preclinical_heavy
Preclinical evidence exceeds central human evidence. Interpret translational relevance cautiously.
supportedtophigh inflation risk
Tryptophan metabolism
inflammatory bowel disease
Tryptophan metabolism has meaningful literature visibility in inflammatory bowel disease, but the current evidence mix suggests a substantial risk of overclaiming.
Tryptophan metabolism shows a moderate evidence base in inflammatory bowel disease, with multiple central papers and additional supporting literature.
tryptophan_metabolism
Credibility score
48
Human translation
1/5
Reproducibility
5/5
Novelty
2/5
Actionability
2/5
Credibility 48Human translation 1/5Reproducibility 5/5Novelty 2/5Actionability 2/5
Why this scores the way it does
- moderate central evidence base
- dense review literature
- substantial preclinical support
Main caveats
- preclinical evidence outweighs human evidence
- review density exceeds central evidence depth
- retrieval noise or disease-specificity issues may remain
Internal review flags
2 flagsreview_heavy
Review literature is very dense relative to primary central evidence.
Primary central evidence
7 papersLow-Fat, High-Fiber Diet Reduces Markers of Inflammation and Dysbiosis and Improves Quality of Life in Patients With Ulcerative Colitis.
2021Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association
Direct disease-relevant human paper with strong clinical, biomarker, or mechanistic framing.
Inflammatory bowel disease-associated Escherichia coli strain LF82 in the damage of gut and cognition of honeybees.
2022Frontiers in cellular and infection microbiology
Direct disease-relevant human paper with strong clinical, biomarker, or mechanistic framing.
Tryptophan Metabolism 'Hub' Gene Expression Associates with Increased Inflammation and Severe Disease Outcomes in COVID-19 Infection and Inflammatory Bowel Disease.
2022International journal of molecular sciences
Direct disease-relevant human paper with strong clinical, biomarker, or mechanistic framing.
Decreased Serum Tryptophan and Severe Ulcerative Damage of Colon Mucosa Identify Inflammatory Bowel Disease Patients With High Risk of Cytomegalovirus Colitis.
2024Clinical and translational gastroenterology
Direct disease-relevant human paper with strong clinical, biomarker, or mechanistic framing.
Novel cross-feeding human gut microbes metabolizing tryptophan to indole-3-propionate.
2025Gut microbes
Direct disease-relevant human paper with strong clinical, biomarker, or mechanistic framing.
Impact of terminal ileal microbiota dysbiosis and tryptophan metabolism alterations on mental disorders in patients with Crohn's disease.
2025BMC gastroenterology
Direct disease-relevant human paper with strong clinical, biomarker, or mechanistic framing.
Deciphering the microbiome-metabolome landscape of an inflammatory bowel disease inception cohort.
2025Gut microbes
Direct disease-relevant human paper with strong clinical, biomarker, or mechanistic framing.
Supporting primary evidence
1 papersMolecular Mechanisms of Skatole-Induced Inflammatory Responses in Intestinal Epithelial Caco-2 Cells: Implications for Colorectal Cancer and Inflammatory Bowel Disease.
2024Cells
Human primary paper with plausible association relevance to the disease context.
Preclinical supporting evidence
23 papersCARD9 impacts colitis by altering gut microbiota metabolism of tryptophan into aryl hydrocarbon receptor ligands.
2016Nature medicine
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Indoleacrylic Acid Produced by Commensal Peptostreptococcus Species Suppresses Inflammation.
2017Cell host & microbe
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Microbial tryptophan metabolites regulate gut barrier function via the aryl hydrocarbon receptor.
2020Proceedings of the National Academy of Sciences of the United States of America
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Deletion of ghrelin alters tryptophan metabolism and exacerbates experimental ulcerative colitis in aged mice.
2022Experimental biology and medicine (Maywood, N.J.)
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Rewiring the altered tryptophan metabolism as a novel therapeutic strategy in inflammatory bowel diseases.
2023Gut
Disease-relevant preclinical or model-based paper useful as supporting evidence.
DSS-induced colitis activates the kynurenine pathway in serum and brain by affecting IDO-1 and gut microbiota.
2022Frontiers in immunology
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Pulsatilla chinensis saponins ameliorated murine depression by inhibiting intestinal inflammation mediated IDO1 overexpression and rebalancing tryptophan metabolism.
