Role Of JNK And P38 MAPK Signalling In Diabetic Nephropathy
Funder
National Health and Medical Research Council
Funding Amount
$454,500.00
Summary
Renal failure is a major health problem in our community. Patients who progress to end-stage renal failure are dependent upon lifelong dialysis or transplantation (an expensive and complex treatment). The past decade has seen a dramatic increase in the number of patients developing end-stage renal failure, mainly due to increasing rates of diabetic kidney disease. Indeed, the recent AusDiab nationwide survey that identified diabetes or glucose intolerance (a precursor to diabetes) is now present ....Renal failure is a major health problem in our community. Patients who progress to end-stage renal failure are dependent upon lifelong dialysis or transplantation (an expensive and complex treatment). The past decade has seen a dramatic increase in the number of patients developing end-stage renal failure, mainly due to increasing rates of diabetic kidney disease. Indeed, the recent AusDiab nationwide survey that identified diabetes or glucose intolerance (a precursor to diabetes) is now present in up to 25% of the adult Australian population. Around 50% of diabetics develop kidney disease and, despite recent advances in better control of blood glucose and blood pressure, kidney disease in most diabetic patients will inexorably progress to end-stage renal failure. Therefore, there is an urgent need to improve treatment strategies in diabetic patients to avoid kidney failure. We have identified a group of proteins (enzymes called JNK and p38) within cells that play a causal role in the development of non-diabetic forms of kidney disease. Most recently, we have shown that an increase in the activity of these proteins (JNK and p38) is associated with the development of human and experimental diabetic kidney disease. Therefore, this project will block the action of JNK and p38 using two complementary approaches (pharmaceutical drugs and genetically modified mice) to determine whether targeting these proteins can suppress the development of diabetic kidney disease. In addition, there is evidence to suggest that blockade of these proteins may have a beneficial impact upon insulin resistance and elevated blood glucose in type 2 diabetes. If these postulates are proven, this will provide a well-defined therapeutic target for the treatment of diabetic kidney disease, and perhaps diabetes itself. Furthermore, since inhibitors of these proteins are already in clinical trials for other indications, targeting this mechanism in diabetic kidney disease is a realistic goal.Read moreRead less
C-Jun N-terminal Kinase Actions In The Response To Stress
Funder
National Health and Medical Research Council
Funding Amount
$480,127.00
Summary
All cells in our body sense and respond to stressful changes in our environment. We are focused on enzymes called JNKs that relay this information, and so form part of the key response pathways. JNKs are now being evaluated as new drug targets for the treatment of diseases including diabetes and stroke, but we know very little about how JNKs work in stressed cells. We will define new partners for the JNKs and in so doing reveal new information on the stress-activated events they regulate.
MIF Regulation Of MKP-1 And Glucocorticoid Responses In RA
Funder
National Health and Medical Research Council
Funding Amount
$398,156.00
Summary
Rheumatoid arthritis (RA) is a common chronic inflammatory disease which affects 1% of Australians. Up to 70% of patients are treated with 'steroids', which are drugs with major side effects. Recent research has shown that sensitivity to steroids is controlled by a number of natural proteins, and that balance between these proteins controls the effectiveness of steroids. The proposed research will define the interactions between these proteins.
