Changes in expression of proteinases and tissue inhibitors of metalloproteinases in advance of osteoarthritis

软骨基质的渐进性丢失是骨关节炎(OA)的病理特征。以往的研究表明，几种蛋白水解酶的表达在软骨破坏中起着关键作用。在这项研究中，我们特别关注软骨组织中的区域差异，研究了正常、早期和晚期膝骨性关节炎关节软骨中关键蛋白(MMP-13、ADAMTS-5)及其组织抑制物(TIMPs)的表达。这项研究的结果可能有助于揭示骨性关节炎病理学的一个新方面。

Gradual loss of cartilage matrix is a hallmark of pathology of osteoarthritis (OA). Previous studies have shown that the expression of several proteinases play a pivotal role in cartilage breakdown. In this study, we investigated the expression of key proteinases (MMP-13, ADAMTS-5) together with that of tissue inhibitors of metalloproteinases (TIMPs) within cartilage from normal, early, or advanced OA knee joints, paying special attention to the regional difference within cartilage tissue.The result of this study has shown that the expression of TIMP-2, 3 and 4 reduced in cartilage where early OA changes occur, before the elevation of MMP-13 and ADAMTS-5 expression. The result of this study might shed light on a novel aspect of OA pathology.