Parkinson’s disease (PD) is a complex condition with a variety of causes we don't yet fully understand, and while a small number of cases are associated with genetic mutations, the majority originate from a combination of factors. Understanding the underlying causes of PD is becoming an invaluable route to the discovery of new and promising treatments.

Several studies have suggested that people who are diabetic may be more likely to be diagnosed with Parkinson’s at some point in their lifetime. In a recent review, researchers explain the association between diabetes and Parkinson’s, and why certain anti-diabetic drugs may confer protection from PD, or even modify its course. Read the full paper here. 

Diabetes affects approx. 8% of the global population. It causes problems in blood sugar control, resulting in abnormally high levels throughout the body. The brain has no means of protecting itself from high glucose levels so neurons are exposed directly. Exposing nerve cells to higher than normal glucose levels may damage them by interacting with the protein a-synuclein (present in the neurons of the healthy brain and in the Parkinsonian brain this protein becomes abundant in a clumped and misfolded state). 

But what is the link to Parkinson’s? Why might people with diabetes be at greater risk of developing PD? The answer may be connected with the random, haphazard reactions that sugars and proteins undergo inside neurons - known as 'glycation'. This can produce up to 300 different medium and advanced end products (known as MGOs and AGEs respectively). Research in animal and human brain tissue has shown that free floating AGEs combine with a-synuclein causing it to form clumps which damage neurons.

Glycation and its toxic end products, AGEs, can be reduced by controlling blood sugar levels, but also by targeting MGOs, the intermediate products that go on to form AGEs, and breaking down AGEs directly. Anti-diabetic drugs such as exenatide (known as GLP-1's) have disease modifying effects and metformin has been shown to mop up excess MGOs. 

The role of GLP-1 drugs are of particular interest to CPT and we are keenly advancing research in this area: 

Read more of the Exenatide trial here:

https://www.cureparkinsons.org.uk/news/bydureonresults

Athauda, D., Wyse, R., Brundin, P., & Foltynie, T. (2017). Is Exenatide a Treatment for Parkinson's Disease? J Parkinsons Dis, 7(3), 451-458. doi:10.3233/JPD-171192

Read more about other GLP-1 Research with novel treatment MSDC-0160

https://www.cureparkinsons.org.uk/News/msdc0160-bydureon