细胞外信号调节激酶信号通路对乙醛刺激的大鼠肝星状细胞周期的影响

目的 观察特异性丝裂原细胞外信号反应激酶1(MEK 1)阻断剂(PD98059)对乙醛刺激的大鼠肝星状细胞(HSC)增殖及细胞周期的影响,并探讨其作用机制。 方法 用不同浓度的PD98059对乙醛刺激的HSC进行处理;以四甲基偶氮唑蓝法检测细胞增殖,流式细胞仪检测细胞周期,逆转录聚合酶链反应方法检测HSC内细胞周期蛋白-D1(Cyclin D1)mRNA和细胞周期蛋白依赖性激酶(CDK4)mRNA的表达。 结果 20、50、100μmol/L的PD98059均能显著且剂量依赖性地抑制乙醛刺激的HSC增殖,3组A值分别为0.109±0.020、0.081±0.010、0.056±0.020,与乙醛组A值0.146±0.030相比较,F=31.385,P<0.05;20、50、100 μmol/L的PD98059可显著抑制乙醛刺激的HSC由G1期进入S期,G0/G1期细胞百分比逐渐升高,3组G0/G1期细胞百分比分别为(61.9±6.3)％、(64.1±3.3)％、(70.9±4.8)％,与乙醛组(55.2±4.4)％相比较,F=16.402,P<0.05;50、100μmol/L的PD98059能显著抑制乙醛刺激的HSC内Cylin D1 mRNA表达,2组平均光强度比值分别为0.56±0.04,0.46±0.03,与乙醛组0.65±0.07相比较,F=68.758,P<0.05;50、100μmol/L的PD98059能显著抑制乙醛刺激的HSC内CDK4 mRNA表达,2组平均光强度比值分别为0.39±0.07,0.33±0.05,与乙醛组0.50±0.06相比较,F=29.406,P<0.05。 结

Effects of Erk signal transduction on the cell cycle of rat hepatic stellate cells stimulated by acetaldehyde

OBJECTIVE: To investigate the effect of PD98059 on the proliferation and cell cycle of rat hepatic stellate cells (HSCs) stimulated by acetaldehyde and explore its mechanism. METHODS: Rat HSCs stimulated by acetaldehyde were incubated with different concentrations of PD98059. Cell proliferation was assessed by MTT colorimetric assay. Cell cycle was analysed by flow cytometry. The mRNA of cyclin D1 and CDK4 were examined by RT-PCR. RESULTS: 20, 50, 100 micromol/L PD98059 could significantly inhibit the proliferation of HSCs stimulated by acetaldehyde in a does-dependent manner (0.109+/-0.020, 0.081+/-0.010 and 0.056+/-0.020 vs 0.146+/-0.030, F=31.385, P<0.05) and provoke G0/G1 phase arrest of HSCs stimulated by acetaldehyde in a does-dependent manner (61.9%+/-6.3%, 64.1%+/-3.3% and 70.9%+/-4.8% vs 55.2%+/-4.4%, F=16.402, P<0.05). 50, 100 micromol/L PD98059 could markedly inhibit cyclin D1 mRNA expression of HSC stimulated by acetaldehyde (0.56+/-0.04 and 0.46+/-0.03 vs 0.65+/-0.07, F=68.758, P<0.05) and CDK4 mRNA expression (0.39+/-0.07 and 0.33+/-0.05 vs 0.50+/-0.06, F=29.406, P<0.05). CONCLUSION: The Erk signal transduction pathway plays an important role in regulating the proliferation and cell cycle of rat hepatic stellate cells stimulated by acetaldehyde, which may be partly related to its regulative effect on the expression of cyclin D1 gene and CDK4 gene