腺病毒载体介导的色素上皮衍生因子对大鼠视网膜缺血再灌注损伤的保护作用

目的:观察重组腺病毒介导的色素上皮衍生因子(Ad-PEDF)对大鼠视网膜缺血再灌注损伤的保护作用及机制。方法:选用健康大鼠96只,随机分为正常组、缺血再灌注组、缺血再灌注+Ad-CMV组,缺血再灌注+Ad-PEDF组,以前房加压的方法制备大鼠视网膜缺血再灌注模型,缺血再灌注+Ad-CMV组,缺血再灌注+Ad-PEDF组分别玻璃体腔注射Ad-CMV或Ad-PEDF1μL(滴度3.8×109/PFU),每组按照时间点12,24,72,168h,为4亚组,光学显微镜观察视网膜组织切片情况,并测量视网膜内层厚度及神经节细胞层神经节细胞数量。以TUNEL方法观察大鼠视网膜神经节细胞凋亡情况。结果:Ad-PEDF组视网膜内层厚度均超过缺血组及缺血+Ad-CMV组,Ad-PEDF组神经节细胞数目多于缺血组及Ad-CMV组,Ad-PEDF组视网膜神经节细胞凋亡细胞少于缺血组及Ad-CMV组,凋亡程度减轻,上述差异均具有显著性(P<0.05)。结论:腺病毒介导的色素上皮衍生因子玻璃体腔注射能够恢复大鼠视网膜缺血再灌注损伤所致的视网膜内层厚度降低,神经节细胞密度减少,具有保护作用。

Protective effect of adenovirus-mediated pigment epithelium-derived factor on retinal ischemia-reperfusion injury in rats

AIM:To examine the protective effects and mechanism of adenovirally delivered pigment epithelium derived factor (Ad-PEDF) on experimental retinal ischemia reperfused injury (RIR) in rats.METHODS: RIR was induced in 96 adult rats by increasing intraocular pressure (IOP) via an intracameral infusion. All of the rats were divided into four groups: normal control group; RIR group; RIR Ad-PEDF treatment group and RIR Ad-CMV control group. The groups were subdivided into groups of 12 hours, 24 hours, 72 hours and 168 hours after reperfusion randomly. The neuroprotective effects of Ad-PEDF were evaluated by determining the preservation of the inner retina thickness and the cell counts in the retinal ganglion cell layer by HE staining method. The levels of retinal ganglion cell (RGC) apoptosis were measured using the TdT-dUTP terminal nick-end labeling (TUNEL) method.RESULTS: Significant ameliorative effect on the thickness of the inner retina was observed in Ad-PEDF treated eyes. More cells in the RGC layer were retained in the Ad-PEDF treated eyes than untreated eyes. There were fewer apoptotic cells in the RGC layer in Ad-PEDF injected eyes than in untreated eyes. These results were statistically significant (P<0.05, respectively).CONCLUSION: Intravitreal injection of Ad-PEDF protected the inner retina and the cells in the RGC layer of eyes after ischemia-reperfusion injury. Intravitreal injection of Ad-PEDF moderately protected rat retina from ischemia-reperfusion injury possibly by preventing apoptosis in retinal cells.