parkinson’s disease. 6-OHDA is great for screening and testing neuroprotective drugs. But given that 6-OHDA is not involved with the underlying pathology of Parkinson’s disease, it does not provide a great measure of how well a drug will do against the disease itself. So, the researchers turned their attention to our old friend, alpha synuclein – the protein which forms the clusters of protein (called Lewy bodies) in the Parkinsonian brain.

What the researchers found was fascinating: Doxycycline was able to inhibit the disease related clustering of alpha synuclein. In fact, by reshaping alpha synuclein into a less toxic version of the protein, doxycycline was able to enhance cell survival. The investigators also conducted a ‘dosing’ experiment to determine the most effect dose and they found that taking doxycycline in sub-antibiotic doses (20–40 mg/day) would be enough to exert neuroprotection. They concluded their study by suggesting that these novel effects of doxycycline could be exploited in Parkinson’s disease by “repurposing an old safe drug”.

Wow, has doxycycline ever been used in clinical trials for brain-related conditions before?

Yes.

From 2005-12,there was a clinical study to determine the safety and efficacy of doxycycline (in combination with Interferon-B-1a) in treating Multiple Sclerosis (Click here for more on this trial). The results of that study were positive and can be found here.

More importantly, the other antibiotic to demonstrate neuroprotection in models of Parkinson’s disease, minocycline (which we mentioned above), has been clinically tested in Parkinson’s disease:

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Title: A pilot clinical trial of creatine and minocycline in early Parkinson disease: 18-month results.
Authors: NINDS NET-PD Investigators..
Journal: Clin Neuropharmacol. 2008 May-Jun;31(3):141-50.
PMID: 18520981                (This article is OPEN ACCESS if you would like to read it)

This research report was the follow up of a 12 month clinical study that can be found by clicking here. The researchers had taken two hundred subjects with Parkinson’s disease and randomly sorted them into the three groups: creatine (an over-the-counter nutritional supplement), minocycline, and placebo (control). All of the participants were diagnosed less than 5 years before the start of the study. At 12 months, both creatine and minocycline were noted as not interfering with the beneficial effects of symptomatic therapy (such as L-dopa), but a worrying trend began with subjects dropping out of the minocycline arm of the study.

At the 18 month time point, approximately 61% creatine-treated subjects had begun to take additional treatments (such as L-dopa) for their symptoms, compared with 62% of the minocycline-treated subjects and 60% placebo-treated subjects. This result suggested that there was no beneficial effect from using either creatine or minocycline in the treatment of Parkinson’s disease, as neither exhibited any greater effect than the placebo. In addition, the investigators suggested that the decreased tolerability of minocycline was a concern.

Ok, so where do I sign up for the next doxy clinical trial?

Well, the researchers behind the Scientific reports research (discussed above) are hoping to begin planning clinical trials soon.

But theoretically speaking, there shouldn’t be a trial.

Huh?!?

There’s a good reason why not.

In fact, if you look at the comments section under the research article, a cautionary message has been left by Prof Paul M. Tulkens of the Louvain Drug Research Institute in Belgium. He points out that:

“…using antibiotics at sub-therapeutic doses is the best way to trigger the emergence of resistance (supported by many in vitro and in vivo studies). Using an antibiotic for other indications than an infection caused by a susceptible bacteria is something that should be discouraged”

And he is correct.

We recklessly over use antibiotics all over the world at the moment and they are one of the few lines of defence that we have against the bacterial world. Long term use (which Parkinson’s disease would probably require) of an antibiotic at sub-therapeutic levels will only encourage the rise of antibiotic resistant bacteria (possibly within individuals).

The resistance of bacteria to antibiotics can occur spontaneously via several means (for example, through random genetic mutations during cell division). With the right mutation (inferring antibiotic resistance), an individual bacteria would then have a natural advantage over their friends and it would survive our attempts to kill it with antibiotics. Being resistant to antibiotic would leave that bacteria to wreak havoc upon us.

Its the purest form of natural selection.

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How bacteria become resistant to antibiotics. Source: Reactgroup

And antibiotic resistant bacteria are fast becoming a major health issue for us, with the number of species of bacteria developing resistance increasing every year (Click here for a good review on factors contributing to the emergence of resistance, and click here for a review of the antibiotic resistant bacteria ‘crisis’).

But don’t be upset on the Parkinson’s disease side of things. Prof Tulken adds that:

“If doxycycline really acts as the authors propose, the molecular targets are probably very different from those causing antibacterial activity. it should therefore be possible to dissociate these effect from the antibacterial effects and to get active compounds devoid of antibacterial activity This is where research must go to rather than in trying to use doxycycline itself.”

And he is correct again.

Rather than tempting disaster, we need to take the more prudent approach.

Independent researchers must now attempt to replicate the neuroprotective results in carefully controlled conditions. At the same time, chemists should conduct an analysis of the structure of doxycycline to determine which parts of it are having this neuroprotective effect.

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The structure of doxycycline. Source: Wikipedia

If researchers can isolate those neuroprotective elements and those same parts are separate from the antibiotic properties, then we may well have another experimental drug for treating Parkinson’s disease.

And the good news is that researchers are already reasonably sure that the mechanisms of the neuroprotective effect of doxycycline are distinct from its antimicrobial action.

So what does it all mean?

Researchers have once again identified an old drug that can perform a new trick.

The bacteria killing antibiotic, doxycycline, has a long history of providing neuroprotection in models of brain disease, but recently researchers have demonstrated that doxycycline may have beneficial effects on particular aspects of Parkinson’s disease.

Given that doxycycline is an antibiotic, we must be cautious in our use of it. It will be interesting to determine which components of doxycycline are neuroprotective, and whether other antibiotics share these components. Given the number of researchers now working in this area, it should not take too long.

We’ll let you know when we hear something.


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. While some of the drugs discussed on this website are clinically available, they may have serious side effects. We therefore urge caution and professional consultation before any attempt to alter a treatment regime. SoPD can not be held responsible for any actions taken based on the information provided here. 


The banner for today’s post was sourced from Youtube

On astrocytes and neurons – reprogramming for Parkinson’s

NG2+-flare

Last week scientists in Sweden published research demonstrating a method by which the supportive cells of the brain (called astrocytes) can be re-programmed into dopamine neurons… in the brain of a live animal!

It was a really impressive trick and it could have major implications for Parkinson’s disease.

In today’s post is a long read, but in it we will review the research leading up to the study, explain the science behind the impressive feat, and discuss where things go from here.


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Different types of cells in the body. Source: Dreamstime

In your body at this present moment in time, there is approximately 40 trillion cells (Source).

The vast majority of those cells have developed into mature types of cell and they are undertaking very specific functions. Muscle cells, heart cells, brain cells – all working together in order to keep you vertical and ticking.

Now, once upon a time we believed that the maturation (or the more technical term: differentiation) of a cell was a one-way street. That is to say, once a cell became what it was destined to become, there was no going back. This was biological dogma.

Then a guy in Japan did something rather amazing.

Who is he and what did he do?

This is Prof Shinya Yamanaka:

yamanaka-s

Prof Shinya Yamanaka. Source: Glastone Institute

He’s a rockstar in the scientific research community.

Prof Yamanaka is the director of Center for induced Pluripotent Stem Cell Research and Application (CiRA); and a professor at the Institute for Frontier Medical Sciences at Kyoto University.

