Necrostatin‐1 protects against glutamate‐induced glutathione depletion and caspase‐independent cell death in HT‐22 cells

Abstract

Glutamate, a major excitatory neurotransmitter in the CNS, plays a critical role in neurological disorders such as stroke and Parkinson’s disease. Recent studies have suggested that glutamate excess can result in a form of cell death called glutamate‐induced oxytosis. In this study, we explore the protective effects of necrostatin‐1 (Nec‐1), an inhibitor of necroptosis, on glutamate‐induced oxytosis. We show that Nec‐1 inhibits glutamate‐induced oxytosis in HT‐22 cells through a mechanism that involves an increase in cellular glutathione (GSH) levels as well as a reduction in reactive oxygen species production. However, Nec‐1 had no protective effect on free radical‐induced cell death caused by hydrogen peroxide or menadione, which suggests that Nec‐1 has no antioxidant effects. Interestingly, the protective effect of Nec‐1 was still observed when cellular GSH was depleted by buthionine sulfoximine, a specific and irreversible inhibitor of glutamylcysteine synthetase. Our study further demonstrates that Nec‐1 significantly blocks the nuclear translocation of apoptosis‐inducing factor (a marker of caspase‐independent programmed cell death)and inhibits the integration of Bcl‐2/adenovirus E1B 19 kDa‐interacting protein 3 (a pro‐death member of the Bcl‐2 family) into the mitochondrial membrane. Taken together, these results demonstrate for the first time that Nec‐1 prevents glutamate‐induced oxytosis in HT‐22 cells through GSH related as well as apoptosis‐inducing factor and Bcl‐2/adenovirus E1B 19 kDa‐interacting protein 3‐related pathways.