【摘要】 目的研究丝胶对糖尿病大鼠血视网膜屏障损伤的改善作用。方法高脂高糖饲料喂养,联合腹腔注射链脲佐菌素构建糖尿病大鼠模型。按照体重将造模成功大鼠随机分为模型组和实验组,每组12只;另取12只正常同周龄大鼠为正常组。大鼠成模后,实验组给予丝胶溶液2. 4 g·kg^-1·d^-1灌胃;另2组均予等体积0. 9%NaCl灌胃,连续35 d。用伊凡思蓝（EB）法测定血视网膜屏障的通透性,用免疫印迹法检测大鼠视网膜中闭合蛋白（Occludin）蛋白的相对表达量,用酶联免疫吸附试验检测视网膜中肿瘤坏死因子-α（TNF-α）的含量。结果正常组、模型组、实验组的EB渗漏量分别是（12. 42±1. 40）,（29. 07±3. 22）和（19. 59±2. 45） ng·mg^-1;这3组的Occludin蛋白的相对表达量（灰度值）分别是0. 91±0. 14,0. 20±0. 04和0. 66±0. 08;这3组的TNF-α含量分别是（113. 31±12. 48）,（212. 09±23. 19）和（156. 05±12. 84） ng·L^-1,模型组与正常组比较,差异均有统计学意义（均P <0. 05）;实验组与模型组比较,差异均有统计学意义（均P <0. 05）。结论丝胶可改善糖尿病大鼠血视网膜屏障损伤,其机制可能与抑制炎症因子的表达有关。更多还原

【Abstract】 Objective To investigate the ameliorating effect of sericin on the blood-retinal barrier breakdown in diabetic rats. Methods The diabetic models were established by feeding high-fat and high-sugar diets and intraperitoneal injection of streptozotocin. Successful model rats were randomized into model group and experimental group with 12 rats for each group,and another 12 normal matched rats served as normal group.The sericin solution 2. 4 g·kg^-1·d^-1 was gavage in the experimental group for 35 d; the other two groups were given intragastric administration of 0. 9% NaCl of equal volume for 35 d. Blood-retinal barrier permeability was detected by evans blue（ EB） method. The expression level of Occludin protein in retinas were detected by Western blot. The content of tumor necrosis factor-α（ TNF-α） in retinas was detected by enzyme-linked immunosorbent assay. Results The amount of EB leakage in normal group,model group and experimental group were respectively（ 12. 42 ± 1. 40）,（ 29. 07 ± 3. 22）,（ 19. 59 ± 2. 45） ng·mg^-1; the relative expression level of Occludin protein in the 3 groups were respectively0. 91 ± 0. 14,0. 20 ± 0. 04 and 0. 66 ± 0. 08; the content of TNF-α in the 3 groups were respectively（ 113. 31 ± 12. 48）,（ 212. 09 ± 23. 19）,（ 156. 05 ± 12. 84） ng·L^-1. Comparison between model group and normal group,the difference of the factors were significant（ all P < 0. 05）; comparison between experimental group and model group,the difference of the factors were significant（ all P < 0. 05）. Conclusion Sericin can improve the blood-retinal barrier breakdown in diabetic rats and the mechanism may be related to inhibition of inflammatory cytokines expression.更多还原