Oxidative stress affects retinal pigment epithelial cell survival through epidermal growth factor receptor/AKT signaling pathway

摘要

AIM:To investigate the cross-talk between oxidative stress and the epidermal growth factor receptor(EGFR)/AKT signaling pathway in retinal pigment epithelial( RPE) cells.METHODS:Human RPE cell lines(ARPE-19 cell) were treated with different doses of epidermal growth factor(EGF) and hydrogen peroxide(H2O2).Cell viability was determined by a methyl thiazolyl tetrazolium assay.Cell proliferation was examined by a bromodeoxyuridine(Brd U) incorporation assay.EGFR/AKT signaling was detected by Western blot.EGFR localization was also detected by immunofluorescence.In addition,EGFR/AKT signaling was intervened upon by EGFR inhibitor(erlotinib),PI3 K inhibitor(A66) and AKT inhibitor(MK-2206),respectively.H2O2-induced oxidative stress was blocked by antioxidant N-acetylcysteine(NAC).RESULTS:EGF treatment increased ARPE-19 cell viabili ty and proliferation through inducing phosphorylation of EGFR and AKT.H2O2 inhibited ARPE-19 cell viability and proliferation and also suppressed EGF-stimulated increase of RPE cell viability and proliferation by affecting the EGFR/AKT signaling pathway.EGFR inhibitor erlotinib blocked EGF-induced phosphorylation of EGFR and AKT,while A66 and MK-2206 only blocked EGF-induced phosphorylation of AKT.EGF-induced phosphorylation andendocytosis of EGFR were also affected by H2O2 treatment.In addition,antioxidant NAC attenuated H2O2-induced inhibition of ARPE-19 cell viability through all eviating reduction of EGFR,and phosphorylated and total AKT proteins.CONCLUSION:Oxidative stress affects RPE cell viability and proliferation through interfering with the EGFR/AKT signaling pathway.The EGFR/AKT signaling pathway may be an important target in oxidative stress-induced RPE cell dysfunction.