Kynurenic acid

Kynurenic acid is a neuroprotective metabolite of the kynurenine pathway, produced from kynurenine via kynurenine aminotransferase enzymes in peripheral tissues and the brain, with exercise promoting its synthesis through skeletal muscle PGC-1alpha1 activation. Agudelo et al. (2014) demonstrated that exercise-induced muscle PGC-1alpha1 drives kynurenic acid production, protecting the brain from stress-induced depression-like behaviour. In saliva, elevated kynurenic acid reflects active muscular exercise metabolism and indicates exercise-related neuroprotection.