Effect Of EZH2 On Nrf2-ARE Antioxidant Stress Pathway In Antitubercular Drug-induced Liver Injury

Objective To investigate the regulatory effect of Enhancer of zeste homolog 2(EZH2)on the antioxidant stress pathway of Nrf2-ARE in the fruit flies of anti-tuberculosis drug-induced liver injury(ADLI).Methods The study was divided into two parts:(1)Population study: first,blood samples and clinical data were collected from initially treated patients with pulmonary tuberculosis,which were divided into ADLI group and non-ADLI group,with 84 cases in each group.The levels of EZH2,Nrf2,NQO1 and HO-1 were detected by ELISA.Finally,data differences between the two groups,differences in EZH2,Nrf2,NQO1 and HO-1 protein levels,and the correlation between EZH2 level and Nrf2-ARE pathway in the ADLI group were analyzed.(2)Animal experiment: 32 kunming mice were randomly divided into blank control group,model group,experimental group and negative control group.The mice were sacrificed and samples were collected after 5 days of gavage and transfection.Serum ALT and AST levels were detected by microplate assay,liver hiopathological changes were observed by HE staining,mRNA levels of EZH2,Nrf2,NQO1 and HO-1 were detected by real-time quantitative PCR,protein levels of EZH2,Nrf2,NQO1 and HO-1 were detected by western blot and ELISA,and levels of Nrf2 promoter region H3K27me3 in liver tissues of mice were detected by chromatin immunoprecipitation(Chip).Results(1)Population study: The serum EZH2 protein level of ADLI group was lower than that of non-ADLI group(P<0.05).Compared with the non-ADLI group,Nrf2,NQO1 and HO-1 protein levels in ADLI group all increased(all P<0.01),and EZH2 was negatively correlated with Nrf2,NQO1 and HO-1 in ADLI group(all P<0.01).(2)Animal experiments: compared with the blank control group,ALT and AST levels of mice in the model group increased,and ALT and AST levels of mice in the experimental group decreased compared with the model group(all P<0.05).The pathological results of the model group showed hepatocyte apoptosis and necrosis,and the degree of liver injury in the experimental group was improved.Compared with the blank control group,the mRNA level of EZH2 in the model group was decreased,and that of the experimental group was further decreased(all P<0.05).Compared with the blank control group,the mRNA levels of Nrf2,NQO1 and HO-1 were increased in the model group,and further increased in the experimental group(all P<0.05).The results of EZH2,Nrf2,NQO1 and HO-1 were consistent with the results of mRNA(all P<0.05).Chip experiment results showed that compared with the blank control group,the level of Nrf2 promoter region H3K27me3 was decreased in the model group,and further decreased in the experimental group(all P<0.05).Conclusions 1 EZH2 is down-regulated in ADLI.2 inhibition of EZH2 can up-regulate the expression level of Nrf2-ARE antioxidant stress pathway,thus improving the degree of liver injury.3 EZH2 may raise H3K27me3 in the Nrf2 promoter region to inhibit the expression of Nrf2,and then affect the liver injury process through the Nrf2-ARE antioxidant stress pathway.Figure7;Table7;Reference 124...