Suppression Of Choroidal Neovascularization By Endostar In Rats

Background/aims:Choroidal neovascularization (CNV) is common in various retinal and chorioldal diseases and can cause severe and irreversible visual loss. Our previous works suggested that Endostar, a novel recombinant endostatin, can inhibit proliferation and migration of choroid-retinal endothelial cells. This study aims to evaluate the effect of Endostar in laser-induced CNV rats.Method:CNV was induced by532laser coagulation. Endostar or PBS was administered intravitreally every two days after laser application. At day14, fluorescence angiography (FA) was performed in rat models. CNV area and maximal thickness were measured on choroid flatmounts and sections. Real-Time Polymerase Chain Reaction (RT-PCR) was used and then vascular endothelial growth factor (VEGF) was further verified by western blot analysis. Results:CNV incidence and leakage had prominent reduced in the Endostar group on FA (50.3%vs75.8%, p<0.001). Mean CNV area and maximal thickness in Endostar group were decrease significantly in Endostar group (p<0.05). VEGF, hypoxia-inducible factor1alpha (HIF-1α), chemokine (C-X-C motif) ligand1(CXCL1) were markedly reduced in Endostar group confirmed by Real Time-PCR (p<0.05). Down-expression of VEGF in Endostar group were also vertified by western blot.Conclusion:Intravitreal Endostar treatment contributes to CNV suppression in rat model. This activity can be largely ascribed to down-regulation of VEGF. HIF-la and CXCL1also participate in the complicated network.