Understanding The Opposing Roles Of SWI-SNF In The Control Of Gene Programs For Pathological Cardiac Hypertrophy
Funder
National Health and Medical Research Council
Funding Amount
$476,258.00
Summary
Following the success in decoding human genome, i.e. DNA sequence, a major task is to understand how the activity of genes with consequent changes in respective proteins. As proteins are an important component for cell structure and function, such changes in quantity and quality of proteins will play a pivotal role to affect disease development and progression.
Inositol Polyphosphate 1-phosphatase, A Novel Anti-hypertrophic Factor
Funder
National Health and Medical Research Council
Funding Amount
$399,750.00
Summary
Growth of the heart muscle cells occurs after heart attack and in people with high blood pressure or who suffer from diseases such as diabetes. Such growth leads eventually to the development of heart failure, a major cause of death and disability in western societies. We have identified a novel inhibitor of this growth, an enzyme that destroys a signalling intermediate called inositol(1,4)bisphosphate (or IP2). We now need to define how reduction in IP2 reduces growth and whether it provides a ....Growth of the heart muscle cells occurs after heart attack and in people with high blood pressure or who suffer from diseases such as diabetes. Such growth leads eventually to the development of heart failure, a major cause of death and disability in western societies. We have identified a novel inhibitor of this growth, an enzyme that destroys a signalling intermediate called inositol(1,4)bisphosphate (or IP2). We now need to define how reduction in IP2 reduces growth and whether it provides a useful target for therapy.Read moreRead less
I am a cardiac pharmacologist investigating new therapies for the precursors of, and preventing their transition to, heart failure. My core activities focus on factors that control cardiac hypertrophy and ventricular function, in both the absence and pres
Transcriptional Regulatory Complexes Associated With Cardiac Hypertrophy
Funder
National Health and Medical Research Council
Funding Amount
$474,517.00
Summary
Following the success in decoding human genome, i.e. DNA sequence, a major task is to understand how the activity of genes with consequent changes in respective proteins. As proteins are an important component for cell structure and function, such changes in quantity and quality of proteins will play a pivotal role to affect disease development and progression. It has been well known that a group of genes are altered (up or down) in the heart under conditions such as heart muscle overgrowth (ie ....Following the success in decoding human genome, i.e. DNA sequence, a major task is to understand how the activity of genes with consequent changes in respective proteins. As proteins are an important component for cell structure and function, such changes in quantity and quality of proteins will play a pivotal role to affect disease development and progression. It has been well known that a group of genes are altered (up or down) in the heart under conditions such as heart muscle overgrowth (ie hypertrophy), aging or of abnormal beating function. The reasons for such altered gene activity remain poorly understood. Although recent studies from research on genetics or cancer have revealed the important role of the DNA and DNA-bound proteins (called histone) in the control of gene activity, this has rarely been studied in the heart. In this project, we will test our hypothesis that DNA-histone structure is a key factor that control gene activities in ageing and diseased heart. This proposal is supported by our recent findings showing that in the hypertrophied heart, such DNA-histone structure did alter in such a way that fits well with alterations in gene activity. We have planned a series of studies to test this hypothesis in a systematic fashion. A number of sophisticated and cutting-edge techniques and experimental models of heart hypertrophy will be used. We will analyse changes in activities of a number of selected genes in the heart and also analyse changes in DNA-histone structures and chemical modifications at particular regions. These changes will then be linked together. We will also explore the possibility of modulating DNA-histone structure, thereby controlling the degree of cardiac hypertrophy. This project is the joint efforts of scientists with substantial experience in research on gene activity and heart diseases, and is highly likely to generate novel information to and hold significant therapeutic potential.Read moreRead less
Roles Of Interleukins, Chemokines And Circulating Cells In Cardiac Fibrosis
Funder
National Health and Medical Research Council
Funding Amount
$434,134.00
Summary
Cardiac fibrosis is a disease of the heart in which large amounts of collagen are deposited within the heart tissue. This leads to poor heart function and may also lead to sudden death due to arrhythmias (abnormal electrical pulses). This study sets out to define the role of substances called interleukins and special circulating cells called lymphocytes, macrophages and progenitor cells in the development of cardiac fibrosis.
Heart muscle cells have little potential for regeneration, and after a heart attack or in response to chronic hypertension, they grow bigger, resulting in deterioration of function and heart failure. We have compelling evidence that the c-kit protein limits heart regeneration and function. We expect to demonstrate that c-kit inactivation can greatly improve heart regeneration and function after cardiac injury/stress. Our work will have major clinical significance for future heart failure treatme ....Heart muscle cells have little potential for regeneration, and after a heart attack or in response to chronic hypertension, they grow bigger, resulting in deterioration of function and heart failure. We have compelling evidence that the c-kit protein limits heart regeneration and function. We expect to demonstrate that c-kit inactivation can greatly improve heart regeneration and function after cardiac injury/stress. Our work will have major clinical significance for future heart failure treatment strategies.Read moreRead less
Linking Early Heart Growth Stress And Adult Cardiopathology: A New Role For Autophagy
Funder
National Health and Medical Research Council
Funding Amount
$524,013.00
Summary
An enlarged heart at maturity is a major risk factor. The goal of this project is to understand how cardiac growth abnormality in the neonate contributes to adult growth pathology. We have recently discovered that a type of stress-triggered cell death (autophagy) is increased in rodent neonatal hearts which later become enlarged, and that this cell death is regulated by the hormone angiotensin II. We will study the mechanisms involved to identify intervention opportunities to normalize growth.
Anti-apoptotic, Anti-fibrotic, And Positive Inotropic Effects Of Ghrelin And GHRP On Rat And Mouse Cardiac Myocytes
Funder
National Health and Medical Research Council
Funding Amount
$442,530.00
Summary
Growth hormone (GH) is a protein hormone secreted from an endocrine organ, the pituitary gland, below the brain. Synthetic GH-releasing peptides (GHRPs) and endogenous GHRP (ghrelin) possess many other physiological functions in addition to the release of GH. GHRPs have been shown to affect cardiac function in animals and humans through their specific receptors. We recently demonstrated at single cell level that GHRPs increased contraction of cardiac muscle cells and protected them from the prog ....Growth hormone (GH) is a protein hormone secreted from an endocrine organ, the pituitary gland, below the brain. Synthetic GH-releasing peptides (GHRPs) and endogenous GHRP (ghrelin) possess many other physiological functions in addition to the release of GH. GHRPs have been shown to affect cardiac function in animals and humans through their specific receptors. We recently demonstrated at single cell level that GHRPs increased contraction of cardiac muscle cells and protected them from the programmed cell death which occurs in heart failure and myocardial infarction. We also demonstrated that GHRPs protected the heart in chronic heart failure and alleviated functional loss of the heart in experimental heart failure models. Preliminary results now indicate that GHRPs prevent cardiac fibrosis, which accounts for cardiac dysfunction after heart failure and infarction. It is proposed in this project to clarify the mechanism underlying the action of GHRPs in (1) cardiac functional enhancing; (2) anti-cell death; (3) anti-fibrosis effects, in primary cultured rat myocytes in vitro and in cardiac diseased mouse models in vivo. By completing this project, we will be able to (1) better understand the physiological role of ghrelin in the regulation of cardiac function; and (2) clarify the potential for therapeutic use of GHRPs in the treatment of chronic heart failure, a disease affecting 1-2% of the population of Australia, with 5 year mortality rates about 65%.Read moreRead less