Generation of sRAGE transgenic mice to study inflammaging.

The receptor for advanced glycation end products (RAGE) interacts with multiple ligands and transmits inflammatory signals from damage- and pathogen-associated molecular patterns (DAMPs and PAMPs) to cellular programs. RAGE shares ligands with another group of PRRs, Toll-like receptors. Such ligand-receptor promiscuity generates coordinated and complex signaling patterns that provide a basis for the development of multiple inflammaging diseases. Soluble RAGE (sRAGE) functions as a RAGE decoy that scavenges DAMP/PAMP ligands and dampens inflammatory signals. Epidemiological studies have shown that a lower level of circulating sRAGE is associated with metabolic syndromes including obesity, diabetes, hypertension, and subclinical brain disease. We hypothesize that an elevated level of circulating sRAGE serves to modulate systemic and low-grade chronical inflammation that often occurs in old age, and therefore minimizes the risk of inflammaing diseases. Consequently, a higher level of circulating sRAGE may improve the health-span of the organism. A newly generated transgenic mouse that has a higher level of circulating sRAGE and maintains normal expression levels of RAGE serves as a model to test this hypothesis.