National Cell Bank of Iran, Pasteur Institute of Iran, National Cell Bank of Iran, Tehran, Iran.
Cell Biol Int. 2012 Jul;36(7):669-75. doi: 10.1042/CBI20110400.
Both fetal and adult skeletal muscle cells are continually being subjected to biomechanical forces. Biomechanical stimulation during cell growth affects proliferation, differentiation and maturation of skeletal muscle cells. Bone marrow-derived hMSCs [human MSCs (mesenchymal stem cells)] can differentiate into a variety of cell types, including skeletal muscle cells that are potentially a source for muscle regeneration. Our investigations involved a 10% cyclic uniaxial strain at 1 Hz being applied to hMSCs grown on collagen-coated silicon membranes with or without IGF-I (insulin-like growth factor-I) for 24 h. Results obtained from morphological studies confirmed the rearrangement of cells after loading. Comparison of MyoD and MyoG mRNA levels between test groups showed that mechanical loading alone can initiate myogenic differentiation. Furthermore, comparison of Myf5, MyoD, MyoG and Myf6 mRNA levels between test groups showed that a combination of mechanical loading and growth factor results in the highest expression of myogenic genes. These results indicate that cyclic strain may be useful in myogenic differentiation of stem cells, and can accelerate the differentiation of hMSCs into MSCs in the presence of growth factor.
胎儿和成体的骨骼肌细胞持续受到生物力学力的作用。细胞生长过程中的生物力学刺激会影响骨骼肌细胞的增殖、分化和成熟。骨髓来源的 hMSCs（间充质干细胞）可以分化为多种细胞类型，包括骨骼肌细胞，这可能是肌肉再生的来源。我们的研究涉及在胶原包被的硅膜上培养 hMSCs，施加 10%的循环单轴应变，频率为 1 Hz，持续 24 小时，同时或不施加 IGF-I（胰岛素样生长因子-I）。加载后细胞形态学研究的结果证实了细胞的重排。比较试验组之间的 MyoD 和 MyoG mRNA 水平表明，机械加载本身可以启动成肌分化。此外，比较试验组之间的 Myf5、MyoD、MyoG 和 Myf6 mRNA 水平表明，机械加载和生长因子的组合导致最高的成肌基因表达。这些结果表明，循环应变可能有助于干细胞的成肌分化，并可以在生长因子存在的情况下加速 hMSCs 向 MSC 的分化。
