Figure 2.

The diet and gut microbiota perturb immune responses in IBD. Dietary constituents such as macronutrients and food additives have been shown to affect the gut microbiota in humans. Diet-induced alterations of the gut microbiota may exert diverse effects on gut mucosal immune responses and IBD-associated dysbiosis promotes gut inflammation in preclinical models, partly by loss of production of beneficial microbial metabolites, such as SCFAs and indole derivatives. In addition, the bloom of certain pathobionts may impair the epithelial barrier and stimulate a proinflammatory environment. AhR, arylhydrocarbon receptor; BA, bile acid; ER, endoplasmic reticulum; H2S, hydrogen sulfide; IBD, inflammatory bowel diseases; IL, interleukin; SCFA, short chain fatty acid.