HIF-1 alpha siRNA reduces retinal neovascularization in a mouse model of retinopathy of prematurity

Objective: To explore the effect of HIF-1 alpha specific siRNA expression vector pSUPERH1-siHIF-1 alpha on retinal neovascularization in a mouse model of retinopathy of prematurity (ROP). Methods: Forty-eight newborn C57BL/6J mice were randomly divided into the control and experimental groups (n=24 apiece) to create the model of ROP following the methods described by Smith et al. Twelve days after birth, the experimental group received intravitreal injection with pSUPERH1-siHIF-1 alpha; meanwhile, mice in the control group were injected with empty vectors. The expressions of HIF-1 alpha and vascular endothelia growth factor (VEGF) in the retina were examined by Western blotting in both groups. The differences in the neovascular endothelial cell count were compared based on the FITC-Dextran fluorescence stretched preparation/sections. Results: Compared with the control group, the expressions of HIF-1 alpha and VEGF significantly decreased in the experimental group (P< 0.01). Meanwhile, the number of retinal neovascular endothelial nuclei that had protruded the internal limiting membrane was significantly lower in the experimental group than in control group (P< 0.01). Conclusions: RNA interference targeting HIF-1 alpha can effectively inhibit the retinal neovascularization of ROP.