Hydrogen peroxide induces expression and transcription of erythropoietin in the human retinal pigment epithelium cells

Abstract

To investigate the expression of erythropoietin (EPO) in human fetal retinal pigment epithelium (hfRPE) cells exposed to oxidative stress induced by hydrogen peroxide (H(2)O(2)) and to study the mechanisms. The hfRPE cells were isolated, cultured and identified. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) of the hfRPE cells were examined. The changes of level of mRNA and protein of EPO in hfRPE cells exposed to oxidative stress were measured by semi-quantitative RT-PCR and immunocytochemical staining techniques. H(2)O(2) could increase the content of MDA and inhibit the activity of SOD in hfRPE cells. RT-PCR detected a significant increase of EPO mRNA level in cultured hfRPE cells exposed to oxidative stress. The level of EPO mRNA in the hfRPE cells reached a peak when exposed to 600 micromol/L H(2)O(2), then decreased after exposing to 800 micromol/L H(2)O(2). The immunocytochemical study detected that the changes of the level of EPO protein were similar to that of EPO mRNA. Oxidation stress by exposed to H(2)O(2) induces significant increase of EPO expression of hfRPE cells. Expression of EPO may be related to the survival and tolerance of hfRPE cells.