Increased Tryptophan Metabolism Is Associated With Activity of Inflammatory Bowel Diseases

Background & AimsAdministration of tryptophan and some of its metabolites reduces the severity of colitis in mice, whereas removing tryptophan from the diet increases susceptibility to colitis. Transfer of the intestinal microbiome transfers the colitogenic phenotype from tryptophan starved animals to normally nourished mice. We aimed to systematically evaluate serum levels of tryptophan and its metabolites in patients with inflammatory bowel...