Based on the "gut microbiota-barrier-immunity" axis to explore the mechanism of action of traditional Chinese medicine polysaccharides in the treatment of inflammatory bowel disease and structure-activity relationship: A review.

Inflammatory bowel disease (IBD) is a chronic inflammatory disorder driven by genetic susceptibility, immune dysregulation, impaired intestinal barrier function and gut microbiota dysbiosis. Current immunosuppressive therapies are limited by significant side effects, high recurrence rates, and primary non-response in some patients, highlighting the urgent need for novel therapeutic strategies. Traditional Chinese medicine polysaccharides (TCMPs), as natural bioactive macromolecules with inherent multi-target regulatory properties, exhibit unique anti-IBD therapeutic potential. This review systematically elucidates the structure-activity relationships of TCMPs from six dimensions, including molecular weight, monosaccharide composition, glycosidic bonds, monosaccharide linkage positions, advanced structure, and chemical modification. It further elaborates their therapeutic mechanisms targeting the "gut microbiota-barrier-immunity" axis, and analyzes key clinical translation challenges. It also proposes future research strategies integrating nanotechnology, multi-omics, and targeted delivery systems to advance IBD drug development. This review provides a comprehensive theoretical foundation for the rational design and clinical translation of polysaccharide-based IBD therapeutics.