Targeting The Renin Angiotensin System In Liver Fibrosis And Portal Hypertension
Funder
National Health and Medical Research Council
Funding Amount
$643,958.00
Summary
Cirrhosis of the liver due to chronic hepatitis and other common liver diseases is now a major cause of illness and death in Australia. This project will examine how a hormone system called the renin angiotensin system contributes to the development of liver damage in these diseases. We will study whether drugs targeting this system can be used to reduce liver scarring and prevent the development of cirrhosis and its complications.
Effect Of Liver Pathophysiology On Hepatic Pharmacokinetics
Funder
National Health and Medical Research Council
Funding Amount
$457,500.00
Summary
The liver is the main organ in the body for the metabolism and biliary excretion of natural and foreign solutes. Various liver diseases such as cirrhosis, alcoholic liver disease, diet and drug induced fatty livers can affect the uptake and metabolism of drugs and their suitability- dosing needs. Some liver diseases such as fatty livers are very common but how rapidly drugs are metabolised in these patients is not well described. The work is important as it may help us better design new drugs an ....The liver is the main organ in the body for the metabolism and biliary excretion of natural and foreign solutes. Various liver diseases such as cirrhosis, alcoholic liver disease, diet and drug induced fatty livers can affect the uptake and metabolism of drugs and their suitability- dosing needs. Some liver diseases such as fatty livers are very common but how rapidly drugs are metabolised in these patients is not well described. The work is important as it may help us better design new drugs and better choose which drugs to give and, if so, in what doses. In addition, many liver diseases require a biopsy for a definite diagnosis of the likely function of the liver. Estimation of liver function is particularly important in estimating whether there will be sufficient reserve on resection of a cancer or deciding if a liver transplant is needed. The liver is also a very complex organ which can trap or breakdown solutes by a range of different systems. Also of importance is how those diseases affect drug disposition in the liver given that an altered hepatic drug disposition may affect systemic response to the drugs and their metabolites. This work seeks to answer these questions.Read moreRead less
The Role Of The Glutamine Transporter SNAT3 In Ion Transport, Cell Signaling And Ammonia Detoxification
Funder
National Health and Medical Research Council
Funding Amount
$393,249.00
Summary
Hepatic encephalopathy is a syndrome observed in patients with liver cirrhosis and is caused by increased amounts of ammonia in the blood. The proposed project investigates a transporter that is involved in ammonia and glutamine metabolism in liver and brain. The two organs are critical to the pathology of liver failure and ammonia toxicity resulting from reduced liver function. The transporter thus could become a drug target for a variety of liver diseases.
Does Immunosuppression Affect The Post-transplantation Hepatic Fibrogenic Response?
Funder
National Health and Medical Research Council
Funding Amount
$360,000.00
Summary
Liver transplantation is often the only treatment option for patients who progress to end-stage liver disease after initial treatment has failed. Unfortunately, re-emergence of disease is common and patients often develop fibrosis and cirrhosis (scarring of the liver) in the donor organ. In some cases it has been observed that this scarring often develops rapidly, sometimes in a year or less following transplantation. Re-transplantation is often required. This differs from the usual progression ....Liver transplantation is often the only treatment option for patients who progress to end-stage liver disease after initial treatment has failed. Unfortunately, re-emergence of disease is common and patients often develop fibrosis and cirrhosis (scarring of the liver) in the donor organ. In some cases it has been observed that this scarring often develops rapidly, sometimes in a year or less following transplantation. Re-transplantation is often required. This differs from the usual progression of cirrhosis pre-transplant which often takes years or decades to develop. While essential to prevent rejection of the transplanted organ, immunosuppression is not without side effects. To date, few studies have examined the effect of immunosuppressive agents on the development of hepatic fibrosis and the key fibrosis effector cell type, the hepatic stellate cell. These reports have shown that one of the most commonly used immunosuppressant agents (FK-506) may adversely influence fibrosis progression while rapamycin may prevent fibrosis progression. However little is known regarding the mechanisms through which this occurs. We propose to examine the effect of four different immunosuppressants on fibrosis development both in vitro and in vivo to determine whether scar development or scar breakdown pathways are altered post-immunosuppression. If the factors driving the fibrogenesis in the transplanted organ can be elucidated it may then be possible to develop therapeutic strategies to tackle the problem. This may result in a reduced need for re-transplantation which has obvious benefits to the transplant patient but would also reduce the numbers of donor organs required.Read moreRead less
Pharmacodynamics In Liver Disease And In Liver Surgery
Funder
National Health and Medical Research Council
Funding Amount
$899,646.00
Summary
The liver is the main organ in the body for drug metabolism and detoxification. This work seeks to address the poorly understood question: what is the in vivo disposition and response in liver of the drugs for treatment of liver diseases? The results of this work will help us better design new drugs and choose the most effective drugs for liver disease. The research may also help us find a better strategy for liver transplantation and thus improve success rates.
