GCG and Hyperglycemia: Interestingly, the effects of GLP-1 and GLP-1 analogs, as well as of DPP4 inhibitors, that act by inhibiting the cleavage of endogenous GLP-1, are not limited to the control of hyperglycemia, but involve several other tissues and functions (Sortino et al., 2013; Gallwitz, 2014).