丁苯酞通过激动cAMP/CREB/BDNF信号通路改善小鼠缺血再灌注后认知障碍的作用机制

Mechanism of butylphthalide activating cAMP/CREB/BDNF signaling to improve cognitive impairment after ischemia-reperfusion in mice

目的:研究丁苯酞通过激动cAMP/CREB/BDNF信号通路改善小鼠缺血再灌注后认知障碍的作用机制。方法:采用反复结扎双侧颈总动脉造成缺血再灌注损伤小鼠的认知障碍模型(VCI)。将小鼠分为假手术组、模型组、药物组,药物组分别采用5、10、20 mg/kg的丁苯酞(NBP)干预。Morris水迷宫实验检测小鼠认知能力,尼氏(Nissl)染色观察小鼠海马神经元的形态,比色法检测海马中超氧化物歧化酶(SOD)的活性、丙二醛(MDA)的水平以及一氧化氮(NO)的水平。Western blot法检测海马组织中环磷酸腺苷(cAMP)、磷酸化环磷酸腺苷反应原件结合蛋白(p-CREB)、脑源性神经营养因子(BDNF)的表达水平。结果:模型组小鼠认知功能下降,与假手术组比较差异具有统计学意义(P<0.05);模型组小鼠海马区组织中SOD活力下调,MDA和NO含量上调,与假手术组比较差异具有统计学意义(P<0.05)。Nissl染色显示模型组小鼠神经元细胞变性坏死且cAMP、CREB、BDNF蛋白表达受到抑制,与假手术组比较差异具有统计学意义(P<0.05)。NBP干预后,小鼠认知能力显著提高,与模型组比较差异具有统计学意义(P<0.05)。海马区SOD活性上调,MDA和NO水平下调,具有剂量依赖性,与模型组比较差异具有统计学意义(P<0.05)。cAMP、p-CREB、BDNF蛋白表达上调;Nissl染色显示,NBP干预后海马区神经元细胞凋亡减少。结论:NBP改善卒中后认知障碍的机制可能与激活cAMP/CREB/BDNF信号通路有关。

AIM:To study the mechanism of butylphthalide to improve the cognitive impairment after ischemia-reperfusion in mice by stimulating cAMP/CREB/BDNF signal and to provide support for the study of butylphthalide.METHODS:The cognitive impairment model(VCI)was induced by repeated ligation of bilateral common carotid arteries in mice with ischemia-reperfusion injury.The mice were divided into sham operation group,model group and drug group.The drug group was treated with 5,10,20 mg/kg butylphthalide(NBP).The Morris water maze test was used to detect the cognitive ability of mice.Nissl staining was used to observe the morphology of neurons in the hippocampus of mice.The activity of SOD,the level of malondialdehyde(MDA)and nitric oxide(NO)were detected by colorimetric method.The expression of cyclic adenosine phosphate(cAMP),phosphorylated cyclic phosphoric acid(p-CREB)and brain derived neurotrophic factor(BDNF)in the hippocampus were detected by Western blot.RESULTS:Compared with the sham operation group,the cognitive function of the model group was decreased(P﹤0.05),the SOD expression level in the hippocampus tissue of the model group was decreased,and the levels of MDA and NO were increased(P﹤0.05),and Nissl staining showed that the neuron cell degeneration and necrosis were found in the model group and the expression of cAMP/CREB/BDNF signal was inhibited(P﹤0.05).Compared with the model group,after NBP intervened,the cognitive ability of mice was significantly improved(P﹤0.05),the level of SOD in hippocampus was up-regulated,and the levels of MDA and NO were decreased in a dose-dependent manner(P﹤0.05).The cAMP/CREB/BDNF signal activated the expression of key proteins cAMP,p-CREB and BDNF increased.Nissl staining showed that the apoptosis of neurons in hippocampus was reduced after NBP intervention.CONCLUSION:NBP can activate cAMP/CREB/BDNF signal to improve cognitive function after ischemia and reperfusion,which is one of the mechanisms of butylphthalide improvement of cognitive impairment after stroke.