miRNA-29b调控骨髓间充质干细胞来源的软骨细胞肥大化的作用研究

Effect of miRNA-29b on regulating hypertrophy of bone marrow mesenchymal stem cell-derived chondrocytes

目的探讨miR-29b在骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)分化为软骨细胞时,对细胞肥大化进程的调控作用。方法培养BMSCs并进行软骨细胞肥大化方向的诱导,检测软骨细胞标志基因Ⅱ型胶原(ColⅡ)、肥大化细胞标志基因Ⅹ型胶原(ColⅩ和Runx2),并用特异性染色法确定细胞肥大化诱导成功,再检测miR-29b在转录水平的表达情况。然后将实验分为miR-29b过表达(miR-29b mimics)和miR-29b抑制(miR-29b抑制剂)两组,每组分别设置空白对照组,分别检测两处理组中上述软骨细胞和肥大化细胞相关标志的表达变化。结果 miR-29b过表达组中,ColⅡ表达与对照组相比显著降低(P<0.05),ColⅩ和Runx2表达显著升高(P<0.05);而miR-29b抑制组中,ColⅡ的表达与对照组相比显著升高(P<0.05),ColⅩ和Runx2显著降低(P<0.05)。结论miR-29可以有效促进BMSCs向肥大化的软骨细胞分化,而抑制miR-29b可降低BMSCs来源的软骨细胞的肥大化。

Objective To investigate the effect of miR-29b on regulating cell hypertrophy in the differentiation of bone marrow mesenehymal stem cells （BMSCs） into chondroeytes. Methods BMSCs were cultured and induced into hypertrophic chondrocytes. Collagen type ]I （ Col ]] , marker of chondrocytes） and collagen type X （Col X, marker of hypertrophic chondrocytes ） were detected by qRT-PCR. Safranin O staining was employed to confirm the hypertrophic state of the chondroeytes, and then the expression of miR- 29b in the transcriptional level was detected by qRT-PCR. In the experiment, the BMSCs were divided into the following groups： miR-29b over-expression group, miR-29b inhibition group, over-expression negative control group and inhibition negative control group. The expression of the related markers in the 4 groups were detected. Results In the miR-29b mimics group, the expression of Col Ⅱ was decreased significantly compared with the control group （ P 〈 0. 05 ） , while the expression of Col X and Runx2 was significantly increased （P 〈 0. 05 ）. However, the expression of Col Ⅱ in the miR-29b inhibition group was significantly higher than that in the control group （ P 〈 0. 05 ） , while that of Col X and Runx2 was significantly reduced （P 〈 0. 05）. Conclusion MiR-29 can effectively promote hypertrophy of BMSC-derived chondrocytes, and the inhibition of miR-29 can stabilize the phenotvDe of BMSC-derived chondrocvtes.