CEFYBO   02669
CENTRO DE ESTUDIOS FARMACOLOGICOS Y BOTANICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
HPA Dysfunction in Streptozotocin-Diabetic Rats: Effect of Lipoic Acid and α-Tocopherol Treatment
Autor/es:
REPETTO EM; BONELLI AL; SANCHEZ R; MERCAU ME; ARIAS P; CYMERYNG CB
Lugar:
Chicago
Reunión:
Congreso; Endocrine Society's 96th Annual Meeting and Expo; 2014
Institución organizadora:
Endocrine Society
Resumen:
Abstract: Background and aims: We previously demonstrated that streptozotocin-induced (STZ) diabetes entails an increase in oxidative stress in rat adrenocortical tissue, as well as an altered corticosterone secretion. We also showed that systemic antioxidant treatment normalized these changes. Present experiments were designed in order to test the hypothesis that STZ-induced oxidative stress might modify corticosterone release by affecting pituitary ACTH secretion. With this purpose, we analyzed plasma ACTH levels and glucocorticoid secretion patterns in STZ treated rats with or without lipoic acid (LA) or α-tocopherol (αT) treatment The effect of antioxidant treatment on these parameters was also assessed in non-diabetic animals. Materials and methods: Male Wistar rats (220-240g BW) were randomly assigned to the following groups: CON (control), STZ (two injections of 40 mg/kg STZ separated by 48 h), LA (90 mg/kg ip every 48 h), αT (200 mg/kg po), STZ-LA or STZ-αT (where LA or αT treatment were initiated immediately after the confirmation of STZ-induced hyperglycemia). After 4 weeks, all animals were sacrificed and plasma ACTH and serum corticosterone levels (basal and ACTHstimulated) were measured. In adrenal cortex homogenates lipid peroxidation (as TBARS), as well as the expression levels of CYP11A1 and MC2R (RT-qPCR) were evaluated. Results: Antioxidants had no effect on fasting plasma glucose levels in STZ animals. Neither αT nor LA prevented the decrease in ACTH circulating levels detected in STZ-treated rats (CON: 40.9±6.8 p