ArticleBrain, behavior, and immunity2022
Peripheral and central kynurenine pathway abnormalities in major depression.
Article in Brain, behavior, and immunity, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 63 papers.
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Who cites it
63 citing papers in PubMed, 116 citations in OpenAlex.
- Acute administration of ibuprofen increases serum concentration of the neuroprotective kynurenine pathway metabolite, kynurenic acid: a pilot randomized, placebo-controlled, crossover study.Psychopharmacology · 2022Trial
- The role of zinc homeostasis in major depressive disorder: heterogeneous pathological mechanisms and therapeutic implications.Annals of medicine · 2026Review
- 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
- Dietary Tryptophan Allocation in Depression: Serotonin-Kynurenine Balance, Microbial Indole Pathways, and Inflammatory Phenotypes.Nutrients · 2026Review
- Association Between Kynurenine Pathway and Cerebellar Microstructure in Bipolar Disorder With Childhood Trauma.Alpha psychiatry · 2026Article
- Integrated biomarkers of oxidative stress NLRP3 inflammasome and kynurenine pathway reflect disease severity and diagnostic discrimination in depression.Scientific reports · 2026Article
- Changes in kynurenine pathway metabolites and brain structure in response to behavioral activation therapy.Brain, behavior, and immunity · 2026Article
- The role of proinflammatory response and the kynurenine pathway in the association between childhood maltreatment and lifetime substance use disorder.Neurobiology of stress · 2026Article
- Sex-specific microbial and tryptophan signatures of depression implicate archaeal methanogens and indole-3-acetic acid only in women.NPJ biofilms and microbiomes · 2026Article
- Major depressive disorder shares systemic immune signatures and potential therapeutic targets with inflammatory skin diseases.Molecular psychiatry · 2026Article
- Zinc Ameliorates LPS-Induced Depressive-Like Behaviors Via Modulating Microglial Polarization.Biological trace element research · 2026Article
- Kynurenine Pathway, Nrf2 and NF-κB Cross-Regulation in the CNS: An Overview.Molecular neurobiology · 2026Review
- The role of the kynurenine pathway in conditioned place aversion induced by synthetic cannabinoid CP-55940.Behavioral and brain functions : BBF · 2026Article
- Analysis of the correlation between the expression levels of caspase-1/IL-1β in the peripheral blood and clinical efficacy in patients with first-episode MDD.Annals of general psychiatry · 2026Article
- The adiponectin-depression nexus: a brief review of mechanisms and therapeutic opportunities.Metabolic brain disease · 2026Review
- Serum inflammatory cytokines in the progression of depression.Frontiers in immunology · 2026Review
- Linking inflammatory and structural neuroimaging biomarkers in treatment-resistant depression: Current evidence and emerging hypotheses.Neuroscience applied · 2026Review
- The kynurenine pathway in pediatric "mild-to-moderate" traumatic brain injury: translational insights from a prospective human study and a large-animal model.Brain, behavior, and immunity · 2026Article
- The kynurenine pathway in depression and schizophrenia: convergent signals, divergent states, and clinical signatures.EXCLI journal · 2026Review
- Depression and breast cancer: research progress and prospects from an interdisciplinary perspective.Frontiers in immunology · 2026Review
3 more citing papers are in PubMed but not listed here.
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Authors and funding
13 authors at 3 institutions in 2 countries.
Funding
Abstract
Considerable data relate major depressive disorder (MDD) with aberrant immune system functioning. Pro-inflammatory cytokines facilitate metabolism of tryptophan along the kynurenine pathway (KP) putatively resulting in reduced neuroprotective and increased neurotoxic KP metabolites in MDD, in addition to modulating metabolic and immune function. This central nervous system hypothesis has, however, only been tested in the periphery. Here, we measured KP-metabolite levels in both plasma and cerebrospinal fluid (CSF) of depressed patients (n = 63/36 respectively) and healthy controls (n = 48/33). Further, we assessed the relation between KP abnormalities and brain-structure volumes, as well as body mass index (BMI), an index of metabolic disturbance associated with atypical depression. Plasma levels of picolinic acid (PIC), the kynurenic/quinolinic acid ratio (KYNA/QUIN), and PIC/QUIN were lower in MDD, but QUIN levels were increased. In the CSF, we found lower PIC in MDD. Confirming previous work, MDD patients had lower hippocampal, and amygdalar volumes. Hippocampal and amygdalar volumes were correlated positively with plasma KYNA/QUIN ratio in MDD patients. BMI was increased in the MDD group relative to the control group. Moreover, BMI was inversely correlated with plasma and CSF PIC and PIC/QUIN, and positively correlated with plasma QUIN levels in MDD. Our results partially confirm previous peripheral KP findings and extend them to the CSF in MDD. We present the novel finding that abnormalities in KP metabolites are related to metabolic disturbances in depression, but the relation between KP metabolites and depression-associated brain atrophy might not be as direct as previously hypothesized.
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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.