A PROPOSAL FOR CONTINUATION OF A RESEARCH PROGRAM TO INVESTIGATE THE ROLE OF CATHEPSIN K IN OSTEOARTHRITIS (OA) AND CREATE NEW DIAGNOSTIC ASSAYS FOR THE EARLY DETECTION OF OSTEOARTHRITIS
Osteoarthritis is a chronic painful disease of joints that involves the progressive destruction of the articular cartilage and bone and leads to pain. It affects both humans and animals. Animals can serve as models for the human disease and in this case we will study equine OA. There is currently no effective medication that can effectively reverse the cartilage destruction in OA. This is mediated by enzymes. It was believed to be due to MMP enzymes alone until recently we showed that Cathepsin K is also involved. It is currently believed that we should try to identify cartilage degeneration early to attempt to preserve the structure. At this early stage the degeneration is not visible on X rays or MRI. However, when the enzymes break up the cartilage matrix ( collagen in particular), they release signature fragments that can be detected in the body fluids. Our goal is to be able to develop a body fluid test that will allow us to detect the specific breakdown of the articular cartilage in a patient by the enzyme Cathespin K. This would be in the very early molecular phases of the disease.