Proteins in human brain cortex are modified by oxidation, glycoxidation, and lipoxidation. Effects of Alzheimer disease and identification of lipoxidation targets.
Diverse oxidative pathways, such as direct oxidation of amino acids, glycoxidation, and lipoxidation could contribute to Alzheimer disease pathogenesis. A global survey for the amount of structurally characterized probes for these reactions is lacking and could overcome the lack of specificity derived from measurement of 2,4-dinitrophenylhydrazine reactive carbonyls. Consequently we analyzed (i) the presence and concentrations of glutamic and aminoadipic semialdehydes, N(epsilon)-(carboxymethyl)-lysine, N(epsilon)-(carboxyethyl)-lysine, and N(epsilon)-(malondialdehyde)-lysine by means of gas chromatography/mass spectrometry, (ii) the biological response through expression of the receptor for advanced glycation end products, (iii) the fatty acid composition in brain samples from Alzheimer disease patients and age-matched controls, and (iv) the targets of N(epsilon)-(malondialdehyde)-lysine formation in brain cortex by proteomic techniques. Alzheimer disease was associated with significant, although heterogeneous, increases in the concentrations of all evaluated markers. Alzheimer disease samples presented increases in expression of the receptor for advanced glycation end products with high molecular heterogeneity. Samples from Alzheimer disease patients also showed content of docosahexaenoic acid, which increased lipid peroxidizability. In accordance, N(epsilon)-(malondialdehyde)-lysine formation targeted important proteins for both glial and neuronal homeostasis such as neurofilament L, alpha-tubulin, glial fibrillary acidic protein, ubiquinol-cytochrome c reductase complex protein I, and the beta chain of ATP synthase. These data support an important role for lipid peroxidation-derived protein modifications in Alzheimer disease pathogenesis.
Pamplona
Reinald
R
Metabolic Pathophysiology Research Group, Departament de Ciències Mèdiques Bàsiques, Facultat de Medicina i Ciències de la Salut, Universitat de Lleida, c/Montserrat Roig,2. E-25008 Lleida, Spain.
Dalfó
Esther
E
Ayala
Victòria
V
Bellmunt
Maria Josep
MJ
Prat
Joan
J
Ferrer
Isidre
I
Portero-Otín
Manuel
M
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism*; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism*; D002244:Carbon / Q000737:chemistry; D002540:Cerebral Cortex / Q000378:metabolism*; D019992:Databases as Topic; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D005227:Fatty Acids / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000737:chemistry; D017127:Glycation End Products, Advanced / Q000378:metabolism; D006019:Glycolysis; D006801:Humans; D050356:Lipid Metabolism; D015227:Lipid Peroxidation; D008239:Lysine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D008297:Male; D008315:Malondialdehyde / Q000737:chemistry; D009245:NADH Dehydrogenase / Q000378:metabolism; D010100:Oxygen / Q000737:chemistry* / Q000378:metabolism; D010659:Phenylhydrazines / Q000737:chemistry; D011506:Proteins / Q000737:chemistry; D016622:Silver Staining; D014451:Ubiquinone / Q000031:analogs & derivatives* / Q000737:chemistry
D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D005904:Glial Fibrillary Acidic Protein; D017127:Glycation End Products, Advanced; C464486:N(epsilon)-(malondialdehyde)lysine; D010659:Phenylhydrazines; D011506:Proteins; D014451:Ubiquinone; C004787:2,4-dinitrophenylhydrazine; D008315:Malondialdehyde; C048496:N(6)-carboxymethyllysine; D002244:Carbon; D009245:NADH Dehydrogenase; D008239:Lysine; C003741:ubiquinol; D010100:Oxygen