LOX-1对氧化低密度脂蛋白所诱导的PAI-1基因表达的影响

目的探讨血凝素样氧化型低密度脂蛋白受体(LOX)-1对氧化低密度脂蛋白(ox-LDL)所诱导1型纤溶酶原激活物抑制剂-1(PAI-1)表达的影响。方法不同浓度ox-LDL培养人脐静脉内皮细胞(HUVECs),采用倒置显微镜观察内皮细胞形态变化,通过反转录-聚合酶链反应(RT-PCR)测定LOX-1、PAI-1mRNA表达,Westernblot、酶联免疫吸附试验(ELISA)分别测定LOX-1、PAI-1蛋白的表达。结果不同浓度ox-LDL组,LOX-1和PAI-1mRNA和蛋白的表达明显增加,且呈浓度依赖性(P<0.01);用250μg/mLPoly(Ⅰ)与HUVECs预先作用2h后,再加入50μg/ml的ox-LDL培养24h,与未加Poly(Ⅰ)相比,LOX-1和PAI-1mRNA和蛋白的表达明显减少(P<0.05)。结论ox-LDL可以调节培养的脐静脉内皮细胞LOX-1和PAI-1表达;LOX-1作为ox-LDL特异性受体,介导了ox-LDL诱导脐静脉内皮细胞表达LOX-1。同时该实验提示了ox-LDL诱导脐静脉内皮细胞表达PAI-1是通过LOX-1介导的。

Effects of lectin-like oxidized LDL receptor-1 on the expression of plasminogen activator inhibitor-1 induced by ox-LDL in human umbilical vein endothelial cells

Objective To investigate the effects of lectin-like oxidized LDL receptor-1 （LOX-1） on expression of PAI-1 induced by ox-LDL in human umbilical vein endothelial cells （HUVECs）. Methods HUVECs were incubated with different levels of ox-LDL （10, 25, 50 and 100 μg/ml）, or pretreated with 250 μg/ml poly （Ⅰ） for 2 h before incubated with 50 μg/ml ox-LDL, for 24 h. Expressions of LOX-1 and PAI-1 mRNA were determined by RT-PCR, and LOX-1 and PAI-1 proteins examined with Western blott and ELISA, respectively. Results Incubation of HUVECs with ox-LDL （10, 25, 50, 100 μg/ml） enhanced the expressions of LOX-1 and PAI-1 in a concentration-dependent manner （P〈0.01）. The expressions of LOX-1 and PAI-1 induced by ox-LDL were reduced in HUVECs pretreated with 250 μg/ml poly （Ⅰ） for 2 h before incubated with 50 μg/ml ox-LDL for 24 h, compared with those not pretreated （P〈 0.05）. Conclusion ox-LDL was shown to regulate the expressions of LOX-1 and PAI-1 in HUVECs. LOX-1 as the ox-LDL specific receptor was also implied to mediate the expression of PAI-1 induced by ox-LDL in HUVECs .