PON2 and diabetes mellitus: The aim of this paper is to review the pathophysiological role of paraoxonases: PON-1, PON-2 and PON-3, in the development of diseases related to aging and lipid peroxidation, mainly in atherosclerosis and cardiovascular diseases, diabetes mellitus, neurodegenerative diseases (Alzheimer’s disease, Parkinson disease, multiple sclerosis) and cancer.