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
Artificial joint implants are widely used to replace diseased or damaged joints. Despite the impressive success of joint replacement many artificial joints do not last indefinitely. In many patients joints last for 25 years or more but in about 15% the artificial joints will fail prematurely. Artificial joints need to be replaced because of loosening resulting from the loss of bone from around the artificial joint. The bone loss is caused by large numbers of small particles generated by excessiv ....Artificial joint implants are widely used to replace diseased or damaged joints. Despite the impressive success of joint replacement many artificial joints do not last indefinitely. In many patients joints last for 25 years or more but in about 15% the artificial joints will fail prematurely. Artificial joints need to be replaced because of loosening resulting from the loss of bone from around the artificial joint. The bone loss is caused by large numbers of small particles generated by excessive wear of the artificial joint. We now know that specialised cells in the body react to the wear particles and try to destroy them. During this process they produce molecules which lead to bone destruction. This project seeks to investigate the way particles cause bone loss and to develop drug treatments that will either prevent the loss of bone or promote new bone to replace that which has been lost. The increasing use of joint replacement and an aging population means that the number of patients with artificial joint failure will increase. This will mean that an increasing amount of medical recourses will be needed to replace failed and painful artificial joints. It is planned that the findings obtained from this project will eventually result in drug treatments which can reduce the need for the replacement of artificial joints.Read moreRead less
Regulation Of Bone Resorption And Formation In Health And Disease
Funder
National Health and Medical Research Council
Funding Amount
$5,596,183.00
Summary
Bone is continually being formed and broken down, and these two processes are critical forthe maintenance of a normal skeleton. These processes are dependent upon communication between the bone building and degrading cells, and the hormones growth factors and cytokines that are present in the circulation or produced in bone. The tightly regulated processes of bone formation and degradation need to remain equal, and are essential for the achievement and maintenance of skeletal strength and form. ....Bone is continually being formed and broken down, and these two processes are critical forthe maintenance of a normal skeleton. These processes are dependent upon communication between the bone building and degrading cells, and the hormones growth factors and cytokines that are present in the circulation or produced in bone. The tightly regulated processes of bone formation and degradation need to remain equal, and are essential for the achievement and maintenance of skeletal strength and form. Osteoporosis results from an excess of bone breakdown over formation, and our Program aims to identify the factors that regulate these processes, and develop new therapies that can modify them. We will also determine what it is about bone cell properties that make some cancers, especially those of breast and prostate, particularly prone to spread to bone.Read moreRead less
Role Of Bone-associated Macrophages In Bone Remodelling And Bone Disease
Funder
National Health and Medical Research Council
Funding Amount
$564,963.00
Summary
Musculoskeletal diseases, including osteoporosis and osteoarthritis, are a national and international health and research priorities. Over 3 million Australians suffer from arthritis and musculoskeletal conditions and their social and economic impact is expected to dramatically increase in the next 20 years as a result of the aging population. Early diagnosis, prevention and treatment of many musculoskeletal diseases are currently inadequate. Consequently, there is a high demand for effective tr ....Musculoskeletal diseases, including osteoporosis and osteoarthritis, are a national and international health and research priorities. Over 3 million Australians suffer from arthritis and musculoskeletal conditions and their social and economic impact is expected to dramatically increase in the next 20 years as a result of the aging population. Early diagnosis, prevention and treatment of many musculoskeletal diseases are currently inadequate. Consequently, there is a high demand for effective treatment options. This project grant application proposes a novel line of scientific investigation that will provide greater understanding of the contribution of macrophages (a cell type that has important roles in normal tissue maintenance and defense against infection) in bone remodelling and disease. Bone is continuously remodelled and replaced to maintain skeletal strength and mineral metabolism. We have shown that a population of macrophages is intimately associated with bone and propose that these cells play an important part in regulating bone remodelling. Macrophages have been implicated in many diseases that have damaging consequences on bone, including osteoporosis and several forms of arthritis, linking aberrant macrophage function to disease-associated bone damage. This project aims to characterize this population of bone-associated macrophages and determine their ability to influence the function of other cells integrally involved in bone remodelling. We will also undertake studies in animal models to determine whether these cells are required for bone remodelling and-or damage. Detailed description of the novel role of macrophages in bone biology will facilitate the development of superior therapeutics, preventatives and cures for bone diseases.Read moreRead less
Osteoporosis, or porous bone, is a disease characterized by low bone mass and structural deterioration of bone tissue, leading to an increased susceptibility to fractures. Understanding the nature of bone loss may lead to the discovery of a new drug target for the treatment of osteoporosis..
Analysis Of The Osteoclast Methylome For Characterisation Of Epigenetic Mechanisms Underlying Metabolic Bone Disease
Funder
National Health and Medical Research Council
Funding Amount
$299,018.00
Summary
A large number of genetic variants have been identified that have a role in osteoporosis, however for many of these, the mechanism by which they influence the disease remains to be determined. This study will fill a critical knowledge gap by investigating the epigenetic control of gene expression in osteoclasts (bone resorbing cells). This research will generate a unique international resource that will provide foundation data to understand and treat this prevalent and debilitating bone disease.
The Role Of 'Orphan' Transporters In Bone Homeostasis And Disease
Funder
National Health and Medical Research Council
Funding Amount
$675,668.00
Summary
Osteoclasts (OCs) are giant multinucleated cells exclusively responsible for physiological bone degradation (resorption). Excessive OC activity leads to localised bone destruction (osteolysis) as observed in patients with osteoarthritis and underlies decreased bone mass and fragility fractures that are a hallmark of osteoporosis. This project examines the role of an orphan solute carrier transporter in OC function and its potential involvement in bone disease.