Molecular Attributes And Physiological Significance Of Beta1L-adrenoceptors
Funder
National Health and Medical Research Council
Funding Amount
$754,353.00
Summary
Beta-blockers are used for the management of cardiovascular diseases including heart failure. We have discovered that one group of beta-blockers not only blocks the receptor but stimulates it. To explain this we hypothesize that human beta-adrenoceptors exist in two different 'states' , high and low. We are now determining whether 1. the low state causes progression of heart failure, 2. the molecular basis of the two states and 3. we can make new compounds to block the low state.
Studies Of Metabolites Of Synthetic Flavonols For The Treatment Of Cardiovascular Disease
Funder
National Health and Medical Research Council
Funding Amount
$207,440.00
Summary
Cardiovascular disease, including heart attack and stroke, is the leading killer of Australians. A promising new drug, NP202, can reduce the amount of tissue damaged from a heart attack; however, its mechanism of action remains obscure. NP202 is metabolized to a range of compounds, one of which is partly responsible for its beneficial effects. In this project we will identify other metabolites of NP202 and characterize their biological activity to gain insight into its mechanism of action.
Cytochrome P450 CYP3A Regulation In Humanized Transgenic Mice
Funder
National Health and Medical Research Council
Funding Amount
$376,980.00
Summary
The study of the regulation of human genes is inherently difficult. It is difficult or impossible to gain access to many body tissues in either healthy or sick individuals to examine coordinated gene function (or dysfunction). For this reason, it is often the case that we have a much better understanding of gene function in species such as rats and mice, the most common animal environments for biomedical research. However, findings in animals often fail to meaningfully mirror what occurs in man. ....The study of the regulation of human genes is inherently difficult. It is difficult or impossible to gain access to many body tissues in either healthy or sick individuals to examine coordinated gene function (or dysfunction). For this reason, it is often the case that we have a much better understanding of gene function in species such as rats and mice, the most common animal environments for biomedical research. However, findings in animals often fail to meaningfully mirror what occurs in man. To progress our understanding of human genes we need to develop models that more faithfully reproduce the human situation in an environment that is amenable to both manipulation and close examination, such as the novel 'humanised' mouse models described in this application. This application deals with the regulation genes that control liver enzymes belonging to the human cytochrome P450 3A (CYP3A) subfamily. These enzymes are present in several tissues including liver, gut, lung and breast. They form the main disposal pathway for foreign chemicals such as drugs, environmental pollutants and some cancer causing chemicals. In addition they are involved in the breakdown of several important internally produced substances, such as steroid hormones. Altered formation of CYP3A enzymes can have a dramatic impact on the action of many important drugs and may predispose to some forms of cancer. In this project, we will insert the genes for all four human CYP3A enzymes into mice. We expect that these 'humanised' mouse models will effectively enable the human situation to be studied in a convenient animal model and allow detailed studies to be performed. A knowledge of the mechanisms involved in CYP3A enzyme formation is of particular importance to the fields of drug and steroid metabolism (both in health and in disease states), liver diseases and foetal pharmacology. In addition, these models will provide a new and useful tool for drug development.Read moreRead less
NOVEL CGMP-BASED THERAPIES PREVENT LEFT VENTRICULAR REMODELLING
Funder
National Health and Medical Research Council
Funding Amount
$533,433.00
Summary
Over 300,000 Australians are affected by heart failure. Current drugs for cardiac remodelling (the decline in heart pumping function and changed structure that precede heart failure) slow but not reverse disease progression. We have identified a new, nitrovasodilator-based therapy superior to those currently available. We propose it represents a more effective treatment for reversing abnormalities in both structure and function in the remodelled heart, preventing or delaying heart failure.
Novel Aspects Of Angiotensin AT1 Receptor Signalling Pathways
Funder
National Health and Medical Research Council
Funding Amount
$219,750.00
Summary
Hormones are chemicals released into the blood to influence tissue function by binding to specific sites (receptors) located on the cells found in a particular tissue. In general, it has been considered that a specific receptor activates a specific response when bound by the hormone. However, it is now clear that closely related hormones can activate different patterns of response even when they bind the one type of receptor. The full consequence of this phenomenon is still unknown. Its signific ....Hormones are chemicals released into the blood to influence tissue function by binding to specific sites (receptors) located on the cells found in a particular tissue. In general, it has been considered that a specific receptor activates a specific response when bound by the hormone. However, it is now clear that closely related hormones can activate different patterns of response even when they bind the one type of receptor. The full consequence of this phenomenon is still unknown. Its significance will be investigated in this project for important hormones which are involved in blood pressure control. The renin-angiotensin system makes the hormone angiotensin II which increases blood pressure through actions the heart, blood vessels, nerves and kidneys. One particular receptor type, the AT1 receptor, is responsible for the majority of effects of angiotensin II on these tissues and drugs that inhibit the activity of this receptor are very useful therapies for diseases such as hypertension and heart failure. However, Angiotensin III is a second hormone of the renin-angiotensin system that may also have important effects on tissue function when it activates the AT1 receptor. We have evidence that the type of tissue response that results from angiotensin III activated AT1 receptors is different from the response that results from angiotensin II activation of the same receptors. This raises the possibility that the effects of the AT1 receptor in cardiovascular disease might be differentially promoted by the two angiotensins. This project will investigate the mechanisms by which angiotensin II and anagiotensin III can elicit different activation via the AT1 receptor, and will determine the consequences of this differntial activation to tissue function.Read moreRead less
TARGETING ROS-INDUCED DAMAGE RESCUES THE DIABETIC HEART
Funder
National Health and Medical Research Council
Funding Amount
$487,669.00
Summary
Over 1 million Australians have diabetes. Many of these patients die from cardiovascular disease. We have identified free radicals as a major cause of decreased pumping function and impaired recovery from each heartbeat in the diabetic heart. Stronger antioxidant approaches and-or activation of protective protein pathways is a more effective treatment for reversing impaired function in the diabetic heart, preventing or delaying heart failure in patients with diabetes.
NADPH Oxidase In Pathological Angiogenesis In Solid Tumours And Retina
Funder
National Health and Medical Research Council
Funding Amount
$581,989.00
Summary
Understanding blood vessel growth has profound clinical implications for many diseases. Blocking vessel growth is a promising strategy for treatment of cancer and eye complications accompanying diabetes, whereas treatments to stimulate new vessel growth will treat ischemic disorders ie. heart attack and stroke. Here we investigate whether targeting an enzyme that grows blood vessels has potential for making drugs to stop tumor growth or eye damage that occurs with diabetes and premature births.