The kynurenine pathway is a metabolic pathway leading to the production of nicotinamide adenine dinucleotide (NAD+) from the degradation of the essential amino acid tryptophan.
The kynurenine pathway is involved in physiological functions such as behavior, sleep, thermo-regulation and pregnancy. There are also strong evidences of the kynurenine pathway involvement in neurotoxic mechanisms associated with several inflammatory neurological diseases, including AIDS dementia complex, Alzheimer’s disease, Huntington’s disease, Amyotrophic lateral sclerosis, Multiple sclerosis and Parkinson's disease.