Inhibitory effect of cathepsin B-RNAi-lentivirus on mouse retinal neovascularization / 中华实验眼科杂志

ABSTRACT

Background Retinal neovascularization disease is a group of threatening-vision eye diseases.Researches showed that cathepsin B is involved in angiogenesis.Exploring a drug which inhibit retinal blood vessels will provide the basis for the molecular mechanism of these diseases.Objective This study was to investigate the inhibitory role of cathepsin B-RNAi-lentivirus on retinal angiogenesis.Methods Sixty 7-day-old C57BL/6J mice were raised together with maternal mice in the closed box with the oxygen concentration of (75-2)％ for 5 days to establish the retinal angiogenesis mouse models.The mice were then taken into the normal air environment for continuous raise and were randomized into 3 groups.NC-GFP-LV of 1 μl and the equal volume of cathepsin B-RNAi-lentivirus was intravitreously injected respectively in 40 eyes in the control group and the gene treatment group,and no drug was administered in the 40 eyes of the model group.The mice were sacrificed and retinas were obtained.Expression of cathepsin B protein in the retina was detected by Western blot assay (cathepsin B/β-actin).Real-time PCR was used to detect and compare the expression level of cathepsin B mRNA (2△△Ct).FITC-dextran was used to perform heart infusion for the retinal stretched preparation 5 days after intravitreously injection.Retinal neovascularization was examined by fluorescent angiography.Results The expression level (2-△△Ct) of cathepsin B mRNA was 0.74 ±0.12 in the gene treatment group,showing a significant decline in comparison with 1.66±0.17 and 1.58±0.29 in the model group and control group (q--0.746,1.588,P＜ 0.01).The expression level of cathepsin B protein (cathepsin B/β-actin) in the retina was 0.64±0.06,0.93±0.09 and 0.96±0.09 respectively in the gene treatment group,model group and control group,indicating a significant reduce in the gene treatment group (q =0.637,0.894,P＜0.01).Distorted vessels were seen in the mice retinas of the model group with more branches and vascular anastomosis,and fluorescine leakage was exhibited under the fluorescence microscope.However,the vessels were regular with less branches and angiogenesis.Conclusions Cathepsin B-RNAi-lentivirus can effectively inhibit oxygen-induced retinal angiogenesis in mouse.