Of Mice And Men: Assessing Dietary Proteins Role On Appetite Regulation, Obesity And Cardiovascular Risk
Funder
National Health and Medical Research Council
Funding Amount
$86,521.00
Summary
While the challenge of understanding and managing the global obesity epidemic is well recognised, the role that nutrition plays is more complex than at first glance. Dietary protein may be of central importance in managing weight and small changes in protein consumption may lead to large changes in energy intake and weight. We propose to look at the effects of dietary protein on appetite, its hormonal regulation, and on the risk of developing metabolic diseases such as diabetes.
Targeting Small Heat Shock Proteins In Diseases Associated With Alpha-synuclein Aggregation
Funder
National Health and Medical Research Council
Summary
This research will provide fundamental insight into processes that control the onset and progression of neurological diseases such as Parkinson’s disease, and may lead to the development of novel drugs to treat these disorders. The work will increase Australia's international research standing and provide high-quality multi-disciplinary training to research students.
This proposal is designed to test the protein leverage hypothesis (PLH) in humans: the idea that the level of food consumption in humans, like other animals, is adjusted to maintain a target protein intake. As the prevalence of overweight and obesity increases, with its attendant health problems, the need to identify which dietary components limit rather than exacerbate energy intake is imperative. According to the PLH, the consumption of a diet low in % protein and high in % fat and carbohydrat ....This proposal is designed to test the protein leverage hypothesis (PLH) in humans: the idea that the level of food consumption in humans, like other animals, is adjusted to maintain a target protein intake. As the prevalence of overweight and obesity increases, with its attendant health problems, the need to identify which dietary components limit rather than exacerbate energy intake is imperative. According to the PLH, the consumption of a diet low in % protein and high in % fat and carbohydrate, typical of many Western countries, inevitably requires the ingestion of additional energy to maintain protein intake constant, thus driving weight gain. Conversely, the consumption of a diet that is relatively high in % protein requires the ingestion of lower levels of energy, creating the potential for weight loss. Preliminary experimental and population-level nutritional survey data support the PLH, as does the finding that protein is more satiating than other macronutrients. If, as predicted, small changes in the proportion of protein in diets described in the current study are found to impact on total energy intake there will be significant implications for weight control strategies. Thus, if the PLH is confirmed, public health dietary recommendations and government policy settings for the food industry will need to change. Large-scale intervention studies aimed at demonstrating the longer term impact on body weight will also be required.Read moreRead less
The Metabolic Effects Of Oestrogens And SERMs: Regulatory Interactions With The GH-IGF-system In Health And Disease
Funder
National Health and Medical Research Council
Funding Amount
$379,142.00
Summary
This project extends work aimed at understanding how GH and sex hormones work together to optimise physical health in women and men. It addresses the benefits and safety of oestrogen compounds in relation to their effects on body fat and muscle (body composition). Oestrogen compounds are among the most widely used medicines and include tradition oestrogens (female hormone) and synthetic oestrogens called SERMs. Oestrogens are used in young women as oral contraception and in the postmenopause for ....This project extends work aimed at understanding how GH and sex hormones work together to optimise physical health in women and men. It addresses the benefits and safety of oestrogen compounds in relation to their effects on body fat and muscle (body composition). Oestrogen compounds are among the most widely used medicines and include tradition oestrogens (female hormone) and synthetic oestrogens called SERMs. Oestrogens are used in young women as oral contraception and in the postmenopause for replacement therapy. Body composition is an important determinant of fitness and health. Obesity reduces fitness and increases the risk of diabetes and heart attacks while muscle loss causes weakness and frailty. GH is a major regulator of body composition; it acts by breaking down fat and building muscle mass. We discovered that oestrogens, when taken as a tablet interferes with the action of GH and causes detrimental changes in body composition. On the positive side, we have exploited the GH blocking action to treat acromegaly. This is a debilitating disease of excessive GH production from a pituitary tumour and for which available drug treatments are very expensive and require injection. The effects of SERMs on body composition are unknown. SERMs are interesting compounds because they act like oestrogens in some but as oestrogen blockers in other tissues. These are widely used in the treatment of breast cancer and osteoporosis. The extent to which they interfere with the action of GH has not been studied. They may exert additional effects because they act on the pituitary gland to reduce the secretion of GH. They may also prove to be effective in acromegaly which could extend their usefulness to men. In summary, the work will provide important information on the long-term benefits of SERMs in patient groups that tend to be frail. It may also prove to be a simple and inexpensive treatment for acromegaly.Read moreRead less
Improving Weight Loss Outcomes By Minimizing Adaptive Responses To Energy Restriction
Funder
National Health and Medical Research Council
Funding Amount
$621,458.00
Summary
While losing excess weight reduces the risk of lifestyle diseases such as diabetes, current weight loss strategies are ineffective for most, in part because the body mounts a ‘famine reaction’ that increases hunger, decreases metabolic rate and may also cause loss of muscle and bone mass. This research aims to determine the effects of the famine reaction on body composition, as well as to identify new ways to block the famine reaction with food, thereby enabling more people to attain and maintai ....While losing excess weight reduces the risk of lifestyle diseases such as diabetes, current weight loss strategies are ineffective for most, in part because the body mounts a ‘famine reaction’ that increases hunger, decreases metabolic rate and may also cause loss of muscle and bone mass. This research aims to determine the effects of the famine reaction on body composition, as well as to identify new ways to block the famine reaction with food, thereby enabling more people to attain and maintain a healthy body weight and composition.Read moreRead less
Regulation Of Growth Hormone Action By Sex Steroids: Metabolic Implications For Health And Disease
Funder
National Health and Medical Research Council
Funding Amount
$353,250.00
Summary
Fitness and health is determined by body composition, the amount of fat and lean tissue in the body. Obesity increases the risk of diabetes, blood pressure and heart attacks, while muscle wasting reduces strength and fitness. Body composition is controlled by hormones such as growth hormone (GH) which reduces body fat by stimulating its metabolism (burning) and increases lean tissue by stimulating protein synthesis. These metabolic actions of GH are exerted through the liver. This proposal seeks ....Fitness and health is determined by body composition, the amount of fat and lean tissue in the body. Obesity increases the risk of diabetes, blood pressure and heart attacks, while muscle wasting reduces strength and fitness. Body composition is controlled by hormones such as growth hormone (GH) which reduces body fat by stimulating its metabolism (burning) and increases lean tissue by stimulating protein synthesis. These metabolic actions of GH are exerted through the liver. This proposal seeks to understand how sex hormones control the amount of body fat and muscle in women and men. Based on previous research in our laboratory, we propose that sex hormones control the action of growth hormone on the liver. We will test the hypothesis that oestrogens impair the ability of the liver to burn fat and build protein in response to GH while male hormones have the opposite effect. The effect of oestrogen occurs only when oestrogen is taken as a tablet because the liver is exposed to high concentrations of this hormone after gut absorption. It causes postmenopausal women to gain fat and lose muscle. Apart from oestrogens, there are many other compounds with oestrogen-like activities such as phytooestrogens (oestrogens found in plants) and SERMs (used for treating osteoporosis). Their effect on the liver and body composition are unknown but important because of their widespread use in the community. The significance of these studies relate to optimising the benefits of oestrogen compounds by defining their metabolic effects on the liver. In men, understanding how male hormones work as anabolic agents may lead to ways of treating protein muscle wasting.Read moreRead less
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