Tryptophan metabolites from host and gut bacteria influence oxidative stress and inflammation through aryl hydrocarbon receptor signaling

Aryl hydrocarbon receptor (AhR) is associated with the regulation of redox homeostasis and immune responses.

• AhR is a transcription factor that activates genes involved in various biological processes.
• Research is shifting focus from xenobiotic-induced AhR activation to its response to physiological ligands.
• Host/gut microbiota-derived tryptophan metabolites serve as significant endogenous ligands for AhR.
• AhR signaling pathways can be categorized into canonical and non-canonical mechanisms.
• Evidence suggests that AhR influences oxidative stress and inflammation in conditions like diabetes and kidney disease.
• The review highlights both limitations and potential breakthroughs regarding endogenous AhR ligands derived from tryptophan catabolism.

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