INS and type 2 diabetes mellitus: A similar GLP-1 effect in insulin secretion in humans was previously observed, where a synthetic human GLP-1 stimulated insulin secretion in T2D patients and normal subjects, while a diminished pancreatic glucagon release was observed [102], being the one of the first studies to point out whether GLP-1 receptor agonists could be used pharmacologically to reduce blood glucose levels in type-2 diabetic patients [102].