Show simple item record

dc.contributor.advisorPerkins, Tony
dc.contributor.authorVenardos, Kylie M
dc.date.accessioned2018-01-23T02:17:01Z
dc.date.available2018-01-23T02:17:01Z
dc.date.issued2005
dc.identifier.doi10.25904/1912/3596
dc.identifier.urihttp://hdl.handle.net/10072/365301
dc.description.abstractCoronary heart disease remains the greatest killer of Australian's, and given our ageing population, along with increasing risk factors, it is predicted to become an even more significant problem worldwide over the next 20 years. Reperfusion, without doubt is the most effective treatment for ischemic myocardium. However, this produces deleterious effects upon cells, and depending on the severity, may ultimately lead to cell death. While the pathogenesis of ischemia-reperfusion is not completely understood, there is considerable evidence implicating reactive oxygen species (ROS) as an initial cause of the injury. ROS formed during oxidative stress can initiate lipid peroxidation, oxidize proteins to inactive states and cause DNA strand breaks, all potentially damaging to normal cellular function. ROS have been shown to be generated following routine clinical procedures such as coronary bypass surgery and thrombolysis, due to the unavoidable episode of ischemiareperfusion. Furthermore, they have been associated with poor cardiac recovery post-ischemia, with recent studies supporting a role for them in infarction, necrosis, apoptosis, arrhythmogenesis and endothelial dysfunction following ischemia-reperfusion. In normal physiological condition, ROS production is usually homeostatically controlled by endogenous free radical scavengers such as SOD, catalase, and the glutathione peroxidase and thioredoxin reductase systems. Targeting the generation of ROS with various antioxidants has been shown to reduce injury following oxidative stress, and improve recovery from ischemia-reperfusion injury. This thesis investigates the role of myocardial antioxidant enzymes in ischemiareperfusion injury, particularly the glutathione peroxidase (GPX) and the thioredoxin reductase (TxnRed) systems. GPX and TxnRed are selenocysteine dependent enzymes, and their activity is known to be dependent upon an adequate supply of dietary selenium and selenocysteine. In mammalian cells, the generation of selenocysteine occurs during amino acid biosynthesis and the degree of selenium (Se) incorporation into the cysteine residue is concentration dependent. Previous studies have found that up-regulation of these systems is cardioprotective and down-regulation is detrimental following ischemia-reperfusion. This thesis attempts to extend these observations by increasing not only our understanding of the roles of myocardial antioxidant enzymes in ischemia-reperfusion injury, but also the effect of dietary selenium on these systems. Furthermore, it investigates the effects of ischemia, reperfusion, and ageing on myocardial antioxidant enzymes.
dc.languageEnglish
dc.publisherGriffith University
dc.publisher.placeBrisbane
dc.rights.copyrightThe author owns the copyright in this thesis, unless stated otherwise.
dc.subject.keywordsCoronary heart disease
dc.subject.keywordsmyocardial antoxidant
dc.subject.keywordsischemic myocardium
dc.subject.keywordsreactive oxygen species
dc.subject.keywordsischemia-reperfusion injury
dc.subject.keywordsselenium
dc.titleMyocardial Antioxidant Enzyme Systems, Ischemia-Reperfusion Injury, and Selenium
dc.typeGriffith thesis
gro.rights.copyrightThe author owns the copyright in this thesis, unless stated otherwise.
gro.hasfulltextFull Text
dc.contributor.otheradvisorHarrison, Glenn
dc.contributor.otheradvisorHeadrick, John
dc.rights.accessRightsPublic
gro.identifier.gurtIDgu1316666182145
gro.identifier.ADTnumberadt-QGU20060809.150846
gro.source.ADTshelfnoADT0
gro.source.GURTshelfnoGURT
gro.thesis.degreelevelThesis (PhD Doctorate)
gro.thesis.degreeprogramDoctor of Philosophy (PhD)
gro.departmentSchool of Health Sciences
gro.griffith.authorVenardos, Kylie


Files in this item

This item appears in the following Collection(s)

Show simple item record