Epigallocatechin-3-gallate attenuates lipopolysaccharide-induced inflammation in human retinal endothelial cells.

ABSTRACT

AIM: To investigate the mechanism underlying the anti-inflammatory effects of epigallocatechin-3-gallate (EGCG) in lipopolysaccharide (LPS)-stimulated human retinal endothelial cells (HRECs). METHODS: HRECs pre-treated with EGCG (0-100 µmol/L) were stimulated with LPS (250 ng/mL). Levels of tumor necrosis factor alpha (TNF-α), vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1 (MCP-1) and nitric oxide (NO) in the supernatants were determined by enzyme-linked immunosorbent assay (ELISA) and Griess assay. The protein expression of phosphorylated extracellular signal-regulated kinase (ERK) 1/2 and p38 mitogen-activated protein kinases (p38) were determined by Western blot analysis. RESULTS: EGCG pre-treatment significantly inhibited the secretion of TNF-α, VEGF, MCP-1 and NO in LPS-stimulated HRECs. Moreover, EGCG effectively attenuated LPS-induced activation and phosphorylation of ERK1/2 and p38 in HRECs in a dose-dependent manner. CONCLUSION: EGCG exhibited inhibitory effects on LPS-induced pro-inflammatory cytokines production by modulating ERK1/2 and p38 pathways in HRECs, suggesting EGCG as a potential candidate for anti-inflammatory intervention.