![\"Parkinson\u2019s](\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2025\/09\/parkinsons-and-oral-bacteria--1024x576.jpg\")
Parkinson\u2019s disease is a common brain disorder marked by tremors, muscle stiffness and slowed movement. (iStock)<\/p>\nParkinson\u2019s disease is a common brain disorder marked by tremors, muscle stiffness and slowed movement. (iStock)<\/p>\n
A bacterium best known for causing tooth decay has been linked to Parkinson\u2019s disease, in what researchers call the first study to show a direct microbial pathway driving the condition.<\/p>\n
The study, published this month in Nature Communications<\/a>, was led by researchers in South Korea at POSTECH and Sungkyunkwan University, with collaborators from Seoul National University. It found that Streptococcus mutans \u2014 typically found in the mouth \u2014 was present in the gut microbiome of people with Parkinson\u2019s disease and appeared to play a central role.<\/p>\n The team analyzed stool samples from nearly 500 patients with Parkinson\u2019s and 234 healthy controls, creating a high-resolution profile of the gut microbiome. <\/p>\n They discovered that S. mutans produces an enzyme called UrdA, which generates a compound known as imidazole propionate. That metabolite, the authors showed, can travel to the brain and damage dopamine-producing neurons \u2014 a hallmark of Parkinson\u2019s.<\/a><\/p>\n When researchers introduced S. mutans or the metabolite into mice, the animals developed motor problems and brain changes resembling those seen in Parkinson\u2019s disease.<\/p>\n The findings suggest, for the first time, a direct \u201cgut\u2013brain\u201d microbial mechanism for the neurodegenerative disorder, and raise questions about whether oral health could influence neurological disease risk.<\/p>\n Other recent research<\/p>\n Just months earlier, on June 9, a separate study led by King\u2019s College London reported that mouth and gut bacteria were linked to brain changes in Parkinson\u2019s<\/a>, particularly in relation to cognitive decline. That study, however, was observational and focused on associations seen in MRI scans \u2014 without identifying a specific microbial pathway.<\/p>\n Together, the two studies highlight a growing recognition of the oral\u2013gut\u2013brain axis in Parkinson\u2019s disease. <\/p>\n