基于肠道菌群和代谢组学研究牡蛎多糖改善小鼠2型糖尿病的作用机制OA

This study investigated the therapeutic mechanism of oyster polysaccharide(OPS)on type 2 diabetes mellitus(T2DM).A T2DM mouse model was established through high-fat diet combined with intraperitoneal injection of streptozotocin(STZ).The experimental mice were divided into six groups:normal control(NC),model control(MC),low-dose OPS(OPS-L),medium-dose OPS(OPS-M),high-dose OPS(OPS-H),and positive control(metformin,MET).Comprehensive evaluations were conducted,including blood glucose and lipid profiles,hepatic and renal histopathology,16S rDNA-based gut microbiota analysis,and untargeted fecal metabolomics.Compared to the MC group,the OPS-L and OPS-M groups exhibited significant reductions in fasting blood glucose(FBG),fasting serum insulin(FINS),and homeostatic model assessment of insulin resistance(HOMA-IR)(P<0.01,P<0.001),along with increased body weight(P<0.05).Serum levels of triglycerides(TG),total cholesterol(TC),and low-density lipoprotein cholesterol(LDL-C)were reduced to varying degrees,with alleviated hepatic and renal tissue damage.Notably,the OPS-M group demonstrated the most pronounced hypoglycemic effects.OPS treatment modulated gut microbiota composition in T2DM mice,restoring α-and β-diversity indices toward NC group levels.Serum metabolomics revealed alleviated metabolic pathways involving histidine metabolism,alpha-linolenic acid metabolism,and ketone body synthesis/degradation.Correlation analysis identified significant associations between differential bile acid metabolites and specific bacterial taxa,particularly g_Muribaculaceae and g_Rikenellaceae_RC9_gut_group.This study indicates OPS ameliorates T2DM in mice through mechanisms potentially linked to gut microbiota modulation,fecal metabolite regulation,and alterations in serum bile acid profiles.