Apelin对急性局灶性脑缺血再灌注损伤大鼠脑神经细胞的保护作用

Neuroprotective effects of apelin after acute cerebral ischemia and reperfusion in rats

目的利用apelin在大鼠急性局灶性脑缺血再灌注早期进行干预处理,观察大脑神经细胞凋亡情况及脑组织抗氧化应激能力的变化。方法取成年雄性Wistar大鼠随机分成假手术对照(sham)组12只、缺血再灌注(I/R)组72只、缺血再灌注+apelin干预(I/R+AP)组72只。I/R组和I/R+AP组又根据灌注时间分为再灌注3、6、12、24、72、120h亚组,每亚组12只。I/R+AP组在再灌注早期(30min)用10-7 mol/L apelin(10μl)进行侧脑室注射给药干预处理。利用RT-PCR测定各组大鼠损伤侧大脑皮质caspase-3、caspase-12mRNA表达的变化;用流式细胞术检测各组大鼠大脑神经细胞凋亡率;用试剂盒测定脑组织丙二醛(MDA)含量、总谷胱甘肽过氧化物酶活性以及总抗氧化能力。结果 RT-PCR检测结果显示,与假手术组比较,I/R组和I/R+AP组caspase-3、caspase-12mRNA在损伤侧大脑皮质的表达升高;apelin干预可下调caspase-12mRNA的表达,而caspase-3mRNA的表达变化不明显。流式细胞术检测结果显示,apelin+AP组缺血区神经细胞凋亡率较I/R组降低(P<0.05),且随时间增加变明显。脑组织氧化应激功能检测结果显示,与假手术组比较,I/R组脑组织MDA含量升高(P<0.05),总谷胱甘肽过氧化物酶活性和总抗氧化能力降低(P<0.05);apelin干预后,MDA含量下降,总谷胱甘肽过氧化物酶活性和总抗氧化能力升高,与I/R组比较差异有统计学意义(P<0.05)。结论大鼠急性局灶性脑缺血再灌注后apelin的早期干预对脑神经细胞有一定的保护作用。

Objective To observe the neuron apoptosis and anti-oxidative stress function of cerebral tissues after acute cerebral ischemia/reperfusion （I/R） in rats treated with apelin in the early period of acute cerebral I/R. Methods Totally 156 male Wistar rats were randomly divided into 3 groups： sham group （n= 12）, ischemia reperfusion group （I/R group, n= 72） and ischemia reperfusion plus apelin group （I/R＋ AP group, n= 72）. The latter two groups were further divided into 6 subgroups according to reperfusion time （3, 6, 12, 24, 72, and 120 h groups, each group containing 12 rats）. Apelin （10 7 mol/L [10 tA]） was injected into the lateral ventricle in the early time of reperfusion （30 rain） in the I/R＋AP group. RT-PCR was used to observe the change of caspase-3 and caspase-12 mRNA expression in the injured side of cerebral cortex in each group, and flow cytometer was employed to detect the apoptosis rate of neurons. The content of malondialdehyde （MDA）, activity of glutathione peroxidase （GSH-Px）, and the total antioxidant capacity were also examined in the brain homogenate after I/R. Results The expression of caspase-3 mRNA and caspase-12 mRNA was increased in I/R and I/R＋AP groups compared with the sham group. Treatment with apelin down-regulated caspase-12 mRNA expression but had little influence on caspase-3 mRNA expression. The neuron apoptosis rate was significantly lower in I/R＋ AP group compared with the I/R group （P^0.05）, and the changes increased with time. Compared with the sham group, I/R group had significantly increased MDA content （P 〈0. 05） and significantly decreased GSH-Px activity and total antioxidant capacity （P〈0.05）. Compared with the I/R group, l/R＋ AP group had significantly increased GSH-Px activity and total antioxidant capacity and significantly decreased MDA content （P 〈 0. 05 ）.Conclusion Early intervention with apelin can protect the neurons in rats after acute cerebral I/R.