Antioxidant Glutathione Peroxidase (GPx) Mimetics And Atherosclerosis: A Role For Targeted Antioxidant Therapy.
Funder
National Health and Medical Research Council
Funding Amount
$358,319.00
Summary
This proposal investigates the use of antioxidant therapy, targeted at increasing the function of the body's important antioxidant enzyme GPx1, to reduce atherosclerosis both in a non-diabetic and diabetic setting. Strong clinical evidence and our recently published data support an important role for GPx1 in limiting atherosclerosis. We will now investigate the molecular mechanisms involved in mediating these effects and whether compounds that mimic GPx1 function reduce atherosclerosis.
Vascular And Neuro-glial Dysfunction In Diabetic Retinopathy
Funder
National Health and Medical Research Council
Funding Amount
$481,500.00
Summary
The retina is responsible for sight. Vision occurs by interactions between blood vessels, neurons (cells that transmit electrical signals for vision) and glia (cells that support the retina). In diabetes, high amounts of glucose in blood increases certain factors within retinal cells. These factors slowly cause damage, such that after 15 years of diabetes all patients will have some retinal disease and many will loose sight. Indeed, diabetes is the leading cause of blindness in working people. T ....The retina is responsible for sight. Vision occurs by interactions between blood vessels, neurons (cells that transmit electrical signals for vision) and glia (cells that support the retina). In diabetes, high amounts of glucose in blood increases certain factors within retinal cells. These factors slowly cause damage, such that after 15 years of diabetes all patients will have some retinal disease and many will loose sight. Indeed, diabetes is the leading cause of blindness in working people. The main treatment for diabetic retinal disease is to burn away damaged blood vessels, however, this treatment has problems. Firstly, the burns destroy healthy retina and the disease continues, secondly, the treatment is performed late in the disease and therefore does not prevent the early changes in retinal cells, and thirdly, changes in neurons and glia are often not considered. Therefore, there is an urgent need to understand how blood vessels, neurons and glia interact with each other to threaten vision in diabetes, with the intention of developing safer and more effective treatments. This will be the focus of the current project. Currently, there are no studies that have examined the sequential changes in retinal blood vessels, neurons and glia in diabetes. This is mainly due to the lack of an experimental rodent model that progresses from mild to severe diabetic retinal disease. In 2003, we established such a model in the diabetic Ren-2 rat. In this project the diabetic Ren-2 rat will be used to study retinal cell changes and also to identify the factors that damage these cells. We suggest that angiotensin, bradykinin and VEGF are involved. These factors are present in the normal retina and are increased in diabetes. We will block these factors with specific drugs with the intention of understanding how these factors affect retinal cells in diabetes, and also to develop new drug therapies for the treatment of both early and late diabetic retinal disease.Read moreRead less
Atherosclerosis: Molecular Mechanisms Of Suppression By CD4+CD25+ Regulatory T-cells
Funder
National Health and Medical Research Council
Funding Amount
$535,333.00
Summary
Atherosclerosis, or hardening of large arteries is the underlying cause of up to 50% of deaths in Western communities, primarily from heart attacks and strokes. Today it is considered a chronic inflammatory disease arising from the accumulation of fats such as cholesterol into the inner lining of blood vessels including those supply vital organs such as the heart and brain. This study focuses on understanding how to use the body's own anti-inflammatory cells suppress inflammation.
