Role Of Transition Metal Ions And Redox Activity In The Development Of Atherosclerotic Plaques
Funder
National Health and Medical Research Council
Funding Amount
$196,018.00
Summary
Metal ions such as iron and copper have been reproted to be present in the lesions present in diseased human arteries and it has been suggested that these metal ions contribute to the development of atherosclerosis (hardening of the arteries) via their ability to catalyse the formation of highly reactive molecualr fragments called free radicals. Though metal ions are known to catalyse such reactions in test-tube experiments, both the presence of metal ions in diseased arteries and their ability ....Metal ions such as iron and copper have been reproted to be present in the lesions present in diseased human arteries and it has been suggested that these metal ions contribute to the development of atherosclerosis (hardening of the arteries) via their ability to catalyse the formation of highly reactive molecualr fragments called free radicals. Though metal ions are known to catalyse such reactions in test-tube experiments, both the presence of metal ions in diseased arteries and their ability to generate free radicals is controversial. This study will employ a novel, minimally-invasive, technique to assess the nature and quantity of metal ions present in well-defined human and animal lesions at different stages of lesion development. The ability of these metal ions to catalyse free radical formation from components present in the artery wall will also be assessed. The release of these metal ions from the artery wall to added organic molecules will be assessed as this might minimise their potential to cause damage, and provide a possible therapeutic strategy. These studies will therefore provide valuable information as to the significance and role of reactive metal ions in the development of human artery disease and the possible prevention, or minimisation, of such processes.Read moreRead less
Mitochondrial Iron Overload And Friedreich's Ataxia: The Role Of Frataxin In Iron And Haem Metabolism
Funder
National Health and Medical Research Council
Funding Amount
$606,000.00
Summary
Friedreich's ataxia (FA) is due to the lack of a protein known as frataxin. A variety of studies using Baker's yeast and conditional frataxin knockout (KO) mice have shown that deletion of frataxin leads to the accumulation of toxic iron in their mitochondrion. More recently, a variety of studies have shown that FA patients have iron-loading within their mitochondrion. Iron in the highly redox active environment of the mitochondrion could contribute to the generation of cytotoxic radicals that c ....Friedreich's ataxia (FA) is due to the lack of a protein known as frataxin. A variety of studies using Baker's yeast and conditional frataxin knockout (KO) mice have shown that deletion of frataxin leads to the accumulation of toxic iron in their mitochondrion. More recently, a variety of studies have shown that FA patients have iron-loading within their mitochondrion. Iron in the highly redox active environment of the mitochondrion could contribute to the generation of cytotoxic radicals that cause severe damage. Further, cells deficient in frataxin are sensitive to oxidant stress and Fe chelators rescue oxidant-mediated death of cells from FA patients. Indeed, free radical scavengers have shown to be of use in the treatment of this disease. Studies in DR's lab during this NHMRC grant have shown that frataxin is down-regulated by erythroid differentiation or the haem precursor, protoporphyrin IX (BLOOD 2002;99:3813-22). These data indicate a role for frataxin in Fe metabolism and the pathogenesis of FA. In this study we will continue to examine the role of frataxin in the way cells handle Fe using experimental models developed under the current NHMRC grant. These include transfected cell lines with low frataxin expression generated using an expression vector containing anti-sense frataxin cDNA. Further we obtained the frataxin conditional KO mouse and generated a breeding colony. These animals display many of the pathological features of FA and are the best current model of the disease. Indeed, they will be critical for assessing the role of frataxin in Fe metabolism and as a model to test the ability of Fe-binding drugs to prevent the pathology observed. We designed lipid-soluble chelators that can enter the mitochondrion to bind Fe (Biochim Biophys Acta 2001;1536:133-140) and these ligands will be tested to prevent disease progression in the KO mice. This exciting research is crucial for understanding the pathogenesis of FA and in creating new therapies.Read moreRead less
External Therapeutic Device To Support Rehabilitation Of The Hand Following Trauma Or Surgery
Funder
National Health and Medical Research Council
Funding Amount
$175,000.00
Summary
