title: Capillary electrophoresis for the analysis of the effect of sample preparation on early stages of Aβ1-40 aggregation.
abstract: Aggregation of the amyloid-β protein (Aβ) contributes to the neurodegeneration characteristic of Alzheimer's disease. Of particular importance are the early stages of aggregation, which involve the formation of soluble oligomers and protofibrils. In these studies, we demonstrate the potential for CE with UV detection using a polyethylene oxide separation matrix to identify the evolution of various oligomeric species of Aβ1-40 . To demonstrate the efficacy of this technique, UV-CE was utilized to compare two methods commonly used to prepare Aβ for aggregation experiments and their effect on the formation of early aggregates. SEC-purified Aβ1-40 initially contained more small species, including monomer, than did freshly dissolved Aβ1-40 pretreated with hexafluoroisopropanol. Strikingly, the lag time to oligomer formation for SEC-isolated Aβ1-40 samples was ∼23 h shorter compared to freshly dissolved Aβ1-40 samples. Furthermore, oligomers formed from the aggregation of SEC-purified Aβ1-40 persisted within solution for a longer period of time. These results indicate that the initial sample preparation has a drastic influence on the early stages of Aβ1-40 aggregation. This is the first report of the use of UV-CE with a separation matrix to study the effect of sample preparation on early aggregation of Aβ1-40 . UV-CE was also used in parallel with dot blot analysis and inhibitory compounds to discern structural characteristics of individual oligomer peaks, demonstrating the capacity of UV-CE as a complimentary technique to further understand the aggregation process.
authors.affiliation: Ralph E. Martin Department of Chemical Engineering, University of Arkansas, Fayetteville, AR, USA.
authors.forename: N Elizabeth
authors.initials: NE
authors.lastname: Pryor
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Moss
authors.forename: Christa N
authors.initials: CN
authors.lastname: Hestekin
mesh_terms: D016229:Amyloid beta-Peptides / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D006801:Humans; D015151:Immunoblotting; D010446:Peptide Fragments / Q000737:chemistry*; D066329:Protein Aggregates; D011994:Recombinant Proteins / Q000737:chemistry
chemical_list: D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; D066329:Protein Aggregates; D011994:Recombinant Proteins; C078592:amyloid beta-protein (1-40)
keywords: Amyloid beta; Capillary electrophoresis; Dot blot; Oligomer
references.citation: Anal Chem. 2007 Jul 1;79(13):4887-91
references.pmid: 17536782
references.citation: J Mol Biol. 1992 Jun 20;225(4):1075-93
references.pmid: 1613791
references.citation: Anal Bioanal Chem. 2009 Dec;395(8):2509-19
references.pmid: 19838688
references.citation: J Biol Chem. 2007 Apr 6;282(14):10311-24
references.pmid: 17284452
references.citation: J Chromatogr B Analyt Technol Biomed Life Sci. 2011 Mar 15;879(9-10):627-32
references.pmid: 21334989
references.citation: J Neurosci. 1999 Oct 15;19(20):8876-84
references.pmid: 10516307
references.citation: J Neurochem. 2008 Oct;107(2):466-77
references.pmid: 18702666
references.citation: Biochemistry. 2002 May 14;41(19):6115-27
references.pmid: 11994007
references.citation: Anal Biochem. 2008 Jul 1;378(1):15-24
references.pmid: 18396143
references.citation: J Phys Chem B. 2010 Nov 25;114(46):15288-95
references.pmid: 20964446
references.citation: J Biol Chem. 2011 Aug 5;286(31):27081-91
references.pmid: 21652708
references.citation: J Neurosci. 2012 Jun 27;32(26):8767-77
references.pmid: 22745479
references.citation: J Chem Phys. 2008 Jan 28;128(4):045102
references.pmid: 18248009
references.citation: J Physiol. 2006 Apr 15;572(Pt 2):477-92
references.pmid: 16469784
references.citation: Proc Natl Acad Sci U S A. 2002 Dec 24;99(26):16742-7
references.pmid: 12481027
references.citation: Proc Natl Acad Sci U S A. 1998 May 26;95(11):6448-53
references.pmid: 9600986
references.citation: Electrophoresis. 2009 Apr;30(8):1418-29
references.pmid: 19306269
references.citation: J Neurochem. 2008 Jan;104(2):500-13
references.pmid: 17953673
references.citation: Nat Chem. 2009 Jul;1(4):326-31
references.pmid: 20703363
references.citation: Analyst. 2010 Jul;135(7):1631-5
references.pmid: 20448881
references.citation: J Am Chem Soc. 2005 Feb 23;127(7):2075-84
references.pmid: 15713083
references.citation: J Mol Biol. 2001 Oct 5;312(5):1103-19
references.pmid: 11580253
references.citation: Int J Mol Sci. 2012;13(3):3038-72
references.pmid: 22489141
references.citation: Biochemistry. 1997 Dec 2;36(48):14845-52
references.pmid: 9398206
references.citation: Nature. 2002 Apr 4;416(6880):535-9
references.pmid: 11932745
references.citation: Mol Neurodegener. 2007 Sep 26;2:18
references.pmid: 17897471
references.citation: Electrophoresis. 2004 Oct;25(18-19):3186-94
references.pmid: 15472964
references.citation: Biochemistry. 2009 Dec 15;48(49):11796-806
references.pmid: 19916493
references.citation: Phys Chem Chem Phys. 2010 Apr 14;12(14):3622-9
references.pmid: 20336261
references.citation: Phys Chem Chem Phys. 2011 Sep 7;13(33):15200-10
references.pmid: 21769359
references.citation: Nature. 2006 Mar 16;440(7082):352-7
references.pmid: 16541076
references.citation: Anal Biochem. 2012 Jun 15;425(2):104-12
references.pmid: 22446499
references.citation: J Neurosci. 2007 Mar 14;27(11):2866-75
references.pmid: 17360908
references.citation: Biochemistry. 1998 Mar 17;37(11):3602-11
references.pmid: 9521679
references.citation: J Neurosci. 2009 Aug 26;29(34):10582-7
references.pmid: 19710311
references.citation: ACS Chem Neurosci. 2011 Nov 16;2(11):645-57
references.pmid: 22860159
references.citation: Amyloid. 2000 Sep;7(3):166-78
references.pmid: 11019857
references.citation: J Biol Chem. 2012 Jul 13;287(29):24765-73
references.pmid: 22547072
references.citation: Eur Biophys J. 2009 Apr;38(4):355-67
references.pmid: 19005650