Atherosclerosis: Molecular Action And Suppression Of NKT Cell Subsets
Funder
National Health and Medical Research Council
Funding Amount
$458,815.00
Summary
Atherosclerosis, or hardening of large arteries, is the underlying cause of up to 50% of deaths in Western communities from heart attacks and strokes. Today it is considered a chronic inflammatory disease arising from the influx of fats such as cholesterol into the inner liming of arteries that provide blood supply to organs such as the heart and the brain. However, the exact role that inflammation plays in the development of this blood vessel disease is poorly understood. This study is directed ....Atherosclerosis, or hardening of large arteries, is the underlying cause of up to 50% of deaths in Western communities from heart attacks and strokes. Today it is considered a chronic inflammatory disease arising from the influx of fats such as cholesterol into the inner liming of arteries that provide blood supply to organs such as the heart and the brain. However, the exact role that inflammation plays in the development of this blood vessel disease is poorly understood. This study is directed towards understanding the role of a subset of while blood cells known as NKT cells in the inflammatory process. In particular we will examine whether the activity of NKT cells in promoting atherosclerosis can be controlled either by the administration of drugs that deprive them of molecules that stimulate their activity and-or by the injection of another population of white blood cells known as regulatory T cells that may to limit their activity. Our preclinical study of atherosclerosis in mice has potential for extension to the control of atherosclerosis in humans. Successful translation in this way can be expected to provide a significant health benefit.Read moreRead less
Characterisation Of Conserved Sox18-dependent Genes In Lymphatic Vascular Development
Funder
National Health and Medical Research Council
Funding Amount
$401,355.00
Summary
Lymphatic vessels are important in a number of diseases including lymphoedema and cancer. There is a significant gap in our basic understanding of how lymphatic vessels form. We have identified a series of genes that are regulated downstream of the lymphatic master gene Sox18 in mouse lymphatic vessels. This study aims to characterise these genes using complementary model systems. The genes and pathways identified will represent potential therapeutic targets in a number of disease contexts.
Regulator Of G-protein Signalling-5: A Key Modulator Of Vascular Maturation And The
Funder
National Health and Medical Research Council
Funding Amount
$548,396.00
Summary
Tumours progressively grow in part because they escape destruction by the immune system. New blood vessels grow inside tumours by a process called angiogenesis, which in turn stops disease-fighting cells in their tracks. However, we have now discovered that it is possible to reverse angiogenesis by normalising the blood vessels. This effectively means the barriers are broken down and the tumour can be opened to the immune system or cancer fighting drugs. Furthermore, we have identified a protein ....Tumours progressively grow in part because they escape destruction by the immune system. New blood vessels grow inside tumours by a process called angiogenesis, which in turn stops disease-fighting cells in their tracks. However, we have now discovered that it is possible to reverse angiogenesis by normalising the blood vessels. This effectively means the barriers are broken down and the tumour can be opened to the immune system or cancer fighting drugs. Furthermore, we have identified a protein which appears to be very important for normalisation, a process which is currently not well understood. This proposal continues our pioneering work on vessel normalisation and will use models of highest clinical relevance to study the dynamics of vessel remodelling in tumours. Our approach is different to current angiogenesis research which simply tries to block or destroy the blood vessels that feed tumours. We expect our findings to lead to highly specific and effective anti-tumour therapies. Moreover, vessel growth in tumours has striking parallels to other vascular processes in the body, which have important implications for major and common human diseases such as high blood pressure and atherosclerosis. We now have the tools to study these processes and their abnormalities in our newly established disease model. By gaining insight into these disorders we will be able to develop novel approaches to stop disease progression.Read moreRead less
The Role Of Platelet Derived Growth Factor Receptor Alpha (Pdgfra) In Coronary Vascular Progenitor Cells
Funder
National Health and Medical Research Council
Funding Amount
$666,840.00
Summary
The coronary vessels supply blood to heart muscle. Blockage of coronary vessels causes heart attacks which are the leading cause of death in the Western world. A recent focus for heart attack researchers is to re-establish the blood supply to the injured area by creating new blood vessels. We have found a new gene involved in creating coronary blood vessels. We will characterize how this gene is involved in this process. Knowledge about this gene may foster new treatments for heart attack.
