Isyaku U. Yarube, Joseph O. Ayo, Rabiu A. Magaji, Isma’il A. Umar Insulin-induced oxidative stress in the brain is nitric oxide-dependent  Isyaku U. Yarube, Joseph O. Ayo, Rabiu A. Magaji, Isma’il A. Umar  Pathophysiology  DOI: 10.1016/j.pathophys.2019.02.003 Copyright © 2019 Elsevier B.V. Terms and Conditions

Fig. 1 Nitric oxide level in brain homogenates of control and treated mice. (Mean ± S.E.M, n = 5) *Significantly higher (P <  0.05) than in the other groups. Pathophysiology DOI: (10.1016/j.pathophys.2019.02.003) Copyright © 2019 Elsevier B.V. Terms and Conditions

Fig. 2 Malondialdehyde level in brain homogenates of control and treated mice. (Mean ± S.E.M, n = 5) *Significantly higher (P <  0.05) than in the other groups. Pathophysiology DOI: (10.1016/j.pathophys.2019.02.003) Copyright © 2019 Elsevier B.V. Terms and Conditions

Fig. 3 Glutathione peroxidase activity in brain homogenates of control and treated mice. (Mean ± S.E.M, n = 5) *Significantly lower (P <  0.05) than in the other groups. Pathophysiology DOI: (10.1016/j.pathophys.2019.02.003) Copyright © 2019 Elsevier B.V. Terms and Conditions

Fig. 4 Mechanism through which insulin increases oxidative stress in the brain. Note that the ability of insulin to induce oxidative stress is NO-dependent (blocked by NOS inhibitors) (dashed arrow) as demonstrated in this study. NO (nitric oxide), MDA (malonedialdehyde), GPx (glutathione peroxidase), NO (nitrite radical), ONOO− (peroxinitrite), O2 (superoxide), H2O2 (hydrogen peroxide), ↑ and ↓ (increase and decrease in NO, MDA and GPx, respectively). Pathophysiology DOI: (10.1016/j.pathophys.2019.02.003) Copyright © 2019 Elsevier B.V. Terms and Conditions