Transcription-based Identification Of Insulin Resistance Subtypes
Funder
National Health and Medical Research Council
Funding Amount
$341,883.00
Summary
A key feature of type 2 diabetes is the failure of metabolic tissues such as muscle and fat to respond to normal levels of insulin. This 'insulin resistance' is caused by a number of mechanisms. We will use cutting-edge technology to identify small sets of genes that define each variety of insulin resistance. These gene sets will be used to diagnose sub-types of insulin resistance and will facilitate the development of personalised therapies to effectively treat individuals with type 2 diabetes.
Reversal Of Diabetes In A Humanised Mouse Using A Clinically Applicable Vector System
Funder
National Health and Medical Research Council
Funding Amount
$842,173.00
Summary
Somatic gene therapy is one of the strategies that is being considered to cure Type I diabetes. Specifically, we wish to engineer liver cells to replace beta cell function. The aim of this project is to design a clinically-applicable protocol for the reversal of diabetes using a recombinant adeno-associated vector that delivers genes to human livers with high efficiency showing long term expression without pathogenicity and immunogenicity following a simple intra-peritoneal injection.
Identification And Characterisation Of A Gene Causing Insulin Hypersecretion In A Mouse Model Of Diabetes Susceptibility
Funder
National Health and Medical Research Council
Funding Amount
$430,320.00
Summary
Diabetes is a disorder primarily characterised by the inability to produce and secrete the pancreatic hormone insulin, which regulates plasma sugar levels. This results in increased sugar levels which cause diabetic complications such as retinopathy and nephropathy. The inability to produce and secrete insulin is due to both defects in function as well as a reduction in pancreatic beta cells. Paradoxically it has been shown that some patients who are at risk of develping diabetes actually secret ....Diabetes is a disorder primarily characterised by the inability to produce and secrete the pancreatic hormone insulin, which regulates plasma sugar levels. This results in increased sugar levels which cause diabetic complications such as retinopathy and nephropathy. The inability to produce and secrete insulin is due to both defects in function as well as a reduction in pancreatic beta cells. Paradoxically it has been shown that some patients who are at risk of develping diabetes actually secrete more insulin than normal. Furthermore it has been suggested that this increase in insulin secretion actually may be associated with the decreased production and secretion of insulin characteristic of diabetes. The DBA-2 mouse is a model of reduced insulin production and secretion when exposed to high sugar levels or diabetes. However we have shown that in the normal non-stressed state DBA-2 mice actually secrete more insulin than normal and that this occurs from a very early age, suggesting that this trait is inherited. We have subsequently performed genetic studies and have identified a segment of DNA containing 10 genes associated with increased insulin secretion in DBA-2 mice. The level of one of these genes we have called Hip1 is increased 5-fold in DBA-2 mice, providing a candidate gene for increased insulin secretion in this model of diabetes susceptibility. However, whether Hip1 is also responsible for reduced insulin production and secretion in the DBA-2 mouse is not known. Therefore the overall hypothesis of this project is that the gene Hip1 which is associated with increased insulin secretion is also responsible for reduced insulin production and secretion when DBA-2 mice are exposed to high sugar or obesity. Determining why Hip1 is increased and whether it results in diabetes in DBA-2 mice may provide a reasonable candidate for the development of therapeutic interventions which may prevent the progression of diabetes in some patients.Read moreRead less
Investigation Of The Genetic Basis Of Insulin Hypersecretion In A Mouse Model Of Pancreatic Islet Failure
Funder
National Health and Medical Research Council
Funding Amount
$406,980.00
Summary
Type 2 diabetes is a chronic disease that is associated with blindness, kidney failure, heart attacks and stroke and these are secondary to high blood sugar levels. Thus, determining the cause of high blood sugar levels in type 2 diabetes will lead to better management of the disease and ease the financial burden on the public health system. High blood sugar in type 2 diabetes results from the inability of the body to secrete enough insulin. Insulin is the main hormone that lowers blood sugar le ....Type 2 diabetes is a chronic disease that is associated with blindness, kidney failure, heart attacks and stroke and these are secondary to high blood sugar levels. Thus, determining the cause of high blood sugar levels in type 2 diabetes will lead to better management of the disease and ease the financial burden on the public health system. High blood sugar in type 2 diabetes results from the inability of the body to secrete enough insulin. Insulin is the main hormone that lowers blood sugar levels and is produced by the pancreas. The reason for reduced insulin secretion in type 2 diabetes is not known. Paradoxically, it has been shown that some people who are at an increased risk of developing diabetes (eg people with obesity or a family history of diabetes) secrete more insulin than normal. It is not clear why this is, but a few studies have suggested that reducing insulin secretion in these circumstances can protect the pancreas and preserve its ability to secrete the appropriate amount of insulin. The DBA-2 is a mouse strain that like humans with type 2 diabetes, its pancreas can also fail to secrete the appropriate amount of insulin and under these circumstances becomes diabetic. Furthermore our laboratory has generated evidence that shows that like people who are at risk of diabetes, DBA-2 mice in fact secrete more insulin prior to becoming diabetic. Whether the cause of this increased insulin secretion is linked to the eventual reduction of secretion is not known. The aim of this study is to identify the gene that causes increased insulin secretion in the DBA-2 mouse. Furthermore, genetically manipulated animals will be produced that contain only this gene to determine its effect on insulin secretion. Should the identification of this gene be related to the eventual failure of the pancreas to secrete enough insulin, then it would provide a target for drug therapy to correct insulin levels and therefore reduce blood sugar levels.Read moreRead less
Defining Factors That Contribute To Individual Diversity In The Diet-health Axis
Funder
National Health and Medical Research Council
Funding Amount
$1,668,059.00
Summary
There is a complex interplay between nutrition and genetics such that one diet maybe good for some but not for others depending on genetic makeup. Preliminary experiments in flies and mice support this. We found that for some flies, diets high in fat are harmful resulting in short life but certain flies resist the harmful effects of fat and live a longer lives. We propose to unravel the gene-environment interaction and determine which genes might lead to optimal health outcomes on certain diets.