Levels of 8-hydroxy-deoxyguanosine (8-OHdG), 3-nitrotyrosine (3-NT), glutathione (GSH), superoxide dismutase (SOD) and Interleukin-6 (IL-6) were estimated before and after 2 weeks of insulin therapy in normal group (NC) and type 2 diabetic (DM) with normal albuminuria (NA), microalbuminuria (MA) and clinical albuminuria (CA). This evidence concerns the gene SOD1 and diabetes mellitus.