Establishing STARS As A Therapeutic Target To Reduce Muscle Wasting And Improve Muscle Function
Funder
National Health and Medical Research Council
Funding Amount
$446,189.00
Summary
Muscle wasting occurs rapidly with disuse after injuries occurring at work, during sport, with chronic disease and in road accidents. It is also a consequence of ageing. Muscle wasting and reduced muscle function places considerable financial strain on our health care system. We aim to use gene therapy and pharmacological interventions to increase the levels of a protein called STARS. We hypothesize that STARS will reduce disuse-induced muscle wasting, increase recovery and improve function.
Osteocytes, the most abundant and long-lived, yet least studied bone cell, are increasingly recognised as key controllers of bone remodelling and are implicated in many bone diseases. Our work is uncovering novel molecular and cellular pathways by which osteocytes act and survive in bone, which is generally an oxygen-deprived tissue. This will provide a rational basis to seek improved treatments of bone disease.
Deregulation Of DNA Hydroxymethylases Tet1/ Tet2 Compromises Skeletal Integrity During Ageing And Bone Disease
Funder
National Health and Medical Research Council
Funding Amount
$850,229.00
Summary
Epigenetic modifications of DNA and associated proteins regulate gene expression. A greater understanding of the molecular pathways and associated epigenetic changes that regulate bone cell commitment under normal and pathological conditions will help enhance our ability to diagnose and treat disorders/ diseases that effect skeletal tissues through the pharmacological manipulation of epigenetic modifiers and their gene targets.
gp130 is a protein expressed in all cells in the body; this project will analyse the influence of gp130 within the cells that form bone, the cells that destroy bone, and the cells that form a communication network within the bone matrix. Understanding the way this protein works will help us to understand how current therapies for osteoporosis work, and will help us to design new therapies.
The Role Of A Novel Extracellular Matrix Protein, WARP, In Cartilage Development, Function And Pathology
Funder
National Health and Medical Research Council
Funding Amount
$482,500.00
Summary
The environment outside all cells is absolutely essential for normal growth and development. In order to undertand many disease and developmental processes it is critical that we acquire a detailed understanding of the various extracellular matrix components and how they interact to form a functional extracellular matrix. We recently discovered a new extracellular matrix protein which we have named WARP for von Willebrand factor A-domain-related protein. Our experiments demonstrate that WARP is ....The environment outside all cells is absolutely essential for normal growth and development. In order to undertand many disease and developmental processes it is critical that we acquire a detailed understanding of the various extracellular matrix components and how they interact to form a functional extracellular matrix. We recently discovered a new extracellular matrix protein which we have named WARP for von Willebrand factor A-domain-related protein. Our experiments demonstrate that WARP is an important constituent of the three-dimensional structure of the extracellular matrix of the articular surface of cartilage. We can show that WARP forms large-scale structures in tissue culture experiments and in extracts from mouse cartilage, and we have some new data which suggests that WARP interacts specifically with collagen II, a large and quantitatively major component of cartilage. We will explore the function of WARP in cartilage and include in vitro experiments that will reveal information about its distribution, tissue forms, and interactions with other extracellular matrix components (PART 1). To define the in vivo role of WARP we will generate a WARP gene knockout mouse (PART 2). These experiments will provide valuable information about the structure of the cartilage in the joint on the surface of bone and in particular the function of WARP in this structure. Since WARP is at the articular cartilage surface we asked whether WARP is lost in cartilage degeneration. In cartilage tissue grown in vitro under conditions that promote cartilage degradation, WARP is fragmented and released from the cartilage surface. We will explore this further in in vitro and in vivo models of cartilage breakdown (PART 3). Thus, in addition to promoting a new understanding of cartilage structure WARP has the exciting potential to become a specific biomarker for arthritis a major joint degenerative disease with high medical and financial cost to the community.Read moreRead less
The Calcium Channel TRPV4 In Skeletal Development And Arthritis
Funder
National Health and Medical Research Council
Funding Amount
$683,069.00
Summary
We have discovered that mutations in a calcium channel gene, TRPV4, cause an inherited osteoarthritis in the hands and feet. This work suggests that TRPV4 may be important in osteoarthritis and suggests the exciting possibility that modulating TRPV4 activity may provide a new therapeutic approach for arthritis. We will study how and why the mutations disrupt channel function and study mouse models to see if they are more or less susceptible to arthritis.
