丹龙醒脑方对脑缺血再灌注大鼠侧脑室室管膜下区神经干细胞增殖与c-myc、c-jun表达的影响

Effects of Danlong Xingnao Formula on Proliferation of Neural Stem Cells in SVZ and Expressions of c-jun and c-myc in Cerebral Ischemia Reperfusion Rats

目的探讨丹龙醒脑方对局灶性脑缺血再灌注大鼠侧脑室室管膜下区(SVZ)神经干细胞(NSCs)增殖与c-myc、c-jun表达的关系。方法采用线栓法制备大脑中动脉栓塞局灶性脑缺血再灌注模型。150只雄性SD大鼠随机分为假手术组、模型组和丹龙醒脑方小、中、大剂量组。于再灌注24 h后,丹龙醒脑方各剂量组予相应剂量药液灌胃,模型组和假手术组予等体积蒸馏水灌胃。1次/d,连续7 d。再灌注1、3、7 d采用m-NSS法进行神经功能缺损评分,再灌注7 d取缺血侧SVZ脑组织,采用Brdu免疫组化检测NSCs增殖,RT-q PCR、Western blot分别检测c-jun、c-myc m RNA和蛋白的表达。结果与假手术组比较,其余各组神经功能缺损评分明显升高(P<0.01);再灌注3、7 d,与模型组比较,丹龙醒脑方各剂量组神经功能缺损评分明显降低(P<0.01)。与假手术组比较,其余各组Brdu阳性细胞率明显升高;与模型组比较,丹龙醒脑方各剂量组Brdu阳性细胞率亦明显升高(P<0.01)。丹龙醒脑方各剂量组较假手术组、模型组c-jun、c-myc蛋白及m RNA表达均明显增强(P<0.05,P<0.01)。结论丹龙醒脑方能改善脑缺血后神经功能,促进SVZ NSCs增殖,其机制可能与增强c-jun和c-myc表达及延长表达持续时间有关。

Objective To study the relationship of proliferation of neural stem cells (NSCs) in SVZ and the expressions of c-jun and c-myc in rats with middle cerebral artery occlusion/reperfusion (MCAO/R) injury model administrated byDanlong XingnaoFormula.Methods The focal cerebral ischemia reperfusion injury models were prepared by longa method. Totally 150 male SD rats were randomly divided into sham-operation group, cerebral model group,Danlong XingnaoFormula low-, medium-, and high-dose groups. The treatment groups were given corresponding dose ofDanlong XingnaoFormula, while the sham-operation group and model group were given the same amount of distilled water 24 h after modeling by gavage, once a day, 7 days in a row. 1 d, 3 d and 7 d after reperfusion, modified Neurological Severity Scores (m-NSS) was used to grade neurologic impairment. 7 d after reperfusion taken to the SVZ brain tissue of ischemia side, Brdu immunohistochemical method was used to record the BrdU positive cells number. The hippocampal c-jun, c-myc mRNA and protein expressions were determined respectively by RT-qPCR method and Western blot method.Results Grades of neurologic impairment in others groups were improved obviously than sham-operation group (P<0.01); 3 d, and 7 d after reperfusion, grades of neurologic impairment inDanlong XingnaoFormula groups were obviously lower compared with model group (P<0.05,P<0.01). Brdu positive cell rates in others groups increased obviously compared with sham-operation group; Compared with model group, Brdu positive cell rates inDanlong XingnaoFormula groups increased obviously (P<0.01). The expressions of c-jun and c-myc protein and mRNA inDanlong XingnaoFormula groups improved obviously than sham-operation group and model group (P<0.01).ConclusionDanlong Xingnao Formula can improve the neural function after cerebral ischemia and stimulate the proliferation of NSCs, and the mechanism may be related to activating the expression of c-jun and c-myc and extending the duration.