Figure 1

Effect of (−)-epigallocatechin gallate on lipopolysaccharide-induced inflammatory cytokine expression at both mRNA and protein levels. Human cerebral microvascular endothelial cells/D3 (hCMEC/D3) were treated with or without lipopolysaccharide (LPS) at 100 ng/mL for the indicated time periods (A,D,G,J) or at indicated concentrations for 6 h (B,H) or 24 h (E,K). (C,F,I and L) hCMEC/D3 cells were pretreated with (−)-epigallocatechin gallate (EGCG) at the indicated concentrations for 1 h prior to LPS treatment (100 ng/mL) for an additional 6 h (C,I) or 24 h (F,L). The mRNA expression was determined by quantitative real time PCR, and protein levels in the culture medium were measured by conventional ELISA. Data are expressed as mean ± SD of three different experiments (*P < 0.05, **P < 0.01, compared with no treatment control or LPS treatment only).