ARTORG Center for Biomedical Engineering, Spine Research Center, Institute for Surgical Technology and Biomechanics, University of Bern, Stauffacherstrasse 78, 3014 Bern, Switzerland.
Eur Spine J. 2011 Nov;20(11):1796-812. doi: 10.1007/s00586-011-1827-1. Epub 2011 May 4.
Loading is important to maintain the balance of matrix turnover in the intervertebral disc (IVD). Daily cyclic diurnal assists in the transport of large soluble factors across the IVD and its surrounding circulation and applies direct and indirect stimulus to disc cells. Acute mechanical injury and accumulated overloading, however, could induce disc degeneration. Recently, there is more information available on how cyclic loading, especially axial compression and hydrostatic pressure, affects IVD cell biology. This review summarises recent studies on the response of the IVD and stem cells to applied cyclic compression and hydrostatic pressure. These studies investigate the possible role of loading in the initiation and progression of disc degeneration as well as quantifying a physiological loading condition for the study of disc degeneration biological therapy. Subsequently, a possible physiological/beneficial loading range is proposed. This physiological/beneficial loading could provide insight into how to design loading regimes in specific system for the testing of various biological therapies such as cell therapy, chemical therapy or tissue engineering constructs to achieve a better final outcome. In addition, the parameter space of 'physiological' loading may also be an important factor for the differentiation of stem cells towards most ideally 'discogenic' cells for tissue engineering purpose.
负荷对于维持椎间盘（IVD）基质转换的平衡很重要。日常的周期性昼夜节律有助于大的可溶性因子在 IVD 及其周围循环中的运输，并对椎间盘细胞施加直接和间接的刺激。然而，急性机械损伤和累积性过载会导致椎间盘退变。最近，关于周期性负荷（尤其是轴向压缩和静水压力）如何影响 IVD 细胞生物学的信息越来越多。这篇综述总结了最近关于 IVD 和干细胞对施加的循环压缩和静水压力的反应的研究。这些研究探讨了负荷在椎间盘退变的起始和进展中的可能作用，并量化了椎间盘退变生物治疗研究的生理负荷条件。随后，提出了一个可能的生理/有益的负荷范围。这种生理/有益的负荷可以深入了解如何为各种生物治疗（如细胞治疗、化学治疗或组织工程构建体）设计特定系统中的负荷方案，以实现更好的最终结果。此外，“生理”负荷的参数空间对于干细胞向最理想的“椎间盘形成”细胞的分化也可能是一个重要因素，以实现组织工程的目的。
