Rebamipide inhibits neutrophil adhesion to hypoxia/reoxygenation-stimulated endothelial cells via nuclear factor-kappa B-dependent pathway

This study was designed to determine whether rebamipide can inhibit neutrop hil adhesion to human umbilical vein endothelial cells (HUVECs) stimulated with 1 h of hypoxia followed by 4 h of reoxygenation (H/R). Furthermore, to define the action mechanisms, we determined the effect of rebamipide on th e surface expression of endothelial cell adhesion molecules E-selectin, P-s electin, and intercellular adhesion molecule-1 (ICAM-1) on H/R-stimulated H UVECs. Under resting conditions, both E-selectin and P-selectin were not ex pressed on the surface of HUVECs in contrast to ICAM-1, which was constitut ively expressed. After stimulation with H/R, HUVECs showed an enhanced neut rophil adhesivity in association with an increased surface expression of E- selectin and P-selectin with a marginal increase in ICAM-1 expression. In p arallel, the increased nuclear translocation of nuclear factor-kappa B in H /R-stimulated HUVECs was monitored by electrophoretic mobility shift assay (adjusted volume units, 11.9 +/- 2.5 x 10(4) counts x mm(2) in unstimulated cells versus 24.2 +/- 3.0 x 10(4) counts x mm(2) in H/R-stimulated cells). Rebamipide suppressed the surface expression of E-selectin and P-selectin with a subsequent inhibition of neutrophil adhesion to H/R-stimulated HUVEC s. In line with these results, rebamipide (100, 300, and 1000 mu M) inhibit ed H/R-induced nuclear translocation of nuclear factor-kappa B in a concent ration-dependent manner. Taken together, this study demonstrates that rebam ipide inhibits neutrophil adhesion to HUVECs by a mechanism involving inhib ition of transcription-dependent surface expression of E-selectin and P-sel ectin in H/R-stimulated endothelial cells.