HIF-1α、ROCK-2、FoxM1在醋酸铅诱导PC12细胞损伤中的表达变化

摘要

Aim To investigate the expression and im-plication of HIF-1α, ROCK-2 , FoxM1 in PC12 cell in-jury induced by lead acetate. Methods PC12 cells were treated with lead acetate at the doses of 100 , 200 and 400 μmol·L-1 . The cell viability was determined by MTT reduction assay and LDH assay, the intracellu-lar production of oxygen species was measured by as-sessing SOD and MDA levels, cell apoptosis was deter-mined by Hoechst 33342 staining, the expressions of HIF-1α, ROCK-2 , FoxM1 , Bcl-2 and Bax were deter-mined by immunoblotting analysis. Results Lead ac-etate induced cell injury in PC12 cells in a dose-de-pendent manner, and it potentiated oxygen radical pro-duction and cell apoptosis. In addition, lead acetate enhanced HIF-1α and ROCK-2 expressions, increased Bax/Bcl-2 ratio and decreased FoxM1 expression. Conclusion Lead acetate can induce PC12 cell apop-tosis, which may be related with the expressions of HIF-1α, ROCK-2 and FoxM1 . Cellular oxidative stress may contribute to the injury as well.%目的探讨低氧诱导因子-1α( hypoxia inducible factor-1α, HIF-1α)、Rho关联卷曲螺旋蛋白激酶-2( Rho associated coiled coil forming protein kinase-2, ROCK-2)、叉头蛋白 M1(forkhead box protein M1, FoxM1)在醋酸铅[Pb(Ac)2]诱导大鼠肾上腺嗜铬细胞瘤PC12细胞损伤中的表达和意义。方法将PC12细胞暴露于不同浓度的Pb(Ac)2(100、200、400μmol·L-1)24 h以诱导细胞发生损伤。采用噻唑蓝比色法检测细胞的存活率,倒置显微镜观察细胞形态的变化,乳酸脱氢酶漏出率检测法测定细胞损伤程度,采用试剂盒检测丙二醛( malondialdehvde, MDA)和超氧化物歧化酶( superoxide dismutase, SOD)水平, Hoechst 33342单荧光染色法观察细胞凋亡,免疫印迹法检测细胞HIF-1α、ROCK-2、FoxM1、淋巴瘤/白血病-2(B cell lymphoma/leukemia, Bcl-2)和Bcl-2相关蛋白(Bcl-2 associated X protein, Bax)的表达。结果 MTT实验显示Pb( Ac)2对PC12细胞具有明显抑制作用并呈剂量依赖性,与对照组相比, Pb ( Ac )2可增加细胞内 LDH 漏出率,升高MDA含量,降低SOD含量,诱导细胞发生凋亡。此外,Pb( Ac)2上调细胞HIF-1α、ROCK-2的表达,下调FoxM1的表达,提高Bax/Bcl-2的表达比例。结论 Pb(Ac)2诱导PC12细胞发生凋亡可能与HIF-1α、ROCK-2、FoxM1的表达以及自由基损伤有关。