Sex-related differences in the effects of high-fat diets on DHEA-treated rats.

Several studies have investigated the beneficial effects of dehydroepiandrosterone (DHEA) on lipid and glucose metabolism. However, many of these studies are inconclusive about the effects of DHEA administration on metabolic disorders, and there appear to be sex-related differences in the effects of DHEA treatment. Few animal studies have addressed the effects of DHEA on diet-induced metabolic disorders.

Effects of dehydroepiandrosterone (DHEA) and lactate on glucose uptake in the central nervous system.

Dehydroepiandrosterone (DHEA) prevents brain aging, enhances the cerebral metabolism and interacts with energy substrates. The interaction between lactate and DHEA on glucose uptake and lactate oxidation by various nervous structures was investigated and results demonstrate that the 2-(14)C-deoxiglucose (2-(14)C-Dglucose) uptake was stimulated by 10mM lactate in the hypothalamus and olfactory bulb, inhibited in the cerebral cortex and cerebellum, and unaffected in the hippocampus. We also show that, in both the cerebral cortex and hypothalamus, (14)C-lactate oxidation was higher than (14)C-glucose oxidation (p≤0.

Dehydroepiandrosterone improves hepatic antioxidant reserve and stimulates Akt signaling in young and old rats.

This study examined, in the liver of young and old (3- and 24-month-old, respectively) healthy Wistar rats, the in vivo effect of dehydroepiandrosterone (DHEA) (10mg/kg body weight) administered subcutaneously for 5 weeks. Reduced (GSH) and oxidized (GSSG) glutathione levels, glucose-6-phosphate dehydrogenase (G6PDH), glutathione-S-transferase (GST), glutathione peroxidase (GPx) and catalase (CAT) activities, hydrogen peroxide concentration, GST and p-Akt/Akt immunocontent ratio were assessed in hepatic tissue. DHEA treatment significantly increased total glutathione content (17%) and GSH (22%) in 3- and 24-month-old treated groups when compared to control groups.

Redox imbalance influence in the myocardial Akt activation in aged rats treated with DHEA.

This study examined, in young and old (3 and 24 month-old, respectively) healthy Wistar rats, the in vivo effect of DHEA (10 mg/kg body weight) administered subcutaneously for 5 weeks. Reduced (GSH) and oxidized (GSSG) glutathione levels, glucose-6-phosphate dehydrogenase (G6PDH), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and thioredoxin (Trx) reductase activities, hydrogen peroxide steady-state concentration and Nrf2, GST, Trx-1, Akt and p-Akt expressions were assessed in heart tissue. DHEA treatment significantly increased GST activity in 3 and 24 month-old treated groups.

Increased resistance to hydrogen peroxide-induced cardiac contracture is associated with decreased myocardial oxidative stress in hypothyroid rats.

The purpose of this study was to determine whether decreased oxidative stress would increase the resistance to cardiac contracture induced by H(2)O(2) in hypothyroid rats. Male Wistar rats were divided into two groups: control and hypothyroid. Hypothyroidism was induced via thyroidectomy.

DHEA effects on myocardial Akt signaling modulation and oxidative stress changes in aged rats.

The secretion of DHEA-synthesized mainly in the adrenal cortex-increases in the postnatal aging, peaks in the twenties and decreases with age afterwards. Exogenous DHEA can exert a dual effect depending on dose and on tissue. Akt is a serine/threonine kinase whose activity has been seen as an interventional approach for cardiomyopathic damage resulting from aging changes.