Publications (6)15.86 Total impact
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Article: The atypical cannabinoid O-1602 stimulates food intake and adiposity in rats.
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ABSTRACT: Cannabinoids are known to control energy homeostasis. Atypical cannabinoids produce pharmacological effects via unidentified targets. We sought to investigate whether the atypical cannabinoid O-1602 controls food intake and body weight. The rats were injected acutely or subchronically with O-1602, and the expression of several factors involved in adipocyte metabolism was assessed by real-time polymerase chain reaction. In vivo findings were corroborated with in vitro studies incubating 3T3-L1 adipocytes with O-1602, and measuring intracellular calcium and lipid accumulation. Finally, as some reports suggest that O-1602 is an agonist of the putative cannabinoid receptor GPR55, we tested it in mice lacking GPR55. Central and peripheral administration of O-1602 acutely stimulates food intake, and chronically increases adiposity. The hyperphagic action of O-1602 is mediated by the downregulation of mRNA and protein levels of the anorexigenic neuropeptide cocaine- and amphetamine-regulated transcript. The effects on fat mass are independent of food intake, and involve a decrease in the expression of lipolytic enzymes such as hormone sensitive lipase and adipose triglyceride lipase in white adipose tissue. Consistently, in vitro data showed that O-1602 increased the levels of intracellular calcium and lipid accumulation in adipocytes. Finally, we injected O-1602 in GPR55 -/- mice and found that O-1602 was able to induce feeding behaviour in GPR55-deficient mice. These findings show that O-1602 modulates food intake and adiposity independently of GPR55 receptor. Thus atypical cannabinoids may represent a novel class of molecules involved in energy balance.Diabetes Obesity and Metabolism 03/2012; 14(3):234-43. · 3.38 Impact Factor -
Article: Perinatal overfeeding in rats results in increased levels of plasma leptin but unchanged cerebrospinal leptin in adulthood.
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ABSTRACT: To study the effect of perinatal programming and overfeeding on the hypothalamic control mechanisms of food intake in adult rats. Neonatal programming effects on body weight, food intake, central and peripheral leptin levels, hypothalamic neuropeptides, leptin receptors and central leptin responsiveness in adult rats. Plasma and cerebrospinal fluid (CSF) leptin levels were analyzed using radioimmunoassay. Neuropeptide mRNA levels were analyzed using in situ hybridization. Leptin receptor mRNA levels were analyzed using reverse transcriptase-polymerase chain reaction. Perinatally overfed rats growing up in small litters (SL) maintain their obese and hyperleptinemic phenotype in adulthood. However, leptin levels in CSF are abnormally low considering the plasmatic hyperleptinemia. In contrast to the already reported changes in perinatally overfed juvenile rats, perinatally overfed adult rats did not show any alteration in the expression of leptin receptor isoforms and evaluated neuropeptides. Moreover, SL adult rats showed a normal sensitivity regarding the inhibitory effect of intracerebroventricular leptin administration on food intake. Perinatal overfeeding does not induce alterations in either the anorectic response to central leptin administration or expression of leptin receptors and neuropeptides in adulthood. The leptin resistance to peripheral leptin in SL adult rats may be related to impaired leptin transport across the blood-brain barrier.International Journal of Obesity 03/2007; 31(2):371-7. · 4.69 Impact Factor -
Article: Effects of single or repeated intravenous administration of kisspeptin upon dynamic LH secretion in conscious male rats.
