Regulatory mechanisms in skeletal muscle lipid hydrolysis. The regulation of intramuscular triglyceride (fat) utilisation by human skeletal muscle is largely unknown. Our contention is that the specialized protein enzyme, hormone sensitive lipase (HSL), has a fundamental role in intramuscular triacylglycerol utilisation and is regulated by both intramuscular levels of key metabolites and circulating hormone concentrations. We also propose control points subsequent to HSL activation are important ....Regulatory mechanisms in skeletal muscle lipid hydrolysis. The regulation of intramuscular triglyceride (fat) utilisation by human skeletal muscle is largely unknown. Our contention is that the specialized protein enzyme, hormone sensitive lipase (HSL), has a fundamental role in intramuscular triacylglycerol utilisation and is regulated by both intramuscular levels of key metabolites and circulating hormone concentrations. We also propose control points subsequent to HSL activation are important for triglyceride hydrolysis. Our proposed project examines these factors and will enhance our understanding of the regulation of muscle fat use, thereby leading to potential metabolic strategies (nutritional, pharmacological) that enhance skeletal muscle function at rest and during exercise.Read moreRead less
Biological Role of Contraction-Induced Heat Shock Protein Expression. It is well known that mammalian skeletal muscle increases its expression of a group of highly conserved proteins, the heat shock proteins (HSP) in response to repeated contraction. However, the biological role of this expression is unclear. The aim of this project is to determine the biological role of contraction-induced HSP expression. We expect to show that HSP synthesis in response to exercise has three major roles; 1) to ....Biological Role of Contraction-Induced Heat Shock Protein Expression. It is well known that mammalian skeletal muscle increases its expression of a group of highly conserved proteins, the heat shock proteins (HSP) in response to repeated contraction. However, the biological role of this expression is unclear. The aim of this project is to determine the biological role of contraction-induced HSP expression. We expect to show that HSP synthesis in response to exercise has three major roles; 1) to act to repair damaged proteins in recovery from muscle injury 2) to act as a "molecular motor" to translocate proteins from one region of a muscle cell to another and 3) to be released into the circulation in order to act as a central signal to activate immune cells. Such a project will be significant because it will allow for a fundamental understanding as to why these proteins are produced in response to exercise. We expect to enhance our understanding of fundamental cell biology.Read moreRead less
Reducing the fat burden: Identification of novel cellular and molecular targets for alleviating skeletal muscle insulin resistance. Insulin resistance and the associated consequences are a major public health problem in Australia and cost the healthcare system >$1.1 billion/year. Exercise training and thiaziolidinedione (TZD) treatment are therapies that partially ameliorate insulin resistance through distinct and independent mechanisms. However, neither intervention represents a viable long-ter ....Reducing the fat burden: Identification of novel cellular and molecular targets for alleviating skeletal muscle insulin resistance. Insulin resistance and the associated consequences are a major public health problem in Australia and cost the healthcare system >$1.1 billion/year. Exercise training and thiaziolidinedione (TZD) treatment are therapies that partially ameliorate insulin resistance through distinct and independent mechanisms. However, neither intervention represents a viable long-term strategy: exercise training has low compliance, while chronic TZD use is associated with several adverse side effects (edema, weight gain etc.). We will investigate the metabolic, cellular and molecular mechanisms by which these therapies each exert their positive effect on insulin action with the aim of identifying novel targets for future drug interventions. Read moreRead less
Intracellular localisation of insulin signalling proteins in human skeletal muscle following exercise. The metabolic action of insulin in skeletal muscle is enhanced by exercise, but the underlying mechanisms mediating this are unknown. Insulin receptor substrate proteins are key mediators in the intracellular insulin signalling pathway and play a central role in regulating many metabolic events. Our aim is to examine the hypothesis that exercise induces a novel subcellular redistribution of the ....Intracellular localisation of insulin signalling proteins in human skeletal muscle following exercise. The metabolic action of insulin in skeletal muscle is enhanced by exercise, but the underlying mechanisms mediating this are unknown. Insulin receptor substrate proteins are key mediators in the intracellular insulin signalling pathway and play a central role in regulating many metabolic events. Our aim is to examine the hypothesis that exercise induces a novel subcellular redistribution of these insulin receptor substrate proteins in skeletal muscle, such that the metabolic action of insulin is enhanced. Elucidating the mechanisms whereby exercise enhances insulin action underpins the development of new treatments and therapies with the aim of improving skeletal muscle function in health and disease.Read moreRead less
Coping With Pressure: Respiratory Biology of Marine Mammals. Many marine mammals undergo severe, protracted lung collapse during deep dives. They also exhibit prolonged periods of apnea during sleep. In humans, lung collapse and sleep apnea both represent severe respiratory dysfunction. Pulmonary surfactant, a complex mixture that lines the lung, stabilises the lungs in terrestrial mammals, preventing lung collapse. Here, we propose a comprehensive examination of respiratory function in marine m ....Coping With Pressure: Respiratory Biology of Marine Mammals. Many marine mammals undergo severe, protracted lung collapse during deep dives. They also exhibit prolonged periods of apnea during sleep. In humans, lung collapse and sleep apnea both represent severe respiratory dysfunction. Pulmonary surfactant, a complex mixture that lines the lung, stabilises the lungs in terrestrial mammals, preventing lung collapse. Here, we propose a comprehensive examination of respiratory function in marine mammals. This study will significantly advance our knowledge of the diving physiology of Australian marine mammals. A detailed examination of the respiratory and surfactant systems of marine mammals may also reveal adaptations that enable these animals to endure sleep apnea and lung collapse.Read moreRead less
Relaxin: molecular mechanisms of action in the reversal of fibrosis. Defects in relaxin and relaxin receptors are increasingly implicated as a cause of fibrosis which is associated with many disease processes. This study will examine the molecular mechanisms linking relaxin and fibrosis and will determine whether relaxin can be used to reverse the condition.
