title: The evaluation of the oxidative state of native-LDL: three methods compared.
abstract: LDL-oxidation is considered a contributing factor to the development of atherosclerotic lesions. However, to utilise the oxidative state of LDL as a marker of cardiovascular risk, reliable analytical methods for its detection must be defined. We have compared three methods for their capacity to evaluate the difference in the oxidation state of isolated LDL subjected to either dialysis (D-LDL) or gel filtration (F-LDL) to remove EDTA. Their susceptibility to oxidation promoted by Cu(2+) was monitored by following the time course of conjugated diene (CD) and lipid hydroperoxide (ROOH) accumulation. The relative electrophoretic mobility (REM) of the same LDL samples was evaluated by capillary electrophoresis. As measured by all three methods, F-LDL are less prone to oxidation than D-LDL when added with CuSO(4). REM of F-LDL and D-LDL significantly differs already before the addition of the metal catalyst, whereas CD and ROOH contents become significantly different only after it. Besides confirming that a rapid centrifugation followed by gel filtration is a more convenient procedure than dialysis to remove EDTA during LDL isolation, our study suggests the REM of isolated-LDL as the biochemical marker of choice in the evaluation of its oxidative state.
authors.affiliation: University of Sassari, Viale S. Pietro 43/b, Sassari, I-07100, Italy. carru@uniss.it <carru@uniss.it>
authors.forename: Ciriaco
authors.initials: C
authors.lastname: Carru
authors.forename: Angelo
authors.initials: A
authors.lastname: Zinellu
authors.forename: Franca
authors.initials: F
authors.lastname: Galistu
authors.forename: Monserrata
authors.initials: M
authors.lastname: Barca
authors.forename: Valeria
authors.initials: V
authors.lastname: Pasciu
authors.forename: Fiorenza
authors.initials: F
authors.lastname: Lumbau
authors.forename: Bastiano
authors.initials: B
authors.lastname: Sanna
authors.forename: Bruna
authors.initials: B
authors.lastname: Tadolini
authors.forename: Luca
authors.initials: L
authors.lastname: Deiana
mesh_terms: D008078:Cholesterol, LDL / Q000032:analysis* / Q000737:chemistry*; D019327:Copper Sulfate / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D015227:Lipid Peroxidation; D010084:Oxidation-Reduction; D013057:Spectrum Analysis / Q000379:methods*; D014462:Ultrafiltration / Q000379:methods*
chemical_list: D008078:Cholesterol, LDL; D019327:Copper Sulfate