Objective: To explore the effect of picroside Ⅱ on the expression of mitochondrial voltage-dependent anion channel 1 (VDAC1) in rats after cerebral ischemiareperfusion. Methods: A total of 70 Wistar rats models with middle cerebral artery occlusionreperfusion (MCAO/R) were randomly divided into the sham group, model group, picroside (Picr) group, ruthenium red (RuR) group, RuR+ Picr group, Spermine (Sper) group, Sper+ Picr group (n=10 per group). Modified neurological severity scale (mNSS) was used to evaluated the neurobehavioral function, the expression of reactive oxygen species (ROS) in brain tissues were measured by enzyme-linked immunosorbent assay (ELISA), the morphology of brain tissues was observed by hematoxylin-eosin (HE) staining, the apoptotic cells were counted by terminal deoxynucleotidyl transferase dUTP nick end labeling assay (TUNEL), and the expressions of VDAC1 and endonuclease G (EndoG) were determined by immunohistochemical assay and Western blot. Results: Compared with the shame group, the mNSS scores (9.6±1.9), the expression of ROS[(47.6±2.7)U/ml], the apoptosis of neuron(23.8±2.8), and the expressions of VDAC1(0.94±0.06) and EndoG in cytoplasm (0.76±0.06) and nuclei(0.75±0.06)were enhanced in the model group (all P<0.05). The Picr group had obviously decreased mNSS scores (5.7±0.9), ROS expression[(35.6±2.2)U/ml], number of apoptotic cells (14.5±2.1), VDAC1 (0.63±0.06) and EndoG in cytoplasm (0.34±0.05) and nuclei (0.31±0.06)expressions compared to the model group (P<0.05). Conclusion: Picroside Ⅱ could attenuate cerebral I/R injury by down-regulating the expression of VDAC1 and inhibiting the EndoG release from mitochondria into cytoplasm.
目的： 研究胡黄连苷Ⅱ对脑缺血再灌注损伤后线粒体电压依赖性阴离子通道1(VDAC1)表达的影响和意义。 方法： 应用线栓法建立大鼠大脑中动脉闭塞(MCAO)模型，按随机数字表法将造模成功的70只大鼠分为假手术组、模型组、胡黄连苷组、VDAC1选择性抑制剂钌红组、钙红＋胡黄莲苷组、VDAC1选择性激动剂精胺组、精胺＋胡黄连苷组，每组10只。改良神经功能缺损评分(mNSS)评价动物神经行为功能；ELISA检测脑组织活性氧(ROS)含量；HE染色观察神经细胞形态；原位末端标记(TUNEL)检测神经细胞凋亡；免疫组化染色和Western印迹检测VDAC1和核酸内切酶(EndoG)表达水平。 结果： 与假手术组比较，模型组大鼠mNSS评分明显升高[(9.6±1.9)分]，ROS含量增加[(47.6±2.7)U/ml]，皮质区变性细胞(0.79±0.04)和凋亡细胞增加(23.8±2.8)，VDAC1(0.94±0.06)和EndoG[胞质(0.76±0.06)，胞核(0.75±0.06)]表达均显著增强(P<0.05)。与模型组比较，胡黄连苷组大鼠mNSS评分下降[(5.7±0.9)分]，ROS含量降低[(35.6±2.2)U/ml]，皮质区变性细胞(0.48±0.04)和凋亡细胞减少(14.5±2.1)，VDAC1(0.63±0.06)和EndoG[胞质(0.34±0.05)，胞核(0.31±0.06)]表达均显著降低(P<0.05)。 结论： 胡黄连苷Ⅱ可通过下调脑缺血再灌注后VDAC1表达而减少线粒体凋亡蛋白EndoG的释放，发挥神经保护作用。.
Keywords: Endonuclease G; Ischemia/reperfusion; Picroside Ⅱ; Rats; Voltage-dependent anion channel 1.