Green tea polyphenol epigallocatechin-3-gallate inhibits TNF-α-induced production of monocyte chemoattractant protein-1 in human umbilical vein endothelial cells.

AIMS: Epigallocatechin-3-gallate (EGCG), a major catechin found in green tea, displays a variety of pharmacological properties and recently received attention as a prospective dietary intervention in cardiovascular diseases (CVD). This study was conducted to test the hypothesis that EGCG was able to inhibit tumor necrosis factor-α (TNF-α)-induced production of monocyte chemoattractant protein-1 (MCP-1) in human umbilical vein endothelial cells (HUVECs) and investigated the underlying molecular mechanisms. METHODS: The inhibitory effect of EGCG on TNF-α-induced expression of MCP-1 was measured using ELISA and RT-qPCR. The effect of EGCG on TNF-α-induced nuclear factor-kappa B (NF-κB) activation was investigated by western blot and luciferase assays. Monocyte adhesion assay was detected by microscope. RESULTS: EGCG significantly suppressed the TNF-α-induced protein and mRNA expression of MCP-1. Investigation of the mechanism suggested that EGCG suppressed the TNF-α-mediated NF-κB activation. In addition, the 67-kD laminin receptor (67LR) was involved in EGCG-mediated suppression of MCP-1 generation. Furthermore, EGCG potently inhibited monocyte adhesion to activated HUVECs. CONCLUSION: EGCG suppresses TNF-α-induced MCP-1 expression in HUVECs. This effect was mediated by 67LR and was via the inhibition of NF-κB activation. Our results demonstrated that EGCG might be a possible medicine for CVD prevention and treatment.