Wang Jue, Han Dong, Sun Miao, Feng Juan
Department of Neurology, Shengjing Hospital, Affiliated Hospital of China Medical University, No.36 Sanhao Street, Shenyang, 110004, China.
J Mol Neurosci. 2016 Apr;58(4):424-31. doi: 10.1007/s12031-016-0724-9. Epub 2016 Feb 6.
Remote ischemic perconditioning (RIPerC) and ischemic postconditioning (IPOC) are well-acknowledged neuroprotective procedures during ischemic injury. The present study established a combined RIPerC and IPOC (RIPerC + IPOC) model in rats and studied how it would regulate the autophagy process and affect HMGB1 levels in a rat model of middle cerebral artery occlusion (MCAO). Rats with MCAO were treated with RIPerC by fastening and release of the left hind limb to achieve 4 cycles of 5 min remote ischemia reperfusion, 40 min prior to cerebral reperfusion, and then treated with IPOC by exposing the cerebral middle artery to 3 cycles of 30 s reperfusion/30 s occlusion at the onset of cerebral reperfusion. Infarction volumes, neurological deficits, and pathological changes were assessed 24 h after ischemia. The autophagy activator rapamycin (RAP) and the autophagy inhibitor 3-methyladenine (3-MA) were administrated for further mechanism. The expression and location of HMGB1 and the autophagy-related proteins like LC3, Beclin1, and P62 as well as plasma HMGB1 levels were measured. Our results suggested that RIPerC + IPOC attenuated plasma HMGB1 levels to intensify its neuroprotective effect against cerebral ischemic reperfusion injury via inhibiting the autophagy process.
远程缺血预处理(RIPerC)和缺血后处理(IPOC)是缺血性损伤期间公认的神经保护程序。本研究在大鼠中建立了RIPerC和IPOC联合(RIPerC + IPOC)模型,并研究了其在大脑中动脉闭塞(MCAO)大鼠模型中如何调节自噬过程以及影响HMGB1水平。通过固定和松开左后肢对MCAO大鼠进行RIPerC处理,以实现4个周期的5分钟远程缺血再灌注,在脑再灌注前40分钟进行,然后在脑再灌注开始时通过将大脑中动脉暴露于3个周期的30秒再灌注/30秒闭塞进行IPOC处理。在缺血24小时后评估梗死体积、神经功能缺损和病理变化。给予自噬激活剂雷帕霉素(RAP)和自噬抑制剂3-甲基腺嘌呤(3-MA)以进一步研究机制。检测HMGB1以及自噬相关蛋白如LC3、Beclin1和P62的表达和定位以及血浆HMGB1水平。我们的结果表明,RIPerC + IPOC通过抑制自噬过程降低血浆HMGB1水平,以增强其对脑缺血再灌注损伤的神经保护作用。