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Sanetra AM, Palus-Chramiec K, Chrobok L, Jeczmien-Lazur JS, Klich JD, Lewandowski MH. Proglucagon signalling in the rat Dorsomedial Hypothalamus - Physiology and high-fat diet-mediated alterations. Mol Cell Neurosci 2023; 126:103873. [PMID: 37295578 DOI: 10.1016/j.mcn.2023.103873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/24/2023] [Accepted: 06/06/2023] [Indexed: 06/12/2023] Open
Abstract
A relatively new pharmacological target in obesity treatment has been the preproglucagon (PPG) signalling, predominantly with glucagon-like peptide (GLP) 1 receptor agonists. As far as the PPG role within the digestive system is well recognised, its actions in the brain remain understudied. Here, we investigated PPG signalling in the Dorsomedial Hypothalamus (DMH), a structure involved in feeding regulation and metabolism, using in situ hybridisation, electrophysiology, and immunohistochemistry. Our experiments were performed on animals fed both control, and high-fat diet (HFD), uncovering HFD-mediated alterations. First, sensitivity to exendin-4 (Exn4, a GLP1R agonist) was shown to increase under HFD, with a higher number of responsive neurons. The amplitude of the response to both Exn4 and oxyntomodulin (Oxm) was also altered, diminishing its relationship with the cells' spontaneous firing rate. Not only neuronal sensitivity, but also GLP1 presence, and therefore possibly release, was influenced by HFD. Immunofluorescent labelling of the GLP1 showed changes in its density depending on the metabolic state (fasted/fed), but this effect was eliminated by HFD feeding. Interestingly, these dietary differences were absent after a period of restricted feeding, allowing for an anticipation of the alternating metabolic states, which suggests possible prevention of such outcome.
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Affiliation(s)
- A M Sanetra
- Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Gronostajowa Street 9, 30-387 Krakow, Poland.
| | - K Palus-Chramiec
- Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Gronostajowa Street 9, 30-387 Krakow, Poland
| | - L Chrobok
- Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Gronostajowa Street 9, 30-387 Krakow, Poland; School of Physiology, Pharmacology, and Neuroscience, University of Bristol, University Walk, Biomedical Sciences Building, Bristol BS8 1TD, UK
| | - J S Jeczmien-Lazur
- Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Gronostajowa Street 9, 30-387 Krakow, Poland
| | - J D Klich
- Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Gronostajowa Street 9, 30-387 Krakow, Poland; Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle Street 10, 13125 Berlin, Germany
| | - M H Lewandowski
- Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Gronostajowa Street 9, 30-387 Krakow, Poland.
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2
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Huerta C, Meza E, Caba-Flores MD, Morales T, Paredes RG, Caba M. Activation of the central but not the medial and cortical amygdala during anticipation for daily nursing in the rabbit. Brain Res 2023; 1809:148341. [PMID: 37001722 DOI: 10.1016/j.brainres.2023.148341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/11/2023] [Accepted: 03/22/2023] [Indexed: 04/03/2023]
Abstract
Rabbits have remarkable nursing behavior: after parturition, does visit daily their pups for nursing only once with circadian periodicity. Before the nursing events, they present increased activity and arousal, which shift according to the timing of scheduled nursing, either during the day or night. Brain areas related to maternal behavior and neuroendocrine cells for milk secretion are also entrained. The daily return of the doe for nursing at approximately the same hour suggests a motivational drive with circadian periodicity. Previously, we reported the activation of the mesolimbic system at the time of nursing, but not 12 h before that. Aiming at a better understanding of the mechanism of this anticipatory behavior, we explored the participation of the limbic regions of the amygdala and the bed nucleus of the stria terminalis, as well as the possible activation of the hypothalamic-pituitaryadrenal axis, specifically the corticotropin-releasing factor cells in the hypothalamic paraventricular nucleus of does at different times before and after nursing. The medial and cortical amygdala, the bed nucleus of the stria terminalis, and corticotropin cells showed activation only after nursing. However, the central amygdala was also activated before nursing. We conclude that the medial and the cortical amygdala form part of the afferent olfactory pathway for entrainment, and the central amygdala participates in the anticipatory motivational circuit of the control of periodic nursing. The lack of activation of corticotropin cells before nursing is consistent with the possible harmful effects of the doe's high glucocorticoid levels on the developing pups.
