Role of the Maillard Reaction in Nephropathy

AGE formation is related to hyperglycaemia in diabetes, but not in uraemia, because AGE levels do not differ between diabetic and nondiabetic haemodialysis patients, which is a mystery.435 Pentosidine and CML were elevated in uraemic plasma and then-levels were not correlated with fructoselysine levels. The addition of aminoguanidine and OPB-9195 lowered the yield of AGEs in both uraemic and control plasma. Carbonyl stress was therefore thought to be a contributory factor in uraemia. 

Aortic samples, free of atherosclerotic lesions, were obtained from haemodialysis patients with end-stage renal disease and from age-matched controls.437 The media, but not the intima, proved positive immunohistochemically for pentosidine, which was observed along and between elastic fibres. In both groups, pentosidine-linked fluorescence was higher in elastin than in collagen, and the HPLC level of pentosidine was higher in the elastin from patients than in that from the controls. 

Yoshimura et al.43S have shown immunohistochemically with the 6D12 probe that reactive substances (CML) accumulate in the vascular walls of cardiac tissues in dialysis patients. A partial decrease in this accumulation followed renal transplantation. 

In human subjects with uraemia, the blood plasma levels of the a-oxoaldehydes, glyoxal, 2-oxopropanal, and ribosone increased greatly, but 3-erythrosone, 3-deoxy-erythrosone, 3-deoxyribosone, and 3-deoxyglucosone did not.440 

In peritoneal dialysis (PD), sterilisation of the fluid by heat leads to the presence of reactive carbonyl compounds, which have been incriminated in the progressive deterioration of the peritoneal membrane in long-term PD patients.441 Glutathione in conjunction with glyoxalase I, as well as aminoguanidine, counteracted the effect. 

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