摘要
背景近年来，随着眼科光学诊疗器械和显微手术应用的增多，各种器械的光源所导致的视网膜损伤等问题倍受关注，研究视网膜光损伤可为临床治疗相关疾病提供参考。目的研究小鼠光损伤后视网膜色素上皮（RPE）层基质金属蛋白酶2（MMP-2）、MMP-9表达的变化，探讨促红细胞生成素（EPO）对小鼠视网膜光损伤的治疗作用及其相关机制。方法将52只SPF级BALB／c小鼠采用抽签法随机分为正常对照组4只、单纯光照组24只和EPO预处理组24只，后两组小鼠在自制光照箱内用6000lx弥散白光照射4h以建立光损伤动物模型。单纯光照组接受6000lx白光照射4h，EPO预处理组小鼠腹腔注射rhEPO5000U／kg（商品单位）后，接受6000lx白光照射4h。光照后6、12、36、72、96h和7d采用免疫组织化学法检测各组小鼠RPE中MMP-2和MMP-9的表达。结果单纯光照组小鼠视网膜组织病理学改变出现早且明显，光照后RPE细胞出现不同程度的水肿和结构紊乱，且随着光照后时间的延长，形态异常的细胞数增加，但EPO预处理组在光照后7d未发现类似改变。免疫组织化学法检测显示，正常BALB／c小鼠RPE层MMP-2低表达，单纯光照36h后，RPE层可观察到大量MMP-2阳性表达细胞，但同一时间点EPO预处理组阳性表达量（A值）明显下降。3个组和不同时间点MMP-2的表达量差异均有统计学意义（F分组=3．68，P=0．04；F时间=9．13，P=0．00）。MMP-9免疫组织化学法检测显示，正常RPE层中未见MMP-9的阳性表达，单纯光照6h后，MMP-9开始表达，12h时达高峰并维持高表达状态，96h后表达量开始下降；EPO预处理组MMP-9表达趋势同单纯光照组，但各时间点MMP-9的表达量均较单纯光照组减少。3个组和不同时间点MMP-9的表达差异均有统计学意义（F分组==3．61，P=0．04；F时间=16．91，P=0．00）。结论MMP-2、MMP-9在视网膜光损伤过程中发挥着重要作用，推测EPO可能通过抑制MMP-2、MMP-9的表达发挥对视网膜的保护作用。
Background Increase in ophthalmic leads to retinal photochemical damage and other problems optical medical instruments and microsurgical applications delivery of a variety of devices, so the in-depth study and understanding of its pathogenesis after retina light damage can provide a reference for the clinical treatment of related diseases. Objective This study was to investigate the therapeutic effect and relative mechanism of erythropoietin （EPO） on mouse retina pbotic injury by studying the expression of matrix metalloproteinases-2 （MMP-2）and MMP-9. Methods Fifty-two SPF BALB/c mice were randomized into normal control group,simple llght-induced group and EPO pretreatment group by balloting method. The mice of simple light-induced group and EPO pretreatment group were continuously irradiated with 6000 lx diffuse light for 4 hours in a home-made box to establish the models of light- induced damage;while recombinant human EPO （rhEPO）of 5000 U/kg was intraperitoneally injected prior to the light exposure in the EPO pretreatment group. The expressions of MMP-2 and MMP-9 were examined at 6,12,36,72,96 hours and 7 days following light-exposure by immunohistochemistry. Results Edema and structural disorder of RPE cells appeared in the simple light-induced group after light-exposure and aggravated with lapse of light-exposure time,but no similar change was seen until 7 days in the EPO pretreatment group. The immunohistochemistry findings showed that the expression of MMP-2（A value）in RPE cells was less in the normal mice. However,a large quantity of positive cells appeared in RPE layer 36 hours after light-exposure. Compared with the simple light-induced group,the positive expression of MMP-2 protein in EPO pretreatment group was significantly decreased, showing statistically significant differences among these three groups and different time points（ Fgroup = 3.68, P = 0.04; Ftime = 9. 13,P=0.00）. There was hardly any MMP-9 expression in the retina of the normal mice. In simple light-induced group,a few of positive cells appeared in RPE layer 6 hours after light-exposure and reached its peak 12 hours following light- exposure. The gradually down-regulation of MMP-9 expression happened 96 hours later following light-irradiation. The expression tendency of MMP-9 in EPO pretreatment group was similar to the simple light-induced group. Significant differences in expressions of MMP-9 were found among different groups and time points （ Fgroup = 3.61, P = 0.04 ; Ftime = 16.91 ,P=0.00）. Conclusions MMP-2 and MMP-9 may be involved in the mechanism of retina photic injury by down-regulating the expression of MMP-2 and MMP-9 in RPE cells.
出处
《中华实验眼科杂志》
CAS
CSCD
北大核心
2012年第11期999-1003,共5页
Chinese Journal Of Experimental Ophthalmology
基金
国家自然科学基金项目（30572010）
