Psyllium-derived, medium-molecular weight arabinoxylan enables modulation of the gut microbiota and metabolites in type 2 diabetic mice.

Patients with diabetics usually exhibit disordered glucose and lipid metabolism, as well as disrupted intestinal microecology. Dietary adjustment is essential for controlling diabetes. This study evaluated the ameliorative effects of psyllium-derived medium-molecular-weight arabinoxylan (MMW-AX) on glycolipid biochemical indicators, pathological symptoms, and intestinal microbial diversity in mice with Type 2 diabetes mellitus (T2DM). T2DM mice fed a high-sugar and high-fat (HSHF) diet combined with streptozotocin (STZ) exhibited severely impaired blood lipid levels, insulin function, liver tissue, and intestinal microbiota. Intervention with MMW-AX effectively alleviated glucose and lipid metabolism disorders and liver damage, with particularly significant effects in repairing lipid metabolism abnormalities. Furthermore, MMW-AX improved microbial diversity and short-chain fatty acid (SCFA) metabolism. Compared with the model group, MMW-AX significantly inhibited the relative abundance of Bacteroidetes and significantly increased the relative abundance of Bacillota, in a dose-dependent manner. Moreover, it altered the relative abundance of bacterial genera such as Lactobacillus, Blautia, Adlercreutzia, Ligilactobacillus, and Lachnospiraceae at the genus level. This study indicates that MMW-AX contributes to T2DM regulation by repairing pancreatic islet or liver function, and by modulating the composition of gut microflora and related metabolites. Overall, this study provides both a theoretical and practical basis for the development and functional evaluation of psyllium polysaccharide products for diabetes.