Serum levels of 1,5-anhydroglucitol and 1,5-anhydrofructose-derived advanced glycation end products in patients undergoing hemodialysis

Abstract

Background: 1,5-anhydroglucitol is a reduction product of 1,5-anhydrofructose. Circulating 1,5-anhydroglucitol is usually excreted by the kidneys and is reabsorbed via sodium-glucose co-transporter 4 in the renal tubules. In patients on hemodialysis, serum levels of 1,5-anhydroglucitol have been reported to be low; however, the underlying mechanism remains unclear. Methods: We measured inter-dialysis changes in the levels of serum 1,5-anhydroglucitol and 1,5-anhydrofructose-derived advanced glycation end products (AGEs) in 78 patients on hemodialysis. Serum levels of 1,5-anhydrofructose-derived AGEs were also determined using a polyclonal antibody. Results: The serum 1,5-anhydroglucitol level was decreased to as low as 2.0 μg/mL in the regular hemodialysis group; however, we could not verify changes in the serum 1,5-anhydroglucitol level during inter-dialysis days because of undetectable levels in 29 patients. The measured serum level of 1,5-anhydrofructose-derived AGEs was significantly increased in both patient groups. In addition, the 1,5-anhydrofructose-derived AGEs/1,5-anhydroglucitol ratio was higher in patients on hemodialysis than in controls. Conclusions: Accelerated glycation of 1,5-anhydrofructose is one possible mechanism by which serum 1,5-anhydroglucitol levels are lowered in patients on HD, and we propose that the 1,5-anhydrofructose-derived AGEs/1,5-anhydroglucitol ratio should be measured in clinical settings in which patients have low serum levels of 1,5-AG.