Prebiotic and probiotic supplementation and the tryptophan-kynurenine pathway: A systematic review and meta analysis

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#humans #kynurenine #prebiotics #probiotics #tryptophan

Prebiotic and probiotic supplementation and the tryptophan-kynurenine pathway: A systematic review and meta analysis

Purton et al., 2021 | Neurosci Biobehav Rev | Meta Analysis

Citation

Purton Terry, Staskova Lada, ... Marx Wolfgang. Prebiotic and probiotic supplementation and the tryptophan-kynurenine pathway: A systematic review and meta analysis. Neurosci Biobehav Rev. 2021-Apr;123:1-13. doi:10.1016/j.neubiorev.2020.12.026

Abstract

This systematic review aimed to synthesise the results from studies investigating the effects of prebiotics and probiotics on kynurenine pathway metabolism. Thirteen studies were identified for inclusion, comprising 12 probiotic and two prebiotic arms. Participants included healthy individuals and individuals with various clinical conditions. Twelve metabolites were examined across the studies, using a range of biological samples. Across all interventions, 11 reported an effect on ≤ metabolite. Although limited by clinical and methodological heterogeneity, pooled analysis (n = 253) found probiotics to significantly affect serum kynurenine (g = 0.315, CI = 0.070 to 0.560, p = 0.012, 4 studies, I2 = 0%) and the kynurenine:tryptophan ratio (g = 0.442, CI = 0.074 to 0.810, p = 0.018, 4 studies, I2 = 42 %). Risk of bias across the studies was generally low. The results provide preliminary evidence that probiotics can modulate kynurenine pathway metabolism, with less evidence available regarding prebiotics. Future studies which further consider methodological confounds and sample characteristics are required, to establish intervention efficacy. PROSPERO registration #CRD42019154677.

Key Findings

PROSPERO registration #CRD42019154677.

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population various clinical conditions
Sample Size 253
Age Range See abstract
Condition See abstract

MeSH Terms

  • Humans
  • Kynurenine
  • Prebiotics
  • Probiotics
  • Tryptophan

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Research Support, Non-U.S. Gov't, Systematic Review
  • Vertical: probiotics

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09