G.P.N.M.B

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There is a critical need for good biomarkers in neurodegenerative research.

A biomarker is an objective indicator of a medical state that can be assessed from outside a patient, and can be measured accurately and reproducibly. It could come in the form of a medical imaging application or a biological sample (such as a blood test).

Recent research points towards a particular protein (referred to as GPNMB) that could be a potential biomarker for a specific subtype of Parkinson’s.

In today’s post, we will review some of the research on this topic and consider how a biomarker could potentially be used in Parkinson’s research.

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Source: TED

Back in 2016, some researchers reported something interesting.

They had been investigating cells collected from people with a condition called Gaucher disease (Pronounced: ‘Go-Shay’; don’t ask – we’ll discuss what it is in a moment, just let me get the intro out of the way). Specifically, the scientists were seeking potential biomarkers for Gaucher disease… and they might have found one.

Here is their report:

Title: Elevation of glycoprotein nonmetastatic melanoma protein B in type 1 Gaucher disease patients and mouse models.
Authors: Kramer G, Wegdam W, Donker-Koopman W, Ottenhoff R, Gaspar P, Verhoek M, Nelson J, Gabriel T, Kallemeijn W, Boot RG, Laman JD, Vissers JP, Cox T, Pavlova E, Moran MT, Aerts JM, van Eijk M.
Journal: FEBS Open Bio. 2016 Jul 30;6(9):902-13.
PMID: 27642553                 (This report is OPEN ACCESS if you would like to read it)

In the study, the researchers collected cells from the spleen of an individual with Gaucher disease and looked for proteins in the cells that were higher than normal.

They found glycoprotein non-metastatic melanoma protein B (GPNMB, also known as osteoactivin) was ridiculously high. Off the charts high. They then compared GPNMB levels in blood samples collected from 59 people with Gaucher disease and 20 healthy controls. As you can see in the graph below, GPNMB levels were on average 25‐fold higher in all of the 59 people with Gaucher disease (Note: the Y axis is logarithmic):

Source: PMC

Interestingly, when the individuals with Gaucher disease started the standard treatment for the condition, the levels of GPNMB collectively dropped:

Source: PMC

And this result has been independently validated (Click here to read that report). The second study used a larger cohort of individuals with Gaucher disease (155 patients) and they found a >15-fold elevation of GPNMB in the blood of this group (compared to controls). And again these high levels were reduced when the Gaucher group started treatment:

Source: PMC

A third study found that GPNMB levels in the brains of a mouse model of Gaucher disease correlated with disease severity in the mice, and also reported elevated GPNMB levels in brain samples from patients with Gaucher disease.

All of the research groups concluded that their data supports the potential utility of GPNMB as a biomarker of Gaucher disease.

Great! But what is Gaucher disease and why is this on a website for Parkinson’s research?

Continue reading “G.P.N.M.B”

Making a strong case for GCase

Novel therapies are increasing being developed to focus on specific subtypes of Parkinson’s. The hope is that if they work on one type of Parkinson’s, then maybe they will also work on others.

Many of these new experimental treatments are focused on specific genetic subtypes of the condition, which involve having a specific genetic variation that increases one’s risk of developing Parkinson’s.

Increasing amounts of data, however, are accumulating that some of the biological pathways affected by these genetic variations, are also dysfunctional in people with sporadic (or idiopathic) Parkinson’s – where a genetic variation can not explain the abnormality.

In today’s post, we will review some new research that reports reductions in a specific Parkinson’s-associated biological pathway, and discuss what it could mean for future treatment of the Parkinson’s.


Source: Medium

I was recently at a conference on Parkinson’s research where a prominent scientist reminded the audience that just because a person with Parkinson’s carries certain genetic risk factor (an error in a region of their DNA that increases their risk of developing Parkinson’s), does not mean that their Parkinson’s is attributable that genetic variation. Indeed, lots of people in the general population carry Parkinson’s associated genetic risk factors, but never go on to develop the condition.

And this is a really important idea for the Parkinson’s community to understand: Most of the genetics of Parkinson’s deals with ‘association’, not with ‘causation’.

But that begs the question ‘if we do not know that these errors in our DNA are causing Parkinson’s, then why should we be trying to develop therapies based on their biology?’

It is a fair question (it is also a very deep and probing question to start a post off with!).

The genetics of Parkinson’s has been extremely instructive in providing us with insights into the potential underlying biology of the condition. We have learnt a great deal about what many of the biological processess thatare associated with these genetic risk factors, and (yes) various experimental therapies have been developed to target them.

These novel treatments are clinically tested in the hope that they will have beneficial effects not just on individuals carrying certain genetic risk factors, but also on the wider Parkinson’s community.

And recently, there has been increasing evidence supporting this possibility. Some of the biological pathways associated with these genetic mutations appear to also be abnormal in people with Parkinson’s who do not carry the genetic variation.

What do you mean?

Continue reading “Making a strong case for GCase”

When GCase is away, the GSLs will play

 

 

New research published in the last week provides further experimental support for numerous clinical trials currently being conducted, including one by the biotech company Sanofi Genzyme.

Researchers have demonstrated that tiny proteins which usually reside on the outer wall of cells could be playing an important role in the protein clustering (or aggregation) that characterises Parkinson’s

In today’s post we will look at this new research and discuss what it could mean for the on going clinical trials for Parkinson’s. 


Source: Stevedalepetworld

The proverb ‘When the cat is away, the mice will play’ has Latin origins.

Dum felis dormit, mus gaudet et exsi litantro (or ‘When the cat falls asleep, the mouse rejoices and leaps from the hole’)

It was also used in the early fourteenth century by the French: Ou chat na rat regne (‘Where there is no cat, the rat is king’).

And then Will Shakespeare used it in Henry the Fifth(1599), Act I, Scene II:

Westmoreland, speaking with King Henry V, Gloucester, Bedford, Exeter and Warwick
“But there’s a saying very old and true,
‘If that you will France win,
Then with Scotland first begin:’
For once the eagle England being in prey,
To her unguarded nest the weasel Scot
Comes sneaking and so sucks her princely eggs,
Playing the mouse in absence of the cat,
To tear and havoc more than she can eat”

The phrase first appears in its modern form in the United States in the literary and political magazine The Port folio in 1802 (2; 323):

Interesting. But what does any of this have to do with Parkinson’s?

Continue reading “When GCase is away, the GSLs will play”