Gut power: Stomach bacteria may slow — And even reverse — Parkinson's disease

EDINBURGH, Scotland — Parkinson's disease, a progressive nervous system disorder that greatly affects movement, can have a detrimental impact on one's quality of life. While there are medications available that help control its symptoms, there is no known cure for the disease. However, researchers from the Universities of Edinburgh and Dundee in Scotland recently identified a potential game changer in the fight against Parkinson's. A common probiotic, or “good” bacteria, found in our stomachs that helps maintain digestive health appears to be able to slow, and even reverse, the accumulation of a protein known to be associated with Parkinson's.

The groundwork for these findings were put in place by prior research that had identified a connection between brain function and gut bacteria. Now, using a group of roundworms, this study has discovered that the probiotic called Bacillus subtilis is capable of stopping the formation of toxic clumps in the brain that impede the flow of dopamine. Dopamine, besides its other uses, is integral to coordinating movement.

Within the brains of Parkinson's patients, the protein known as alpha-synuclein builds up, forming these aforementioned toxic clumps. These clumps then cause the death of nerve cells that should be producing dopamine. It's the loss of these very cells that cause the trademark symptoms of Parkinson's, such as shaking or overall slowness of movement.

The research team used a genetically altered group of roundworms capable of producing the human version of clump-forming alpha-synuclein. These worms were fed a variety of different over-the-counter probiotics, in an effort to see if any of them influenced subsequent clump formation.

The results of the experiment revealed that Bacillus subtilis had a robust protective effect that prevented the buildup of the alpha-synuclein protein. The probiotic even was able to do away with some pre-existing clumps that had already formed within the worms. After being given Bacillus subtilis, the worms movements immediately improved.

“The results provide an opportunity to investigate how changing the bacteria that make up our gut microbiome affects Parkinson's. The next steps are to confirm these results in mice, followed by fast-tracked clinical trials since the probiotic we tested is already commercially available,” says Lead researcher Dr. Maria Doitsidou, of the Centre for Discovery Brain Sciences at the University of Edinburgh, in a release.

This piece of research is just the latest in a string of studies over the past few years indicating that the gut microbiome residing in each one our stomachs plays a critical role in brain function.

“Parkinson's is the fastest growing neurological condition in the world. Currently there is no treatment that can slow, reverse or protect someone from its progression but by funding projects like this, we're bringing forward the day when there will be,” comments Dr Beckie Port, Research Manager at Parkinson's UK. “Changes in the microorganisms in the gut are believed to play a role in the initiation of Parkinson's in some cases and are linked to certain symptoms, that's why there is ongoing research into gut health and probiotics.

“The results from this study are exciting as they show a link between bacteria in the gut and the protein at the heart of Parkinson's, alpha synuclein. Studies that identify bacteria that are beneficial in Parkinson's have the potential to not only improve symptoms but could even protect people from developing the condition in the first place,” she concludes.

The study is published in Cell Reports.