Effects of Nrf2 mRNA and Keapl mRNA expressions on arsenism liver injury caused by coal-burning

ObjectiveTo invesigate the effects of transcriptional expressions of nuclear factor-erythroid 2-related factor 2 (Nrf2)and Kelch-like ECH-associated protein 1(Keapl)on the development of liver injury in endemic arsenism caused by coal-burning.MethodsTotally 133 residents with arsenic exposure were selected as arsenic exposure groups(including the normal group from endemic area,no obvious hepatopathy group,mild,moderate,and severe hepatopathy group)from the area with endemic arsenism in Guizhou province.Another 34 healthy residents were selected as the control group.The mRNA expressions of Nrf2 and Keapl were detected with real-time fluorescence quantitative PCR.Activities of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),thioredoxin reductase(TrxR),and malondialdehyde(MDA)content were detected with chemical methods.ResultsThe mRNA relative expressions of Nrf2 were 0.650 5(0.502 2-1.252 2), 0.690 4(0.602 7-1.040 5),0.877 8(0.611 3-1.656 2),1.283 4(0.761 1-2.765 9),and 1.393 5(0.824 3-3.098 3)for control group,normal group from the endemic area,no obvious hepatopathy group,mild,and moderate-severe hepatopathy group and the mRNA relative expressions of Keapl for the 5 groups were 1.569 1(1.135 8-3.981 4),1.451 0 (1.123 7-3.015 2),1.3954(1.170 0-2.706 9),1.048 9(0.560 5-2.172 5),and 0.882 0(0.512 6-1.503 1),respectively.Compared with the control group,normal group from the endemic area,and no obvious hepatopathy group,the mRNA relative expressions of Nrf2 were upregulated in the mild and moderate-severe hepatopathy group,however,the mRNA relative expressions of Keapl downregulated and SOD activity decreased(P<0.05 or P<0.01).The activities of GSH-Px and TrxR decreased in the moderate-severe hepatopathy groups,however,MDA content increased obviously(P<0.05 or P<0.01).The correlation analyses showed that the transcriptional expressions of Nrf2 were inversely correlated with enzyme activities,and positively correlated with MDA content(P<0.05 or P<0.01).The transcriptional expressions of Keapl were positively correlated with enzyme activities(P<0.05 or P<0.01).ConclusionArsenic may affect the levels of oxidative stress via regulating transcriptional expressions of Nrf2 and Keapl,and may be involved in the development of arsenism liver injury.