延龄草苷对脊髓损伤大鼠核因子E2相关因子2/抗氧化反应元件信号通路的影响

Effect of Trillin on Oxidative Stress and Nuclear Factor E2-related Factor 2/Antioxidant Response Element Pathway in Rats after Spinal Cord Injury

目的探索延龄草苷对大鼠脊髓损伤后核因子E2相关因子2(Nrf2)/抗氧化反应元件(ARE)通路及氧化应激反应的影响。方法雄性Sprague-Dawley大鼠108只,随机分为假手术组、模型组和延龄草苷组,每组36只,每组再分为1 d、3d和7d三个亚组,每个亚组12只。模型组和延龄草苷组采用改良Allen重物打击法制备髓损伤模型,假手术组不损伤脊髓。延龄草苷组每天给予延龄草苷200mg/kg灌胃,假手术组和模型组每天给予等量生理盐水,每天2次。术后1d、3d、7d进行BBB评分;术后7d,取损伤部位脊髓组织进行尼氏染色,观察形态学变化;ELISA检测脊髓内氧化应激因子丙二醛(MDA)和超氧化物歧化酶(SOD)的变化;术后1d、3 d、7 d,Western blotting分析检测脊髓组织内Nrf2、Kelch样ECH关联蛋白1(Keap1)、血红素加氧酶-1(HO-1)和NAD(P)H醌氧化还原酶-1(NQO1)的表达情况。结果与模型组相比,延龄草苷组BBB评分提高(P<0.05);脊髓结构较完整,神经元形态较正常,尼氏小体数量增多;脊髓组织内SOD活性提高(P<0.05),MDA含量降低(P<0.05);脊髓内抗氧化相关蛋白Nrf2、Keap1、HO-1和NQO1的表达均升高(P<0.05)。结论延龄草苷对大鼠脊髓损伤有保护作用,可能通过抑制组织内氧化应激反应改善运动功能。

Objective To explore the effect of trillin on oxidative stress response and nuclear factor E2-related factor 2/antioxidant response element(Nrf2/ARE)pathway in rats after spinal cord injury(SCI).Methods A total of 108 male Sprague-Dawley rats were randomly divided into sham group(n=36),model group(n=36)and trillin group(n=36),each group was divided into one day,three days and seven days subgroups,with twelve rats in each subgroup.The SCI model was established by modified Allen's heavy strike method in the model group and the trillin group,but no obvious injury in the sham group.The trillin group was given trillin 200 mg/kg every day,and the same amount of normal saline was given in the sham group and model group,twice a day.BBB score was performed one day,three days and seven days after modeling.Morphological changes were tested by Nissl's staining,and the changes of malonaldehyde(MDA)content and superoxide dismutase(SOD)activity were detected by ELISA seven days after modeling.The expression of Nrf2,Kelch like ECH associated protein 1(Keap1),NAD(P)H quinone oxidoreductase(NQO1)and haemoxygenase 1(HO-1)were detected by Western blotting one day,three days and seven days after modeling.Results Compared with the model group,BBB scores increased(P<0.05);the structure of spinal cord was more complete and the number of Nissl bodies increased;SOD activity increased(P<0.05)and MDA content decreased(P<0.05);the expression of Nrf2,Keap1,NQO1 and HO-1 increased(P<0.05)in the trillin group.Conclusion Trillin may play a protective role in spinal cord injury by inhibiting oxidative stress response and improving the motor function.