摘要
目的研究Cyt C和Caspase 3在STZ诱导糖尿病大鼠晶状体上皮细胞(lens epithelial cells,LEC)中的表达,为糖尿病性白内障的发生机制提供新的线索。方法 60只健康雄性SD大鼠分为实验组和对照组,每组各30只,实验组大鼠腹腔注射STZ溶液,对照组腹腔注射柠檬酸缓冲液。每4周监测大鼠血糖并用裂隙灯观察大鼠晶状体混浊情况,12周末取大鼠晶状体前囊膜,应用免疫组织化学和Western blot检测LEC中Cyt C和Caspase 3的表达。结果 12周末实验组大鼠空腹血糖为(24.04±2.40)mmol·L-1,对照组为(5.13±0.37)mmol·L-1。裂隙灯观察显示实验过程中实验组大鼠晶状体出现混浊,而对照组大鼠晶状体均透明。免疫组织化学结果显示:实验组大鼠LEC中Cyt C和Caspase 3表达呈阳性,而对照组则为阴性。Western blot结果显示实验组胞浆内Cyt C含量(0.928 0±0.029 7)大幅度上升,远高于对照组(0.525 0±0.025 8),差异有统计学意义(P<0.05),而实验组大鼠线粒体内Cyt C含量(0.510 5±0.026 4)则大幅度下降,远低于对照组(0.846 0±0.033 5),差异有统计学意义(P<0.05);实验组大鼠LEC中Caspase 3的表达量(0.906 0±0.027 6)明显高于对照组(0.430 5±0.025 2),差异有统计学意义(P<0.05)。结论 STZ诱导糖尿病大鼠LEC中Cyt C由线粒体释放入胞浆且Caspase 3表达量增加,高血糖可能通过刺激LEC释放Cyt C和激活Caspase 3,诱导LEC凋亡从而形成白内障。
Objective To evaluate the expression of Cyt C and Caspase 3 in lens epithelial cells of streptozotocin（ STZ）-induced diabetic rats,and provide new clues for studying the mechanism of diabetic cataract. Methods A total of 60 healthy SD male rats were randomly divided into control group and diabetic group ,30 in each group. The rats in diabetes group were intraperitoneal injected with STZ, and the control group with PBS. The changes of blood glucose were monitored and lens opacity was observed by slit lamp microscope every 4 weeks. Anterior lens capsule were sampled at the end of 12 weeks and the expression of Cyt C and Caspase 3 in lens epithelial cells was detected by immunohistochemistry and Western blot. Results The blood glucose of diabetic group was（24.04 ± 2.40） mmol · L^-1 and that of control group was （5. 13 ± 0.37） mmol · L^-1 at the end of 12 weeks. Slit-lamp examination showed that lens opacification was observed in diabetic group while the lens of control group was transparent at the end of 12 weeks. Immunohistochemistry data suggested that the expression of Cyt C and Caspase 3 in diabetic group was positive whereas the expression in control group was negative. Western blot indicated that the cytosolic contents of Cyt C in diabetic group （0.928 0 ± 0. 029 7 ） were higher than that in control group（0. 525 0 ± 0. 025 8 ）, there was statistical difference（P 〈0.05 ）. And the mitochondrial contents of Cyt C in diabetic group （0.5 10 5 ± 0.026 4） were lower than the control group （0.846 0 ± 0. 033 5 ）, there was statistical difference （ P 〈 0.05 ）. Besides, the expression level of Caspase 3 in dia- betic group （0. 906 0 ± 0. 027 6 ） was significantly higher than that of control group （0. 430 5 ± 0. 025 2）, there was statistical difference （P 〈 0. 05 ）. Conclusion Cyt C is released from the mltochondria into the cytosol and the expression of Caspase 3 in- crease in lens epithelial ceils of STZ-induced diabetic rats, indicating that high glucose may incite the release of Cyt C and activate Caspase 3 to induce the apoptosis of lens epithelial cells which results in cata- ract formation.
出处
《眼科新进展》
CAS
北大核心
2014年第3期228-231,共4页
Recent Advances in Ophthalmology
