The current study aimed to explore the role of autophagy in cerebral ischemia–reperfusion injuries (CIRI) and elucidate the efficacy of liensinine treatment. An in vitro ischemia–reperfusion (I/R) neuronal cell model was established and pretreated with liensinine or rapamycin (RAPA). Cell proliferation and survival were detected using a cell counting kit-8 (CCK-8) assay, while cell damage and apoptosis were detected using the lactate dehydrogenase (LDH) leakage rate and flow cytometry. Autophagy activity was detected using monodansylcadaverine (MDC) staining. Thereafter, I/R models were established in vivo in rats and the presence of neurological deficits was examined. Hematoxylin–eosin (HE) and triphenyl tetrazolium chloride (TTC) staining was used to detect pathological damage in brain tissue and the volume ratio of the cerebral infarction. The levels of PI3K/AKT pathway-related proteins and autophagy-related proteins (mTOR, LC3, P62, and TSC2) were detected using Western blot. The findings showed that liensinine treatment increased cell viability, decreased cell injury and apoptosis, and inhibited autophagy. The addition of RAPA to promote autophagy inhibited cell viability and enhanced cell injury and apoptosis. The I/R rats in the model group exhibited deficient neurological function, while those in the liensinine treatment group showed restoration of normal neural function and reduction of the necrotic area and infarct volume ratio in the brain tissue. Furthermore, liensinine treatment also inhibited the PI3K/Akt pathway activity and autophagy. However, addition of RAPA reversed the effects of liensinine treatment and aggravated brain tissue injury. Therefore, liensinine can play a neuroprotective role in CIRI by inhibiting autophagy through regulation of the PI3K/Akt pathway.

目的 探究miR-21对缺血/再灌注后血脑屏障保护作用与机制.方法 采用线栓法构建并验证雄性SD大鼠脑缺血/再灌注模型.实验随机分为空白质粒组、miR-21-mimic组和miR-21-inhibitor组(n=6).利用Western Blot检测大鼠大脑皮层组织中Bax蛋白的表达变化,免疫荧光检测大脑皮层组织中自噬相关蛋白LC-3的分布情况,9.4T磁共振测量比较不同时间大鼠脑梗死体积.结果 Western Blot实验结果显示:与空白质粒组相比,给予miR-2l-mimic的大鼠脑组织中Bax蛋白与AQP4蛋白的表达显著降低(P<0.05),而给予miR-21 inhibitor的大鼠脑组织中Bax蛋白的表达升高(P<0.05);免疫荧光结果显示:与空白质粒组比较,miR-21-mimic组中自噬相关蛋白LC-3表达降低(P<0.05),而miR-21 inhibitor组中LC3蛋白的分布增加(P<0.05);核磁共振结果显示:与空白质质粒组比较,miR-21-mimic组的脑梗死体积最小(P<0.05).结论 miR-2l可能通过下调Bax蛋白的表达抑制细胞凋亡或通过抑制自噬保护血脑屏障,减少脑梗死体积;miR-21有望作为缺血/再灌注后血脑屏障治疗的靶点.

目的:探究miR-125a在脑卒中的作用及其分子机制,为miR-125a在脑缺血治疗中的应用提供理论基础.方法:收集正常和脑卒中患者的血浆,Realtime PCR检测miR-125a的表达水平,ROC曲线分析敏感性和特异性.Person相关性分析miR-125a表达水平与患者NIHSS评分和脑梗死体积的相关性.Realtime PCR检测MCAO模型大鼠脑皮质和血浆中miR-125a表达水平,并进行相关性分析.9.4T磁共振测量MCAO模型大鼠脑梗死体积.Realtime PCR和Western Blot法检测AQP4 mRNA和蛋白的表达水平.结果:研究一共收集到70例正常和50例缺血性脑卒中患者的血浆样本,两组在性别(x2=1.469,P=0.225)和年龄(Z=-0.208,P=0.835)上无差异.缺血性脑卒中患者血浆中miR-125a表达水平高于正常组(Z=-7.01,P=0.000).预后良好患者血浆中miR-125a表达水平低于预后不良患者(Z=-2.183,P=0.029).血浆中miR-125a表达水平在区分正常者和缺血性脑卒中患者的敏感性和特异性较好(ROC=0.876,P=0.000).血浆中miR-125a表达水平与患者NIHSS评分正相关(r=0.303,P=0.032),和脑梗死体积正相关性(r=0.399,P=0.004).MCAO大鼠脑皮质中miR-125a表达水平升高(t=8.918,P=0.000),血浆中miR-125a表达水平升高(t=4.928,P=0.000),脑皮质与血浆中miR-125a表达水平呈正相关(r=0.823,P=0.044).第3天时,sh-miR-125a组脑梗死体积小于NC组.sh-miR-125a组AQP4 mRNA和蛋白表达水平小于NC组.结论:血浆中miR-125a表达水平在区分正常和脑卒中患者具有较好的敏感性和特异性,抑制miR-125a表达会通过降低AQP4的表达,减少脑梗死体积,为miR-125a在诊断和治疗脑缺血中的应用提供了理论基础.