灯盏花素联合丙泊酚对脑缺血再灌注损伤大鼠的神经保护作用及Nrf2/HO-1通路的影响

Neuroprotective Effect of Breviscapine Combined with Propofol on Cerebral Ischemia-reperfusion Injury in Rats and Its Influence on Nrf2/HO-1 Pathway

目的:探讨灯盏花素联合丙泊酚对脑缺血再灌注损伤大鼠的神经保护作用及NF-E2相关因子/血红素加氧酶-1(Nrf2/HO-1)通路的影响。方法:将100只SD大鼠分为5组:对照组、模型组、灯盏花素组(10 mg·kg-1)、丙泊酚组(10 mg·kg-1)、联合组(10 mg·kg-1灯盏花素+10 mg·kg-1丙泊酚),每组20只。造模成功后腹腔注射给药,对照组和模型组给予等体积生理盐水,qd,连续4周。实验结束后,对大鼠认知功能进行评价,观察各组大鼠海马组织病理改变;检测大鼠海马组织中Nrf2、HO-1 mRNA、蛋白水平以及丙二醛(MDA)、一氧化氮(NO)、超氧化物歧化酶(SOD)蛋白表达水平。结果:对照组海马区神经元细胞完整,结构正常,染色清晰,核呈卵圆形位于中央;模型组海马区可见大量坏死神经元,且细胞脱失现象明显,细胞核固缩;灯盏花素组、丙泊酚组坏死神经元细胞减少,但神经元疏松紊乱,细胞核固缩,脱失现象明显;联合组海马区见少量坏死神经元细胞,且神经元细胞结构较为完整,神经元细胞核呈卵圆形位于中央,分布均匀。与对照组比较,模型组逃避潜伏期、NRF2、HO-1 mRNA、蛋白以及MDA、NO表达水平升高(P<0.05),经过原平台位置的次数、原平台象限留的时间、SOD表达水平降低(P<0.05);与模型组比较,灯盏花素组、丙泊酚组、联合组逃避潜伏期、NRF2、HO-1 mRNA、蛋白以及MDA、NO表达水平降低(P<0.05),经过原平台位置的次数、原平台象限留的时间、SOD表达水平升高(P<0.05);与灯盏花素组和丙泊酚组比较,联合组逃避潜伏期、NRF2、HO-1 mRNA、蛋白以及MDA、NO表达水平降低(P<0.05),经过原平台位置的次数、原平台象限留的时间、SOD表达水平升高(P<0.05)。结论:灯盏花素联合丙泊酚能减轻脑缺血再灌注损伤大鼠认知功能及海马神经元损伤程度,其机制为灯盏花素联合丙泊酚抑制Nrf2、HO-1 mRNA、蛋白的表达水平激活抗氧化途径,进而对脑缺血再灌注损伤大鼠的神经起到保护作用有关。

Objective:To investigate the neuroprotective effect of breviscapine combined with propofol on cerebral ischemia-reperfusion injury in rats and its influence on Nrf2/HO-1 pathway.Methods:Totally 100 SD rats were divided into 5 groups:the control group,the model group,breviscapine group(10 mg·kg-1),propofol group(10 mg·kg-1)and the combination group(10 mg·kg-1 breviscapine+10 mg·kg-1 propofol)with 20 rats in each group.After the successful establishment of model,the rats were administered intraperitoneally,and the control group and the model group were given saline with equal volume once a day for 4 weeks.At the end of the experiment,the cognitive function,the mRNA and protein expression levels of Nrf2 and HO-1 as well as the levels of malondialdehyde(MDA),nitric oxide(NO)and superoxide dismutase(SOD)in hippocampus were detected.The pathological changes in hippocampus of rats were observed in each group.Results:In the control group,the neurons in hippocampus were intact,the structure was normal,the staining was clear,and the nucleus was located in the center of the oval;in the model group,a large number of necrotic neurons were observed in hippocampus,and the cell loss was obvious,and the nucleus was pyknosis;in breviscapine group and propofol group,the necrotic neurons were reduced,while the cell nucleus was pyknosis and the loss was obvious.The hippocampus of the combination group showed a small number of necrotic neurons,and the neuronal cell structure was relatively complete,the neuron nucleus was oval and centrally located with even distribution.Compared with those in the control group,in the model group,the escape latency,the mRNA and protein expression levels of Nrf2 and HO-1,and the levels of MDA and NO in the model group increased(P<0.05),while the number of times passing through the original platform position,the time remaining in the original platform quadrant and the levels of SOD decreased(P<0.05).Compared with those in the model group,the escape latency,the mRNA and protein expression levels of Nrf2 and HO-1,and the levels of MDA and NO in the other three groups decreased(P<0.05),while the number of times passing through the original platform position,the time remaining in the original platform quadrant and the levels of SOD increased(P<0.05).Compared with those in breviscapine group and propofol group,the mRNA and protein expression levels of Nrf2 and HO-1,and the levels of MDA and NO in the combination group decreased(P<0.05),while the number of times passing through the original platform position,the time remaining in the original platform quadrant and the levels of SOD increased(P<0.05).Conclusion:Breviscapine combined with propofol can alleviate the cognitive function and hippocampal neuronal damage in rats with cerebral ischemia-reperfusion injury,and its mechanism is related to the inhibition of mRNA and protein expression levels of Nrf2 and HO-1,thus protecting the neurons of rats with cerebral ischemia-reperfusion injury.