Furusawa Kazuya, Kawahana Yuuki, Miyashita Ryoya
Department of Applied Chemistry and Food Science, Faculty of Environmental and Information Science, Fukui University of Technology, Fukui 910-8505, Japan.
Gels. 2023 Feb 8;9(2):141. doi: 10.3390/gels9020141.
Tissue engineering methods that aim to mimic the hierarchical structure of skeletal muscle tissue have been widely developed due to utilities in various fields of biology, including regenerative medicine, food technology, and soft robotics. Most methods have aimed to reproduce the microscopical morphology of skeletal muscles, such as the orientation of myotubes and the sarcomere structure, and there is still a need to develop a method to reproduce the macroscopical morphology. Therefore, in this study, we aim to establish a method to reproduce the macroscopic morphology of skeletal muscle by constructing an engineered muscle tissue (EMT) by culturing embryonic chicken myoblast-like cells that are unidirectionally aligned in collagen hydrogels with micro-channels (i.e., MCCG). Whole mount fluorescent imaging of the EMT showed that the myotubes were unidirectionally aligned and that they were bundled in the collagen gel matrix. The myotubes contracted in response to periodic electrostimulations with a frequency range of 0.5-2.0 Hz, but not at 5.0 Hz. Compression tests of the EMT showed that the EMT had anisotropic elasticity. In addition, by measuring the relaxation moduli of the EMTs, an anisotropy of relaxation strengths was observed. The observed anisotropies could be attributed to differences in maturation and connectivity of myotubes in the directions perpendicular and parallel to the long axis of the micro-channels of the MCCG.
由于在包括再生医学、食品技术和软机器人技术在内的生物学各个领域的实用性，旨在模拟骨骼肌组织层次结构的组织工程方法已得到广泛发展。大多数方法旨在重现骨骼肌的微观形态，如肌管的方向和肌节结构，仍然需要开发一种重现宏观形态的方法。因此，在本研究中，我们旨在通过在具有微通道的胶原水凝胶（即MCCG）中培养单向排列的胚胎鸡成肌样细胞来构建工程肌肉组织（EMT），从而建立一种重现骨骼肌宏观形态的方法。EMT的整体荧光成像显示，肌管单向排列并在胶原凝胶基质中束状排列。肌管在0.5 - 2.0 Hz频率范围内的周期性电刺激下收缩，但在5.0 Hz时不收缩。EMT的压缩测试表明，EMT具有各向异性弹性。此外，通过测量EMT的松弛模量，观察到松弛强度的各向异性。观察到的各向异性可能归因于MCCG微通道长轴垂直和平行方向上肌管成熟度和连接性的差异。