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Affiliation(s)
- César Huerta
- Centro de Investigaciones Biomédicas (CIB), Universidad Veracruzana, Mexico
| | - Enrique Meza
- Centro de Investigaciones Biomédicas (CIB), Universidad Veracruzana, Mexico
| | - Mario Daniel Caba-Flores
- Departamento de Bioquímica y Medicina Molecular, Facultad de Medicina, Universidad Autónoma de Nuevo León, Mexico
| | - Teresa Morales
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, UNAM, Mexico
| | - Raúl G Paredes
- Instituto de Neurobiología and Escuela Nacional de Estudios Superiores, Unidad, Juriquilla, UNAM, Mexico
| | - Mario Caba
- Centro de Investigaciones Biomédicas (CIB), Universidad Veracruzana, Mexico.
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3
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Sanetra AM, Palus-Chramiec K, Chrobok L, Lewandowski MH. Electrophysiological complexity in the rat dorsomedial hypothalamus and its susceptibility to daily rhythms and high-fat diet. Eur J Neurosci 2022; 56:4363-4377. [PMID: 35796742 DOI: 10.1111/ejn.15759] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 06/10/2022] [Accepted: 06/10/2022] [Indexed: 12/30/2022]
Abstract
The dorsomedial hypothalamus (DMH) in amongst the most important brain structures involved in the regulation of feeding behaviour and metabolism. In contrast to other hypothalamic centres, its main role is related to the circadian rhythmicity of food intake and energy homeostasis; both reported to be disrupted in obesity. In modern world, overweight and obesity reached global epidemic proportions. Thus, not only is it important to study their negative implications but also the mechanism responsible for their development. Here, we exposed rats to short-term (2-4 weeks) high-fat diet (HFD)-not long enough to induce obesity. Next, we performed electrophysiological patch-clamp recordings ex vivo from neurons in the DMH either during the day or at night. Our results showed a day-to-night change in the firing frequency of DMH cells, with higher activity during the dark phase. This was abolished by HFD consumption, resulting in a decreased threshold for action potential generation during the day and therefore increased electrical activity at this phase. We propose this electrophysiological disturbance as a mechanism for the induction of abnormal daytime feeding, previously observed for HFD-fed animals, which might in turn contribute to the development of obesity. In addition, we provide an electrophysiological characteristic of DMH neurons with a separation into three anatomically and functionally distinct subpopulations, namely, the compact part, separating the structure into the ventral and dorsal divisions. Our study is the first to show electrophysiological complexity of the DMH with its sensitivity to diet and daily rhythms.
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Affiliation(s)
- Anna Magdalena Sanetra
- Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Krakow, Poland
| | - Katarzyna Palus-Chramiec
- Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Krakow, Poland
| | - Lukasz Chrobok
- Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Krakow, Poland.,School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK
| | - Marian Henryk Lewandowski
- Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Krakow, Poland
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4
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Roger C, Lasbleiz A, Guye M, Dutour A, Gaborit B, Ranjeva JP. The Role of the Human Hypothalamus in Food Intake Networks: An MRI Perspective. Front Nutr 2022; 8:760914. [PMID: 35047539 PMCID: PMC8762294 DOI: 10.3389/fnut.2021.760914] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 12/07/2021] [Indexed: 12/12/2022] Open
Abstract
Hypothalamus (HT), this small structure often perceived through the prism of neuroimaging as morphologically and functionally homogeneous, plays a key role in the primitive act of feeding. The current paper aims at reviewing the contribution of magnetic resonance imaging (MRI) in the study of the role of the HT in food intake regulation. It focuses on the different MRI techniques that have been used to describe structurally and functionally the Human HT. The latest advances in HT parcellation as well as perspectives in this field are presented. The value of MRI in the study of eating disorders such as anorexia nervosa (AN) and obesity are also highlighted.
