Probucol inhibits oxidized-low density lipoprotein-induced adhesion of monocytes to endothelial cells in vitro

AIM: To investigate the mechanism by which probucol (PBC) affected adhesion of monocytes to human umbilical vein endothelial cells (HUVEC). METHODS: Effects of PBC on expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), P-selectin, a nd E-selectin in human umbilical vein endothelial cells were examined. Moreover, the inhibitory effect of PBC were compared with that of monoclonal antibodies (mAbs) to ICAM-1, VCAM-1, P-selectin, and E-select in on adhesion induced by oxidized-low density lipoprotein(Ox-LDL). RESULTS: PBC at 10 to 80 micromol/L inhibited Ox-LD L-induced adhesion index from 16.7 % to 7.0 % (P < 0.01) and Ox-LDL-induced expression of ICAM-1 (75 %) and P-selectin (72 %). mAbs to ICAM -1 or P-selectin, when used alone, could only slightly reduce the adhesion of monocyte to HUVEC. When both monoclonal antibodies were used in combination, the adhesion was markedly inhibited from 16.7 % to 11.3 % (P < 0.01), but the effect was still weaker than that of PBC (average 9.3 %). CONCLUSION: PBC exerts its inhibitory effect on the adhesion of monocyte to HUVEC by inhibiting the expression of ICAM-1 and P-selectin.