Mitochondrial Sirtuins, Energy Metabolism And Insulin Action
Funder
National Health and Medical Research Council
Funding Amount
$582,925.00
Summary
Post-translational modification of lysine residues has a major influence on protein function. Many mitochondrial proteins are affected by lysine modifications and recent work has described a role for sirtuin enzymes in regulating these processes. This proposal will investigate whether targeted increases in sirtuin activity can improve mitochondrial function and insulin action in mouse models of obesity and insulin resistance.
Investigation Of The Mechanism By Which Medium Chain Fatty Acids Prevent The Development Of Obesity And Insulin Resistance - What Role For GPR84?
Funder
National Health and Medical Research Council
Funding Amount
$512,541.00
Summary
Medium chain fatty acids do not induce the same degree of obesity and insulin resistance as long chain fatty acids and this is due to changes in metabolism in skeletal muscle and adipose tissue. In this proposal we will investigate whether medium chain fatty acids induce their beneficial effects by interacting with a specific G protein-coupled receptor named GPR84. This receptor may be a new therapeutic target for the treatment of metabolic diseases.
Development Of A Specific Activin Antagonist For Therapeutic Applications
Funder
National Health and Medical Research Council
Funding Amount
$504,287.00
Summary
Activin is a key regulator of homeostasis in several organs and tissues, including ovaries, testes, liver and skin, and alterations in activin�s activity can result in fibrosis, cachexia and cancer. In this grant we propose to develop a specific activin antagonist by modifying the activin A propeptide. This novel reagent could be used to promote liver growth in severe hepatic disease and prevent fibrosis in numerous tissues.
Dietary Protein Effects In Elderly Women: Musculoskeletal, Renal, Cardiovascular And Body Composition Endpoints
Funder
National Health and Medical Research Council
Funding Amount
$478,946.00
Summary
Fractures and falls of the elderly are major health problems in our community in terms of disability and cost. It is critical to the future health of our aging population to develop non-pharmaceutical interventions to maintain health into old age. Epidemiologic studies have shown that relatively high protein intake is associated with increased bone mineral mass and reduced incidence of osteoporotic fracture in elderly people. Low protein intakes can lead to loss of muscle mass. To date there hav ....Fractures and falls of the elderly are major health problems in our community in terms of disability and cost. It is critical to the future health of our aging population to develop non-pharmaceutical interventions to maintain health into old age. Epidemiologic studies have shown that relatively high protein intake is associated with increased bone mineral mass and reduced incidence of osteoporotic fracture in elderly people. Low protein intakes can lead to loss of muscle mass. To date there have been no randomised trials of sufficient duration to examine the effects of increased dietary protein intake on bone and muscle health of the elderly. The aim of this study is to examine the effectiveness of protein supplementation for the prevention of osteoporosis and muscle wasting in elderly women, and the safety of such an intervention through monitoring renal function and risk factors for cardiovascular disease. Two hundred and twenty women will be recruited to this study and be assigned to protein group or placebo group. Women in the protein group will received 250 ml high protein drink (containing 30 g protein) per day and women in the placebo group will receive placebo drink containing the same amount of energy, calcium but no additional protein. Bone structure, muscle mass, body composition, renal function and risk factors for cardiovascular disease will be monitored during the 2 year study period. The results of this randomised, controlled study will clarify the role of protein on bone mass and structure, muscle mass and body composition in the elderly. At the same time, the safety of such intervention on renal and cardiovascular endpoints will also be evaluated. It is envisaged that the results of this study if positive will translate into both immediately applicable intervention strategies that are relevant at a program and an individual level.Read moreRead less
Novel Interactions Between GnRH Receptor And E2F4 Transcription Factor.
