Department of Integrated Biomedical and Life Sciences, College of Health Science, Korea University, Seoul 02841; 2Cell Therapy Center, Severance Hospital, Seoul 03722, Republic of Korea.
Department of Health and Environmental Science, College of Health Science, Korea University, Seoul 02841, Republic of Korea.
Int J Mol Med. 2017 Nov;40(5):1486-1494. doi: 10.3892/ijmm.2017.3142. Epub 2017 Sep 19.
Mesenchymal stem cells (MSCs) differentiate into multiple lineages and are a promising source of cells for clinical use. Previously, we found that the gene distal‑less homeobox 5 (DLX5) is specifically expressed in MSCs with osteogenic potential. Understanding the mechanism of osteogenesis is necessary for successful bone regeneration using MSCs. The aim of this study was to examine the function of the DLX5 gene in MSCs during osteogenesis (bone development). We analyzed the possible association between DLX5 expression and osteogenesis-, chondrogenesis- and adipogenesis-related gene expression in different cells isolated from bone marrow and cord blood. Differentiation capacity was assessed by observing morphological changes, monitoring gene expression patterns, and staining with Von Kossa, safranin O, and Oil Red O. Suppression of DLX5 expression by means of a small interfering RNA (siRNA) downregulated osteogenic markers and reduced the signs of calcium mineralization. Tanshinone IIA is a known small molecule activator of bone morphogenetic protein (BMP) signaling. Here, we report that induction of DLX5 by tanshinone IIA in MSCs enhanced osteogenic differentiation. In addition, we showed that tanshinone IIA (as a mediator of BMP2 signaling) activates runt-related transcription factor 2 (RUNX2) in MSCs and initiates calcium mineralization during osteogenesis. Taken together, these findings indicate that, in MSCs, DLX5 is a master regulator of osteogenesis. Furthermore, tanshinone IIA may be valuable for stem cell-based therapies of certain bone diseases.
间充质干细胞（MSCs）可分化为多个谱系，是临床应用有前途的细胞来源。此前，我们发现具有成骨潜能的 MSCs 中特异性表达基因远端同源盒 5（DLX5）。了解成骨的机制对于使用 MSCs 成功进行骨再生是必要的。本研究旨在研究 DLX5 基因在成骨过程中（骨发育）对 MSCs 的功能。我们分析了骨髓和脐血分离的不同细胞中 DLX5 表达与成骨、软骨形成和脂肪形成相关基因表达之间的可能关联。通过观察形态变化、监测基因表达模式以及 Von Kossa、番红 O 和 Oil Red O 染色来评估分化能力。通过小干扰 RNA（siRNA）抑制 DLX5 表达下调成骨标志物并减少钙矿化迹象。丹参酮 IIA 是一种已知的骨形态发生蛋白（BMP）信号小分子激活剂。在这里，我们报告丹参酮 IIA 在 MSCs 中诱导 DLX5 增强成骨分化。此外，我们表明丹参酮 IIA（作为 BMP2 信号的介质）激活 MSCs 中的 runt 相关转录因子 2（RUNX2）并在成骨过程中引发钙矿化。总之，这些发现表明，在 MSCs 中，DLX5 是成骨的主调控因子。此外，丹参酮 IIA 可能对某些骨疾病的基于干细胞的治疗有价值。
