力学刺激对体外保存软骨活力影响的实验研究

Effects of mechanical stimulation on viability of cartilage preserved in vitro

目的对体外保存猪膝关节软骨施加滚压力学刺激,探究力学刺激对软骨组织活力的影响。方法利用滚压力学加载装置可以为骨软骨组织提供含有组织培养液的环境,并进行仿生的力学刺激。用骨软骨取材器械体外无菌获取猪膝关节软骨,于培养液保存过程中施加力学刺激(1.5和4.0 MPa)后在第2周检测软骨的细胞存活率、蛋白多糖表达、组织形态学、杨氏模量。结果 1.5 MPa组显示最高的软骨细胞存活率、蛋白多糖含量与杨氏模量,组织形态表现良好,差异有统计学意义(P<0.05);与静态对照组相比,4.0 MPa组上述指标下降(P<0.05),形态学表现较差。结论对体外保存软骨施加适宜的滚压力学刺激,能在2周时间提高软骨细胞存活率,增强细胞外基质表达,并提升生物力学性能,为组织库软骨保存技术提供一种新方法。

Objective To investigate the effects of mechanical stimulation on chondrocyte viability, by exerting rolling-sliding mechanical stimulation on the porcine articular cartilage preserved in vitro. Methods The rolling-sliding mechanical device used could provide an environment for osteochondral tissue containing culture medium, and applied bionic mechanical stimulation. The cartilage of porcine knee was obtained in vitro under sterile condition by a special osteochondral harvester and divided into three groups. Group A was prepared as static control group, and the cartilage was preserved in the culture medium statically. Group B was 1.5 MPa group, and group C was 4.0 MPa group. In group B and C, rolling-sliding mechanical stimulation was exerted 30 min each time on cartilage at day 1 and 7, during the preservation process in the culture medium. The culture medium was refreshed every 2 days in all the three groups. Experimental tests were performed on day 14, including the survival rate of chondrocyte, the expression of proteoglycan, histomorphology, and Young’s modulus. Results The highest chondrocytes survival rate, proteoglycan content and the young’s modulus were observed in the 1.5 MPa group across all three groups, and the tissue morphology of group B was good（P 〈 0.05）. Compared with the static control group, the above index decreased in the 4.0 MPa group（P 〈 0.05）. Conclusion Exerting appropriate mechanical stimulation on cartilage can increase the survival rate of chondrocytes, enhance the expression of extracellular matrix, and improve the biomechanical properties of chondrocytes. This provides a new method for cartilage tissue bank.