Bacteria Living in the Gut Could be Responsible for Parkinson's Disease

A new study from the California Institute of Technology revealed a potential biological connection between gut microbiome and Parkinson's disease, suggesting that the incurable neurodegenerative disease may have originated in the gut and not only in the brain as had been previously thought.

The study, published in the journal Cell, showed that mice given with bacteria from the gut of Parkinson's patients have experienced more symptoms than those who are given with bacteria from healthy people.

"This research reveals that a neurodegenerative disease may have its origins in the gut and not only in the brain as had been previously thought," explained Dr. Sarkis Mazmanian, a researchers at Cal Tech and lead author of the study, in a report from BBC. "The discovery that changes in the microbiome may be involved in Parkinson's disease is a paradigm shift and opens entirely new possibilities for treating patients."

For the study, the researchers first genetically modified mouse models to make them develop Parkinson's. The researchers were able to induced Parkinson's to their mouse models by making them produce high levels of alpha-synuclein, which is associated with the damage in the brain of Parkinson's patients. Fecal samples were then taken from Parkinson's patients and healthy persons. These samples were injected into the mouse models.

The researchers observed that the mice who received bacteria from Parkinson's patients developed more symptoms of the neurodegenerative disease compared to those injected with bacteria from healthy people. The researchers noted that the mice that they used in the study were genetically identical, making the bacteria injected into them the only difference.

Bacteria in the gut were known to break down fiber into short-chain fatty acids. The researchers believe that during the breakdown process, these bacteria release chemicals that could trigger over-activity in the immune cells of the brain, leading to the damage.

More studies are needed to establish a perfect gut-brain connection in Parkinson's. However, the researchers noted that their findings can already revolutionize possible treatments for Parkinson's including the possibility of using probiotics as a new therapy for the disease.