Evaluation of interleukin-6 and its soluble receptor components sIL-6R and sgp130 as markers of inflammation in inflammatory bowel diseases.

Purpose: Interleukin-6 (IL-6) production and signalling are increased in the inflamed mucosa in inflammatory bowel diseases (IBD). As published serum levels of IL-6 and its soluble receptors sIL-6R and sgp130 in IBD are from small cohorts and partly contradictory, we systematically evaluated IL-6, sIL-6R and sgp130 levels as markers of disease activity in Crohn's disease (CD) and ulcerative colitis (UC).

Methods: Consecutive adult outpatients with confirmed CD or UC were included, and their disease activity and medication were monitored.

Increased Tryptophan Metabolism Is Associated With Activity of Inflammatory Bowel Diseases.

Background & Aims: Administration 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 diseases (IBD), and study their association with clinical and serologic features.