葛根素对缺氧缺血新生大鼠神经保护作用及其机制

Neuroprotective effect of puerarin after hypoxic-ischemic in neonatal and its mechanism

目的:观察葛根素(Pue)对缺氧缺血性脑损伤(HIBD)新生大鼠脑源性神经生长因子(BDNF),Bax,及半胱天冬酶-3表达及远期学习记忆能力的影响.方法:7d龄S D大鼠随机分为3组:葛根素组(Pue组)在缺氧缺血后注射葛根素50 mg/kg,1次/d,共7 d;对照组(Con组)给予同体积的的生理盐水;假手术组(Sham组)仅分离经总动脉,不给药.各组分别于1 wk后采用免疫组化方法检测各组BDNF,Bax,Caspase-3在海马区的表达,4 wk后水迷宫检测其远期学习记忆能力.结果:①术后1 wk海马区Pue组BDNF表达水平高于Con组(P<0.05),海马区Bax,Caspase-3表达水平低于Con组(P<0.05,P<0.01).②术后4 wk Morris水迷宫Pue组逃避潜伏期缩短明显快于Con组(P<0.05,P<0.01),穿过原平台次数及在目标象限游泳时间与总时间百分比Pue组明显多于Con组(P<0.05,P<0.01).结论:葛根素能减轻新生大鼠缺氧缺血引起的脑组织损伤,提高新生大鼠年长后的学习记忆能力.这种保护作用可能和葛根素增加海马区BD-NF的表达、降低Bax,Caspase-3在海马区的表达抑制海马区神经细胞的凋亡有关.

AIM：To investigate the effects of puerarin on the expression of BDNF,Bax,Caspase-3 in hippocampal cell and impact on learning and memory ability after hypoxia-ischemia brain injury in neonatal rats.METHODS：All SD rats（P7） were randomly divided into 3 groups：treatment with Puerarin group,control group,and sham group.Rats in Puerarin group and control received hypoxia-ischemia brain injury.Rats in Puerarin group were treated with Puerarin in doses of 50 mg/kg ip at 5 min after reoxygenation,once a day for 7 d in total.Rats in control group were given the same volume of saline.The rat pups of sham group were separated the right common carotid,but not ligated and they were not exposed to hypoxia.At 1 week after hypoxia,expression of BDNF,Bax,Caspase-3 were detected in the hippocampal region by immunohistochemistry.At 4 weeks after surgery,behavioral changes in the remaining rats were tested by Morris water maze.RESULTS：①One week later,the expression of BDNF in the Puerarin group was signif...更多icantly higher than that of the control group after hypoxic-ischemic（P〈0.05）;and the expression of Bax and Caspase-3 in the Puerarin group was lower than that of the control group（P〈0.05,P〈0.01）.②The average time of escape latency in Puerarin is much shorter than control group（P〈0.05,P〈0.01）,In addition,the frequency platform passing in the Puerarin group and the percentage of swimming time traveled in the previous target quadrant was significantly greater than the control group（P〈0.05,P〈0.01）.CONCLUSION：Puerarin may reduce brain injury and improve learning and memory in hypoxic-ischemic brain injury rats.This protection may be associated with increased BDNF levels and decreased pro-apoptoic protein（Bax）and Caspase-3. 还原