The Role Of Connexins In Blood Pressure Regulation: Use Of A Conditional Gene Expression System
Funder
National Health and Medical Research Council
Funding Amount
$583,767.00
Summary
Cell coupling through gap junctions is said to play an important role in regulating blood flow and blood pressure. However data obtained from mice, in which specific gap junctions are deleted, may be compromised by compensatory changes in other junctions. We have validated a new method for rapidly and reversibly altering gap junctions in adult mice with oral sugar. This technique will enable us to directly determine whether interference with cell coupling affects blood flow and blood pressure.
Characterisation Of PAR2 Knockout And Transgenic Mice: Towards Gene Therapy For Epithelia Based Inflammatory Diseases
Funder
National Health and Medical Research Council
Funding Amount
$486,943.00
Summary
Debilitating and sometimes fatal diseases like asthma and rheumatoid arthritis urgently require new approaches for their effective management and hopefully, cure. We have recently discovered that the airways posses a powerful and naturally-occuring protective mechanism which is regulated by unique molecules in the membranes of the lining cells of the air passages. These molecules are called protease-activated receptors, or PARs, and are also found on cells lining the inner surfaces of blood vess ....Debilitating and sometimes fatal diseases like asthma and rheumatoid arthritis urgently require new approaches for their effective management and hopefully, cure. We have recently discovered that the airways posses a powerful and naturally-occuring protective mechanism which is regulated by unique molecules in the membranes of the lining cells of the air passages. These molecules are called protease-activated receptors, or PARs, and are also found on cells lining the inner surfaces of blood vessels and joints as well as in skin. We are fortunate to have strains of mice - a species in which the PAR-mediated protective mechanism is well developed - in which the gene for the most important of the PARs found in the lung, PAR2, is missing. These animals are called PAR2 'knock-outs'. We also have another strain of mouse in which the human PAR2 gene has been inserted back into PAR2 knock-out mice. These animals will allow us to determine the importance of PAR2 in protection against asthma, arthritis, vascular disease and deficiencies in skin healing, as well as how PAR2 might be a more effective protective agent in mice rather than humans. Thus, modification of the human gene to make the protective system work as effectively as in the mouse might provide an effective therapy or cure for diseases of the lungs, joints and skin as well as in vascular diseases.Read moreRead less
Understanding Local And Regional Determinants Of EDHF And NO Dysfunction In Resistance Arteries In Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$771,295.00
Summary
Diabetes is a serious and increasing health burden worldwide. Most of the sickness and death associated is due to complications arising in the blood vessels. The inner lining of blood vessels in small arteries uses several different mechanisms to ensure proper blood flow, and in diabetes these are impaired. This study will reveal the cellular mechanisms involved and identify pathways for therapeutic intervention to alleviate the debilitating effects of small artery disease.
The Vasoprotective Actions Of Flavonoids In Ischaemia And Hypercholesterolaemia
Funder
National Health and Medical Research Council
Funding Amount
$181,018.00
Summary
Diet has a major influence on the incidence of coronary artery disease. Thus in populations where large amounts of fruits, vegetables and legumes are consumed with a low proportion of food from animal sources there is a relatively lower incidence of coronary artery disease. A possible explanation for the beneficial actions of this diet is that it provides a high level of compounds called flavonoids. Flavonoids have a number of biological actions that may prevent coronary artery disease. Flavonoi ....Diet has a major influence on the incidence of coronary artery disease. Thus in populations where large amounts of fruits, vegetables and legumes are consumed with a low proportion of food from animal sources there is a relatively lower incidence of coronary artery disease. A possible explanation for the beneficial actions of this diet is that it provides a high level of compounds called flavonoids. Flavonoids have a number of biological actions that may prevent coronary artery disease. Flavonoids can relax blood vessels which would improve blood flow to organs. In addition they may lower the level of LDL cholesterol, the bad form of cholesterol that promotes artery narrowing. They may also have actions that prevent damage that normally occurs to organs when there is an interruption to blood flow, such as occurs when someone has a heart attack or stroke. This project will investigate the ability of selected flavonoids to prevent injury to blood vessels that occurs when there is an interruption to blood flow or when cholesterol levels are too high. Understanding the actions of flavonoids may lead to the development of new therapies to prevent or treat heart attacks and stroke.Read moreRead less
Heme-oxidised Soluble Guanylyl Cyclase, A Mechanism-based Target For Vascular Diagnostics And Vasoprotective Therapy
Funder
National Health and Medical Research Council
Funding Amount
$524,456.00
Summary
Nitric oxide is produced in the inner lining of blood vessels and maintains blood flow via binding to a specific protein, sGC. In disease, sGC is defective and can be targeted by a novel group of drugs which are more active in diseased versus normal blood vessels. This project will examine the use of these drugs as markers of cardiovascular disease and in the treatment of high cholesterol and may lead to the development of new diagnostic tools and therapies for vascular complications.