But more importantly, in 2006 he published a research report demonstrating how someone could take a skin cell and re-program it so that was now a stem cell – capable of becoming any kind of cell in the body.

Here’s the study:

IPS2

Title: Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors.
Authors: Takahashi K, Yamanaka S.
Journal: Cell. 2006 Aug 25;126(4):663-76.
PMID: 16904174                (This article is OPEN ACCESS if you would like to read it)

Shinya Yamanaka‘s team started with the hypothesis that genes which are important to the maintenance of embryonic stem cells (the cells that give rise to all cells in the body) might also be able to cause an embryonic state in mature adult cells. They selected twenty-four genes that had been previously identified as important in embryonic stem cells to test this idea. They used re-engineered retroviruses to deliver these genes to mouse skin cells. The retroviruses were emptied of all their disease causing properties, and could thus function as very efficient biological delivery systems.

The skin cells were engineered so that only cells in which reactivation of the embryonic stem cells-associated gene, Fbx15, would survive the testing process. If Fbx15 was not turned on in the cells, they would die. When the researchers infected the cells with all twenty-four embryonic stem cells genes, remarkably some of the cells survived and began to divide like stem cells.

In order to identify the genes necessary for the reprogramming, the researchers began removing one gene at a time from the pool of twenty-four. Through this process, they were able to narrow down the most effective genes to just four: Oct4, Sox2, cMyc, and Klf4, which became known as the Yamanaka factors.

This new type of cell is called an induced pluripotent stem (IPS) cell – ‘pluripotent’ meaning capable of any fate.

The discovery of IPS cells turned biological dogma on it’s head.

And in acknowledgement of this amazing bit of research, in 2012 Prof Yamanaka and Prof John Gurdon (University of Cambridge) were awarded the Nobel prize for Physiology and Medicine for the discovery that mature cells can be converted back to stem cells.

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Prof Yamanaka and Prof Gurdon. Source: UCSF

Prof Gurdon achieved the feat in 1962 when he removed the nucleus of a fertilised frog egg cell and replaced it with the nucleus of a cell taken from a tadpole’s intestine. The modified egg cell then grew into an adult frog! This fascinating research proved that the mature cell still contained the genetic information needed to form all types of cells.

EDITOR’S NOTE: We do not want to be accused of taking anything away from Prof Gurdon’s contribution to this field (which was great!) by not mentioning his efforts here. For the sake of saving time and space, we are focusing on Prof Yamanaka’s research as it is more directly related to today’s post.

 

ips-cells

Making IPS cells. Source: learn.genetics

This amazing discovery has opened new doors for biological research and provided us with incredible opportunities for therapeutic treatments. For example, we can now take skins cells from a person with Parkinson’s disease and turn those cells into dopamine neurons which can then be tested with various drugs to see which treatment is most effective for that particular person (personalised medicine in it’s purest form).

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Some of the option available to Parkinson’s disease. Source: Nature

Imagination is literally the only limiting factor with regards to the possible uses of IPS cell technology.

Shortly after Yamanaka’s research was published in 2006, however, the question was asked ‘rather than going back to a primitive state, can we simply change the fate of a mature cell directly?’ For example, turn a skin cell into a neuron.

This question was raised mainly to address the issue of ‘age’ in the modelling disease using IPS cells. Researchers questioned whether an aged mature cell reprogrammed into an immature IPS cell still carried the characteristics of an aged cell (and can be used to model diseases of the aged), or would we have to wait for the new cell to age before we can run experiments on it. Skin biopsies taken from aged people with neurodegenerative conditions may lose the ‘age’ element of the cell and thus an important part of the personalised medicine concept would be lost.

So researchers began trying to ‘re-program’ mature cells. Taking a skin cell and turning it directly into a heart cell or a brain cell.

And this is probably the craziest part of this whole post because they actually did it! 

figure 1

Different methods of inducing skin cells to become something else. Source: Neuron

In 2010, scientists from Stanford University published this report:

Nature2

Title: Direct conversion of fibroblasts to functional neurons by defined factors
Authors: Vierbuchen T, Ostermeier A, Pang ZP, Kokubu Y, Südhof TC, Wernig M.
Journal: Nature. 2010 Feb 25;463(7284):1035-41.
PMID: 20107439

In this study, the researchers demonstrated that the activation of three genes (Ascl1, Brn2 and Myt1l) was sufficient to rapidly and efficiently convert skin cells into functional neurons in cell culture. They called them ‘iN’ cells’ or induced neuron cells. The ‘re-programmed’ skin cells made neurons that produced many neuron-specific proteins, generated action potentials (the electrical signal that transmits a signal across a neuron), and formed functional connection (or synapses) with neighbouring cells. It was a pretty impressive achievement, which they beat one year later by converting mature liver cells into neurons – Click here to read more on this – Wow!

The next step – with regards to our Parkinson’s-related interests – was to convert skin cells directly into dopamine neurons (the cells most severely affected in the condition).

And guess what:

PSNA

Title: Direct conversion of human fibroblasts to dopaminergic neurons.
Authors: Pfisterer U, Kirkeby A, Torper O, Wood J, Nelander J, Dufour A, Björklund A, Lindvall O, Jakobsson J, Parmar M
Journal:  Proc Natl Acad Sci U S A (2011) 108:10343-10348.
PMID: 21646515          (This article is OPEN ACCESS if you would like to read it)

In this study, Swedish researchers confirmed that activation of Ascl1, Brn2, and Myt1l re-programmed human skin cells directly into functional neurons. But then if they added the activation of two additional genes, Lmx1a andFoxA2 (which are both involved in dopamine neuron generation), they could convert skin cells directly into dopamine neurons. And those dopamine neurons displayed all of the correct features of normal dopamine neurons.

With the publication of this research, it suddenly seemed like anything was possible and people began make all kinds of cell types out of skin cells. For a good review on making neurons out of skin cells – Click here.

Given that all of this was possible in a cell culture dish, some researchers started wondering if direct reprogramming was possible in the body. So they tried.

And again, guess what:

Nature1

Title: In vivo reprogramming of adult pancreatic exocrine cells to beta-cells.
Authors: Zhou Q, Brown J, Kanarek A, Rajagopal J, Melton DA.
Journal: Nature. 2008 Oct 2;455(7213):627-32.
PMID: 18754011

Using the activation of three genes (Ngn3, Pdx1 and Mafa), the investigators behind this study re-programmed differentiated pancreatic exocrine cells in adult mice into cells that closely resemble b-cells. And all of this occurred inside the animals, while the animals were wandering around & doing their thing!

Now naturally, researchers in the Parkinson’s disease community began wondering if this could also be achieved in the brain, with dopamine neurons being produced from re-programmed cells.

And (yet again) guess what:

in-vivo

Title: Generation of induced neurons via direct conversion in vivo
Authors: Torper O, Pfisterer U, Wolf DA, Pereira M, Lau S, Jakobsson J, Björklund A, Grealish S, Parmar M.
Journal: Proc Natl Acad Sci U S A. 2013 Apr 23;110(17):7038-43.
PMID: 23530235         (This article is OPEN ACCESS if you would like to read it)

In this study, the Swedish scientists (behind the previous direct re-programming of skin cells into dopamine neurons) wanted to determine if they could re-program cells inside the brain. Firstly, they engineered skin cells with the three genes (Ascl1, Brn2a, & Myt1l) under the control of a special chemical – only in the presence of the chemical, the genes would be activated. They next transplanted these skin cells into the brains of mice and began adding the chemical to the drinking water of the mice. At 1 & 3 months after transplantation, the investigators found re-programmed cells inside the brains of the mice.

