Lv Chengmei, Maharjan Surendra, Wang Qingqing, Sun Yongxin, Han Xu, Wang Shan, Mao Zhengchun, Xin Yanming, Zhang Bing
Cell Physiol Biochem. 2017;43(3):1273-1287. doi: 10.1159/000481840. Epub 2017 Oct 9.
BACKGROUND/AIMS: Alpha-lipoic acid (α-LA) has been demonstrated to be protective against cerebral ischemia injury. Herein, we investigate the neuroprotective effect and underlying mechanisms of α-LA.
In vivo study, α-LA was administered intravenously upon reperfusion of transient middle cerebral artery occlusion. Garcia score was used to evaluate neurologic recovery. Infarct volume was examined by TTC staining, and oxidative damage was evaluated by ELISA assay. In an in vitro study, neurons were pretreated with α-LA at different doses and then subjected to OGD. Lentiviral vectors were applied to knockdown nuclear factor-erythroid 2-related factor-2 (Nrf2) or heme oxygenase-1 (HO-1). Cell viability was measured using CCK8. Protein expression was evaluated using western blot, and immunofluorescence staining was assessed.
α-LA significantly reduced the infarct volume, brain edema, and oxidative damage and promoted neurologic recovery in rats. Pretreatment of α-LA caused an obvious increase in cell viability and a decrease in intracellular reactive oxygen species. Western blot analyses and immunofluorescence staining demonstrated a distinct increase in Nrf2 and HO-1 protein expression. Conversely, knockdown of Nrf2 or HO-1 resulted in the down-regulation of HO-1 protein and inhibited the neuroprotective effect of α-LA.
α-LA treatment is neuroprotective and promotes functional recovery after ischemic stroke by attenuating oxidative damage, which is partially mediated by the Nrf2/HO-1 pathway.
背景/目的:已证明α-硫辛酸(α-LA)对脑缺血损伤具有保护作用。在此,我们研究α-LA的神经保护作用及其潜在机制。
在体内研究中,于短暂性大脑中动脉闭塞再灌注时静脉注射α-LA。采用Garcia评分评估神经功能恢复情况。通过TTC染色检测梗死体积,采用ELISA法评估氧化损伤。在体外研究中,用不同剂量的α-LA预处理神经元,然后进行氧糖剥夺。应用慢病毒载体敲低核因子红细胞2相关因子2(Nrf2)或血红素加氧酶-1(HO-1)。使用CCK8检测细胞活力。采用蛋白质印迹法评估蛋白质表达,并进行免疫荧光染色评估。
α-LA显著减小大鼠梗死体积、减轻脑水肿和氧化损伤,并促进神经功能恢复。α-LA预处理可明显提高细胞活力并降低细胞内活性氧水平。蛋白质印迹分析和免疫荧光染色显示Nrf2和HO-1蛋白表达明显增加。相反,敲低Nrf2或HO-1导致HO-1蛋白下调,并抑制α-LA的神经保护作用。
α-LA治疗具有神经保护作用,通过减轻氧化损伤促进缺血性中风后的功能恢复,这部分是由Nrf2/HO-1途径介导的。