Gut Microbiota-driven Tryptophan Metabolism Towards the Indole Pathway Mediates Schisandra Chinensis Polysaccharide's Alleviation of Ulcerative Colitis and Comorbid Depression via Aryl Hydrocarbon Receptor
Abstract
) and rebalanced Trp metabolism along the gut-brain axis. SCP suppressed the hyperactive kynurenine (Kyn) pathway (reduced Kyn/Trp ratio) while elevating indole-3-propionic acid (IPA) levels in colon, serum, and hippocampus. Functioning as a pivotal molecule, IPA exerted dual anti-inflammatory effects in both colon and hippocampus via AhR activation and NF-κB inhibition. Antibiotic depletion and fecal microbiota transplantation validated SCP's microbiota-dependent efficacy, while IPA supplementation recapitulated SCP's benefits. AhR inhibition abolished SCP's therapeutic actions, confirming AhR as the critical target. Collectively, these findings propose a novel therapeutic strategy for UC and associated depression, highlighting SCP's potential value in targeting the Trp metabolism-AhR axis.
Fields of Study & Subjects
Tryptophan and brain disorders
Gut microbiota and health
Plant-derived Lignans Synthesis and Bioactivity
Publication details
- Journal / source
- International Journal of Biological Sciences
- Publisher
- Ivyspring International Publisher
- Volume
- 22
- Issue
- 5
- Pages
- 2557–2580
- Publication date
- 11 February 2026
- Language
- EN