Oral tryptophan activates duodenal aryl hydrocarbon receptor in healthy subjects: a crossover randomized controlled trial

• Published in: American journal of physiology: Gastrointestinal and liver physiology Vol. 326; no. 6; pp. G687 - G696
• Main Authors: Rueda, Gaston H., Causada-Calo, Natalia, Borojevic, Rajka, Nardelli, Andrea, Pinto-Sanchez, Maria Ines, Constante, Marco, Libertucci, Josie, Mohan, Vidhyalakshmi, Langella, Philippe, Loonen, Linda M. P., Wells, Jerry M., Collins, Stephen M., Sokol, Harry, Verdu, Elena F., Bercik, Premysl
• Format: Journal Article
• Language: English
• Published: United States American Physiological Society 01.06.2024
• Subjects: Administration, Oral; Adult; Amino acids; Basic Helix-Loop-Helix Transcription Factors; Cell activation; Cross-Over Studies; Cytokines; Cytokines - metabolism; Dietary Supplements; Double-Blind Method; Duodenum - drug effects; Duodenum - metabolism; Enzyme-linked immunosorbent assay; Feces - chemistry; Feces - microbiology; Female; Gastrointestinal Microbiome - drug effects; Healthy Volunteers; Homeostasis; Humans; Hydrocarbons; Immunomodulation; Indoles - administration & dosage; Indoles - pharmacology; Inflammation; Kynurenine - metabolism; Life Sciences; Liquid chromatography; Male; Mass spectroscopy; Metabolic pathways; Metabolites; Microbiology and Parasitology; Microbiomes; Microbiota; Monocytes; Nutrient deficiency; Placebos; Receptors, Aryl Hydrocarbon - metabolism; rRNA 16S; Small intestine; Tryptophan; Tryptophan - administration & dosage; Tryptophan - metabolism; Young Adult; kynurenine; indole; microbiome; tryptophan; aryl hydrocarbon receptor

We demonstrate that in healthy subjects, orally administered tryptophan activates microbial indole and host kynurenine pathways in the small intestine, the primary metabolic site for dietary components, and the richest source of immune cells along the gut. This study provides novel insights in how t...