Receptor for advanced glycation endproducts (RAGE) and the complications of diabetes

Receptor for Advanced Glycation Endproducts (RAGE) is a multiligand member of the immunoglobulin superfamily of cell surface molecules with a diverse repertoire of ligands. These ligands include products of nonenzymatic glycation, the Advanced Glycation Endproducts (AGEs, enriched in the diabetic milieu), members of the S100/calgranulin family of proinflammatory mediators, beta-sheet fibrillar structures (characteristic of amyloid) and amphoterin (present at high levels in the tumor bed). Ligation of RAGE by its ligands upregulates expression of the receptor and triggers an ascending spiral of cellular perturbation due to sustained RAGE-mediated cellular activation. For example, in the setting of diabetes, a vascular environment rich in AGEs and S100/calgranulins accelerates atherogenesis in murine models, and this can be blocked by intercepting the interaction of ligands with RAGE. While RAGE is certainly not the cause of diabetes, it functions as a progression factor driving cellular dysfunction underlying the development of diabetic complications as the microenvironment becomes enriched in its ligands. Though further studies will be required to determine the importance of RAGE-mediated cellular activation to human chronic diseases, it represents a novel receptor-ligand system potentially impacting on a range of pathophysiologic conditions.