2023Phytomedicine : international journal of phytotherapy and phytopharmacology
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Wogonin improves colitis by activating the AhR pathway to regulate the plasticity of ILC3/ILC1.
2024Phytomedicine : international journal of phytotherapy and phytopharmacology
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Fat and proteolysis due to methionine, tryptophan, and niacin deficiency leads to alterations in gut microbiota and immune modulation in inflammatory bowel disease.
2024Cancer science
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Gut microbiota metabolite indole-3-acetic acid maintains intestinal epithelial homeostasis through mucin sulfation.
2024Gut microbes
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Ganoderic Acid A Mitigates Inflammatory Bowel Disease through Modulation of AhR Activity by Microbial Tryptophan Metabolism.
2024Journal of agricultural and food chemistry
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Vinegar-processed Schisandra Chinensis enhanced therapeutic effects on colitis-induced depression through tryptophan metabolism.
2024Phytomedicine : international journal of phytotherapy and phytopharmacology
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Clostridium sporogenes-derived metabolites protect mice against colonic inflammation.
2024Gut microbes
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Rewiring Tryptophan Metabolism via Programmable Probiotic Integrated by Dual-Layered Microcapsule Protects against Inflammatory Bowel Disease in Mice.
2024ACS nano
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Atractylodes macrocephala Koidz polysaccharide ameliorates DSS-induced colitis in mice by regulating the gut microbiota and tryptophan metabolism.
2025British journal of pharmacology
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Therapeutic potential of tryptophan metabolite indoleacrylic acid in inflammatory bowel disease: From cellular mechanisms to zebrafish stress-like behavior.
2025International immunopharmacology
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Gut microbiota-derived tryptophan metabolites regulated by Wuji Wan to attenuate colitis through AhR signaling activation.
2025Acta pharmaceutica Sinica. B
Disease-relevant preclinical or model-based paper useful as supporting evidence.
"Shield" Armed Programmable Probiotics Harboring α-Aminoadipate Aminotransferase Gene Regulate Tryptophan Metabolism and Gut Microbiota to Alleviate the Inflammatory Bowel Disease.
2025Journal of agricultural and food chemistry
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Prenatal supplementation with the gut-derived tryptophan metabolite indole-3-propionic acid alleviates colitis susceptibility in maternal immune-activated offspring mice.
2026Journal of advanced research
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Xanthohumol Alleviates Inflammatory Bowel Disease-Associated Osteoporosis via Regulating Gut Microbial Metabolites.
2025Phytotherapy research : PTR
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Akkermansia muciniphila-derived extracellular vesicles alleviate colitis-related cognitive impairment via tryptophan metabolic reprogramming of the gut‒brain axis.
2026Gut microbes
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Microbiota-derived IPA protects against colitis by regulating intestinal HMGCS2-mediated ketogenesis to facilitate mucosal healing.
2026Nature communications
Disease-relevant preclinical or model-based paper useful as supporting evidence.
A microbiota-IPA axis facilitates intestinal stem cell-mediated regeneration in colitis through a Hopx-associated program.
2026Nature communications
Disease-relevant preclinical or model-based paper useful as supporting evidence.
Review supporting evidence
26 papersComorbidity between depression and inflammatory bowel disease explained by immune-inflammatory, oxidative, and nitrosative stress; tryptophan catabolite; and gut-brain pathways.
2016CNS spectrums
Relevant review or meta-analysis for the signal-disease area.
Tissue metabolism and the inflammatory bowel diseases.
2017Journal of molecular medicine (Berlin, Germany)
Relevant review or meta-analysis for the signal-disease area.
Beneficial actions of microbiota-derived tryptophan metabolites.
2018Neurogastroenterology and motility
Relevant review or meta-analysis for the signal-disease area.
Impact of the Gut Microbiota on Intestinal Immunity Mediated by Tryptophan Metabolism.
2018Frontiers in cellular and infection microbiology
Relevant review or meta-analysis for the signal-disease area.
Gut microbiota-derived metabolites as key actors in inflammatory bowel disease.
2020Nature reviews. Gastroenterology & hepatology
Relevant review or meta-analysis for the signal-disease area.
