Kim Wanho, Kim Jaesang, Park Hyung-Soon, Jeon Jessie S
Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea.
KI HST, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea.
Micromachines (Basel). 2018 Dec 18;9(12):671. doi: 10.3390/mi9120671.
The skeletal muscle occupies about 40% mass of the human body and plays a significant role in the skeletal movement control. Skeletal muscle injury also occurs often and causes pain, discomfort, and functional impairment in daily living. Clinically, most studies observed the recovery phenomenon of muscle by massage or electrical stimulation, but there are limitations on quantitatively analyzing the effects on recovery. Although additional efforts have been made within in vitro biochemical research, some questions still remain for effects of the different cell microenvironment for recovery. To overcome these limitations, we have developed a microfluidic system to investigate appropriate conditions for repairing skeletal muscle injury. First, the muscle cells were cultured in the microfluidic chip and differentiated to muscle fibers. After differentiation, we treated hydrogen peroxide and 18% axial stretch to cause chemical and physical damage to the muscle fibers. Then the damaged muscle fibers were placed under the cyclic stretch condition to allow recovery. Finally, we analyzed the damage and recovery by quantifying morphological change as well as the intensity change of intracellular fluorescent signals and showed the skeletal muscle fibers recovered better in the cyclic stretched condition. In total, our in situ generation of muscle damage and induction recovery platform may be a key system for investigating muscle recovery and rehabilitation.
骨骼肌约占人体质量的40%，在骨骼运动控制中发挥着重要作用。骨骼肌损伤也经常发生，会导致日常生活中的疼痛、不适和功能障碍。临床上，大多数研究通过按摩或电刺激观察肌肉的恢复现象，但在定量分析其对恢复的影响方面存在局限性。尽管在体外生化研究方面已经做出了更多努力，但关于不同细胞微环境对恢复的影响仍存在一些问题。为了克服这些局限性，我们开发了一种微流控系统来研究修复骨骼肌损伤的合适条件。首先，将肌肉细胞培养在微流控芯片中并分化为肌纤维。分化后，我们用过氧化氢和18%的轴向拉伸对肌纤维造成化学和物理损伤。然后将受损的肌纤维置于循环拉伸条件下以促进恢复。最后，我们通过量化形态变化以及细胞内荧光信号的强度变化来分析损伤和恢复情况，并表明骨骼肌纤维在循环拉伸条件下恢复得更好。总的来说，我们原位产生肌肉损伤并诱导恢复的平台可能是研究肌肉恢复和康复的关键系统。
