ArticleBrain, behavior, and immunity2015
Reduction of kynurenic acid to quinolinic acid ratio in both the depressed and remitted phases of major depressive disorder.
Article in Brain, behavior, and immunity, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 115 papers, 5 of them syntheses that pooled it.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
115 citing papers in PubMed, 5 syntheses or guidelines pooled it, 199 citations in OpenAlex.
- Pooled it
- Pooled it
- Systematic Review of the Kynurenine Pathway and Psychoneurological Symptoms Among Adult Cancer Survivors.Biological research for nursing · 2020Pooled it
- Inflammatory markers in depression: A meta-analysis of mean differences and variability in 5,166 patients and 5,083 controls.Brain, behavior, and immunity · 2020Pooled it
- Replication and reproducibility issues in the relationship between C-reactive protein and depression: A systematic review and focused meta-analysis.Brain, behavior, and immunity · 2018Pooled it
- Kynurenine metabolism and inflammation-induced depressed mood: A human experimental study.Psychoneuroendocrinology · 2019Trial
- The Tryptophan-Kynurenine Pathway as a Key Mediator of the Gut-Brain Axis in Depression and Alzheimer's Disease.International journal of molecular sciences · 2026Review
- Changes in leukocytes and CRP in different treatments of major depression.Journal of neural transmission (Vienna, Austria : 1996) · 2026Article
- PMiScience · 2026Review
- Dietary Tryptophan Allocation in Depression: Serotonin-Kynurenine Balance, Microbial Indole Pathways, and Inflammatory Phenotypes.Nutrients · 2026Review
- Changes in kynurenine pathway metabolites and brain structure in response to behavioral activation therapy.Brain, behavior, and immunity · 2026Article
- Combining neurobiological markers and a sociodemographic risk score to predict adolescent depression - An IDEA RiSCo prospective cohort study.Molecular psychiatry · 2026Article
- The kynurenine pathway in relation to depression and anhedonia symptom severity among women with HIV.Brain, behavior, & immunity - health · 2026Article
- Kynurenine pathway metabolites are increased in inflammatory depression and decrease with omega-3 treatment.Brain, behavior, & immunity - health · 2026Article
- Cognitive Improvement and Microbiota-Gut-Brain Axis Regulation byMicroorganisms · 2026Article
- Non-severe burn injury leads to sustained molecular changes in the brain in a murine model.Scientific reports · 2026Article
- Kynurenine pathway dysregulation in major depressive disorder: the convergence of excitotoxicity, neuroinflammation, and oxidative stress.Journal of neuroinflammation · 2026Review
- Review
- Contextual Regulation of the Kynurenine Pathway and Its Relevance for Personalized Psychiatry.Journal of personalized medicine · 2026Review
- Microglia-derived metabolites as novel signaling molecules: regulating neural circuit function, behavior, and their role in psychiatric disorders.Frontiers in cellular neuroscience · 2026Review
55 more citing papers are in PubMed but not listed here.
Corrections and comments
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Authors and funding
9 authors at 5 institutions in 1 country.
Funding
Abstract
Low-grade inflammation is characteristic of a subgroup of currently depressed patients with major depressive disorder (dMDD). It may lead to the activation of the kynurenine-metabolic pathway and the increased synthesis of potentially neurotoxic metabolites such as 3-hydroxykynurenine (3HK) and quinolinic acid (QA), relative to kynurenic acid (KynA). Nevertheless, few studies have examined whether abnormalities in this pathway are present in remitted patients with MDD (rMDD). Here we compared the serum concentrations of kynurenine metabolites, measured using high performance liquid chromatography with tandem mass spectrometry, across 49 unmedicated subjects meeting DSM-IV-TR criteria for MDD, 21 unmedicated subjects meeting DSM-IV-TR criteria for rMDD, and 58 healthy controls (HCs). There was no significant group difference in the concentrations of the individual kynurenine metabolites, however both the dMDD group and the rMDD group showed a reduction in KynA/QA, compared with the HCs. Further, there was an inverse correlation between KynA/QA and anhedonia in the dMDD group, while in the rMDD group, there was a negative correlation between lifetime number of depressive episodes and KynA/QA as well as a positive correlation between the number of months in remission and KynA/QA. Our results raise the possibility that a persistent abnormality exists within the kynurenine metabolic pathway in MDD that conceivably may worsen with additional depressive episodes. The question of whether persistent abnormalities in kynurenine metabolism predispose to depression and/or relapse in remitted individuals remains unresolved.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.