Funder
National Health and Medical Research Council
Funding Amount
$462,750.00
Summary
The reproductive endocrine system is under the control of gonadotropin-releasing hormone (GnRH), signalling via its G-protein coupled receptor (GPCR) in the anterior pituitary gland. The GnRH receptor (GnRHR) is the drug target for the treatment of a range of endocrine-related disorders as well as hormone-dependent cancers. Sustained treatment with either GnRH agonists or antagonists can block gonadotropin secretion indirectly, via down-regulation of the pituitary receptor resulting in a reducti ....The reproductive endocrine system is under the control of gonadotropin-releasing hormone (GnRH), signalling via its G-protein coupled receptor (GPCR) in the anterior pituitary gland. The GnRH receptor (GnRHR) is the drug target for the treatment of a range of endocrine-related disorders as well as hormone-dependent cancers. Sustained treatment with either GnRH agonists or antagonists can block gonadotropin secretion indirectly, via down-regulation of the pituitary receptor resulting in a reduction of gonadotropin secretion and consequent decline in steroid production. As the majority of tumours treated with GnRH analogues are hormone-dependent, this starves the tumour of the steroid support required for growth. However, the concept of a direct anti-tumour effect of GnRH, independent of the pituitary-gonadal axis, is supported by the in vitro inhibition of both cell growth and DNA synthesis in a number of tumour cell lines. Despite the wide use of GnRH analogues, the molecular basis of the growth inhibitory effects resulting from the activation of this receptor is not fully understood. Unravelling the protein interactions underlying receptor-mediated signalling events will provide valuable information towards understanding of receptor function in vivo. We have identified a novel interaction involving the GnRHR and E2F4, a transcription factor involved in suppression of the transcription of genes involved in cell cycle progression. In addition, over 80% of E2F4 knockout mice are sterile. Owing to the role of the GnRHR in the reproductive pathway we are interested in determining whether the GnRHR-E2F4 interaction has an influence on the development of the hypothalamic-pituitary-gonadal axis, hence affecting reproductive capacity. The interaction identified and studied in this proposal has implications for the treatment of reproductive tumours, such as those of the breast and prostate, and understanding the development of the hypothalamic-pituitary-gonadal axis.Read moreRead less
Factors Regulating The Temporal And Spatial Assembly Of G-protein Coupled Receptor-mediated Arrestin Complexes
Funder
National Health and Medical Research Council
Funding Amount
$472,770.00
Summary
G-protein coupled receptors are proteins that are present at the surface of most cells in the human body. They recognise and bind to specific molecules, such as hormones, the act of which results in a specific signal being transmitted into the cell. This signal alters the function of the cell and so it is critical that it is appropriate, both in type and duration. G-protein coupled receptors and the molecules that activate them provide an essential function within the human body for communicatin ....G-protein coupled receptors are proteins that are present at the surface of most cells in the human body. They recognise and bind to specific molecules, such as hormones, the act of which results in a specific signal being transmitted into the cell. This signal alters the function of the cell and so it is critical that it is appropriate, both in type and duration. G-protein coupled receptors and the molecules that activate them provide an essential function within the human body for communicating between cells, and consequently between organs. They are a major mechanism by which nerve signals are transmitted and hormones regulate bodily functions. They are therefore an important target for pharmaceuticals, with up to 50% of ethical drugs and many drugs of abuse acting upon them. It is critical to understand how these receptors alter cellular function once they receive an appropriate signal, but it is also essential to know how such responses are switched off. Arrestins are proteins within cells that interact with G-protein coupled receptors to 'arrest' their signalling. They desensitise the cell to continuous stimulation, but also act to resensitise the cell to respond to future, separate signals. Recently, they have also been shown to provide alternative mechanisms of altering cellular activity by interacting with other cellular proteins. These interactions greatly increase the potential ways in which a cell can respond once a G-protein coupled receptor is activated. Understanding the resulting complexity is essential if we are to fully exploit the vast therapeutic potential of this important receptor family.Read moreRead less
Effects Of Replacement And Withdrawal Of Testosterone In Human Males On Muscle, Bone And Fat
Funder
National Health and Medical Research Council
Funding Amount
$156,682.00
Summary
Male sex hormone or androgen deficiency (AD) is a common, but under-diagnosed condition. AD decreases well being and contributes to muscle weakness, bone fragility and weight gain. Cutting edge technology will be used to help explain how AD may relate to these negative effects, particularly on muscle function. Given the importance of aging, frailty, osteoporosis and obesity, understanding the role of hormones in these conditions may have major implications for prevention and treatment.