The team has been at the forefront of research on type 1 diabetes for over a decade. This form of diabetes is a major chronic disease from childhood, as well as accounting for at least 10% of adult-onset diabetes. It occurs when the body�s immune system attacks and destroys the beta cells in the pancreas that make insulin, the hormone that controls the level of glucose in the blood. The team was one of the first in the world, and is the only one in Australia, to develop screening programs to tes ....The team has been at the forefront of research on type 1 diabetes for over a decade. This form of diabetes is a major chronic disease from childhood, as well as accounting for at least 10% of adult-onset diabetes. It occurs when the body�s immune system attacks and destroys the beta cells in the pancreas that make insulin, the hormone that controls the level of glucose in the blood. The team was one of the first in the world, and is the only one in Australia, to develop screening programs to test and identify people at risk for type 1 diabetes. They showed that the underlying disease could start years before symptoms occurred and discovered genes that determine the rate at which the underlying disease progresses. They have also found evidence that the disease may be triggered by gut viruses called rotaviruses in genetically-susceptible individuals. They showed that type 1 diabetes could be prevented in a mouse model by getting the immune system to make a protective response to insulin, and then went on to apply this in at-risk humans in a controlled trial of intranasal insulin, the first of its kind. They have used genetic techniques not only to pinpoint the mechanisms responsible for killing the beta cells but also to modify the beta cells to make them resistant to attack by these mechanisms. The multidisciplinary approach of the team will be directed to further understanding the genetic and environmental factors underlying type 1 diabetes and the immune mechanisms, particularly involving special white blood cells called T cells, that kill beta cells. A molecular target of the immune attack, the parent of insulin called proinsulin, will be used, paradoxically, as a tool to regulate the immune system and avert the attack. This will be achieved by giving proinsulin via the mucosa of the naso-respiratory tract or via the bone marrow-derived stem cells, initiallyin the mouse model as a test of feasibility for human application. In parallel with these approaches to prevention, specially constructed viruses will be used to transfer several new genes into beta cells to improve their resistance to immune attack, so that they can be transplanted into people with established diabetes without the need for potentially toxic drugs that suppress the immune system overall. The integrated research of the team is helping to provide a sound, rational base for the eventual prevention and cure of type 1 diabetes.Read moreRead less
New Molecular Mechanisms Of Islet Protection Against Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$673,259.00
Summary
Type 2 diabetes is an enormous health and economic burden. The mechanisms of ?-cell compensation for insulin resistance and of ?-cell failure in type 2 diabetes are unclear. This proposal will test the novel hypothesis that the adaptation of endoplasmic reticulum (ER) capacity mediates ?-cell compensation, and that the failure of ?-cell adaptation to ER stress causes diabetes. The studies will show that targeting ER capacity is an important novel strategy for type 2 diabetes therapy.
The Role Of MHC Class I Expression On Pancreatic Ductal Lineage Cells In The Pathogenesis Of Type I Diabetes (TID).
Funder
National Health and Medical Research Council
Funding Amount
$484,300.00
Summary
MHC molecules act as traffic lights to the immune system telling it whether to stop or go, so that only when there is an infection does the immune system receive the signal to destroy target cells. However, the immune system in Type 1 Diabetes patients receives signals to destroy the insulin-producing cells when there is no apparent infection. We aim to determine where the faulty traffic signal occurs and so be in a better position to design intervention strategies to prevent Type 1 Diabetes.
Control Of Insulin Secretion By Y1 Receptor Signalling
Funder
National Health and Medical Research Council
Funding Amount
$675,582.00
Summary
Diabetes is the most common metabolic disease worldwide. Impaired insulin secretion and beta cell function is one of its major causes. We have recently discovered a key signaling pathway that we believe hold the secret to inhibiting insulin secretion in beta cells and blocking it leads to significant insulin release. This proposal focuses on this pathway and its regulation using innovative and unique tools. This will provide a novel treatment option for diabetes as well as islet transplantation.
Biochemical Basis Of Islet Beta-cell Compensation And Failure In Normal Pregnancy And Gestational Diabetes Mellitus
Funder
National Health and Medical Research Council
Funding Amount
$480,828.00
Summary
The factors causing the current world-wide crisis of rapidly rising diabetes prevalence remain poorly understood. Of potential major importance, however, is the hypothesis that abnormalities in the maternal metabolic environment, as occur in gestational diabetes (GDM) (diabetes that develops in pregnancy), result in abnormal development of metabolic systems in the baby resulting in higher risk of adult onset diabetes in the babies. Therefore, it is of importance to understand the mechanisms caus ....The factors causing the current world-wide crisis of rapidly rising diabetes prevalence remain poorly understood. Of potential major importance, however, is the hypothesis that abnormalities in the maternal metabolic environment, as occur in gestational diabetes (GDM) (diabetes that develops in pregnancy), result in abnormal development of metabolic systems in the baby resulting in higher risk of adult onset diabetes in the babies. Therefore, it is of importance to understand the mechanisms causing GDM, such that effective measures can be developed to counter this passing on of diabetes risk from mother to baby. It is known that a key factor causing GDM is failure of maternal pancreatic islet beta-cells to compensate for increased demands for insulin production in pregnancy. Poorly understood, however, are the cellular mechanisms of islet beta-cell compensation in normal pregnancy and failure of this compensation in GDM pregnancy. We have recently shown that there is a pathway of fat metabolism (triglyceride- free fatty acid cycle) within the islet beta-cell that has an important role in amplyfing insulin secretion necessary to maintain normal blood glucose and protecting the islets from failure in obese rats. The major focus of this project is to test the hypothesis that this pathway has a key role in the adaptation of pancreatic islets to normal pregnancy and its dysfunction contributes to the causation of GDM. Of great interest from preliminary findings is that a master regulator of glucose and fat metabolism, PGC1alpha, is markedly reduced in islets during normal pregnancy. Studies will also be directed to PGC1alpha's role in islet adaptation to pregnancy and failure in GDM. We expect that successful completion of this project will lead to the development of highly targeted counter measures to prevent GDM and to slow and reverse the current epidemic of diabetes.Read moreRead less
Expansion, Differentiation And Functional Analysis Of In Vitro Derived Pdx1+ Pancreatic Progenitors
Funder
National Health and Medical Research Council
Funding Amount
$540,075.00
Summary
Type 1 diabetes is a condition that arises when the body's immune system destroys insulin-producing beta cells within the pancreas. Recent studies have shown that normal glucose control can be restored by replacing the missing beta cells by transplantation of cells from deceased donors. However, the demand for transplant material outweighs supply. The work described in this application seeks to define how insulin-producing beta cells can be derived in the laboratory from embryonic stem cells .
