CCN1在氧诱导小鼠视网膜新生血管形成中的表达及意义

目的:研究富含半胱氨酸蛋白61(CCN1/Cyr61)在氧诱导小鼠视网膜新生血管(retinal neovascularization,RNV)中的表达及意义,探讨特异性抑制CCN1对RNV形成的抑制作用。方法:取C57BL/6J小鼠200只,随机分为对照组、高氧组、高氧对照组和CCN1治疗组,每组各50只。高氧对照组和CCN1治疗组分别玻璃体腔内注射空载体质粒和CCN1siRNA表达质粒。ADP酶视网膜铺片观察视网膜血管形态,HE染色计数突破视网膜内界膜的新生血管内皮细胞核数,免疫组织化学、Western blot和RT-PCR法检测CCN1蛋白及mRNA的表达情况。结果:高氧组和高氧对照组视网膜可见大片无灌注区和大量突破内界膜的新生血管内皮细胞核(25.25±1.26个;23.12±1.16个),CCN1治疗组较高氧组和高氧对照组的无灌注区及新生血管内皮细胞核数(8.47±1.15个)明显减少。高氧组和高氧对照组较对照组相比,CCN1蛋白及mRNA表达显著增高,CCN1治疗组较高氧组和高氧对照组显著减弱,均有统计学意义(均为P<0.05)。结论:CCN1的异常表达可能与RNV形成密切相关,特异性抑制CCN1能有效抑制RNV的形成,为预防和治疗ROP提供新的思路及对策。

Expression and significance of CCN1 in oxygen-induced retinal neovascularization of mice

AIM: To explore the expression and significance of cysteine-rich 61(CCN1/Cyr61)in oxygen-induced retinal neovascularization(RNV)of mice and study the inhibition effect of CCN1 specific siRNA on RNV.

METHODS: Two hundred healthy C57BL/6J mice were chosen and randomly divided into control group, hyperxia group, hyperxia control group and CCN1 treated group, with 50 mice in each group. The hyperxia control group was treated with vector plasmids by intravitreal injection. The CCN1 treated group received CCN1 siRNA recombinant plasmids by intravitreal injection. Adenosine diphosphate-ase(ADPase)stained retina flat-mounts was performed to assess the retinal vascular profiles, HE staining was applied to count the number of vascular endothelial cell nuclei breaking through the internal limiting membrane, protein and mRNA level expression of CCN1 were measured by immunohistochemistry, Western blot and RT-PCR.

RESULTS: There were large nonperfusion area and a large number of vascular endothelial cell nuclei breaking through the internal limiting membrane(25.25±1.26; 23.12±1.16)in the hyperxia group and the hyperxia control group. Regions of nonperfusion and vascular endothelial cell nuclei(8.47±1.15)were decreased in the CCN1 treated group compared to the hyperxia group and the hyperxia control group. Compared with the control group, there were high protein and mRNA expression of CCN1 in the hyperxia group and the hyperxia control group. The expression of CCN1 protein and mRNA were decreased in the CCN1 treated group compared with the hyperxia group and hyperxia control group(all P<0.05).

CONCLUSION: The abnormal expression of CCN1 has close relation with RNV. The development of RNV can be markedly inhibited by RNA interference targeting CCN1, which, we believe, will provide new molecular targets and a rationale for clinical developing new strategy for ROP therapy.