Next, the researchers improved on their recipe for producing dopamine neurons by adding the activation of two further genes: Otx2 and Lmx1b (also important in the development of dopamine neurons). So they were now activating a lot of genes: Ascl1, Brn2a, Myt1l, Lmx1a, FoxA2, Otx2 and Lmx1b. Unfortunately, when these reprogrammed cells were transplanted into the brain, few of them survived to become mature dopamine neurons.

The investigators then ask themselves ‘do we really need to transplant cells? Can’t we just reprogram cells inside the brain?’ And this is exactly what they did! They injected the viruses that allow for reprogramming directly into the brains of mice. The experiment was designed so that the cargo of the viruses would only become active in the astrocyte cells, not neurons. And when the researchers looked in the brains of these mice 6 weeks later, they found numerous re-programmed neurons, indicating that direct reprogramming is possible in the intact brain.

So what was so special about the research published last week about? Why the media hype?

The research published last week, by another Swedish group, took this whole process one step further: Not only did they re-program astrocytes in the brain to become dopamine neurons, but they also did this on a large enough scale to correct the motor issues in a mouse model of Parkinson’s disease.

Here is the study:
Arenas

Title: Induction of functional dopamine neurons from human astrocytes in vitro and mouse astrocytes in a Parkinson’s disease model
Authors: di Val Cervo PR, Romanov RA, Spigolon G, Masini D, Martín-Montañez E, Toledo EM, La Manno G, Feyder M, Pifl C, Ng YH, Sánchez SP, Linnarsson S, Wernig M, Harkany T, Fisone G, Arenas E.
Journal: Nature Biotechnology (2017) doi:10.1038/nbt.3835
PMID: 28398344

These researchers began this project 6 years ago with a new cocktail of genes for reprogramming cells to become dopamine neurons. They used the activation of NEUROD1, ASCL1 and LMX1A, and a microRNA miR218 (microRNAs are genes that produce RNA, but not protein – click here for more on this). These genes improved the reprogramming efficiency of human astrocytes to 16% (that is the percentage of astrocytes that were infected with the viruses and went on to became dopamine neurons). The researchers then added some chemicals to the reprogramming process that helps dopamine neurons to develop in normal conditions, and they observed an increase in the level of reprogramming to approx. 30%. And these reprogrammed cells display many of the correct properties of dopamine neurons.

Next the investigators decided to try this conversion inside the brains of mice that had Parkinson’s disease modelled in them (using a neurotoxin). The delivery of the viruses into the brains of these mice resulted in reprogrammed dopamine neurons beginning to appear, and 13 weeks after the viruses were delivered, the researchers observed improvements in the Parkinson’s disease related motor symptoms of the mice. The scientists concluded that with further optimisation, this reprogramming approach may enable clinical therapies for Parkinson’s disease, by the delivery of genes rather than transplanted cells.

How does this reprogramming work?

As we have indicated above, the re-programming utilises re-engineered viruses. They have been emptied of their disease causing elements, allowing us to use them as very efficient biological delivery systems. Importantly, retroviruses infect dividing cells and integrate their ‘cargo’ into the host cell’s DNA.

RetroviralIntegration

Retroviral infection and intergration into DNA. Source: Evolution-Biology

The ‘cargo’ in the case of IPS cells, is a copy of the genes that allow reprogramming (such as the Yamanaka genes), which the cell will then start to activate, resulting in the production of protein for those genes. These proteins subsequently go on to activate a variety of genes required for the maintenance of embryonic stem cells (and re-programming of mature cells).

And viruses were also used for the re-programming work in the brain as well.

There is the possibility that one day we will be able to do this without viruses – in 2013, researchers made IPS cells using a specific combination of chemicals (Click here to read more about this) – but at the moment, viruses are the most efficient biological targeting tool we have.

So what does it all mean?

Last week researchers is Sweden published research explaining how they reprogrammed some of the helper cells in the brains of Parkinsonian mice so that they turned into dopamine neurons and helped to alleviate the symptoms the mice were feeling.

This result and the trail of additional results outlined above may one day be looked back upon as the starting point for a whole new way of treating disease and injury to particular organs in the body. Suddenly we have the possibility of re-programming cells in our body to under take a new functions to help combat many of the conditions we suffer.

It is important to appreciate, however, that the application of this technology is still a long way from entering the clinic (a great deal of optimisation is required). But the fact that it is possible and that we can do it, raises hope of more powerful medical therapies for future generations.

As the researchers themselves admit, this technology is still a long way from the clinic. Improving the efficiency of the technique (both the infection of the cells and the reprogramming) will be required as we move down this new road. In addition, we will need to evaluate the long-term consequences of removing support cells (astrocytes) from the carefully balanced system that is the brain. Future innovations, however, may allow us to re-program stronger, more disease-resistant dopamine neurons which could correct the motor symptoms of Parkinson’s disease without being affected by the disease itself (as may be the case in transplanted cells – click here to read more about this).

Watch for a lot more research coming from this topic.


The banner for today’s post was sourced from Greg Dunn (we love his work!)

An Ambroxol update – active in the brain

Ambroxol-800x400

This week pre-clinical data was published demonstrating that the Ambroxol is active in the brain.

This is important data given that there is currently a clinical trial being conducted for Ambroxol in Parkinson’s disease.

Today’s post will review the new data and discuss what is happening regarding the clinical trial.


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Ambroxol. Source: Skinflint

We have previously discussed the potential use of Ambroxol in the treatment of Parkinson’s disease (Click here to read that post). Today we follow up that post with new data that provides further support for an on-going clinical trial.

Firstly, what is Ambroxol?

Ambroxol is a commonly used treatment for respiratory diseases (the respiratory system being the lungs and related components required for breathing). Ambroxol promotes the clearance of mucus and eases coughing. It also has anti-inflammatory properties, reducing redness in a sore throat. It is the active ingredient of products like Mucosolvan, Mucobrox, and Mucol.

 

What is the connection between Ambroxol and Parkinson’s disease?

So this is where a gene called GBA comes into the picture.

Genetic mutations in the GBA (full name: Glucosylceramidase Beta) gene are the most common genetic anomaly associated with Parkinson’s disease. People with a mutation in their GBA gene have a higher risk of developing Parkinson’s disease than the general population. And interestingly, people with Parkinson’s disease are approximately five times more likely to carry a GBA mutation than healthy control subjects.

What does GBA do?

The GBA gene provides the instructions for making an enzyme (called glucocerebrosidase) that helps with the digestion and recycling of waste inside cells. The enzyme is located and active inside ‘lysosomes‘.

What are Lysosomes?

Lysosomes are small bags of digestive enzymes that can be found inside cells. They help to break down proteins that have either been brought into the cell or that have served their function and need to be digested and disposed of (or recycled).

Lysosomes

How lysosomes work. Source: Prezi

Inside the lysosomes are enzymes like glucocerebrosidase which help to break material down into useful parts. The lysosome will fuse with other small bags (called vacuole) that act as storage vessels of material inside a cell. The enzymes from the lysosome will mix with the material in the vacuole and digest it (or it break down into more manageable components).

