糖尿病大鼠角膜上皮损伤修复过程中 occludin 的重塑特点

目的：探讨糖尿病（DM）大鼠和正常大鼠角膜上皮修复过程中紧密连接蛋白 occludin 重塑的特点。方法90只 SD 大鼠随机分为 DM组和正常对照组（NC）各45只（DM组均高脂喂养），通过腹腔注射链脲佐菌素（STZ）诱导形成Ⅱ型 DM大鼠模型，于损伤后0 h（未损伤），16、48、72、120 h （每组5只）处死大鼠取角膜。间接免疫荧光染色和 Western blot 法观察 occludin 蛋白在损伤修复过程中的变化。结果DM大鼠角膜上皮损伤愈合率较 NC 组大鼠明显延迟，DM组和 NC 组大鼠角膜上皮 occludin 蛋白在损伤后16、48 h 表达差异有统计学意义（P ＜0．05），在损伤后0、72、120 h 表达差异无统计学意义。结论糖尿病可影响大鼠角膜上皮创伤修复过程中紧密连接蛋白 occludin 蛋白的表达。

Characteristics of reconstituted tight junctions after corneal epithelial wounds in diabetic rats

Objective To investigate the characteristics of reconstituted tight junctions after corneal epithelial wounds in a high-fat diet combined with streptozocin (STZ)-induced rat model of type 2 diabetes mellitus(DM). Methods Ninety Sprague-Dawley male rats were randomly divided into diabetic and normal control groups (n =45 each).A high-fat diet combined with intraperitoneal STZ injection was used to induce type 2 DM.Diabetic and healthy rats were sacrificed before debridement and 16,48,72,and 120 hours afterwards for Western blot and im-munofluorescence.Results Corneal epithelial wound closure rates were decreased in diabetic rats compared with the normal rats.Immunofluorescence and Western blot analysis demonstrated that occludin expression in the corneal epithelium of the diabetic group was weaker compared to the normal group at the 16 and 48 hour time-points after debridement.Conclusion Abnormal occludin expression may contribute to delayed epithelial wound healing in di-abetic corneas.