Interactions Between Advanced Glycation And Oxidative Stress In Diabetic Renal And Cardiac Complications
Funder
National Health and Medical Research Council
Funding Amount
$431,700.00
Summary
Kidney and heart disease are serious complications of diabetes. These complications are the major cause of disability and premature death in the western world. Studies from our group and others have shown that diabetic complications appear to be a consequence of a number of different processes. These pathways include a sugar dependent pathway of irreversible interactions between proteins such as collagen and sugar known as advanced glycation. The process of advanced glycation alters the body's a ....Kidney and heart disease are serious complications of diabetes. These complications are the major cause of disability and premature death in the western world. Studies from our group and others have shown that diabetic complications appear to be a consequence of a number of different processes. These pathways include a sugar dependent pathway of irreversible interactions between proteins such as collagen and sugar known as advanced glycation. The process of advanced glycation alters the body's ability to renew these protein, hence causing accelration of the ageing process. In fact, it is estimated that this process occurs almost fifty times faster in diabetes. These sticky complexes accumulate in tissues causing disruption ot the normal tissue structure. Our group has a drug which can act as scissors and cut the sticky sugar off the proteins allowing it to be turned over. Unfortunately this does not fix all of the damage. These AGE molecules are involved in a number of other harmful processes including the production of toxic oxygen derived molecules which are harmful byproducts of diabetes. While these oxygen 'radicals' have been implicated in heart attack and stroke their source has remained a mystery in diabetes. Previously, the only way to remove these molecules was to mop them up with antioxidants such as Vitamin E. Antioxidants work slowly and so some damage is already done before they 'detoxify' these oxygen radicals. We propose to use combinations of medicines to see if we can achieve more effective protection against these processes in experimental diabetes. This may provide new therapies for threatment of kidney and heart disease in diabetes.Read moreRead less
Sex Differences In The Mechanisms By Which Stress Inhibits The Secretion And Actions Of GnRH
Funder
National Health and Medical Research Council
Funding Amount
$408,055.00
Summary
It is well known that stress can impair reproduction in humans and animals but it is not understood how this occurs. Consequently there are no therapies available to overcome the detrimental effects of stress on reproduction. Stress can take many forms, such as psychological stress, surgical trauma, strenuous exercise, undernutrition, all of which may inhibit reproduction. We now know that males and females respond differently to stress and we have shown that stress is also likely to have differ ....It is well known that stress can impair reproduction in humans and animals but it is not understood how this occurs. Consequently there are no therapies available to overcome the detrimental effects of stress on reproduction. Stress can take many forms, such as psychological stress, surgical trauma, strenuous exercise, undernutrition, all of which may inhibit reproduction. We now know that males and females respond differently to stress and we have shown that stress is also likely to have different effects on reproduction in males and females. In this project we aim to determine how stress impairs reproduction in males and females. A major effect of stress appears to be to inhibit the secretion of a substance produced by the brain that is necessary for the regulation of reproduction. This substance is called gonadotrophin releasing hormone (GnRH) and it acts on a small gland at the base of the brain to cause the release of hormones that are essential for reproduction in both males and females. It is also possible that stress may inhibit the actions of GnRH. Our research suggests that there may be differences between males and females in the extent to which stress inhibits the secretion of GnRH from the brain and its actions to cause the release of other reproductive hormones. In this project we will determine how stress acts in the brain to affect the secretion and actions of GnRH in males and females. Our research will make a major contribution to our knowledge of the way that stress inhibits reproduction in males and females. This information is essential in order to develop specific remedies to overcome reproductive disorders caused by stress and to improve reproductive health in both sexes.Read moreRead less
Investigating The Physiological And Clinical Differences In Weight Loss In Obese Subjects With And Without Diabetes.
Funder
National Health and Medical Research Council
Funding Amount
$101,726.00
Summary
Obesity and type 2 diabetes are linked by the production of inflammatory factors in the body. These factors seem to link weight gain, especially around the abdomen, not only with insulin resistance, the precursor to diabetes, but also independently with the development with heart and kidney disease and reduced fertility. This study will investigate the effect of dieting and weight loss on inflammation and the function of the heart and other organs in obese people with and without diabetes.
