The Role Of TWIST Family Basic Helix-Loop-Helix Transcription Factors In Bone Cell Commitment, Function And Repair
Funder
National Health and Medical Research Council
Funding Amount
$485,928.00
Summary
In developed countries, projected estimates predict an alarming trend of a two to three fold increase in the number of fractures that require surgical intervention and rehabilitation therapy in the coming decades as a consequence of an aging population. Fracture healing is a complex physiological process that involves the coordinated participation of different bone marrow cells, immune cells and skeletal progenitor cells. Multiple factors regulate interactions between these cell types that influ ....In developed countries, projected estimates predict an alarming trend of a two to three fold increase in the number of fractures that require surgical intervention and rehabilitation therapy in the coming decades as a consequence of an aging population. Fracture healing is a complex physiological process that involves the coordinated participation of different bone marrow cells, immune cells and skeletal progenitor cells. Multiple factors regulate interactions between these cell types that influence the capacity of bone cell progenitors to develop into functional bone forming cells known as osteoblasts. An understanding of the fracture healing is critical for the future advancement of fracture treatment, and for identifying the mechanisms of skeletal growth and repair as well as the causes of aging and disease. This proposal seeks to identify critical regulatory molecules that act to mediate bone cell progenitor recruitment and development during bone fracture repair.Read moreRead less
Cell Biology Of Stress Fractures: Activation Of Remodelling At Sites Of Non-union
Funder
National Health and Medical Research Council
Funding Amount
$493,817.00
Summary
Stress fractures are debilitating injuries. We characterised a model of stress fractures in rat ulnae, learning that they heal by activated remodelling, that key genes are expressed in a temporal pattern, and that part of the fracture remains un-healed, similar to many clinical cases. Now, we will examine cell localisation of important genes necessary for remodelling, and test the efficacy of different growth factors to activate a healing response in the non-healed section of the fracture.
Inhibition Of Bone Resorption Increases Skeletal Mechanical Strength By Thickening Trabecular Structures
Funder
National Health and Medical Research Council
Funding Amount
$175,648.00
Summary
This project will identify the basis by which a number of therapies for osteoporosis decrease the risk of bone fractures. Currently at least four classes of these compounds in current use for the treatment of osteoporosis. Some of them have been found to have a very marked beneficial effect by halving the risk of fracture. This study will determine if each of these classes of compounds have the ability to increase the mechanical strength of bone to the same level and if each of these compounds h ....This project will identify the basis by which a number of therapies for osteoporosis decrease the risk of bone fractures. Currently at least four classes of these compounds in current use for the treatment of osteoporosis. Some of them have been found to have a very marked beneficial effect by halving the risk of fracture. This study will determine if each of these classes of compounds have the ability to increase the mechanical strength of bone to the same level and if each of these compounds has the same effects on bone structure. Further the effects of stimulating bone formation by subjecting the skeletal to mechanical stress, on the efficacy of each of the therapies will be established. Conversely the effect of aging, which imposes a limitation on bone formation, will be studied.Read moreRead less
Modelling The Loss Of NF1 Heterozygosity In Congenital Pseudarthrosis Of The Tibia (CPT).
Funder
National Health and Medical Research Council
Funding Amount
$482,978.00
Summary
Congenital pseudarthrosis of the tibia or CPT is a dibilitating orthopaedic condition that affects children. Healing of a CPT is poor and, even with modern surgical techniques, amputation is a frequent outcome. As a group experienced in animal models of bone healing, we are well positioned to develop advanced genetic models of CPT in mice. With a better understanding of the underlying processes in CPT we will be able to develop treatments for this severe childhood condition.
Molecular And Histopathological Investigation Of Stress Fracture Healing And Effects Of Anti-inflammatory Drugs.
