Sleep has a regulatory role in maintaining metabolic homeostasis and cellular functions.
Inadequate sleep time and
sleep disorders have become more prevalent in the modern lifestyle. Fragmentation of sleep pattern alters critical intracellular second messengers and
neurotransmitters which have key functions in brain development and behavioral functions.
Tryptophan metabolism has also been found to get altered in SD and it is linked to various
neurodegenerative diseases. The
kynurenine pathway is a major regulator of the immune response. Adequate sleep alleviates
neuroinflammation and facilitates the cellular clearance of metabolic toxins produced within the brain, while
sleep deprivation activates the enzymatic degradation of
tryptophan via the
kynurenine pathway, which results in an increased accumulation of neurotoxic metabolites. SD causes increased production and accumulation of
kynurenic acid in various regions of the brain. Higher levels of
kynurenic acid have been found to trigger apoptosis, leads to
cognitive decline, and inhibit neurogenesis. This review aims to link the impact of
sleep deprivation on
tryptophan metabolism and associated complication in the brain.