How Is Lipoprotein Disposition Influenced By Fenestrae In The Hepatic Sinusoidal Endothelium?
Funder
National Health and Medical Research Council
Funding Amount
$310,500.00
Summary
Understanding lipoprotein metabolism is critical for the prevention of vascular disease. The liver is the main site for lipoprotein metabolism. The initial step in the metabolism of lipoproteins by the liver is their transfer across the liver sinusoidal endothelial cells from the blood to the liver cells. Sinusoidal endothelial cells contain pores called fenestrae that are thought to allow direct passage of large substances and thus filter lipoproteins on the basis of size. We propose to fully d ....Understanding lipoprotein metabolism is critical for the prevention of vascular disease. The liver is the main site for lipoprotein metabolism. The initial step in the metabolism of lipoproteins by the liver is their transfer across the liver sinusoidal endothelial cells from the blood to the liver cells. Sinusoidal endothelial cells contain pores called fenestrae that are thought to allow direct passage of large substances and thus filter lipoproteins on the basis of size. We propose to fully define the role of fenestrae in the ultrafiltration of particles such as lipoproteins and microspheres. This will confirm that ultrafiltration by fenestrae in the liver endothelium is an important biological process akin to filtration by the kidney, and relevant for lipoprotein metabolism. We will determine whether oxidative stress, which generates large gaps in the sinusoidal endothelium, increases the transfer of lipoproteins into the liver. This provides a novel mechanism for fatty liver that follows toxic liver injury, and hence, a therapeutic target for this condition. We will determine whether loss of fenestrae induced by the synthetic non-ionic surfactant, pluronic 407, reduces transfer of lipoproteins. This is an entirely novel mechanism and risk factor for hyperlipidaemia. Finally we will investigate lipoprotein (a) which is a potent risk factor for vascular disease. We will assess with lipoprotein (a), through binding other lipoproteins and increasing their size, impedes their transfer through the fenestrations for subsequent hepatic metabolism. From the basic perspective, these studies will prove that fenestrations in the liver endothelial cell are an ultrafiltration system that is significant for lipoprotein metabolism. From the clinical perspective, the studies will generate novel mechanisms for impaired hepatic metabolism of lipoproteins as well as indicating that fenestrae are a potential target for the development of lipid-lowering pharmacotherapies.Read moreRead less
Relationship Between Cell-cell Interactions And Disease Severity In Patients With Cerebral Malaria
Funder
National Health and Medical Research Council
Funding Amount
$545,183.00
Summary
Severe malaria is a collection of disease complications that leads to about 2 million deaths each year worldwide. Young children in Africa and young adults in several parts of South-East Asia are particularly affected. Travellers to these regions are also at considerable risk. One of the most dangerous complications of malaria is when the brain becomes affected, which is called cerebral malaria. We still do not understand enough about the changes that link the parasite circulating in the blood w ....Severe malaria is a collection of disease complications that leads to about 2 million deaths each year worldwide. Young children in Africa and young adults in several parts of South-East Asia are particularly affected. Travellers to these regions are also at considerable risk. One of the most dangerous complications of malaria is when the brain becomes affected, which is called cerebral malaria. We still do not understand enough about the changes that link the parasite circulating in the blood with the devastating disturbance of brain function that causes death in some people who develop cerebral malaria. In this project we will investigate some new ideas about how cerebral malaria develops. We will perform a detailed study of brain tissue taken from victims of cerebral malaria and compare the observations with similar ones in children who died of other causes. Then we will work with an experimental model we have developed, in which we put together in culture flasks the various types of cell that are found in the brain lesions in people who die from cerebral malaria. Our aim is to identify some new therapeutic targets for later use in treatment of cerebral malaria patients.Read moreRead less
B Cell Activation Generates Antibodies To Promote Vascular And Renal Inflammation, Remodelling And Dysfunction In Hypertension
Funder
National Health and Medical Research Council
Funding Amount
$327,193.00
Summary
Hypertension is a major contributor to chronic cardiovascular and renal diseases, with recent literature suggesting the pathogenesis is similar to that of autoimmune diseases. This fellowship will enhance the current understanding of the pathogenesis of hypertension and the associated inflammation of the kidneys and vasculature. It will also assess the therapeutic potential of drugs that dampen the immune response in several animal models of hypertension.
The Involvement Of The Kynurenine Pathway In Blood Brain Barrier Disruption And Its Relevance For Neuroinflammatory Diseases
Funder
National Health and Medical Research Council
Funding Amount
$597,797.00
Summary
We aim to study the involvement of molecules deriving from the degradation of the essential amino acid tryptophan on the breakdown of the ñblood-brain barrierî (the cellular wall separating blood and brain) that is observed in several major brain diseases. Using specific drugs blocking the production or the effects of these toxic compounds we expect to be able to preserve the integrity of the blood brain barrier and so to limit brain inflammation and neuronal loss.
New Insights Into The Role Of Renal Endothelial Dysfunction In The Pathogenesis Of Glomerular Injury And Renal Fibrosis
Funder
National Health and Medical Research Council
Funding Amount
$577,722.00
Summary
This project will ascertain whether abnormal function of endothelial cells contribute to diabetic and non-diabetic kidney diseases, the leading cause of end-stage kidney disease. The outcome of this study will allow us to reevaluate the role of endothelial cells in kidney scarring, lead us to question our current approaches to the treatment and management of chronic kidney disease and eventually may be helpful for the design of novel therapies to treat chronic kidney diseases.
