Paeoniflorin suppresses vascular damage and the expression of E-selectin and ICAM-1 in a mouse model of cutaneous Arthus reaction

Paeoniflorin (PF) extracted from the root of Paeonia lactiflora pall, displays anti-inflammation properties in several animal models. Adhesion molecules are important for the recruitment of leucocyte to the vessel wall and involved in the pathogenesis of various autoimmune and inflammatory diseases. Herein, we investigate the effects of PF on adhesion molecule expression in a mouse model of cutaneous Arthus reaction and cultured human dermal microvascular endothelial cells (HDMECs). We showed that PF significantly ameliorated the immune complex (IC) induced vascular damage, leucocyte infiltrates and adhesion molecules expression. Furthermore, PF markedly blocked tumor necrosis factor- (TNF-)-induced E-selectin and intercellular adhesion molecule-1 (ICAM-1) expression in HDMECs at both mRNA and protein levels. PF also suppressed TNF--induced adhesion of polymorphonuclear leucocytes (PMNs) to HDMECs. Finally, western blot data revealed that PF can inhibit the phosphorylation of p38, JNK in TNF--treated HDMECs. These data suggest that PF, as an anti-inflammatory agent, can downregulate adhesion molecules expression. PF may be a candidate medicine for the treatment of IC-induced inflammatory response.