Research

Hormonal

Activation of the kynurenine pathway via IDO/TDO enzymes during inflammation promotes immune tolerance and prevents hyperinflammation by depleting tryptophan and producing kynurenine, which activates the aryl hydrocarbon receptor (AhR) to drive regulatory T cell differentiation.

This paper highlights that the body's natural response to stress (inflammation) involves shifting tryptophan metabolism to protect against excessive immune damage. While not a direct supplement protocol, it suggests that maintaining healthy tryptophan metabolism and understanding the balance of immune response is crucial for aging. Future therapies might target this pathway, but currently, no specific dose is recommended for general use.

ModerateSupportsMEDIUM confidence
Activation of tryptophan (Trp) metabolism along the kynurenine (Kyn) pathway prevents hyperinflammation and induces long-term immune tolerance.
Freek J. H. Sorgdrager et al. · Frontiers in Immunology · 2019

Why this rating

The paper is a mini-review citing multiple animal models and observational human studies, but lacks direct clinical trial data on intervention outcomes.

Source

Tryptophan Metabolism in Inflammaging: From Biomarker to Therapeutic Target

Freek J. H. Sorgdrager et al. · Frontiers in Immunology · 2019

DOI 10.3389/fimmu.2019.02565

narrative_reviewCited 377×
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DOI resolved against Crossref · corpus check 2026-06-10

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