Parkinson's Disease Linked To Gut Bacteria

For the first time, a new study highlights the link between gut bacteria and Parkinson's disease, one of the world's most common debilitating brain disorders.

A team of researchers at Caltech has found that changes in the type and number of microbes in a person's gut may help determine whether they will develop Parkinson's disease. Moreover, the researchers showed how changing the bacteria in the guts of mice affected the manifestation of Parkinson's disease symptoms.

Published in the journal Cell, the findings of the study could shed light on the development of new treatments for the disease. Thus, targeting the gut rather than the brain could someday help manage and treat the debilitating disease.

The researchers hope the new information gathered from the experiments could help develop new probiotics, more modern and sophisticated than those found on the market today.

Parkinson's disease affects about 1 million people and 1 percent of the population over 60 years old in the United States. The accumulation of abnormally shaped alpha-synuclein proteins in the neurons leads to the development of the disease.

This is because these proteins have toxic effects in the dopamine-releasing cells found in the area of the brain that controls movement. Patients suffering from Parkinson's disease experience symptoms like muscle stiffness, tremors, slowed movements and impaired gait.

Experiments On Mice

The scientists used genetically modified mice with a Parkinson's-like disease in three types of environment: normal, non-sterile or germ-free. They found that those raised in a germ-free environment showed lesser motor deficits and decreased the accumulation of misfolded protein aggregates in the brain regions responsible for controlling movement.

On the other hand, the mice with the complete microbiome had accumulations of the protein in the brain cells. Later, they began showing brain damage in the regions that one would expect for a Parkinson's patient, CNBC reports.

"Long-term, high-strength antibiotic use, like we utilized in this study, comes with significant risk to humans, such as defects in immune and metabolic function," Timothy Sampson of the California Institute of Technology said in a press release by Science Daily.

"Gut bacteria provide immense physiological benefit, and we do not yet have the data to know which particular species are problematic or beneficial in Parkinson's disease," he added.

Translating the ground breaking discovery from mice to humans will take many years. However, the discovery in a huge step in achieving the long-term goal of shedding light on the connection between gut bacteria and the brain.