As for glutathione peroxidase (GPx) and catalase (CAT) enzymes, Colak et al. [75] detected reduced activity for both in patients with T2DM presenting with complications, whereas Kasznick et al. [63] observed diminishment for GPx activity in T2DM carriers presenting with neuropathy, while Moemen et al. observed a decrease in the activity of GPx in diabetic patients with proliferative neuropathy (PDR) [74]. This evidence concerns the gene CAT and neuropathy.