Formation of albumin dimers induced by exposure to peroxides in human plasma: a possible biomarker for oxidative stress.
Human serum albumin (HSA) has one free thiol residue at Cys-34 that is likely oxidized by various reactive oxygen species (ROS). We attempted to identify the oxidation product of Cys-34 of HSA following exposure of plasma to ROS. Oxidation induced by tert-butyl hydroperoxide (t-BuOOH) of this free cysteine residue in HSA was observed in detail. Analysis of oxidized albumin in a partially purified fraction obtained by affinity column chromatography clearly revealed the formation of albumin disulfide dimers following t-BuOOH exposure. Albumin disulfide dimer formation was observed in normal plasma following treatment with various peroxides, as well as in untreated plasma from patients on hemodialysis using SDS-PAGE and Western blot analysis. The present results indicate that albumin dimers are oxidative products derived from peroxides, and that their presence in plasma might be a marker of oxidative stress as secondary metabolites of peroxidation.
Ogasawara
Yuki
Y
Department of Environmental Biology, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan. yo@my-pharm.ac.jp
Namai
Tomoyuki
T
Togawa
Tadayasu
T
Ishii
Kazuyuki
K
D000328:Adult; D015415:Biomarkers; D002847:Chromatography, Agarose; D003545:Cysteine / Q000378:metabolism; D019281:Dimerization; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology*; D010545:Peroxides / Q000097:blood / Q000378:metabolism*; D012685:Sepharose / Q000031:analogs & derivatives; D012709:Serum Albumin / Q000302:isolation & purification / Q000378:metabolism*; D020122:tert-Butylhydroperoxide
D015415:Biomarkers; D010545:Peroxides; D012709:Serum Albumin; C029483:Blue-Sepharose; D012685:Sepharose; D020122:tert-Butylhydroperoxide; D003545:Cysteine