Modulating the molecular and cellular physiology of ageing skeletal muscle. Understanding the underlying mechanisms of how ageing affects muscle is of increasing importance to the community as the number of older persons in the population continues to escalate and the age of retirement increases. Old muscles are slower and weaker than young muscles, and are more easily injured. This proposal is focussed on developing safe therapies to prevent or reverse these age-related effects. Making old musc ....Modulating the molecular and cellular physiology of ageing skeletal muscle. Understanding the underlying mechanisms of how ageing affects muscle is of increasing importance to the community as the number of older persons in the population continues to escalate and the age of retirement increases. Old muscles are slower and weaker than young muscles, and are more easily injured. This proposal is focussed on developing safe therapies to prevent or reverse these age-related effects. Making old muscles young again, is a research strategy that will promote healthy ageing and enable older Australians to enjoy a better quality of life.Read moreRead less
Estrogen signalling in gonadotropes. Estrogen action is a normal prerequisite for cyclic function of reproduction in the female, but little is known about how this important hormone acts in the relevant cells of the pituitary gland (gonadotropes). In order to gain information on normal function, we will conduct studies on gonadotropes treated with estrogen in a range of paradigms. The information will be valuable in understanding normal reproduction, but will also form the basis of further studi ....Estrogen signalling in gonadotropes. Estrogen action is a normal prerequisite for cyclic function of reproduction in the female, but little is known about how this important hormone acts in the relevant cells of the pituitary gland (gonadotropes). In order to gain information on normal function, we will conduct studies on gonadotropes treated with estrogen in a range of paradigms. The information will be valuable in understanding normal reproduction, but will also form the basis of further studies to investigate the effects of drugs that affect estrogen action and environmental estrogens. Read moreRead less
Regenerating lizard tails: A model for understanding the process of lymphangiogenesis. In humans, impaired lymphatic drainage in limbs causes the debilitating swelling termed lymphoedema. Lymphoedema affects 500,000,000 people worldwide. In the developed world lymphoedema predominantly results from surgery for cancer, and occurs in approximately 25% of breast cancer patients. We will examine lymph vessel regeneration (lymphangiogenesis) in a naturally regenerating, complex structure (the lizard ....Regenerating lizard tails: A model for understanding the process of lymphangiogenesis. In humans, impaired lymphatic drainage in limbs causes the debilitating swelling termed lymphoedema. Lymphoedema affects 500,000,000 people worldwide. In the developed world lymphoedema predominantly results from surgery for cancer, and occurs in approximately 25% of breast cancer patients. We will examine lymph vessel regeneration (lymphangiogenesis) in a naturally regenerating, complex structure (the lizard tail), to describe the regrowth process and determine the abundance, location, functional properties and molecular control of the new lymphatics. Furthermore, if reptilian lymphatic growth factors can promote lymphangiogenesis in mammals, we can design novel therapeutic approaches using reptilian ligands to promote lymphangiogenesis in lymphoedematous human tissues.Read moreRead less
Unified framework of intestinal motility. The project aims to establish how a few fundamental mechanisms determine the large repertoire of intestinal motor patterns responsible for moving nutrients along the digestive tract. The project will combine experimental and theoretical data, with biomechanical and electrophysiological models to create a new understanding of this essential function of the body.
