GLP1R and type 2 diabetes mellitus: Interestingly, sitagliptin, currently used for treating type 2 diabetic patients, has been found to be able to enhance circulating GLP-1 levels through inhibition of DPP-IV activity [35,36] which, in turn, provides cardiovascular protective effect probably through the anti-inflammatory and anti-atherosclerotic actions of GLP-1 [37].