SynthesisGeroScience2026
Kynurenine pathway dysregulation in cognitive impairment and dementia: a systematic review and meta-analysis.
Synthesis in GeroScience, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.
What it found
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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.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
9 citing papers in PubMed.
- 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
- Gut Microbiota-Targeted Nutrition for Healthy Aging: Mechanistic Roles of Polyphenols and Dietary Fiber in Geroscience.Nutrients · 2026Review
- Biochemical and Pharmacological Studies on Kynurenic Acid Metabolism in theBiomolecules · 2026Article
- Immune-proteo-metabolomic changes link to Aβ and tau pathology in Alzheimer disease.Alzheimer's & dementia : the journal of the Alzheimer's Association · 2026Article
- The mGluR2/3 agonist xanthurenic acid improves memory, attention, and synaptic deficits by modulating glutamate release in Alzheimer's disease model.Acta pharmacologica Sinica · 2026Article
- The kynurenine pathway in depression and schizophrenia: convergent signals, divergent states, and clinical signatures.EXCLI journal · 2026Review
- Treg-microglia crosstalk in Alzheimer's disease: stage-dependent dynamics, molecular mechanisms, and translational challenge.Frontiers in aging neuroscience · 2026Review
- Kynurenine Pathway Metabolites as Mediators of Exercise-Induced Mood Enhancement, Fatigue Resistance, and Neuroprotection.International journal of molecular sciences · 2025Review
- Gpr35 Expression Mitigates Neuroinflammation and Enriches GutResearch (Washington, D.C.) · 2025Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
9 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The kynurenine pathway (KP) might be involved in pathophysiological processes associated with dementia, but clinical studies reported contradictory results. This systematic review and meta-analysis summarized the available evidence for (i) differences in KP metabolites in patients with cognitive impairment compared to cognitively healthy individuals and (ii) associations between KP metabolites and cognitive functioning. English, full-length articles with prospective, cross-sectional, or case-control study designs, published in Pubmed, Embase, PsychINFO, or the Cochrane Database of Systematic Reviews up to October 2023, were included. Random-effects meta-analyses of standardized mean differences (SMD) were performed. Heterogeneity, meta-regression, small study bias, and study quality assessments were carried out. Of 8797 retrieved studies, 98 were eligible for the systematic review. Meta-analyses comparing Alzheimer's disease (AD) dementia patients to controls (n = 27 studies) indicated lower CSF levels of tryptophan (SMD = - 0.26 [95% CI - 0.41, - 0.12]), 3-hydroxykynurenine (- 0.21 [- 0.39, - 0.04]), anthranilic acid (- 0.28 [- 0.48, - 0.08]), and quinolinic acid (- 0.38 [- 0.56, - 0.21]) in AD dementia, while CSF levels of kynurenic acid were higher (0.18 [0.01, 0.35]). Blood levels of tryptophan (- 0.39 [- 0.51, - 0.28]), kynurenic acid (- 0.31 [- 0.47, - 0.15]), xanthurenic acid (- 0.34 [- 0.54, - 0.15]), and 3-hydroxyanthranilic acid (- 0.42 [- 0.61, - 0.22]) were lower in AD dementia. For some of these metabolites, similar directions were observed in meta-analyses comparing individuals with mild cognitive impairment with controls, although the number of included studies in these analyses was relatively small (n = 11). Associations with cognitive test scores were inconclusive and generally non-significant. These results suggest that AD dementia is associated with lower blood levels of several KP metabolites. Findings challenge current assumptions of neurotoxic quinolinic acid levels being associated with dementia.
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Registered trials
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 Socratic graph.