Long-Term Administration of Angiotensin (1–7) to db/db Mice Reduces Oxidative Stress Damage in the Kidneys and Prevents Renal Dysfunction

Figure 5

eNOS phosphorylation and NOX-4 expression in the kidneys from animals treated for 16 weeks. Levels of eNOS phosphorylated on Ser1177 (activating phosphorylation) and eNOS phosphorylated on Thr495 (deactivating phosphorylation), and NOX-4, a member of NADPH oxidase family, were assessed using immunohistochemistry in animals treated for 16 weeks. Representative images of kidney cortex taken at 40x magnification are shown in (a). Levels of both phosphorylation forms were increased in db/db mice from the control group. The extent of phosphorylation on Ser1177 was also increased in the diabetic animals treated with A(1–7) (b), whereas levels of phosphorylation on Thr495 were decreased in this group (c). The extent of staining for NOX-4 was increased in the diabetic animals from the control group compared to nondiabetic mice. Treatment with A(1–7) reduced the levels of NOX-4 in the kidneys of diabetic mice (d). (hzg: heterozygous; animals per group; , , , and ) Calculated using one-way ANOVA; plotted as mean with SEM.

(a)

(b)

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