Effects of tanshinone II-A sulfonate on adhesion molecule expression of endothelial cells and platelets in vitro

AIM: To study the action of tanshinone II-A sulfonate (Tan) on adhesion molecule expression by cultured endothelial cells and platelets. METHODS: Tumor necrosis factor alpha (TNF-alpha)-induced ICAM-1 expression on the cell surface and endothelial adhesivity toward HL-60 cells were studied using human umbilical vein endothelial cells (HUVEC). Thrombin-induced expression of platelet P-selectin was studied using human blood platelets. Adhesion molecule expression on the cell surface was measured by now cytometry. The number of HL-60 cells adhering to the HUVEC monolayer was determined by liquid scintillation spectroscopy. RESULTS: Pretreatment of HUVEC with TNF-alpha significantly enhanced ICAM-1 expression and increased HL-60 cells adhesion to HUVEC from 4.6 % +/- 0.7 % to 30 % +/- 6 %. Tan (25-200 mu mol.L-1) inhibited the effects of TNF-alpha in a concentration-dependent manner. Tan also inhibited the increase of P-selectin expression of thrombin-activated platelets in a concentration-dependent manner. CONCLUSION: Tan inhibited expression of adhesion molecules (ICAM-1, P-selectin) in HUVEC and in human blood platelets.