The lowering of DPP-4 levels observed in the present study is in accordance with the maintained GLP-1 levels and may be specific to GLP-1RA exenatide, since liraglutide, with its beneficial metabolic effects, has been shown to suppress endogenous total GLP-1 in adults with obesity (18). Here, DPP4 is linked to obesity due to melanocortin 4 receptor deficiency.