Analysis of Non Enzymatic Glycosylation In Vivo: Impact of Different Dialysis Solutions

Abstract

Background

Glucose-containing dialysis solutions in peritoneal dialysis (PC) patients induce non enzymatic glycosylation (NEG) within the peritoneal cavity. The subsequent formation of advanced glycosylation endproducts (AGEs) may be implicated in the functional deterioration of the peritoneal membrane in long-term PC patients.

Aim of the Study and Parameters

Measurement of NEG by the determination of percent glycation of albumin and IgG (GP), and of AGEs by measuring pentosidine content of protein in 4-hour effluents (Peff) and serum.

Subjects

In 5 patients each, a comparison was made between 3.86% glucose and 1.36% glucose (GP and Peff), and between 3.86% glucose and 7.5% icodextrin (Peff). Nine patients with clinically severe ultrafiltration failure (UFF) were compared to nine patients treated with PC for 1 month. Six of the patients with UFF were treated with non glucose dialysis solutions and Peff was studied again after 6 weeks.

Results

No difference was found between Peff comparing 3.86% glucose to either 1.36% glucose or icodextrin. GP were higher in 3.86% glucose than in 1.36%. Glycatedlnon glycated (G/NG) protein clearance ratios were 1.29 for albumin and 1.12 for IgG (p = 0.003). In contrast to GP, both Peff and serum pentosidine were higher in the UFF patients than in the recently started patients. Peff, but not GP, correlated with duration of PC (r = 0.67, p = 0.04). In 5 of 6 patients treated with non glucose dialysate, Peff decreased while serum pentosidine was stable. .Discussion: These data show that 4-hour Peff contents are not influenced by glucose concentration or osmolality, in contrast to GP. The relation between Peff and duration of PC, and the effect of non glucose dialysate on Peff, suggest that long-term glucose exposure is an important determinant of membrane glycosylation. Thus Peff probably reflects the long-term effects of intraperitoneal glycosylation of peritoneal membrane proteins. Treatment with non glucose dialysis solutions may result in “washout” of glycosylated proteins from the peritoneal membrane.