Gut microbiota in pathogenesis and therapeutic potentials in rheumatoid arthritis.

This review comprehensively explores the emerging roles of gut microbiota in the pathogenesis and therapeutic implications of rheumatoid arthritis (RA). Clinically, RA is a challenging autoimmune disease due to unclear pathology and limitations of conventional therapies. Recent studies highlight that gut dysbiosis - characterized by reduced microbial diversity, enrichment of proinflammatory taxa, and depletion of anti-inflammatory species - is an important contributor to RA. Mechanistically, gut microbiota dysregulation drives RA through molecular mimicry, metabolite-mediated inflammation, and immune cell migration. Therapeutic strategies targeting the gut-joint axis, including probiotics, high-fiber diets, Mediterranean dietary patterns, and fecal microbiota transplantation (FMT), demonstrate promise in restoring microbial homeostasis, enhancing intestinal barrier integrity, and suppressing proinflammatory cytokines. While preclinical and clinical studies underscore the potential of microbiota-based interventions, challenges such as standardization of FMT protocols and long-term safety require further investigation.