Department of Orthopaedic Surgery, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA.
Tissue Eng Part A. 2012 Jun;18(11-12):1101-8. doi: 10.1089/ten.TEA.2011.0285. Epub 2012 Mar 7.
Stem cell therapy for tissue repair is a rapidly evolving field and the factors that dictate the physiological responsiveness of stem cells remain under intense investigation. In this study we hypothesized that the mechanical loading history of muscle-derived stem cells (MDSCs) would significantly impact MDSC survival, host tissue angiogenesis, and myocardial function after MDSC transplantation into acutely infarcted myocardium. Mice with acute myocardial infarction by permanent left coronary artery ligation were injected with either nonstimulated (NS) or mechanically stimulated (MS) MDSCs. Mechanical stimulation consisted of stretching the cells with equibiaxial stretch with a magnitude of 10% and frequency of 0.5 Hz. MS cell-transplanted hearts showed improved cardiac contractility, increased numbers of host CD31+ cells, and decreased fibrosis, in the peri-infarct region, compared to the hearts treated with NS MDSCs. MS MDSCs displayed higher vascular endothelial growth factor expression than NS cells in vitro. These findings highlight an important role for cyclic mechanical loading preconditioning of donor MDSCs in optimizing MDSC transplantation for myocardial repair.
干细胞疗法在组织修复中是一个快速发展的领域，决定干细胞生理反应的因素仍在深入研究中。在这项研究中，我们假设肌肉来源干细胞（MDSCs）的机械加载历史将显著影响 MDSC 在急性心肌梗死后移植到心肌中的存活、宿主组织血管生成和心肌功能。通过永久性左冠状动脉结扎使小鼠发生急性心肌梗死，然后向其注射未经刺激（NS）或机械刺激（MS）的 MDSCs。机械刺激包括对细胞进行等双轴拉伸，拉伸幅度为 10%，频率为 0.5 Hz。与用 NS MDSCs 治疗的心脏相比，MS 细胞移植的心脏显示出更好的心脏收缩力、更多的宿主 CD31+细胞和减少的梗塞周围区域纤维化。MS MDSCs 在体外表现出比 NS 细胞更高的血管内皮生长因子表达。这些发现强调了对供体 MDSCs 进行循环机械加载预处理在优化 MDSC 移植用于心肌修复中的重要作用。
