Facing a new challenge: the adverse effects of antibiotics on gut microbiota and host immunity

Abstract

[1] These microbial communities reside with varied density in different segments of the gut and play a crucial role in many aspects of physiological processes, including facilitating food digestion and energy utilization, synthesizing vitamins and essential amino acids, promoting the development of the immune system, maintaining the integrity of the gut mucosal barrier, and protecting against enterogenous pathogens. Butyrate-producing anaerobes cannot directly utilize fructooligosaccharides and starch but can utilize lactate and acetate as growth substrates. [...]B. adolescentis can facilitate the proliferation and expansion of butyrate-producing species in vivo by cross-feeding. Deconjugated bile acids can be further used by bacteria or reabsorbed by the liver for bile acid enterohepatic circulation. Short-chain fatty acids (SCFAs), produced by bacteria in the large intestine through fermentation of fibers, have broad effects on enterocytes, including maintenance of epithelial integrity, regulation of Treg differentiation and accumulation, and modulation of inflammatory and immune responses.