Hypoglycemic Effect of Ginsenoside Rg5 Mediated Partly by Modulating Gut Microbiota Dysbiosis in Diabetic db/db Mice

In this study, we aimed to investigate the influence of ginsenoside Rg5 (Rg5) on gut microbiota in diabetic db/db mice. Our data indicated that Rg5 not only improved the symptoms of hyperglycemia, repaired intestinal barrier function, and relieved metabolic endotoxemia-related inflammation but also reversed gut microbiota dysbiosis in the colon with significantly decreased Firmicutes/Bacteroidetes ratios. More importantly, the effects of Rg5 were further confirmed by partial changes in the gut microbiota induced by broad-spectrum antibiotics. These findings indicated that Rg5 dramatically decreased the abundance of Firmicutes and Verrucomicrobia at the phylum level and increased the abundance of Bacteroidetes and Proteobacteria in diabetic db/db mice. Altogether, our findings, for the first time, demonstrate that Rg5 may be used as a beneficial probiotic agent that reverses gut microbiota dysbiosis and diabetes-associated metabolic disorders in the context of type 2 diabetes mellitus.