Intestinal barrier restoration in UC: dietary protein/peptide mediate microbiota-Trp-AhR axis and food processing implications.

The incidence and prevalence of UC are increasing due to changes in diet and lifestyle. An increasing number of studies have suggested that the intestinal barrier is a key factor in the occurrence and development of UC, which is closely related to gut microbiota, the tryptophan (Trp) metabolism pathway, and aryl hydrocarbon receptor (AhR) activation. This review summarizes the current knowledge on the impact of the intestinal barrier on UC. The relationship between gut microbiota and the intestinal barrier in UC is also examined. Importantly, this review highlights the advances in the understanding of microbiota-mediated the Trp-AhR pathway in repairing the intestinal barrier. Furthermore, the potential influence of dietary proteins/peptides targeting gut microbiota to regulate the Trp-AhR pathway and alleviate intestinal barrier dysfunction in UC, and the effect of food processing on dietary proteins/peptides to influence gut microbiota and Trp metabolism are discussed. Dietary proteins/peptides could alleviate intestinal barrier impairment in UC by modulating the gut microbiota-mediated Trp-AhR pathway.