A Genome-wide Search For Genes Underlying The Developmental Origins Of Health And Disease
Funder
National Health and Medical Research Council
Funding Amount
$1,022,552.00
Summary
Epidemic rises in the incidence of many chronic diseases such as obesity, type 2 diabetes, hypertension, coronary artery disease and mental illness have occurred in Australia over the last two decades. Antenatal, early life and childhood factors have been consistently associated with the development of such diseases. We propose to conduct a genome-wide scan in an exceptional longitudinal birth cohort in order to identify the genetic mechanisms linking early life event and adult disease.
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
$285,990.00
Summary
Friedreich's ataxia (FA) is due to the lack of a protein known as frataxin. Recent studies using Baker's yeast have shown that the deletion of frataxin results in the accumulation of toxic iron in the mitochondrion. More recently, a variety of studies have shown that FA patients have iron loading within their cells. The iron build-up may cause severe damage. At present, the role of frataxin in mammalian mitochondrial iron metabolism is unknown. Our preliminary studies demonstrate that frataxin i ....Friedreich's ataxia (FA) is due to the lack of a protein known as frataxin. Recent studies using Baker's yeast have shown that the deletion of frataxin results in the accumulation of toxic iron in the mitochondrion. More recently, a variety of studies have shown that FA patients have iron loading within their cells. The iron build-up may cause severe damage. At present, the role of frataxin in mammalian mitochondrial iron metabolism is unknown. Our preliminary studies demonstrate that frataxin is down-regulated by either erythroid differentiation or the haem precursor protoporphyrin IX (Becker and Richardson, submitted). These data strongly suggest a role for frataxin in iron metabolism. In the present study we will continue to assess if frataxin plays a role in the way cells handle iron. Using a unique model of mitochondrial iron overload developed in my lab (Richardson et al. (1996) BLOOD 87:3477), we will extensively investigate the iron metabolism of the mitochondrion in order to determine the function of frataxin and its role in Friedreich's ataxia. In addition, we have developed a series of new drugs known as iron chelators that can enter the mitochondrion due to their high lipid solubility (Becker and Richardson 1999 J. Lab. Clin. Med. 134:510). These latter drugs are far more effective than the chelator currently used to treat iron overload, desferrioxamine (DFO). Indeed, our chelators have been designed to result in high iron chelation efficacy but low toxicity (see Becker and Richardson, 1999). This exciting research may be crucial in understanding the development of FA and in creating new therapies such as the use of iron chelators.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
Enhancing Peripheral Clearance Of Beta Amyloid As A Treatment For Alzheimers Disease
Funder
National Health and Medical Research Council
Funding Amount
$548,681.00
Summary
Amyloid-beta (abeta) accumulation in the brain is a key step in the development of Alzheimer's disease, with potential therapies focusing on its clearance. Compounds that bind abeta in blood have been shown to alter brain abeta levels. We will assess the efficacy of a novel abeta-binding peptide to promote peripheral clearance of brain-derived abeta in a mouse model of AD. Such a drug would be effective in sporadic AD, where the efflux transport, clearance and degradation systems are defective.
Dissecting The Pseudoexfoliation Syndrome With Complementary Genetic, Proteomic And Biophysical Strategies
Funder
National Health and Medical Research Council
Funding Amount
$490,352.00
Summary
Pseudoexfoliation syndrome (PEX) is an eye condition in which flaky material deposits in the eye, greatly increasing the risk of cataract and glaucoma which can lead to blindness. PEX is also associated with heart disease, strokes and aneurysms. Cataract surgery in PEX patients has a higher rate of complications. In this project we will determine the nature of PEX material and why it forms. This knowlege will facilitate better diagnosis and treatment of PEX preventing associated blindness.
Determinant Spreading And The Role Of The MHC Class II Region In Systemic And Organ-specific Autoimmunity
Funder
National Health and Medical Research Council
Funding Amount
$140,570.00
Summary
Autoimmune diseases are among the most important group of disorders affecting the adult population. In these diseases the immune system damages organs and tissues producing widespread pathology (systemic autoimmunity such as Lupus erythematosus) or localised disease (organ-specific autoimmunity such as insulin dependent diabetes). We understand very little about how and why the immune system attacks the body's own tissues. This study examines how antibodies and T lymphocytes are formed against c ....Autoimmune diseases are among the most important group of disorders affecting the adult population. In these diseases the immune system damages organs and tissues producing widespread pathology (systemic autoimmunity such as Lupus erythematosus) or localised disease (organ-specific autoimmunity such as insulin dependent diabetes). We understand very little about how and why the immune system attacks the body's own tissues. This study examines how antibodies and T lymphocytes are formed against components located inside cells of the body. The study involves genetically modifying mice by introducing key human genes which influence the development of autoimmunity. In this way the role of these human genes can be examined experimentally without having to work exclusively on patients. We also hope that these mice might be important in creating new models of celiac disease and insulin dependent diabetes. The proposed experiments should tell us how these genes contribute to the development of autoimmune disease. This understanding could be relevant devising treatments and interventions to prevent autoimmune diseases.Read moreRead less
Development Of Iron Chelators For The Treatment Of Friedreichs Ataxia And The Role Of Frataxin In Iron Metabolism
Funder
National Health and Medical Research Council
Funding Amount
$550,987.00
Summary
Friedreich's ataxia (FA) is a neuro- and cardio-degenerative disease where there is an accumulation of toxic Fe in the mitochondrion. Excitingly, work from our current NHMRC grant showed iron plays a significant role in FA pathology. Importantly, we developed new drugs (Fe chelators) which rescue the cardiac pathology of FA in an animal model. Studies will now assess if our drugs prevent the neurodegeneration of FA in another animal model. This work could lead to novel therapies for FA.
Effects Of Latrepirdine On Beta Amyloid Clearance, Aggregation And Neurodegeneration In Alzheimer�s Disease
Funder
National Health and Medical Research Council
Funding Amount
$512,647.00
Summary
Alzheimer's disease (AD) is becoming more common with our growing aged population and currently no treatment exists that halts disease progress. The increasing health costs of AD underscore the need for development of any treatment that will slow or halt AD pathogenesis. By understanding the mechanisms of action of a drug [latrepirdine] that has recently shown some promise in phase II clinical trials, related drugs that are more specific and potent will be developed.
Functional Effects Of Polymorphic Variation Of The Aromatase (CYP19) Gene On Enzyme Activity:relationship To Disease
Funder
National Health and Medical Research Council
Funding Amount
$237,708.00
Summary
After menopause, oestrogen synthesis changes from an ovarian to an adipose source by concersion of androgens to estrogens, a process catalyzed by aromatase, the product of the CYP19 gene. We will generate mutants of the CYP19 gene that we have previously found in humans by site-directed mutagenesis and observe the effects of these mutants on aromatase function. This research will help with diagnosis and treatment of breast and other cancers and osteoporosis in humans .
Unravelling The Mechanism Of MHC Class-I Associated Drug Hypersensitivities
Funder
National Health and Medical Research Council
Funding Amount
$566,308.00
Summary
Some drugs cause adverse reactions that are life threatening. We think these reactions are mediated by killer T cells as they are genetically controlled by immune response genes that normally guide immunity to microbes. We will study immune reactions to the drug abacavir, used to treat HIV (AIDS); allopurinol used to prevent gout and carbamazepine, used to treat epilepsy. The study may also help devise better treatments for patients who experience severe forms of these reactions.