麻醉和手术导致老年小鼠脑内能量代谢紊乱与m TOR信号通路的关系

Relationship between energy metabolism disorders and mammalian target of rapamycin(mTOR)signaling pathway in elderly mice induced by anesthesia and surgery

目的评价麻醉和手术导致老年小鼠脑内能量代谢紊乱与雷帕霉素靶蛋白(mTOR)信号通路的关系。方法选取健康雄性C57BL/6小鼠64只,18月龄,随机分为两组(n=32):对照组(C组)和麻醉手术组(A/S组)。于术后第3天进行Morris水迷宫测试;于术后第1和第3天时取海马组织,采用Western blot法检测GLUT1、mTOR和磷酸化m TOR(p-mTOR)的水平,计算p-mTOR/mTOR比值;采用ATP试剂盒检测海马ATP浓度;于术后第1天和第3天时取脑组织进行切片、免疫荧光染色,观察海马GLUT1和p-mTOR表达情况。结果两组小鼠潜伏期随时间变化呈降低趋势,其中A/S组小鼠在术后第6天潜伏期高于C组(P<0.01),两组小鼠潜伏期不存在时间和组间的交互作用(P>0.05)。术后第7天A/S组穿越平台次数和平台象限游泳时间均低于C组(P<0.01)。与C组比较,A/S组术后1、3 d时海马GLUT1表达减弱,p-mTOR表达增强(P<0.01)。与C组比较,A/S组术后1、3 d时海马GLUT1水平降低,p-mTOR/mTOR比值升高(P<0.01)。A/S组术后1 d和3 d时海马ATP水平低于C组(P<0.01)。结论麻醉手术导致老年小鼠脑内能量代谢紊乱的机制可能与mTOR信号通路活化有关。

Objective To evaluate the relationship between energy metabolism disorders and mammalian target of rapamycin(mTOR)signaling pathway in elderly mice induced by anesthesia and surgery.Methods Sixty-four healthy male C57BL/6 mice aged 18 months were randomly divided into two groups(n=32),the control group(group the C)and the operation with anesthesia group(group the A/S).The Morris Water Maze test was performed on postoperative day 3.The levels of GLUT1,mTOR and phosphorylated mTOR(p-mTOR)were detected by Western blot,and the p-mTOR/mTOR ratio was calculated.The ATP concentration in hippocampus was detected by the ATP kit.The brain tissue was sectioned and stained with immunofluorescence on days 1 and 3 after operation.The expressions of GLUT1 and p-mTOR in hippocampus was observed.Results The incubation period of mice in the two groups decreased with the change of time,and the incubation period of mice in the A/S group was higher than that in the C group on the 6th day after operation(P<0.01),and no interaction existed between the two groups and each time points(P>0.05).The times of platform crossing and platform quadrant swimming time in the A/S group were lower than those in the C group on postoperative day 7(P<0.01).Compared with the C group,the expressions of GLUT1 were decreased and the expressions of p-mTOR were increased in the A/S group at days 1 and 3 after operation(P<0.01).Compared with the C group,the levels of GLUT1 in hippocampus of the A/S group were decreased and the p-mTOR/mTOR ratios were increased at days 1 and 3 after operation(P<0.01).The levels of ATP in the hippocampus of the A/S group were lower than those of the C group at days 1 and 3 after operation(P<0.01).Conclusion The mechanism of energy metabolism disorder in the brain of elderly mice induced by operation with anesthesia may be related to the activation of mTOR signaling pathway.