黄芪注射液抑制糖尿病大鼠海马神经元凋亡的机制研究

目的]探讨黄芪注射液对糖尿病模型大鼠认知功能的影响及其作用机制。方法]40只雄性SD大鼠,除空白组(n=10)外腹腔注射链脲佐菌素(60 mg/kg)复制Ⅰ型糖尿病大鼠模型,随机分为模型组和黄芪注射液组(1.6 mg/kg),给药10周。以Morris水迷宫法进行学习记忆功能测试,随即处死大鼠分离血清及脑组织,分别测定空腹血糖、空腹胰岛素水平和乙酰胆碱酯酶含量,RT-PCR法测定海马Bcl-2及Bax mRNA表达情况,免疫蛋白印迹法(Western blot)测定海马乙酰胆碱酯酶和Caspase-3的蛋白表达及免疫组化法观察海马各区Caspase-3蛋白的阳性表达情况。结果]黄芪注射液能显著提高糖尿病脑病大鼠学习记忆能力,降低糖尿病大鼠空腹血糖水平及AchE含量,升高血清胰岛素水平,减少海马AchE及Caspase-3蛋白的表达,升高海马抗凋亡基因Bcl-2的表达,降低促凋亡基因Bax的表达。结论]黄芪注射液能够显著改善糖尿病大鼠学习记忆功能,其作用机制可能与减少AchE含量、抑制神经细胞凋亡有关。

Study on the mechanism of the inhibitory action of Huangqi injection on apoptosis of hippocampal neurons in diabetic encephalopathy rats

Objective] To explore the effects of Huangqi injection on learning and memory abilities in diabetic rats and its mechanism research.Methods] Forty male SD rats, except the blank group(n=10),were intraperitoneal injected Streptozotocin (60 mg/kg) to establish type 1 diabetic rats, the modeled rats were equally and randomly divided into the model group and Huangqi injection group. All drugs were administrated for 10 weeks. The behavior test were performed on the Morris water maze method, and then the rats were executed for blood and brain sampling. Blood glucose, insulin and acetylcholinesterase level were detected. The expression of Bcl-2 and Bax in the hippocampus was examined by quantitative real-time PCR. The method of Western blotting was used to measure the expression of AchE. The expression of Caspase-3 in the hippocampus nerve cells was examined immunohistochemistry.Results] Huangqi injection obviously improved the learning and memory abilities of diabetic encephalopathy rats, reduced blood glucose and AchE level and incresed the insulin level. The expression of AchE and Caspase-3 protein were obviously reduced in the hippocampus of rats. The anti-apoptosis gene Bcl-2 mRNA epression was increased while the apoptosis Bax mRNA expression was decreased in hippocampal area in Huangqi injection group.Conclusion] Huangqi Injection obviously improved the learning and memory abilities of diabetic rats, its mechanism may be related to reduce AchE level, inhibit neuronal apoptosis.