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Affiliation(s)
- Coleen Roger
- Centre de Résonance Magnétique Biologique et Médicale (CRMBM), Centre National de la Recherche Scientifique (CNRS), Université Aix-Marseille, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (CEMEREM), Assistance Publique-Hôpitaux de Marseille (AP-HM), Hôpital Universitaire de la Timone, Marseille, France
| | - Adèle Lasbleiz
- Centre d'Exploration Métabolique par Résonance Magnétique (CEMEREM), Assistance Publique-Hôpitaux de Marseille (AP-HM), Hôpital Universitaire de la Timone, Marseille, France.,Département d'Endocrinologie, Assistance Publique-Hôpitaux de Marseille (AP-HM), Hôpital de la Conception, Marseille, France
| | - Maxime Guye
- Centre de Résonance Magnétique Biologique et Médicale (CRMBM), Centre National de la Recherche Scientifique (CNRS), Université Aix-Marseille, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (CEMEREM), Assistance Publique-Hôpitaux de Marseille (AP-HM), Hôpital Universitaire de la Timone, Marseille, France
| | - Anne Dutour
- Département d'Endocrinologie, Assistance Publique-Hôpitaux de Marseille (AP-HM), Hôpital de la Conception, Marseille, France
| | - Bénédicte Gaborit
- Département d'Endocrinologie, Assistance Publique-Hôpitaux de Marseille (AP-HM), Hôpital de la Conception, Marseille, France
| | - Jean-Philippe Ranjeva
- Centre de Résonance Magnétique Biologique et Médicale (CRMBM), Centre National de la Recherche Scientifique (CNRS), Université Aix-Marseille, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (CEMEREM), Assistance Publique-Hôpitaux de Marseille (AP-HM), Hôpital Universitaire de la Timone, Marseille, France
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5
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Li ZF, Chometton S, Guèvremont G, Timofeeva E, Timofeev I. Compulsive Eating in a Rat Model of Binge Eating Disorder Under Conditioned Fear and Exploration of Neural Mechanisms With c-fos mRNA Expression. Front Neurosci 2021; 15:777572. [PMID: 34912190 PMCID: PMC8666959 DOI: 10.3389/fnins.2021.777572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 11/04/2021] [Indexed: 11/13/2022] Open
Abstract
Compulsive eating is the most obstinate feature of binge eating disorder. In this study, we observed the compulsive eating in our stress-induced binge-like eating rat model using a conflicting test, where sucrose and an aversively conditioned stimulus were presented at the same time. In this conflicting situation, the binge-like eating prone rats (BEPs), compared to the binge-like eating resistant rats (BERs), showed persistent high sucrose intake and inhibited fear response, respectively, indicating a deficit in palatability devaluation and stronger anxiolytic response to sucrose in the BEPs. We further analyzed the neuronal activation with c-fos mRNA in situ hybridization. Surprisingly, the sucrose access under conditioned fear did not inhibit the activity of amygdala; instead, it activated the central amygdala. In the BEPs, sucrose reduced the response of the paraventricular hypothalamic nucleus (PVN), while enhancing activities in the lateral hypothalamic area (LHA) to the CS. The resistance to devaluating the palatable food in the BEPs could be a result of persistent Acb response to sucrose intake and attenuated recruitment of the medial prefrontal cortex (mPFC). We interpret this finding as that the reward system of the BEPs overcame the homeostasis system and the stress-responding system.
