Enhancing The Cardioprotective Effect Of Diadenosine Tetraphosphate: Designing Inhibitors Against Ap4A Hydrolase
Funder
National Health and Medical Research Council
Funding Amount
$442,500.00
Summary
Ischemia describes the condition where blood flow in the blood vessels of the heart is decreased or blocked, preventing delivery of oxygen and nutrients to the heart. Ischemic preconditioning is a phenomenon where short bursts of ischemia, followed by reperfusion, actually protect the heart from a subsequent longer period of ischemia. The biochemical signalling events involved in preconditioning are complex and incompletely defined, but most likely involve multiple pathways, although the mitocho ....Ischemia describes the condition where blood flow in the blood vessels of the heart is decreased or blocked, preventing delivery of oxygen and nutrients to the heart. Ischemic preconditioning is a phenomenon where short bursts of ischemia, followed by reperfusion, actually protect the heart from a subsequent longer period of ischemia. The biochemical signalling events involved in preconditioning are complex and incompletely defined, but most likely involve multiple pathways, although the mitochondrial ATP-dependent potassium channel may be in common with most pathways. Pretreatment with the compound diadenosine tetraphosphate (Ap4A) mimics ischemic preconditioning with noticeable reductions in tissue necrosis (cell death). This treatment has been shown in experimental work to protect the heart during periods of stress such as in heart surgery or recovery from an ischemic event. The biological site of action by Ap4A may be the mitochondria ATP-dependent potassium channel or an associated protein. Ap4A can be degraded by enzymes located inside and on the outside of heart cells, notably by two forms of Ap4A hydrolase. We will use antibody assays to understand the specific localization and amount of Ap4A hydrolase before and after ischemia and after ischemic preconditioning in human heart muscle and blood vessels. We propose to determine the structure of the enzyme and use novel computer methods to screen databases for potential inhibitors. These inhibitors of Ap4A hydrolase activity could aid the design of a potent inhibitor that would prevent Ap4A hydrolase from degrading Ap4A and therefore enhance the cardioprotective properties of Ap4A as well as minimizing side effects from the break down of Ap4A. We will also use these inhibitors and other known non-degradable Ap4A analogues in bioassays to test the relative significance of Ap4A hydrolase present in different cellular locations.Read moreRead less
Novel Vasoactive Pathways In Liver Disease; Experimental And Clinical Studies
Funder
National Health and Medical Research Council
Funding Amount
$535,333.00
Summary
Cirrhosis of the liver due to chronic hepatitis and other common liver diseases is now a major cause of illness and death in Australia. This project will examine how a hormone system called the renin angiotensin system contributes to the development of liver damage in these diseases. We will study whether drugs targeting this system can be used to reduce liver scarring and prevent the development of cirrhosis and its complications.
Salt And Cardiovascular Disease: Does Acute Salt-Sensitivity Convey Greater Cardiovascular Risk?
Funder
National Health and Medical Research Council
Funding Amount
$597,578.00
Summary
Salt intake of Australian adults is 10X more than required. Further, salt intake in very young children is alarmingly high secondary to high consumption of salty snacks and processed food. High dietary salt intake has been associated with increased cardiovascular disease and death. We will examine the cardiovascular risks for adults and children on a high salt diet and examine whether switching to a low salt diet ameliorates the high blood pressure and heart disease caused by high salt diets
Synchrotron X-ray Assessment Of Airway Surface Physiology For Cystic Fibrosis
Funder
National Health and Medical Research Council
Funding Amount
$778,228.00
Summary
We seek a cure or long-lasting therapy for the fatal airway disease in cystic fibrosis. Disease is caused by a shallow and dehydrated airway surface liquid (ASL), allowing bacteria to infect the lung. We can introduce a corrective gene into mouse airways where it can be effective for over 1 yr, but no fast, accurate and non-invasive measurement exists to test if treatments are successful. We will develop methods using synchrotron light to directly measure ASL depth changes in live mouse airways.