摘要
目的 探讨敲低过氧化物还原酶-6(PRDX6)在利福平(RFP)诱导人肝癌细胞(HepG2)损伤及胆汁酸转运体适应性表达中的作用.方法 将处于对数生长期的细胞均匀接种于 6 孔板中,使用特异PRDX6-siRNA、control-siRNA分别转染HepG2 细胞构建敲低组及对照组.给予细胞 100 μmol/L RFP诱导24h后,Western blot和qRT-PCR检测各组细胞PRDX6、多药耐药蛋白 1(MDR1)、多药耐药相关蛋白2、3、4(MRP2、MRP3、MRP4)、Na+/牛磺胆酸协同转运蛋白(NTCP)的蛋白及基因表达水平;Annexin V-FITC/PI 双染法检测各组细胞凋亡率;CCK-8 法检测各组细胞增殖变化;试剂盒检测各组细胞培养上清液中细胞损伤标志物丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、总胆红素(TBIL)、直接胆红素(DBIL)、总胆汁酸(TBA)相对含量变化.结果 RFP 可诱导 HepG2 细胞 MRP2、MRP3、MRP4、MDR1、NTCP及PRDX6 的蛋白和基因表达水平升高(P<0.05),而敲低PRDX6 后,MRP2、MRP3、MRP4、MDR1、NTCP的蛋白和基因表达水平均有不同程度的降低(P<0.05).此外,PRDX6 敲低后HepG2 细胞凋亡率升高(P<0.05),细胞增殖能力下降(P<0.05),细胞培养上清液中细胞损伤标志物(ALT、AST、TBIL、DBIL、TBA)水平升高(P<0.05).结论 RFP可增加HepG2 细胞胆汁酸转运体及PRDX6 的蛋白和基因表达量,敲低PRDX6 并用RFP诱导后胆汁酸转运体的蛋白及基因表达量降低,同时细胞损伤加重,表明PRDX6 在RFP诱导的HepG2 细胞适应性反应中发挥保护作用.
Abstract
Objective To investigate the role of knockdown of peroxiredoxin-6(PRDX6)in injury and adaptive expression of bile acid transporter in human hepatoellular carcinomas(HepG2)cells induced by rifampicin(RFP).Methods Cells in logarithmic growth phase were uniformly inoculated in six-well plates,and HepG2 cells were transiently transfected with specific PRDX6-siRNA and control-siRNA to construct the knockdown group and control group.After 24 h of induction with 100 μmol/L RFP,Western blot and qRT-PCR were performed to detect the protein and gene expression levels of PRDX6,multidrug resistance protein 1(MDR1),multidrug resist-ance-associated proteins 2,3 and 4(MRP2,MRP3 and MRP4),and Na+/taurine taurocholate cotransporter pro-tein(NTCP).Annexin V-FITC/PI double staining assay was used to detect the apoptosis rate of cells in each group;CCK-8 assay was used to detect the changes of cell proliferation in each group;The relative contents of ala-nine aminotransferase(ALT),aspartate aminotransferase(AST),total bilirubin(TBIL),indirect bilirubin(IBIL)and total bile acid(TBA)in the supernatant of cell culture medium of each group were detected by kits.Results RFP increased the protein and gene expression levels of MRP2,MRP3,MRP4,MDR1,NTCP and PRDX6 in HepG2 cells(P<0.05),while the protein and gene expression levels of MRP2,MRP3,MRP4,MDR1 and NTCP decreased to different degrees after PRDX6 knockdown(P<0.05).In addition,PRDX6 knockdown re-sulted in increased apoptosis rate of HepG2 cells(P<0.05),decreased cell proliferation ability(P<0.05),and increased levels of cell injury markers(ALT,AST,TBIL,DBIL,TBA)in cell culture supernatants(P<0.05).Conclusion RFP increased the protein and gene expression of bile acid transporter and PRDX6 to increase in HepG2 cells.However,following knockdown of PRDX6 and treatment with RFP,the protein and gene expression levels of the bile acid transporter decreased and cell injury was aggravated,suggesting that PRDX6 played a protec-tive role in RFP-induced adaptive response in HepG2 cells.