title: Appetite regulation: the central role of melatonin in Danio rerio.
abstract: Melatonin is the hormonal mediator of photoperiodic information to the central nervous system in vertebrates and allows the regulation of energy homeostasis through the establishment of a proper balance between energy intake and energy expenditure. The aim of this study was to evaluate the role of melatonin in appetite central control analyzing the involvement of this hormone in the regulation of feeding behavior in the zebrafish Danio rerio. For this purpose, the effect of two different melatonin doses (100nM and 1μM) administered for 10 days, via water, to zebrafish adults was evaluated at both physiological and molecular level and the effect of melatonin was considered in relation to the most prominent systems involved in appetite regulation. For the first time, in fact, melatonin control of food intake by the modulation of leptin, MC4R, ghrelin, NPY and CB1 gene expression was evaluated. The results obtained indicate that melatonin significantly reduces food intake and the reduction is in agreement with the changes observed at molecular level. A significant increase in genes codifying for molecules involved in feeding inhibition, such as leptin and MC4R, and a significant reduction in the major orexigenic signals including ghrelin, NPY and CB1 are showed here. Taken together these results support the idea that melatonin falls fully into the complex network of signals that regulate food intake thus playing a key role in central appetite regulation.
authors.affiliation: Dipartimento di Scienze del Mare, Università Politecnica delle Marche, Via Brecce Bianche 60131, Ancona, Italy.
authors.forename: Chiara Carla
authors.initials: CC
authors.lastname: Piccinetti
authors.forename: Beatrice
authors.initials: B
authors.lastname: Migliarini
authors.forename: Ike
authors.initials: I
authors.lastname: Olivotto
authors.forename: Giuliana
authors.initials: G
authors.lastname: Coletti
authors.forename: Adolfo
authors.initials: A
authors.lastname: Amici
authors.forename: Oliana
authors.initials: O
authors.lastname: Carnevali
mesh_terms: D000818:Animals; D001069:Appetite Regulation / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000187:drug effects / Q000502:physiology; D005786:Gene Expression Regulation / Q000187:drug effects; D054439:Ghrelin / Q000235:genetics / Q000378:metabolism; D020738:Leptin / Q000235:genetics / Q000378:metabolism; D008550:Melatonin / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology*; D009478:Neuropeptide Y / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D043884:Receptor, Cannabinoid, CB1 / Q000235:genetics / Q000378:metabolism; D044105:Receptor, Melanocortin, Type 4 / Q000235:genetics / Q000378:metabolism; D015027:Zebrafish / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D054439:Ghrelin; D020738:Leptin; D009478:Neuropeptide Y; D012333:RNA, Messenger; D043884:Receptor, Cannabinoid, CB1; D044105:Receptor, Melanocortin, Type 4; D029961:Zebrafish Proteins; C461479:mc4r protein, zebrafish; D008550:Melatonin