MechanoBiology Laboratory, Department of Orthopaedic Surgery, University of Pittsburgh, 210 Lothrop Street, BST, E1640, Pittsburgh, Pennsylvania 15213, USA.
J Orthop Res. 2010 Sep;28(9):1178-83. doi: 10.1002/jor.21123.
Exercise is known to enhance tendon size and strength, but the stem cell-based mechanisms for such exercise-induced effects are largely unknown. This study aims to explore these mechanisms by using a mouse treadmill running model to examine the effects of exercise on newly discovered tendon stem cells (TSCs). After treadmill running, patellar TSCs (PTSCs) and Achilles TSCs (ATSCs) were isolated from the mice, and their proliferation was measured in vitro. We found that treadmill running nearly doubled proliferation rates of both PTSCs and ATSCs compared to cage control mice. Moreover, using a mixed tendon cell culture consisting of TSCs and tenocytes, cellular production of collagen was found to increase by 70% and 200% in PTSCs and ATSCs, respectively, from the treadmill running group over cells from the cage control group. These findings suggest that exercise exerts its anabolic effects on tendons at least in part by increasing proliferation to expand the pool of TSCs and also by increasing TSC-related cellular production of collagen, the predominant component of tendons.
运动被认为可以增强肌腱的大小和强度，但运动引起这种效果的干细胞机制在很大程度上尚不清楚。本研究旨在通过使用小鼠跑步机跑步模型来探索这些机制，以检查运动对新发现的肌腱干细胞（TSC）的影响。在跑步机跑步后，从小鼠中分离出髌腱干细胞（PTSC）和跟腱干细胞（ATSC），并在体外测量其增殖率。我们发现，与笼养对照小鼠相比，跑步机跑步几乎使 PTSC 和 ATSC 的增殖率增加了一倍。此外，在包含 TSCs 和 tenocytes 的混合肌腱细胞培养物中，来自跑步机跑步组的 PTSC 和 ATSC 的胶原蛋白产生分别增加了 70%和 200%，而来自笼养对照组的细胞则没有增加。这些发现表明，运动对肌腱的合成作用至少部分是通过增加增殖来扩大 TSC 池，以及通过增加 TSC 相关的胶原蛋白产生来实现的，胶原蛋白是肌腱的主要成分。
