Synucleinopathy begets channelopathy?

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Alpha synuclein is a protein that is closely associated with Parkinson’s. It was the first gene to be associated with increased risk of developing Parkinson’s, and the alpha synuclein protein was found to be present in Lewy bodies – a characteristic feature of the Parkinson’s brain.

As a result of this association, researcher have used high levels of this protein to model Parkinson’s in cell culture and animal experiments. 

Recently, scientists have reported that high levels of alpha synuclein can cause shrinkage of motorneurons, resulting in a reduction of gut motility in mice – potentially connecting multiple features of Parkinson’s in one study.

In today’s post, we will review the results of this new study and consider what could happen next.

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Channelopathy conditions. Source: Frontiers

A reader recently emailed me to ask if Parkinson’s is a channelopathy?

It’s a good question.

What is a channelopathy?

Channelopathies are conditions caused by disruption of the function of proteins involved in ion channels or the proteins that regulate them. These diseases can be either congenital (present from birth, often resulting from a genetic mutation) or acquired (often resulting from an insult such as autoimmune attack or toxin on a particular type of ion channel – click here to read a good review on this topic).

Hang on a second, what are ion channels?

Ion channels are protein structures in membranes that allow certain elements to pass through them into (or out of) the interior of a cell.

Source: Biologydictionary

These conduits play critical roles in many processes of normal cellular life – from passing signals between cells to general cellular well being (homeostasis). Many of these channels are very selective in what they allow to pass (for example, there are calcium channels and sodium channels which only allow calcium and sodium to pass, respectively).

When components of a channel are disrupted (resulting in dysfunctional activity in that channel), it can have serious implications for cells and the organisms that they inhabit.

Can you give an example of a disease that is a channelopathy?

Spinocerebellar ataxia type 6 (or SCA6) can be used as an example of a channelopathy.

Spinocerebellar ataxia are a collection of rare, genetic condition that is characterized by slowly progressive cerebellar ataxia (a lack of muscle coordination that can make speech and movement difficult) and nystagmus (involuntary, uncontrollable eye movements).

This video explains what spinocerebellar ataxia are:

SCA6 is a late onset form of spinocerebellar ataxia (typically starting after 65 years of age) – many people with SCA6 can be misdiagnosed with ALS or Parkinson’s. SCA6 is caused by mutations in CACNA1A, a gene that provides the instructions for making one part (the alpha-1 subunit) of a calcium channel called CaV2.1.

Very interesting. But how does this relate to Parkinson’s?

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