INS and diabetes mellitus: Type 2 diabetes mellitus (T2DM) represents a group of heterogeneous metabolic diseases encompassing a wide variety of pathogenetic mechanisms ranging from abnormalities related to glucose-stimulated insulin secretion [1], [2], insulin resistance [3], [4], endoplasmic reticulum stress-induced β cell apoptosis [5] and inflammatory-mediated lesions of the target organ [6]–[10].