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Affiliation(s)
- Zhi Fei Li
- The First Affiliated Hospital, Jinan University, Guangzhou, China.,Faculté de Médecine, Département de Médecine Moléculaire, Université Laval, Quebec City, QC, Canada.,Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, QC, Canada.,Centre de Recherche CERVO, Quebec City, QC, Canada
| | - Sandrine Chometton
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, QC, Canada
| | - Geneviève Guèvremont
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, QC, Canada
| | - Elena Timofeeva
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, QC, Canada
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6
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Caba M, Meza E, Escobar C, Jiménez A, Caba-Flores MD, Moreno-Cortés ML, Melo AI. Oxytocinergic cells of the posterior hypothalamic paraventricular nucleus participate in the food entrained clock. Sci Rep 2021; 11:19957. [PMID: 34620909 PMCID: PMC8497610 DOI: 10.1038/s41598-021-99266-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 09/22/2021] [Indexed: 12/17/2022] Open
Abstract
The mechanisms underlying food anticipatory activity are still poorly understood. Here we explored the role of oxytocin (OT) and the protein c-Fos in the supraoptic nucleus (SON), medial (PVNm) and posterior (PVNp) regions of the paraventricular hypothalamic nucleus. Adult rats were assigned to one of four groups: scheduled restricted feeding (RF), ad libitum (AL), fasting after restricted feeding (RF-F), to explore the possible persistence of oscillations, or ad libitum fasted (AL-F). In the SON and in the PVNm, OT cells were c-Fos positive after food intake; in contrast, OT cells in the PVNp showed c-Fos activation in anticipation to food access, which persisted in RF-F subjects. We conclude that OT and non-OT cells of the SON and PVNm may play a role as recipients of the entraining signal provided by food intake, whereas those of the PVNp which contain motor preautonomic cells that project to peripheral organs, may be involved in the hormonal and metabolic anticipatory changes in preparation for food presentation and thus, may be part of a link between central and peripheral oscillators. In addition, due to their persistent activation they may participate in the neuronal network for the clock mechanism that leads to food entrainment.
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Affiliation(s)
- Mario Caba
- Centro de Investigaciones Biomédicas, Universidad Veracruzana, Xalapa, Ver., Mexico.
| | - Enrique Meza
- Centro de Investigaciones Biomédicas, Universidad Veracruzana, Xalapa, Ver., Mexico
| | - Carolina Escobar
- Facultad de Medicina, Universidad Nacional Autónoma de México, CDMX, Mexico
| | - Angeles Jiménez
- Centro de Investigación en Reproducción Animal, CINVESTAV-UAT, Tlaxcala, Tlax, Mexico
| | | | | | - Angel I Melo
- Centro de Investigación en Reproducción Animal, CINVESTAV-UAT, Tlaxcala, Tlax, Mexico
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7
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Bertile F, Plumel M, Maes P, Hirschler A, Challet E. Daytime Restricted Feeding Affects Day-Night Variations in Mouse Cerebellar Proteome. Front Mol Neurosci 2021; 14:613161. [PMID: 33912010 PMCID: PMC8072461 DOI: 10.3389/fnmol.2021.613161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 03/12/2021] [Indexed: 12/14/2022] Open
Abstract
The cerebellum harbors a circadian clock that can be shifted by scheduled mealtime and participates in behavioral anticipation of food access. Large-scale two-dimensional difference gel electrophoresis (2D-DIGE) combined with mass spectrometry was used to identify day–night variations in the cerebellar proteome of mice fed either during daytime or nighttime. Experimental conditions led to modified expression of 89 cerebellar proteins contained in 63 protein spots. Five and 33 spots were changed respectively by time-of-day or feeding conditions. Strikingly, several proteins of the heat-shock protein family (i.e., Hsp90aa1, 90ab1, 90b1, and Hspa2, 4, 5, 8, 9) were down-regulated in the cerebellum of daytime food-restricted mice. This was also the case for brain fatty acid protein (Fabp7) and enzymes involved in oxidative phosphorylation (Ndufs1) or folate metabolism (Aldh1l1). In contrast, aldolase C (Aldoc or zebrin II) and pyruvate carboxylase (Pc), two enzymes involved in carbohydrate metabolism, and vesicle-fusing ATPase (Nsf) were up-regulated during daytime restricted feeding, possibly reflecting increased neuronal activity. Significant feeding × time-of-day interactions were found for changes in the intensity of 20 spots. Guanine nucleotide-binding protein G(o) subunit alpha (Gnao1) was more expressed in the cerebellum before food access. Neuronal calcium-sensor proteins [i.e., parvalbumin (Pvalb) and visinin-like protein 1 (Vsnl1)] were inversely regulated in daytime food-restricted mice, compared to control mice fed at night. Furthermore, expression of three enzymes modulating the circadian clockwork, namely heterogeneous nuclear ribonucleoprotein K (Hnrnpk), serine/threonine-protein phosphatases 1 (Ppp1cc and Ppp1cb subunits) and 5 (Ppp5), was differentially altered by daytime restricted feeding. Besides cerebellar proteins affected only by feeding conditions or daily cues, specific changes in in protein abundance before food access may be related to behavioral anticipation of food access and/or feeding-induced shift of the cerebellar clockwork.
