Screening of degradative enzymes from articular cartilage in experimental osteoarthritis

Abstract

Sixteen rabbits were killed 12 weeks after sectioning of the right knee anterior cruciate ligament. The left unoperated knee served as a control. The surface area of fibrillated cartilage from femoral condyles and tibial plateau was evaluated and expressed as a percentage of articular surfaces area. Cartilage from the femoro-patellar surfaces was homogenized for the quantification of several degradative activities, based on the release of digested products. Acid phosphatase, several glycosidases and neutral protease activity from the operated joint cartilage were significantly elevated, while collagenolytic activity was unmodified. The percentage of fibrillated cartilage correlated positively with arylsulfatase, glucosidase and neutral protease but negatively with mannosidase and fucosidase. The results may be consistent with the hypothesis of a sequential degradative process leading to cartilage destruction.

Long‐distance running causes site‐dependent decrease of cartilage glycosaminoglycan content in the knee joints of beagle dogs

“…In the knee cartilage, the rate of proteoglycan loss must have exceeded the rate of synthesis after long-distance running, in the weightbearing areas of the tibial and femoral condyles. Because the superficial zone was predominantly affected, release of metalloproteinases from chondrocytes or from synovial fluid may explain the enhanced removal of proteoglycans from the tissue (35,36). Diffusion of proteoglycans from the superficial cartilage matrix would occur more easily than diffusion from deeper zones.…”

Biological aspects of early osteoarthritis

“…There are no spontaneous models of OA [144]. In the ACLT model (Table 1), increased cartilage thickness is a first sign, preceding the appearance of early OA changes such as fibrillations, fissures and erosions of cartilage, which appear as early as 4 weeks postinduction [192, 193]. Full‐depth erosions of articular cartilage occur already after 8 weeks in 40% of the femoral condyles [38].…”

Therapeutic effects of the stromal vascular fraction and adipose-derived stem cells on osteoarthritis in an experimental rabbit model

“…This study was approved by our institutional animal management and use committee. OA was surgically induced by anterior cruciate ligament (ACL) transection (ACLT) following the procedures described in previous studies [31,32]. In the ACLT procedure, a 2 cm skin incision was made, and the ACL was exposed using the medial parapatellar approach.…”