Dissociation between urinary pyrraline and pentosidine concentrations in diabetic patients with advanced nephropathy.

Abstract It has been reported that the concentrations of both pyrraline and pentosidine, well-characterized advanced glycation end products, are increased in the urine of diabetic patients. To determine factors that influence the urinary excretion of pyrraline or pentosidine, we compared pyrraline or pentosidine concentrations with glycemic-control indexes, urinary albumin excretion, and urinary β2-microglobulin in patients with type 2 diabetes. The study was conducted in 39 age-matched healthy control subjects and 50 diabetic patients, including 22 patients with normoalbuminuria, 15 with microalbuminuria, and 13 with macroalbuminuria. Both urinary pyrraline and pentosidine were measured in early-morning urine specimens with the use of high-pressure liquid chromatography. The urinary pentosidine concentration was significantly higher in diabetic patients than in control subjects ( P P 1c (HbA 1c ) and the preceding year's mean HbA 1c were lower in patients with macroalbuminuria than in those with normoalbuminuria or microalbuminuria. Urinary pyrraline, but not pentosidine, showed a significantly positive correlation with the preceding year's mean HbA 1c (P P