Indole dysbiosis and mucosal inflammation
Ji Yeon Kim, Ian M. Cartwright, Sean P. Colgan
Abstract
The inflammatory bowel diseases (IBD) coincide with shifts in the composition of the microbiota. Since the gastrointestinal (GI) epithelium is anatomically positioned to provide a selective barrier between the microbiota and host lamina propria, this barrier is essential for intestinal homeostasis. Decades-old studies have appreciated that byproducts of the microbiota provide an essential communication network to the host. More recent work has identified microbial-derived metabolites that support multiple functions within the GI mucosa. One such family of metabolites are the indoles, tryptophan-derived molecules that signal within the microbiota and importantly, provide anti-inflammatory properties within the host mucosa. Here, we review the topic of indole production and signaling in the healthy and diseased mucosa.