Increased trans-endothelial cells permeability induced by oxidized lipoprotein(a) relates to reactive oxygen species generation and desmogleins expression

Aim: we aim at measurement enhanced effect of oxidized lipoprotien(a) [oxLp(a)] on permeability of monolayer endothelial cells and relationship with reactive oxygen spe-cies(ROS) generation and desmogleins(DSGs) expression. Methods and Results : Trans-endothelial permeability was assayed by transwell and reactive oxygen species(ROS) was determined by DCFH-DA staining. RT-PCR was carried out to determine DSG1 and DSC2 expression in mRNA, respectively. Trans-endothelial permeability was enhanced by oxLP(a) dose and time dependently. The most marked effect appeared at a concentration of 100 mg/L, Trans-endothelial permeability reached the maximum value after 2 h of FITC-dextran addition, and then gradually decreased after 4 h. oxLp(a) induces the generation of cellular reactive oxygen species (ROS), and this effect could be inhibited by superoxide dismutase(SOD). Incubation of HUVECs with oxLp(a) resulted in a dose and time-dependent down-regulation of DSG1 and DSC2 expression at transcriptional level. Conclusion : permeability of monolayer endothelial cells was enhanced by oxLp(a) and it is related to up-regulating ROS formation and down-regulating desmogleins expression.