IDO (indoleamine 2,3-dioxygenase) activity reflects the rate at which the amino acid tryptophan is converted into kynurenine. This pathway is regulated by immune and inflammatory signals, particularly cytokines such as interferon-γ. Increased IDO activity (low tryptophan/kynurenine ratio) may indicate immune activation, chronic inflammation, or oxidative stress. Balanced IDO activity suggests normal immune regulation and sufficient tryptophan availability for serotonin and melatonin synthesis.
IDO (indoleamine 2,3-dioxygenase) activity indicates how actively the amino acid tryptophan is converted into kynurenine. This pathway is closely connected to immune regulation and inflammation, as it is triggered by cytokines such as interferon-γ.
Higher IDO activity (indicated by a lower tryptophan/kynurenine ratio) may signify immune activation, chronic inflammation, infection, or oxidative stress. It indicates that tryptophan is being redirected from serotonin production toward immune-related metabolic pathways.
Low IDO activity (a higher tryptophan/kynurenine ratio) may indicate reduced immune activation or low inflammatory signaling. It can also suggest sufficient tryptophan availability for serotonin and melatonin synthesis.
Supporting balanced immune and inflammatory function is essential. Adequate antioxidant intake, stress reduction, and maintaining healthy gut and immune function may help regulate IDO activity. Ensuring sufficient dietary tryptophan and cofactors like B vitamins and magnesium supports optimal tryptophan metabolism.