CAT and diabetes mellitus: The level of malondialdehyde (MDA), a lipid peroxidation by‐product, was elevated in DM versus NM (0.37 ± 0.06 vs 0.29 ± 0.04, p < 0.05), while antioxidant enzyme activities, including superoxide dismutase (SOD) and catalase (CAT), were reduced (Figure2A–C).