Interleukin-6 and mevastatin regulate plasminogen activator inhibitor-1 through CCAAT/enhancer-binding protein-δ
Interleukin-6 and mevastatin regulate plasminogen activator inhibitor-1 through CCAAT/enhancer-binding protein-δ
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DOI：
10.1161/01.atv.0000159701.24372.49
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发表时间：
2005-05-01
影响因子：
8.7
通讯作者：
Kitabatake, A
中科院分区：
文献类型：
--
作者：
Dong, J;Fujii, S;Kitabatake, A
目的：我们试图确定促炎细胞因子、白细胞介素-6 （IL-6）和他汀类药物作为纤溶酶原激活物抑制剂-1 （PAI-1）合成的调节因子的病因机制，PAI-1是一种生理性纤维蛋白溶解抑制剂和急性期反应物。方法和结果-对HepG2人肝癌细胞进行瞬时转染和荧光素酶检测表明，IL-6增加了PAI-1启动子活性，而美伐他汀降低了IL-6诱导的反应。启动子的系统缺失实验表明，该区域（- 239至- 210 bp）含有假定的CCAAT/增强子结合蛋白（C/EBP）结合位点是必要的。该位点的点突变消除了IL-6诱导的反应。电泳迁移迁移和染色质免疫沉淀实验表明，C/EBP α、C/EBP β和C/EBP δ参与了完整细胞中蛋白- DNA复合物的形成。脱氧核糖核酸酶（DNase） I足迹分析显示，5'侧区（- 232 ~ - 210 bp）是急性期反应蛋白结合位点。IL-6增加了C/EBP δ结合活性，而美伐他汀降低了其结合活性。美伐他汀可减弱IL-6介导的核提取物中C/EBP δ蛋白的升高。IL-6也增加小鼠原代肝细胞PAI-1和C/EBP δ mRNA的表达。结论：IL-6通过含有C/EBP δ结合位点的启动子的- 232 ~ - 210 bp区域介导肝脏PAI-1的表达。他汀类药物的血管保护作用可能部分通过调节CEBP δ和随后的PAI-1表达来介导。
Objective - We sought to determine the etiologic mechanism of proinflammatory cytokine, interleukin-6 (IL-6), and statin as regulators of synthesis of plasminogen activator inhibitor-1 (PAI-1), the physiological fibrinolysis inhibitor and an acute-phase reactant.Methods and Results - Transient transfection and luciferase assay in HepG2 human hepatoma-derived cells demonstrated that IL-6 increased PAI-1 promoter activity and mevastatin decreased IL-6 - inducible response. Systematic deletion assay of the promoter demonstrated that the region ( - 239 to - 210 bp) containing a putative CCAAT/enhancer-binding protein (C/EBP) binding site was necessary. Point mutation in this site abolished the IL-6 - inducible response. Electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrated that C/EBP alpha, C/EBP beta, and C/EBP delta were involved in protein - DNA complex formation in intact cells. Deoxyribonuclease ( DNase) I footprinting analysis revealed that 5' flanking region ( - 232 to - 210 bp) is acute-phase response protein-binding site. C/EBP delta binding activity was increased by IL-6 and attenuated by mevastatin. Mevastatin attenuated IL-6 - mediated increase of C/EBP delta protein in the nuclear extracts. IL-6 also increased PAI-1 and C/EBP delta mRNA in mouse primary hepatocytes.Conclusions - IL-6 increases hepatic PAI-1 expression mediated by the - 232- to - 210-bp region of the promoter containing a C/EBP delta binding site. Vascular protection by statins may be partly mediated through regulation of CEBP delta and consequent modulation of PAI-1 expression.