The Role Of PAC-1 In Leukocyte Activation And Inflammatory Responses
Funder
National Health and Medical Research Council
Funding Amount
$465,750.00
Summary
The MAP kinase pathway is fundamental for signalling a variety of cellular responses. This pathway is particularly important for immune responses ie. cytokine signalling, chemotaxis, and proliferation. PAC-1, a MAP kinase phosphatase, is an important regulator of this pathway. Extensive gene profiling of various immune cells using Affymetrix GeneChips identified PAC-1 as a highly regulated molecule in activated mast cells. Mast cells are important inflammatory cells, particularly for rheumatoid ....The MAP kinase pathway is fundamental for signalling a variety of cellular responses. This pathway is particularly important for immune responses ie. cytokine signalling, chemotaxis, and proliferation. PAC-1, a MAP kinase phosphatase, is an important regulator of this pathway. Extensive gene profiling of various immune cells using Affymetrix GeneChips identified PAC-1 as a highly regulated molecule in activated mast cells. Mast cells are important inflammatory cells, particularly for rheumatoid arthritis and asthma. We have shown that PAC-1 deficient mice are highly protected from inflammation and disease in a mouse model of rheumatoid arthritis. This grant aims to extend these exciting initial findings to other inflammatory diseases, particularly asthma and type 1 Diabetes, and to establish the basis for PAC-1 inhibition of disease. This research should establish PAC-1 as a new and important target for inflammatory disease, provide understanding on inflammatory processes, and possibly lead to improved therapies for diseases such as rheumatoid arthritis.Read moreRead less
Alternate Signalling Pathways Regulating The Human Arachidonate Epoxygenase CYP2J2 In Response To Stress Stimuli
Funder
National Health and Medical Research Council
Funding Amount
$369,000.00
Summary
Hypoxia, or oxygen deprivation, is caused by the decreased supply of blood to cells and is a component of ischaemic injury to the cardiovascular system (e.g. stroke, atherosclerosis) and numerous other organs (e.g. cancer and chemical mediated injury). It is now known that an important group of proteins that switch on specialised target genes in response to hypoxia is Activator-Protein-1 (AP-1). We have found that cytochrome P450 2J2 (CYP2J2), which is an enzyme that forms beneficial fatty acid ....Hypoxia, or oxygen deprivation, is caused by the decreased supply of blood to cells and is a component of ischaemic injury to the cardiovascular system (e.g. stroke, atherosclerosis) and numerous other organs (e.g. cancer and chemical mediated injury). It is now known that an important group of proteins that switch on specialised target genes in response to hypoxia is Activator-Protein-1 (AP-1). We have found that cytochrome P450 2J2 (CYP2J2), which is an enzyme that forms beneficial fatty acid products inside cells, is decreased in hypoxia and that this is due to increased activity of AP-1. We know that similar stressful stimuli can also result in a loss of CYP2J2. Again, AP-1 is involved but we have further evidence for the role of another pathway. This project will explore how these pathways operate individually and together to decrease CYP2J2. Studying the regulation of human genes is difficult because we can not readily monitor their levels in cells in either healthy or sick individuals. So we will make transgenic mouse models to study human CYP2J2 regulation, which will provide information on the human situation. In this project we will identify which factors switch off the CYP2J2 transgene and will analyse the signalling pathways within cells that control this response. The importance of these studies is that they will help us to design pharmacological strategies to prevent the loss of CYP2J2 in cells that are stressed. Such agents may be effective in the treatment of ischaemic injury seen in stroke and atherosclerosis. If we can maintain CYP2J2 levels we may be able to maintain the beneficial fatty acid levels in cells and have a novel therapeutic approach for keeping cells alive.Read moreRead less
Hormonal Resuscitation And P38 MAP Kinase Inhibition To Enhance Quality Of Cadaveric Donor Organs For Transplantation
Funder
National Health and Medical Research Council
Funding Amount
$469,500.00
Summary
The transplantation of organs such as the heart, lung, liver, kidney and pancreas from brain-dead donors is limited primarily by the shortage of donor organs. It is now recognised that as many as 25% (one in four) potentially usuable donor organs are lost after brain death due to the rapid deterioration that occurs in organs after brain death. There is evidence that this deterioration is due to loss of the normal hormones that are essential to the normal functioning of these organs. In this proj ....The transplantation of organs such as the heart, lung, liver, kidney and pancreas from brain-dead donors is limited primarily by the shortage of donor organs. It is now recognised that as many as 25% (one in four) potentially usuable donor organs are lost after brain death due to the rapid deterioration that occurs in organs after brain death. There is evidence that this deterioration is due to loss of the normal hormones that are essential to the normal functioning of these organs. In this project, we will use a pig model of brain death that we have extablished in our laboratory to examine the effects of hormone replacement on the function of organs that are used for transplantation. We will also test a novel drug aimed at protecting donor organs during the period between removal of the organ and transplantation. If successful, these treatments have the potential to markedly increase the numbers of organ transplants and to improve the outcomes for recipients of these transplants. In the Australian and New Zealand setting, a 25% increase in the number of donor organs would results in approximately 220 more people per year receiving these life-saving operations.Read moreRead less