Electrophysiological and Anatomical Characterization of the Coronary Sinus Musculature and its Relationship to the Atria. This series of experiments will characterise the normal coronary sinus musculature and its connectivity to the atria of the heart and establish their electrical relationships. The underlying characteristics of the muscular connections will also be evaluated with a view to possible future manipulations of the system. Understanding normal heart impulse propagation is paramount ....Electrophysiological and Anatomical Characterization of the Coronary Sinus Musculature and its Relationship to the Atria. This series of experiments will characterise the normal coronary sinus musculature and its connectivity to the atria of the heart and establish their electrical relationships. The underlying characteristics of the muscular connections will also be evaluated with a view to possible future manipulations of the system. Understanding normal heart impulse propagation is paramount before we can understand and develop treatments for dealing with heart problems. This information will facilitate the development of techniques to treat and prevent heart rhythm disorders that are a common cause of morbidity in the community.Read moreRead less
Does muscle contribute to the maintenance of vitamin D status in winter? This project aims to test the mechanism by which vitamin D status is maintained in winter when input is low. The long half-life in blood of the vitamin D metabolite, 25-hydroxyvitamin D [25(OH)D], maintains an adequate vitamin D status over winter, when sunlight, which produces vitamin D in skin, is reduced. From preliminary data in sheep and mice, this project proposes that skeletal muscle, not fat, stores vitamin D. This ....Does muscle contribute to the maintenance of vitamin D status in winter? This project aims to test the mechanism by which vitamin D status is maintained in winter when input is low. The long half-life in blood of the vitamin D metabolite, 25-hydroxyvitamin D [25(OH)D], maintains an adequate vitamin D status over winter, when sunlight, which produces vitamin D in skin, is reduced. From preliminary data in sheep and mice, this project proposes that skeletal muscle, not fat, stores vitamin D. This project will test this hypothesis in sheep, cultured muscle cells and in transgenic mice. The project will confirm whether the processes identified in skeletal muscle contribute to the maintenance of vitamin D status, and identify ways of enhancing this process.Read moreRead less
Microparticles as effectors of microvascular alterations in brain inflammation. Cerebral malaria (CM) kills many children worldwide, but we do not understand why their small blood vessels in the brain become obstructed. We found that tiny elements detached from cell membranes, called microparticles (MP), are dramatically elevated in the blood during CM. Our results strongly suggest that these MP are important in CM development. We have found that some drugs block the release of MP and the stick ....Microparticles as effectors of microvascular alterations in brain inflammation. Cerebral malaria (CM) kills many children worldwide, but we do not understand why their small blood vessels in the brain become obstructed. We found that tiny elements detached from cell membranes, called microparticles (MP), are dramatically elevated in the blood during CM. Our results strongly suggest that these MP are important in CM development. We have found that some drugs block the release of MP and the stickiness of malaria parasites to blood vessels. Our project will tackle the conditions of MP production and define new drugs to prevent it. It also will explain how the brain becomes affected by high numbers of MP. Our results will cast new light on why the brain functions abnormally when its blood vessels become modified.Read moreRead less
Blood flow routes in muscle. Ageing well, ageing productively. The Australian population is ageing. The proportion of the population over the age of 65 is expected to greatly increase, reaching 22% by the year 2030. The prevalence of type 2 diabetes in this older population is thought to be ~20%, compared to ~6% in younger populations. An initial cause of type 2 diabetes may be microvascular dysfunction brought on by physical inactivity. Therefore this project addresses the concepts of microvasc ....Blood flow routes in muscle. Ageing well, ageing productively. The Australian population is ageing. The proportion of the population over the age of 65 is expected to greatly increase, reaching 22% by the year 2030. The prevalence of type 2 diabetes in this older population is thought to be ~20%, compared to ~6% in younger populations. An initial cause of type 2 diabetes may be microvascular dysfunction brought on by physical inactivity. Therefore this project addresses the concepts of microvascular function and microvascular fitness by using the latest technology to map blood flow routes in muscle under a number of relevant situations. Read moreRead less
Microdialysis for monitoring changes in microvascular flow patterns in muscle. Microdialysis is a technique for sampling interstitial fluid. Factors altering vascular delivery and removal of nutrients and hormones can affect muscle metabolism by altering exchange with the interstitium. This project focuses on microdialysis for assessing the impact of microvascular blood flow patterns on skeletal muscle metabolism and contractility. The aim is to develop and refine the technology, including equat ....Microdialysis for monitoring changes in microvascular flow patterns in muscle. Microdialysis is a technique for sampling interstitial fluid. Factors altering vascular delivery and removal of nutrients and hormones can affect muscle metabolism by altering exchange with the interstitium. This project focuses on microdialysis for assessing the impact of microvascular blood flow patterns on skeletal muscle metabolism and contractility. The aim is to develop and refine the technology, including equations, specifically for monitoring the nutritive fraction of blood flow in muscle by agents and factors relating to health and disease. This technique could be used for screening drugs in the treatment of diseases such as type 2 diabetes and related conditions.Read moreRead less
Impact of shear stress on vascular adaptations in humans. Large arteries are important for the delivery of blood and oxygen to organs such as the heart and brain. A primary physiological stimulus which controls the size and function of these crucial arteries is the magnitude of flow or, more accurately, shear force that the inner wall of the artery is exposed to. We have developed novel software which enables non-invasive assessment of arterial wall velocity, diameter and blood flow. We will ass ....Impact of shear stress on vascular adaptations in humans. Large arteries are important for the delivery of blood and oxygen to organs such as the heart and brain. A primary physiological stimulus which controls the size and function of these crucial arteries is the magnitude of flow or, more accurately, shear force that the inner wall of the artery is exposed to. We have developed novel software which enables non-invasive assessment of arterial wall velocity, diameter and blood flow. We will assess the impact of acute and chronic changes in wall flow and shear on arterial size and function. We will also develop new software which measures other aspects of artery wall behaviour. These basic human physiology studies have direct implications for assessment of artery health in humans.Read moreRead less