Abstract
In a recent Am J Physiol (GI and Liver Physiol) publication, Nieves, et. al. define the role of microbiota-derived indole metabolites in a mouse model harboring a defined microbiota. The authors observed that exogenous administration of the tryptophan metabolites indole propionic acid (IPA) to colitic mice significantly enhances intestinal barrier function. Further, the authors found that IPA independently stabilized components of the defined microbiota to enhance survival in the presence of established inflammation. This commentary summarizes these findings and discusses the implications of this work at a broader level.