A new study in humans appears to confirm what has been shown in animal studies – that a class of drug used to treat diabetes may reduce the risk of developing Parkinson’s disease.

Share on Pinterest Study finds diabetes patients taking glitazone pills were less likely to develop Parkinson’s disease than patients receiving other diabetes treatments.

Published in PLOS Medicine, the study shows diabetes patients taking glitazone prescription drugs were almost a third less likely to develop Parkinson’s disease than patients who were on other diabetes treatments and who had never taken that class of drug.

Estimates suggest around 1 in 500 people are affected by Parkinson’s disease. To date, there are no effective treatments that directly tackle the disease, which kills nerve cells that produce dopamine – a brain chemical that is essential for conveying messages to muscles that control movement.

Lab and animal studies have shown that glitazones may prevent loss of nerve cells.

The new study – led by the London School of Hygiene & Tropical Medicine in the UK – is the first to investigate glitazone use and incidence of Parkinson’s disease in humans.

First author Dr. Ruth Brauer, who worked on the study while at the School and is now at King’s College London, says:

“Although our study only looked at people with diabetes, we believe it’s likely that the protective effect of glitazones may also be seen in people without diabetes.”

The study suggests the reduced risk of developing Parkinson’s only lasts while patients keep taking glitazones – the results showed no lasting benefit for patients who used to take them and then switched to other drugs.

Glitazones treat diabetes by activating a receptor to reduce insulin resistance. The receptor is called peroxisome proliferation-activated gamma (PPARɣ). However, the receptor also has other functions, many of which have not been studied extensively in humans. A receptor is a protein embedded in the cell wall that acts as a gatekeeper allowing only certain signals to enter.