黄芪甲苷对脑缺血再灌注后血脑屏障的保护作用及IL-1β含量、MMP-9蛋白表达的影响

Protective effects of astragaloside IV on blood-brain barrier and the content of IL-1β and expression of MMP-9 protein after cerebral ischemic reperfusion

目的探讨黄芪甲苷对大鼠脑缺血再灌注后血脑屏障的保护作用及其机制。方法将SD大鼠72只随机等分为4组:假手术组、生理盐水对照组、小剂量黄芪甲苷治疗组(10 mg/kg)和大剂量黄芪甲苷治疗组(20 mg/kg),采用分光光度计法、酶联免疫吸附法及免疫组化法分别检测各组大鼠脑组织伊文氏蓝、IL-1β含量及MMP-9蛋白的表达水平。结果与假手术组相比,生理盐水对照组脑组织伊文氏蓝含量明显增多、IL-1β含量显著增高、MMP-9蛋白的表达明显增强(P<0.01);与生理盐水对照组相比,小剂量黄芪甲苷治疗组及大剂量黄芪甲苷治疗组脑组织伊文氏蓝含量均显著减少、IL-1β含量明显降低、MMP-9蛋白表达明显减弱(P<0.05);小剂量黄芪甲苷治疗组与大剂量黄芪甲苷治疗组相比,伊文氏蓝、IL-1β含量及MMP-9蛋白表达无显著差异(P>0.05)。结论黄芪甲苷对脑缺血再灌注后血脑屏障具有保护作用,这可能与其下调IL-1β含量、抑制MMP-9蛋白的表达有关。

Objective To investigate the protective effects of astragaloside Ⅳ on blood-brain barrier and the content of IL-1β, expression of MMP-9 protein after cerebral ischemic reperfusion. Methods 72 SD rats were divided randomly into four groups： sham-operated group, normal- saline contral group, group treated by low dose of astragaloside Ⅳ（10 mg/kg）, group treated by high dose of astragaloside Ⅳ（20 mg/kg）. Evans Blue（EB） leakage, the content of IL-1β, expression of MMP-9 protein were respectively detected by spectro- photometry, ELISA and immunohistochemistry. Results Compared with sham-operated group, EB leakage, the content of IL-1βand expression of MMP-9 protein were higher in normal- saline contral group （P〈0. 01）. Compared with normal saline contral group, EB leakage, the content of IL-1β and expression of MMP-9 protein were lower in group treated by low dose of astragaloside Ⅳ and group treated by high dose of astragaloside 1V （P〈0. 05）. There was no statistical difference between group treated by low dose of astragaloside Ⅳ and group treated by high dose of astragaloside Ⅳ （P〉0. 05）. Conclusion Astragaloside Ⅳ could have protective effects on blood-brain barrier after cerebral ischemic reperfusion. Its mechanisms may be associated with down- regulation of the content of IL-1β and expression of MMP-9 protein.