Association Between Blood-Brain Barrier Disruption and Gut Microbiota Dysbiosis in Parkinson's Disease.

Parkinson's disease (PD) is a chronic neurodegenerative disorder primarily characterized by motor dysfunction. It is the second most prevalent neurodegenerative disorder after Alzheimer's disease. Its pathological manifestations include typical motor symptoms associated with Lewy bodies and loss of nigrostriatal dopaminergic neurons. Emerging evidence indicates that blood-brain barrier (BBB) dysfunction contributes to the onset and progression of PD. The BBB is essential for maintaining central nervous system (CNS) homeostasis by restricting the entry of circulating components and exogenous substances into the brain. In PD, disruption of BBB integrity facilitates the infiltration of circulating neurotoxins, macromolecules, and microorganisms, thereby triggering neuroinflammatory and immune responses. Furthermore, gut microbiota dysbiosis significantly impacts the integrity and function of the BBB via inflammatory mediators and metabolites, thus promoting PD progression. This study summarizes the associations between the BBB and gut microbiota with the onset and progression of PD and investigates the potential of enhancing BBB integrity and optimizing the gut microbiota as a theoretical foundation for developing novel therapeutic approaches for PD. Clinical trial number: not applicable.