Impact of body weight loss, body fat distribution and the nutritional status on the cortisol response to the Trier Social Stress Test (TSST) was investigated in this study. Fifty-one men (17 non-obese, 20 abdominally obese and 14 reduced obese) and 28 women (12 non-obese, 10 peripherally obese and 6 reduced obese) were subjected to the TSST in fed and fasted states. The TSST response was determined using salivary cortisol measurements.
View Article and Find Full Text PDFThe corticotropin-releasing factor (CRF) system is involved in numerous physiological and behavioral actions, including the regulation of energy balance. We examined the effects of the CRF(1) receptor antagonist, SSR125543, on energy balance and food deprivation-induced neuronal activation in obese rats. Lean (Fa/?) and obese (fa/fa) Zucker rats were treated orally with SSR125543 at a daily dose of 30 mg/kg for 21 days.
View Article and Find Full Text PDFObjective: Our goal was to assess the awakening cortisol response (ACR) in obese and reduced obese men and women.
Research Methods And Procedures: Fifty-one men (16 lean, 19 abdominally obese, and 16 reduced obese) and 31 women (12 lean, 10 subcutaneously obese, and 9 reduced obese) were selected to participate to this study. Strict ranges of BMI and waist circumference were used to select the participants.
The metabolic consequences of visceral obesity have been associated with amplification of glucocorticoid action by 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) in adipose tissue. This study aimed to assess in a rat model of diet-induced obesity the effects of pharmacological 11beta-HSD1 inhibition on the morphology and expression of key genes of lipid metabolism in intraabdominal adipose depots. Rats fed a high-sucrose, high-fat diet were treated or not with a specific 11beta-HSD1 inhibitor (compound A, 3 mg/kg.
View Article and Find Full Text PDFAm J Physiol Regul Integr Comp Physiol
April 2007
Agonists of the peroxisome proliferator-activated receptor gamma (PPARgamma) are insulin sensitizers that potently improve lipemia in rodents. This study aimed to determine the contribution of lipid secretion vs. clearance and the involvement of white adipose tissue (WAT) and brown adipose tissue (BAT) in the rapid hypolipidemic action of PPARgamma agonism.
View Article and Find Full Text PDFThe effects of the cannabinoid-1 receptor (CB(1)) antagonist rimonabant on energy metabolism and fasting-induced hypothalamic-pituitary-adrenal (HPA) axis and neuronal activation were investigated. Lean and obese Zucker rats were treated orally with a daily dose of 10 mg/kg rimonabant for 14 days. A comprehensive energy balance profile based on whole-carcass analyses further demonstrated the potential of CB(1) antagonists for decreasing energy gain through reducing food intake and potentially increasing brown adipose tissue thermogenesis.
View Article and Find Full Text PDFIn this study, we aimed to establish the mechanisms whereby peroxisome proliferator-activated receptor gamma (PPARgamma) agonism brings about redistribution of fat toward subcutaneous depots and away from visceral fat. In rats treated with the full PPARgamma agonist COOH (30 mg x kg(-1) x day(-1)) for 3 weeks, subcutaneous fat mass was doubled and that of visceral fat was reduced by 30% relative to untreated rats. Uptake of triglyceride-derived nonesterified fatty acids was greatly increased in subcutaneous fat (14-fold) and less so in visceral fat (4-fold), with a concomitant increase, restricted to subcutaneous fat only, in mRNA levels of the uptake-, retention-, and esterification-promoting enzymes lipoprotein lipase, aP2, and diacylglycerol acyltransferase 1.
View Article and Find Full Text PDFAcolbifene (ACOL) is a fourth-generation selective estrogen receptor modulator (SERM) that has strong and pure antiestrogenic properties toward estrogen-sensitive cancers, but improves energy and lipid metabolism in an estrogen-like fashion in rodent models. The aim of this study was to determine the potency of ACOL to reduce cholesterolemia in a dietary model of hypercholesterolemia and to establish its mechanisms of action. Intact and ovariectomized (OVX) female rats were treated for 3 weeks with ACOL, and serum cholesterol and liver determinants of cholesterol metabolism were assessed.
