Figure 3 A–F.

Effects of mechanical loading on Achilles tendon composition. (A–C): The Achilles tendon (A) is composed of an extracellular matrix (B) containing cells known as tenocytes. (C) TGF-β signaling leads to downstream activation of the smad proteins, leading to expression of scleraxis (Scx) and collagens. (D–F): To elucidate the effects of fluid shear stresses on the downstream expression of Scx, a microfluidics device was used to provide a dose dependent response of fluid shear stresses (D, regions I–IV). (E,F) Moderate shear stresses promote increased expression of Scx, whereas removal of shear stress resulted in no expression of Scx. Collectively, these studies suggest that mechanical loading and its downstream mediators directly affect tendon and may be partially mediated by TGF-β signaling.

Panels A–C: Image reproduced with permission from Sharir et al. (2011)62. Panels D–F: Image reproduced with permission from Maeda et al. (2011)19.