Sucrose-induced insulin resistance is accompanied by morphologic and functional changes in the adrenal cortex of the rat

MARTINEZ CALEJMAN, CAMILA; ASTORT, FRANCISCO; REPETTO, ESTEBAN M.; SANCHEZ, ROCIO; DI GRUCCIO, JUAN MARTIN; CYMERYNG, CORA BEATRIZ; ARIAS, PABLO

Estocolmo

Congreso; 46th EASD Annual Meeting; 2010

European Association for the Study of Diabetes

Hyperactivation of the hypothalamic-pituitary-adrenal (HPA) axis has been widely described in both human and animals showing insulin resistance (IR). However, a direct effect of the biochemical abnormalities that characterize this syndrome (e.g. elevated plasma glucose, serum insulin and free fatty acid levels, hypertriglicerydemia and oxidative stress) on adrenal function has not been elucidated yet. In this study we assesed the effect of a sucrose-enriched diet (SED) on adrenocortical structure and function (corticosterone secretion) in rats.Materials and methods:Male Wister rats were fed a sucrose enriched diet (SED, drinking water contaning 30% w/v of sucrose) up to 12 weeks. Rosiglitazone (4mg/kg, orally and daily) was administered throughout the duration of the sucrose treatment in a group of animals. Protein levels of different isoforms of nitric oxide synthase (NOS), phosphorylated Akt and cyclooxygenase 2 (COX-2) were analyzed by immunoblot while mRNA levels of steroidogenic acute regulatory protein (StAR) and the macrophage marker F4/80 were assesed by semiquantitative RT-PCR. Steroid levels were determined by RIA. Sudan III staining was performed on adrenocortical slices previously fixed in 4% formaldehyde. Results: As compared to controls, rats under SED for 7 weeks showed higher fasting plasma glucose (74 ± 5 and 130 ± 6 mg/dl; p