Aberrant Oligosaccharide Processing Of Nox2-oxidase As A Mechanism Of Vascular Oxidative Stress In Atherosclerosis
Funder
National Health and Medical Research Council
Funding Amount
$552,565.00
Summary
Excessive production of free radicals by an enzyme called Nox2 may be a cause of artery disease leading to heart attacks and strokes. This study will identify whether the addition of sugarchains to Nox2 causes it to be expressed at the surface of cells allowing the free radicals it produces to exit the cell and cause damage to the blood vessel wall. Charaterising this new pathway of excessive free radical production may pave the way for new diagnostics and treatments for artery disease.
MECHANISMS OF CEREBROVASCULAR REGULATION IN HEALTH AND DISEASE
Funder
National Health and Medical Research Council
Funding Amount
$216,430.00
Summary
Failure of the cerebral circulation to meet the brain's immediate high nutritive requirements results in stroke in just a few minutes. Stroke continues to be a major cause of death and disability, and this major medical challenge requires urgent and significant research at the basic level to better understand mechanisms of normal, and then abnormal, regulation of cerebral artery function. The project will examine the importance of a novel mechanism in regulating brain blood flow by affecting the ....Failure of the cerebral circulation to meet the brain's immediate high nutritive requirements results in stroke in just a few minutes. Stroke continues to be a major cause of death and disability, and this major medical challenge requires urgent and significant research at the basic level to better understand mechanisms of normal, and then abnormal, regulation of cerebral artery function. The project will examine the importance of a novel mechanism in regulating brain blood flow by affecting the degree of opening of the cerebral arteries. This mechanism involves activation of an enzyme, Rho-kinase, which is present in the wall of blood vessels. The applicants believe that this process plays an important role in the normal, healthy regulation of blood supply to the brain. Moreover, there are strong reasons for us to speculate that the function of this enzyme is abnormally high in two disease states that are associated with an increased risk of stroke - high blood pressure and subarachnoid haemorrhage. We will employ a variety of techniques to assess the importance of Rho-kinase in cerebral artery function in the living body, and also in isolated segments of artery. The results are expected to provide major new insight into mechanisms that regulate brain blood flow, and the knowledge gained here may lead to better therapies to prevent or treat stroke.Read moreRead less
Does NADPH Oxidase Link Gender, Hormone Replacement Therapy And Outcome After Stroke?
Funder
National Health and Medical Research Council
Funding Amount
$481,439.00
Summary
This project will assess whether the reduction of a novel mechanism to open brain arteries (i.e. via activation of 'Nox' proteins and generation of oxygen radicals) is a possible explanation of why hormone replacement therapy (HRT) increases the risk of stroke in postmenopausal women. We will compare brain artery function of normal mice with those deficient in certain Nox genes in models of menopause, HRT and stroke. This knowledge should lead to safer stroke therapies in women and men.