Intrinsic Bone Qualities In Fragility Fracture Patients: Mass, Microarchitecture, Mineralization And Damage Accumulation
Funder
National Health and Medical Research Council
Funding Amount
$447,027.00
Summary
Osteoporosis drug therapies have been associated with a significant reduction in fragility fracture. Patients receiving osteoporosis drugs, which have different effects on BMD, may have similar reductions in fractures. Furthermore, patients with fragility fractures may have abnormalities in bone structural and material properties. Changes to the process of bone renewal, due to drug therapy, may explain why fracture risk decreases where no detectable change to the structure of bone has been detec ....Osteoporosis drug therapies have been associated with a significant reduction in fragility fracture. Patients receiving osteoporosis drugs, which have different effects on BMD, may have similar reductions in fractures. Furthermore, patients with fragility fractures may have abnormalities in bone structural and material properties. Changes to the process of bone renewal, due to drug therapy, may explain why fracture risk decreases where no detectable change to the structure of bone has been detected. It has also been shown that when bone renewal is suppressed microdamage accumulates in bone tissue, leading to reduced bone toughness. The toughness of bone is of primary importance in relation to fragility fractures, and it has been shown that the fatigue strength and fracture toughness (work to fracture) reduce considerably with age. This proposed study would seek to elucidate the role of bone tissue-level properties in determining bone quality for human subjects: patients with fragility hip fractures on no osteoporosis drugs therapy, hip fracture patients on osteoporosis drugs therapies, and normal age- and sex-matched individuals. Our laboratory has extensive experience in the analysis of the structure of human bone tissue. Recently, we have developed novel and unique techniques to assess bone quality, using micro-CT, backscatter SEM imaging, confocal microscopy and immunohistochemistry. This multifaceted study will identify at the bone tissue-level the structural mechanisms (micro-architecture, mineralisation, and microscopic cracking) that are indicative of the efficacy of fragility fracture drugs. Better understanding of the mechanisms by which bones are less likely to fracture will enable better targeting of osteoporosis drug therapy to individuals at risk of fragility fracture.Read moreRead less
Vertebral Body Strength: Contribution Of Bone Mass, Bone Structure And Material Properties
Funder
National Health and Medical Research Council
Funding Amount
$434,498.00
Summary
This study will determine the contributions to vertebral body strength made by its structural and material properties. Using state-of-the-art computed-tomography scanners, digitised representations of vertebral bodies in three-dimensions will be produced, which enable measurement of bone structure. After strength testing of the vertebral bodies, the structural and material properties, which combine to predict vertebral body strength, will be identified in an aged population.
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
Bone Fragility: The Neglected Role Of Cortical Porosity
Funder
National Health and Medical Research Council
Funding Amount
$620,381.00
Summary
Cortical (outer shell) or compact bone constitutes 80% of the skeleton. It is not solid as implied by its name but made of inter-connected canals resembling a network of roads. We recently discovered that most of the bone loss with age occurs from these canals, not from t rabecular bone as currently believed. This suggests to know why and how bone breaks requires the study of the morphology of these canals and how they change with age. This is what we propose to do. It has never been done.
Novel Strategies For The Treatment Of Bone Disease By Nutrient Activators Of Calcium-sensing Receptors
Funder
National Health and Medical Research Council
Funding Amount
$467,432.00
Summary
Osteoporosis is a major health problem in the Australian community and will worsen with an ageing population. This work aims to develop new strategies for the treatment of osteoporosis and associated fractures based on the nutritional and/or pharmacological activation of calcium-sensing receptors.
Pain associated with bone cancer, fractures, osteoporosis, osteoarthritis, osteomyelitis (and other bone infections) often presents the clinician with a difficult problem of treatment as the pain can be debilitating and intractable. Most current treatments for bone pain are based on the assumption that the neural mechanisms underlying pain from different sources, whether it be visceral, cutaneous, muscular or bony, are the same, and can therefore be targeted with similar therapies. However, litt ....Pain associated with bone cancer, fractures, osteoporosis, osteoarthritis, osteomyelitis (and other bone infections) often presents the clinician with a difficult problem of treatment as the pain can be debilitating and intractable. Most current treatments for bone pain are based on the assumption that the neural mechanisms underlying pain from different sources, whether it be visceral, cutaneous, muscular or bony, are the same, and can therefore be targeted with similar therapies. However, little is known of the response properties, structure and organization of receptors and neurones responding to, and relaying information about painful stimuli, from bone to the brain. The objectives of this project are to reveal the fundamental neural mechanisms that account for the perception of bone pain. The project will test a series of specific hypotheses in order to explain why bone pain is often poorly controlled by standard pharmacological or surgical approaches. It is expected that this study will reveal the neural mechanisms responsible for relaying sensory information, in particular, that regarding painful stimuli, from bone to the brain. It will lead to a better understanding of the mechanisms of bone pain and form the template for future studies of its treatment.Read moreRead less
Trabecular Architecture During Growth - Does It Determine Metaphyseal Peak Bone Strength In Adulthood?
Funder
National Health and Medical Research Council
Funding Amount
$165,339.00
Summary
Skeletal fragility is common is elderly people but has its origin in childhood. Strong bone established during growth will provide more protection against occurrence of fragility fracture in old age. Identifying individuals during childhood who are at high risk of skeletal fragility, and early intervention is a strategic approach managing the burden of skeletal fragility on the ageing population.
The Molecular Mechanisms Controlling Maintenance Of Osteogenic Precursor Cells And Skeletal Tissue Regeneration
Funder
National Health and Medical Research Council
Funding Amount
$234,750.00
Summary
Within human bone marrow there exists a rare population of bone marrow stromal stem cells (BMSSCs) able to develop into the different cell types that form haematopoietic supportive stroma and surrounding skeletal tissue. There has been alot of interest of late in the potential of BMSSCs as a cellular based therapy to treat and manage bone fractures or bone loss caused by disease. Increasing evidence suggests that decreased bone mass due to osteoporosis dos not purely result in an increase of bon ....Within human bone marrow there exists a rare population of bone marrow stromal stem cells (BMSSCs) able to develop into the different cell types that form haematopoietic supportive stroma and surrounding skeletal tissue. There has been alot of interest of late in the potential of BMSSCs as a cellular based therapy to treat and manage bone fractures or bone loss caused by disease. Increasing evidence suggests that decreased bone mass due to osteoporosis dos not purely result in an increase of bone resorption by osteoclasts, but may also occur through a decline in the number of bone forming cells called osteoblasts or their progenitors. Fracture non-union, prosthetic loosening and the replacement of large defects in bone are common and difficult problems. The use of autologous bone cells generated from isolated BMSSCs in combination with bio-compatible implant materials would provide a novel solution for the treatment of these problems, avoiding the use of autografts and allografts of bone with all their associated difficulties. However, large numbers of ex vivo expanded BMSSCs are currently required to heal even small bone defects in animal models. This is compounded by the decline in proliferation rates and bone forming capacity of BMSSCs during prolonged expansion in culture. An improved understanding of the genes that regulate the proliferation and differentiation of BMSSCs in vitro is therefore an essential prerequisite for the effective management of bone fracture and bone loss. We propose to genetically manipulate the expression of genes in BMSSCs, that are known to regulate cellular growth and development inorder to maintain the growth of stem cell populations in vitro and to extend their capacity to form bone when transplanted in vivo.Read moreRead less
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
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