miR-155对SD大鼠晶状体上皮凋亡抑制作用的初步研究

Preliminary study on the inhibitory effect of miR-155 on lens epithelial apoptosis in SD rats

目的研究微小核糖核酸(miR)-155对高糖诱导的人晶状体囊膜上皮细胞(HLEpiC)和SD大鼠晶状体细胞凋亡的抑制作用。方法晶状体取自正常SD大鼠,晶状体直接进行体外分组培养,晶状体培养组与细胞培养分组相同,培养时间为72 h。低糖(LG)培养基处理HLEpiC至密度为30%～40%,设置不同的培养组来进行加药处理,培养组包括:5.5 mmol/L低糖(LG)培养基组,25 mmol/L甘露醇,25 mmol/L高糖(HG)培养基组,模拟生物体内源的miR-155用药组(mimic),药物对照组(CTm)。用药组分别加入30 nmol/L的miR-155培养48 h。通过Western blot检测不同处理组细胞蛋白和组织凋亡相关蛋白Bcl-2相关X蛋白(Bax)、B细胞淋巴瘤基因2(Bcl-2)以及半胱氨酸天冬氨酸蛋白酶(caspase)家族相关蛋白caspase-3和caspase-9表达量。结果在模拟生物体内源的miRNAs(mimic)的浓度为30 nmol/L时,可以改变高糖引起的晶状体浑浊。30 nmol/L的mimic对HLEpiC的增殖能力有明显的促进作用。与高糖对照组相比,加药组凋亡相关的表达量有明显的变化,促凋亡蛋白Bax以及凋亡效应蛋白caspase-3的表达量明显下调,而抑凋亡蛋白Bcl-2和半胱氨酸天冬氨酸蛋白酶前体蛋白(procaspase-9)表达量明显上调。结论 miR-155通过抑制细胞凋亡的发生来抑制由高糖引起的HLEpiC和SD大鼠晶状体细胞凋亡的发生。

Objective To investigate the inhibitory effect of microRNA(miR)-155 on apoptosis of lens cells induced by high glucose-induced human lens epithelial cells(HLEpiC) and SD rats was studied. Methods The lens was taken from normal SD rats and was directly cultured in vitro . The lens culture group was the same as the cell culture group. The culture time is 72 h. Low-glucose(LG) medium was used to treat HLEpiC to a density of 30% to 40%. Different culture groups were set up for dosing. The culture group included:5.5 mmol/L low-glucose(LG) medium group,25 mmol/L mannitol. The 25 mmol/L high-glucose(HG) medium group mimics the miR-155 drug group(mimic) and the drug control group(CTm). The treatment group was cultured with 30 nmol/L of miR-155 for 48 h. Western blot was used to detect Bcl-2 related protein(Bax),B cell lymphoma gene 2(Bcl-2) and the expression levels of caspase-3 and caspase-9 in different treatment groups. Results When the concentration of miRNAs (mimic) in the simulated organism was 30 nmol/L,the turbidity of the lens caused by high glucose could be changed. The mimic of 30 nmol/L significantly promoted the proliferation of HLEpiC. Compared with the high-glucose control group,the expression of apoptosis-related expression in the drug-added group was significantly changed,and the expression of the pro-apoptotic protein Bax and the apoptosis effector protein caspase-3 were significantly decreased,while the inhibitory protein Bcl-2 and the expression level of caspase proprotein(procaspase-9) was significantly up-regulated. Conclusion miR-155 inhibits the apoptosis of lens cells in HLEpiC and SD rats induced by high glucose by inhibiting the occurrence of apoptosis.