S-linolenoyl glutathione intake extends life-span and stress resistance via Sir-2.1 upregulation in Caenorhabditis elegans

Oxidative stress has a prominent role in life-span regulation of living organisms. One of the endogenous free radical scavenger systems is associated with glutathione (GSH), the most abundant nonprotein thiol in mammalian cells, acting as a major reducing agent and in antioxidant defense by maintaining a tight control over redox status. We have recently designed a series of novel S-acyl-GSH derivatives capable of preventing amyloid oxidative stress and cholinergic dysfunction in Alzheimer disease models, upon an increase in GSH intake. In this study we show that the longevity of the wild-type N2 Caenorhabditis elegans strain was significantly enhanced by dietary supplementation with linolenoyl-SG (lin-SG) thioester with respect to the ethyl ester of GSH, linolenic acid, or vitamin E. RNA interference analysis and activity inhibition assay indicate that life-span extension was mediated by the upregulation of Sir-2.1, a NAD-dependent histone deacetylase ortholog of mammalian SIRT1. In particular, lin-SG-mediated overexpression of Sir-2.1 appears to be related to the Daf-16 (FoxO) pathway. Moreover, the lin-SG derivative protects N2 worms from the paralysis and oxidative stress induced by Aβ/H2O2 exposure. Overall, our findings put forward lin-SG thioester as an antioxidant supplement triggering sirtuin upregulation, thus opening new future perspectives for healthy aging or delayed onset of oxidative-related diseases.