氧诱导视网膜新生血管模型中基质细胞衍生因子1的表达及机制研究

目的: 观察基质细胞衍生因子1(SDF-1)在氧诱导视网膜新生血管(OIR)模型中的表达情况,并初步研究其在OIR模型中的促新生血管生长机制。方法: 30只C57BL/6J新生小鼠随机分为2组。其中15只小鼠置于氧浓度为75%的容器内饲养5 d,再转移至正常空气下饲养5 d,作为高氧诱导组;另15只小鼠一直在正常空气中饲养,作为正常对照组。免疫组织化学方法检测视网膜SDF-1、CD14蛋白的定位及含量,real-time PCR法检测视网膜SDF-1 mRNA的表达。结果: 与正常对照组相比,高氧诱导组突破视网膜内界膜的内皮细胞核数目明显增多(P<0.01),血管分支减少,大血管扩张、迂曲。两组小鼠视网膜神经上皮均可见SDF-1和CD14阳性染色,但高氧诱导组的SDF-1和CD14含量明显高于正常对照组(均P<0.01)。并且视网膜SDF-1与CD14的蛋白含量存在正相关(r=0.898,P<0.01)。视网膜SDF-1 mRNA表达在高氧诱导组也明显高于正常对照组(P<0.01)。结论: OIR模型小鼠视网膜SDF-1表达增高,其促新生血管功能可能与CD14⁺细胞有关。

Expression of stromal cell-derived factor 1 in retinas with oxygen-induced retinal neovascularization

AIM: To observe the expression of stromal cell-derived factor 1(SDF-1) in oxygen-induced retinopathy (OIR) model.METHODS: Thirty C57BL/6J newborn mice were randomly divided into 2 groups: 15 mice in oxygen-induced group were exposed to 75% oxygen for 5 days and to room air for another 5 days to establish the model of OIR, and the other 15 mice were kept in room air as control group. The mRNA expression of SDF-1 was determined by real-time RT-PCR. Retinal proteins of SDF-1 and CD14 were determined by immunohistochemistry.RESULTS: The numbers of the endotheliocyte nuclei in new vessels extending from retina to vitrous were lower in control group than that in oxygen-induced group (P<0.01). Positive immunohistochemical staining for SDF-1 and CD14 was found in both group, and significant differences of SDF-1 and CD14 between oxygen-induced group and control group (both P<0.01) were observed. A strong correlation of retinal content of CD14 with the expression of SDF-1 was found (r=0.898, P<0.01). The difference of SDF-1 mRNA expression between oxygen-induced group and control group (P<0.01) was significant.CONCLUSION: The expression of SDF-1 is increased in the retinas of OIR mice. Involvement of CD14⁺ cells is a possible mechanism of SDF-1 in promoting neovascularization.