Karadas Ozge, Mese Gulistan, Ozcivici Engin
Department of Bioengineering, Rm A210, Izmir Institute of Technology, Urla, Izmir, 35430 Turkey.
Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, Turkey.
Biomed Eng Lett. 2020 Jul 6;10(3):431-441. doi: 10.1007/s13534-020-00161-w. eCollection 2020 Aug.
Anabolic effects of low magnitude high frequency (LMHF) vibrations on bone tissue were consistently shown in the literature in vivo, however in vitro efforts to elucidate underlying mechanisms are generally limited to 2D cell culture studies. Three dimensional cell culture platforms better mimic the natural microenvironment and biological processes usually differ in 3D compared to 2D culture. In this study, we used laboratory grade filter paper as a scaffold material for studying the effects of LHMF vibrations on osteogenesis of bone marrow mesenchymal stem cells in a 3D system. LMHF vibrations were applied 15 min/day at 0.1 g acceleration and 90 Hz frequency for 21 days to residing cells under quiescent and osteogenic conditions. mRNA expression analysis was performed for alkaline phosphatase (ALP) and osteocalcin (OCN) genes, Alizarin red S staining was performed for mineral nodule formation and infrared spectroscopy was performed for determination of extracellular matrix composition. The highest osteocalcin expression, mineral nodule formation and the phosphate bands arising from the inorganic phase was observed for the cells incubated in osteogenic induction medium with vibration. Our results showed that filter paper can be used as a model scaffold system for studying the effects of mechanical loads on cells, and LMHF vibrations induced the osteogenic differentiation of stem cells.
低强度高频（LMHF）振动对骨组织的合成代谢作用在体内文献中已得到一致证实，然而，在体外阐明其潜在机制的研究通常仅限于二维细胞培养研究。三维细胞培养平台能更好地模拟自然微环境，与二维培养相比，生物过程在三维培养中通常有所不同。在本研究中，我们使用实验室级滤纸作为支架材料，在三维系统中研究LMHF振动对骨髓间充质干细胞成骨作用的影响。在静态和成骨条件下，以0.1g加速度和90Hz频率每天对驻留细胞施加15分钟的LMHF振动，持续21天。对碱性磷酸酶（ALP）和骨钙素（OCN）基因进行mRNA表达分析，对矿化结节形成进行茜素红S染色，并对细胞外基质组成进行红外光谱测定。在振动的成骨诱导培养基中培养的细胞，观察到最高的骨钙素表达、矿化结节形成以及无机相产生的磷酸盐带。我们的结果表明，滤纸可作为研究机械负荷对细胞影响的模型支架系统，并且LMHF振动诱导了干细胞的成骨分化。