Apoptotic Pathways In Pancreatic Beta Cells Leading To Type 1 Diabetes And Transplant Rejection
Funder
National Health and Medical Research Council
Funding Amount
$535,333.00
Summary
The destruction of insulin-producing beta cells in the pancreas by immune cells leads to the need for daily insulin injections in patients with type 1 diabetes. This project aims to understand how beta cells are destroyed. A knowledge of the process by which this occurs will indicate ways we can protect these cells. Our previous work has suggested strategies that may protect beta cells, and we aim to test these. Such protection may eventually allow beta cell replacement by transplantation.
Mechanisms Of Fatty-acid Mediated Destruction Of Pancreatic Beta Cells
Funder
National Health and Medical Research Council
Funding Amount
$510,476.00
Summary
Type 2 diabetes is associated with obesity, but not all obese individuals develop the disease. Non-diabetic obese subjects are able to compensate for diminished sensitivity to insulin (a general feature of obesity) by enhanced output of insulin from the pancreatic beta-cells of the islet of Langerhans. In diabetics this compensatory mechanism is disrupted. Obesity and Type 2 diabetes are also associated with elevated levels of fatty acids (FAs) in the bloodstream. These can be taken up by the be ....Type 2 diabetes is associated with obesity, but not all obese individuals develop the disease. Non-diabetic obese subjects are able to compensate for diminished sensitivity to insulin (a general feature of obesity) by enhanced output of insulin from the pancreatic beta-cells of the islet of Langerhans. In diabetics this compensatory mechanism is disrupted. Obesity and Type 2 diabetes are also associated with elevated levels of fatty acids (FAs) in the bloodstream. These can be taken up by the beta-cells where they exert both short and long-term effects. In the longer term FAs can be toxic to beta-cells and this is thought to be important in the failure of beta-cell compensation. The project is aimed at a better understanding of the manner by which different types of FAs influence the susceptibility of beta-cells to destruction. It builds on our preliminary results suggesting that the capacity of the beta-cell to convert saturated FAs to unsaturated FAs helps protect them from destruction. Our aim is to examine the mechanisms underlying this protection.Read moreRead less
ARC, A Newly Identified Regulator Of Chondrocyte Differentiation And Death, Is A Novel Therapeutic Target For OA
Funder
National Health and Medical Research Council
Funding Amount
$763,983.00
Summary
We have identified a critical regulator of the survival and normal metabolism of the cells in articular cartilage. Loss of this molecule is an early event in joint injury that leads to osteoarthritis (OA). The current proposal will determine the mechanisms whereby this protein functions to protect cartilage breakdown in OA, how its levels in chondrocytes are regulated in both healthy and diseased conditions, and at what stages of disease increasing its expression protects against OA progression.
Diabetes mellitus is a disease reaching epidemic proprotions in the western world. Nearly one million Australians have diabetes mellitus; many of these people will suffer debilitating secondary complications, resulting in significant morbidity and mortality at considerable social and economic cost. Complications include heart attack, stroke, kidney disaease, blindness and limb amputation. There are two forms of diabetes (type I and type 2), and though there are considerable differences in their ....Diabetes mellitus is a disease reaching epidemic proprotions in the western world. Nearly one million Australians have diabetes mellitus; many of these people will suffer debilitating secondary complications, resulting in significant morbidity and mortality at considerable social and economic cost. Complications include heart attack, stroke, kidney disaease, blindness and limb amputation. There are two forms of diabetes (type I and type 2), and though there are considerable differences in their etiology, both forms result in an inability of the body to control blood sugar levels. Beta cells release the hormone insulin, which regulates blood sugar levels. Current knowledge suggests that a loss of beta cell mass is important for both diseases. For type I diabetes the beta cells are destroyed by the immune system. Though for type 2 diabetes the causes are less clear, it is apparent that the beta cells are dying. Our research is focused on understanding the molecular pathways that control beta cell survival and regulate their death. Such knowledge would help us understand the complex processes leading to the development of diabetes. Furthermore, we could use this knowledge in the design of genetic engineering strategies to create 'death-defying' beta cells, as a potential therapeutic strategy for the treatment of diabetes.Read moreRead less