The loss of hand function will affect every aspect of an individual’s life. This includes the ability to feed and care for themselves and the ability to work and participate in family life. For people recovering from problems such as trauma, burns or surgery affecting the hand, careful management of hand rehabilitation can influence the outcome for the patient significantly. In order to reduce the possibility of mobility difficulties occurring, including loss of joint range of motion, muscle and ....The loss of hand function will affect every aspect of an individual’s life. This includes the ability to feed and care for themselves and the ability to work and participate in family life. For people recovering from problems such as trauma, burns or surgery affecting the hand, careful management of hand rehabilitation can influence the outcome for the patient significantly. In order to reduce the possibility of mobility difficulties occurring, including loss of joint range of motion, muscle and tendon sheath adhesions or non-functional scar tissue formation, continuous passive motion (CPM) is often indicated. Additionally, for people with reduced mobility of the hand due to upper limb paralysis, such as those with cervical spinal cord injury, stroke, cerebral palsy or peripheral nerve injury, disregard for management of the maintenance of the joint range of motion of the effected hand will result in contracture and limited joint range of motion. Such syndromes will reduce hand function, which is already limited by paralysis, and will negatively affect potential outcomes for aggressive rehabilitation techniques, such as tendon transfer surgery and functional neuromuscular stimulation. Therefore, in such cases, CPM is also indicated. Current devices applying CPM have shown to be effective in minimising the syndromes indicated above and these results are summarised in the Background and Research Plan attached to this proposal. Unfortunately, the use of such devices is not always prescribed by clinicians. This is due, mainly, to the limitations of these devices that are in the marketplace. These limitations include lack of secure finger placement, lack of portability, the inability to provide specialised therapy to specific joints and inflexible programming. This proposal introduces an improved device to be developed and these improvements form the proposal aims below. Given such an improved device, which can overcome many of the problems with current CPM machines, it is likely that that the clinical application of CPM will achieve the greater degree of prescription and application in hand rehabilitation. These improvements should overcome the clinical reticence to use these devices and restore a balance by increasing their use to the level that the scientific literature indicates they should have. The overall aim of the proposal is to take the device to a stage where it is ready for clinical trial.Read moreRead less
Heparin Induced Thrombocytopenia (HIT): Further Characterization Of Disease Mechanism Will Improve Patient Treatment
Funder
National Health and Medical Research Council
Funding Amount
$456,484.00
Summary
Thrombus formation occurs as a side effect of heparin treatment in many patients. This condition is called Heparin Induced Thrombocytopenia (HIT). The clots may be stabilised by secretions from cells called neutrophils. In this project we will study this possibility using a mouse model of HIT and will explore therapeutic approaches to inhibit clot stabilisation.
The critical role of the class III histone deacetylase SIRT2 in stabilizing N-Myc oncoprotein. Cancer is the commonest cause of death from disease in children. Neuroblastoma is the commonest solid tumor in early childhood. This project will investigate the critical roles of SIRT2 protein in increasing the expression of N-Myc oncoprotein and consequently inducing neuroblastoma, and SIRT2 inhibitors as anticancer agents.
Signalling Networks As Targets For Antibody Therapy In Glioma.
Funder
National Health and Medical Research Council
Funding Amount
$526,683.00
Summary
Antibodies are a major component of the bodies immune system that bind (i.e. stick) to foreign substances such as viruses. Once bound, these antibodies can activate other parts of the immune system, which help destroy the foreign substance. Analogous to the situation above, a number of institutions are testing antibodies that bind to cancer cells, in order to determine if they are able to destroy these cells. It is also possible to generate antibodies that bind to receptors on the surface of can ....Antibodies are a major component of the bodies immune system that bind (i.e. stick) to foreign substances such as viruses. Once bound, these antibodies can activate other parts of the immune system, which help destroy the foreign substance. Analogous to the situation above, a number of institutions are testing antibodies that bind to cancer cells, in order to determine if they are able to destroy these cells. It is also possible to generate antibodies that bind to receptors on the surface of cancer cells and block their function. If you target a receptor critical to the growth or survival of a cancer cell in this way, then swtiching-off this signal may inhibit tumor growth. In this proposal we plan to test a panel antibodies that recognize receptors important to the growth of brain cancer. Two of these antibodies have been generated and the other two will be made as part of this proposal. A key aspect of this proposal will be testing these antibodies in combination to determine how many receptors need to be targeted in order to get complete tumor regressions in animal models. Overall this work will help us identify new therapeutic strategies for the treatment of brain cancer. Finally, we will also analyze the way different receptors interact together in brain cancer cells.Read moreRead less