Kaneko Takeaki, Fujii Satoshi, Matsumoto Akio, Goto Daisuke, Ishimori Naoki, Watano Keiko, Furumoto Tomoo, Sugawara Taeko, Sobel Burton E, Kitabatake Akira
Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
Arterioscler Thromb Vasc Biol. 2002 May 1;22(5):855-60. doi: 10.1161/01.atv.0000014427.80594.8f.
Plasminogen activator inhibitor-1 (PAI-1) inhibits fibrinolysis and proteolysis. Basic fibroblast growth factor (bFGF) stimulates angiogenesis, which requires regional proteolysis. Because modulation of vasculopathy requires tight control of proteolysis, effects of bFGF on PAI-1 expression in endothelial cells (ECs) were characterized. bFGF increased PAI-1 mRNA and accumulation of PAI-1 protein in conditioned media in human umbilical vein ECs. The bFGF-mediated increase in PAI-1 mRNA was attenuated by inhibition of extracellular signal-regulated kinase kinase in human ECV304 cells. The rate of decrease in PAI-1 mRNA after actinomycin D treatment was not affected by bFGF. Transient transfection assays of the human PAI-1 promoter-luciferase construct demonstrated that bFGF-induced PAI-1 transcription was dependent on the elements within the -313 to -260 bp relative to the transcription start site. This region contains an E26 transformation specific 1 (Ets-1)-like site. Electrophoretic mobility shift assay showed that bFGF increased nuclear translocation or DNA binding of the Ets-1-like transcription factor to the PAI-1 promoter. Nucleotide substitution to disrupt the Ets-1-like site reduced bFGF-stimulated promoter activity. Fenofibric acid, an agonist ligand for the peroxisome proliferator-activated receptor-alpha, inhibited basal and bFGF-stimulated PAI-1 expression. By inducing PAI-1 expression from ECs, bFGF may control proteolysis and fibrinolysis in vessel walls.
纤溶酶原激活物抑制剂-1（PAI-1）可抑制纤维蛋白溶解和蛋白水解。碱性成纤维细胞生长因子（bFGF）可刺激血管生成，而血管生成需要局部蛋白水解。由于血管病变的调节需要对蛋白水解进行严格控制，因此对bFGF对内皮细胞（ECs）中PAI-1表达的影响进行了表征。bFGF增加了人脐静脉内皮细胞条件培养基中PAI-1 mRNA的表达及PAI-1蛋白的积累。在人ECV304细胞中，细胞外信号调节激酶激酶的抑制减弱了bFGF介导的PAI-1 mRNA的增加。放线菌素D处理后PAI-1 mRNA的下降速率不受bFGF影响。人PAI-1启动子-荧光素酶构建体的瞬时转染试验表明，bFGF诱导的PAI-1转录依赖于相对于转录起始位点-313至-260 bp内的元件。该区域包含一个E26转化特异性1（Ets-1）样位点。电泳迁移率变动分析表明，bFGF增加了Ets-1样转录因子向PAI-1启动子的核转位或DNA结合。破坏Ets-1样位点的核苷酸取代降低了bFGF刺激的启动子活性。非诺贝特酸是过氧化物酶体增殖物激活受体-α的激动剂配体，可抑制基础状态及bFGF刺激的PAI-1表达。通过诱导内皮细胞表达PAI-1，bFGF可能控制血管壁中的蛋白水解和纤维蛋白溶解。
