Cellular Mechanisms And Physiological Roles Of GLUT12 Mediated Glucose Transport In Glucose Homeostasis
Funder
National Health and Medical Research Council
Funding Amount
$499,000.00
Summary
Diabetes affects almost one million Australians, although only 50% are aware they have the disease. Type 2 diabetes accounts for about 90% of diabetes and usually occurs after the age of 40. As a leading cause of death, adult blindness, lower limb amputation, kidney failure, stroke and heart attack, diabetes has huge economic and social consequences and has been designated an Australian National Health priority. A clinical feature of Type 2 diabetes is high blood glucose levels. This occurs beca ....Diabetes affects almost one million Australians, although only 50% are aware they have the disease. Type 2 diabetes accounts for about 90% of diabetes and usually occurs after the age of 40. As a leading cause of death, adult blindness, lower limb amputation, kidney failure, stroke and heart attack, diabetes has huge economic and social consequences and has been designated an Australian National Health priority. A clinical feature of Type 2 diabetes is high blood glucose levels. This occurs because insulin does not effectively stimulate the transfer of glucose from the blood into muscle and fat. The reasons for this are not fully understood. Insulin normally works to move glucose transporter (GLUT) proteins to the surface of muscle and fat cells. One GLUT that has been studied extensively in muscle and fat is GLUT4. GLUT4 moves to the cell surface in response to insulin and this response is one of the defects that is known to occur in Type 2 diabetes. Glucose then accumulates in the blood, leading to many of the complications of diabetes. We have discovered a novel glucose transporter, GLUT12, that is also present in muscle and fat. We have shown that GLUT12, like GLUT4, responds to insulin. GLUT12 could therefore be a critical backup for GLUT4. We have also found that GLUT12 responds to glucose itself, suggesting a unique role in controlling blood glucose levels. We will explore how GLUT12 acts in muscle and fat cells to find whether GLUT12 can act as a backup for GLUT4. We will also study GLUT12 in tissue from normal animals and in animals with features of Type 2 diabetes. To determine the role of GLUT12 in maintaining normal blood glucose levels, we will produce mice with an inactive GLUT12 gene. Our research could identify novel ways of increasing GLUT12 activity. The eventual goal will be to find a pharmaceutical compound that can improve glucose transport into muscle, reduce high blood glucose levels and thus the complications of Type 2 diabetes.Read moreRead less
Characterisation Of Notch Asparaginyl Hydroxylation By FIH-1.
Funder
National Health and Medical Research Council
Funding Amount
$307,841.00
Summary
Cells within our body receive numerous signals telling them when to grow, when to turn into another cell type and exactly what type, and even how to respond to situations like low oxygen. These signals and cells response are very important during embryonic development, when these signals cause a single cell to become a complete person, and also in adults. Here in the embryo, and also in adults, stem cells are very important because they can become many different kinds of cells, depending on what ....Cells within our body receive numerous signals telling them when to grow, when to turn into another cell type and exactly what type, and even how to respond to situations like low oxygen. These signals and cells response are very important during embryonic development, when these signals cause a single cell to become a complete person, and also in adults. Here in the embryo, and also in adults, stem cells are very important because they can become many different kinds of cells, depending on what the body needs. When the signals don't work properly, they cause major problems and diseases, from birth defects, to cancer. Notch is an important protein involved in receiving and passing on certain signals, and is found in organisms as diverse as worms and humans. It tells cells, especially stem cells and other similar cells, when and how to change from one type of cell to another. For example, it is very important in the generation of many different types of blood cells from a single precursor cell. Notch has also been implicated in human diseases such as cancer, where signalling goes wrong and cells keep multiplying out of control, and also certain types of heart disease. Another protein, called FIH, is an oxygen sensor that signals to the cell when there is not enough oxygen around. FIH has also been implicated in cancer and heart disease. We have recently found evidence suggesting that FIH can also influence the activity of the Notch proteins. This means that oxygen levels can potentially have an effect on stem cells and other processes controlled by Notch, and may be very important in cancer and other diseases. This project will first confirm the connection between FIH and Notch. There are a number of different Notch proteins, so we will see if this connection works with all of them. It will also try and work out the consequence of this connection is and how important it is. Finally, the likely biological consequences on human diseases, specifically cancer.Read moreRead less
The C-type Lectin, Mincle, Is A Macrophage Receptor For Candida Albicans.
Funder
National Health and Medical Research Council
Funding Amount
$465,210.00
Summary
The yeast Candida albicans is an important opportunistic infection that causes both mucosal and disseminated disease in patients whose innate or adaptive immune responses are impaired Infection and proliferation results in fungal colonisation of the tissues, and a variable degree of tissue damage. The latter is determined both by the virulence properties of the organism and by the genetic makeup of the host. This large, extracellular pathogen is eradicated from the body predominantly by acavenge ....The yeast Candida albicans is an important opportunistic infection that causes both mucosal and disseminated disease in patients whose innate or adaptive immune responses are impaired Infection and proliferation results in fungal colonisation of the tissues, and a variable degree of tissue damage. The latter is determined both by the virulence properties of the organism and by the genetic makeup of the host. This large, extracellular pathogen is eradicated from the body predominantly by acavenger (phagocytic) cells, which are also important in determining the severity of the associated tissue lesions. A phagocytic cell that is central to both innate and adaptive immune responses is the macrophage, which not only takes up and kills the yeast, but also is capable of of killing and digesting it, and presenting the components to cells of the adaptive immune system. This project is based on the postulate that the outcome and severity of infection is determined, at least in part, by the early functional response of the macrophage to the overall virulence properties of the yeast. The response is initiated by interactions with cell-surface receptors, and this study will show that a novel macrophage receptor, Mincle, is an important part of the innate immune response to fungal infections. We have shown that it is associated with differences in susceptibility to yeast infections in inbred mouse strains; it can discriminate between different isolates of the yeast; and it initiates the inflammatory signalling cascade. Our project will define the specific role of this receptor in fungal infection. The results will be important in understanding the basic biology of host resistance, and will offer new opportunities for therapeutic intervention by selectively blocking or modifying different activation pathways.Read moreRead less