The Role Of Capsid Protein Nucleolar Localisation In Chikungunya Virus: Implications For Vaccine Development
Funder
National Health and Medical Research Council
Funding Amount
$520,520.00
Summary
Chikungunya virus (CHIKV) is a globally widespread mosquito-borne alphavirus capable of causing considerable human morbidity and mortality. With no CHIKV vaccine or antiviral available this proposal aims to develop a live attenuated CHIKV vaccine, rationally designed by investigating the host cell nucleolar trafficking of CHIKV capsid protein. This vaccine has the potential to provide cross-protection against additional arthritogenic alphaviruses endemic to Australia such as Ross River virus.
Novel Insights Into The Pathobiology Of Alphavirus Infections
Funder
National Health and Medical Research Council
Funding Amount
$827,660.00
Summary
Infections with mosquito-borne viruses are increasing at an alarming rate worldwide. Ross River virus is endemic in parts of Australia, PNG and Pacific islands, while chikungunya virus is distributed globally and causes recurrent pandemics that involve millions of people. These viruses cause severe musculoskeletal disease for several months after infection. This project aims to establish how these viruses interact with the human host to cause disease and may provide a basis for new treatments.
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
A National Population-based Study Of Rheumatic Heart Disease In Pregnancy
Funder
National Health and Medical Research Council
Funding Amount
$877,826.00
Summary
Whilst overall a rare disease, Indigenous peoples have disproportionately high rates of rheumatic heart disease (RHD). This study explores the prevalence and distribution of RHD in pregnancy in Australia and New Zealand. It details current management, diagnostic and referral process and risk factors. Key attributes of culturally safe models of care for RHD in pregnancy are explored, particularly as they relate to Indigenous women. Findings will inform policy, guidelines and education resources.
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.
Arbovirus Activation And Modulation Of NLRP3 Inflammasome
Funder
National Health and Medical Research Council
Funding Amount
$779,720.00
Summary
This project aims to establish how mosquito borne viruses such as Ross River and dengue viruses interacts with the human host to cause disease, including how the virus evades the host’s immune response to persist and cause disease for prolonged periods. Knowing how differences in the virus and the host’s immune system interplay to cause asymptomatic to severely disabling disease will assist in devising new treatments and prevention programs to lessen the impact of these diseases in Australia.
Mosquito-borne alphaviruses such as Ross River and chikungunya viruses cause widespread epidemics and exert extreme pressure on the public health systems of affected regions. Alphaviruses spreads to joints and triggers a severe disease in those affected. There are no effective treatments or vaccines. The project will investigate virus-host interaction at the bite site. The outcome will be new knowledge to treat infection at the mosquito bite site to prevent joint disease.
Glycotherapeutics; A New Class Of Treatment For Alphavirus-induced Musculoskeletal Disease
Funder
National Health and Medical Research Council
Funding Amount
$449,868.00
Summary
The hallmark of alphavirus disease is crippling pain and joint arthritis, which often has an extended duration. Currently there is no licenced specific treatment for alphavirus disease and the increasing spread of infection highlights an urgent need for therapeutic intervention strategies. This grant looks at the potential of pentosan polysulfate as a promising drug-repurposing candidate for the treatment of alphavirus-induced arthritis.
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