Molecular Mechanisms of Polysaccharides in Regulating Immune Function and Treating Rheumatoid Arthritis Through Modulation of Gut Microbiota.

OBJECTIVE

To clarify the core mechanisms by which polysaccharides treat rheumatoid arthritis (RA) via gut microbiota modulation, and to systematically summarize their regulatory network and therapeutic potential.

Methods

This study adopted a systematic review approach to synthesize existing evidence on polysaccharides in RA, focusing on their structural features, interactions with the gut microbiota, and downstream effects on host immunity and metabolism.

RESULTS

Polysaccharides with specific structural features (e.g., plant-derived polysaccharides containing β-1,4 glycosidic bonds) selectively enhanced the abundance of gut probiotics (e.g., Bifidobacterium and Lactobacillus) by 15%-30%. They also promoted the production of short-chain fatty acids (SCFAs, such as acetate and propionate) through microbial degradation, increasing intestinal concentrations of these metabolites by more than 20%. These changes further regulated host metabolism and immune function, including restoring the balance between regulatory T cells (Treg) and T helper 17 cells (Th17), and inhibiting the nuclear factor-kappa B (NF-κB) signaling pathway to alleviate joint inflammation.

LIMITATIONS: Current research has critical clinical translation barriers: most evidence relies on in vitro experiments and animal models (e.g., collagen-induced arthritis (CIA) mice), while human clinical trials are restricted by small sample sizes and a lack of long-term follow-up data.

CONCLUSIONS

Targeted interactions between polysaccharides and the gut microbiota represent a crucial pathway for RA intervention. Future research should focus on optimizing polysaccharide structural modification technologies, conducting large-scale multicenter clinical trials, and exploring personalized therapeutic strategies to promote the clinical translation of polysaccharides in RA treatment.