Now people with a genetic mutation in their GBA gene will often have an abnormally short, non-functioning version of the glucocerebrosidase enzyme. In those cases the breaking down of waste inside the lysosome becomes inhibited. And if waste can’t be disposed of or recycled properly, things start to go wrong in the cell.

How does Ambroxol correct this?

It was recently shown that Ambroxol triggers exocytosis of lysosomes (Source). Exocytosis is the process by which waste is exported out of the cell.

exocytosis

Exocytosis. Source: Socratic

Thus by encouraging lysosomes to undergo exocytosis and spit their contents out of the cell – digested or not – Ambroxol allows the cell to remove waste effectively and therefore function in a more normal fashion. This mechanism of treatment seemingly bi-passes the faulty glucocerebrosidase digestion enzyme entirely.

Until recently, two important questions, however, have remained unanswered:

  1. Does Ambroxol enter the brain and have this function there?
  2. What are the consequences of long term Ambroxol use?

We now have an answer for question no. 1:

Amb2

Title: Ambroxol effects in glucocerebrosidase and α-synuclein transgenic mice.
Authors: Migdalska-Richards A, Daly L, Bezard E, Schapira AH.
Journal: Ann Neurol. 2016 Nov;80(5):766-775.
PMID: 27859541            (This article is OPEN ACCESS if you would like to read it)

In this study, the researchers treated mice with Ambroxol for 12 days and then measured the level of glucocerebrosidase activity in the brain. They gave Ambroxol to three different groups of mice:

  • a group of normal mice,
  • a group of mice which had been genetically engineered with a specific mutation in their GBA gene (the heterozygous L444P mutation)
  • a group of mice that produced human alpha synuclein (the protein closely associated with Parkinson’s disease).

When they looked at the level of glucocerebrosidase enzyme activity in normal mice, they found an increase of approximately 20% (in mice treated with 4mM Ambroxol). One curious finding was that this dose was the only dose that increase glucocerebrosidase activity (1, 3, and 5mM of Ambroxol had no effect). The investigators noted, however, a reduction in water drinking of mice receiving 5mM in their drinking water (maybe they didn’t like the taste of it!), suggesting that they were not getting as much Ambroxol as the 4mM group.

The 4mM level of of Ambroxol also increased glucocerebrosidase activity in the L444P mutation mice and the alpha-synuclein mice (which interestingly also has reduced levels of glucocerebrosidase activity). One important observation in the alpha synuclein mice was the finding that Ambroxol was able to reduce the levels of alpha synuclein in the cells, indicating better clearance of un-wanted excess of proteins.

These combined results suggested to the investigators that Ambroxol is entering the brain of mice (passing through the protective blood brain barrier) and able to be effective there. In addition, they did not witness any serious adverse effects of ambroxol administration in the mice – an observation made in other studies of Ambroxol in normal mice (Click here to read more about this).

These studies have been followed up by a dosing study in primates which was just published:

Ambrox

Title: Oral ambroxol increases brain glucocerebrosidase activity in a nonhuman primate.
Authors: Migdalska-Richards A, Ko WK, Li Q, Bezard E, Schapira AH.
Journal: Synapse. 2017 Mar 12. doi: 10.1002/syn.21967.
PMID: 28295625            (This article is OPEN ACCESS if you would like to read it)

In this study, the investigators analysed the effect of Ambroxol treatment on glucocerebrosidase activity in three healthy non-human primates. One subject was given an ineffective control solution vehicle, another subject received 22.5 mg/day of Ambroxol and the third subject received 100 mg/day of Ambroxol. They showed that daily administration 100 mg/day of Ambroxol results in increased levels of glucocerebrosidase activity in the brain (approximately 20% increase on average across different areas of the brain). Importantly, the 22.5 mg treatment did not result in any increase.

The investigators wanted to determine if the effect of Ambroxol was specific to glucocerebrosidase, and so they analysed the activity of another lysosome enzyme called beta-hexosaminidase (HEXB). They found that 100 mg/day of Ambroxol also increased HEXB activity (again by approximately 20%), suggesting that Ambroxol may be having an effect on other lysosome enzymes and not just glucocerebrosidase.

The researches concluded that these results provide the first data of the effect of Ambroxol treatment on glucocerebrosidase activity in the brain of non-human primates. In addition, the results indicate that Ambroxol is active and as the researchers wrote “should be further investigated in the context of clinical trials as a potential treatment for Parkinson’s disease”.

And there is a clinical trial currently underway?

Yes indeed.

Funded by the Cure Parkinson’s Trust and the Van Andel Research Institute (USA), there is currently a phase I clinical trial with 20 people with Parkinson’s disease receiving Ambroxol over 24 months. Importantly, the participants being enrolled in the study have both Parkinson’s disease and a mutation in their GBA gene. The study is being led by Professor Anthony Schapira at the Royal Free Hospital (London).

EDITORS NOTE HERE: Readers may be interested to know that Prof Schapira is also involved with another clinical trial for GBA-associated Parkinson’s disease. The work is being conducted in collaboration with the biotech company Sanofi Genzyme, and involves a phase II trial, called MOVE-PD, which is testing the efficacy, and safety of a drug called GZ/SAR402671 (Click here to read more about this clinical trial). GZ/SAR402671 is a glucosylceramide synthase inhibitor, which will hopefully reduce the production and consequent accumulation of glycosphingolipids in people with a mutation in the GBA gene. This approach is trying to reduce the amount of protein that can not be broken down by the faulty glucocerebrosidase enzyme. The MOVE-PD study will enroll more than 200 patients worldwide (Click here and here to read more on this).

The current Phase 1 trial at the Royal Free Hospital will be primarily testing the safety of Ambroxol in GBA-associated Parkinson’s disease. The researchers will, however, be looking to see if Ambroxol can increase levels of glucocerebrosidase and also assess whether this has any beneficial effects on the Parkinson’s features.

So what does it all mean?

There is a major effort from many of the Parkinson’s disease related charitable groups to clinically test available medications for their ability to slow this condition. Big drug companies are not interested in this ‘re-purposing effort’ as many of these drugs are no longer patent protected and thus providing limited profit opportunities for them. This is one of the unfortunate realities of the pharmaceutical industry business model.

One of the most interesting drugs being tested in this re-purposing effort is the respiratory disease-associated treatment, Ambroxol. Recently new research has been published that indicates Ambroxol is able to enter the brain and have an impact by increasing the level of protein disposal activity.

A clinical trial testing Ambroxol in Parkinson’s disease is underway and we will be watching for the results when they are released (most likely late 2019/early 2020, though preliminary results may be released earlier).

This trial is worth watching.

Stay tuned.


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. Amboxol is a commercially available medication, but it is not without side effects (for more on this, see this website). We urge caution and professional consultation before altering a treatment regime. SoPD can not be held responsible for any actions taken based on the information provided here. 


The banner for today’s post was sourced from Pharmacybook

Stimulating research in London (Canada)

Spinal-Cord-final

Recently the SoPD has been contacted by readers asking about this video:

http://london.ctvnews.ca/video?clipId=1080895

The video presents a news article from Canada describing a clinical study of spinal cord stimulation for Parkinson’s disease.

In today’s post we review what spinal cord stimulation is and what research has been done in Parkinson’s disease.


