Hormone produced during exercise protects brain cells in mice

Research published in the scientific journal of Proceedings of the National Academy of Sciences has found that irisin can slow and even stop Parkinson's-like symptoms in mice. 

Irisin is a hormone made by muscles during exercise in both mice and humans. Previous work has shown that boosting this hormone is beneficial in animal models of Alzheimer’s when it comes to memory. Results now show that it also holds promise in Parkinson’s. 

What did the researchers do? 

The researchers first found that irisin could prevent the build up of a troublesome protein called alpha-synuclein, often associated with Parkinson’s, when looking at cells grown in a dish. 

The team then used an injection to boost the levels of irisin in mice with high levels of alpha-synuclein in the brain, which are sometimes used to study how Parkinson’s develops. These mice appeared to move more easily than those who hadn’t received the injection.

Looking more closely at the brains of these mice, the researchers saw that there were fewer harmful clumps of alpha-synuclein because of the boost in irisin. They also found the mice lost fewer dopamine-producing cells compared to the mice who had a dummy injection.

The study even went on to show that irisin might be protecting dopamine-producing cells by boosting the cell’s recycling system, which is responsible for helping to rid cells of unwanted, old or harmful proteins. 

Researchers will use these results to continue to investigate irisin and its potential in Parkinson’s. 

Dr Katherine Fletcher, Research Communications Manager at Parkinson's UK, said:

"The results of this study are significant because, although we know that physical activity and exercise are beneficial for people with Parkinson's, it's currently unclear how this impacts the cells and processes in the brain that are contributing to symptoms of the condition. This study sheds some light on how a hormone produced during exercise might be acting to protect vital brain cells from dying in Parkinson's.

"Anything that shows promise in protecting brain cells in Parkinson’s offers hope, as currently there are no treatments that can slow or stop the condition. Something that is desperately needed for the 145,000 people diagnosed with Parkinson’s in the UK.

"However, it’s unclear from these results if exercise alone would generate enough irisin to have protective effects or if using other means to boost this hormone might be a more realistic therapeutic option in the future. The research has so far been done in a lab based setting and will need further development before paving the way for a future therapy that might be able to slow or stop the condition for people with Parkinson's."