Yam Polysaccharide Ameliorates High-Fat and Fructose Diet-Induced Gestational Diabetes Mellitus in Mice via Gut Microbiota Remodeling

Background: Yam Polysaccharide (YP) is a major bioactive component extracted from the common yam rhizome and has been shown to have an antidiabetic effect. Previous research has demonstrated the association between gut microbiota (GM) and gestational diabetes mellitus (GDM); however, whether GM is essential for mediating the antidiabetic effects of YP in GDM remains unclear. Method: A high-fat and fructose diet (HFD) was administered to mice before and after pregnancy to induce GDM. An oral glucose tolerance test (OGTT) was performed, and the homeostatic model assessment of insulin resistance (HOMA-IR) was calculated to evaluate glucose metabolism. The GM composition was analyzed using 16S rRNA sequencing. Results: During pregnancy, mice fed an HFD exhibited significant weight gain accompanied by impaired glucose tolerance. These metabolic disturbances were alleviated by YP treatment. Furthermore, consuming an HFD induced marked alterations in GM diversity compared to the control group, characterized by increased abundance of Alloprevotella and decreased abundance of the Lachnospiraceae NK4A136 group. Importantly, YP administration reversed these HFD-induced microbial changes. Conclusions: These findings suggest that modulation of the GM is one mechanism underlying the antidiabetic effects of YP in GDM.