Characterisation Of The Regenerative Response In A Zebrafish Model Of Duchenne Muscular Dystrophy
Funder
National Health and Medical Research Council
Funding Amount
$435,750.00
Summary
Muscular Dystrophy is the most common lethal inherited disorder of children. Within dystrophic patients skeletal muscle fibres undergo cycles of muscle breakdown and regeneration until the regenerative response is exhausted, leading to a progressive muscle wasting. Regeneration of skeletal muscle is controlled by a specialised set of stem cells termed satellite cells that are activated to produce new muscle fibres in response to injury. As such satellite cells have been the targets of intense in ....Muscular Dystrophy is the most common lethal inherited disorder of children. Within dystrophic patients skeletal muscle fibres undergo cycles of muscle breakdown and regeneration until the regenerative response is exhausted, leading to a progressive muscle wasting. Regeneration of skeletal muscle is controlled by a specialised set of stem cells termed satellite cells that are activated to produce new muscle fibres in response to injury. As such satellite cells have been the targets of intense investigation for the development of cell based therapies for muscular dystrophies. We have developed a new vertebrate animal system in which to analyse muscular dystrophy and the control of satellite cell function, the zebrafish. We have shown that a mutation in a gene responsible for causing Duchenne Muscular Dystrophy in humans also causes a similar disease in Zebrafish. Zebrafish are an embryologically and genetically tractable model system in which to study muscle cell biology. The ability to visualise muscle growth within an optically transparent embryo and larvae, coupled with a large number of mutations affecting muscle patterning and growth suggest that it is a suitable model to explore muscle maintenance. The specific aims of this proposal are to determine in our new dystrophic zebrafish model, how regeneration controls the onset and pathology of muscle fibre loss. We wish to determine if muscle stems cells analogous to those known to function in mammalian muscle can be detected in zebrafish in normal and dystrophic muscle. We then plan to identify novel genes controlling muscle growth and regeneration through the genetic and embryological advantages that zebrafish as a model organism provide. We hope this will lead to a better understanding of how muscle stem cells are generated and are activated in muscular dystrophy and we hope this will open new avenues for muscle stem cell based therapies of the disease.Read moreRead less
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.
Genetic Basis For Skeletal Muscle Formation And Regeneration In Development And Disease
Funder
National Health and Medical Research Council
Funding Amount
$876,005.00
Summary
How does muscle grow and repair after injury or disease? This basic question in the focus of the research in this fellowship. Specific cells are put aside during development to generate the growth and provide stem cells required for regeneration. Using the advantages of the zebrafish system I will record the action of different stem cell populations during growth and disease. I will define the genes required for stem cell action and utilize this knowledge to create new therapeutic pathways.
Therapeutic Potential Of Skeletal Muscle Plasticity And Slow Muscle Programming For Muscular Dystrophy
Funder
National Health and Medical Research Council
Funding Amount
$780,476.00
Summary
There is no cure for DMD, a devastating, life-limiting muscle disease causing progressive muscle wasting in boys and young men. A potential therapy may come from modulating muscle activity patterns to promote a protective slow muscle phenotype through low-frequency stimulation protocols and/or well-described pharmacological ‘exercise mimetics’. This proposal will evaluate their therapeutic merit in mouse models of DMD to answer the key questions to advance this approach to the clinic.
Targeting Calcineurin For Improving Muscle Regeneration In Skeletal Muscle Disease
Funder
National Health and Medical Research Council
Funding Amount
$303,000.00
Summary
Muscular dystrophy is a term that covers a diverse group of inherited disorders characterised by progressive muscle weakness and wasting. Duchenne muscular dystrophy (DMD) is the most severe form, caused by a lack of a protein called dystrophin, which renders muscles fragile, susceptible to damage, and with a compromised ability to regenerate or repair after injury. The disease progresses to all muscles and DMD patients are dependent on a wheelchair before their early teens and die in their twen ....Muscular dystrophy is a term that covers a diverse group of inherited disorders characterised by progressive muscle weakness and wasting. Duchenne muscular dystrophy (DMD) is the most severe form, caused by a lack of a protein called dystrophin, which renders muscles fragile, susceptible to damage, and with a compromised ability to regenerate or repair after injury. The disease progresses to all muscles and DMD patients are dependent on a wheelchair before their early teens and die in their twenties. There is a profound need for treatments that can ameliorate the dystrophic condition and improve patient quality of life. Restoring or increasing a muscle's capacity to regenerate would help improve muscle function. We have convincing evidence that the calcineurin signal transduction pathway is important for successful muscle regeneration in mice with muscular dystrophy. There is growing excitement worldwide that stimulating calcineurin could attenuate the dystrophic pathology, however, little is known about the role of calcineurin signalling in human muscle disease. Our goals are to investigate the role of calcineurin signalling in muscular dystrophy and to examine its therapeutic potential for enhancing muscle regeneration. Our aim is to better understand the mechanisms controlling calcineurin signalling in muscles of dystrophic mice and in muscles of patients with DMD. A comprehensive series of physiological, molecular, biochemical, and immunohistochemical experiments will be performed to rigorously test our research aim. Understanding the role of the calcineurin pathway in muscle regeneration is important for the development of novel therapeutic strategies to delay the onset or slow the progression of muscle wasting and weakness. The findings will have broad clinical application for our understanding of muscular dystrophy with relevance to other conditions including ageing, AIDS, burns, cancer cachexia, and disuse atrophy, where muscle wasting occurs.Read moreRead less
Regulation Of Mammalian Heart Regeneration By The MiR-15 Family.
Funder
National Health and Medical Research Council
Funding Amount
$435,859.00
Summary
The inability of the adult heart to regenerate following a heart attack is a major contributor to the burden of heart disease in the developed world. We have recently discovered that, for a brief period after birth, the newborn heart can completely regenerate itself following injury. Understanding how and why the heart loses this remarkable capacity for regeneration shortly after birth may hold the key for developing cardiac regenerative therapies.
Therapeutic Potential Of Modulating Heat Shock Protein Expression For Muscle Wasting Disorder
Funder
National Health and Medical Research Council
Funding Amount
$1,172,146.00
Summary
Heat shock proteins help stressed proteins fold back to their original conformation and restore function. In a discovery published in Nature we identified induction of heat shock protein 72 (Hsp72) as a novel approach for muscular dystrophy and other conditions where there is inflammation and muscle weakness. This proposal will investigate whether Hsp72 induction is similarly effective in tackling the muscle wasting and weakness in conditions like ageing and frailty and in muscle injury.
We will apply genome-wide approaches to identify the gene networks that regulate the self-renewal and the differentiation of muscle stem cells and their fusion to muscle fibres. These studies will deliver the first characterisation of the molecules and pathways implicated in these processes, which are essential steps of muscle growth.
Mechanisms Of Muscle Stem Cell Action In Injury And Disease.
Funder
National Health and Medical Research Council
Funding Amount
$812,600.00
Summary
How do stem cells work in an organ or tissue to effect repair? Skeletal muscle is one of the few tissues that possesses the ability to regenerate after injury or disease but we understand very little about the processes that govern stem cell activation and the biology of self renewal, the mysterious process by which stem cell populations replicate themselves. Our zebrafish system will allow us to examine these questions directly in living muscle.