Open AccessAlterations in conformational state of albumin in plasma in chronic hemodialyzed patients
Author(s) -
Anna Pieniążek,
Łukasz Gwoździński,
Zbigniew Zbróg,
Krzysztof Gwoździński
Publication year - 2018
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0192268
Subject(s) - albumin , chemistry , serum albumin , maleimide , oxidizing agent , oxidative stress , thiol , reactive oxygen species , biochemistry , organic chemistry
Objective In chronic hemodialyzed (CH) patients the balance between production of reactive oxygen species and antioxidant defense system is disturbed and shifted towards oxidative conditions. The properties of albumin in CH patients were studied before hemodialysis (HD) and post-HD. Methods Two oxidants were applied, organic t-butyl hydroperoxide (t-BOOH) and inorganic hydroperoxide (H 2 O 2 ), for oxidation of albumin molecules. By comparison, albumin from healthy donors was also modified by both oxidants. The thiol content in albumin was determined by the Ellman method. Albumin properties were evaluated with the spin labelling technique using two covalently bound spin labels, maleimide (MSL) and iodoacetamide (ISL), and fatty acid spin probe, 16-doxylstearic acid (16-DS). Results A decrease in thiols level in HD albumin was greater than in control albumin. The t-BOOH modified the microenvironment at the binding site of MSL and ISL in control albumin molecules to a greater extent than hydrogen peroxide. Control albumin treated with t-BOOH and H 2 O 2 showed an increase in the mobility of 16-DS. However, no changes were observed in albumin from CH patients treated with either of the oxidizing agents. Conclusion Both oxidants induced strong conformational changes in albumin from healthy volunteers, but were less effective or ineffective in modification of albumin derived from CH patients. These results show that albumin from CH patients is highly modified in vivo and is not vulnerable to oxidation in the same way as normal albumin.