Larch Arabinogalactan Alleviates Colitis by Modulating Gut Microbiota and Promoting <i>Bacteroides thetaiotaomicron</i>
Shanshan Zhang, Yonggan Sun, Xinyu Bian, Fangwei Liu, Shaoping Nie
Abstract
High Resolution Image Download MS PowerPoint Slide Inflammatory bowel disease (IBD) is linked to gut microbiota dysbiosis, and modulating microbiota through diet is a promising IBD management strategy. Larch arabinogalactan (AG) is a natural polysaccharide with potential prebiotic effects; however, its regulatory effects on gut microbiota and the underlying anti-inflammatory mechanisms remain unclear. Here, we demonstrated that AG improves gut homeostasis in dextran sulfate sodium-induced colitis mice, with effects depend on the gut microbiota. Further analysis revealed that AG notably enriched the Bacteroides, particularly Bacteroides thetaiotaomicron . Specifically, B. thetaiotaomicron exhibited anti-inflammatory activity, producing propionate and upregulating colonic G-protein-coupled receptor 41 (GPR41) expression, effects also observed in AG-treated mice. Collectively, our findings reveal the targeted regulatory effects of AG on gut microbiota and demonstrate that the B. thetaiotaomicron -propionate-GPR41 axis contributes to the amelioration of colitis by AG. These results provide new scientific evidence for the application of AG in health foods and offer novel insights for microbiota-targeted nutritional intervention.