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Affiliation(s)
- Fabrice Bertile
- Institut Pluridisciplinaire Hubert Curien, LSMBO, Université de Strasbourg, Centre National de la Recherche Scientifique, Strasbourg, France
| | - Marine Plumel
- Institut Pluridisciplinaire Hubert Curien, LSMBO, Université de Strasbourg, Centre National de la Recherche Scientifique, Strasbourg, France
| | - Pauline Maes
- Institut Pluridisciplinaire Hubert Curien, LSMBO, Université de Strasbourg, Centre National de la Recherche Scientifique, Strasbourg, France
| | - Aurélie Hirschler
- Institut Pluridisciplinaire Hubert Curien, LSMBO, Université de Strasbourg, Centre National de la Recherche Scientifique, Strasbourg, France
| | - Etienne Challet
- Institut des Neurosciences Cellulaires et Intégratives, Université de Strasbourg, Centre National de la Recherche Scientifique, Strasbourg, France
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Kamali A, Karbasian N, Ghazi Sherbaf F, Wilken LA, Aein A, Sair HI, Arevalo Espejo O, Rabiei P, Choi SJ, Mirbagheri S, Riascos RF, Hasan KM. Uncovering the Dorsal Thalamo-hypothalamic Tract of the Human Limbic System. Neuroscience 2020; 432:55-62. [DOI: 10.1016/j.neuroscience.2020.02.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 02/14/2020] [Accepted: 02/17/2020] [Indexed: 10/24/2022]
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9
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Caba M, Huerta C, Meza E, Hernández M, Rovirosa-Hernández MJ. Oxytocinergic Cells of the Hypothalamic Paraventricular Nucleus Are Involved in Food Entrainment. Front Neurosci 2020; 14:49. [PMID: 32082116 PMCID: PMC7005215 DOI: 10.3389/fnins.2020.00049] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 01/13/2020] [Indexed: 12/22/2022] Open
Abstract
When food is presented at a specific time of day subjects develop intense locomotor behavior before food presentation, termed food anticipatory activity (FAA). Metabolic and hormonal parameters, as well as neural structures also shift their rhythm according to mealtime. Food-entrained activity rhythms are thought to be driven by a distributed system of central and peripheral oscillators sensitive to food cues, but it is not well understood how they are organized for the expression of FAA. The hormone Oxytocin plays an important role in food intake, satiety and homeostatic glucose metabolism and although it is recognized that food is the main cue for food entrainment this hormone has not been implicated in FAA. Here we investigated the activity of oxytocinergic (OTergic) cells of the hypothalamus in relation to the timing of feeding in rabbit pups, a natural model of food entrainment. We found that OTergic cells of the supraoptic nucleus and the main body of the paraventricular nucleus (PVN) are activated after feeding which suggests that OT may be an entraining signal for food synchronization. Moreover, a detailed analysis of the PVN revealed that OTergic cells of the caudal PVN and a subpopulation in the dorsal part of the main body of this nucleus shows activation before the time of food but not 12 h later. Moreover this pattern persists in fasted subjects at the time of the previous scheduled time of nursing. The fact that those OTergic cells of the dorsal and caudal part of the PVN contain preautonomic cells that project to the adrenal, pancreas and liver perhaps may be related to the physiological changes in preparation for food ingestion, and synchronization of peripheral oscillators, which remains to be determined; perhaps they play a main role in the central oscillatory mechanism of FAA as their activity persists in fasted subjects at the time of the next feeding time.
