Fructose overload modifications in oxidative metabolism and corticosterone production in rat epididymal adipose tissue

PRINCE, PAULA DENISSE; GEREZ, ESTEFANIA; HOCHT, CHRISTIAN; POLIZIO, ARIEL; FRAGA, CESAR G; MAYER, MARCOS A; GALLEANO, MÓNICA; CARRANZA, ANDREA

Davis, California

Congreso; Oxidants and Antioxidants in Biology: Redox Medicine and Nutrition; 2016

Oxigen Club of California

Fructose overload has been shown to produce relevant metabolic effects in mammals This study was focused in the modifications induced on rat epididymal white adipose tissue (EWAT) machinary involved in oxidative metabolism and glucocorticoid synthesis. Male Sprague-Dawley rats received fructose 10% P/V in the tap water (fructose fed group = F) or tap water (control group = C) for 7 weeks as a model of metabolic syndrome (MS). At the end of the treatment F animals showed significant increases in plasma triglycerides and insulin levels as well as blood pressure respect to C group. Corticosterone plasma levels resulted 1.1 fold increase in F rats. Ex vivo EWAT superoxide anion production showed and increment of 3.9 fold in F respect to C in association with signifficant increases in NOX subunits expression (24%, 33% y 53% for p22, p47 and gp91 respectively). Among the oxidative stress markers determined, only EWAT GSH levels were affected, showing a decrease of 55% in F respect to C. Microsomal fraction of EWAT was obtained to determined aspects related with corticosterone synthesis. 11-beta hydroxysteroid dehydrogenase 1 (11 beta-HSD) and hexose-6-phosphate deshydrogenase (H6PD) activities were higherer in F respect to C in paralels with levels of their protein expression (1.0 and 2.5 fold increase for 11 beta-HSD and H6PD respectively). Additionaly, microsomal NADPH content was 62% higher in F rats respect to C rats. These results support that fructose overload modifies EWAT becoming a potential source of superoxide anion and/or corticosterone