UUnniivveerrssiittyy ooff KKeennttuucckkyy UUKKnnoowwlleeddggee University of Kentucky Doctoral Dissertations Graduate School 2006 IINNCCRREEAASSEEDD OOXXIIDDAATTIIVVEE DDAAMMAAGGEE TTOO DDNNAA AANNDD TTHHEE EEFFFFEECCTTSS OONN MMIITTOOCCHHOONNDDRRIIAALL PPRROOTTEEIINN IINN AALLZZHHEEIIMMEERR''SS DDIISSEEAASSEE Jianquan Wang University of Kentucky, [email protected] RRiigghhtt cclliicckk ttoo ooppeenn aa ffeeeeddbbaacckk ffoorrmm iinn aa nneeww ttaabb ttoo lleett uuss kknnooww hhooww tthhiiss ddooccuummeenntt bbeenneefifittss yyoouu.. RReeccoommmmeennddeedd CCiittaattiioonn Wang, Jianquan, "INCREASED OXIDATIVE DAMAGE TO DNA AND THE EFFECTS ON MITOCHONDRIAL PROTEIN IN ALZHEIMER'S DISEASE" (2006). University of Kentucky Doctoral Dissertations. 300. https://uknowledge.uky.edu/gradschool_diss/300 This Dissertation is brought to you for free and open access by the Graduate School at UKnowledge. It has been accepted for inclusion in University of Kentucky Doctoral Dissertations by an authorized administrator of UKnowledge. For more information, please contact [email protected]. ABSTRACT OF DISSERTATION Jianquan Wang The Graduate School University of Kentucky 2006 INCREASED OXIDATIVE DAMAGE TO DNA AND THE EFFECTS ON MITOCHONDRIAL PROTEIN IN ALZHEIMER’S DISEASE ——————————————— ABSTRACT OF DISSERTATION ______________________________ A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the College of Arts and Sciences at the University of Kentucky By Jianquan Wang Lexington, Kentucky Director: Dr. Mark A. Lovell, Associate Professor of Chemistry Lexington, Kentucky 2006 Copyright © Jianquan Wang 2006 ABSTRACT OF DISSERTATION INCREASED OXIDATIVE DAMAGE TO DNA AND THE EFFECTS ON MITOCHONDRIAL PROTEIN IN ALZHEIMER’S DISEASE Alzheimer’s disease (AD) is a progressive, irreversible, neurodegenerative disease. The key to understanding AD is to elucidate the pathogenesis of neuron degeneration in specific brain regions. We hypothesize that there is increased DNA oxidation in AD brain compared to age-matched control subjects, especially in mitochondrial DNA (mtDNA), and that the changes in DNA bases will affect protein expression in mitochondria and contribute to neurodegeneration in AD. To test this hypothesis: 1) We quantified multiple oxidized bases in nuclear DNA (nDNA) and mtDNA of frontal, parietal, and temporal lobes and cerebellum from late-stage AD (LAD), mild cognitive impairment (MCI), and age-matched control subjects using gas chromatography/mass spectrometry with selective ion monitoring (GC/MS-SIM). Also, we quantified oxidized DNA bases in cortex of APP/PS1 transgenic mice. (a) nDNA and mtDNA were extracted from eight LAD and eight control subjects. We found levels of multiple oxidized bases were significantly higher in frontal, parietal, and temporal lobes and that mtDNA had approximately 10-fold higher levels of oxidized bases than nDNA. Eight-hydroxyguanine was approximately 10-fold higher than other oxidized base adducts in both LAD and control subjects. These results suggest that oxidative damage to mtDNA may contribute to the neurodegeneration of AD. (b) Mild Cognitive Impairment (MCI), the phase between normal aging and early dementia, is a common problem in the elderly with many subjects going on to develop AD. Results from eight amnestic MCI and six control subjects suggest oxidative damage to DNA occurs in the earliest detectable phase of AD. (c) Analysis of nDNA from the cortex of four groups (3m, 6m, 9m, 12m) of APP/PS1 and wild type mice showed elevations of 8-hydroxyguanine in 12 month old APP/PS1 mice. 2) To analyze mitochondrial protein changes in LAD, 2D gels were run to separate proteins and MALDI-TOF mass spectrometry was used to identify proteins. Five mitochondrial proteins were significantly decreased in LAD. This proteomic study provides a proteome map of mitochondria in LAD brain and an insight into the pathogenesis of neuron degeneration in Alzheimer’s disease. Key words: Alzheimer’s disease, Mild Cognitive Impairment, Nuclear and mitochondrial DNA oxidation, Proteomics, Mass Spectrometry Jianquan Wang October 5, 2006 INCREASED OXIDATIVE DAMAGE TO DNA AND THE EFFECTS ON MITOCHONDRIAL PROTEIN IN ALZHEIMER’S DISEASE By Jianquan Wang Dr. Mark A. Lovell Director of Dissertation Dr. Robert B. Grossman Director of Graduate Study October 5, 2006 RULES FOR THE USE OF DISSERTATION Unpublished dissertation submitted for the Doctor’s degree and deposited in the University of Kentucky Library are as a rule open for inspection, but are to be used only with due regard to the rights of the authors. Bibliographical references may be noted, but quotations or summaries of parts may be published with only permission of the author, and with the usual scholarly acknowledgements. Extensive copying or publication of the dissertation in whole or in part also requires the consent of the Dean of the Graduate School of the University of Kentucky. A library that borrows this dissertation for use by its patrons is expected to secure the signature of each user. Name Date _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ DISSERTATION Jianquan Wang The Graduate School University of Kentucky 2006 INCREASED OXIDATIVE DAMAGE TO DNA AND THE EFFECTS ON MITOCHONDRIAL PROTEIN IN ALZHEIMER’S DISEASE ———————————————— DISSERTATION ________________________________ A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the College of Arts and Sciences at the University of Kentucky By Jianquan Wang Lexington, Kentucky Director: Dr. Mark A. Lovell, Associate Professor of Chemistry Lexington, Kentucky 2006 Copyright © Jianquan Wang 2006 ACKNOWLEDGEMENTS I would like to acknowledge many people sincerely for helping and supporting me during my doctoral research. Thanks and appreciation especially go to my advisor, Dr. Mark A Lovell, who has helped me on every step: financial support, scientific thinking, speaking, and writing. The inspiration for doing my research is that Dr. Lovell provided me an outstanding research environment and excellent program. I could not count how many times he revised my paper and dissertation drafts to better my work. I am very grateful for having this exceptional committee, Dr. Steve Estus, Dr. Bert Lynn, and Dr. Edward DeMoll, and wish to thank them for their support and contribution. I appreciate the opportunity to operate mass spectrometries Dr. Lynn has provided. I would like to extend many thanks to Dr. William Markesbery, Director of Sander-Brown Center on Aging, who provided excellent human tissue for my research. Also many thanks go to Dr. Daret K St Clair, who provided transgenic mice for my animal studies. My thanks also must go to my colleagues and friends: Shuling Xiong, Chengsong Xie, Jennifer Smith, Changxing Shao, etc, who have helped me over the years. Finally, I would like to thank my family for their encouragement, enthusiasm, and constant support. iii
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