甘草酸对大鼠肝星状细胞氧化应激抑制作用的机制研究

摘要

目的 探讨甘草酸对大鼠肝星状细胞(HSC)的氧化应激及核转录因子E2相关因子2(Nrf2)/血红素加氧酶(HO)-1信号通路的影响.方法 体外培养HSC细胞,将细胞分为5组:空白对照组、次氮基三乙酸铁(Fe-NTA)处理组、Fe-NTA+5 μmol/L甘草酸组、Fe-NTA+10 μmol/L甘草酸组及Fe-NTA+20 μmol/L甘草酸组;给药24 h后收集细胞,采用相关试剂盒检测HSC细胞中丙二醛(MDA)、一氧化氮(NO)、谷胱甘肽(GSH)的含量及超氧化物歧化酶(SOD)的活性;RT-PCR和Western blot方法分别检测Nrf2和HO-1 mRNA及蛋白表达水平.结果 Fe-NTA处理组中MDA、NO含量明显升高,而GSH水平显著降低,SOD酶活性也显著降低;而甘草酸处理的3组细胞中MDA、NO含量显著降低,GSH水平显著升高,SOD酶活性也显著升高,差异均有统计学意义(P<0.05).Fe-NTA处理组中Nrf2和HO-1mRNA及蛋白表达水平与空白对照组比较显著降低,而甘草酸处理的3组细胞中Nrf2和HO-1mRNA及蛋白表达水平相对于Fe-NTA处理组显著上调,差异均有统计学意义(P<0.05).结论 甘草酸有抗HSC细胞氧化应激损伤的作用,其作用机制可能与激活Nrf2/HO-1信号通路有关.%Objective To investigate the effect of glycyrrhizic acid (GA) on oxidative stress and the Nrf2/HO-1 signaling in rat hepatic stellate cells (HSCs).Methods HSCs were cultured in vitro and divided into five groups,including the control group,Fe-NTA group,Fe-NTA+5 μmol/L GA group,Fe-NTA+10 μmol/L GA group and Fe-NTA+20 μmol/L GA group.The levels of MDA,NO,GSH and the activity of SOD were measured.The expression levels of Nrf2 and HO-1 mRNA and proteins were analyzed using RT-PCR and Western blot.Results Compared with the control group,the levels of MDA and NO in HSCs were increased but GSH levels and SOD activities were decreased in Fe-NTA group.After treatment with different concentrations of GA,the levels of MDA and NO were significantly decreased but GSH levels and SOD activities were increased.The expression of Nrf2 and HO-1 in HSCs treated with GA was obviously enhanced compared with Fe-NTA group (P<0.05).Conclusion GA protects HSCs against oxidative stress injury,which may be related to activation of the Nrf2/HO-1 signaling pathway.