Renal clearance of glycation adducts: anti-glycation defence in uraemia and dialysis.

Increased plasma concentrations of free AGEs (advanced glycation end products) in uraemia are due to impaired renal clearance exacerbated by dietary load and breakdown of the elevated protein-bound AGEs. Increased protein-bound AGEs most probably reflect increased synthesis due to the increased oxidative and carbonyl stress of uraemia, which is exacerbated by the dialysis procedure. Use of biocompatible peritoneal dialysis fluids and haemodialysis membranes will be beneficial, but strategies to further reduce AGE formation are required. These should focus on the hydroimidazalone AGEs, which are quantitatively the most important, and not only on the conventionally monitored AGEs N (epsilon)-carboxymethyl-lysine and pentosidine.