Nuclear factor-κB signaling pathway and autophagy in inhaled sevoflurane-produced delayed myocardial protection in rats / 中华麻醉学杂志

ABSTRACT

Objective To evaluate nuclear factor (NF)-κB signaling pathway and autophagy in inhaled sevoflurane-produced delayed myocardial protection in rats.Methods Ninety-six adult male Sprague-Dawley rats,weighing 270-350 g,were randomly assigned into 6 groups (n =16 each):sham operation group (group S),ischemia-reperfusion (I/R) group,sevoflurane group (SEVO group),specific NF-κB inhibitor parthenolide (PTN)group,dimethyl sulfoxide (DMSO) group and PTN + sevoflurane group (PTN + SEVO group).The animals were anesthetized with intraperitoneal pentobarbital 50 mg/kg,intubated and mechanically ventilated.Myocardial I/R was induced by 30 min of occlusion of the left anterior descending branch of coronary artery followed by 2 h of reperfusion.In group I/R,33％ oxygen was inhaled for 2 h.In group SEVO,2.5％ sevoflurane was inhaled for 2 h.In groups PTN and DMSO,PTN 500 μg/kg and DMSO were administered intraperitoneally 15 min before oxygen inhalation respectively.In group PTN + SEVO,PTN 500 μg/kg was administered intraperitoneally 15 min before exposure to sevoflurane.Myocardial I/R was induced 24 h after intraperitoneal administration.Eight animals in each group were sacrificed immediately before ischemia and the hearts were removed to detect the NF-κB activity and expression of LC3-Ⅱ and cathepsin B.The left animals in each group were sacrificed at 2 h of reperfusion and the hearts were removed to determine the myocardial infarct size (by TTC staining).Results Compared with group S,the myocardial infarct size was significantly increased at 2 h of reperfusion in the other groups,and the NF-κB activity was significantly increased and the expression of LC3-Ⅱ and cathepsin B was up-regulated immediately before ischemia in group SEVO (P ＜ 0.05).Compared with group I/R,the NF-κB activity was significantly increased and the expression of LC3-Ⅱ and cathepsin B was up-regulated immediately before ischemia,and the myocardial infarct size was significantly reduced at 2 h of reperfusion in group SEVO (P ＜ 0.05).Compared with group SEVO,the NF-κB activity was significantly decreased and the expression of LC3-Ⅱ and cathepsin B was down-regulated immediately before ischemia,and the myocardial infarct size was significantly increased at 2 h of reperfusion in DMSO,PTN and PTN + SEVO groups (P ＜ 0.05).Conclusion NF-κB signaling pathway and autophagy are involved in inhaled sevoflurane-produced delayed nyocardial protection in rats.