The Role Of EphrinB1 Reverse Signalling In Osteogenic Differentiation During Skeletal Development And Osteoporosis
Funder
National Health and Medical Research Council
Funding Amount
$567,292.00
Summary
The present proposal will identify the importance of ephrinB1 during the deregulation of bone remodelling that occurs in osteoporosis, by deleting ephrinB1 in committed osteoblast precursor cells in a mouse model of osteoporosis. Knowledge gained from this proposal could potentially translate into alternative therapeutic treatment strategies for patients with osteoporosis with the use of Eph/ephrin targeted drugs currently being developed for cancer treatment.
Sclerostin: A Key Regulator Of Bone Mineralisation And Bone Catabolism
Funder
National Health and Medical Research Council
Funding Amount
$536,653.00
Summary
The regulation of bone mass is critical for many areas of human disease including osteoporosis, osteoarthritis, inflammatory bone loss conditions, e.g. rheumatoid arthritis, cancers of bone and problems relating to orthopaedic prosthesis failure. The osteocyte, the most abundant bone cell, plays a central role in normal bone biology and is likely key to these diseases. Sclerostin is one osteocyte product that may be a key to understanding how boneÍs mass and composition is controlled locally.
Experimental And Computational Study On Biomechanical Behavior Of Osteocytes
Funder
National Health and Medical Research Council
Funding Amount
$86,073.00
Summary
The experimental and computational methods (finite element method) are used to predict biomechanical behaviors of osteocytes under normal physiological loading, overloading or under-loading/disuse. This quantitative research will not only help to elucidate the mechanisms of mechanotransduction in osteocytes, it will provide important information that is also relevant to mechanobiology in general.
Assessment Of The Properties Of Mesenchymal Stem Cells And Their Role In Skeletal Tissue Repair And Disease
Funder
National Health and Medical Research Council
Funding Amount
$751,854.00
Summary
There is currently a steady increase in surgical intervention and rehabilitation therapy for bone related fractures due to trauma or osteoporosis as a consequence of an aging population. Bone regeneration involves the coordinated participation of skeletal precursor cells, blood vessels and immune cells recruited from the surrounding tissues. This proposal examines the mechanisms mediating the maintenance and recruitment of skeletal precursor cells to sites of bone damage.
Tyrosine Kinase Receptor C-ros-oncogene 1 Mediates Twist-1 Haploinsufficiency Induced Craniosynostosis In Children: A Novel Therapeutic Target
Funder
National Health and Medical Research Council
Funding Amount
$562,863.00
Summary
Children with Saethre-Chotzen syndrome exhibit premature fussed coronal sutures, and other skull/ skeletal malformations. Surgical intervention is the only treatment option to ensure optimal cognitive and skeletal development. Our studies have identified a candidate molecular pathway that regulates bone formation by cranial bone cells from these patients. Targeting these key molecular signalling components with chemical inhibitors will help prevent the premature fusion of cranial sutures.
The Role Of Sorting Nexin 27 In Cargo-trafficking During Skeletal Homeostasis
Funder
National Health and Medical Research Council
Funding Amount
$623,327.00
Summary
Skeletal diseases encompass a devastating set of disorders ranging from heritable skeletal dysplasia’s such as dwarfism through to degenerate diseases like osteoporosis. This research project aims to determine the role of a protein called Sorting Nexin 27 (SNX27), normally involved in the transport of intracellular cargo (e.g. growth factor receptors), in the maintenance of the skeleton and its potential contribution to the pathogenesis of skeletal disorders.
Osteoclasts (OC) are large multinucleated cells present in bone that are responsible for bone resorption. The renewal of bone and bone growth are regulated by the opposing actions of OCs and osteoblasts, cells that form new bone. Together, with other accessory cells in the bone marrow, these constitute 'bone-forming units' (BFU). Excess production or over-activation of OCs in the BFU leads to common bone conditions such as osteoporosis, Paget's disease and the bone lysis caused by bone cancers. ....Osteoclasts (OC) are large multinucleated cells present in bone that are responsible for bone resorption. The renewal of bone and bone growth are regulated by the opposing actions of OCs and osteoblasts, cells that form new bone. Together, with other accessory cells in the bone marrow, these constitute 'bone-forming units' (BFU). Excess production or over-activation of OCs in the BFU leads to common bone conditions such as osteoporosis, Paget's disease and the bone lysis caused by bone cancers. Osteoporosis causes a great deal of pain and disability and it alone costs the Australian taxpayers more than $400 million per year. OCs are formed from white blood cells that are present in the bone marrow and the blood. The recent discovery of a family of new factors that control the formation of OCs has enabled the generation of human OCs in the laboratory so now we can investigate the genes that control the process of conversion of white blood cells to OCs. An important advance in this project involves the use of cord blood that contains stem cells. These very na ve cells will enable us to study the very earliest genes that control differentiation of precursors to OC. We have found a number of genes that are regulated by these new bone-forming factors. In white blood cells the activation of particular genes can regulate OC formation. One example is vitamin D-upregulated gene, VDUP. This gene is of particular interest as it causes inhibition of the mechanism that leads to OC formation in the bone. Obviously, the ability to control a 'switch' that regulates OC formation may enable us to control the progress of bone loss in diseases such as osteoporosis. In this project, we intend to investigate how and why the genes that lead to OC formation are regulated and what influence the various bone cell factors have on the formation of bone-resorbing OCs. These studies will lead to the development of treatments for osteoporosis and other bone diseases.Read moreRead less
Histone Demethylase KDM6A Is A Novel Target For Treating Craniosynostosis In Children With Saethre-Chotzen Syndrome
Funder
National Health and Medical Research Council
Funding Amount
$548,854.00
Summary
Children with Saethre-Chotzen syndrome exhibit premature fused coronal sutures, and other skull/ skeletal malformations. Surgical intervention is the only treatment option to ensure optimal cognitive and skeletal development. Our studies have identified a candidate molecular pathway that regulates bone formation by cranial bone cells from these patients. Targeting this key molecular regulator with chemical inhibitors will help prevent the premature fusion of cranial sutures.
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 Osteocytes In Particle Induced Osteolysis
Funder
National Health and Medical Research Council
Funding Amount
$457,196.00
Summary
Hip replacements often fail due to the loss of adjacent bone. Metal or polyethylene particles are produced as the prosthesis bearing surface wears but how do these particles lead to bone loss? Our work suggests involvement of osteocytes within the bone mineral, which are increasingly understood to drive bone physiology and pathology. We will explore the role of the osteocytes by examining their response to particles, which may identify a new target to prevent particle-induced bone loss.