Contribution Of Bone Marrow-derived Cells To Renal Fibrosis And Elucidation Of Cell Signalling Mechanisms
Funder
National Health and Medical Research Council
Funding Amount
$427,703.00
Summary
This study investigates the contribution of bone marrow-derived adult stem cells to the development of renal scarring, an important process proceeding to end-stage renal disease (ESRD). There is increasing evidence demonstrating that bone marrow (BM)-derived cells can transform into renal cells and participate in the repair of damaged renal blood vessels. Our recent study demonstrated BM-derived stem cells can also transform to renal myofibroblasts, the major cell type that contributes to the de ....This study investigates the contribution of bone marrow-derived adult stem cells to the development of renal scarring, an important process proceeding to end-stage renal disease (ESRD). There is increasing evidence demonstrating that bone marrow (BM)-derived cells can transform into renal cells and participate in the repair of damaged renal blood vessels. Our recent study demonstrated BM-derived stem cells can also transform to renal myofibroblasts, the major cell type that contributes to the development of kidney scarring. This suggests that BM-derived adult stem cells have dual roles: to repair or worsen the development of renal scarring. The present study investigates this adult stem cell's transformation and explores the potential measures to enhance the benefits and to block the harmful roles from these adult stem cells. The importance of BM-derived stem cells in the repair of damaged kidney will be determined and thus will provide preliminary insights into the future utilization of BM-derived stem cells in the treatment of chronic renal disease. Understanding the dual roles of BM-derived stem cells in experimental renal scarring, will lead us to question our current thinking and approaches to the treatment and management of renal fibrosis, and perhaps fibrosis in other organs. Evidence of two opposite roles which BM-derived adult stem cells play in the process of renal scarring may be helpful not only for the design of novel therapies to prevent or retard the progression of renal fibrosis, but also for manipulating adult stem cells for the treatment of renal disease.Read moreRead less
Improved Formulations Of Anti-cancer Agents 5-Fluorouracil And Oxaliplatin Using Excipient Technology
Funder
National Health and Medical Research Council
Funding Amount
$202,973.00
Summary
Chemotherapy plays a key role in cancer treatment, however, problems persist with severe adverse toxic effects. Combinations of anti-cancer agents give better results, but these agents still have major negative effects, for example, on veins and peripheral nerves and they must be given separately. We have developed a novel, all-in-one formulation of Oxaliplatin with 5-Fluorouracil and Leucovorin, with the potential for fewer toxic effects and improved patient care.
Porphyromonas Gingivalis Cysteine Proteinases In Modulation Of Cell-mediated Immune Response In Periodontitis
Funder
National Health and Medical Research Council
Funding Amount
$228,000.00
Summary
Chronic inflammatory diseases of the tissues supporting the teeth comprise some of the most widespread and common diseases to affect mankind. Recent research has indicated the major contributor to the most common form of destructive periodontal disease is the bacterium Porphyromonas gingivalis. This organism produces powerful enzymes which overcome the body's attempts to neutralise them. It is also known that the destructive phase of the disease is characterised by a change in the behaviour of t ....Chronic inflammatory diseases of the tissues supporting the teeth comprise some of the most widespread and common diseases to affect mankind. Recent research has indicated the major contributor to the most common form of destructive periodontal disease is the bacterium Porphyromonas gingivalis. This organism produces powerful enzymes which overcome the body's attempts to neutralise them. It is also known that the destructive phase of the disease is characterised by a change in the behaviour of the immune system cells which accumulate in the diseased tissues. This is manifest as a loss of protective immunity and replacement by ineffective or even tissue damaging responses. Critical in directing the pattern of behaviour of the immune system cells are the potent messenger molecules or cytokines which pass between cells. We have demonstrated that the bacterial proteinases can destroy a critical messenger molecule that instructs the defensive phagocytic cells to attack bacteria. These cells in return normally send a powerful signal back to the controlling T lymphocyte to amplify the protective signals. Associated bacterial molecules stimulate more secretion of messenger molecules which are paradoxically destroyed by the bacterial enzymes. This could cause chaos in the local tissue environment. Further, the bacterial proteinases can also eliminate some important surface molecules of T lymphocyte that are important in the activation process. The effect of this could produce impairment of T lymphocyte at periodontal sites. The planned research will define how the proteinases modulate T lymphocyte immune response. Further, the relation between the capacity of the bacterial enzymes to disrupt the vascular cells and the progression of periodontitis will also be determined.Read moreRead less
Role Of Myeloperoxidase In Endothelial Barrier Dysfunction During Inflammation
Funder
National Health and Medical Research Council
Funding Amount
$302,123.00
Summary
The release of the enzyme myeloperoxidase (MPO) within blood vessels is thought to affect their ‘leakiness’ during periods of inflammation, leading to fluid associated swelling (oedema). We propose that MPO produces oxidant chemicals that increase blood vessel leakage. The aim of our work is to study how these chemicals increase vascular leakage by studying the biochemical pathways involved. These studies could lead to new intervention strategies targeting MPO to reduce excessive tissue oedema.
Understanding The Role Of Cell Death In Blood Vessel Regression And Regrowth
Funder
National Health and Medical Research Council
Funding Amount
$468,059.00
Summary
Blood vessels are essential to distribute oxygen and nutrients throughout our bodies, and as such, disruptions to normal blood vessel behaviour can have significant impacts on health. This research is aimed at understanding how blood vessel networks can regrow after damage in order to maintain healthy blood supply to a tissue. This work will be particularly relevant to diseases where blood vessel loss or inappropriate blood vessel growth occur.