SKELETAL MUSCLE: REVERSIBLE TEMEPERATURE-INDUCED UNCOUPLING OF CONTRACTION FROM THE ACTIVATOR Ca2+ AND TUBULAR SYSTEM ROLES IN MUSCLE FUNCTION REGULATION. Skeletal muscles represent the largest organ in the body of vertebrates and are responsible for major functions including maintaining posture and locomotion. Skeletal muscles are also a major source of heat production. The project focuses on temperature-induced effects on the ability of the skeletal muscle to contract in warm blooded animals, ....SKELETAL MUSCLE: REVERSIBLE TEMEPERATURE-INDUCED UNCOUPLING OF CONTRACTION FROM THE ACTIVATOR Ca2+ AND TUBULAR SYSTEM ROLES IN MUSCLE FUNCTION REGULATION. Skeletal muscles represent the largest organ in the body of vertebrates and are responsible for major functions including maintaining posture and locomotion. Skeletal muscles are also a major source of heat production. The project focuses on temperature-induced effects on the ability of the skeletal muscle to contract in warm blooded animals, including marsupials, and on the complex roles played by a cellular structure unique to the muscle fibre, the tubular system, with respect to regulation of muscle function at physiological temperatures. The project will test hypotheses that will have far-reaching implications for muscle physiology, cell biology and evolutionary biology.Read moreRead less
Natriuretic peptide hormones and the stress response of fish. There are two main benefits of our research to Australia. Firstly, the team that we have assembled have international reputations, and include scientists from overseas. This team will be led by Australian Institutions and will put Australian science in the forefront of a competitive field, internationally. Secondly, our research examines questions that are critical in our understanding of how animals respond to stressful events. T ....Natriuretic peptide hormones and the stress response of fish. There are two main benefits of our research to Australia. Firstly, the team that we have assembled have international reputations, and include scientists from overseas. This team will be led by Australian Institutions and will put Australian science in the forefront of a competitive field, internationally. Secondly, our research examines questions that are critical in our understanding of how animals respond to stressful events. The response to stress, if excessive, leads to ill-health in both humans and other animals. Our research examines new connections between stress and fish biology, which could lead to discoveries that are valuable in managing stress and health in wild and farmed fishes.Read moreRead less
Cross-bridge cycling-dependent activation of force production in the absence of Ca2+ in fast- and slow-twitch skeletal muscle fibre types. The project will contribute new knowledge about how skeletal muscle works, which will be published in top international journals in biological sciences. This will increase the reputation of Australian science in muscle research and will have the potential to benefit Australian people and Australian athletes. The project will also provide several Australian re ....Cross-bridge cycling-dependent activation of force production in the absence of Ca2+ in fast- and slow-twitch skeletal muscle fibre types. The project will contribute new knowledge about how skeletal muscle works, which will be published in top international journals in biological sciences. This will increase the reputation of Australian science in muscle research and will have the potential to benefit Australian people and Australian athletes. The project will also provide several Australian research students the opportunity to develop sophisticated laboratory and reasoning skills.Read moreRead less
Anti-ageing role for relaxin in blood vessels. Arteries stiffen with age. This is due to increased arterial smooth muscle tone and alterations in the extracellular matrix. In a sense, the artery undergoes ?fibrosis? with aging. In light of the anti-fibrotic attributes of the peptide hormone relaxin observed in other tissues, this collaborative project will investigate the potential role for relaxin in opposing arterial ?fibrosis? associated with aging. We will test the hypothesis that a reductio ....Anti-ageing role for relaxin in blood vessels. Arteries stiffen with age. This is due to increased arterial smooth muscle tone and alterations in the extracellular matrix. In a sense, the artery undergoes ?fibrosis? with aging. In light of the anti-fibrotic attributes of the peptide hormone relaxin observed in other tissues, this collaborative project will investigate the potential role for relaxin in opposing arterial ?fibrosis? associated with aging. We will test the hypothesis that a reduction in arterial relaxin expression in older animals is a major cause of arterial stiffening. Further studies will investigate the mechanisms by which relaxin administration can alleviate this phenomenon.Read moreRead less