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Affiliation(s)
- Mario Caba
- Centro de Investigaciones Biomédicas, Universidad Veracruzana, Xalapa, Mexico
| | - César Huerta
- Doctorado en Ciencias Biomédicas, Centro de Investigaciones Biomédicas, Universidad Veracruzana, Xalapa, Mexico
| | - Enrique Meza
- Centro de Investigaciones Biomédicas, Universidad Veracruzana, Xalapa, Mexico
| | - Manuel Hernández
- Doctorado en Ciencias Biomédicas, Centro de Investigaciones Biomédicas, Universidad Veracruzana, Xalapa, Mexico
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11
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Neural substrates of fear-induced hypophagia in male and female rats. Brain Struct Funct 2018; 223:2925-2947. [PMID: 29704225 DOI: 10.1007/s00429-018-1668-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Accepted: 04/19/2018] [Indexed: 12/18/2022]
Abstract
Cessation of eating under fear is an adaptive response that aids survival by prioritizing the expression of defensive behaviors over feeding behavior. However, this response can become maladaptive when persistent. Thus, accurate mediation of the competition between fear and feeding is important in health and disease; yet, the underlying neural substrates are largely unknown. The current study identified brain regions that were recruited when a fear cue inhibited feeding in male and female rats. We used a previously established behavioral paradigm to elicit hypophagia with a conditioned cue for footshocks, and Fos imaging to map activation patterns during this behavior. We found that distinct patterns of recruitment were associated with feeding and fear expression, and that these patterns were similar in males and females except within the medial prefrontal cortex (mPFC). In both sexes, food consumption was associated with activation of cell groups in the central amygdalar nucleus, hypothalamus, and dorsal vagal complex, and exposure to food cues was associated with activation of the anterior basolateral amygdalar nucleus. In contrast, fear expression was associated with activation of the lateral and posterior basomedial amygdalar nuclei. Interestingly, selective recruitment of the mPFC in females, but not in males, was associated with both feeding and freezing behavior, suggesting sex differences in the neuronal processing underlying the competition between feeding and fear. This study provided the first evidence of the neural network mediating fear-induced hypophagia, and important functional activation maps for future interrogation of the underlying neural substrates.
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12
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Brain Activity during Methamphetamine Anticipation in a Non-Invasive Self-Administration Paradigm in Mice. eNeuro 2018; 5:eN-NWR-0433-17. [PMID: 29632871 PMCID: PMC5889482 DOI: 10.1523/eneuro.0433-17.2018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 02/14/2018] [Accepted: 02/21/2018] [Indexed: 12/13/2022] Open
Abstract
The ability to sense time and anticipate events is critical for survival. Learned responses that allow anticipation of the availability of food or water have been intensively studied. While anticipatory behaviors also occur prior to availability of regularly available rewards, there has been relatively little work on anticipation of drugs of abuse, specifically methamphetamine (MA). In the present study, we used a protocol that avoided possible CNS effects of stresses of handling or surgery by testing anticipation of MA availability in animals living in their home cages, with daily voluntary access to the drug at a fixed time of day. Anticipation was operationalized as the amount of wheel running prior to MA availability. Mice were divided into four groups given access to either nebulized MA or water, in early or late day. Animals with access to MA, but not water controls, showed anticipatory activity, with more anticipation in early compared to late day and significant interaction effects. Next, we explored the neural basis of the MA anticipation, using c-FOS expression, in animals euthanized at the usual time of nebulization access. In the dorsomedial hypothalamus (DMH) and orbitofrontal cortex (OFC), the pattern of c-FOS expression paralleled that of anticipatory behavior, with significant main and interaction effects of treatment and time of day. The results for the lateral septum (LS) were significant for main effects and marginally significant for interaction effects. These studies suggest that anticipation of MA is associated with activation of brain regions important in circadian timing, emotional regulation, and decision making.
