Activated β-catenin induces myogenesis and inhibits adipogenesis in BM-derived mesenchymal stromal cells
Activated β-catenin induces myogenesis and inhibits adipogenesis in BM-derived mesenchymal stromal cells
复制标题
DOI：
10.1080/14653240701508437
复制
发表时间：
2007-01-01
期刊：
影响因子：
4.5
通讯作者：
Li, Y.
中科院分区：
文献类型：
--
作者：
Shang, Y. C.;Zhang, C.;Li, Y.
间充质基质细胞(MSC)一直被认为是治疗退行性肌肉疾病的有吸引力的候选细胞。然而，对MSC向肌细胞分化的分子机制知之甚少。由于Wnt信号通路在胚胎发生和出生后肌肉再生中与肌肉发生有关，我们推测Wnt信号通路可能参与调控MSC的肌源性分化。经G418筛选后，用脂质体将具有构成活性的h-β-连环蛋白(S37A)质粒或对照载体导入RMSC。将转基因的RMSC培养至80%融合，然后在成肌或成脂分化培养液中培养。成肌或成脂后不同时间点的细胞进行光镜、免疫荧光和RT-PCR检测。结果活化的β-连环蛋白在RMSC中的异位表达主要定位于细胞核，并激活转录。稳定的β-连环蛋白过表达可诱导27.1+/-3.91%的RMSC形成长多核细胞，表达MyoD、Mygenin、Desmin和肌球蛋白重链(MHC)，其机制是通过诱导骨骼肌特异性转录因子的表达。此外，激活的β-连环蛋白的过表达通过下调C/EBPα和PPARγ的表达来抑制RMSC的成脂分化。稳定的β-连环蛋白诱导RMSC向肌源性分化的能力可能为其在治疗中的应用奠定基础。
BackgroundMesenchymal stromal cells (MSC) have been thought to be attractive candidates for the treatment of degenerative muscle diseases. However, little is known about the molecular mechanisms governing the myogenic differentiation in MSC. As the Wnt signaling pathway has been associated with myogenesis in embryogenesis and post-natal muscle regeneration, we hypothesized that the Wnt signaling pathway may be involved in governing the myogenic differentiation in MSC.MethodsPrimary MSC were isolated from Sprague-Dawley rats and expanded in proliferation medium. The rMSC were transfected with a constitutively active h beta-catenin (S37A) plasmid or control vector by Lipofectamine followed by G418 selection. The transfected rMSC were grown to 80% confluence and then cultured in myogenic or adipogenic differentiation medium. Cells were characterized by light microscopy, immunofluorescence and RT-PCR at different time points after myogenic or adipogenic introduction.ResultsEctopic expression of activated beta-catenin located primarily in the nucleus and activated transcription in rMSC. Overexpression of stabilized beta-catenin induced 27.1 +/- 3.91 % rMSC forming long multinucleated cells expressing MyoD), myogenin, desmin and myosin heavy chain (MHC via evoking the expression of skeletal muscle-specific transcription factors. In addition, overexpression of activated beta-catenin inhibited the adipogenic differentiation in rMSC through down-regulated expressions of C/EBP alpha and PPAR gamma.DiscussionTo our knowledge, this is the first evidence that activated beta-catenin can induce myogenic differentiation in rMSC. The ability of stabilized beta-catenin to induce myogenic differentiation in rMSC may allow for its therapeutic application.