Structural Characterization of a Branched Polysaccharide Isolated from <i>Thesium chinense</i> Turcz. and Its Ameliorative Effects on Ulcerative Colitis
G. Hu, Taili Shao, Jiapeng Wang, Haoyu Zhang, Xiaolong Shang, Chunyan Liu, Jianping Wu, Qiuyue Lv, Yuyan Zhou, Lingwu Chen, Jun Han, Guodong Wang
Abstract
Ulcerative colitis (UC) is a chronic, complex inflammatory condition with a high global prevalence. Thesium chinense Turcz. is renowned for its antibacterial and anti-inflammatory properties. In this study, a novel branched polysaccharide (TP1) was isolated from Thesium chinense Turcz., primarily composed of fructose, glucose, and galactose with a molecular weight of 5377 Da. Its backbone includes →1)-β-D-Fru f -(2→, →1,6)-β-D-Fru f -(2→, →4)-α-D-Glc p -(1→, and →3,6)-β-D-Gal p -(1→ residues, and the side chain is Fru f -(2→6)-β-D-Fru f -(2→ linked to the O-6 of the →1,6)-β-D-Fru f -(2→ residue, while β-D-Gal p -(1→ linked to the O-6 of the →3,6)-β-D-Gal p -(1→ residue. In DSS-induced UC mice, TP1 significantly ameliorated weight loss, colon shortening, and the intestinal barrier damage. Mechanistically, TP1 reestablished the gut microbiota, increased SCFAs concentrations, activated GPR41/43 receptors, and downregulated proteins expression in the IL-17/NF-κB/JAK2/STAT3 signaling axis. TP1 maintained Th17/Treg homeostasis may through the SCFAs-mediated GPR41/43 pathway and IL-17/NF-κB/JAK2/STAT3 pathway, thereby inhibiting intestinal inflammation to alleviate UC. This study provides new insights into therapeutic strategies for UC.