 

should-say-50th-birthday-speech_67e6879f1e6fbd7

50 years celebration. Source: Reference

As many readers will be aware from 2017 represents the 200 year anniversary of the first description of Parkinson’s disease by one Mr James Parkinson.

Many readers will not be aware, however, that 2017 is also represents the 50th anniversary of the first use of a technique called spinal cord stimulation:

What is spinal cord stimulation?

Anterior_thoracic_SCS

An x-ray of the spine with a stimulator implanted (towards the top of the image, and cords leading off to the bottom left). Source: Wikipedia

A spinal cord stimulator involves a small device being used to apply pulsed electrical signals to the spinal cord. It is generally used for pain relief, but it has recently been tested in a variety of other medical conditions.

The device is a column of stimulating electrodes that is surgically implanted in the epidural space of the spine. And before you ask: the epidural space is the area between the outer protective skin of the spinal cord (called the dura mater) and the surrounding vertebrae. So the device lies against the spinal cord, and is protected by the bones that make up the spine (as shown in the image below).

stimimplanttrial_1280

The stimulating electrodes within the epidural space. Source: SpineOne

An electrical pulse generator is implanted in the lower abdomen and conducting wires are connected between the electrodes to the generator. Much like deep brain stimulation, the system is entirely enclosed in the body and operated with a remote control.

How does spinal cord stimulation work?

The stimulation basically interrupts the feeling of pain – blocking it from reaching the brain – substituting it with a more pleasing sensation called paresthesia (a kind of tingling or numbness).

PE-SCS Fig1

Source: MayoClinic

The stimulation does not eliminate the source of pain, it simply masks it by interfering with the signal going to the brain.  As a result the amount of relief from pain varies from person to person. In general, spinal cord stimulation resulting in a 50-70% reduction in pain.

But Parkinson’s results from inability to move, how would spinal cord stimulation work in Parkinson’s disease?

Yeah, this is a good question and the answer is not entirely clear, but the researchers (behind the research we discuss below) suggest that beneficial effects from spinal cord stimulation in Parkinson’s disease could be coming from direct activation of ascending pathways reaching thalamic nuclei and the cerebral cortex. That is to say (in plain English): activation of the spinal cord results in a signal going up into the brain where it alters the interaction between two of the regions involved in the initiation of movement (the thalamus and the cortex). And as we shall discuss below, there is evidence backing this idea.

Ok, so how much research has been done on spinal cord stimulation for Parkinson’s disease?

Actually quite a bit (in fact, for a good early review on the topic – click here).

The first real attempt at spinal cord stimulation for Parkinson’s disease was this report here:

Spinal1

Title: Spinal Cord Stimulation Restores Locomotion in Animal Models of Parkinson’s Disease
Authors: Fuentes, R., Petersson, P., Siesser, W. B., Caron, M. G., & Nicolelis, M. A. L.
Journal: Science (2009) 323(5921), 1578-1582.
PMID: 19299613                   (This article is OPEN ACCESS if you would like to read it)

It was conducted by Prof Miguel Nicolelis and his colleagues at Duke University. Duke were kind enough to make this short video about the research:

In their research report, the scientists injected mice with a drug that reduced the level of dopamine in the brain (the tyrosine hydroxylase inhibitor alpha-methyl-para-tyrosine  or AMPT). Similar to Parkinson’s disease, this resulted in a significant reduction in the movements of those mice. It also resulted in changes in the neuronal activity patterns of cells in an area of the brain called the motor cortex (we have talked about the motor cortex in a previous post). When the researchers then conducted spinal cord stimulation on these mice, they found that stimulation corrected both the loss of movement and the altered activity in the motor cortex.

The researchers then tested spinal cord stimulation in rats which had their dopamine system severely depleted (using the neurotoxin 6-OHDA), and they again found that the treatment could rescue the loss of locomotor ability. Curiously, spinal cord stimulation in the rats also caused an increase in locomotion activity after the stimulation period had stopped. On top of this, the researchers found that spinal cord stimulation aided the effect of L-dopa, allowing lower doses of L-dopa to achieve the same behavioural results as higher doses in animals not receiving spinal cord stimulation.

These initial results were then replicated in primates:

Monkey

Title: Spinal cord stimulation alleviates motor deficits in a primate model of Parkinson disease.
Authors: Santana MB, Halje P, Simplício H, Richter U, Freire MA, Petersson P, Fuentes R, Nicolelis MA.
Journal: Neuron. 2014 Nov 19;84(4):716-22.
PMID: 25447740              (This article is OPEN ACCESS if you would like to read it)

In this study, the researchers modelled Parkinson’s disease in five adult marmosets using the neurotoxin 6-OHDA, which resulted in a reduction in spontaneous behaviour and a significant loss of dopamine neurons in the brain. They then implanted a spinal cord stimulator in each of the animals, which once activated resulted in a 200% improvement in some aspects of behavioural activity. Improvements observed in Parkinson’s-like features included freezing (31%), hypokinesia (23%), posture (23%), and bradykinesia (21%) as calculated by investigators blind to the treatment conditions of each subject.

In the brain, the researchers found that spinal cord stimulation resulted in similar improvements in neural activity as that seen with L-dopa treatment. Given all of these results, the investigators concluded that spinal cord stimulation “should be further tested in clinical studies aimed at measuring its long-term efficacy as a less invasive, long-term therapy for” people with Parkinson’s disease.

And it was not just Prof Nicolelis’ group that has achieved these results. Japanese researchers have also reported spinal cord stimulation having beneficial effects in models of Parkinson’s disease:

NeuoroProtect

Title: Spinal cord stimulation exerts neuroprotective effects against experimental Parkinson’s disease.
Authors: Shinko A, Agari T, Kameda M, Yasuhara T, Kondo A, Tayra JT, Sato K, Sasaki T, Sasada S, Takeuchi H, Wakamori T, Borlongan CV, Date I.
Journal: PLoS One. 2014 Jul 10;9(7):e101468.
PMID: 25009993           (This article is OPEN ACCESS if you would like to read it)

In this report, the researchers actually found that spinal cord stimulation resulted in neuroprotection in a classical model of Parkinson’s disease (rodent 6-OHDA striatal delivery). Across three different levels of stimulation, the researchers reported better rescue of motor deficits and protection of dopamine neurons (particularly for 50Hz stimulation). The researchers also provided evidence suggesting that the neuroprotective effect might have something to do with a protein called Vascular endothelial growth factor (or VEGF). Interestingly, they found that the neuroprotective protein GDNF (that we have discussed before – click here for that post) was not involved.

So has this spinal stimulation procedure ever been conducted in humans with Parkinson’s disease before?

Yes, it has. But the results were a bit disappointing.

Stim1

Title: Spinal cord stimulation failed to relieve akinesia or restore locomotion in Parkinson disease.
Authors: Thevathasan W, Mazzone P, Jha A, Djamshidian A, Dileone M, Di Lazzaro V, Brown P.
Journal: Neurology. 2010 Apr 20;74(16):1325-7.
PMID: 20404313          (This article is OPEN ACCESS if you would like to read it)

In this very small clinical study, just two people (both 75+ years of age) with Parkinson’s disease were fitted with spinal cord stimulators. Ten days after the surgery, the subjects participated in a blind analysis of the motor effects of spinal stimulation (blind analysis meaning that the assessors were not aware of their surgical treatment). The assessors, however, found no improvements as a result of the stimulation treatment.

