羟基红花黄色素A对氧化低密度脂蛋白诱导的血管平滑肌细胞增殖的抑制作用

Inhibitory effect of hydroxy-safflor yellow A on proliferation of vascular smooth muscle cells stimulated by oxidized low-density lipoprotein

目的探讨羟基红花黄色素A(HSYA)抑制氧化低密度脂蛋白(ox-LDL)诱导血管平滑肌细胞(VSMC)增殖与细胞外信号调节激酶1/2(ERK1/2)和丝裂原活化蛋白激酶磷酯酶-1(MKP-1)基因转录及蛋白表达之间的关系。方法 HSYA 10μmol.L-1和ox-LDL 35 mg.L-1与VSMC共培育48 h,MTT检测细胞存活率,流式细胞术检测细胞周期,逆转录PCR(RT-PCR)观察ERK1/2和MKP-1基因表达,Western印迹法观察ERK1/2和MKP-1蛋白表达。结果与ox-LDL 35 mg.L-1模型组比较,加入HSYA 10μmol.L-1组细胞存活率明显下降,G0/G1期细胞明显增多,ERK1 mRNA表达下降了42.2%(P<0.01),MKP-1 mRNA显著增加了86.9%(P<0.01),p-ERK1/2蛋白表达降低了39.9%(P<0.01),MKP-1蛋白表达增加了80.6%(P<0.01);加入PD98059 10μmol.L-1组,细胞存活率明显降低了58.3%(P<0.01),G0/G1期细胞明显增多(P<0.01),ERK1 mRNA表达下降了45.9%(P<0.01);p-ERK1/2蛋白表达下降了45.9%(P<0.01);PD98059 10μmol.L-1+HSYA 10μmol.L-1同时加入,细胞生存率下降了61.9%(P<0.01),G0/G1期细胞明显增多(P<0.01),ERK1 mRNA表达进一步减少(P<0.01),MKP-1 mRNA增加了110%(P<0.01),p-ERK1/2蛋白表达下降了51.2%(P<0.01),MKP-1蛋白表达增加了62.4%(P<0.01)。结论 HSYA通过增强MKP-1蛋白表达、降低p-ERK1/2蛋白活性和抑制细胞周期运转的机制抑制VSMC增殖。

OBJECTIVE To investigate the relationships between the inhibition by hydroxyl-safflor yellow A（HSYA） of the ox-LDL-stimulated proliferation of rat vascular smooth muscle cells（VSMC） and the mRNA transcriptions as well as protein expressions of signaling molecules extracellular signal-regulated kinase 1/2（ERK1/2） and mitogen-activated protein kinase phospatase-1（MKP-1）.METHODS VSMC were co-incubated with HSYA 10 μmol·L-1＋ox-LDL 35 mg·L-1 for 48 h.Cell viability was assessed by the MTT assay.Cell cycle of VSMC was determined through flow cytometry（FCM）.The mRNA transcriptional level and protein expression of ERK1/2 and MKP-1 were detected by means of reverse transcription-polymerase chain reaction（RT-PCR） and Western blot analysis,respectively.RESULTS Compared with ox-LDL 35 mg·L-1 model group,the survival rate significantly decreased,ratio of cells in G0/G1 phase increased,ERK1 mRNA and p-ERK1/2 expression decreased by 42.2% and 39.9%（P0.01）,respectively,and the mRNA transcription and protein expression of MKP-1 increased by 86.9% and 80.6%（P0.01）,respectively in HSYA 10 μmol·L-1 group.PD98059 10 μmol·L-1 significantly decreased survival rate by 58.3%（P0.01）,increased the ratio of cells in G0/G1 phase by 75.0%（P0.01）,decreased ERK1 mRNA expression by 45.9 %（P0.01） and p-ERK1/2 expression by 45.9%（P0.01）.In HSYA 10 μmol·L-1＋PD98059 10 μmol·L-1 group,the survival rate decreased by 61.9%（P0.01）,the ratio of cells in G0/G1 phase significantly increased（P0.01）,ERK1 mRNA and ERK1/2 protein expressions reduced by 79.1%（P0.01） and 51.2%（P0.01）,respectively,as well as expressions of MKP-1mRNA and protein increased by 110% and 62.4%（P0.01）,respectively.CONCLUSION HSYA inhibits ox-LDL-stimulated VSMC proliferation through increasing in MKP-1 expression,decreasing in ERK1/2 and suppressing the cell cycle progression.