Role Of Indoleamine 2,3-dioxygenase In Vascular Disease
Funder
National Health and Medical Research Council
Funding Amount
$271,500.00
Summary
Atherosclerosis and its clinical presentation including heart attack and stroke represent a major source of morbidity and mortality in the developed world, including Australia. Atherosclerosis involves the accumulation of lipid-laden cells in the wall of arteries that generates plaques resulting in a decrease in the lumen of the affected vessel that can impede or block blood flow resulting in clinical complications. The cellular events involved in atherosclerosis are complex. However, increasing ....Atherosclerosis and its clinical presentation including heart attack and stroke represent a major source of morbidity and mortality in the developed world, including Australia. Atherosclerosis involves the accumulation of lipid-laden cells in the wall of arteries that generates plaques resulting in a decrease in the lumen of the affected vessel that can impede or block blood flow resulting in clinical complications. The cellular events involved in atherosclerosis are complex. However, increasing information indicates that atherosclerosis involves an inappropriate response of the immune and inflammatory systems. This proposal plans to investigate the role of a protein, indoleamine 2,3-dioxygenase (IDO) that is increased during inflammation and is important for the regulation of the host's immune system. We propose that increasing IDO activity in inflammatory cells will attenuate the degree of vascular disease by decreasing the overall level of immune activation and inflammation in the blood vessels. We will test this by modulating the expression and activity of this protein in animal models of vascular disease, measure the extent of disease and then elucidate the mechanisms by which the protein acts. The significance of these studies is that they will provide useful information on the inflammatory and immune processes involved in the progression of atherosclerosis and may identify a potential novel target for therapeutic intervention.Read moreRead less
Cellular And Molecular Mechanisms Of Human Choroidal And Retinal Vascularisation
Funder
National Health and Medical Research Council
Funding Amount
$288,210.00
Summary
The abnormal growth of new blood vessels is a major cause of blindness in people of all ages. In premature infants, changes in retinal blood vessels results in Retinopathy of Prematurity (ROP) the leading cause of infant blindness in the world. In older adults with age-related macular degeneration (ARMD), vessels in the choroid can grow into and under the retina where they can cause catastrophic loss of vision. This association of abnormal vessel growth with the most common causes of blindness h ....The abnormal growth of new blood vessels is a major cause of blindness in people of all ages. In premature infants, changes in retinal blood vessels results in Retinopathy of Prematurity (ROP) the leading cause of infant blindness in the world. In older adults with age-related macular degeneration (ARMD), vessels in the choroid can grow into and under the retina where they can cause catastrophic loss of vision. This association of abnormal vessel growth with the most common causes of blindness has motivated the search for a better understanding of how blood vessel growth in the eye is controlled in healthy tissues and how these controls fail in disease. Our proposal addresses this issue directly. Recent work shows that this neovascularization is not only a response to a rise in the local concentration of molecules that induce such angiogenesis, but also requires a fall in the levels of endogenous molecules that inhibit angiogenesis. Our study will investigate the expression of newly identified angiogenic growth factors (VEGFs) and their receptors as well as angiogenic inhibitors (VEGI and PEDF) in the developing and adult human retina and choroid. We will examine the mechanisms by which the human choroid is formed. Our preliminary results suggests the novel insight that vasculogenesis (the formation of blood vessels via transformation of vascular precursor cells) plays a major role the formation of both the human retina and choroid. Further, these exciting results suggest involvement of novel growth stimulators and inhibitors previously not known to play a role in these processes. Our studies will lead to new insights regarding the vascular growth factors and inhibitors that drive this process, thus leading to a rational basis for new therapeutic targets for the treatment of ARMD. The rapid aging of the Australian population and the consequent predicted doubling of ARMD incidence in the next 20 years demonstrates the urgency of our studies.Read moreRead less
Do Postjunctional Alterations Explain The Effects Of Diabetes On Neurovascular Transmission?
Funder
National Health and Medical Research Council
Funding Amount
$390,886.00
Summary
Diabetes produces disordered skin blood flow that increases risk of skin ulcers and gangrene. The project investigates nervous control of skin blood vessels in diabetes. It is assumed that all affects of diabetes on nerve function are explained by loss of nerves. We hypothesize that some affects of diabetes are due to dysfunction of blood vessels and not to nerve loss. The objective is to identify drug targets to improve blood flow in skin and thereby reduce the risk of skin ulcers and gangrene.