Bader D L, Kempson G E, Barrett A J, Webb W
Biochim Biophys Acta. 1981 Sep 18;677(1):103-8. doi: 10.1016/0304-4165(81)90150-1.
The effects of leucocyte elastase on the tensile properties of adult human articular cartilage were examined in detail in 99 specimens from hip, knee and ankle joints in the age range 16-83 years. The results showed that elastase reduced the tensile stiffness of cartilage, both at low stress and at fracture. The tensile strength of cartilage was also considerably reduced by the action of elastase. Biochemical analysis of the incubation media, and the specimens, revealed that 90%, or more, of the proteoglycan was released from the cartilage, whilst the release of collagen was negligible. Leucocyte elastase is known to degrade the non-helical terminal peptides of cartilage collagen molecules and thereby disrupt the main intermolecular cross-links in collagen fibrils. A previous study (Kempson, G.E., Tuke, M.A., Dingle, J.T., Barrett, A.J. and Horsfield, P.H. (1976) Biochim. Biophys. Acta 428, 741-760) showed the lack of effect of proteoglycan degradation alone on the tensile strength and stiffness of cartilage. The reduction in strength and stiffness recorded in the present study can, therefore, be attributed to the action of elastase on the collagen in cartilage and it emphasises the important of covalent intermolecular cross-links to the mechanical properties of collagen fibrils.
在99个取自年龄在16至83岁之间的髋关节、膝关节和踝关节的标本中，详细研究了白细胞弹性蛋白酶对成人关节软骨拉伸特性的影响。结果表明，弹性蛋白酶在低应力和断裂时均降低了软骨的拉伸刚度。弹性蛋白酶的作用也使软骨的拉伸强度大幅降低。对孵育介质和标本的生化分析表明，90%或更多的蛋白聚糖从软骨中释放出来，而胶原蛋白的释放可以忽略不计。已知白细胞弹性蛋白酶会降解软骨胶原分子的非螺旋末端肽，从而破坏胶原纤维中的主要分子间交联。先前的一项研究（肯普森，G.E.，图克，M.A.，丁格尔，J.T.，巴雷特，A.J.和霍斯菲尔德，P.H.（1976年）《生物化学与生物物理学报》428卷，741 - 760页）表明，仅蛋白聚糖降解对软骨的拉伸强度和刚度没有影响。因此，本研究中记录的强度和刚度降低可归因于弹性蛋白酶对软骨中胶原蛋白的作用，这强调了共价分子间交联对胶原纤维力学性能的重要性。
