Alteration of redox state of human serum albumin before and after hemodialysis.
BACKGROUND
Persistent hypoalbuminemia is a predictor of death in long-term maintenance hemodialysis patients, although cardiovascular diseases remain the leading cause of death. A decreased serum antioxidant activity in maintenance hemodialysis patients may contribute to increased oxidative damage, and may be associated with accelerated atherosclerotic changes.


METHODS
The aim of this study was to examine the redox state of human serum albumin in maintenance hemodialysis patients by high-performance liquid chromatography (HPLC) using a fluorescence detector.


RESULTS
HPLC of human serum albumin on a Shodex-Asahipak ES-502N column at pH 4.85 showed a clear resolution of human mercaptalbumin (HMA) and nonmercaptalbumin (HNA), which are the reduced and oxidized forms of human serum albumin, respectively. The mean +/- SD percentage of the HMA fraction of human serum albumin was significantly lower in maintenance hemodialysis patients than in age-matched normal subjects. The percentage of HMA increased 3-5 h after starting the hemodialysis and then decreased to subnormal levels.


CONCLUSIONS
This suggests that serum albumin may be a major extracellular antioxidant in maintenance hemodialysis patients, and that hemodialysis may rescue serum albumin reduction by inducing intermolecular sulfhydryl-disulfide exchange reaction.
Soejima
Akinori
A
First Department of Internal Medicine, Kyorin University School of Medicine, Tokyo, Japan. soejim@aol.com
Matsuzawa
Naoki
N
Hayashi
Tomoya
T
Kimura
Rio
R
Ootsuka
Takako
T
Fukuoka
Kazuhito
K
Yamada
Akira
A
Nagasawa
Toshihiko
T
Era
Seiichi
S
D000328:Adult; D000368:Aged; D002851:Chromatography, High Pressure Liquid; D004220:Disulfides / Q000097:blood; D005260:Female; D006801:Humans; D034141:Hypoalbuminemia / Q000097:blood*; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction; D006435:Renal Dialysis / Q000009:adverse effects; D012709:Serum Albumin / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000097:blood
D004220:Disulfides; D012709:Serum Albumin; D013438:Sulfhydryl Compounds; C001702:mercaptoalbumin