In:
Peritoneal Dialysis International: Journal of the International Society for Peritoneal Dialysis, SAGE Publications, Vol. 23, No. 1 ( 2003-01), p. 23-32
Abstract:
Glucose degradation products (GDP) in dialysis fluids may induce nonenzymatic protein modifications, the chemical nature and biological properties of which should be better defined. ← Aims To characterize nonenzymatic protein modifications present in glucose-based peritoneal dialysis fluids (PDF) and to evaluate the relationship between concentrations of GDP and the derived nonenzymatic modifications, and the potential of PDF for generating these modifications in vitro. ← Methods The presence, distribution, and content of several nonenzymatic protein modifications in PDF were evaluated by immunological methods, by HPLC, and by gas chromatography-mass spectrometry (GC/MS). Peritoneal dialysis fluid-induced oxidative stress in cells was evaluated by flow cytometry. The potential of PDF for generating oxidative and glycoxidative modifications was examined by immunological and cross-linking analyses. ← Results The albumin present in PDF is modified by carboxymethyllysine (CML). GC/MS analyses of PDF proteins confirmed the presence of CML and demonstrated the occurrence of carboxyethyllysine, malondialdehyde lysine, and oxidation-derived semialdehydes. Furthermore, their concentrations in PDF proteins were significantly higher than those in plasma proteins (in all cases, p 〈 0.02). The concentration of pyrraline, a non-oxidative advanced glycation end-product, increased with dwell time up to 6 hours ( p 〈 0.03). The PDF induced cellular free-radical production, which was partially inhibited by the Maillard reaction inhibitor aminoguanidine ( p 〈 0.001). The potential to generate oxidative and glycoxidative modifications demonstrated an inverse relationship with dwell time ( p 〈 0.05). The PDF was able to induce collagen cross-linking in a close relationship with GDP concentration. ← Conclusions ( 1 ) PDF contains non-oxidative and several oxidative nonenzymatic protein modifications in higher concentrations than plasma. ( 2 ) Peritoneal dialysis fluid induces oxidative stress in vitro, which can be partially inhibited by aminoguanidine. ( 3 ) These properties are directly related to GDP concentration. ( 4 ) Peritoneal dialysis fluid is able to generate glycoxidative and oxidative damage to proteins in vitro in a dwell-time dependent fashion.
Type of Medium:
Online Resource
ISSN:
0896-8608
,
1718-4304
DOI:
10.1177/089686080302300103
Language:
English
Publisher:
SAGE Publications
Publication Date:
2003
detail.hit.zdb_id:
2075957-5
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