Examination Of The Molecular Pharmacology Of Anthracyclines Induced Via Their Interaction With Iron
Funder
National Health and Medical Research Council
Funding Amount
$618,401.00
Summary
Anthracyclines are highly effective anti-cancer drugs, but their use is limited by toxic effects on the heart. This is thought to be due to these drugs directly binding iron (Fe). Indeed, we showed that anthracyclines induced marked changes in the way heart cells utilise Fe (DR1-3, 38; Mol. Pharmacol. 2002, 2003, 2004, 2005). We were the first to show that anthracyclines prevent Fe release from the criticial Fe storage protein ferritin. This prevents the use of Fe for vital processes eg. DNA and ....Anthracyclines are highly effective anti-cancer drugs, but their use is limited by toxic effects on the heart. This is thought to be due to these drugs directly binding iron (Fe). Indeed, we showed that anthracyclines induced marked changes in the way heart cells utilise Fe (DR1-3, 38; Mol. Pharmacol. 2002, 2003, 2004, 2005). We were the first to show that anthracyclines prevent Fe release from the criticial Fe storage protein ferritin. This prevents the use of Fe for vital processes eg. DNA and haem synthesis. Hence, this effect probably contributes to the cytotoxic activity of anthracyclines on the heart. We showed that novel drugs developed in my lab that bind Fe called chelators show high activity in animals (DR4) and prevent anthracycline-mediated Fe accumulation in ferritin. Importantly, Fe chelators have been shown to inhibit anthracycline-mediated cardiotoxicity. Indeed, the clinically used cardioprotective agent, ICRF-187, is actually an Fe chelator (5, DR6). However, ICRF-187 is not totally successful in terms of its cardioprotective effects and can cause myelosuppression (5, DR6). While the clinically used chelator, desferrioxamine (DFO), can prevent anthracycline-mediated cardiotoxicity, its poor membrane permeability limits its effectiveness. Our chelators are highly permeable and overcome the disadvantages of DFO (DR4). Thus, they are vital to examine for preventing anthracycline-mediated cardiotoxicity. In this proposal we will examine the changes in Fe metabolism induced by anthracyclines and test the hypothesis that novel Fe chelators may prevent the cardiotoxicity of these agents. We also aim to be the first to assess if preparation of anthracyclines which cannot bind iron prevents their cardiotoxicity. This will be done by preparing metal complexes of these drugs which prevent Fe-binding eg. anthracycline-zinc complexes. These studies are important for the development of less cardiotoxic forms of these very useful anti-tumour agents.Read moreRead less
Understanding The Acute And Cumulative Metabolic Effects Of Prolonged Sitting In Adults
Funder
National Health and Medical Research Council
Funding Amount
$416,597.00
Summary
Sedentary behaviour (sitting time) has been linked to an increased risk of chronic illnesses, including type 2 diabetes and obesity, but recent evidence suggests that light-intensity activity (non-exercise activities of daily living) is associated with reduced risk. These studies will examine whether breaking up sitting time with frequent short periods of activity can overcome the negative effects of prolonged sitting on blood glucose and blood fats in overweight older adults.
Non-HFE Haemochromatosis In Australia: Natural History And Molecular Characterisation
Funder
National Health and Medical Research Council
Funding Amount
$179,948.00
Summary
Hereditary haemochromatosis (HH) is a disorder characterised by excessive iron absorption and build up of iron in body organs such as the liver. The excess iron can be toxic and cause disease. Most HH is caused by mutations in the HFE gene. Other forms are caused by mutations in other genes. This project will characterise a new form of HH that is unrelated to any of the previously known genes. The project aims to find the gene for this new condition by genetic analysis in a large family.
EXAMINING THE RELATIONSHIP BETWEEN MATRIPTASE-2 AND HEMOJUVELIN, TWO ESSENTIAL REGULATORS OF IRON HOMEOSTASIS
Funder
National Health and Medical Research Council
Funding Amount
$533,541.00
Summary
The control of iron levels is important in health and well being. Too little can lead to iron deficiency and anaemia, conversly too much can lead to haemochromatosis and tissue damage. We will examine the role of two proteins, matriptase-2 and hemojuvelin that when mutated cause iron deficiency or iron overload respectively. We will study how these proteins interact and work in opposite directions to control iron levels. The results will help to develop new therapeutics for iron disorders.
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.