microRNA-21对机械力作用下小鼠L929细胞增殖和凋亡的影响

目的探讨miRNA-21对机械力作用下小鼠成纤维细胞系L929细胞的增殖和凋亡的影响。方法细胞培养与转染将L929细胞接种于细胞培养基(RPMI-1640)中,实验选用对数生长期长势良好的细胞,将细胞浓度调整为1×10^5/m L,接种于无菌的6孔板中,并分为阴性对照组(转染随机序列)、空白组及miRNA-21过表达组。miRNA-21过表达组采用miRNA-21模拟物(miRNA-21mimics)上调小鼠成纤维细胞内miRNA-21的表达。使用四点弯曲细胞力学加载系统对两组细胞分别进行力学加载,建立压力性尿失禁(stress urinary incontinence,SUI)细胞模型,加力大小为0、5333μstrain(4 mm),加载时间设定为4 h。使用CCK-8法检测各组细胞增殖,流式细胞仪检测各组细胞凋亡。结果与对照组及miRNA-21过表达组相比,加力组的细胞增殖活性明显下降,细胞凋亡率明显升高,差异有统计学意义(P<0.001);而与加力组相比,miRNA-21过表达+加力组的细胞增殖活性显著上升,细胞凋亡率明显下降,差异有统计学意义(P<0.001)。结论miRNA-21模拟物可通过上调小鼠成纤维细胞中miRNA-21的表达,影响机械力作用下小鼠成纤维细胞的增殖和凋亡,可能成为SUI生物治疗的新靶点。

Effect of microRNA-21 on the proliferation and apoptosis of mouse L929fibroblast after mechanical strain

Objective To determine the effect of microRNA-21 mimics on the proliferation and apoptosis of mouse fibroblasts cell line L929 after mechanical strain. Methods Cultured mouse fibroblasts were divided into two groups: the control group and miRNA-21-overexpression group. In the miRNA-21-overexpression group,miRNA-21 mimics were used to activate the expression of miRNA-21. Cells were stretched by four-point bending system for 0、5333 μ strain( 4 mm) for the frequency of 0. 1 Hz and 4 hours.The cell proliferation was detected by CCK-8,The apoptosis rate were measured by flow cytometry. Results Compared with control group and miRNA-21-overexpression group,the cell proliferation activity was declined( P < 0. 001) and the apoptosis rate was significantly increased( P < 0. 001) in mechanical strain group;while the cell proliferation activity was remarkably enhanced( P <0. 001) and the apoptosis rate was significantly decreased( P < 0. 001) in miRNA-21-overexpression + mechanical strain group when compared with mechanical strain group. Conclusion The miRNA-21 mimics play an important role in the proliferation and apoptosis of mouse fibroblast after mechanical strain through up-regulating miRNA-21,which may be a promising target for biotherapy of stress urinary incontinence( SUI).