摘要
目的探讨微管相关蛋白1轻链3(MAP1-LC3)在糖尿病大鼠视网膜中的表达及其意义。方法将24只雄性SD大鼠随机分为3组:正常对照组(C组,n=8),糖尿病组(D组,n=8),非诺贝特干预组(F组,n=8)。利用10 g/L链脲佐星(STZ)建立糖尿病大鼠模型。成模后给予药物干预,并在第4周末时取出大鼠眼球。将眼球置于中性甲醛固定后作免疫组织化学检测,分离视网膜抽提蛋白,采用免疫印迹技术检测视网膜组织中LC3蛋白的表达。采用TUNEL法测定4周时大鼠视网膜各层细胞凋亡情况。结果成功构建糖尿病大鼠模型。苏木素-伊红(HE)染色显示3组大鼠视网膜各层细胞无明显改变。3组大鼠视网膜LC3蛋白均有表达,免疫组织化学和Western印迹法检测结果一致。糖尿病大鼠视网膜中有LC3蛋白的表达,且明显高于正常对照组。LC3Ⅱ/LC3Ⅰ比值,C组明显低于D组和F组(P<0.05),F组高于D组(P<0.05),说明非诺贝特干预后,F组LC3Ⅰ向LC3Ⅱ的转化表达增加。免疫组织化学与Western印迹法结果一致。建模4周,仅D组见极少量细胞质呈绿色的凋亡阳性细胞。结论糖尿病大鼠视网膜自噬增加,非诺贝特能增强自噬,且未见明显细胞凋亡。在糖尿病性视网膜病变中,自噬作为保护机制,早于细胞凋亡的发生。
Objective To explore the expression and significance of microtubule-associated protein 1 light chain 3 （ MAP1-LC3 ） in the retina of early stage diabetic rats. Methods Twenty-four SD rats were randomly divided into the control group（ Group C, n =8 ）, streptozotocin （STZ） group （Group D, n = 8 ） and STZ ＋ fenofibrate group （ Group F, n = 8）. At the end of the 4th week, all rats were sacrificed, and their eyeballs were harvested. The retinas were tested by hemotoxylin-eosin （HE） staining, the protein expression of LC3 were tested by Western blot and immunohistochemistry. Terminal-deoxynucleoitidyl transferase mediated nick end labeling （TUNEL） was performed to observe the apoptosis of retina cells in all rats. Results Diabetic rat model was successfully established. HE staining showed no obvious pathologic changes in retina among the three groups. Western blot test showed that the ratio of LC3 I1/LC3 I in retina was significantly increased in Group D and Group F compared with Group C at the end of the 4th week（ P 〈 0.05 ）. The immunohistochemical test of LC3 showed the consistent results as Western blot. Retina cells had no obvious apoptosis in all three groups. Conclusions Autophagy was increased in early stage diabetic rats. Fenofibrate increased autophagy in diabetic rats. A protective mechanism, autophagy, occurred before cell apoptosis in diabetic retinopathy. （ Chin J Ophthalmol and Otorhinolaryngol,2017,17 ： 10-15）
出处
《中国眼耳鼻喉科杂志》
2017年第1期10-15,共6页
Chinese Journal of Ophthalmology and Otorhinolaryngology
