MicroRNA-34a通过上调Cdc42和Rac1促进人晶状体上皮细胞衰老和凋亡

目的:观察MicroRNA-34a对人晶状体上皮细胞系SRA01/04衰老和凋亡的影响及作用机制。方法:qRT-PCR检测年龄相关性白内障(ARC)晶状体和透明晶状体上皮细胞中MicroRNA-34a表达水平,采用脂质体转染试剂盒将MicroRNA-34a mimics(过表达组)、MicroRNA-34a inhibitors(抑制组)和空脂质体(对照组)转染至SRA01/04细胞,qRT-PCR检测MicroRNA-34a的表达量;采用β-半乳糖苷酸(SA-β-gal)染色检测转染后细胞的衰老情况。Annexin V-FITC/PI双染色流式细胞仪检测MicroRNA-34a对人晶状体细胞系SRA01/04细胞凋亡的影响;蛋白免疫印迹检测Cdc42、Rac1蛋白的表达。结果:透明晶状体前囊膜组织中MicroRNA-34a的表达量显著低于ARC晶状体前囊膜组织(P<0.05);MicroRNA-34a过表达组、对照组、MicroRNA-34a抑制组SA-β-gal阳性率分别为(87.56±2.34)%、(12.22±2.74)%、(3.45±0.45)%。MicroRNA-34a过表达组明显高于对照组,而MicroRNA-34a抑制组SA-β-gal阳性率明显低于对照组(P<0.05);MicroRNA-34a抑制组、对照组和MicroRNA-34a过表达组的细胞凋亡率分别为(5.87±1.22)%、(12.26±2.14)%、(29.45±3.12)%,MicroRNA-34a抑制组细胞凋亡率明显低于对照组,而MicroRNA-34a过表达组细胞凋亡率明显高于对照组(P<0.05);MicroRNA-34a过表达组中Cdc42和Rac1的表达明显高于对照组(P<0.05),MicroRNA-34a抑制组中Cdc42和Rac1的表达明显低于对照组(P<0.05)。结论:MicroRNA-34a可能通过上调Cdc42和Rac1促进人晶状体上皮细胞衰老和凋亡。

MicroRNA-34a promotes the senescence and apoptosis of human lens epithelial cells by up-regulating Cdc42 and Rac1

·AIM:To observe the effect and mechanism of MicroRNA-34a on senescence and apoptosis of human lens epithelial cell line SRA01/04.·METHODS:MicroRNA-34a expression levels in ARC lens and transparent lens epithelial cells were detected by qRT-PCR.MicroRNA-34a mimics,MicroRNA-34a inhibitors and empty liposome(control group)were transfected into SRA01/04 cells by liposome transfection kit.Annexin V-FITC/PI double staining was used to detect the effect of MicroRNA-34a on the apoptosis of human lens cell line SRA01/04.The expression of Cdc42 and Rac1 protein was detected by western blot.·RESULTS:The expression level of MicroRNA-34a in anterior capsular tissue of transparent lens was significantly lower than that in ARC anterior capsular tissue(P<0.05).The positive rates of SA-β-gal in the MicroRNA-34a mimics group,the control group and the MicroRNA-34a inhibitors group were(87.56±2.34)%,(12.22±2.74)%and(3.45±0.45)%,respectively.The positive rates of SA-β-gal in the MicroRNA-34a mimics group was significantly higher than the control group,while the SA-β-gal positive rate in the MicroRNA-34a inhibitors group was significantly lower than that in the control group(P<0.05).The apoptosis rate of the MicroRNA-34a inhibitors group,control group and MicroRNA-34a mimics group were(5.87±1.22)%,(12.26±2.14)%and(29.45±3.12)%,respectively.The apoptosis rate of the MicroRNA-34a mimics group was significantly higher than that of the control group,while that of the MicroRNA-34a inhibitors group was significantly lower than that of the control group(P<0.05).The expressions of Cdc42 and Rac1 in the MicroRNA-34a mimics group were significantly higher than those in the control group(P<0.05),while the expressions of Cdc42 and Rac1 in the MicroRNA-34a inhibitors group were significantly lower than those in the control group(P<0.05).·CONCLUSION:MicroRNA-34a may promote the senescence and apoptosis of human lens epithelial cells by up-regulating Cdc42 and Rac1.