Elevation of Sestrin-2 expression attenuates Sevoflurane induced neurotoxicity

Sevoflurane, one of the most commonly used volatile anesthetics in clinical treatment, has been shown to induce a widespread increase in brain apoptosis. However, the underlying mechanism is still unknown. Sestrin 2 has been recently shown to regulate intracellular reactive oxygen species (ROS) levels and play a crucial role in p53-dependent antioxidant defenses. In this study, our results indicated that administration of Sevoflurane elevated the gene and protein expression of Sestrin-2 in a dose dependent manner in human neuroblastoma M17 cells. It was shown that silence of Sestrin-2 by small RNA interference (siRNA) ominously exacerbated the increase in intracellular ROS and reduction of SOD activity induced by Sevoflurane treatment. Notably, knockdown of Sestrin-2 in M17 cells significantly increases the number of apoptotic cells after treatment with Sevoflurane. Mechanistically, we also found that Sevoflurane treatment resulted in a reduced amount of the cytosolic anti-apoptotic protein Bcl-2 but an increased amount of Bax, which was exacerbated by knockdown of Sestrin-2. In addition, knockdown of Sestrin-2 remarkably increased the elevated cleaved Caspase-3 expression. Finally, we showed that the induction of Sestrin-2 by Sevoflurane was mediated by p53. These results suggest that the suppressive effects of Sestrin-2 on neuroapoptosis against the Sevoflurane anesthesia in neuronal cells might be associated with modulation of mitochondrial pathway.