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 (P0.01). 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 (P0.05). 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.