Association Between Serum Levels of the Soluble Receptor (sRAGE) for Advanced Glycation Endproducts (AGEs) and their Receptor (RAGE) in Peripheral Blood Mononuclear Cells of Children with Type 1 Diabetes Mellitus

Aim: The binding of AGEs to RAGE is involved in diabetic vascular complications. We studied sRAGE levels and RAGE protein expression (P) together with N-carboxymethyl lysine (CML), a major AGE, in 74 patients with type I diabetes mellitus (DM1) and 43 healthy (C) children. Methods: sRAGE and CML levels were determined by ELISA and RAGE P was evaluated in mononuclear cells by Western immunoblotting. Results: Serum sRAGE was higher in DM1 than in C (1430 +/- 759 vs 1158 +/- 595 pg/ml, p = 0.047), inversely correlated to diabetes duration (r = -0.265, p = 0.037) and directly correlated to LDL-cholesterol levels (r = 0.224, p = 0.039). Diabetes duration correlated independently with sRAGE (p = 0.034). Circulating CML levels were not significantly different between DM1 and C groups (3.51 +/- 1.49 vs 3.59 +/- 1.83 ng/ml, p > 0.05) and RAGE P was lower in DM1 than in C (61 +/- 46 vs 102 +/- 63%, p = 0.0001). Conclusions: Increased serum sRAGE in children with DM1 may provide temporary protection against cell damage and may be sufficient to eliminate excessive circulating CML.