Effects of (-)-Epigallocatechin Gallate on HMGB1 and Interleukin-1β-Mediated Barrier Disruption in Human Endothelial Cells

High plasma levels of interleukin (IL)-1 beta and high mobility group box protein I (HMGB I) correlate with poor prognosis and increased mortality in patients with severe inflammation. (-)-Epigallocatechin gallate (EGCG), the main catechin in green tea, has multiple beneficial effects on reduction of inflammatory diseases; however, effects of EGCG on both IL-1 beta- and HMGB1-mediated barrier disruptive responses of human umbilical vein endothelial cells (HUVECs) have not been examined. Thus, effects of EGCG on IL-1 beta- and HMGB I -mediated barrier disruption in HUVECs were investigated. EGCG potently inhibited IL-1 beta or HMGB1-mediated permeability and down-regulated IL-1 beta 7and HMGB1-dependent adhesion and migration of THP-1 to activated HUVECs by inhibiting the activation of nuclear factor (NF)-kappa B and expression of tumor necrosis factor (TNF)-alpha. EGCG inhibited IL-1 beta- and HMGB1-mediated expression of cell adhesion molecules. Results showed EGCG has barrier protective activities and may represent a strategy to treat various inflammatory conditions mediated through the inhibition of IL-1 beta and HMGB1 signaling pathways.