Figure 5

Effect of (−)-epigallocatechin gallate on the expression of Claudin-5/Occludin of human cerebral microvascular endothelial cells/D3. Human cerebral microvascular endothelial cells/D3 (hCMEC/D3) were pretreated with (−)-epigallocatechin gallate (EGCG) at the indicated doses for 1 h prior to lipopolysaccharide (LPS) treatment (100 ng/mL) for 24 h. RNA extracted was subjected to real time PCR for Claudin-5 and Occludin expression (A,B). Data are expressed as mean ± SD of three independent experiments. (C) hCMEC/D3 cells were pretreated with 5 μM EGCG for 1 h and then with 100 ng/ml LPS for 24 h. Cells were fixed and then incubated with anti-Claudin 5 or anti-ZO-1 antibody and observed under a fluorescence microscope (magnification × 200).