Increased levels of advanced glycosylation end products in the kidney and liver from spontaneously diabetic Chinese hamsters determined by immunochemical assay

Increased levels of advanced glycosylation end products (AGEs) have been re ported in tissues in association with diabetes mellitus. Thus, we measured tissue AGE levels and detected an accumulation of AGEs in the kidney and li ver from spontaneously diabetic Chinese hamsters (CHAD) to determine the re lationship between AGEs and diabetes mellitus. Diabetic CHAD aged 12 to 13 months were studied together with age-matched nondiabetic CHAD. We used an AGE-specific noncompetitive enzyme-linked immunosorbent assay (ELISA) with polyclonal anti-AGE-bovine serum albumin (BSA) antibody to measure tissue A GE levels. The samples extracted from the kidney and liver obtained from di abetic and nondiabetic CHAD reacted with anti-AGE-BSA antibody. When the ab sorbance of standard AGE-BSA (0.1 mu g/mL) was expressed as 1 U, AGE levels in the kidney and liver from diabetic CHAD were significantly increased as compared with nondiabetic CHAD (kidney, 0.26 +/- 0.05 v 0.10 +/- 0.03 U/mu g protein, P < .01; liver, 0.20 +/- 0.03 v 0.09 +/- 0.02 U/mu g protein, P < .01). Positive AGE staining was observed in the renal cortex, especially in the tubules of diabetic CHAD, but little AGE staining was observed in t he glomerulus by the immunohistochemical study. AGE staining was diffuse in the hepatocytes. These AGE levels were significantly correlated with fasti ng plasma glucose and glycated hemoglobin (P < .01, respectively). In concl usion, we have confirmed that AGE structures were expressed in the kidney a nd liver from CHAD, and these AGE levels were increased in diabetic CHAD. A GE staining was observed in the renal tubules and hepatocytes. Tissue AGE l evels were positively correlated with glycemic control in CHAD. Copyright ( C) 2000 by W.B. Saunders Company.