Molecular Mechanisms Of Wasting In Experimental COPD
Funder
National Health and Medical Research Council
Funding Amount
$389,521.00
Summary
Chronic obstructive pulmonary disease (COPD) is a major global health problem and has been predicted to become the third largest cause of death in the world by 2020. Cigarette smoking is the major cause of COPD and accounts for more than 95% of cases in industrialized countries. Currently no therapies exist to halt the inevitable progression of the disease. To date most of the research has focused on the aspects of this disease which result in destruction of the lung however it is becoming incre ....Chronic obstructive pulmonary disease (COPD) is a major global health problem and has been predicted to become the third largest cause of death in the world by 2020. Cigarette smoking is the major cause of COPD and accounts for more than 95% of cases in industrialized countries. Currently no therapies exist to halt the inevitable progression of the disease. To date most of the research has focused on the aspects of this disease which result in destruction of the lung however it is becoming increasingly evident that COPD is a disease of multiple organs. Until recently it had been widely believed that the profound loss of exercise tolerance observed in COPD patients was due to impaired gas exchange secondary to lung structural damage. Loss of lean body mass (muscle) is now recognised as a major co-morbidity of COPD and a direct cause of functional impairment with patients suffering marked deteriorations in quality of life, increased mortality, breathlessness and decreased exercise tolerance. Skeletal muscle wasting is a powerful predictor of mortality in COPD, independent of the lung function impairment. Despite the clinical seriousness of muscle wasting and suggestive evidence that it may be reversible, little is known about the pathogenic mechanisms. Therefore the goal of this project is to use experimental models of COPD to identify the molecular basis of wasting, in order to restore skeletal muscle homeostasis. The insights gained from this research proposal may lead to the identification of potentially novel targets for the prevention and reversal of the debilitating and life threatening effects of skeletal muscle wasting in COPD. For the COPD patient this has the potential to increase quality of life, functional ability and life expectancy.Read moreRead less
Macrophages, Cytokines And The Inflammatory Response (Reappointment To Senior Principal Research Fellow)
Funder
National Health and Medical Research Council
Funding Amount
$898,008.00
Summary
The project will continue to explore how a type of white blood cell contributes to the pathology associated with chronic inflammatory diseases, such as rheumatoid arthritis, heart disease, atherosclerosis, multiple sclerosis and periodontal disease. Success already has been achieved in that clinical trials in rheumatoid arthritis have emanated from this project.
Mucopolysaccharidoses (MPS) are a related group of 11 debilitating genetic disorders affecting children. They result from a reduction or total deficiency of an enzyme required for the removal of carbohydrate structures called glycosaminoglycans (gags). Gag degradation occurs inside the cell in specific organelles termed lysosomes and in the absence of the appropriate enzyme, undegraded gag accumulates in the cell. This leads to a range of clinical symptoms and multiple tissue failure. Symptoms c ....Mucopolysaccharidoses (MPS) are a related group of 11 debilitating genetic disorders affecting children. They result from a reduction or total deficiency of an enzyme required for the removal of carbohydrate structures called glycosaminoglycans (gags). Gag degradation occurs inside the cell in specific organelles termed lysosomes and in the absence of the appropriate enzyme, undegraded gag accumulates in the cell. This leads to a range of clinical symptoms and multiple tissue failure. Symptoms common to more than one MPS type include mental deterioration, blindness, abdominal organ enlargement and bone growth problems leading to short stature and bone loss. My laboratory has had a long-term interest in developing treatment for MPS and our research led to the clinical implementation of enzyme replacement therapy (ERT) for MPS VI in 2005. While providing the first effective, multi-tissue treatment for MPS, our research showed that several tissues were not responsive to ERT. These are the brain, cartilage and cornea, thus children on ERT regimens will still suffer from mental retardation, arthritis and blindness. With the goal of treating these particular tissues we have developed a new approach to MPS therapy called substrate deprivation therapy (SDT). Instead of adding back the missing enzyme, SDT acts by decreasing gag production which in turn reduces the level of accumulated gag in cells. SDT results in the correction of MPS cells in culture and reduces several key clinical symptoms in the mouse model of MPS IIIA. In this proposal we will extend our research to evaluate the effect of SDT on brain and bone-joint pathology. Evaluation of efficacy will take place in the MPS VII mouse which exhibits both brain and bone disease and in a new model of MPS IVA developed specifically for this study which exhibits a joint pathology unique amongst the MPS disorders.Read moreRead less
Molecular Pathology Of Collagen VI-related Muscular Dystrophies
Funder
National Health and Medical Research Council
Funding Amount
$574,500.00
Summary
The inherited muscular dystrophies, characterised by progressive muscle weakness and wasting, are a significant cause of physical disability. Muscle cells are anchored into the surrounding tissue by a chain of interacting proteins. Proteins inside the cell link to cell surface proteins, which in turn link to extracellular matrix proteins. If any one of the links is broken by a mutation, the connection is lost and muscle disease results. Most studies to date have focused on the role of intracellu ....The inherited muscular dystrophies, characterised by progressive muscle weakness and wasting, are a significant cause of physical disability. Muscle cells are anchored into the surrounding tissue by a chain of interacting proteins. Proteins inside the cell link to cell surface proteins, which in turn link to extracellular matrix proteins. If any one of the links is broken by a mutation, the connection is lost and muscle disease results. Most studies to date have focused on the role of intracellular and cell surface proteins, and relatively little attention has been paid to the extracellular matrix proteins. Mutations in the extracellular matrix protein collagen VI have been found in patients with Bethlem myopathy and Ullrich muscular dystrophy. These mutations tell us that collagen VI plays a critical role in muscle but we don't know how the mutations break the link between the cell and the matrix or why they cause a muscle disease. We will look for collagen VI mutations in our group of new Bethlem myopathy and Ullrich patients, and perform detailed studies on the effect of the mutations on collagen VI production, structure and function. These studies will allow us to provide accurate diagnosis and genetic counselling for affected individuals and begin to tell us how the mutations break the cell-matrix link. Mutations in other extracellular matrix proteins that interact with collagen VI are also likely to cause muscular dystrophies. One of these proteins is biglycan. We know from studies in mice that when biglycan is missing the mice have muscular dystrophy, so it is likely that some human muscular dystrophy patients have biglycan mutations. We will look for biglycan mutations in patients with muscular dystrophies and perform detailed studies to try to understand the effect of the mutations on the biglycan protein. This application brings together two groups with complementary expertise, to further our understanding of the basis of muscular dystrophies.Read moreRead less