Inhibitive effect of genistein on interleukin-8 expression in cultured human retinal pigment epithelial cells

Recent studies showed that intei-leukin-8 (IL-8) played an important role in retinal neovascularization. In this study, the effects of genistein oil the expression of IL-8 in the arising retinal pigment epithelia-19 cells were studied. The levels of IL-8 protein expression in supernatants were punctually detected by ELISA. When the cells were treated with hypoxia (5% CO2, 95% N-2) IL-8 secretion increased from 0.29 +/- 0.04 to 2.59 +/- 0.42 ng/nd. TO study calcium-dependent IL-8 expression, cells were treated with KCl at 25 mM, norepinephrinc (NE) at 10 nM, and glutantate (Glu) at 1 mu M for 8 h. As a result, the levels of IL-8 protein in supernatants were signficantly increased compared with that in the controls. When the cells are treated with genistein (50, 100, 200 mu M) for 30 min before hypoxia or stimulations by KCl, NE, and Glu, the elevated expression IL-8 protein was all suppressed in a concentration-deliendent manner. These results suggested that suppression of IL-8 expression in retinal pigment epithelial cells might partly account for the inhibitive effect of genistein on retinal neovascularization. (c) 2006 Prou Science. All rights reserved.