龙眼参多糖对大鼠局灶性脑缺血再灌注损伤细胞凋亡的影响

Effect of Longyanshen polysaccharide on cell apoptosis after focal cerebral ischemia reperfusion injury in rats

目的:研究龙眼参(LYS)多糖对局灶性脑缺血再灌注损伤大鼠细胞凋亡的影响。方法:180只Wistar性大鼠随机分为脑缺血再灌注组,LYS多糖高、中、低剂量组,阳性对照组,假手术组。给药组术前连续灌胃7 d,于末次给药60min后行手术,采用大脑中动脉局灶性缺血再灌注模型,观察缺血2 h再灌注24 h后,LYS多糖对各组大鼠脑梗死体积、脑含水量及脑组织中上Bcl-2、Bax蛋白表达的影响,并在光镜下观察各组大鼠皮层区细胞损伤程度。结果:与脑缺血再灌注模型组相比,LYS多糖能够降低大鼠脑梗死体积和脑含水量,增加脑组织中Bcl-2蛋白表达,减少Bax蛋白表达(P<0.01或P<0.05),并减轻皮层神经细胞水肿。结论:龙眼参多糖对大鼠急性脑缺血再灌注损伤具有保护作用.其机制可能与其上调Bcl-2蛋白表达.下调Bax蛋白表达,通过调节凋亡相关基因表达抑制凋亡有关。

OBJECTIVE To investigate the effect of Longyanshen （LYS） polysaccharide on cell apoptosis due to focal cerebral ischemia/reperfusion（I/R） injury in rats. METttODS 180 Wistar male rats were randomly divided into I/R group, shamoperated group, high-, medium-and low-dose of LYS polysaccharide groups （0. 6, 0. 3 and 0. 15 g. kg·d^- 1 respectively）, and nimodipine （Nim） group. The animals were intragastrically administered with drugs for 7 days. The operation was performed to induce the middle cerebral artery occlusion （MCAO） model in rats at 60 minutes after the end administration of drug. After ischemia for 2 hours and reperfusion for 24 hours in each model rats, the influences of LYS polysaccharide on the water content of brain, the infarct volume, the expressions of Bcl-2 and Bax were investigated; the morphological changes of rat cerebral cortical neurons （HE staining） were observed under optical microscope. RESULTS Compared with I/R group, LYS polysaccharide could obviously reduce the water content of brain and the infarct volume, increase the expression of Bcl-2, decrease the expression of Bax （P〈0. 01 or P〈0. 05）, and lessened the neuronal edema. CONCLUSION LYS polysaccharide has protective effect on cerebral ischemia/reperfusion injury, the mechanism of which may be related to up-regulating Bcl-2 and down-regulating Bax, and reducing apoptosis of cells.