Inhibition of interleukin-1?-induced cartilage oligomeric matrix protein degradation in bovine articular cartilage by matrix metalloproteinase inhibitors: Potential role for matrix metalloproteinases in the generation of cartilage oligomeric matrix protein fragments in arthritic synovial fluid

Abstract

Objective. To determine whether matrix metalloproteinases (MMPs) degrade cartilage oligomeric matrix protein (COMP) to produce fragments similar to those found in synovial fluid (SF) from patients with arthritis.Methods. COMP fragments were generated in vitro by treating (a) bovine articular cartilage with interleukin-la (IL-la), (b) purified bovine COMP with MMPs, and (c) articular cartilage with MMPs. The fragments generated in each case were analyzed by Western blot, using an antibody to the C-terminal heptadecapeptide of COMP.Results. IL-la stimulation of cartilage resulted in a fragmentation of COMP, which was inhibited by MMP inhibitors CGS 27023A and BE-94. Isolated, recombinant MMPs rapidly degraded purified COMP, as well as COMP residing in cartilage. Several COMP fragments produced in vitro had similar electrophoretic mobility to those in SF of patients with arthritis.ConcZusion. MMPs may contribute to the COMP fragments found in vivo. Quantitation of MMP-specific fragments may be useful in the evaluation of MMP inhibitors in patients with arthritis.

Cartilage oligomeric matrix protein and its binding partners in the cartilage extracellular matrix: Interaction, regulation and role in chondrogenesis

“…This elaborates our information about the proteases involved in OA and their correlation with binding to COMP, and indirectly suggests that MMP-13 may in part be responsible for COMP degradation in osteoarthritis. This observation is also supported by an earlier report on cleavage of COMP by MMP-13 (Ganu et al, 1998).…”

“…Some earlier reports stated that in a bovine system, MMP-9 was capable of cleaving recombinant as well as purified COMP to generate fragments (Ganu et al, 1998). MMP-19 (found in synovium of normal and rheumatoid arthritis patients) and MMP-20 (found in tooth enamel) were observed to cleave COMP, generating a major 60 kDa fragment, indicating further interaction of COMP with metalloproteases (Stracke et al, 2000).…”

Novel Cartilage Oligomeric Matrix Protein (COMP) Neoepitopes Identified in Synovial Fluids from Patients with Joint Diseases Using Affinity Chromatography and Mass Spectrometry

“…This is consistent with the cleavage at amino acid Ser 77 observed in the present study. Purified COMP has been shown to be a substrate for several MMPs such as MMP-1 (interstitial collagenase), MMP-3 (stromelysin 1), MMP-9 (gelatinase B), and MMP-13 (collagenase 3) (34). COMP fragments containing the N-terminal domain or the EGF domain have previously been shown in synovial fluids from patients with OA, RA, and anterior cruciate ligament injury as bands of 80 and 100 kDa on Western blots (35).…”

Matrix Metalloproteinase Inhibitor CGS 27023A Protects COMP and Proteoglycan in the Bovine Articular Cartilage but not the Release of Their Fragments from Cartilage after Prolonged Stimulation in Vitro with IL‐1α

“…Rabbit anti-peptide antibody to the C-terminal domain of COMP was prepared, and bovine articular cartilage (BAC) was isolated, not in full thickness, from tarsal joints of young calves and cultured as previously described. 5 Matrix metalloproteinase inhibitors CGS 27023A (N-hydroxy-2(R)-[ [4-methoxysulfonyl](3-picolyl)amino]-3-methylbutaneamide hydrochloride and BB-94 ((2S, 3R)-5-methyl-thienylthio) methyl]hexanohydroxamic acid were synthesized in house by Drs. D. Parker and J. Skiles (Chemistry research, Novartis Institute for Biomedical Research, Summit, NJ).…”