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13
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Neural Mechanisms of Circadian Regulation of Natural and Drug Reward. Neural Plast 2017; 2017:5720842. [PMID: 29359051 PMCID: PMC5735684 DOI: 10.1155/2017/5720842] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 09/07/2017] [Accepted: 10/11/2017] [Indexed: 01/26/2023] Open
Abstract
Circadian rhythms are endogenously generated near 24-hour variations of physiological and behavioral functions. In humans, disruptions to the circadian system are associated with negative health outcomes, including metabolic, immune, and psychiatric diseases, such as addiction. Animal models suggest bidirectional relationships between the circadian system and drugs of abuse, whereby desynchrony, misalignment, or disruption may promote vulnerability to drug use and the transition to addiction, while exposure to drugs of abuse may entrain, disrupt, or perturb the circadian timing system. Recent evidence suggests natural (i.e., food) and drug rewards may influence overlapping neural circuitry, and the circadian system may modulate the physiological and behavioral responses to these stimuli. Environmental disruptions, such as shifting schedules or shorter/longer days, influence food and drug intake, and certain mutations of circadian genes that control cellular rhythms are associated with altered behavioral reward. We highlight the more recent findings associating circadian rhythms to reward function, linking environmental and genetic evidence to natural and drug reward and related neural circuitry.
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14
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Scheduled feeding restores memory and modulates c-Fos expression in the suprachiasmatic nucleus and septohippocampal complex. Sci Rep 2017; 7:6755. [PMID: 28754901 PMCID: PMC5533780 DOI: 10.1038/s41598-017-06963-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 06/22/2017] [Indexed: 11/09/2022] Open
Abstract
Disruptions in circadian timing impair spatial memory in humans and rodents. Circadian-arrhythmic Siberian hamsters (Phodopus sungorus) exhibit substantial deficits in spatial working memory as assessed by a spontaneous alternation (SA) task. The present study found that daily scheduled feeding rescued spatial memory deficits in these arrhythmic animals. Improvements in memory persisted for at least 3 weeks after the arrhythmic hamsters were switched back to ad libitum feeding. During ad libitum feeding, locomotor activity resumed its arrhythmic state, but performance on the SA task varied across the day with a peak in daily performance that corresponded to the previous daily window of food anticipation. At the end of scheduled feeding, c-Fos brain mapping revealed differential gene expression in entrained versus arrhythmic hamsters in the suprachiasmatic nucleus (SCN) that paralleled changes in the medial septum and hippocampus, but not in other neural structures. These data show that scheduled feeding can improve cognitive performance when SCN timing has been compromised, possibly by coordinating activity in the SCN and septohippocampal pathway.
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15
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Millan EZ, Ong Z, McNally GP. Paraventricular thalamus: Gateway to feeding, appetitive motivation, and drug addiction. PROGRESS IN BRAIN RESEARCH 2017; 235:113-137. [DOI: 10.1016/bs.pbr.2017.07.006] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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16
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Stress differentially regulates brain expression of corticotropin-releasing factor in binge-like eating prone and resistant female rats. Appetite 2016; 107:585-595. [DOI: 10.1016/j.appet.2016.09.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 09/06/2016] [Accepted: 09/07/2016] [Indexed: 12/26/2022]
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17
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Hsu TM, Suarez AN, Kanoski SE. Ghrelin: A link between memory and ingestive behavior. Physiol Behav 2016; 162:10-7. [PMID: 27072509 DOI: 10.1016/j.physbeh.2016.03.039] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 03/29/2016] [Accepted: 03/31/2016] [Indexed: 01/25/2023]
Abstract
Feeding is a highly complex behavior that is influenced by learned associations between external and internal cues. The type of excessive feeding behavior contributing to obesity onset and metabolic deficit may be based, in part, on conditioned appetitive and ingestive behaviors that occur in response to environmental and/or interoceptive cues associated with palatable food. Therefore, there is a critical need to understand the neurobiology underlying learned aspects of feeding behavior. The stomach-derived "hunger" hormone, ghrelin, stimulates appetite and food intake and may function as an important biological substrate linking mnemonic processes with feeding control. The current review highlights data supporting a role for ghrelin in mediating the cognitive and neurobiological mechanisms that underlie conditioned feeding behavior. We discuss the role of learning and memory on food intake control (with a particular focus on hippocampal-dependent memory processes) and provide an overview of conditioned cephalic endocrine responses. A neurobiological framework is provided through which conditioned cephalic ghrelin secretion signals in neurons in the hippocampus, which then engage orexigenic neural circuitry in the lateral hypothalamus to express learned feeding behavior.
