三氧化二砷对肉鸡原代肝细胞氧化应激和甲硫氨酸亚砜还原酶基因表达的影响

Effects of arsenic trioxide on the oxidative stress and expression of methionine sulfoxide reductases’ genes in chicken primary hepatocytes

为探究三氧化二砷（As2O3）对肉鸡原代肝细胞氧化应激和甲硫氨酸亚砜还原酶Msrs基因（MsrA、MsrB1、MsrB3）mRNA水平表达的影响,本研究将肉鸡原代肝细胞培养36 h后,随机将其分为对照组（0 mol/L As2O3）、低剂量组（0.5 mol/L As2O3）、中剂量组（1.0 mol/L As2O3、2.0 mol/L As2O3）、高剂量组（4.0 mol/L As2O3）、N-乙酰半胱氨酸组（1.0 mmol/L NAC）、合并应用NAC组（4.0 mol/L As2O3＋1.0 mmol/L NAC）,继续培养24 h后检测其抗氧化指标和Msrs基因mRNA水平的表达变化。结果显示：谷胱甘肽（GSH）含量在中剂量组、NAC组和合并应用NAC组显著升高（P〈0.05）;过氧化氢酶（CAT）含量在高剂量组显著升高（P〈0.05）;丙二醛（MDA）含量在低、中、高剂量组显著升高（P〈0.05）;超氧化物歧化酶（SOD）活性在低、中剂量组和合并应用NAC组显著升高（P〈0.05）,但在高剂量组显著降低（P〈0.05）。除了NAC组,其余各组Msrs基因mRNA的表达水平均显著降低（P〈0.05）。合并应用NAC组与高剂量组相比,GSH含量、SOD活性显著升高（P〈0.05）,CAT、MDA含量极显著降低（P〈0.01）。结果表明：高剂量As2O3可以导致原代肉鸡肝细胞氧化损伤,同时Msrs基因mRNA水平的表达有所降低,提示Msrs基因可能在As2O3引起的肝细胞氧化损伤修复中起重要作用,而NAC则可以缓解砷的细胞毒性。

In order to evaluate the effects of arsenic trioxide（As2O3）on the oxidative stress and mRNA expression level of methionine sulfoxide reductase（Msrs）genes in chicken primary hepatocytes,the primary hepatocytes were randomly divided into the control group（0 mol/L As2O3）, low-dose group（0.5 mol/L As2O3）, medium-dose groups（1.0 mol/L As2O3,2.0 mol/L As2O3）,high-dose group（4.0 mol/L As2O3）,As2O3＋N-acetyl cysteine（NAC）group（4.0 mol/L As2O3＋1.0 mmol/L NAC）after being cultured for 36 h and then continued to culture for 24 h.The antioxidant index and the mRNA expression of Msrs genes were measured.In result,levels of glutathione（GSH）were increased significantly in the mediu-dose groups,the NAC group and the As2O3＋NAC.Levels of catalase（CAT）were increased significantly in the high-dose gr-oup. Levels of malondialdehyde（MDA）were increased significantly in the low-dose group, the medium-dose group and the high-dose group.Activities of superoxide dismutase（SOD）were increased significantly in the low-dose group,the medium-dose group and the As2O3＋NAC group, but it was decreased significantly in the high-dose group. The mRNA expression of Msrs genes were increased significantly except the NAC group.The contents of GSH and the activity of SOD were increased significantly,and the contents of CAT and MDA were decreased significantly in the As2O3＋NAC group compared with the high-dose group.The results indicated that As2O3 induced oxidative injuries in chicken primary hepatocytes,and the mRNA expression of Msrs was reduced.It suggested that Msrs may play an important role in oxidative damage restoration caused by As2O3 in hepatocytes and NAC could relieve cytotoxicity of arsenic.