Metabolism of alimentary compounds by the intestinal microbiota and consequences for gut health

Abstract

The intestinal microbiota in the mammalian large intestine metabolizes numerous alimentary compounds that are not digested and absorbed in the small intestine. By doing so, microbiota produces metabolites that accumulate in the luminal fluid. Several bacterial metabolites have been shown to be involved in communication between microbes and to act on the colonic epithelial cell metabolism and physiology. In fact, effects of bacterial metabolites on energy metabolism in colonic epithelial cells, water and electrolyte movements across the colonic epithelium, and epithelial renewal and barrier function have been reported. In this review, the consequences of such interkingdom metabolic interactions are summarized by presenting typical examples of bacterial metabolites that are known to affect communication between intestinal microbes and/or between microbes and the intestinal epithelial cells. Current studies indicate that the bacterial metabolites derived from alimentary compounds affect the colonic epithelial cells either positively or negatively. These findings pave the way for further experimental and clinical studies aiming at establishing what can be done in terms of alimentary intervention to optimize host-microbe communication for beneficial effects on gut health.