Programmed Necrosis RIPK1-RIPK3 Complex Mediates Sevoflurane-induced Developmental Neurotoxicity

OBJECTIVE To examine that programmed necrosis RIPK1-RIPK3 complex participates in the mechanism of developmental sevoflurane neurotoxicity. METHODS The developmental sevoflurane neurotoxicity model was established by exposure of primary hippocampal neurons(7 d in vitro) and SD rat pups(7 postnatal days) with sevoflurane(3%, 6 h). The gene chip was used to detect the mRNA levels of the targeted genes. The CO-immunoprecipitation and immunoblotting were performed to explore the combination and expression differences of targeted proteins. The developmental sevoflurane neurotoxicity was determined by TUNEL-staining. The spatial learning and memory functions were examined by Morris Water Maze. RESULTS Sevoflurane exposure(3%, 6 h) significantly enhanced the mRNA levels of Ripk1, Ripk3, Mlkl and Daxx. These results were confirmed by Western blot in protein level. Sevoflurane treatment dramatically increased TUNEL-positive neurons. In addition, administration of RIPK1-RIPK3-specific inhibitor Nec-1 significantly decreased TUNEL-positive neurons. Furthermore, treatment with Nec-1 significantly improved the spatial cognitive disorders which was decreased by postnatal sevoflurane exposure. CONCLUSION These data suggest that programmed necrosis participates in developmental sevoflurane neurotoxicity, and its mechanism may be related to the RIPK1-RIPK3 complex mediating MLKL and Daxx signaling pathways.