Funder
National Health and Medical Research Council
Funding Amount
$412,652.00
Summary
Stress fractures are debilitating injuries affecting children, adolescents and adults in sport, and army recruits. They also occur in horse and greyhound racing, often resulting in euthanasia of the animals involved. They incur considerable costs in medical expenses, time lost from sport and interruption to military training. But, there is almost no information on the mechanism of healing of these fractures. Non-steroidal anti-inflammatory drugs (NSAIDs) are still the most widely used medication ....Stress fractures are debilitating injuries affecting children, adolescents and adults in sport, and army recruits. They also occur in horse and greyhound racing, often resulting in euthanasia of the animals involved. They incur considerable costs in medical expenses, time lost from sport and interruption to military training. But, there is almost no information on the mechanism of healing of these fractures. Non-steroidal anti-inflammatory drugs (NSAIDs) are still the most widely used medication in management of musculoskeletal injuries, yet their effect on healing of stress fractures is unknown. NSAIDs delay fracture healing, but until recently there has been no standardised way of studying stress fractures. We have created, for the first time, a well-characterised, non-invasive model of stress fractures in the forearm of rats that closely resembles the clinical situation. This provides a novel and unique opportunity to determine the histological and molecular mechanism of stress fracture healing, and to investigate effects of antiinflammatory-analgesic medications on this process. Rats will have an experimental stress fracture produced in one forelimb, and its healing will be examined up to ten weeks using microscopic investigation and analysis of the genes that are turned off or on to initiate the process. Groups of rats will also be treated with antiinflammatory drugs such as ibuprofen, specific COX-2 inhibitors and a new class of drugs that target early immune responses called C5a receptor antagonists. The analgesic Paracetamol will also be investigated as an alternative to the NSAIDs described above. There is widespread use of anti-inflammatory agents in managing stress fractures, so it is vital that their effects on stress fracture healing be examined. This project has enormous significance for optimising approaches for clinical management of stress fractures and for understanding the interaction of anti-inflammatory or analgesic agents in that process.Read moreRead less
Furin: Carving-up Vital Substrates For Bone Remodelling And Homeostasis
Funder
National Health and Medical Research Council
Funding Amount
$815,972.00
Summary
Osteoporosis, or porous bone, is a disease characterized by low bone mass and structural deterioration of bone tissue, leading to bone fragility and an increased susceptibility to fractures. It is caused by an imbalance between the cells that are constantly reabsorbing and reforming bone. The proposed project will address furin as a novel regulator of bone remodelling.
Delayed bone healing can be a considerable problem in both children and adults. Up to 10% of fractures fail to heal properly. An advanced understanding of the cellular responses in bone repair and their manipulation could improve the lives of many patients with orthopaedic problems. These studies will advance out knowledge of interventions to promote bone healing which could be translated rapidly into clinical care.
Relationships Between Human Osteoblasts And Haemopoietic Cells In Bone Remodelling
Funder
National Health and Medical Research Council
Funding Amount
$436,450.00
Summary
Bone diseases, such as osteoporosis and osteoarthritis, currently afflict more than 4 million Australians. These diseases are characterised by abnormal bone remodelling, which can result in a net loss of bone (for example, in osteoporosis) or abnormal bone structure (for example, in osteoarthritis). We are seeking to better understand the factors that regulate bone remodelling, and particularly the cells involved in this process. Physiological bone remodelling results from the intimate collabora ....Bone diseases, such as osteoporosis and osteoarthritis, currently afflict more than 4 million Australians. These diseases are characterised by abnormal bone remodelling, which can result in a net loss of bone (for example, in osteoporosis) or abnormal bone structure (for example, in osteoarthritis). We are seeking to better understand the factors that regulate bone remodelling, and particularly the cells involved in this process. Physiological bone remodelling results from the intimate collaboration between osteoblasts and osteoclasts. Osteoblasts stimulate the formation of osteoclasts and also produce new bone at resporption sites. However, the way that the same type of cell can perform both these tasks, is not clear. Our studies are designed to increase our understanding of the development of human osteoblasts and of the factors that cause them to be sequentially pro-osteoclastic and then pro-osteogenic. We believe that an important factor in this process is vitamin D and we will test the hypothesis that this molecule is produced in bone and acts locally to regulate bone turnover.Read moreRead less