Activation of Canonical Notch Signaling Pathway Is Involved in the Ischemic Tolerance Induced by Sevoflurane Preconditioning in Mice

作者：Qianzi Yang, Wenjun Yan, Xin Li, Lihong Hou, Hui Dong, Qiang Wang, Hailong Dong, Shiquan Wang, Xia Zhang, Lize Xiong · 发表于：Anesthesiology · 年份：2012 · DOI：10.1097/aln.0b013e31826cb469 · 被引用次数：55 · 研究领域：Cardiac Ischemia and Reperfusion、Neuroscience and Neuropharmacology Research、Anesthesia and Neurotoxicity Research

BACKGROUND: A wealth of evidence has demonstrated that sevoflurane preconditioning induces brain ischemic tolerance, but the mechanism remains poorly understood. This study was designed to investigate the role of canonical Notch signaling in the neuroprotection induced by sevoflurane preconditioning in a mouse model. METHODS: C57BL/6 mice were pretreated with 1-h sevoflurane exposure at a dose of 2.5% for 5 consecutive days. Twenty-four hours after the last exposure, all mice were subjected to focal cerebral ischemia by right middle cerebral artery occlusion for 60 min. Neurobehavioral scores, brain infarct volumes, and cellular apoptosis were determined at 72 h after reperfusion (n = 10 per group). The activation of Notch signaling was evaluated (n = 5 per group), and its role in ischemic tolerance was assessed by intraperitoneal administration of γ-secretase inhibitor DAPT (100 mg/kg, n = 10 per group) and conditional Notch-RBP-J knockout technique (n = 8 per group). RESULTS: Sevoflurane preconditioning reduced brain infarct volumes (42.5%), improved neurologic outcomes (P < 0.01 vs. control), and attenuated neuronal cell apoptosis (cells positive for terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick-end labeling reduced to 21.2%). The expression of Notch1 intracellular domain (1.35 folds) and the transcriptions of Hes1 (1.95 times) and Hes5 (1.48 times) were up-regulated. DAPT augmented the brain infarcts (1.64-fold) and decreased neurolog...