Sestrin-2 also known as Hi95 is a protein that in humans is encoded by the SESN2 gene. [5] [6] [7]
This gene encodes a member of the sestrin family of PA26-related proteins. The encoded protein may function in the regulation of cell growth and survival. This protein may be involved in cellular response to different stress conditions. [7] [8] The Sestrins constitute a family of evolutionarily-conserved stress-inducible proteins that suppress oxidative stress and regulate adenosine monophosphate-dependent protein kinase (AMPK)-mammalian target of rapamycin (mTOR) signaling. By virtue of these activities, the Sestrins serve as important regulators of metabolic homeostasis. [9] Accordingly, inactivation of Sestrin genes in invertebrates resulted in diverse metabolic pathologies, including oxidative damage, fat accumulation, mitochondrial dysfunction and muscle degeneration that resemble accelerated tissue aging. [7] [10]
The NMDA receptor antagonist ketamine has been found to activate the mammalian target of rapamycin complex 1 (mTORC1) pathway in the medial prefrontal cortex (mPFC) of the brain as an essential downstream mechanism in the mediation of its rapid-acting antidepressant effects. [11] NV-5138 is a ligand and modulator of sestrin2, a leucine amino acid sensor and upstream regulatory pathway of mTORC1, and is under development for the treatment of depression. [11] The drug has been found to directly and selectively activate the mTORC1 pathway, including in the mPFC, and to produce rapid-acting antidepressant effects similar to those of ketamine. [11]