Molecular Mechanisms Of Cartilage Degeneration In Osteoarthritis
Funder
National Health and Medical Research Council
Funding Amount
$457,517.00
Summary
Arthritis affects 15% of the entire Australian population and 50% in people over 60. The most common form of joint disease by far is osteoarthritis (OA). One of the central features of OA is the breakdown of the cartilage that covers the ends of bones in joints, and this is a major determinant of the long term outcome and need for joint replacement surgery. There are no current therapies that halt or reverse cartilage breakdown in OA. This is largely due to our incomplete understanding of the mo ....Arthritis affects 15% of the entire Australian population and 50% in people over 60. The most common form of joint disease by far is osteoarthritis (OA). One of the central features of OA is the breakdown of the cartilage that covers the ends of bones in joints, and this is a major determinant of the long term outcome and need for joint replacement surgery. There are no current therapies that halt or reverse cartilage breakdown in OA. This is largely due to our incomplete understanding of the molecular changes and pathways involved in both the onset and progression of cartilage breakdown. Powerful new genomic approaches allow simultaneous screening of changes in a broad profile of genes, particulalrly in humans and mice following complete sequencing of their genomes. By applying this new technology in the earliest stages of cartilage degeneration in OA, the role of novel genes and the pathways involved in the onset of this disease process can be discovered. However, to investigate changes at the initiation of disease, tissue from animal rather than human joints must be used due to the difficulty in obtaining pre-symptomatic human cartilage. In order to maximise the number of genes screened, cartilage from a novel surgically induced model of OA in mice will be used in this study. We have developed micro dissection and linear mRNA amplification methods to overcome inherent problems with tissue availability from this small animal species. Successful completion of these studies will for the first time allow identification of the complex changes that occur in early OA. An important and likely outcome of this research will be identification of novel matrix proteins and regulatory molecules that will provide critical information for the development of new diagnostic and therapeutic approaches to OA.Read moreRead less
Investigation And Modulation Of RANKL-induced Osteoclastogensis, Bone Resorption And Signaling Pathways
Funder
National Health and Medical Research Council
Funding Amount
$33,825.00
Summary
Osteoclasts are exclusively responsible for the degradation of bone matrix. RANKL is a member of a ligand-receptor system which directly regulates osteoclast differentiation and bone resorption. New treatment regime for various bone diseases have been highly sought after for many years. The identification of potential natural compounds that inhibit the formation and function of osteoclasts might serve as a useful tool for such treatment.
NT-3 As An Upstream And Potentially Master Regulator Promoting Bone Fracture Healing
Funder
National Health and Medical Research Council
Funding Amount
$712,857.00
Summary
There is a strong clinical need for cost-effective treatments for delayed healing or non-union bone fractures. Our recent data suggest injury site-derived neurotrophin-3 (NT-3) may be an important overall regulator of bone repair by inducing key factors involved in fracture callus formation and remodelling. This project will address roles and mechanisms of endogenous NT-3 in bone repair and the likelihood of exogenous NT-3 protein in promoting bone healing in clinically relevant fracture models.
Heat Shock Transcription Factors In Bone Remodeling And Disease
Funder
National Health and Medical Research Council
Funding Amount
$480,427.00
Summary
The denisity of bone is finely balaned and required for a healthy lifestyle. During times of disease, damage or drug treatments the bone can be compromised, often decreasing in density and becoming fragile. This often leads to fractures, pain and a poor quality of life. This proposal seeks to investigate whether stress insults to bones plays a role in the loss of bone. This will provide new insights into bone loss during disease and lead to novel treatment strategies.
The Role Of TNF Family Members TWEAK And TNF-alpha In Bone Remodelling
Funder
National Health and Medical Research Council
Funding Amount
$566,946.00
Summary
Bone remodelling, or turnover, is the process by which bone is broken down by osteoclasts and replaced by osteoblasts. Disruption of this process is the cause of many bone-related diseases that affect millions of Australians and countless others worldwide. It is controlled by the complex interactions of a large number of systemic factors (hormones) and locally acting agents, such as chemokines and cytokines, the details of which are not fully understood. Each of these factors, however, is a pote ....Bone remodelling, or turnover, is the process by which bone is broken down by osteoclasts and replaced by osteoblasts. Disruption of this process is the cause of many bone-related diseases that affect millions of Australians and countless others worldwide. It is controlled by the complex interactions of a large number of systemic factors (hormones) and locally acting agents, such as chemokines and cytokines, the details of which are not fully understood. Each of these factors, however, is a potential therapeutic target. Pro-inflammatory cytokines, those that are associated with inflammatory diseases such as Rheumatoid Arthritis (RA), are known to have key roles in both the physiology and pathology of bone. TWEAK is a recently described member of the TNF family of cytokines. We have shown that TWEAK is a novel mediator of inflammatory arthritis in mouse model systems and is therefore a likely candidate as a therapeutic target. We now have extensive preliminary data to suggest that TWEAK is involved in human RA, and also in the regulation of normal bone remodelling. TWEAK therefore may be implicated in a wide spread of bone diseases, including osteoporosis. We believe it is of great importance to perform a thorough analysis of TWEAK in bone biology, and we propose to do so.Read moreRead less
Structural And Functional Analyses Of Rat Receptor Activator Of NF-kb Ligand
Funder
National Health and Medical Research Council
Funding Amount
$226,320.00
Summary
Rat RANKL (Xu and Zheng, rat RANKL, AustraliaProvisional Patent PQ3147) has a variety of biological activities including osteoclast differentiation and polarization, and dendritic cell function. Overproduction or increased activity of RANKL can result in excessive osteoclast formation, activation, and bone resorption. This process contributes to many common bone lytic disorders such as osteoporosis, Paget's disease, bone metastatic diseases, arthritis, aseptic bone loosening and non-union of fra ....Rat RANKL (Xu and Zheng, rat RANKL, AustraliaProvisional Patent PQ3147) has a variety of biological activities including osteoclast differentiation and polarization, and dendritic cell function. Overproduction or increased activity of RANKL can result in excessive osteoclast formation, activation, and bone resorption. This process contributes to many common bone lytic disorders such as osteoporosis, Paget's disease, bone metastatic diseases, arthritis, aseptic bone loosening and non-union of fractures. This proposal addresses the important and fundamental issue of RANKL regarding the role of molecular structure on its biological function. We have established that the TNF-like core domain is the functional domain, important for osteoclastogenesis, osteoclast polarisation and protecting against Fas-triggered apoptosis. This proposal will further characterise the mutant forms of the TNF-like core domain of RANKL using site directed mutagenesis and protein truncation analysis, and assess their respective binding activities to OPG and RANK, and their biological activities both in vitro and in vivo. It will lead us into better understanding of the structure-function relationship of RANKL. Ideally, we would like to develop a relative agent for the suppression of osteolysis in orthopaedic related diseases including osteoporosis. Such an optimized molecule could become a potent therapeutic agent that selectively inhibits osteoclast formation and bone resorption.Read moreRead less