ArticleScientific reports2020
The relationship between blood metabolites of the tryptophan pathway and kidney function: a bidirectional Mendelian randomization analysis.
Article in Scientific reports, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 34 papers.
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Who cites it
34 citing papers in PubMed, 50 citations in OpenAlex.
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- Modelling ischaemic AKI in human kidney organoids reveals injury-associated epithelial states and macrophage-epithelial crosstalk.Genome medicine · 2026Article
- Lifestyles, metabolome and diabetic kidney disease: a cohort study.QJM : monthly journal of the Association of Physicians · 2026Article
- Sexual dimorphism shapes renal metabolic adaptation to a ketogenic diet.Cell reports · 2026Article
- Untangling amino acid metabolism in renal diseases: mechanisms, dysregulation, and critical gaps.Clinical kidney journal · 2026Review
- Gut microbiota and kidney aging: insights into current research.Nutrition & metabolism · 2025Review
- Article
- Systematic metabolomics study in the serum and urine of a mouse model of Fabry disease.Kidney research and clinical practice · 2025Article
- Temporal Changes in Blood Metabolome Among Patients on Hemodialysis.Kidney international reports · 2025Article
- Predicting diabetic kidney disease with serum metabolomics and gut microbiota.Scientific reports · 2025Article
- Amino acid metabolism in kidney health and disease.Nature reviews. Nephrology · 2024Review
- Review of Exercise Interventions to Improve Clinical Outcomes in Nondialysis CKD.Kidney international reports · 2024Review
- Molecular mechanisms and therapeutic significance of Tryptophan Metabolism and signaling in cancer.Molecular cancer · 2024Review
- A tryptophan-derived uremic metabolite/Ahr/Pdk4 axis governs skeletal muscle mitochondrial energetics in chronic kidney disease.JCI insight · 2024Article
- Metabolic implications of amino acid metabolites in chronic kidney disease progression: a metabolomics analysis using OPLS-DA and MBRole2.0 database.International urology and nephrology · 2024Article
- Evaluation of novel candidate filtration markers from a global metabolomic discovery for glomerular filtration rate estimation.Kidney international · 2024Article
- Indole Lactic Acid in Plasma and Urine: A Potential Biomarker for Chronic Kidney Disease and Inflammatory.Journal of inflammation research · 2024Article
- Circulating metabolites associated with kidney function decline and incident CKD: a multi-platform population-based study.Clinical kidney journal · 2024Article
- Current and Novel Biomarkers of Progression Risk in Children with Chronic Kidney Disease.Nephron · 2024Review
- Plasma Serotonin and Cardiovascular Outcomes in Chronic Kidney Disease.Journal of the American Heart Association · 2023Article
Corrections and comments
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Authors and funding
6 authors at 3 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Blood metabolites of the tryptophan pathway were found to be associated with kidney function and disease in observational studies. In order to evaluate causal relationship and direction, we designed a study using a bidirectional Mendelian randomization approach. The analyses were based on published summary statistics with study sizes ranging from 1,960 to 133,413. After correction for multiple testing, results provided no evidence of an effect of metabolites of the tryptophan pathway on estimated glomerular filtration rate (eGFR). Conversely, lower eGFR was related to higher levels of four metabolites: C-glycosyltryptophan (effect estimate = - 0.16, 95% confidence interval [CI] (- 0.22; - 0.1); p = 9.2e-08), kynurenine (effect estimate = - 0.18, 95% CI (- 0.25; - 0.11); p = 1.1e-06), 3-indoxyl sulfate (effect estimate = - 0.25, 95% CI (- 0.4; - 0.11); p = 6.3e-04) and indole-3-lactate (effect estimate = - 0.26, 95% CI (- 0.38; - 0.13); p = 5.4e-05). Our study supports that lower eGFR causes higher blood metabolite levels of the tryptophan pathway including kynurenine, C-glycosyltryptophan, 3-indoxyl sulfate, and indole-3-lactate. These findings aid the notion that metabolites of the tryptophan pathway are a consequence rather than a cause of reduced eGFR. Further research is needed to specifically examine relationships with respect to chronic kidney disease (CKD) progression among patients with existing CKD.
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