SOD1 and diabetes mellitus: Previously, it was shown that diabetes induced oxidative stress and diminished antioxidant enzymes activities and capacity in the brain and hippocampus respectively.[3][21][22] However, Ramanathan et al. reported an increased SOD and CAT activities with no alteration in the GPX activity 72 hr after induction of diabetes.[23] On the contrary, they showed increased CAT and decreased GPX with no change in the SOD activity after one month of diabetes induction.