Oxidized proteins in Alzheimer's plasma.
The levels of oxidatively modified proteins were examined in blood from Alzheimer's disease (AD) patients, non-AD controls, and AD relatives. Oxidative modification was measured by reacting the protein carbonyls with 2,4-dinitrophenyl hydrazine (DNPH). The total oxidized proteins were determined by HPLC, while specific protein oxidation was assessed from Western blots of electrophoretic gels using antibody to the DNP derivatives. Statistically significant elevations (P < 0.05) of total oxidized proteins were observed in both AD subjects and AD relatives when compared with non-AD controls. Moreover, a protein band (e.g., MW = 78-kDa) was uniquely oxidized in the plasma of AD subjects. Furthermore, this protein from AD subjects was more susceptible to in vitro oxidation. These data suggest that such oxidized proteins may be useful as biomarkers for the detection and evaluation of AD.
Conrad
C C
CC
Molecular Aging Unit, University of North Texas Health Science Center, Fort Worth, Texas 76107, USA.
Marshall
P L
PL
Talent
J M
JM
Malakowsky
C A
CA
Choi
J
J
Gracy
R W
RW
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood*; D001798:Blood Proteins / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008875:Middle Aged; D010084:Oxidation-Reduction; D010659:Phenylhydrazines / Q000737:chemistry
D001798:Blood Proteins; D010659:Phenylhydrazines; C004787:2,4-dinitrophenylhydrazine