Impact of Gut Microbiota on Host Glycemic Control

Abstract

Given that obesity and associated disorder type II diabetes mellitus have reached epidemic proportions worldwide, the development of efficient prevention and therapeutic interventions is a global public health interest. There is now a large body of evidence suggesting that the micro-organisms colonizing the human gut, known as gut microbiota, play a central role in human physiology and metabolism. Understanding how gut microbiota affects and regulates key metabolic functions such as glucose regulation and insulin resistance is an important health issue. The present review summarizes recent advances in our understanding of how gut bacterial species interfere with host metabolic phenotype. We will examine key biological molecular mechanisms underlying the impact of gut microbiota on host glycemic control including: incretin secretion, short-chain fatty acid production, bile acid metabolism, and adipose tissue regulation. We will highlight how prebiotic/probiotic interventions affect these bacterial processes and are now considered as promising approaches to treat obese and diabetic patients.

Keywords: diabetes; glucose metabolism; microbiota; obesity; probiotics.

Figure 1

Schematic view of key mechanisms linking the gut microbiota with host glycemic regulation. These mechanisms include (1) increase of incretin secretion either through direct induction of GLP-1 production or via an increase of the number/differentiation of enteroendocrine cells; (2) bacterial production of SCFA with beneficial impacts on intestinal gluconeogenesis, gut wall integrity, incretin secretion, and pancreatic functions; (3) bacterial metabolism of bile acids contributing to bile acid pool diversity and inducing local and peripheral signaling effects including via FGF19 production in the gut; (4) adipose tissue regulation mainly through modulation of LPS-mediated inflammation and induction of white adipose tissue browning.