Differential Expression and Redox Proteomics Analyses of an Alzheimer Disease Transgenic Mouse Model: Effects of the Amyloid-β Peptide of APPΞ

Among the pathological factors known to be associated with Alzheimer disease (AD), oxidative stress induced by the amyloid-β peptide (Aβ) has been demonstrated to play a key role in human brain and animal models of AD. Recently, we reported elevated levels of oxidative damage in the brain of a transgenic (Tg) AD mouse model with Swedish and Indiana familial AD mutations in human amyloid precursor protein (APP) [PDAPP mice, line J20], as evidenced by increased levels of protein carbonyls, 3-nitrotyrosine, and protein-bound 4-hydroxy-2-nonenal. This oxidative damage was dependent on the methionine 35 residue within the Aβ peptide. Further insight into the molecular pathways affected in this Tg model of AD may be gained with discovery-based proteomics studies; therefore, two-dimensional gel-based expression proteomics was performed to compare differences in brain protein levels of J20 Tg mice with non-transgenic (NTg) littermate controls. Based on our studies, we identified six proteins that had significantly increased levels in J20 Tg relative to NTg mice: calcineurin subunit B type 1, ρ GDP-dissociation inhibitor 1, Tcomplex protein 1 subunit α A, α-enolase, peptidyl-prolyl cis-trans isomerase (Pin-1), and ATP synthase subunit α mitochondrial. Several of these proteins have previously been implicated in in vitro and in vivo models and subjects with AD. Additionally, using redox proteomics analyses we identified two oxidatively-modified proteins: phosphatidylethanolamine-binding protein 1 and Pin-1 with decreased levels of protein 3-nitrotyrosine in J20 Tg mice relative to NTg. Western blotting and immunoprecipitation analyses were used to validate proteomics results. Overall, these ΞThis manuscript is dedicated to the life and career of William R. Markesbery, MD, a pioneer and extraordinary presence in the field of AD research, and a deep personal friend. Dr. Markesbery died January 30, 2010, leaving an exemplary record of achievement and a life well-lived. * Address correspondence to: Professor D. Allan Butterfield, Department of Chemistry, Center of Membrane Sciences, and SandersBrown Center on Aging, University of Kentucky, Lexington, KY 40506, Ph: (859) 257-3184, Fax: (859) 257-5876, dabcns@uky.edu. 3Current address: Department of Physiology and The Barshop Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX §Current address: University of Pittsburgh, Department of Chemistry, Pittsburgh, PA 15260 Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Author Manuscript Neuroscience. Author manuscript; available in PMC 2012 March 17. Published in final edited form as: Neuroscience. 2011 March 17; 177: 207–222. doi:10.1016/j.neuroscience. 2011.01. 005. N IH PA Athor M anscript N IH PA Athor M anscript N IH PA Athor M anscript studies provide information about changes in the brain proteome as a result of Aβ deposition and clues with which to further direct studies on elucidating AD pathogenesis.