菟丝子黄酮对大鼠脑缺血再灌注损伤后细胞凋亡及Bcl-2、Bax、Caspase-3表达的影响

Effect of flavonoids from Cuscuta chinensis on apoptosis and expression of Bcl-2,Bax and Caspase-3 in rats with cerebral ischemia-reperfusion injury

目的:观察菟丝子黄酮对大鼠脑缺血再灌注损伤细胞凋亡及相关基因表达的影响。方法:成年雄性SD大鼠80只,随机分为假手术组、模型组、菟丝子黄酮50 mg/kg、100 mg/kg剂量组、尼莫地平组(12 mg/kg),采用颈内动脉线栓法阻断大脑中动脉制备局灶性脑缺血再灌注模型,Longa法进行神经功能缺失症状评分,TUNEL法检测细胞凋亡,免疫组化法检测Bcl-2和Bax蛋白表达,计算Bcl-2/Bax值,Western Blot法检测Caspase-3蛋白表达。结果:与模型组比较,菟丝子黄酮治疗组大鼠神经功能评分明显降低,缺血侧大脑皮质细胞凋亡程度减轻,且均以100 mg/kg剂量组较为明显,免疫组化检测显示Bcl-2蛋白表达增加而Bax蛋白表达减少,Western blot检测显示Caspase-3蛋白表达明显减少。结论:菟丝子黄酮对大鼠脑缺血再灌注损伤具有一定的保护作用,其机制可能是通过下调Bax和Caspase-3,上调Bcl-2蛋白的表达来抑制细胞凋亡的发生。

Objective： To study the effect of flavonoids from Cuscuta chinensis on the expression of apoptosis-related factors in rat brain with cerebral ischemia-reperfusion. Method： Eighty male adult SD rats were randomly assigned into five groups： sham operation group,model group,50 mg / kg and 100 mg / kg flavonoids from Cuscuta chinensis and Nimodipine group（ 12 mg / kg）. Cerebral ischemia-reperfusion injury model of middle cerebral artery occlusion was induced by thread occlusion method of internal carotid. Neurological functuion deficits were evaluated by Longa test scale. Using TUNEL to detect apoptosis. The protein expression of Bcl-2 and Bax were measured by immunohistochemistry,the ratios of Bcl-2 and Bax were calculated. The expressions of caspase-3 protein were determined by Western blotting. Results： Compared with model group,neurological deficiency scores were lower and the degree of apoptosis was lessened in the group of flavonoids from Cuscuta chinensis,and most significantly in 100 mg / kg group. The expression of Bcl-2 was increased and Bax was decreased. The expression of Caspase-3 protein was decreased. Conclusion： Flavonoids from Cuscuta chinensis could protect cerebral ischemia reperfusion injury by decreasing the protein expression of Bax and Caspase-3 and increasing the protein expression of Bcl-2 to inhibit cell apoptosis.