The overall objective of the proposed research is to characterize the role of tissue specific cathepsins in extracellular matrix (ECM) protein degradation in cartilage. Previously, we and others identified cathepsins K and S as the predominant cysteine proteases in osteoclasts and macrophages, respectively, and characterized the extremely potent ECM- degrading activities of both cathepsins. We demonstrated that cathepsin K also is expressed in rheumatoid arthritis (RA) synovial fibroblasts and in mono- as well multi-nucleated cells of subchondral bone. Our working hypothesis is that cathepsins K and S are directly involved in cartilage degradation in arthritic joints. Therefore, in vitro and in vivo experiments will be undertaken to further characterize the biological functions of these cathepsins and to determine if these cathepsins cause excessive ECM degradation in tissue-degenerative pathologies such as RA. The expression of human cathepsins K and S will be localized in RA and non-RA joints and synovial fluid and correlated with the focal sites of cartilage erosion. Primary synovial fibroblast cultures from RA and non- RA specimens will be characterized with respect to the expression and secretion of both cathepsin activities. Substrate specificity studies will be undertaken with purified human cartilage proteins as well as with intact cartilage using recombinant cathepsins K and S. identified cleavage sites in ECM substrates will be used to produce specific neoepitope antibodies to identify cathepsin-released cleavage products in normal and diseased cartilage and synovial fluid. The extracellular processing of the cathepsin precursors will be assessed using known ECM-resident proteases. Furthermore, cooperative effects of cathepsin and MMP activities towards cartilage proteins will be determined. Ex-vivo cell models of cartilage erosion and antigen-induced arthritis mouse models using cathepsin K- deficient animals will be exploited to characterize the contribution of cathepsins K and S to the cartilage degeneration under non-inflammatory and inflammatory conditions. Altogether, these studies should determine the role of cathepsins K and S in ECM-protein degradation, and investigate novel strategies for the treatment of RA and other disorders with excessive ECM-degradation.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Research Project (R01)
Project #
5R01AR046182-02
Application #
6375232
Study Section
Pathobiochemistry Study Section (PBC)
Program Officer
Tyree, Bernadette
Project Start
2000-05-15
Project End
2005-04-30
Budget Start
2001-05-01
Budget End
2002-04-30
Support Year
2
Fiscal Year
2001
Total Cost
$310,744
Indirect Cost
Name
Mount Sinai School of Medicine
Department
Genetics
Type
Schools of Medicine
DUNS #
114400633
City
New York
State
NY
Country
United States
Zip Code
10029
Jordans, Silvia; Jenko-Kokalj, Sasa; Kuhl, Nicole M et al. (2009) Monitoring compartment-specific substrate cleavage by cathepsins B, K, L, and S at physiological pH and redox conditions. BMC Biochem 10:23
Reis, Flavia C G; Costa, Tatiana F R; Sulea, Traian et al. (2007) The propeptide of cruzipain--a potent selective inhibitor of the trypanosomal enzymes cruzipain and brucipain, and of the human enzyme cathepsin F. FEBS J 274:1224-34
Askew, David J; Cataltepe, Sule; Kumar, Vasantha et al. (2007) SERPINB11 is a new noninhibitory intracellular serpin. Common single nucleotide polymorphisms in the scaffold impair conformational change. J Biol Chem 282:24948-60
Weidauer, Enrico; Yasuda, Yoshiyuki; Biswal, Bichitra K et al. (2007) Effects of disease-modifying anti-rheumatic drugs (DMARDs) on the activities of rheumatoid arthritis-associated cathepsins K and S. Biol Chem 388:331-6
Choe, Youngchool; Leonetti, Francesco; Greenbaum, Doron C et al. (2006) Substrate profiling of cysteine proteases using a combinatorial peptide library identifies functionally unique specificities. J Biol Chem 281:12824-32
Linke, Martin; Gordon, Ronald E; Brillard, Michele et al. (2006) Degradation of apolipoprotein B-100 by lysosomal cysteine cathepsins. Biol Chem 387:1295-303
Everts, Vincent; Korper, Wolf; Hoeben, Kees A et al. (2006) Osteoclastic bone degradation and the role of different cysteine proteinases and matrix metalloproteinases: differences between calvaria and long bone. J Bone Miner Res 21:1399-408
Yasuda, Yoshiyuki; Kaleta, Jadwiga; Bromme, Dieter (2005) The role of cathepsins in osteoporosis and arthritis: rationale for the design of new therapeutics. Adv Drug Deliv Rev 57:973-93
Oorni, Katariina; Sneck, Mia; Bromme, Dieter et al. (2004) Cysteine protease cathepsin F is expressed in human atherosclerotic lesions, is secreted by cultured macrophages, and modifies low density lipoprotein particles in vitro. J Biol Chem 279:34776-84
Wang, D; Li, W; Pechar, M et al. (2004) Cathepsin K inhibitor-polymer conjugates: potential drugs for the treatment of osteoporosis and rheumatoid arthritis. Int J Pharm 277:73-9

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