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.
Influence Of Osteocytes On Anabolic Bone Therapies
Funder
National Health and Medical Research Council
Funding Amount
$586,965.00
Summary
This project seeks to define the influence of changes in gene expression in cells called osteocytes, that exist within the substance of bone. These cells form a communication network within the bones of the skeleton, and appear to influence bone formation; changes in gene expression by these cells could influence the efficacy of current and emerging osteoporosis therapies.
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
Osteal Macrophages As Therapeutic Targets For Fracture Repair
Funder
National Health and Medical Research Council
Funding Amount
$618,015.00
Summary
Fragility fracture associated with osteoporosis is a substantial health problem costing $1.62 billion to treat in 2012 in Australia. There is no approved therapy to improve and accelerate fracture healing to help reduce this increasing health burden. This research will advance understanding of fracture repair in healthy and osteoporotic bone and progress development of a fracture therapy to improve bone repair by promoting specialised immune cells.
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
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
Why Macrophages Promote Heterotopic Ossifications Following Spinal Cord Injuries
Funder
National Health and Medical Research Council
Funding Amount
$586,950.00
Summary
A frequent complications of brain and spine injuries is the formation of bones outside of the skeleton called "heterotopic ossifications", particularly around joints such as the knee, hip, elbow or shoulder. They grow over a few months to become so large (up to 2 kg) that they block muscles and joints, increasing pain, morbidity and dependance. This project is to understand why heterotopic ossifications form in patients with spine injuries aiming to discover effecttive treatments.
The Role Of Androgens In Osteoblast Development And Bone Metabolism.
Funder
National Health and Medical Research Council
Funding Amount
$487,500.00
Summary
Maintenance of the skeleton involves the processes of bone formation by cells known as osteoblasts and bone breakdown by cells known as osteoclasts. When these processes become unbalanced, bone loss results, which is the basis of osteoporosis. The reduced bone mass found in osteoporosis leads to an increased susceptibility to bone fracture. 1 in 2 women and 1 in 3 men over the age of 60 will suffer a fracture due to osteoporosis. The increasing incidence of osteoporotic fractures has lead to ren ....Maintenance of the skeleton involves the processes of bone formation by cells known as osteoblasts and bone breakdown by cells known as osteoclasts. When these processes become unbalanced, bone loss results, which is the basis of osteoporosis. The reduced bone mass found in osteoporosis leads to an increased susceptibility to bone fracture. 1 in 2 women and 1 in 3 men over the age of 60 will suffer a fracture due to osteoporosis. The increasing incidence of osteoporotic fractures has lead to renewed efforts to understand the actions of hormones on bone. Androgens, the male sex hormones, have beneficial effects on skeletal growth and bone maintenance in both males and females by stimulating osteoblasts. It is believed that androgens act by binding to a specific protein known as the androgen receptor (AR), which is only found in androgen-responsive cells. Although it is well documented in human and animal models that androgens stimulate osteoblasts to increase the formation of bone, the way in which they act on osteoblasts remains poorly understood. The aim of this project is to investigate the effects of androgens at different stages of the developing osteoblast. This will be achieved by making transgenic mice in which the androgen receptor has been inactivated only in osteoblasts at specific stages of their development. We hypothesise that the inactivation of the androgen receptor will have dramatic effects on the development and function of osteoblasts. This project will help clarify the role androgens play in bone formation and will give fundamental insights into the basic biology of bone in both normal and disease processes. As androgens are one of the few agents that act to increase bone formation, understanding the way in which they act is important for the treatment of osteoporosis in males and females. We believe that this research is of great importance as osteoporosis becomes more prevalent in our aging population.Read moreRead less
Osteal Macrophages: Novel Regulators Of Osteoblast Function And The Endosteal Stem Cell Niche
Funder
National Health and Medical Research Council
Funding Amount
$406,125.00
Summary
Bone diseases are a major health problem and current treatments are inadequate. We are investigating a novel role for macrophages (cells important in tissue maintenance and immune responses) in bone growth, repair and disease. Greater understanding of this will provide new ways to treat bone disease. We will also determine if these macrophages help support stem cells that reside near bone surfaces, which may provide new treatment strategies to improve bone marrow transplantation in cancer.
Failure of bone healing leads to significant pain and disability, such that augmentation of fracture repair is a dynamic and important field of study. A full understanding of bone repair is necessary before we can hope to introduce novel successful therapies. We believe that a improved understanding of the origins of the cells involved with bone healing may lead to new surgical, drug and cell-based therapies for the treatment of recalcitrant bone repair. Stem cells originating from the bone marr ....Failure of bone healing leads to significant pain and disability, such that augmentation of fracture repair is a dynamic and important field of study. A full understanding of bone repair is necessary before we can hope to introduce novel successful therapies. We believe that a improved understanding of the origins of the cells involved with bone healing may lead to new surgical, drug and cell-based therapies for the treatment of recalcitrant bone repair. Stem cells originating from the bone marrow and periosteum are known to differentiate into mature bone cells and produce bone. However, these tissues are damaged or have poor access to the site of bone injury in many severe open fractures. In these cases, bone repair often initiates in a region adjacent to an opposing muscle. This has led us to speculate that cells from the muscle may directly contribute to bone repair. Published studies, which have be confirmed by our group, have demonstrated the strong potential for muscle-derived progenitor cells (satellite cells) to become bone-like in response to stimuli such as bone morphogenic proteins. To put bone-forming potential of muscle cells in perspective, we plan to expand on these studies and compare mouse satellite cells with mouse bone marrow stem cells. In addition, we plan to use a transgenic mouse whose muscle cells become permanently genetically transformed to stain blue. This mouse will allow us to assess the fate of muscle cells and their contribution to bone formation in ectopic bone formation and fracture repair models. This study will explore on the most basic level the cellular contribution of muscle to bone repair. The results of this research project will significantly influence our therapeutic directions for improving fracture repair in the future.Read moreRead less