Effect of vitamin E on ox-LDL-induced monocyte/endothelium adhesion

AIM:To observe the role of ox-LDL in rabbit endothelium/circulating monocyte adhesion in vitro and the effect of vitamin E.METHODS:Cultured rabbit's endothelial cells were incubated with different concentrations of ox-LDL, then incubated with rabbit's monocytes to observe cell's adhesion. With Northern blotting, endothelial VCAM-1 mRNA expression was measured. By using vitamin E incubation before ox-LDL, above steps were repeated to observe the effect of vitamin E.RESULTS:When ox-LDL concentrations were 2.5 mg/L,5 mg/L,10 mg/L,monocytes adhesive to endothelium per microscope field were 132.8±20.2,350.0±37.2,502.6±78.8,respectively They were al significantly higher than that of control group(51.2±7.7,P<0.01)Addition of vitamin Eat comcentration of 10 mol/L,20 mol/L,40 mol/L respect ively before ox-LDL incubation yield fewer adhesive monocytes as follow:422.3±32.2,296.0±21.7,205.2±36.6,respectively,but only the last two concentrations had significant effects(P<0.01)Endothelial VCAM-1 mRNA expression in ox-LDL group was higher than that in vitamin E group(0.49±0.09 vs 0,33±0.10,P<0.05).CONCLUSIONS:ox-LDL directly enhances rabbit's endothelium/monocyte adhesion by inducing expression of VCAM-1 in endothelium. Vitamin E inhibites these effects of ox-LDL.