Gut-brain axis dysfunction in Parkinson's disease: a meta-analysis of microbiome dysbiosis and intestinal barrier markers

Background

Parkinson's disease (PD) has traditionally been conceptualized as a neurodegenerative disorder centered within the central nervous system. However, growing evidence suggests that gastrointestinal dysfunction, intestinal permeability abnormalities, and gut microbiome dysbiosis may contribute to disease initiation and progression in a subset of patients. While several studies have characterized microbial alterations in PD, the integration of dysbiosis with intestinal barrier dysfunction and emerging phenotype-oriented models remains incompletely synthesized.