Basic Mechanism Of Spontaneous Tolerance Of Liver Allografts In A Rat Model.
Funder
National Health and Medical Research Council
Funding Amount
$374,625.00
Summary
Many thousands of Australians have a failing liver and the only treatment for this is a liver transplant. Liver transplantation is a major life-saving strategy and hundreds of Australians are rescued each year who would otherwise have died. Rejection of the transplant is the major problem affecting these patients. This project investigates an animal model where a transplanted rat liver is not rejected, even though the recipient receives no treatment. Previous studies from our group have shown th ....Many thousands of Australians have a failing liver and the only treatment for this is a liver transplant. Liver transplantation is a major life-saving strategy and hundreds of Australians are rescued each year who would otherwise have died. Rejection of the transplant is the major problem affecting these patients. This project investigates an animal model where a transplanted rat liver is not rejected, even though the recipient receives no treatment. Previous studies from our group have shown that acceptance is due to donor white blood cells transferred with the liver and based on this finding we are developing treatments that can be used in transplant patients. The current application for funding tests another breakthrough that we have recently made, that treatment of the recipient with a substance called interleukin 4 prevents liver acceptance. This finding shows that interleukin 4, which was previously thought to be involved in preventing transplant rejection, is actually involved in stimulating rejection of the liver. It might therefore be possible to prevent rejection by altering the pattern of its expression, for example, by using an antibody to remove it. This application also aims to examine the overall expression of a very large number of genes in liver transplant acceptance compared with rejection. This will use a new technology called gene array analysis to examine expression of at least 5,000 genes to identify those that are increased during liver acceptance. In addition, gene therapy will be used to increase expression of a single gene called IDO that we and others have found to be associated with transplant acceptance. This gene will be expressed in white blood cells of the liver donor after transplantation to promote liver acceptance and prevent rejection. Ultimately it is intended that these findings will be used to prolong the survival of liver transplant patients by revealing new ways to prevent rejection of liver transplants.Read moreRead less
DEVELOPMENT OF CLINICALLY APPLICABLE STRATEGIES TO INDUCE AND MONITOR LONG TERM ACCEPTANCE OF LIVER ALLOGRAFTS
Funder
National Health and Medical Research Council
Funding Amount
$287,036.00
Summary
Liver transplantation is the only therapy for end-stage liver disease and thousands of Australian lives have been saved with this treatment. The major complication of liver transplantation is rejection which leads to loss of about half of the transplanted livers by ten years. Liver transplants in many animal models are not rejected and function normally for the life of the animal. Using one such animal model we have shown that white cells from the donor are responsible for the absence of rejecti ....Liver transplantation is the only therapy for end-stage liver disease and thousands of Australian lives have been saved with this treatment. The major complication of liver transplantation is rejection which leads to loss of about half of the transplanted livers by ten years. Liver transplants in many animal models are not rejected and function normally for the life of the animal. Using one such animal model we have shown that white cells from the donor are responsible for the absence of rejection. Of interest, these cells appear to stimulate a rapid and extreme immune response, which closely resembles rejection. The main difference is that it is quicker and more marked than rejection and then exhausts itself. This observation is unexpected and suggests possibilities for new treatments. Furthermore it questions the effectiveness of our present treatment for rejection of transplanted livers. We have already shown that some kinds of drugs given to prevent rejection in humans actually have the opposite effect in the animal model and prevent long-term acceptance of liver transplants. The aim of this work is to develop in our animal model a better way of treating human liver transplant patients. This will incorporate injection of donor white cells and treatment with drugs which promote the beneficial effects of these cells. We will also develop ways of testing the blood or the liver of the human liver transplant patients early after transplantation to find out whether the patient is accepting the liver or not. This means that we should be able to try this new treatment method in liver transplant patients once it has been optimised in the animal model.Read moreRead less
Novel Vasoactive Pathways In Liver Disease; Experimental And Clinical Studies
Funder
National Health and Medical Research Council
Funding Amount
$535,333.00
Summary
Cirrhosis of the liver due to chronic hepatitis and other common liver diseases is now a major cause of illness and death in Australia. This project will examine how a hormone system called the renin angiotensin system contributes to the development of liver damage in these diseases. We will study whether drugs targeting this system can be used to reduce liver scarring and prevent the development of cirrhosis and its complications.