RAGE: a new pleiotropic antagonistic gene?

Advanced glycation end products (AGEs) are the result of a nonenzymatic reaction of reducing sugars with primary amino groups of proteins (Maillard reaction). They accumulate in various tissues in the course of aging. Because AGEs induce protein cross-links and oxidative stress (radicals) within cells and tissues, they have been implicated in the development of many degenerative diseases. Binding of AGEs to receptors like RAGE induces the release of profibrotic cytokines, such as TGF-beta or proinflammatory cytokines, such as TNF-alpha or IL-6. AGE inhibitors or breakers, such as aminoguanidine or ALT-711, inhibit the age-induced heart hypertrophy or stiffness of the large arteries. On the other hand, little is known about the physiological role of RAGE as the receptor of AGEs. Investigations about the expression of RAGE in lung tissue and lung tumors may give a hint for such a role.