Differential mechanisms of plasminogen activator inhibitor-1 gene activation by transforming growth factor-β and tumor necrosis factor-α in endothelial cells
Differential mechanisms of plasminogen activator inhibitor-1 gene activation by transforming growth factor-β and tumor necrosis factor-α in endothelial cells
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DOI：
10.1055/s-0037-1616763
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发表时间：
2001-12-01
影响因子：
6.7
通讯作者：
Tseng-Crank, J
中科院分区：
文献类型：
--
作者：
Chen, YQ;Sloan-Lancaster, J;Tseng-Crank, J
纤溶酶原激活物抑制剂-1（派-1）是一种丝氨酸蛋白酶抑制剂（SERPIN），对组织型和尿激酶样纤溶酶原激活物具有特异性。高血浆派-1活性是血栓性疾病的危险因素。由于派-1的半衰期短，派-1基因表达的调节和活性派-1 I分泌到血流中对于止血平衡是重要的。我们用派-1 5'启动子-荧光素酶报告基因分析法研究了派-1基因在牛主动脉内皮细胞（BAECs）和人细胞系中表达的转录调控。相反，奎宁诱导的派-1 mRNA和蛋白水平的上调，我们发现，只有转化生长因子-β（TGF-β）是有效的诱导派-1启动子激活。组织坏死因子-α（TNF-α）诱导一个小的荧光素酶活性与2.5 kb派-1启动子，但不与派-800/4G/5G和p3 TP-lux启动子。接下来，我们研究了对TNF-α缺乏反应是否是由于信号传导途径缺陷，BAEC对TNF-α的反应具有强大的NF κ B启动子激活。TGF-β激活p38 MAP激酶，而TNF-α激活SAPK/JNK和p38 MAP激酶。ERK 1/2 MAP激酶在BAEC中被组成性激活。因此BAEC对TNF-α刺激有反应，激活MAP激酶和NF κ B转录因子。我们进一步测量了TGF-β和TNF-α影响下的信使RNA稳定性，没有发现差异。由TNF-α激活的派-1基因显然还没有被确定为应答元件和/或信号通路的位置，而TGF-β是通过其5'近端启动子激活派-1转录的最重要的细胞因子。
Plasminogen activator inhibitor-1 (PAI-1) is a serine protease inhibitor (SERPIN) specific for tissue-type and urokinase-like plasminogen activators. High plasma PAI-1 activity is a risk factor for thrombotic diseases. Due to the short half-life of PAI-1, regulation of PAI-1 gene expression and secretion of active PAI-1 I into the blood stream is important for hemostatic balance. We have investigated transcriptional control of PAI-1 gene expression in bovine aortic endothelial cells (BAECs) and human cell lines using PAI-1 5' promoter-luciferase reporter assays. Contrary to the cytokine-induced up-regulation of PAI-1 mRNA and protein levels, we found that only transforming growth factor-beta (TGF-beta) was efficient in inducing PAI-1 promoter activation. Tissue necrosis factor-alpha (TNF-alpha) induced a small luciferase activity with the 2.5 kb PAI-1 promoter, but not with the PAI-800/4G/5G and p3TP-lux promoters. Next we investigated whether a lack of response to TNF-alpha was due to deficient signaling pathways, BAECs responded to TNF-alpha with robust NF kappaB promoter activation. TGF-P activated the p38 MAP kinase, while TNF-alpha activated both the SAPK/JNK and p38 MAP kinases. The ERK1/2 MAP kinases were constitutively activated in BAECs. BAEC therefore responded to TNF-a stimulation with activation of the MAP kinases and the NF kappaB transcriptional factors. We further measured the messenger RNA stability under the influence by TGF-beta and TNF-alpha and found no difference. PAI-1 gene activation by TNF-alpha apparently is yet to be defined for the location of the response element and/or the signaling pathway, while TGF-beta is the most important cytokine for PAI-1 transcriptional activation through its 5' proximal promoter.