title: Determination of the oxido-redox status of plasma albumin in hemodialysis patients.
abstract: The oxido-redox status of plasma albumin in patients treated with hemodialysis was characterized with LC-ESI-MS/MS and was compared with models of oxidative stress. Oxidised albumin was characterized by sulfonation (SO3-) of the SH at Cys 34, unfolding and acidification of the molecule. Albumin in hemodialysis patients presented, instead, only intermediate oxidation products such as sulfenic (SO2), sulfonic (SO)and methionine sulfoxide (C5H9NO2S) involving Cys 165-269 and Met 329-548 but did not present SO3- at Cys 34. Absence of charge and structural alterations compared to the oxidised templates was also confirmed with electrophoretic titration and calorimetry. In conclusion, the oxido-redox status of plasma albumin in hemodialysis patients lacks the hallmarks of the advanced oxidation products. LC-ESI-MS/MS was crucial to characterize albumin in conditions of oxidation stress; surrogate techniques can mirror conformational changes induced by oxidation.
authors.affiliation: Laboratory on Pathophysiology of Uremia, G. Gaslini Children Hospital, Genoa, Italy; Renal Child Foundation, Genoa, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Bruschi
authors.forename: Andrea
authors.initials: A
authors.lastname: Petretto
authors.forename: Giovanni
authors.initials: G
authors.lastname: Candiano
authors.forename: Luca
authors.initials: L
authors.lastname: Musante
authors.forename: Ezio
authors.initials: E
authors.lastname: Movilli
authors.forename: Laura
authors.initials: L
authors.lastname: Santucci
authors.forename: Andrea
authors.initials: A
authors.lastname: Urbani
authors.forename: Rosanna
authors.initials: R
authors.lastname: Gusmano
authors.forename: Enrico
authors.initials: E
authors.lastname: Verrina
authors.forename: Giovanni
authors.initials: G
authors.lastname: Cancarini
authors.forename: Francesco
authors.initials: F
authors.lastname: Scolari
authors.forename: Gian Marco
authors.initials: GM
authors.lastname: Ghiggeri
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002152:Calorimetry, Differential Scanning; D002853:Chromatography, Liquid; D005260:Female; D006801:Humans; D008297:Male; D008715:Methionine / Q000031:analogs & derivatives / Q000097:blood; D008875:Middle Aged; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D006435:Renal Dialysis; D012709:Serum Albumin / Q000032:analysis / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013434:Sulfenic Acids / Q000097:blood; D013451:Sulfonic Acids / Q000097:blood; D053719:Tandem Mass Spectrometry
chemical_list: D012709:Serum Albumin; D013434:Sulfenic Acids; D013451:Sulfonic Acids; D008715:Methionine; C013111:methionine sulfoxide