INS and Insulin resistance: Notably, while impaired insulin action in peripheral tissue—the so-called “insulin resistance”—remains fairly constant as the disease progresses, β-cell function worsens continuously with time in diabetic patients, as a consequence of the persisting exposure to damaging factors, such as high glucose concentrations (glucose toxicity), increased levels of circulating free fatty acids (lipotoxicity), and proinflammatory cytokines (chronic inflammation) [2–5].