GPX-1在大鼠肝缺血再灌注损伤模型的表达变化

Expression change of GPX-1 in hepatic ischemia-reperfusion injury rat model

目的观察谷胱甘肽过氧化物酶1(glutathione peroxidase 1,GPX-1)在大鼠肝缺血再灌注损伤(hepatic ischemia-reperfusion injury,HIRI)模型的表达变化,探讨GPX-1在清除过氧化物、降低缺血再灌注诱发的过氧化损伤中的作用。方法夹闭大鼠肝中、右叶肝蒂30min,建立大鼠HIRI模型;肝中、右叶再灌注6h后取血和肝脏。观察血清丙氨酸转氨酶(alanine aminotransferase,ALT)活性变化,采用速率法测定;HE染色法观察大鼠肝脏形态结构变化;观察肝组织过氧化氢(hydrogen peroxide,H_2O_2)和丙二醛(malondialdehyde,MDA)含量变化,分别采用钼酸比色法和硫代巴比妥酸比色法测定;GPX-1的mRNA表达水平和蛋白表达水平分别采用RT-PCR和Western blotting法测定;对GPX-1表达水平与MDA含量、GPX-1表达水平与H_2O_2含量分别进行相关性分析。结果 HIRI模型组大鼠肝组织形态结构受损明显,肝组织内H_2O_2和MDA含量均升高,血清ALT活性升高;肝组织内GPX-1mRNA表达水平和蛋白表达水平均明显增强,并与肝组织内MDA含量、H_2O_2含量呈正相关关系。结论大鼠肝缺血再灌注后,肝组织遭受过氧化损伤;抗氧化酶GPX-1表达升高可减轻过氧化损伤。

Objective To observe the expression change of glutathione peroxidase-1(GPX-1)in rats of hepatic ischemia-reperfusion injury(HIRI)model and investigate the role of GPX-1in scavenging peroxide and reducing peroxidative injury induced by ischemia and reperfusion.Methods The HIRI model of rats was established by blocking the hepatic pedicle of the right and middle lobes for30mins.The blood and liver were taken after6hours of reperfusion.The activity of serum ALT was detected with rate method,the changes of liver morphology and structure in rats was observed by HE staining,the malondialdehyde(MDA)and hydrogen peroxide(H2O2)content in liver were determined by Thiobarbituric acid colorimetric method,and Molybdate colorimetric method respectively.The GPX-1mRNA and protein expression level were evaluated by RT-PCR and Western blotting respectively,the correlation between the GPX-1expression level and the MDA content,between the GPX-1expression level and the H2O2content were analyzed.Results Compared with the rats of control group,the morphological structure of liver of HIRI group was significantly damaged,the serum ALT activity,the content of MDA and H2O2in the liver of HIRI model were significantly increased,the mRNA and protein expression level of GPX-1in liver were also significantly enhanced,There were positive correlation between GPX-1mRNA and MDA,between GPX-1pretein and MDA,between GPX-1mRNA and H2O2,between GPX-1pretein and H2O2.Conclusion Ischemia and reperfusion causes liver tissue to be in oxidative stress and been subjected to peroxidative damage.Antioxidant enzymes GPX-1may play an antioxidant stress role by scavenging peroxides during the process,and reduce hepatic peroxidative injury induced by ischemia-reperfusion.