Trinity Centre for Bioengineering, Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin 2, Ireland.
Biomech Model Mechanobiol. 2010 Jun;9(3):359-72. doi: 10.1007/s10237-009-0182-1. Epub 2009 Dec 29.
A number of mechano-regulation theories have been proposed that relate the differentiation pathway of mesenchymal stem cells (MSCs) to their local biomechanical environment. During spontaneous repair processes in skeletal tissues, the organisation of the extracellular matrix is a key determinant of its mechanical fitness. In this paper, we extend the mechano-regulation theory proposed by Prendergast et al. (J Biomech 30(6):539-548, 1997) to include the role of the mechanical environment on the collagen architecture in regenerating soft tissues. A large strain anisotropic poroelastic material model is used in a simulation of tissue differentiation in a fracture subject to cyclic bending (Cullinane et al. in J Orthop Res 20(3):579-586, 2002). The model predicts non-union with cartilage and fibrous tissue formation in the defect. Predicted collagen fibre angles, as determined by the principal decomposition of strain- and stress-type tensors, are similar to the architecture seen in native articular cartilage and neoarthroses induced by bending of mid-femoral defects in rats. Both stress and strain-based remodelling stimuli successfully predicted the general patterns of collagen fibre organisation observed in vivo. This provides further evidence that collagen organisation during tissue differentiation is determined by the mechanical environment. It is envisioned that such predictive models can play a key role in optimising MSC-based skeletal repair therapies where recapitulation of the normal tissue architecture is critical to successful repair.
许多机械调节理论已经被提出，这些理论将间充质干细胞（MSCs）的分化途径与它们的局部生物力学环境联系起来。在骨骼组织的自发修复过程中，细胞外基质的组织是其机械适应性的关键决定因素。在本文中，我们扩展了 Prendergast 等人提出的机械调节理论（J Biomech 30(6):539-548, 1997），将机械环境对再生软组织中胶原结构的作用包括在内。在一个受循环弯曲（Cullinane 等人在 J Orthop Res 20(3):579-586, 2002）作用的骨折部位的组织分化模拟中，使用了大应变各向异性多孔弹性材料模型。该模型预测在缺陷处会发生非愈合，形成软骨和纤维组织。由应变和应力张量的主分解确定的预测胶原纤维角度与在天然关节软骨和通过弯曲大鼠股骨中段缺陷诱导的新关节中观察到的结构相似。基于应力和应变的重塑刺激都成功地预测了体内观察到的胶原纤维组织的一般模式。这进一步证明了在组织分化过程中胶原组织是由机械环境决定的。可以预见，这种预测模型可以在基于 MSC 的骨骼修复治疗中发挥关键作用，在这种治疗中，正常组织结构的再现对于成功修复至关重要。
