How Commonly Used Psychoactive Drugs Affect The Hypothalamo-pituitary-adrenal Axis
Funder
National Health and Medical Research Council
Funding Amount
$411,448.00
Summary
The body makes a number of responses when it is subjected to stress, and these include the secretion of hormones from the adrenal gland, including cortisol. It is not surprising that cortisol has effects upon the way the brain operates, nor is it surprising that diseases that are associated with stress (e.g. depression, alcoholism and other psychiatric complaints) create abnormal cortisol secretion. The drugs that are known to be successful in treating conditions such as depression and anxiety h ....The body makes a number of responses when it is subjected to stress, and these include the secretion of hormones from the adrenal gland, including cortisol. It is not surprising that cortisol has effects upon the way the brain operates, nor is it surprising that diseases that are associated with stress (e.g. depression, alcoholism and other psychiatric complaints) create abnormal cortisol secretion. The drugs that are known to be successful in treating conditions such as depression and anxiety have been shown to affect the secretion of cortisol, but, somewhat paradoxically, we do not precisely know how they operate. The aim of this research is to examine how drugs that are commonly used for the treatment of a number of psychiatric conditions (e.g. Prozac, Tofranil, Xanax, morphine and naltrexone) affect the secretion of hormones from the brain that ulitmately regulate the secretion of cortisol. We propose that the effects of these drugs is related to how they operate, and for how long they have been given. The findings generated by this research may help us determine new ways of diagnosing and treating a range of conditions.Read moreRead less
Molecular Regulation Of Metabolism And Body Composition By Ski Via Crosstalk With Nuclear Hormone Receptor Signalling.
Funder
National Health and Medical Research Council
Funding Amount
$558,441.00
Summary
Obesity is a common and burdensome health problem in the community which leads to diabetes and heart disease. A number of factors, including hormones play important roles in determing risk of obesity. This study proposes to investigate whether the Ski gene which is a regulatory factor for many hormones affects metabolism in transgenic mouse models of altered Ski function. The proposed studies may identify Ski as a target for therapy for obesity and improvement in sketal muscle metabolism.
Osteoblast Control Of Mesenchymal Progenitor Cell Differentiation: The Role Of Glucocorticoids And Wnt Signalling.
Funder
National Health and Medical Research Council
Funding Amount
$443,131.00
Summary
Osteoporosis is an important and growing health issue. Reduced ability to make new bone is an important cause of osteoporosis. In this project we will study how the immature cells which eventually make bone are recruited and controlled. In particular, we will study how genes coding for important growth factors are regulated so that the proper signals are sent to young cells to induce them to become bone-making rather than fat-making cells.
Glucocorticoid-progesterone Interactions In The Control Of Fetal And Placental Growth
Funder
National Health and Medical Research Council
Funding Amount
$227,036.00
Summary
The growth and function of the placenta is of critical importance to the successful maintenance and completion of human pregnancy. The placenta is effectively the lifeline of the growing fetus through its supply of nutrients, removal of wastes, and coordination of homone signals that regulate fetal growth and development. If the placenta does not perform these functions adequately, the growth rate of the fetus is compromised and can lead to difficulties before and after birth. This project exami ....The growth and function of the placenta is of critical importance to the successful maintenance and completion of human pregnancy. The placenta is effectively the lifeline of the growing fetus through its supply of nutrients, removal of wastes, and coordination of homone signals that regulate fetal growth and development. If the placenta does not perform these functions adequately, the growth rate of the fetus is compromised and can lead to difficulties before and after birth. This project examines how two important steroid hormones, progesterone and glucocorticoids, interact with growth factors in the placenta to control its growth and function. Progesterone is recognized as 'the hormone of pregnancy' as it helps the mother adapt to pregnancy. Progesterone may also affect the placenta by regulating its synthesis and breakdown of other hormones, and the balance between placental cell proliferation and death. These effects of progesterone will be studied in this project. We will also examine how glucocorticoid hormones regulate the growth and function of the placenta. Glucocorticoids are structurally very similar to progesterone, and are secreted by the adrenal gland in increased quantities during pregnancy. Glucocorticoids exert a wide range of effects on the mother, placenta and fetus; indeed, glucocorticoids are recognized clinically as the single-most importnat signal for fetal maturation in late pregnancy. However, too much glucocorticoid retards fetal and placental growth, and in this project we will study how this occurs in the placenta, and how the placenta may protect itself from detrimental effects of glucocorticoids. We will test whether placental growth is restricted by glucocorticoids through their effects on placental growth factor hormones. Overall, these studies could have important implications for the clinical management of pregnancy, particularly in relation to fetal and placental growth.Read moreRead less
Interactions Between Fetal Programming And Postnatal Diet In Development Of The Metabolic Syndrome
Funder
National Health and Medical Research Council
Funding Amount
$445,578.00
Summary
More than 50,000 Australians die annually from cardiovascular disease, accounting for almost 40% of all deaths. Obesity and high blood pressure are both key risk factors for cardiovascular disease, and so it is crucial that we understand the underlying causes of these conditions and how lifestyle changes, such as diet, can prevent them. We now know that several adult-onset diseases, including high blood pressure, obesity and diabetes, are influenced by how well we grow and develop as a fetus. Th ....More than 50,000 Australians die annually from cardiovascular disease, accounting for almost 40% of all deaths. Obesity and high blood pressure are both key risk factors for cardiovascular disease, and so it is crucial that we understand the underlying causes of these conditions and how lifestyle changes, such as diet, can prevent them. We now know that several adult-onset diseases, including high blood pressure, obesity and diabetes, are influenced by how well we grow and develop as a fetus. This effect, known as 'fetal programming', means that if we have a poor environment as a fetus (eg, maternal undernutrition), we are more likely to develop health problems such as high blood pressure many years later. In this study we are interested in how the events in fetal life 'program' these later health problems, and how we might reverse the adverse effects by lifestyle changes after birth. We have developed an animal model in which high blood pressure and problems with fat and muscle function that can lead to obesity and diabetes. These detrimental effects on adult health can be completely prevented in our model by placing offspring on a diet rich in omega-3 fats from the time of birth. These fats are commonly found in fish oil and are well known for their beneficial effects on cardiovascular function. The present proposal will extend these findings by determining whether omega-3 fatty acids can reverse the adverse programming outcomes after they have emerged in adult life. We will also investigate whether fetal programming effects are made even worse by the consumption of excess total dietary fat during development to adulthood, and if this effect can also be overcome by supplementation of the diet with omega-3 fats.Read moreRead less