Abstract
We studied the role of poly-ADP-ribose polymerase (PARP) in the mobilization of ICAM-1, VCAM-1, and E-selectin by TNF-alpha and IL-1beta in cultured human endothelial cells. Enzyme linked immunosorbent analysis (ELISA) was used to assess if ICAM-1, VCAM-1, and E-selectin were expressed at the cell surface, and if PARP inhibition (using the selective PARP inhibitor GPI 6150) blocked the induced expression. Endothelial cell adhesion molecule expression was evaluated at 4 and at 24 h after cytokine stimulation. At 4 h ICAM-1 and E-selectin, but not VACM-1, were stimulated by both IL-1beta and TNF-alpha. Blocking PARP via GPI 6150 only affected TNF-alpha induced E-selectin expression at 4 hours. ICAM-1, VCAM-1, and E-selectin expression were all stimulated by both IL-1beta and TNF-alpha in the 24 h assays. PARP inhibition with GPI 6150 blocked the IL-1beta mediated stimulation of both ICAM-1 and E-selectin expression, and blocked TNF-alpha stimulation of ICAM-1 expression at 24 h. These experiments suggest that specific PARP inhibition may provide a novel method of controlling leukocyte dependent inflammation through the reduction of ICAM-1 and E-selectin expression in endothelial cells in response to cytokines.