EphB4/EphrinB2对糖尿病视网膜病变大鼠视网膜新生血管生成的影响

目的探讨EphB4/EphrinB2对糖尿病视网膜病变(diabetic retinopathy,DR)大鼠视网膜新生血管生成的影响。方法取60只健康雄性SD大鼠,随机分为模型组、干预组和对照组,每组20只。模型组建立大鼠DR模型;干预组建立DR模型并于玻璃体内注射2μL sEphB4;对照组建立DR模型并于双眼玻璃体内注射2μL生理盐水。分别用ADP酶染色观察视网膜新生血管形态和分布,免疫荧光双标检测EphB4/EphrinB2蛋白的表达,Western blot检测EphB4蛋白的表达。结果各组视网膜新生血管观察结果显示,模型组和对照组大鼠视网膜毛细血管扩张、迂曲,出现微血管瘤并可见大量紊乱的新生血管,干预组视网膜血管形态接近正常,新生血管少见。模型组和对照组视网膜组织EphB4和EphrinB2蛋白呈高表达,干预组的EphB4和EphrinB2的蛋白表达量明显少于模型组和对照组,这说明sEphB4可以有效地抑制视网膜组织EphB4和EphrinB2蛋白的表达。模型组和对照组视网膜组织EphB4蛋白表达量较高,干预组DR大鼠视网膜组织中EphB4蛋白表达量明显低于模型组和对照组。整...

Effect of EphB4/EphrinB2 on neovascularization in rats with diabetic retinopathy

Objective　To study the effect of Ephrin type-B receptor 4(EphB4)/EphrinB2 on retinal neovascularization in rats with diabetic retinopathy(DR).Methods　Sixty healthy male SD rats were divided into 3 groups randomly:model group, intervention group and control group, with 20 rats in each group. DR model was established in the model group, DR model was established in the intervention group and 2 μL sEphB4 was injected into vitreous cavity, while in the control group，DR model was established and 2 μL of normal saline was injected into the vitreous cavity of both eyes. The retinal vessels were observed with ADP enzyme staining, and the expression of EphB4/EphrinB2 protein in retina was observed with immunofluorescence. Quantitative analysis of EphB4 protein was performed by Western blot.Results　The observation results of retinal neovascularization in each group showed that the retinal capillaries of the model group and the control group were dilated, tortuous, microvascular tumors and a large number of disordered neovascularizations were seen in the rats in the model group and the control group. The retinal tissues of the model group and control group showed high expression of EphB4 and EphrinB2. The protein expression levels of EphB4 and EphrinB2 in the intervention group was significantly lower than those of the model group and control group, showed that sEphB4 effectively inhibited the expression of EphB4 and EphrinB2 proteins in retinal tissues. The expression of EphB4 protein in the retinal tissue of the model group and the control group was higher, and the expression level of EphB4 protein in the retinal tissue of the intervention group was significantly lower than that in the model group and the control group. The results of the integrated optical density analysis showed that the ratio of optical density of EphB4 protein to the internal reference β-actin in the intervention group was 0.12±0.02, which was significantly different from the ratio of the model group (0.76±0.04) and the ratio of control group (0.68±0.05, both P<0.01), while the difference between the model group and the control group was not statistically significant (P=0.08).Conclusion　over-expression of EphB4/EphrinB2 is closely related to the proliferation of retinal neovascularization. sEphB4 can target the blockade of EphB4 and effectively reduce the formation of retinal neovascularization.