An Insight into the Changing Scenario of Gut Microbiome during Type 2 Diabetes

Abstract

The gut microbiome consists of bacteria, protozoans, viruses, and archaea collectively called as gut microbiota. Gut microbiome (GM) modulates a variety of physiological responses ranging from immune and inflammatory responses, neuronal signalling, gut barrier integrity and mobility, synthesis of vitamins, steroid hormones, neurotransmitters to metabolism of branched-chain aromatic amino acids, bile salts, and drugs. Type 2 diabetes mellitus (T2D) is a highly prevalent metabolic disorder that is featured by imbalance in blood glucose level, altered lipid profile, and their deleterious consequences. GM dysbiosis a major factor behind the incidence and progression of insulin resistance and is responsible for altering of intestinal barrier functions, host metabolic, and signaling pathways. The GM of type 2 diabetes (T2DM) patients is characterized by reduced levels of Firmicutes and Clostridia and an increased ratio of Bacteroidetes:Firmicutes. Endotoxemia stimulates a low-grade inflammatory response, which is known to trigger T2DM. Xenobiotics including dietary components, antibiotics, and nonsteroidal antiinflammatory drugs strongly affect the gut microbial composition and can promote dysbiosis. However, the exact mechanisms behind the dynamics of gut microbes and their impact on host metabolism are yet to be deciphered. Interventions that can restore equilibrium in the GM have beneficial effects and can improve glycemic control.