Tryptophan Metabolism, Regulatory T Cells, and Inflammatory Bowel Disease: A Mini Review.
2020Mediators of inflammation
Relevant review or meta-analysis for the signal-disease area.
Dietary and Nutritional Approaches to the Management of Chronic Enteropathy in Dogs and Cats.
2021The Veterinary clinics of North America. Small animal practice
Relevant review or meta-analysis for the signal-disease area.
An Insight into the Roles of Dietary Tryptophan and Its Metabolites in Intestinal Inflammation and Inflammatory Bowel Disease.
2021Molecular nutrition & food research
Relevant review or meta-analysis for the signal-disease area.
Impact of Microbial Metabolites on Microbiota-Gut-Brain Axis in Inflammatory Bowel Disease.
2021International journal of molecular sciences
Relevant review or meta-analysis for the signal-disease area.
Tryptophan Metabolism and Gut-Brain Homeostasis.
2021International journal of molecular sciences
Relevant review or meta-analysis for the signal-disease area.
Tryptophan-kynurenine metabolism: a link between the gut and brain for depression in inflammatory bowel disease.
2021Journal of neuroinflammation
Relevant review or meta-analysis for the signal-disease area.
Tryptophan metabolites modulate inflammatory bowel disease and colorectal cancer by affecting immune system.
2022International reviews of immunology
Relevant review or meta-analysis for the signal-disease area.
Tryptophan-derived serotonin-kynurenine balance in immune activation and intestinal inflammation.
2021FASEB journal : official publication of the Federation of American Societies for Experimental Biology
Relevant review or meta-analysis for the signal-disease area.
Dietary Patterns and Gut Microbiota: The Crucial Actors in Inflammatory Bowel Disease.
2022Advances in nutrition (Bethesda, Md.)
Relevant review or meta-analysis for the signal-disease area.
Inflammatory Bowel Disease and COVID-19: How Microbiomics and Metabolomics Depict Two Sides of the Same Coin.
2022Frontiers in microbiology
Relevant review or meta-analysis for the signal-disease area.
Disturbances of the Gut Microbiota and Microbiota-Derived Metabolites in Inflammatory Bowel Disease.
2022Nutrients
Relevant review or meta-analysis for the signal-disease area.
IDO/Kynurenine; novel insight for treatment of inflammatory diseases.
2023Cytokine
Relevant review or meta-analysis for the signal-disease area.
The Involvement of Intestinal Tryptophan Metabolism in Inflammatory Bowel Disease Identified by a Meta-Analysis of the Transcriptome and a Systematic Review of the Metabolome.
2023Nutrients
Relevant review or meta-analysis for the signal-disease area.
The role of intestinal microbes on intestinal barrier function and host immunity from a metabolite perspective.
2023Frontiers in immunology
Relevant review or meta-analysis for the signal-disease area.
Gut Microbiota Metabolites: Unveiling Their Role in Inflammatory Bowel Diseases and Fibrosis.
2024Pharmaceuticals (Basel, Switzerland)
Relevant review or meta-analysis for the signal-disease area.
Untargeted faecal metabolomics for the discovery of biomarkers and treatment targets for inflammatory bowel diseases.
2024Gut
Relevant review or meta-analysis for the signal-disease area.
Tryptophan metabolism and the intestinal microbiota: Implications for inflammatory bowel disease.
2025Microbiological research
Relevant review or meta-analysis for the signal-disease area.
Regulatory roles of intestinal CD4+ T cells in inflammation and their modulation by the intestinal microbiota.
2025Gut microbes
Relevant review or meta-analysis for the signal-disease area.
Gut Microbiota Changes in Metabolic Dysfunction-Associated Steatohepatitis and Inflammatory Bowel Disease: Common Pathogenic Features.
2025Current issues in molecular biology
Relevant review or meta-analysis for the signal-disease area.
The gut microbiota and its metabolites: novel therapeutic targets for inflammatory bowel disease.
2025Frontiers in immunology
Relevant review or meta-analysis for the signal-disease area.
The role of Akkermansia muciniphila in the regulation of inflammatory bowel disease: intestinal immunity and metabolism.
2025Frontiers in immunology
Relevant review or meta-analysis for the signal-disease area.