Kerala study finds gut‑microbe imbalance linked to Parkinson’s disease severity

A Kerala‑based study shows that the gut bacteria of people with Parkinson’s disease differ markedly from those of healthy individuals. Researchers from Cochin University of Science and Technology and the medical institute SCTIMST in Thiruvananthapuram conducted the work and published the results in npj Parkinson's Disease. The investigation enrolled 65 patients treated at SCTIMST’s Comprehensive Care Centre for Movement Disorders and 65 control participants, mostly the patients’ spouses, to match diet and living conditions. Stool samples were examined using metagenomic 16S rRNA gene amplicon sequencing, which identifies bacterial species and predicts their functions. The analysis revealed a rise in bacteria that are often linked to inflammation and a drop in microbes that generate short‑chain fatty acids, compounds that keep the intestinal wall healthy and modulate the immune system. The researchers say this shift may weaken the gut barrier, allowing inflammatory signals to reach the brain. Baby Chakrapani P. S., a scientist and director of the Centre for Neuroscience at CUSAT, noted that the bacterial differences correlated strongly with how severe the disease was and with other clinical signs. He added that the microbes could influence Parkinson’s progression by affecting chemicals such as dopamine, glutamate and GABA, which are crucial for brain function. The study received funding from the Indian Council of Medical Research and was led by research associate Aneesa P. A., under the supervision of Chakrapani and Dr Syam Krishnan of SCTIMST. Variations in diet, age, sex, lifestyle and genetics likely explain why earlier studies in other populations have reported mixed results. This is the first Indian project to combine gut‑microbiome composition with its functional impact on Parkinson’s disease, paving the way for simple early‑diagnosis tests and treatments aimed at restoring gut health.

Context

Gut microbes are known to affect many aspects of health, including brain function, and imbalances have been reported in several neurological conditions. The findings suggest that monitoring and adjusting the gut microbiome could become a useful strategy for detecting and managing Parkinson’s disease early.