Two immunochemical assays to measure advanced glycation end-products in serum from dialysis patients.
Clin Chem Lab Med
; 43(5): 503-11, 2005.
Article
em En
| MEDLINE
| ID: mdl-15899672
ABSTRACT
Advanced glycation end-products are uremic toxins that accumulate in the serum and tissues of patients with chronic renal failure. Here, we established two enzyme-linked immunosorbent assays (ELISAs) for N(epsilon)-carboxymethyllysine and imidazolone to analyze advanced glycation end-products in human serum. Both ELISAs detected advanced glycation end-products bound to human serum albumin in a dose-dependent way. Whereas the formation of imida-zolone was independent of the presence of oxygen, concentrations of N(epsilon)-carboxymethyllysine epitopes increased 20-fold under oxidative conditions. The N(epsilon)-carboxymethyllysine ELISA showed a similar response to free, peptide-bound and protein-bound N(epsilon)-carboxymethyllysine, whereas the imidazolone antibody showed slightly higher affinity toward peptide-bound compared to protein-bound imidazolone. In human serum, linear dilution ranges from 110 to 140 (N(epsilon)-carboxymethyllysine ELISA) and from 12 to 18 (imidazolone ELISA) were found. The recovery of N(epsilon)-carboxymethyllysine from serum was 101 +/- 10% and 94 +/- 12%, respectively, and 93 +/- 15% and 97 +/- 12% for imidazolone. The coefficients of variation for intra-assay variability were 0.26-2.7% (N(epsilon)-carboxymethyllysine) and 0.1-2.4% (imidazolone), and 8.3-13.4% (N(epsilon)-carboxymethyllysine) and 7.8-12.5% (imidazolone) for inter-assay variability. In serum samples from hemodialysis patients (n = 20) and controls (n =20), an approximately two-fold increase was detected in the patient group (p < 0.001). The combination of the N(epsilon)-carboxymethyllysine and imidazolone ELISAs is a valuable tool to measure serum concentrations of advanced glycation end-products for clinical studies.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ensaio de Imunoadsorção Enzimática
/
Diálise Renal
/
Produtos Finais de Glicação Avançada
/
Lisina
Tipo de estudo:
Observational_studies
Limite:
Adult
/
Aged
/
Humans
/
Middle aged
Idioma:
En
Ano de publicação:
2005
Tipo de documento:
Article