肝细胞核因子FOXA2通过抑制氧化应激减轻小鼠肝纤维化

Hepatocyte nuclear factor FOXA2 attenuates hepatic fibrosis in mice by inhibiting oxidative stress

目的探究调控肝细胞叉头框转录因子A2(forkhead box transcription factor A2,FOXA2)表达对肝纤维化小鼠体内氧化应激(oxidative stress,OS)指标的影响。方法通过对小鼠进行腹腔注射CCl4建立肝纤维化模型,选取FOXA2^(loxP/lox)P雄性小鼠18只,随机分为正常组、对照组和FOXA2^(H-KO)组,每组6只,造模后FOXA2^(H-KO)组基于LoxP-Cre重组系统经尾静脉注射腺相关病毒AAV8-TBG-Cre,对照组注射对照病毒AAV8-TBG;另取18只C57BL/6J雄性小鼠随机分为3组,每组6只,分别为正常组、对照组和FOXA2组,造模后FOXA2组经尾静脉注射病毒AAV8-TBG-FOXA2,对照组小鼠注射AAV8-TBG病毒。通过qPCR检测各组小鼠肝组织中TGF-β1 mRNA变化,丙二醛(malondialdehyde,MDA)比色法检测肝组织中MDA的含量,Western blotting法检测各组肝脏中3-硝基酪氨酸(3-nitrotyrosine,3-NT)蛋白变化。结果与正常组相比,CCl4造模可显著增加肝组织中TGF-β1 mRNA的表达,并导致肝组织中MDA、3-NT水平升高,诱发小鼠体内的OS;敲除肝细胞FOXA2后可促进小鼠纤维化肝组织中TGF-β1、MDA及3-NT水平进一步升高,差异有统计学意义(P<0.01);而上调肝细胞FOXA2表达可明显减少纤维化肝组织中TGF-β1表达(P<0.05),并显著抑制OS相关指标(MDA、3-NT)升高(P<0.01)。结论调控肝细胞FOXA2可影响肝纤维化小鼠体内的OS水平,FOXA2可能通过抑制OS发挥抗纤维化作用。

Objective To investigate the effect of forkhead box transcription factor A2(FOXA2)on oxidative stress(OS)in fibrotic livers induced by CCl4in mice.Methods The mice were recruited to establish a kind of liver fibrosis animal model by injecting with CCl4intraperitoneally.Eighteen FOXA2^(loxP/lox)Pmale mice were randomly divided into normal group,control group and FOXA2^(H-KO)group,with 6 mice in each group.The mice in FOXA2^(H-KO)group were injected with the AAV8-TBG-Cre,while the mice in control group were injected with control vector AAV8-TBG by tail vein injection.Eighteen C57BL/6J male mice were divided into normal group,control group and FOXA2 group(n=6).After treating with CCl4,the mice in FOXA2 group were injected with AAV8-TBG-FOXA2,while the control mice were injected with AAV8-TBG.The mRNA expressions of TGF-β1 were measured by qPCR.The levels of malondialdehyde(MDA)in liver tissues were detected by corresponding assay kits.Western blotting was performed to determine the protein of 3-nitrotyrosine(3-NT).Results Compared with normal group,CCl4treatment could increase the mRNA of TGF-β1 and the indicators of OS(MDA and 3-NT)in the fibrotic livers of control group.Knockout FOXA2 in hepatocytes could further aggravate significantly the increasing of TGF-β1,MDA and 3-NT in fibrotic livers(P<0.01).While upregulation of FOXA2 in hepatocytes remarkably inhibited the TGF-β1 mRNA(P<0.05)and OS-related indexes(MDA and 3-NT)(P<0.01)in fibrotic livers contrasted with the control mice.Conclusion Modulating FOXA2 in hepatocytes influences OS in hepatic fibrosis of mice.FOXA2 has therapeutic potential for treating hepatic fibrosis via inhibiting OS.