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..
The Role Of P62/A170 In Pathological Bone Destruction
Funder
National Health and Medical Research Council
Funding Amount
$276,000.00
Summary
Approximately up to 30% of patients are admitted to public hospitals in Australia for reasons related to skeletal disorders, including trauma, osteoarthritis, osteoporosis, primary and secondary bone tumours, genetic and metabolic disorders. Abnormal bone resorption contributes to most of these diseases and conditions. Based on the clinical evidence of P62 mutation in patients with Paget's Disease of bone and our observation of the involvement of P62 in RANKL-induced NF-Kb signaling, we propose ....Approximately up to 30% of patients are admitted to public hospitals in Australia for reasons related to skeletal disorders, including trauma, osteoarthritis, osteoporosis, primary and secondary bone tumours, genetic and metabolic disorders. Abnormal bone resorption contributes to most of these diseases and conditions. Based on the clinical evidence of P62 mutation in patients with Paget's Disease of bone and our observation of the involvement of P62 in RANKL-induced NF-Kb signaling, we propose that intracellular molecule P62-A172 may play an important part in the switch off-on signals necessary for bone resorbing cells to resorb bone. To this end, we will study the molecular mechanism of P62 in action, and the interaction with its possible partners for the facilitation of abnormal bone resorption. The clinical significance of this project is to: 1) enhance understanding of abnormal bone resorption in Orthopaedic related diseases and conditions. 2) provide a strategy of drug development for the treatment of these disease and conditions.Read moreRead less
The Molecular And Cellular Mechanisms Responsible For The Skeletal Complications Associated With Multiple Myeloma.
Funder
National Health and Medical Research Council
Funding Amount
$212,036.00
Summary
Multiple myeloma is an incurable disease of the antibody-producing B cell. Patients with MM, nearly always present with bone pain and unexplained bone fractures. These fractures are caused by the cancerous MM B cells, which are found in large numbers in discrete pockets throughout the bone marrow, close to the inner bone surface. The way that the cancerous B cells cause the local bone lesions is thought to be through the heightened activation of recruitment of osteoclasts. Osteoclasts are cells ....Multiple myeloma is an incurable disease of the antibody-producing B cell. Patients with MM, nearly always present with bone pain and unexplained bone fractures. These fractures are caused by the cancerous MM B cells, which are found in large numbers in discrete pockets throughout the bone marrow, close to the inner bone surface. The way that the cancerous B cells cause the local bone lesions is thought to be through the heightened activation of recruitment of osteoclasts. Osteoclasts are cells which normally, in a controlled manner, resorb bone as part of the ongoing process of new bone formation. We propose that myeloma cells, which exhibit characteristics of osteoclasts, home to sites in the bone marrow and initiate this bone breakdown and furthermore secrete factors required for osteoclast maturation and activity. We believe that these molecules include the recently defined molecule, termed osteoclast differentiation factor, which is normally produced by bone-producing cells known as osteoblasts. Moreover, we feel that myeloma B cells alter the function of osteoblast cells, which results in a decrease in bone formation. Finally, we propose that this disease and its associated bone defects originate from changes in the expression of a number of genes. The results from theses studies should provide a greater understanding of the way in which this B cell cancer originates and how it causes bone defects. This will lead to the development of better treatments to improve the survival of patients with MM, and will lead to therapies to prevent the associated bone complications.Read moreRead less
The Role Of CXCL12 (SDF-1)/CXCR4 In Pathological Angiogenesis And Osteolytic Bone Disease In Multiple Myeloma
Funder
National Health and Medical Research Council
Funding Amount
$665,896.00
Summary
Multiple myeloma (MM) is the second most common haematological (or blood) cancer in western countries and is unique amongst blood cancers in its capacity to destroy the skeleton. MM is a cancer of plasma cells, which in their normal non-cancerous form, reside in lymph nodes and produce antibodies against infectious agents. When they become cancerous, they migrate or home to congenial sites within the bone marrow (BM). This directed movement or homing occurs under the influence of a chemokine mol ....Multiple myeloma (MM) is the second most common haematological (or blood) cancer in western countries and is unique amongst blood cancers in its capacity to destroy the skeleton. MM is a cancer of plasma cells, which in their normal non-cancerous form, reside in lymph nodes and produce antibodies against infectious agents. When they become cancerous, they migrate or home to congenial sites within the bone marrow (BM). This directed movement or homing occurs under the influence of a chemokine molecule called CXCL12 which acts as a calling card for plasma cells to leave the lymph node and migrate to the BM. Once within the BM, the cells rapidly grow in response to BM-derived growth factors. This rapid growth causes a depletion in oxygen availability within the tumour and it becomes hypoxic. In response to this hypoxia, the tumour expresses a gene called hypoxia-inducible factor-1 (HIF-1) which regulates the expression of many proteins, including the chemokine CXCL12. Our studies show that the abnormal expression of CXCL12 by the plasma cells acts to promote blood vessel formation within the tumour, which in turn leads to greater tumour growth. In addition, our studies suggest that abnormal CXCL12 expression also promotes the recruitment and activation of large numbers of osteoclast (OC) precursors form the peripheral blood. OC are cells which normally remove unwanted or damaged bone. This proposal will study the interplay between HIF and CXCL12 in the establishment and development of MM and the associated bone destruction.Read moreRead less
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.