title: Oxidative damage of albumin in advanced liver disease.
abstract: Albumin has a number of biological functions and the serum albumin level is related to prognosis in advanced liver disease. Oxidative stress is believed to play an important role in the pathogenesis of liver failure. The aim of the present study was to characterize oxidative modification of albumin in patients with various degrees of liver failure and to investigate implications for its binding function. Patients with liver cirrhosis (n=10), acute-on-chronic liver failure (n=8) and healthy controls (n=15) were included in the study. Three fractions of albumin were separated by HPLC according to the redox state of cysteine-34 and detected by fluorescence as well as UV absorption. Carbonyl groups were measured as a marker of oxidative modification in plasma proteins and, by western blotting, on albumin. Progressive oxidative modification of albumin was found with increasing severity of liver failure indicated by an increased content of carbonyl groups and oxidation of cysteine-34. Fluorescence properties of albumin were altered by oxidation and, in patients with acute-on-chronic liver failure, by high plasma levels of bilirubin. This alteration of albumin fluorescence by bilirubin provides evidence for a preferred binding of bilirubin to the fully reduced form of albumin.
authors.affiliation: Institute of Physiological Chemistry, Center of Physiological Medicine, Medical University of Graz, Austria. karl.oettl@meduni-graz.at <karl.oettl@meduni-graz.at>
authors.forename: Karl
authors.initials: K
authors.lastname: Oettl
authors.forename: Vanessa
authors.initials: V
authors.lastname: Stadlbauer
authors.forename: Franz
authors.initials: F
authors.lastname: Petter
authors.forename: Joachim
authors.initials: J
authors.lastname: Greilberger
authors.forename: Csilla
authors.initials: C
authors.lastname: Putz-Bankuti
authors.forename: Seth
authors.initials: S
authors.lastname: Hallström
authors.forename: Carolin
authors.initials: C
authors.lastname: Lackner
authors.forename: Rudolf E
authors.initials: RE
authors.lastname: Stauber
mesh_terms: D001663:Bilirubin / Q000097:blood; D015153:Blotting, Western; D016022:Case-Control Studies; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D008103:Liver Cirrhosis / Q000097:blood; D017093:Liver Failure / Q000097:blood*; D017114:Liver Failure, Acute / Q000097:blood; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D012709:Serum Albumin / Q000737:chemistry / Q000378:metabolism*
chemical_list: D012709:Serum Albumin; D001663:Bilirubin