Early Predictors And Body Composition Changes Associated With Adiposity Rebound
Funder
National Health and Medical Research Council
Funding Amount
$201,650.00
Summary
Overweight and obesity rates are increasing in children, and overweight children have higher risk of adult obesity and therefore diseases including heart attack, stroke and diabetes. The preschool years may offer opportunities to divert children from the path to obesity, before poor physical activity and nutritional habits become firmly established. Adiposity rebound is the time in a child's life (usually around 5 to 6 years of age) when body mass index (BMI) begins to increase after a steady de ....Overweight and obesity rates are increasing in children, and overweight children have higher risk of adult obesity and therefore diseases including heart attack, stroke and diabetes. The preschool years may offer opportunities to divert children from the path to obesity, before poor physical activity and nutritional habits become firmly established. Adiposity rebound is the time in a child's life (usually around 5 to 6 years of age) when body mass index (BMI) begins to increase after a steady decline in BMI in the preschool years. Early adiposity rebound is associated with increased BMI in later life. We don't yet know whether the early adiposity rebound causes the higher BMI, or whether it is simply an early sign of an already-established pathway of behavioural and environmental risk. We need a much better understanding of predictors of early adiposity rebound and the changes that occur to determine if age at adiposity rebound is a modifiable risk factor for adult obesity. This study will document the process and timing of adiposity rebound and the changes in percent body fat and lean body mass that occur during that time. We will also determine whether risk and protective factors for early adiposity rebound and overweight at age 6 years are the same or different. We will study over 400 children on whom extensive data have been collected since birth, including period of gestation, birth weight and length. At various stages during their first two years of life, height, weight, feeding patterns and development were recorded. We will measure BMI and perform bioimpedance analysis (BIA) on these children six times between 4 and 6 years of age. BIA provides a measure of body fat and lean mass that is well accepted by children. This will help determine the relationship between changing BMI at different ages and the fat-to-lean mass ratios associated with those changes. This study is the first to consider body composition changes during adiposity rebound.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
Micro-architectural Bone Structure Determined By Magnetic Resonance Imaging (MRI)
Funder
National Health and Medical Research Council
Funding Amount
$52,288.00
Summary
Osteoarthritis is the main form of arthritis. Bone metabolism is involved in osteoarthritis, however it is unknown how this relates to knee structures prior to disease onset. Magnetic Resonance Imaging techniques enable measurement of a healthy knee joint to a diseased one. By using the Geelong Osteoporosis Study, we will demonstrate how bone metabolism affects change in knee structure, and the risk of osteoarthritis.
Effects Of Testosterone And Oestrogen On Body Composition
Funder
National Health and Medical Research Council
Funding Amount
$348,768.00
Summary
Masculinising and feminising hormones such as testosterone and oestrogen respectively are important hormones controlling the amount of muscle, fat and bone in the body. By studying people with conditions such as prostate cancer where these hormone levels are disrupted, we aim to understand how testosterone and oestrogen affects various body systems, which may lead to new treatments for important public health problems of frailty, obesity and heart disease, and osteoporosis.
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
Measuring Changes In Fluids, Fat, Muscle Mass, Proteins & Other Body Components Non-invasively Through Course Of Illness
Funder
National Health and Medical Research Council
Funding Amount
$120,000.00
Summary
The course of non-cancer related disease is difficult to assess clinically making it hard for clinicians to accurately predict the end of life course of illness for patients. No matter what the end of life disease is, death will involve multi-system organ failure and changes in body composition. These changes, including fluid distribution, muscle mass and type and fat mass as well as measures of body mass index, basal metabolic rate and arm muscle circumference can be accurately followed with no ....The course of non-cancer related disease is difficult to assess clinically making it hard for clinicians to accurately predict the end of life course of illness for patients. No matter what the end of life disease is, death will involve multi-system organ failure and changes in body composition. These changes, including fluid distribution, muscle mass and type and fat mass as well as measures of body mass index, basal metabolic rate and arm muscle circumference can be accurately followed with non-invasive multi-frequency bio-impedance. This information will provide a basis to either confirm the clinical diagnosis or lead to recommendations for change.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
The Relationship Of Body Composition, Renal Impairment And Inflammatory Cytokines In Indigenous Persons With Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$119,644.00
Summary
Indigenous Australians bare a disproportionate burden of cardiovascular disease, diabetes and kidney failure. The metabolic syndrome (the combination of obesity, insulin-resistance, abnormal lipids, and hypertension) is a common occurrence and important risk factor for the above chronic conditions in this population. Further study of the relationship of fat distribution, metabolic syndrome, heart disease, diabetes and CKD is of benefit to understand and prevent mortality in this population.