Department of Pediatrics, Yongchuan Hospital of Chongqing Medical University, 439 Xuanhua Road, Yongchuan, Chongqing, 402160, China.
Cell Biol Int. 2018 Aug;42(8):913-922. doi: 10.1002/cbin.10813. Epub 2018 Jun 3.
MicroRNAs have potential to modulate the differentiation of stem cells. In previous study, we found that miR-148a was up-regulated in myocardial differentiation of human bone mesenchymal stromal cells (hBMSCs) induced by 5'-azacytidine. However, the role of miR-148a in regulating this process still remains unclear. In this study, we investigated the function and molecular mechanism of miR-148a in myocardial differentiation of hBMSCs. We found that miR-148a was significantly increased while DNA methyltransferase 1 (DNMT1) was significantly decreased in myocardial differentiation of hBMSCs. Then, the dual luciferase reporter assays method indicated that DNMT1 was the direct target of miR-148a. In addition, we showed that up-regulation of miR-148a could enhance myocardial differentiation of hBMSCs, while down-regulation of miR-148a could inhibit myocardial differentiation process. Moreover, knockdown of DNMT1 could block the role of miR-148a in promoting myocardial differentiation of hBMSCs. Finally, MiR-148a acted on methylation level of GATA-4 and knockdown of DNMT1 could block this function. Therefore, our results indicate that miR-148a plays a vital role in regulating myocardial differentiation of hBMSCs by targeting DNMT1.
微小 RNA 具有调节干细胞分化的潜力。在之前的研究中，我们发现 miR-148a 在 5'-氮杂胞苷诱导的人骨髓间充质干细胞（hBMSCs）心肌分化中上调。然而，miR-148a 在调节这一过程中的作用仍不清楚。在本研究中，我们研究了 miR-148a 在 hBMSCs 心肌分化中的功能和分子机制。我们发现 miR-148a 在 hBMSCs 心肌分化中显著增加，而 DNA 甲基转移酶 1（DNMT1）显著减少。然后，双荧光素酶报告基因检测方法表明，DNMT1 是 miR-148a 的直接靶标。此外，我们表明上调 miR-148a 可以增强 hBMSCs 的心肌分化，而下调 miR-148a 可以抑制心肌分化过程。此外，DNMT1 的敲低可以阻断 miR-148a 促进 hBMSCs 心肌分化的作用。最后，miR-148a 作用于 GATA-4 的甲基化水平，而 DNMT1 的敲低可以阻断这一功能。因此，我们的结果表明，miR-148a 通过靶向 DNMT1 在调节 hBMSCs 心肌分化中发挥重要作用。
