Synergistic Protective Effects of Different Dietary Supplements Against Type 2 Diabetes via Regulating Gut Microbiota

Diabetes mellitus is a global health problem, and its prevalence continues to increase. Dietary supplements, including probiotics, prebiotics, and plant extracts, have been shown to alleviate diabetes. In this study, the synergistic effects of two types of dietary supplements were investigated in a mouse model of type 2 diabetes mellitus (T2DM). Sixty mice were divided into the following six groups: control, model (induced by a high-fat diet and intraperitoneal injection of streptozotocin), drug (metformin), probiotic (Lactobacillus spp.), formula A (probiotics, plant extracts, and soybean peptide), and formula B (probiotics, prebiotics, and soybean peptide). All three dietary interventions (probiotic, formula A, and formula B groups) significantly reduced the blood glucose level and oral glucose tolerance level and effectively improved some biochemical parameters (e.g., chronic inflammation, oxidative stress, and blood lipid level) and regulated gut microbiota. Notably, formula B exhibited a better ability on reducing the blood glucose level, regulating the gut microbiota, and increasing the short-chain fatty acid levels compared with the probiotics alone and formula A. Thus, formula B may exert synergistic protective effects against T2DM through a mechanism involving probiotics and prebiotics of gut microbiota regulation. This study provides a theoretical basis for the application of probiotic dietary supplements to the treatment of T2DM.