Mitochondrial Dysfunction And Pathways Of Cell Death In Drug-induced Liver Injury
Funder
National Health and Medical Research Council
Funding Amount
$301,650.00
Summary
Drugs are an important cause of liver disease that can result in fatal liver damage or require liver transplantation. More than 500 drugs are reported to cause liver disease, but we know almost nothing about how drugs injure the liver. As well as prescribed drugs: panadol, either after self-poisoning or inadvertently taken in too high a dose in someone who is not eating or is taking other medications that interfere with panadol breakdown, is one of most common causes of acute liver failure. Furt ....Drugs are an important cause of liver disease that can result in fatal liver damage or require liver transplantation. More than 500 drugs are reported to cause liver disease, but we know almost nothing about how drugs injure the liver. As well as prescribed drugs: panadol, either after self-poisoning or inadvertently taken in too high a dose in someone who is not eating or is taking other medications that interfere with panadol breakdown, is one of most common causes of acute liver failure. Further, several herbal medicines have been implicated as causing liver disease. This project is designed to help us understand why and how 3 particular drugs damage the liver. We will study panadol, diterpenoids the active ingredients of skullcap, a herbal medicine, and azathioprine (imuran), a drug commonly used to suppress rejection after kidney or liver transplantation which occasionally causes very severe liver disease. Our main hypothesis is that these drugs damage mitochondria, the energy generating structures that form the engine of all living cells. We already know a little about how drug metabolites of panadol and the diterpenoids can damage mitochondria, but no-one has proven that this is the most important way in which they damage the liver. For drugs like azathioprine in which liver damage is rare, we are proposing that genetic defects in the mitochondrial DNA are what could predispose to liver injury. Thus our measurements will include how much mitochondrial DNA damage is caused by the drugs. Panadol, diterpenoids and azathioprine cause liver cell death by differing pathways (called apoptosis and necrosis). There are plausible ways in which mitochondrial damage could start off either (or both) cell death pathways during drug-induced liver injury, and we plan to test these. The new knowledge gained about how drugs damage the liver will be instrumental in allowing us to design new approaches to treat this important problem.Read moreRead less
State-dependence Of Drug Binding To HERG K+ Channels.
Funder
National Health and Medical Research Council
Funding Amount
$397,224.00
Summary
In recent years, it has become apparent that a wide range of prescription drugs can cause inadvertent inhibition of a potassium channel in the heart known as hERG, resulting in an increased risk of cardiac arrhythmias and death. This has prompted the withdrawal from the market of 9 drugs and the introduction of mandatory testing of all drugs for inhibition of hERG channels. In this proposal we seek a molecular explanation for the promiscuity of drug binding to hERG channels
Molecular Basis Of Voltage Dependent-activation Of HERG K+ Channels
Funder
National Health and Medical Research Council
Funding Amount
$439,500.00
Summary
The rhythm of the normal heart beat is controlled by electrical signals mediated by the flow of electrically charged atoms called ions. The flow of ions across heart cell membranes is predominantly mediated by proteins called ion channels that open and close in response to changes in the voltage across the cell membrane. One of these channels, called the HERG channel, has some unusual properties. Most notably, HERG channels open very slowly following an electrical stimulus, so slowly that they d ....The rhythm of the normal heart beat is controlled by electrical signals mediated by the flow of electrically charged atoms called ions. The flow of ions across heart cell membranes is predominantly mediated by proteins called ion channels that open and close in response to changes in the voltage across the cell membrane. One of these channels, called the HERG channel, has some unusual properties. Most notably, HERG channels open very slowly following an electrical stimulus, so slowly that they do not fully open until the end of the cardiac contraction cycle. These channels are therefore particularly well placed to help suppress arrhythmias initiated by premature or ectopic beats. We propose to undertake a detailed investigation into the mechanisms by which HERG channels open and close and to determine why activation of these channels is so slow. These results will provide a greater understanding of how HERG channels work and how the normal activity of HERG channels helps to suppress abnormal heart rhythms.Read moreRead less
The Role Of The Osteoblast In Mediating Glucocorticoid-Induced Metabolic Dysfunction
Funder
National Health and Medical Research Council
Funding Amount
$825,254.00
Summary
Glucocorticoids (GC) exceed most other drugs in terms of numbers of patients treated and indications. Preventing or attenuating the deleterious effects of GC on fuel metabolism is therefore of great clinical significance. Our studies will create new knowledge regarding the mechanisms of GC-induced diabetes and osteoporosis, and will contribute to the development of new approaches that are essential to tackle the pressing medical problem of GC-induced disease.
Clinical Modulation Of The Hyperglycaemic Effect Of A 10-second Sprint In Type 1 Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$567,207.00
Summary
Although regular exercise provides a number of health benefits for individuals with Type 1 diabetes, it increases the risk of hypoglycaemia, which if severe can result in convulsion, coma and irreversible brain damages. Recently, we have made the surprising discovery that it is possible to prevent hypoglycaemia if exercise is combined with one or several short sprints. Our goal is to identify some of the clinical factors likely to interfere with the glucoregulatory benefits of sprinting.
The hERG potassium ion channel is critical for the maintenance of the normal rhythm of the heartbeat. The aim of this study is to map the temporal sequence of the movements of different parts of the hERG K+ channel that regulate the opening and closing of the extracellular gate of the channel. To achieve this, we will use the powerful protein engineering technique of phi-value analysis, a technique that has never before been applied to voltage-gated ion channels.
I am a clinical scientist conducting translational and implementation research to improve diagnosis, management and understanding of airway diseases including asthma, COPD (chronic obstructive pulmonary disease), bronchiectasis and persistent cough.
Generation Of Induced Pluripotent Stem (iPS) Cells And Their Potential Use In Periodontal Regeneration
Funder
National Health and Medical Research Council
Funding Amount
$798,350.00
Summary
Dental diseases affecting the gums (periodontal diseases) are extremely prevalent. The effects of periodontal disease can be particularly severe as loss of support for the teeth leads to loose teeth and severely compromised chewing function. If left untreated, the associated loss of function may necessitate extraction of the teeth. We propose to generate induced pluripotent stem cells from gums and explore whether they can be used to restore periodontal tissues damaged by periodontal disease.