Premium
Electrophoretic separation of amyloid β peptides in plasma
Author(s) -
Lewczuk Piotr,
Esselmann Hermann,
Bibl Mirko,
Paul Sabine,
Svitek Jana,
Miertschischk Johannes,
Meyrer Robert,
Smirnov Alexandr,
Maler Juan Manuel,
Klein Christian,
Otto Markus,
Bleich Stefan,
Sperling Wolfgang,
Kornhuber Johannes,
Rüther Eckhard,
Wiltfang Jens
Publication year - 2004
Publication title -
electrophoresis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.666
H-Index - 158
eISSN - 1522-2683
pISSN - 0173-0835
DOI - 10.1002/elps.200406068
Subject(s) - peptide , chemistry , gel electrophoresis , cerebrospinal fluid , polyacrylamide gel electrophoresis , amyloid beta , sodium dodecyl sulfate , electrophoresis , amyloid (mycology) , immunoprecipitation , urea , amyloid precursor protein , chromatography , alzheimer's disease , biochemistry , microbiology and biotechnology , biology , medicine , enzyme , disease , inorganic chemistry , gene
Abstract In this prospective study, for the first time we have separated and quantified amyloid β (Aβ) peptides in the plasma of patients with Alzheimer's disease (AD, n = 8) and age‐ and environment‐matched healthy controls ( n = 9) with urea‐based Aβ‐sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE)/immunoblot. In addition to the Aβ peptides 1–37/38/39/40/42, which we recently identified as regular constituents of human cerebrospinal fluid (CSF), we have observed a novel electrophoretic band migrating slightly cathodically to Aβ1–42. Since a standard peptide with the amino acid sequence Aβ2–40 migrates in the same position, we hypothesize that this plasma‐specific band may correspond to Aβ2–40. The concentration of Aβ peptides in the plasma has been approximately 100‐fold lower compared to the CSF. Interestingly, the concentration of the two shortest peptides and the longest one of these considered here ( i.e. , Aβ1–37/38/42) have increased significantly when the samples have been frozen at –80°C before immunoprecipitation, while the ‘middle‐length' peptides ( i.e. , Aβ1–39/40) have not been affected by this procedure. We have not observed significant differences of the Aβ peptides concentrations between AD and control subjects. Our method can be used to investigate the significance of plasma Aβ peptides in neurodegenerative disorders, and to monitor the efficiency of drugs with β/γ‐secretase inhibitory potency.