IAPP and type 2 diabetes mellitus: Proline substitution at positions 25 (Ala), 28 (Ser) and 29 (Ser) of human amylin decreases the stability of its β-sheet structure [58], and pramlintide, which is clinically used to treat patients with type 1 diabetes and T2D, is human amylin containing these substitutions [59] (Figure 3).