IAPP and Parkinson disease: Some classes, as tetracyclines and polyphenols, have the capability to interfere with the aggregation of several unrelated amyloidogenic proteins, such as α-synuclein (associated to Parkinson’s disease), islet amyloid polypeptide (IAPP, associated to type-2 diabetes), and it is likely they share partially overlapping mechanisms of action (Andrich and Bieschke, 2015; Giorgetti et al., 2018; Martinez et al., 2020).