BACKGROUND The isoflavone puerarin is the most abundant isoflavone-C-glucoside extracted from the root (radix puerariae) of the plant Pueraria lobata and possesses many biological activities. In this report, the ability of puerarin to modulate intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and endothelial leukocyte adhesion molecule 1 (E-selectin), and to induce changes in the nuclear factor kappaB (NF-kappaB) pathway in human umbilical vein endothelial cells (HUVECs) was examined. METHODS The protein and mRNA levels of tumor-necrosis-factor-alpha (TNF-alpha)-induced ICAM-1, VCAM-1 and E-selectin were determined in HUVECs. Inhibitor kappaB (I-kappaB) phosphorylation and p65 NF-kappaB expression in HUVECs were also examined. RESULTS Puerarin inhibited the expression of TNF-alpha-induced ICAM-1, VCAM-1 and E-selectin proteins and mRNAs in HUVECs. Subsequently, we determined that the inhibition of ICAM-1, VCAM-1 and E-selectin expression was due to a dose-dependent suppression of phosphorylation and degradation of I-kappaB, which resulted in a reduction of p65 NF-kappaB nuclear translocation. CONCLUSION These data suggested that the effect of puerarin-mediated inhibition of TNF-alpha-induced ICAM-1, VCAM-1 and E-selectin expression is attributed to suppressed NF-kappaB activation on the transcriptional level.