This report lead to a letter to the journal from Prof Nicolelis and his colleagues:

Neurol

In their letter, Prof Nicolelis and co point out several issues with the clinical study that may impact the final results (such as the tiny size of the study (only two participants) and the fact that the electrodes were located at a high cervical level, while in the rodent study they were located at a high thoracic level). In addition, the commercially available electrodes used in the human clinical study did not match the relative size or orientation of the electrodes used in the rodent study.

The researchers of the clinical study suggested that the beneficial motor effect described in the rodent study may be due to an increase in arousal (as a result of higher stimulation). But Prof Nicolelis and colleagues pointed out in their letter that their rodent study included three control experiments (including air puffs, trigeminal stimulation at the highest intensity tolerated by the animals, and direct measurements of changes in heart rate following spinal stimulation) which did not find a strong connection between arousal response and recovery seen in the level of locomotion.

The letter concluded that the results of the small clinical trial were inconclusive, and that further research in nonhuman primate models of Parkinson’s are required to determine the effects of electrode design and stimulation parameters. The doctors behind the clinical study agreed that more research is required.

And what do we know about this new clinical study?

Unfortunately, not very much.

The study is being conducted by Prof. Mandar Jog of Western University. Recently the Parkinson’s Society Southwestern Ontario provided some funding towards the study (Click here for more on this), but that is about as much as we could find on the work.

So what does it all mean?

Summing up: Spinal cord stimulation is a technique that is used to alleviate severe back pain. It has recently been proposed for Parkinson’s disease, resulting in several clinical trials. Here at the SoPD we are not sure what our opinion on spinal cord stimulation is at present, except that more research is obviously required.

If the results from the new clinical study (being conducted in Canada) indicate that spinal cord stimulation has beneficial effects for people with Parkinson’s disease, it would certainly represent a significant step forward for the community which relies heavily on symptom masking drugs at present. Before proceeding to wider clinical availability, however, larger clinical studies will be required to truly demonstrate safety and efficacy.

We’ll let you know if we hear anything else about this developing area of research.


The banner for today’s post was sourced from Greg Dunn

James: The man behind the disease (Part 1)

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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.

L0068467 The Villager's Friend and Physician

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.

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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-1746

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

Shoreditch

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

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

JP-Hoxton

 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 Leonards

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)

url

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’.

NPG D12199; Richard Grindall by William Daniell, after  George Dance

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).

 

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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.

A new theory of Parkinson’s disease

emc2

The great American baseball legend, Yogi Berra, once said: “In theory, there is no difference between theory and practice. But in practice, there is.”

Silly as it reads, there is a great deal of truth to that statement.

In science, we very quickly chase after a particular theory as soon as a little bit of evidence is produced that supports it. Gradually, these theories become our basic understanding of a situation, until someone points out the holes in the theory and we have to revise it.

A new theory of Parkinson’s disease has recently been proposed. In today’s post we will review what the theory is suggesting and what evidence there is to support it.


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“I still say it’s only a theory”. Source: NewYorker

In the age of ‘alternative facts’, it is always important to remember that we don’t know as much as we think we do. In fact, much of our modern world still relies on a kind of faith rather than actual ‘facts’. For example, we take a particular type of medicine, because it has worked for some people in the past, not because it will definitely make us better.

And the same applies to our understanding of neurodegenerative conditions, like Parkinson’s disease. Based on all the evidence we have collected thus far, we have theories of how Parkinson’s disease may be progressing. But there are always exceptions to the rule, and these force us to refine or reconsider our theories.

Recently a refinement to our theory of Parkinson’s disease has been suggested.

Who has suggested it?

This is Prof Ole Isacson.

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Source: Crunchbase

He’s a dude.

He is is a Professor of Neurology at Harvard Medical School, and Chief Scientific Officer of the Neuroscience Research Unit and Senior Vice President at the pharmaceutical company Pfizer.

And this is Dr Simone Engelender.

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Source: Rappaport

She’s awesome as well.

She is Associate Professor of Molecular Pharmacology at the Rappaport Family Institute for Research in the Medical Sciences in Haifa, Israel.

Together they have proposed a new theory of Parkinson’s disease that has the research community talking:

trends
Title: The Threshold Theory for Parkinson’s Disease.
Authors: Engelender S, Isacson O.
Journal: Trends Neurosci. 2017 Jan;40(1):4-14.
PMID: 27894611

The new theory proposes that Parkinson’s disease may actually be a ‘systemic condition’ (that is, affecting cells everywhere at the same time), but the clinical features – such as motor issues – only appear as certain thresholds are passed in the affected populations of neurons in the brain.

What does that mean?

Wait a minute. Let’s start at the beginning.

Before discussing what the new theory suggests, shall we first have a look at what the old theories proposed?

Ok, what did the old theory propose?

This is Prof Heiko Braak:

heiko-braak-01

Source – Memim.com

He’s pretty cool too. Nice guy.

Many years ago, Prof Braak – a German neuroanatomist – sat down and examined hundreds of postmortem brains from people with Parkinson’s disease.

He had collected brains from people at different stages of Parkinson’s disease – from just after being diagnosed to having had the condition for decades – and he was looking for any kind of pattern that might explain where and how the disease starts. His research led to what is referred to as the “Braak stages of Parkinson’s disease” – a six step explanation of how the disease spreads up from the brain stem and into the rest of the brain (Click here to read more about this).

nrneurol.2012.80-f1

The Braak stages of PD. Source: Nature

Braak’s results also led him to propose that Parkinson’s disease may actually begin in the brain stem (which connects the brain to the spinal cord) and the disease slowly works it’s way up into the brain.

That is the ‘ascending’ theory of Parkinson’s disease.

This idea has been further adapted by Braak and others with the discovery of Parkinson’s disease features in the gut (we have discussed this in previous posts – Click here and here to read those posts).

But how does the disease actually spread?

Good question.

The spread of the condition is believed to be due to the protein alpha synclein being passed between cells in some manner. This idea stemmed from the analysis of the brains of people with Parkinson’s disease who received cell transplantation therapy in the 1980-90’s. After those people passed away (due to natural causes), their brains were analysed and it was discovered that some of the cells in the transplants (1-5%) have Lewy bodies in them (Lewy bodies are one of the hallmarks of Parkinson’s disease, dense circular clusters of proteins including alpha synuclein). This suggests that the disease is passed on to the healthy transplanted cells in some way.

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Photos of neurons from the post-mortem brains of people with Parkinson’s that received transplants. White arrows in the images above indicate lewy bodies inside transplanted cells. Source: The Lancet

So the research community has been working with the idea of an ‘ascending’ theory of Parkinson’s disease, and the spreading of the condition via the passing of alpha synuclein from cell to cell. And this theory has been fine,…

Why do I feel like there’s a ‘but’ coming?

Because there is a ‘but’ coming.

And it’s a big BUT.

But as Prof Isacson and Dr Engelender point out there are some holes in this theory.

Some big holes.

For example, in a 2008 study of 71 postmortem brains from people with Parkinson’s disease, 47% of the cases did not fit the predicted ‘Braak theory’ spread of alpha synuclein, and 7% of those cases did not have any cell loss in the dorsal motor nucleus (one of the first sites of damage in the Braak theory – Click here to read more).

Ok, so the theory is not perfect…what are Prof Isacson and Dr Engelender proposing instead?

