中文摘要：

目的检测microRNA-33（miR-33）在过氧化氢（H2O2）诱导的NIH/3T3细胞衰老模型中的表达水平,并进一步研究过表达miR-33对H2O2诱导的细胞衰老的影响。方法 H2O2处理小鼠胚胎成纤维细胞系NIH/3T3后,利用SA-β-半乳糖苷酶染色以及Western blot检测p16蛋白的表达验证H2O2诱导NIH/3T3细胞的衰老表型;利用荧光定量PCR检测miR-33在H2O2诱导的衰老NIH/3T3细胞中的表达;利用RNAimax转染miR-33模拟物Agomir-33及其对照Agomir NC至NIH/3T3细胞,研究过表达miR-33对H2O2诱导的NIH/3T3细胞衰老表型的影响。结果 miR-33在H2O2诱导的NIH/3T3细胞衰老模型中显著下调,但过表达miR-33并不显著影响H2O2诱导的NIH/3T3细胞衰老。结论 MicroRNA-33在过氧化氢诱导的细胞衰老表型中并不发挥显著作用。

英文摘要：

Objective We herein attempted to detect the expression of microRNA- 33（ miR- 33） in the H2O2- induced premature senescence of NIH /3T3 cells,and further probed into the role of miR- 33 on H2O2- induced premature senescence by ectopic expression of miR- 33 in NIH /3T3 cells. Methods The senescence- associated β- galactosidase staining and the detection of molecular senescencent marker,p16 expression levels by western blot were performed to confirm the premature senescence in NIH /3T3 cells after H2O2treatment; Real- time q PCR was utilized to detect the miR- 33 expression in H2O2- induced premature senescence of NIH /3T3 cells; To investigate into the function of miR- 33 on H2O2- induced premature senescence,miR- 33 mimics（ Agomir33） or the negative control（ Agomir NC） was trasfected into the NIH /3T3 cells by lipofectamine RNAimax. Results miR- 33 was dramatically down- regulated in the H2O2- induced premature senescence of NIH /3T3 cells. Nonetheless,forced expression of miR-33 exhibited no significant effect on H2O2- induced premature senescence. Conclusion MicroRNA- 33 might not play an important role in the H2O2- induced premature senescence.