The insulin-like growth factor system is involved in promoting cancer growth and survival against treatment with chemotherapy. Insulin-like growth factors-I and -II act via cell surface receptors (IGF-1R). Much effort has been applied to blocking the action of insulin-like growth factors via IGF-1R. However, recently a second mechanism has been identified by which the insulin-like growth factors are involved in cancer. Insulin-like growth factor-II can also promote cancer growth and survival via ....The insulin-like growth factor system is involved in promoting cancer growth and survival against treatment with chemotherapy. Insulin-like growth factors-I and -II act via cell surface receptors (IGF-1R). Much effort has been applied to blocking the action of insulin-like growth factors via IGF-1R. However, recently a second mechanism has been identified by which the insulin-like growth factors are involved in cancer. Insulin-like growth factor-II can also promote cancer growth and survival via an alternative form of the insulin receptor. We will join with our international collaborator to bring together a team of biochemists and protein structural biologists who are world leaders in understanding protein interactions in the insulin and insulin-like growth factor systems. As relatively little is known about this alternate pathway we propose to define the mechanism of binding of insulin-like growth factor-II to the alternate insulin receptor isoform. Using a combination of well-established and novel techniques we will map the interaction. This knowledge will allow design of specific inhibitors to block the action of insulin-like growth factor-II in promotion of cancer cell growth and survival without disruption of the metabolic actions of the insulin receptor.Read moreRead less
Orexins As Neuroendocrine Integrators Between Nutrition And Reproduction Control Systems
Funder
National Health and Medical Research Council
Funding Amount
$332,036.00
Summary
Studies on humans and a range of animal species have shown that the effects of nutrition on reproduction are mediated at least partly by changes in the secretion of gonadotrophin releasing hormone (GnRH) and thus gonadotrophins. A number of metabolic signals must also be involved but those tested to date (glucose, insulin, leptin) do not seem to play major roles. Two exciting new candidates are orexin-A and orexin-B, a recently discovered pair of peptides that stimulate feeding behaviour. They a ....Studies on humans and a range of animal species have shown that the effects of nutrition on reproduction are mediated at least partly by changes in the secretion of gonadotrophin releasing hormone (GnRH) and thus gonadotrophins. A number of metabolic signals must also be involved but those tested to date (glucose, insulin, leptin) do not seem to play major roles. Two exciting new candidates are orexin-A and orexin-B, a recently discovered pair of peptides that stimulate feeding behaviour. They are synthesized in the brain and, in rodents, they either stimulate or inhibit gonadotrophin secretion, depending on the presence of sex steroids. In this project, we will investigate the roles of the orexins as integrators of signals about gonadal activity, nutrition and body condition, all of which affect the activity of the reproductive control centres in the brain. We will use the mature male sheep because it shows clear and repeatable reproductive responses to changes in nutrition. We will locate the orexin-producing cells and the cells that respond to the orexins, and show how orexin production is affected by diet. We will also study the ways in which the orexins affect, and are affected by, the hormone systems that control reproduction and metabolism. Finally, we will try to find out why there are two orexins by looking at how their actions differ. Ultimately, the orexin system might explain the brain processes that are behind many of the reproductive problems that are associated with metabolic disorders, such as appetite loss, excessive exercise, undernutrition, polycystic ovarian syndrome, and insulin-dependent diabetes.Read moreRead less
Respiratory Modulation Of RVLM Premotor Neurons: Role In The Sympathetic Over-activity Of Hypertension.
Funder
National Health and Medical Research Council
Funding Amount
$338,605.00
Summary
Hypertension is a common health disorder in all societies and is a major risk factor for the development of life threatening cardiovascular diseases, including heart failure and stroke. Whilst some effective therapies are available, many patients are not adequately treated or have reduced quality of life due to serious side effects. There is a great need for alternative therapies. The central nervous system is clearly involved in hypertension although the level of that involvement is not well un ....Hypertension is a common health disorder in all societies and is a major risk factor for the development of life threatening cardiovascular diseases, including heart failure and stroke. Whilst some effective therapies are available, many patients are not adequately treated or have reduced quality of life due to serious side effects. There is a great need for alternative therapies. The central nervous system is clearly involved in hypertension although the level of that involvement is not well understood- i.e. is it a causal factor or just a contributor to the maintenance of established hypertension? The experiments outlined in this application are based on the observation that modulation of nervous activity to blood vessels is more influenced by the respiratory system in people with high blood pressure, than in normotensive people. We aim to test whether this increased respiratory modulation might be involved in the generation of the high blood pressure.Read moreRead less
Dengue is the leading mosquito-borne virus causing morbidity and mortality in the tropics. North Queens land has a history of dengue outbreaks, with 5 outbreaks in the last 3 years. Queensland Health has developed a Dengue Fever Management Plan for north Queensland that has had considerable success in preventing small outbreaks of dengue from developing into large epidemics. The cornerstone of this plan is the application of residual insecticide inside premises near dengue cases to kill the mosq ....Dengue is the leading mosquito-borne virus causing morbidity and mortality in the tropics. North Queens land has a history of dengue outbreaks, with 5 outbreaks in the last 3 years. Queensland Health has developed a Dengue Fever Management Plan for north Queensland that has had considerable success in preventing small outbreaks of dengue from developing into large epidemics. The cornerstone of this plan is the application of residual insecticide inside premises near dengue cases to kill the mosquito vector, Aedes aegypti, before it can spread the virus. While this method is effective, it is labor intensive, requires the cooperation of homeowners who may find it intrusive and exposes nontarget insects and animals to insecticide. We propose to develop a lure and kill strategy to improve the efficacy of vector control while minimising the exposure of nontarget animals. Several chemicals have been identified as highly attractive to dengue mosquitoes. Among these are extracts from water infusions of grass that are highly attractive to egg-laying mosquitoes and emanations from human skin that attract host-seeking mosquitoes. We will develop traps incorporating a. mosquito attractants and b. a killing agent to selectively control Ae. aegypti mosquitoes. These will be collectively called lethal traps. This project will employ the following approach towards the development of a lure and kill strtaegy for dengue control a. determine which compounds are most attractive to north Queensland Ae. aegypti in a laboratory wind tunnel; b. confirm the attraction of these compounds using sticky traps in the field; c. conduct field trials of candidate lethal traps to determine the spacing and density of traps needed to control mosquitoes d. conduct a large field trial to examine the efficacy of the optimised lure and kill strategy. We will also conduct ecological studies on aging and the flight range of Ae. aegypti to enhance the development of the strategy.Read moreRead less