Monitoring the kynurenine system: Concentrations, ratios or what else?

The tryptophan-kynurenine metabolic pathway plays the most essential role in tryptophan metabolism, producing various endogenous bioactive molecules. The activation of the metabolic pathway is linked to the pathogenesis of a wide range of diseases. The calibration of the levels and the ratio of kynurenines has been attempted in search of biomarkers and diagnostic targets. This editorial introduces biosystems in close interaction with the kynurenine system and potential measures to assess a state of stress, which may lead to illnesses.

Automated summary

The tryptophan-kynurenine metabolic pathway is crucial in producing endogenous bioactive molecules, and its activation is linked to the pathogenesis of various diseases. Efforts have been made to calibrate the levels and ratios of kynurenines to identify biomarkers and diagnostic targets. This editorial discusses the interaction between biosystems and the kynurenine system, as well as potential measures to evaluate stress levels that may lead to illnesses.