They suggest that alpha synuclein accumulation starts at about the same time in nerve cells throughout the body, but the different groups of nerve cell differ in how much toxicity they can handle.

Some of these groups of cells can handle a lot (and more than half of the cells need to be lost before clinical features begin to appear), while others have a lower ‘threshold’ (only a few cells need to die before symptoms appear).

Prof Isacson and Dr Engelender argue that the nerve cells around the gut, for example, have a lower reserve (or total number), and, therefore, symptoms related to the gut become more obvious sooner as those cells die off or become less efficient. This lower threshold is in contrast to the more well known cell loss of the dopamine producing neurons in the midbrain, where approximately 50-70 percent of the dopamine neurons disappear before the classical motor features of Parkinson’s start to appear. Their theory suggests that this part of the brain has a larger reserve, and thus higher threshold.

Hence the reason why this is being called the ‘threshold theory’.

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Some groups of cells may have a higher threshold in Parkinson’s disease. Source: Cell

Some cells may have a low threshold and only require a few cells to be lost before the clinical features associated with those cells begin to appear. These symptoms would obviously appear earlier than those features associated with a high threshold population of cells, which required substantial loss before symptoms appear.

This idea would explain differing results seen in research findings regarding, for example, vagotomies (the cutting of the vagus nerve to the gut – click here to read more about this). This new theory would suggest that the procedure might not have any impact at all on lowering the risk of Parkinson’s disease.

Both scientists insist that searching for treatments that slow or block the aggregation of alpha synuclein is still necessary.

“Instead of studying how proteins move from one neuron to another and searching for compounds that prevent the ‘spread’ of aggregated alpha-synuclein, we need to study why alpha-synuclein accumulates within neurons and how these neurons die in the disease, and search for compounds that prevent the general neuronal dysfunction,” – Dr Engelender

(Source: Science Daily)

So are there any problems with this new theory?

The new theory is a very interesting idea and deserves consideration. It solves some of the problems with the “ascending theory” discussed further above. But it also faces some of the same problems that the ascending theory has to deal with.

For example, in one large autopsy study which investigated 904 brains, the investigators blindly collected all of the brains that had alpha synuclein present in the groups of neurons that are affected in Parkinson’s disease (eg. the dorsal motor nucleus of vagus, substantia nigra, and/or basal forebrain nuclei.). They found that alpha synuclein was observed in 11.3% (or 106 cases). But when the researchers then looked at the clinical notes associated with those cases, only 32 (30%) had been diagnosed with a neurodegenerative disorder. The rest had demonstrated no clinical features.

Another study found that 8.3% of the aged control brains had alpha synuclein present in them. In addition, the presence of alpha synuclein is not specific to Parkinson’s disease – approximately 50% of people who die with Alzheimer’s disease have been found to have Lewy bodies. These results suggest that alpha synuclein aggregation can be present in both healthy and diseased brains. But if this is so, what role is alpha synuclein playing in Parkinson’s disease?

(You see the sort of problems we are dealing with in research when trying to come up with a theory of how something complicated is actually working?)

What does it all mean?

The central job of a scientist is to test hypotheses.

A hypothesis is a true or false statement (for example, hypothesis: the sun will come up tomorrow – easy to test as the sun either will or won’t come up; the statement is either true or false). In building one hypothesis on top of another hypothesis, we develop theories about how the world around us works.

Sometimes our hypotheses can unwittingly take us in a particular direction, depending on different variables. The danger in this process (one which must be met with discipline and control procedures) is that one can start to look for results that support a hypothesis or theory. It is a very human characteristic to become blind to any evidence to the contrary.

A new theory of Parkinson’s disease has been proposed. It suggests that rather than the condition starting in one location and progressively moving higher into the brain, Parkinson’s disease may actually start everywhere and it is the varying levels of tolerance between different types of cells that determines which cells die first.

It is certainly a new take of the available evidence and the research community is considering it. It will be interesting to see what kind of feedback results from this article, and we will post updates on that feedback as they become available.


The banner for today’s post was sourced from Sott

The red headed mice of Boston

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Recently scientists have found a possible link in the curious relationship of red hair, melanoma and Parkinson’s disease.

It involves red headed mice (not a typo – you read that correctly).

In today’s post we will discuss the new research and explain what it means for Parkinson’s disease.


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Red or ginger hair. Source: theLocal

We have previously discussed the curious association between red hair and Parkinson’s disease (Click here for that post).

We have also previously discussed the curious association between melanoma and Parkinson’s disease (Click here for that post).

Melanoma

Melanoma. Source: Wikipedia

Basically, people with red hair are more vulnerable to Parkinson’s disease that dark haired people, and people with a history of melanoma (skin cancer) are more likely to develop Parkinson’s disease than people with no history.

And given that people with red hair are generally more vulnerable to melanoma that dark haired people, you can understand why scientists have recently been very interested in this curious triangle of seemingly unrelated biological features.

Recently, however, scientists in Boston (USA) have provided evidence that the genetic mutation which causes red hair and increases the risk of melanoma, might also make the brain more vulnerable to Parkinson’s disease.

Red hair is caused by a genetic mutation?

Before we answer this question: the word ‘mutation’ carries a negative connotation thanks to it’s use in popular media and films. In biology, researchers prefer to use the word genetic ‘variation’. And EVERYONE has variations. They are what makes each of us unique. A father will pass on many of his own genetic variations to his son, but there will also be 50-100 spontaneous variations. And this is how, red hair can sometimes pop up in a family with little history of it.

Ok, so red hair is caused by a genetic variation?

Yes.

Red hair, which occurs naturally in 1–2% of the general population (though there are some regional/geographical variation), results from one of several genetic variations. Approximately 80% of people with red hair have a variation in a gene called melanocortin-1 receptor (or MC1R). Another gene associated with red hair is called HCL2 – ‘Hair colour 2’.

So what did the researchers find?

red

Title: The melanoma-linked “redhead” MC1R influences dopaminergic neuron survival.
Authors: Chen X, Chen H, Cai W, Maguire M, Ya B, Zuo F, Logan R, Li H, Robinson K, Vanderburg CR, Yu Y, Wang Y, Fisher DE, Schwarzschild MA.
Journal: Ann Neurol. 2016 Dec 26. doi: 10.1002/ana.24852. [Epub ahead of print]
PMID: 28019657

In their study, the researchers have investigated mice that carry a mutation of the MC1R gene (thus inactivating the gene – and yes, these mice have red/ginger fur!). They noticed that the mice displayed a progressive decline in their locomotor activity, moving around significantly less than non-red furred control mice at 8 months of age. The MC1R mutant mice also displayed a reduction in the number of dopamine producing neurons in the brain, when compared to the non-red furred controls (dopamine a chemical in the brain that helps to regulate movement).

The MC1R mutant mice were more vulnerable to toxin induced models of Parkinson’s disease (both 6OHDA and MPTP), but (most interestingly) when the researchers used a substance that binds to MC1R and initiates a response (an MC1R agonist called BMS-470539) they found that this treatment improved the survival of the dopamine producing cells in the brain.

The researchers are now seeking to further understand how the loss of MC1R renders the dopamine cells more vulnerable, and follow up the finding that MC1R agonists are neuroprotective.

Has there ever been any other evidence to suggest that MC1R is neuroprotective?

