Reactive oxygen species mediate oxidized low-density lipoprotein-induced endothelin-1 gene expression via extracellular signal-regulated kinase in vascular endothelial cells

• DOI: 10.1097/hjh.0b013e3282f56bb7
• Publication Date: 2008-04-01T07:09:53Z
• Authors: Haishan Xu; Jinhong Duan; Wen Wang; Shunling Dai; Yunqing Wu; Renyu Sun; Jun Ren
• Keywords: Umbilical Veins; Endothelin-1; Endothelial Cells; Lipoproteins, LDL; 03 medical and health sciences; 0302 clinical medicine; Gene Expression Regulation; Humans; Phosphorylation; Extracellular Signal-Regulated MAP Kinases; Reactive Oxygen Species; Cells, Cultured; Signal Transduction

Oxidized low-density lipoprotein (oxLDL) promotes expression and secretion of endothelin-1 (ET-1), however, the precise mechanism involved is unclear. This study was designed to identify regulatory oxLDL-induced ET-1 in endothelial cells.ET-1 mRNA expression, promoter activity were evaluated by reverse transcriptase-PCR (RT-PCR), enzyme immunometric luciferase assays, respectively.oxLDL (35 microg/ml) significantly enhanced reactive oxygen species (ROS), human umbilical vein cells (HUVECs), all which nullified antioxidant N-acetyl cysteine (NAC). oxLDL stimulated extracellular signal-regulated kinase (ERK) phosphorylation HUVECs, blocked NAC mitogen-activated protein/extracellular (MEK) inhibitor PD98059. PD98059 stopped oxLDL-elicited increase ET-1. Fusion plasmids with decreasing length 5'-flanking sequence from -566 bpLuc -250 displayed increased after 24 h treatment. Interestingly, fusion plasmid -233 -185 reduced control oxLDL-treated HUVECs. In addition, transfection reporter construct -250Luc, contains a 2 bp mutation at activator protein-1 site, abolished both basal oxLDL-stimulated activities.Collectively, our data favor notion that stimulates ERK via ROS accumulation, turn vascular transcriptional factor as well secretion.