View Article and Find Full Text PDFThe cancer-preventing selective estrogen receptor modulator (SERM) acolbifene (ACOL) exerts a potent and pure antiestrogenic action in the mammary gland and uterus, yet it displays beneficial, estrogen-like actions on energy and lipid metabolism in rodents. The compound reduces food intake and strongly decreases cholesterolemia in rats fed a cholesterol-free diet. This study was designed to establish whether the anorectic effect of ACOL is involved in its cholesterol-lowering action, and whether the compound retains its ability to lower cholesterol concentrations in rats with diet-induced hypercholesterolemia.
View Article and Find Full Text PDFThis study aimed to identify the mechanisms of the hypolipidemic action of the selective estrogen receptor modulator (SERM) acolbifene (ACOL). Four weeks of treatment with ACOL reduced fasting and postprandial plasma triglycerides (TGs), an effect associated with lower VLDL-TG secretion rate (-25%), and decreased mRNA of microsomal triglyceride transfer protein (MTP; -29%). ACOL increased liver TG concentration (+100%) and amplified the feeding-induced increase in the master lipogenic regulators sterol-regulatory element binding protein-1a (SREBP-1a) and SREBP-1c.
View Article and Find Full Text PDFProg Neuropsychopharmacol Biol Psychiatry
December 2004
Previous studies showed that the antipsychotic drugs (APDs) sulpiride (SUL) and risperidone (RIS) induced body weight gain (BWG), hyperphagia, and increased serum levels of leptin, prolactin and corticosterone in female rats. Neither SUL nor RIS increased BWG or food intake (FI) in male rats. To further develop the animal model of APD-induced obesity, SUL (20 mg/kg/sc), RIS (0.
View Article and Find Full Text PDFAm J Physiol Regul Integr Comp Physiol
November 2004
Peroxisome proliferator-activated receptor gamma (PPARgamma) agonists improve insulin sensitivity and lipemia partly through enhancing adipose tissue proliferation and capacity for lipid retention. The agonists also reduce local adipose glucocorticoid production, which may in turn contribute to their metabolic actions. This study assessed the effects of a PPARgamma agonist in the absence of glucocorticoids (adrenalectomy, ADX).
View Article and Find Full Text PDFThe nuclear receptor peroxisome proliferator-activated receptor (PPAR)gamma modulates the expression of numerous genes involved in glucose and lipid homeostasis and plays a critical role in adipocyte differentiation. Expression of uncoupling protein (UCP)1, which is necessary for thermogenesis, is strongly stimulated by PPARgamma agonists but without an increase in energy expenditure. This study was designed to assess whether PPARgamma-induced UCP1 has any functional impact and, if so, whether it involves sympathetic activity.
View Article and Find Full Text PDFThe objective of the present study was to investigate the effects of the antiepileptic drug topiramate (TPM) on components of energy balance in lean and obese (ob/ob) mice in the presence or absence of leptin. Lean and ob/ob mice infused with either leptin or phosphate-buffered saline were treated with TPM for 7 days. TPM was mixed into the diet and administered at a dose of 60 mg/kg/day, whereas leptin was infused at the rate of 100 microg/kg/day using osmotic minipumps, which were subcutaneously implanted in the interscapular region.
View Article and Find Full Text PDFObesity and related metabolic disorders are important side effects of some antipsychotic drugs (APs). The currently available animal model of AP-induced bodyweight gain (BWG) in rats is based on administration of sulpiride (SUL). However, this model has important limitations.
View Article and Find Full Text PDFAm J Physiol Endocrinol Metab
February 2002
This study aimed to assess whether adipose lipoprotein lipase (LPL) becomes resistant to insulin in a nutritional model of resistance of glucose metabolism to insulin. Sprague-Dawley rats were fed for 4 wk chow or a purified high-sucrose, high-fat (HSHF) diet that induced overt insulin resistance. Rats were fasted for 24 h and then refed chow for 1, 3, or 6 h.
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