No. To our knowledge this is the first evidence that targeting MC1R could be a novel therapeutic strategy in a brain related condition (there has been some evidence of MC1R activation having beneficial effects in other parts of the body – click here for more on this).

And there are some indications as to how this positive effect could be working:

nurr1-2
Title: Melanocortin-1 receptor signaling markedly induces the expression of the NR4A nuclear receptor subgroup in melanocytic cells.
Authors: Smith AG, Luk N, Newton RA, Roberts DW, Sturm RA, Muscat GE.
Journal: J Biol Chem. 2008 May 2;283(18):12564-70.
PMID: 18292087

In this study, the researchers found that activating MC1R increases the levels of a protein called NR4A2 (or Nurr1). Nurr1 is a protein involved in the development and maintenance of dopamine producing neurons, and numerous recent studies have suggested that it is neuroprotective for these cells as well (Click here to read more on this).

So what does it all mean?

For some time there has been a curious link between people with red hair, melanoma and Parkinson’s disease. Now researchers in Boston have provided new evidence that the link exists, but they have also highlighted a new pathway via which novel therapies for Parkinson’s disease might be researched and developed.  Not a bad day at the office.


The banner for today’s post was sourced from Fancy mice

New kiwi research in Parkinson’s disease

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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.

Fig2_v1c

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.

Mechanism of syunuclein propagation and fibrillization

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

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.


The banner for today’s post was sourced from Pinterest

The Dogfish solution for Parkinson’s

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This week an interesting study was published in the scientific journal, Proceedings of the National Academy of SciencesIt involved our old friend, alpha synuclein – the aggregating protein that is associated with Parkinson’s disease – and the dogfish shark.

Not natural dance partners, I agree. But the findings of the study are very interesting.

In today’s post we will review the study and explain the connection between the protein and the shark.


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Source: Discovery

Some people call them spiny dogfish.

Others call them Spurdogs. Or Mud shark. Or even Piked dogfish.

Call them what you will – in the scientific realm they are referred to as Squalus acanthias. They are one of the most common members of the Squalide (dogfish) family of sharks. In the wild, Squalus acanthias are found in shallow waters, but can be seen further offshore in more temperate latitudes. They are relatively harmless to humans, but they do have venom in their rear fin – when under attack, the dogfish shark will arch its back and pierce/poison its attacker (so beware!).

Interesting, but what is the connection with Parkinson’s disease?

Good question.

So here’s the thing about dogfish sharks: they are extremely hardy when it comes to infection.

They don’t really get sick all that often. And this is despite having a relatively “primitive” immune system (Click here to read more on this). A team led by Prof Michael Zasloff (of Georgetown University) discovered that a chemical called ‘Squalamine’ may be one of the reasons for this robustness.

What is Squalamine?

Squalamine is steroid with a wide range of antimicrobial activity. Steroids are used as a treatment for certain inflammatory conditions, but the research published this week suggests another property for Squalamine.

This is the research article that was published:

pnas-dobson

Title: A natural product inhibits the initiation of α-synuclein aggregation and suppresses its toxicity
Authors: Perni M, Galvagnion C, Maltsev A, Meisl G, Müller MB, Challa PK, Kirkegaard JB, Flagmeier P, Cohen SI, Cascella R, Chen SW, Limboker R, Sormanni P, Heller GT, Aprile FA, Cremades N, Cecchi C, Chiti F, Nollen EA, Knowles TP, Vendruscolo M, Bax A, Zasloff M, Dobson CM.
Journal: PNAS 2017; doi:10.1073/pnas.1610586114
PMID: 28096355             (this article is OPEN ACCESS if you would like to read it)

In this study, the researchers discovered that squalamine can actually block alpha synuclein from aggregating (that is clumping together). They treated human cells (that produce too much alpha synuclein, which ultimately kills them) in culture with squalamine and they observed an almost complete suppression of the toxic effect of alpha synuclein.

c_elegans

Caenorhabditis elegans – cute huh? Source: Nematode

The researchers next looked at the effects of squalamine in a microscopic worm called Caenorhabditis elegans . These tiny creatures are widely used in biology because they can be easily genetically manipulated and their nervous system is very simple and well mapped out (they have just 302 neurons and 56 glial cells!). The particular strain of Caenorhabditis elegans used in this current study produced enormous amounts of alpha synuclein, which results in muscle paralysis.

By treating the worms with squalamine, the researchers observed a dramatic reduction of alpha synuclein protein aggregating and an almost complete elimination of the muscle paralysis. In addition, they noted a reduction in the cellular damage caused by the aggregation of alpha synuclein. All in all, a pretty impression result! The researchers suggested that their findings indicate that “squalamine could be a means of therapeutic intervention in Parkinson’s disease”.

So is squalamine being tested in the clinic?

The answer is: Yes, but not for Parkinson’s disease.

There is currently a clinical trial for squalamine in people with neovascular age-related macular degeneration – a condition of the eye (click here for more information about that trial). This work is being carried out by a company called Ohr Pharmaceuticals and as far as we are aware all of their work is focused on eye treatments. Squalamine has also been tested in clinical studies of fungal infection of the scalp – tinea capitis – and appeared to be well tolerated (Click here for more information).

Regarding Parkinson’s disease, there is just one small problem:

Squalamine doesn’t cross the blood-brain barrier
(click here to read more on this)

The blood brain barrier is a membrane that covers and protects the brain. It limits what chemicals can enter (or leave) the brain. Squalamine is one chemical that the blood brain barrier won’t let into the brain.

But this is not the end of the world!

Prof Zasloff and colleagues have designed a drug very similar to Squalamine, which they have called MSI-1436 which is currently being tested. And the good news is that it can cross the blood brain barrier (Click here to read more on this). MSI-1436 appears to exhibit potent appetite suppression and anti-diabetic properties when injected in animals. MSI-1436 has been clinically tested (phase 1) for tolerance in diabetes with obesity (Click here to see the details of that trial), but that clinical trial was conducted in 2008-9 and the results are still not available. The company behind the trial, ‘Genaera Corp’, has since been shut down (Click here for more on this), and we are unaware of any follow up clinical work on this drug.

What does it all mean?

Well, the researchers in this study have found a chemical (squalamine) which is able to prevent alpha synuclein from aggregating – which is believed to be one the underlying processes in Parkinson’s disease. This means that we have another experimental therapy to add to the growing arsenal of potential future Parkinson’s disease treatments.

It is important to appreciate, however, that this is the first time this result has been shown and what we need to see now is independent replication of these results. This follow-up work will also need to involve squalamine being tested in a more advanced animal model of Parkinson’s disease (worms are cute and all, but there is only so much data we can get from them!). In addition, if squalamine (or MSI-1436) has a future in treating Parkinson’s disease, we will need to better investigate the weight-loss properties of this chemical as this would not be an ideal side effect for people with Parkinson’s disease.

As this research progresses on squalamine, we’ll report it here.

Watch this space.


UPDATE – 16th May, 2016

Wow! So this is all happening very fast.

Today, Enterin Inc. has just enrolled their first patient in the RASMET study: a Phase 1/2a randomised, controlled, multi-center clinical study evaluating synthetic squalamine in people with PD. The study will enrol 50 patients over a 9-to-12-month period (Click here for the press release).

We’ll continue to watch this space… things appear to be moving very quick here!


The banner for today’s post was sourced from X-ray Mag