https://medicalxpress.com/news/2019-11-inflammatory-bowel-disease-impact-parkinson.html
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Relatively new research findings indicating that the earliest stages of Parkinson's disease (PD) may occur in the gut have been gaining traction in recent years. In a review published in the Journal of Parkinson's Disease, Tomasz Brudek, Ph.D., evaluates evidence for the association between inflammatory bowel disease (IBD) and PD and proposes directions for future research.
"Parkinsonism is probably not just a brain disorder, but a group of diseases that may have their onset in the periphery, particularly in the gastrointestinal tract," explained Dr. Brudek, of the Research Laboratory for Stereology and Neuroscience, and Copenhagen Center for Translational Research, Copenhagen University Hospital, Bispebjerg, and Frederiksberg Hospital, Copenhagen, Denmark. "Taken together, all data, including human, animal, and microbiome studies, suggest quite strongly that individuals with an increased tendency for peripheral inflammation have a higher risk to acquire PD. Given the potentially critical role of gut pathology in the pathogenesis of PD, there is reason to suspect that IBD may impact PD risk."