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ABSTRACT: The ability of kisspeptins, ligands of the G protein-coupled receptor 54, to potently elicit LH secretion is now undisputed. Yet, most of the pharmacological characterization of their gonadotropin-releasing effects has been conducted after intracerebral administration. In contrast, the effects of peripheral injection of kisspeptin remains less well defined. In this study, dynamic LH secretory responses to iv administration of kisspeptin-10 in different experimental settings are presented, and compared with those evoked by kisspeptin-52, using a protocol of serial blood sampling in conscious, freely moving male rats. LH responsiveness to peripheral administration of kisspeptin appeared extremely sensitive, as doses as low as 0.3 nmol/kg (0.1 microg/rat) evoked robust LH bursts, the magnitude of which was dose-dependent and apparently maximal in response to 3.0 and 30 nmol/kg kisspeptin-10. The ability of kisspeptin-10 to stimulate LH release was fully preserved, and even doubled in terms of relative increases, after short-term fasting despite suppression of prevailing LH levels. Repeated injections of kisspeptin-10 (four boluses, at 75-min intervals) evoked associated LH secretory pulses, the magnitude of which remained constant along the study period. Moreover, in this setting, in vivo LH responses to a terminal injection of GnRH were preserved, whereas basal and depolarization-induced GnRH release ex vivo was significantly enhanced. Finally, iv administration of kisspeptin-52 elicited dynamic LH responses analogous to that of kisspeptin-10; yet, their net magnitude and duration was slightly greater. In summary, we present in this study a series of experiments on the effects of systemic (iv) injection of single or repeated doses of kisspeptin upon dynamic LH secretion in conscious male rats. Aside from potential physiologic relevance, our present data might contribute to setting the basis for the rational therapeutic use of kisspeptin analogs in the pharmacological manipulation of the gonadotropic axis.Endocrinology 07/2006; 147(6):2696-704. · 4.46 Impact Factor -
Article: Inhibitory effects of eugenol and thymol on Penicillium citrinum strains in culture media and cheese.
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ABSTRACT: In the present work we studied the antifungal effect of eugenol and thymol on the growth and production of citrinin from Penicillium citrinum (NRRL 2274 and NRRL 2269) in culture media and in different Spanish cheeses (Arzúa-Ulloa, Cebreiro and San Simón). The rate of growth was assessed by measuring colony diameters and the production of citrinin was measured using a rapid semi-quantitative fluorometric technique confirmed by RP-HPLC. A stronger inhibitory effect of eugenol than thymol was evident. 200 microg/ml of eugenol in solid culture medium increased the lag time of growth up to 9 days, and decreased the rate of colony growth. In liquid medium, a complete inhibition of fungal growth was observed. By contrast, thymol in the liquid culture medium only affected the growth rate. In Arzúa-Ulloa cheese, 200 microg/ml of eugenol fully inhibited fungal growth, while in Cebreiro cheese no effect was observed for this compound. Regarding the capacity to inhibit mycotoxin production 100 microg/ml eugenol delayed citrinin production until the sixth day, after which a limiting effect persisted. In Arzúa-Ulloa cheese, no citrinin was detected at a concentration of 150 microg/ml of eugenol, but citrinin was detected after 5 days in the case of thymol at the same concentration. In Cebreiro cheese, neither eugenol nor thymol prevented the production of citrinin at the concentrations applied.International Journal of Food Microbiology 08/2001; 67(1-2):157-63. · 3.33 Impact Factor -
Article: Inhibitory effects of eugenol and thymol on Penicillium citrinum strains in culture media and cheese
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ABSTRACT: In the present work we studied the antifungal effect of eugenol and thymol on the growth and production of citrinin from Penicillium citrinum (NRRL 2274 and NRRL 2269) in culture media and in different Spanish cheeses (Arzúa-Ulloa, Cebreiro and San Simón). The rate of growth was assessed by measuring colony diameters and the production of citrinin was measured using a rapid semi-quantitative fluorometric technique confirmed by RP-HPLC. A stronger inhibitory effect of eugenol than thymol was evident. 200 μg/ml of eugenol in solid culture medium increased the lag time of growth up to 9 days, and decreased the rate of colony growth. In liquid medium, a complete inhibition of fungal growth was observed. By contrast, thymol in the liquid culture medium only affected the growth rate. In Arzúa-Ulloa cheese, 200 μg/ml of eugenol fully inhibited fungal growth, while in Cebreiro cheese no effect was observed for this compound. Regarding the capacity to inhibit mycotoxin production 100 μg/ml eugenol delayed citrinin production until the sixth day, after which a limiting effect persisted. In Arzúa-Ulloa cheese, no citrinin was detected at a concentration of 150 μg/ml of eugenol, but citrinin was detected after 5 days in the case of thymol at the same concentration. In Cebreiro cheese, neither eugenol nor thymol prevented the production of citrinin at the concentrations applied.International Journal of Food Microbiology. -
Article: Hypothalamic AMPK and fatty acid metabolism mediate thyroid regulation of energy balance
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ABSTRACT: Nature Medicine Vol.16, 1001 - 1008
