OBJECTIVETo investigate the effects of valsartan on cyclooxygenase-2 (COX-2) in cultured human umbilical vein endothelial cells (HUVECs) stimulated by ox-LDL.

METHODSHUVECs were cultured in endothelial basal medium and divided into four groups (n = 5 each): group I, control group without any treatment; group II: HUVECs stimulated with ox-LDL (100 mg/L) in endothelial basal medium for 24 hours; group III: HUVECs treated with ox-LDL (100 mg/L) and valsartan (10 µmol/L) in endothelial basal medium for 24 hours; group IV: HUVECs treated with ox-LDL (100 mg/L) and valsartan (30 µmol/L) in endothelial basal medium for 24 hours. Expression of COX-1 and COX-2 mRNA were determined by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSExpression of and COX-2 mRNA was significantly higher in ox-LDL-treated HUVECs than in control group (1.478 ± 0.104 vs. 0.366 ± 0.104, P < 0.05), while expression of COX-1 mRNA was similar between the 2 groups (P > 0.05). Valsartan dose-dependently decreased the COX-2 mRNA expression (group III vs. group II: 1.074 ± 0.112 vs. 1.478 ± 0.104, P < 0.05; group IV vs. group II: 0.664 ± 0.104 vs. 1.478 ± 0.104, P < 0.05). Expression of COX-1 mRNA in ox-LDL-treated HUVECs was not affected by valsartan.

CONCLUSIONSCOX-2 mRNA expression in ox-LDL-treated HUVECs could be reduced by valsartan suggesting valsartan might attenuate atherosclerosis by reducing ox-LDL-induced inflammatory responses.