Gut Microbiota: Implications in Pathogenesis and Potential Therapeutic Target in Primary Biliary Cholangitis.

Primary biliary cholangitis (PBC) is a chronic progressive autoimmune disorder characterized by small non-purulent intrahepatic bile duct destruction (ductopenia) and cholestasis. While the etiology of PBC remains unclear, it is believed to involve genetic-environmental interactions. Emerging evidence highlights gut microbiota dysbiosis in PBC patients, with increased symbiotic bacteria and decreased pathogenic bacteria. Microbial alterations potentially influence disease pathogenesis through multiple mechanisms, including immune dysregulation, intestinal barrier damage, BA metabolic dysregulation, and cholestasis. These findings suggest that the gut microbiota can serve not only as a non-invasive biomarker for diagnosis and prognosis evaluation but also as a therapeutic target for the disease. In this review, we summarize changes in PBC patients' gut microbiota, explain how these changes affect disease occurrence and development, and discuss treatment methods with potential clinical value that intervene in gut microbiota.