GCG and obesity due to melanocortin 4 receptor deficiency: Although correlative data should be interpreted cautiously, GLP-1 agonists have previously been shown to attenuate AGE induced RAGE expression in a small number of in-vivo and in-vitro settings [14,15], leading several researchers to postulate that the GLP-1-AGE-RAGE axis may be important in diabetes complications [37,38] and obesity-related metabolic asthma [39].