Melatonin counteracts changes in hypothalamic gene expression of signals regulating feeding behavior in high-fat fed rats

• Autores: Jiménez Ortega, Vanesa; Ríos Lugo, María J.; Cano Barquilla, Pilar; Cardinali, Daniel Pedro; Esquifino, Ana I.; Fernández Mateos, María P.; Spinedi, Eduardo J.
• Año de publicación: 2015
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: Preprint del artículo publicado en Hormone Molecular Biology and Clinical Investigation, Vol. 21, N° 3, 2015
• Materia: MELATONINA; GRASAS EN LA DIETA; ALIMENTACION; EXPRESION GENICA; NEUROPEPTIDO Y; PROOPIOMELANOCORTINA; PROLACTINA; LEPTINA; ADIPONECTINA; HIPOTALAMO MEDIO
• Institución: Pontificia Universidad Católica Argentina

Fil: Jiménez Ortega, Vanesa. Universidad Complutense. Facultad de Medicina. Departamento de Bioquímica y Biología Molecular III; España
Fil: Ríos Lugo, María J. Universidad Complutense. Facultad de Medicina. Departamento de Bioquímica y Biología Molecular III; España
Fil: Cano Barquilla, Pilar. Universidad Complutense. Facultad de Medicina. Departamento de Bioquímica y Biología Molecular III; España
Fil: Cardinali, Daniel P. Pontificia Universidad Católica Argentina. Facultad de Ciencias Médicas. Instiuto de Investigaciones Biomédicas; Argentina
Fil: Cardinali, Daniel P. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Esquifino, Ana I. Universidad Complutense. Facultad de Medicina. Departamento de Bioquímica y Biología Molecular III; España
Fil: Fernández Mateos, Pilar. Universidad Complutense. Facultad de Medicina. Departamento de Biología Celular; España
Fil: Spinedi, Eduardo J. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Spinedi, Eduardo J. Universidad Nacional de La Plata. Centro de Endocrinología Experimental y Aplicada; Argentina
Abstract: Background: Previous studies indicate that the administration of melatonin caused body weight and abdominal visceral fat reductions in rodent models of hyperadiposity. The objective of the present study performed in high-fat fed rats was to evaluate the activity of melatonin on gene expression of some medial basal hypothalamus (MBH) signals involved in feeding behavior regulation, including neuropeptide Y (NPY), proopiomelanocortin (POMC), prolactin-releasing peptide (PrRP), leptin- and insulinreceptors (R) and insulin-R substrate (IRS)-1 and -2. Blood levels of leptin and adiponectin were also measured. Methods: Adult Wistar male rats were divided into four groups (n= 16/group): (i) control diet (3 % fat); (ii) high-fat (35 %) diet; (iii) high-fat diet + melatonin; (iv) control diet + melatonin. Rats had free access to high-fat or control chow and one of the following drinking solutions: (a) tap water; (b) 25 μg/mL of melatonin. Results: After 10 weeks, the high-fat fed rats showed augmented MBH mRNA levels of NPY, leptin-R, PrRP, insulin-R, IRS-1 and IRS-2. The concomitant administration of melatonin counteracted this increase. Feeding of rats with a high-fat diet augmented expression of MBH POMC gene through an effect insensitive to melatonin treatment. The augmented levels of circulating leptin and adiponectin seen in high-fat fed rats were counteracted by melatonin as was the augmented body weight: melatonin significantly attenuated body weight increase in high-fat fed rats without affecting chow or water consumption. Melatonin augmented plasma leptin and adiponectin in control rats. Conclusions: The results indicate that an effect on gene expression of feeding behavior signals at the CNS may complement a peripheral rise of the energy expenditure produced by melatonin to decrease body weight in high-fat fed rats