Nitration impairs copper/zinc superoxide dismutase activity

WHITE V; CAPOBIANCO E; HIGA R; MARTINEZ N; SOSA M; PUSTOVRH C; JAWERBAUM A

FREE RADICAL BIOLOGY AND MEDICINE

ELSEVIER SCIENCE INC

Año: 2010 vol. 4 p. 1407 - 1415

0891-5849

Nitrosative and oxidative stress are characteristic features of diabetic pregnancy. Nitrosylation-induced protein damage in the placenta leads to impaired blood flow and deficient feto-placental exchange in diabetic pregnancies. Cu/Zn superoxide dismutase (SOD) is an important enzyme in the defence mechanisms against oxidative damage. In this work, we studied the effect of nitric oxide and peroxynitrite on Cu/Zn SOD activity in rat placentas and evaluated whether Cu/Zn SOD is nitrosylated in the placenta from diabetic rats at midgestation. The placentas from control and neonatal streptozotocin-induced diabetic pregnant rats were studied on day 13.5 of gestation. Protein nitrosylation was evaluated by EIA, Cu/Zn SOD activity by inhibition of the epinephrine autoxidation, Cu/Zn SOD expression by western blot and specific nitrosylation by immunoprecipitation. We found higher levels of protein nitrosylation (p