Osteoarthritis (OA) is the most prevalent joint disease affecting most of the elderly, imposing a major socio- economic burden on society. The hallmark of the disease is the breakdown of articular cartilage by elevated proteinase activities that degrade major extracellular matrix molecules, aggrecans and collagens, but currently there are no effective treatments for OA, except joint replacement surgery. Our long-term objective is to find ways to specifically inhibit these proteinases and apply them for clinical intervention in OA. The key enzymes involved are matrix metalloproteinases (MMPs) and adamalysins with thrombospondin motif (ADAMTSs). Their activities are regulated by the endogenous tissue inhibitors of metalloproteinases (TIMPs). Our recent studies have shown that TIMP-3 variants that selectively inhibit aggrecanases prevent the progression of OA in an animal model, whereas wild-type TIMP-3 that broadly inhibits MMPs and ADAMTSs was not effective. This suggests that highly selective inhibitors are essential for therapeutic development. To achieve this goal two major aims are proposed. The first is to understand the molecular basis for selectivity in our TIMP-3 variants using biochemical, biophysical and structural methods, and to use this to further develop highly discriminating inhibitors of metalloproteinases. Specifically, we will rationally design TIMP-3 variants that differentially inhibit the main two aggrecanases, ADAMTS-4 and -5, and screen human antibody phage display libraries for "exosite inhibitors" of aggrecanases and collagenases. The prototype exosite inhibitors will be further refined by mutation. The mechanism by which calcium pentosan polysulfate (CaPPS), an exosite inhibitor of aggrecanases, enhances the interactions between TIMP-3 and aggrecanases will be also elucidated. The second major aim is to evaluate the efficacy of available and newly developed metalloproteinase inhibitors using in vitro and in vivo models of OA and to validate target enzymes in human OA using these inhibitors. To this end, we will continue characterizing TIMP-3 and [-1A]TIMP-3 transgenic mice to delineate the molecular basis of their differential effects on blocking OA progression by analyzing extracellular matrix components protected by these inhibitors using a combination of immunological and proteomic approaches. Newly developed exosite inhibitors and TIMP variants will be tested for their efficacy to protect cartilage from degradation using an in vitro cartilage explant culture system and the in vivo mouse model of OA induced by medial meniscotibial ligament transaction. Effective inhibitors will be also tested in human cartilage in culture to further validate their efficacy. Using available inhibitors we will identify and characterize a novel TIMP-1- sensitive aggrecanase as it is considered as a potential therapeutic target in humans. Accomplishment of these goals will provide new principles for developing therapeutic interventions for OA.
Osteoarthritis (OA) is a disease that afflicts approximately 21 million people in the US over the age of 25, generating an enormous economic cost that is growing rapidly as the population ages. This project is aimed at developing and evaluating a novel approach for OA treatment employing engineered proteins and other molecules that specifically block the enzymes responsible for degrading cartilage in OA. We will investigate the mechanisms through which they act and assess their effectiveness using animal models of the disease and human tissues derived from joint replacement surgery.
|Seubert, Bastian; Grünwald, Barbara; Kobuch, Julia et al. (2015) Tissue inhibitor of metalloproteinases (TIMP)-1 creates a premetastatic niche in the liver through SDF-1/CXCR4-dependent neutrophil recruitment in mice. Hepatology 61:238-48|
|Troeberg, Linda; Lazenbatt, Christopher; Anower-E-Khuda, Md Ferdous et al. (2014) Sulfated glycosaminoglycans control the extracellular trafficking and the activity of the metalloprotease inhibitor TIMP-3. Chem Biol 21:1300-9|
|Lo Cascio, Leandro; Liu, Ke; Nakamura, Hiro et al. (2014) Generation of a mouse line harboring a Bi-transgene expressing luciferase and tamoxifen-activatable creER(T2) recombinase in cartilage. Genesis 52:110-9|
|Yamamoto, Kazuhiro; Owen, Kathryn; Parker, Andrew E et al. (2014) Low density lipoprotein receptor-related protein 1 (LRP1)-mediated endocytic clearance of a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4): functional differences of non-catalytic domains of ADAMTS-4 and ADAMTS-5 in LRP1 binding J Biol Chem 289:6462-74|
|Lim, N H; Meinjohanns, E; Meldal, M et al. (2014) In vivo imaging of MMP-13 activity in the murine destabilised medial meniscus surgical model of osteoarthritis. Osteoarthritis Cartilage 22:862-8|
|Scilabra, Simone D; Troeberg, Linda; Yamamoto, Kazuhiro et al. (2013) Differential regulation of extracellular tissue inhibitor of metalloproteinases-3 levels by cell membrane-bound and shed low density lipoprotein receptor-related protein 1. J Biol Chem 288:332-42|
|Stura, Enrico A; Visse, Robert; Cuniasse, Philippe et al. (2013) Crystal structure of full-length human collagenase 3 (MMP-13) with peptides in the active site defines exosites in the catalytic domain. FASEB J 27:4395-405|
|Nuti, Elisa; Santamaria, Salvatore; Casalini, Francesca et al. (2013) Arylsulfonamide inhibitors of aggrecanases as potential therapeutic agents for osteoarthritis: synthesis and biological evaluation. Eur J Med Chem 62:379-94|
|Yamamoto, Kazuhiro; Troeberg, Linda; Scilabra, Simone D et al. (2013) LRP-1-mediated endocytosis regulates extracellular activity of ADAMTS-5 in articular cartilage. FASEB J 27:511-21|
|Lo Cicero, Alessandra; Majkowska, Iwona; Nagase, Hideaki et al. (2012) Microvesicles shed by oligodendroglioma cells and rheumatoid synovial fibroblasts contain aggrecanase activity. Matrix Biol 31:229-33|
Showing the most recent 10 out of 93 publications