Basalo Ines M, Chahine Nadeen O, Kaplun Michael, Chen Faye H, Hung Clark T, Ateshian Gerard A
Department of Mechanical Engineering, Columbia University, 500 West 120th Street, 220 SW Mudd, MC 4703, New York, NY 10027, USA.
J Biomech. 2007;40(8):1847-54. doi: 10.1016/j.jbiomech.2006.07.007. Epub 2006 Nov 3.
The objective of this study was to investigate the effect of chondroitin sulfate (CS)-C on the frictional response of bovine articular cartilage. The main hypothesis is that CS decreases the friction coefficient of articular cartilage. Corollary hypotheses are that viscosity and osmotic pressure are not the mechanisms that mediate the reduction in the friction coefficient by CS. In Experiment 1, bovine articular cartilage samples (n=29) were tested in either phosphate buffered saline (PBS) or in PBS containing 100mg/ml of CS following 48h incubation in PBS or in PBS+100mg/ml CS (control specimens were not subjected to any incubation). In Experiment 2, samples (n=23) were tested in four different solutions: PBS, PBS+100mg/ml CS, and PBS+polyethylene glycol (PEG) (133 or 170mg/ml). In Experiment 3, samples (n=18) were tested in three solutions of CS (0, 10 and 100mg/ml). Frictional tests (cartilage-on-glass) were performed under constant stress (0.5MPa) for 3600s and the time-dependent friction coefficient was measured. Samples incubated or tested in a 100mg/ml CS solution exhibited a significantly lower equilibrium friction coefficient than the respective PBS control. PEG solutions delayed the rise in the friction coefficient relative to the PBS control, but did not reduce the equilibrium value. Testing in PBS+10mg/ml of CS did not cause any significant decrease in the friction coefficient. In conclusion, CS at a concentration of 100mg/ml significantly reduces the friction coefficient of bovine articular cartilage and this mechanism is neither mediated by viscosity nor osmolarity. These results suggest that direct injection of CS into the joint may provide beneficial tribological effects.
本研究的目的是调查硫酸软骨素（CS）-C对牛关节软骨摩擦反应的影响。主要假设是CS可降低关节软骨的摩擦系数。相应的假设是粘度和渗透压不是介导CS降低摩擦系数的机制。在实验1中，将牛关节软骨样本（n = 29）在PBS中或在含100mg/ml CS的PBS中孵育48h后进行测试（对照样本未进行任何孵育）。在实验2中，样本（n = 23）在四种不同溶液中进行测试：PBS、PBS + 100mg/ml CS以及PBS + 聚乙二醇（PEG）（133或170mg/ml）。在实验3中，样本（n = 18）在三种CS溶液（0、10和100mg/ml）中进行测试。在恒定应力（0.5MPa）下进行3600s的摩擦测试（软骨-玻璃），并测量随时间变化的摩擦系数。在100mg/ml CS溶液中孵育或测试的样本显示出比各自的PBS对照显著更低的平衡摩擦系数。相对于PBS对照，PEG溶液延迟了摩擦系数的上升，但未降低平衡值。在PBS + 10mg/ml CS中进行测试未导致摩擦系数有任何显著降低。总之，浓度为100mg/ml的CS可显著降低牛关节软骨的摩擦系数，且该机制既不是由粘度也不是由渗透压介导的。这些结果表明，将CS直接注射到关节中可能会产生有益的摩擦学效应。
