ArticleEBioMedicine2024
Tryptophan degradation as a systems phenomenon in inflammation - an analysis across 13 chronic inflammatory diseases.
Article in EBioMedicine, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 37 papers.
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Who cites it
37 citing papers in PubMed, 39 citations in OpenAlex.
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- Plasma metabolomic and lipidomic profiling reveals distinct molecular signatures and time-dependent remodeling in ulcerative colitis.BMC gastroenterology · 2026Article
- A metabolic constraint in de novo NAD+ synthesis drives mucosal inflammation in IBD.Journal of Crohn's & colitis · 2026Article
- Tryptophan pathway metabotypes associate with disease activity and immune-metabolic dysfunction in inflammatory bowel disease.medRxiv : the preprint server for health sciences · 2026Article
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- Metabolic profiles of amino acids in patients with crohn's disease-associated perianal fistulas and cryptoglandular anal fistulas.Scientific reports · 2026Article
- Multi-omics analyses reveal significant differences in the gut microbiota and metabolites in children with Kawasaki disease in Northwest China.Frontiers in immunology · 2026Article
- Sarcopenia and sepsis fuel a self-perpetuating cycle of immunometabolism decline.Frontiers in immunology · 2026Review
- Systematic Screening of Tryptophan Metabolism Identifies Site- and Microbiota-Dependent Signatures of Tryptophan Utilization in Experimental Colitis.International journal of tryptophan research : IJTR · 2026Article
- Bronchoalveolar Lavage Fluid Microbial and Metabolic Alterations Associated with Acute Respiratory Distress Syndrome in Hospitalized Patients with Community-Acquired Pneumonia.Journal of inflammation research · 2026Article
- Systems biology insights into the molecular drivers of childhood stunting and implications for intervention.Frontiers in nutrition · 2026Review
- Impact of COVID-19 on inflammatory disease research: a literature analysis of 77,575 PubMed articles.Reumatologia · 2026Article
- The kynurenine pathway in depression and schizophrenia: convergent signals, divergent states, and clinical signatures.EXCLI journal · 2026Review
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- Tracing NADResearch square · 2025Article
- GPR35 mediates monocyte recruitment to the sites of Listeria monocytogenes infection.Cellular and molecular life sciences : CMLS · 2025Article
- Integrating multi-omics data to reveal the host-microbiota interactome in inflammatory bowel disease.Gut microbes · 2025Review
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Authors and funding
22 authors at 6 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundChronic inflammatory diseases (CIDs) are systems disorders that affect diverse organs including the intestine, joints and skin. The essential amino acid tryptophan (Trp) can be broken down to various bioactive derivatives important for immune regulation. Increased Trp catabolism has been observed in some CIDs, so we aimed to characterise the specificity and extent of Trp degradation as a systems phenomenon across CIDs.
methodsWe used high performance liquid chromatography and targeted mass spectrometry to assess the serum and stool levels of Trp and Trp derivatives. Our retrospective study incorporates both cross-sectional and longitudinal components, as we have included a healthy population as a reference and there are also multiple observations per patient over time.
findingsWe found reduced serum Trp levels across the majority of CIDs, and a prevailing negative relationship between Trp and systemic inflammatory marker C-reactive protein (CRP). Notably, serum Trp was low in several CIDs even in the absence of measurable systemic inflammation. Increases in the kynurenine-to-Trp ratio (Kyn:Trp) suggest that these changes result from increased degradation along the kynurenine pathway.
interpretationIncreases in Kyn:Trp indicate the kynurenine pathway as a major route for CID-related Trp metabolism disruption and the specificity of the network changes indicates excessive Trp degradation relative to other proteogenic amino acids. Our results suggest that increased Trp catabolism is a common metabolic occurrence in CIDs that may directly affect systemic immunity.
fundingThis work was supported by the DFG Cluster of Excellence 2167 "Precision medicine in chronic inflammation" (KA, SSchr, PR, BH, SWa), the BMBF (e:Med Juniorverbund "Try-IBD" 01ZX1915A and 01ZX2215, the e:Med Network iTREAT 01ZX2202A, and GUIDE-IBD 031L0188A), EKFS (2020_EKCS.11, KA), DFG RU5042 (PR, KA), and Innovative Medicines Initiative 2 Joint Undertakings ("Taxonomy, Treatments, Targets and Remission", 831434, "ImmUniverse", 853995, "BIOMAP", 821511).
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