过氧化体增殖物激活型受体对血管内皮细胞PAI-1转录的调节

The influence of peroxisome proliferator-activated receptors on transcription of plasminogen activator inhibitor-1 in endothelial cells

目的 :探讨血管内皮细胞中过氧化体增殖物激活型受体 (PPARs)的表达及其对纤溶酶原激活物抑制剂 - 1(PAI- 1)转录的调节作用。方法 :培养人脐静脉内皮细胞 (HUVECs)并提取总RNA ,通过逆转录聚合酶链式反应 (RT -PCR)扩增PPARα、δ和γ ;以PAI - 1启动子控制表达氯霉素转移乙酰酶 (CAT)报告基因的重组质粒PAI-pCAT转染人血管内皮细胞株ECV30 4、并同时分别共转染 2 5 0、5 0 0、10 0 0ng的PPARα或PPARγ表达载体 ,酶联免疫吸附方法 (ELISA)测定CAT表达量 -启动子片段转录活性。结果 :HUVECs中可检测到PPARα、δ和γ的mRNA水平表达 ,并且表达量PPARγ明显小于PPARα(P <0 0 1)和PPARδ(P <0 0 1) ;增加PPARα表达可剂量依赖地提高ECV30 4细胞PAI- 1转录 ,而增加PPARγ表达对ECV30 4细胞PAI - 1的转录无影响。结论 :血管内皮细胞存在 3种PPARs的表达 ,其中PPARα涉及对PAI-

AIM: To investigate the expression of peroxisome proliferator-activated receptors (PPARs) in human endothelial cells, and their effects on plasminogen activator inhibitor-1 transcription. METHODS: The expression of three types of PPARs in mRNA level were detected in human umbilical vein endothelial cells(HUVECs) by using RT-PCR. Cultured endothelial cells line-ECV304 were transfected with PAI-1 promoter controlling CAT reporter gene and co-transfected with varying doses (250, 500, 1 000 ng) of expression vectors PPARα or PPARγ.The transcripton activity of PAI-1 promoter were detected with ELISA. RESULTS: There were all three types of PPARs mRNA expression in HUVECs, while the expression of PPARγ was less than that of PPARα( P< 0.01)and PPARδ( P< 0.01). Enhancing expression level of PPARα induced the transcription activity of PAI-1 promoter in a dose-dependent manner, and there was no effect in enhancing expression of PPARγ. CONCLUSION: There were all three types of PPARs mRNA expression in endothelium; PPARα acted in the induction of PAI-1 transcription in endothelial cells.