Binding of receptor for advanced glycation end products (RAGE) ligands is not sufficient to induce inflammatory signals: lack of activity of endotoxin-free albumin-derived advanced glycation end products

Diabetologia. 2004 May;47(5):844-52. doi: 10.1007/s00125-004-1392-9. Epub 2004 May 1.


Aims/hypothesis: Activation of the receptor for advanced glycation end products (RAGE) reportedly triggers cellular responses implicated in the pathogenesis of diabetes, such as increasing vascular cell adhesion molecule-1 (VCAM-1) expression on vascular endothelial cells and inducing TNF-alpha secretion by mononuclear cells. The objective of this study was to evaluate whether RAGE binding affinity of AGE-BSAs and cellular activation correlate.

Methods: To produce AGEs with varying glycation, bovine albumin AGEs were prepared with 500 mmol/l of glucose, fructose or ribose at times of incubation from 1 to 12 weeks. In addition, AGE-BSA was generated using either glyoxylic acid or glycolaldehyde. Cellular binding of the AGE-BSAs and the effect on endothelial cell VCAM-1 expression were studied in RAGE-expressing human microvascular endothelial cell line-4 cells. Induction of TNF-alpha secretion was assessed using RAGE-expressing human peripheral blood mononuclear cells (PBMCs).

Results: Cellular binding of the different AGE preparations correlated well with RAGE affinity. Interestingly, we found that the AGE preparations, which were essentially endotoxin free (< or =0.2 ng/mg protein), were incapable of inducing VCAM-1 or TNF-alpha secretion regardless of RAGE binding affinity, AGE concentration or incubation time. In contrast, the reported RAGE ligand S100b was confirmed to induce VCAM-1 expression on endothelial cells and TNF-alpha secretion by PBMCs after 24 h of treatment.

Conclusions/interpretation: The results of this study suggest that AGE modification and high RAGE binding affinity are not sufficient to generate pro-inflammatory signalling molecules. Thus, RAGE binding affinity of AGE-BSAs does not seem to correlate with cellular activation. Our findings using AGEs with strong RAGE-binding properties indicate that AGEs may not uniformly play a role in cellular activation.

MeSH terms

  • Animals
  • Cattle
  • Cells, Cultured
  • Endothelium, Vascular / physiology*
  • Glycation End Products, Advanced / metabolism*
  • Humans
  • Infant, Newborn
  • Inflammation / physiopathology*
  • Kinetics
  • Leukocytes, Mononuclear / physiology*
  • Male
  • Microcirculation
  • Protein Binding
  • Receptor for Advanced Glycation End Products
  • Receptors, Immunologic / metabolism*
  • Serum Albumin, Bovine / metabolism*
  • Skin / blood supply


  • Glycation End Products, Advanced
  • Receptor for Advanced Glycation End Products
  • Receptors, Immunologic
  • advanced glycation end products-bovine serum albumin
  • Serum Albumin, Bovine