Insulin-like Growth Factor Binding Protein-3 (IGFBP-3) Sensitivity And Signalling In Breast Cancer
Funder
National Health and Medical Research Council
Funding Amount
$414,343.00
Summary
The growth of all tissues in the body depends on many growth factors, hormones and other proteins which work together to control cell division. Some of these factors stimulate the division of the cells which make up the body tissues, and some inhibit it, so that a balance of these stimulators and inhibitors ensures that tissues do not grow too fast, or too large. The development of breast cancer and the growth of breast tumours is thought to be due to uncontrolled or faulty actions of the protei ....The growth of all tissues in the body depends on many growth factors, hormones and other proteins which work together to control cell division. Some of these factors stimulate the division of the cells which make up the body tissues, and some inhibit it, so that a balance of these stimulators and inhibitors ensures that tissues do not grow too fast, or too large. The development of breast cancer and the growth of breast tumours is thought to be due to uncontrolled or faulty actions of the proteins and hormones which regulate the way breast cells multiply. One protein which normally regulates the division of breast cells is IGFBP-3. We have found that in some breast cancer cells, IGFBP-3 is no longer able to inhibit cell division, and this may lead to tumour growth and invasion of other tissues. We are interested in finding out how IGFBP-3 normally controls breast cell proliferation, and why some breast cancers are resistant to IGFBP-3. To do this, we will use normal breast cells in culture to examine how IGFBP-3 interacts with other cellular factors to prevent cell division. We will then look at whether the breast cancer cells have changed so that they are no longer able to recognise IGFBP-3 as an inhibitory protein. This may be because of changes in the way IGFBP-3 binds to the breast cancer cell, or because of changes in the way it interacts with other proteins in the cell. Because IGFBP-3 is made by normal and breast cancer cells, we will also study whether the IGFBP-3 being made by breast cancer cells is normal, or if it changed in some way that makes it inactive. By understanding why some breast cancers are not inhibited by IGFBP-3, we will be able to design new and better methods of preventing, detecting and treating the growth of all breast tumours.Read moreRead less
Structural And Functional Investigation Into The Cooperation Of IGF And Vitronectin-binding Receptors In Cell Migration
Funder
National Health and Medical Research Council
Funding Amount
$239,250.00
Summary
Breast cancer is the most commonly diagnosed form of cancer in Australian women, accounting for 26% of diagnosed cancers and 21% of cancer deaths among women. One in fourteen Australian and one in nine women worldwide will develop breast cancer in their lifetime. Significantly, approximately one in four of those diagnosed will die from their disease. The primary factor that determines survival is early diagnosis and treatment. Indeed, the primary tumour itself rarely causes death. Rather, the di ....Breast cancer is the most commonly diagnosed form of cancer in Australian women, accounting for 26% of diagnosed cancers and 21% of cancer deaths among women. One in fourteen Australian and one in nine women worldwide will develop breast cancer in their lifetime. Significantly, approximately one in four of those diagnosed will die from their disease. The primary factor that determines survival is early diagnosis and treatment. Indeed, the primary tumour itself rarely causes death. Rather, the dissemination of tumour cells to remote sites and the establishment of secondary tumours in critical sites in the body is the major mechanism of mortality. An understanding of the processes that lead to the establishment of secondary tumour bodies and strategies to halt the spread of cancer beyond the primary site are therefore highly valuable. Two factors thought to be pivotal in breast cancer metastasis are altered interactions with the microenvironment surrounding cells and exposure to increased levels of hormones and growth factors, such as the insulin-like growth factors (IGFs). We have recently found that IGFs form complexes with a protein called vitronectin, found in the microenvironment, and these complexes can stimulate increased migration of breast cancer cells. This project will examine the interaction of IGF and VN in stimulating cell migration and in particular, aims to identify the genes involved in the enhanced cell migration. In addition we will examine how the IGF:vitronectin complexes form and how these in turn interact with receptors on the surface of the cell. The data obtained will provide critical fundamental information that is necessary to develop targeted therapies for the treatment and control of breast cancer.Read moreRead less
Mineralocorticoid Receptor Co-regulator Recruitment Determines Ligand Specific Signalling.
Funder
National Health and Medical Research Council
Funding Amount
$491,530.00
Summary
Heart disease is a major cause of death and economic burden in Australia and throughout the world. The steroid hormone aldosterone controls salt and water balance,blood pressure and hasa significant role in heart failure. Although drugs that block the aldosterone receptor significantly help patients with heart failure, their use is limited by side effects. This work will identify the profile of proteins that promote aldosterone effects and enable the development of heart-specific blockers.
Steroid hormones, such as oestrogen and cortisol, act in the body by binding a family of proteins (nuclear receptors) that bind directly to the DNA to regulate genes. The mechanisms underlying this process are complex and involve recruitment of additional molecules or coactivators to improve efficiency. Recently a novel coactivator was identified termed SRA, which remarkably is never made into protein in cells, rather exerting its effects as a RNA. We have identified a novel family of proteins t ....Steroid hormones, such as oestrogen and cortisol, act in the body by binding a family of proteins (nuclear receptors) that bind directly to the DNA to regulate genes. The mechanisms underlying this process are complex and involve recruitment of additional molecules or coactivators to improve efficiency. Recently a novel coactivator was identified termed SRA, which remarkably is never made into protein in cells, rather exerting its effects as a RNA. We have identified a novel family of proteins that bind to SRA in cancer cells, and may well play a critical role in regulating how SRA modulates genes. This project seeks to understand how this family interacts with SRA, the functional effects on breast cancer cells, and the detailed 3-dimensional structure of the family members coupled with SRA. This work will provide novel insight into how SRA regulates steroid hormone action, and may create new potential avenues for developing therapeutics in breast cancer.Read moreRead less
Role Of IGF Binding Protein-3 (IGFBP-3) And IGFBP-5 As Modulators Of Nuclear Hormone Signalling
Funder
National Health and Medical Research Council
Funding Amount
$465,750.00
Summary
The insulin-like growth factors are small proteins involved in the growth of most tissues. Their actions are regulated by binding to larger proteins (known as IGFBPs) in the bloodstream and outside the cell. However, some IGFBPs are also found inside cells, where they seem to carry out other functions. We believe that two of these binding proteins, IGFBP-3 and IGFBP-5, change the way cells respond to vitamin A and vitamin D. These two vitamins are important in cell growth and in the way certain ....The insulin-like growth factors are small proteins involved in the growth of most tissues. Their actions are regulated by binding to larger proteins (known as IGFBPs) in the bloodstream and outside the cell. However, some IGFBPs are also found inside cells, where they seem to carry out other functions. We believe that two of these binding proteins, IGFBP-3 and IGFBP-5, change the way cells respond to vitamin A and vitamin D. These two vitamins are important in cell growth and in the way certain cells perform specialised functions. In test-tube experiments, IGFBP-3 and IGFBP-5 interact directly with the receptors that regulate the effects of these hormones. If the same thing happens inside the cell, IGFBP-3 and IGFBP-5 could change the way these receptors respond to signals from outside the cell. We will investigate what effect these IGFBPs have in living cells and in whole animals and how this may relate to human disease. If we are able to understand how IGFBP-3 and IGFBP-5 affect the way cells respond to vitamin A and D, then we may be able to develop new ways to treat certain human diseases.Read moreRead less