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Affiliation(s)
- Ted M Hsu
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA; Neuroscience Program, University of Southern California, Los Angeles, CA, USA
| | - Andrea N Suarez
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Scott E Kanoski
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA; Neuroscience Program, University of Southern California, Los Angeles, CA, USA.
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18
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Abstract
Advances in neuro-technology for mapping, manipulating, and monitoring molecularly defined cell types are rapidly advancing insight into neural circuits that regulate appetite. Here, we review these important tools and their applications in circuits that control food seeking and consumption. Technical capabilities provided by these tools establish a rigorous experimental framework for research into the neurobiology of hunger.
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Affiliation(s)
- Scott M Sternson
- Janelia Research Campus, HHMI, 19700 Helix Drive, Ashburn, VA 20147, USA.
| | - Deniz Atasoy
- Department of Physiology, School of Medicine, Istanbul Medipol University, 34810 Istanbul, Turkey
| | - J Nicholas Betley
- Janelia Research Campus, HHMI, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Fredrick E Henry
- Janelia Research Campus, HHMI, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Shengjin Xu
- Janelia Research Campus, HHMI, 19700 Helix Drive, Ashburn, VA 20147, USA
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19
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Namvar S, Gyte A, Denn M, Leighton B, Piggins HD. Dietary fat and corticosterone levels are contributing factors to meal anticipation. Am J Physiol Regul Integr Comp Physiol 2016; 310:R711-23. [PMID: 26818054 PMCID: PMC4867411 DOI: 10.1152/ajpregu.00308.2015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 01/22/2016] [Indexed: 11/22/2022]
Abstract
Daily restricted access to food leads to the development of food anticipatory activity and metabolism, which depends upon an as yet unidentified food-entrainable oscillator(s). A premeal anticipatory peak in circulating hormones, including corticosterone is also elicited by daily restricted feeding. High-fat feeding is associated with elevated levels of corticosterone with disrupted circadian rhythms and a failure to develop robust meal anticipation. It is not clear whether the disrupted corticosterone rhythm, resulting from high-fat feeding contributes to attenuated meal anticipation in high-fat fed rats. Our aim was to better characterize meal anticipation in rats fed a low- or high-fat diet, and to better understand the role of corticosterone in this process. To this end, we utilized behavioral observations, hypothalamic c-Fos expression, and indirect calorimetry to assess meal entrainment. We also used the glucocorticoid receptor antagonist, RU486, to dissect out the role of corticosterone in meal anticipation in rats given daily access to a meal with different fat content. Restricted access to a low-fat diet led to robust meal anticipation, as well as entrainment of hypothalamic c-Fos expression, metabolism, and circulating corticosterone. These measures were significantly attenuated in response to a high-fat diet, and animals on this diet exhibited a postanticipatory rise in corticosterone. Interestingly, antagonism of glucocorticoid activity using RU486 attenuated meal anticipation in low-fat fed rats, but promoted meal anticipation in high-fat-fed rats. These findings suggest an important role for corticosterone in the regulation of meal anticipation in a manner dependent upon dietary fat content.
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Affiliation(s)
- Sara Namvar
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom; and
| | - Amy Gyte
- AstraZeneca Research and Development, Mereside, Alderley Park, Macclesfield, United Kingdom
| | - Mark Denn
- AstraZeneca Research and Development, Mereside, Alderley Park, Macclesfield, United Kingdom
| | - Brendan Leighton
- AstraZeneca Research and Development, Mereside, Alderley Park, Macclesfield, United Kingdom
| | - Hugh D Piggins
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom; and
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20
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Dietze S, Lees KR, Fink H, Brosda J, Voigt JP. Food Deprivation, Body Weight Loss and Anxiety-Related Behavior in Rats. Animals (Basel) 2016; 6:ani6010004. [PMID: 26751481 PMCID: PMC4730121 DOI: 10.3390/ani6010004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 12/17/2015] [Accepted: 12/18/2015] [Indexed: 11/27/2022] Open
Abstract
Simple Summary Food deprivation protocols are frequently used in behavioral studies. However, there is limited evidence as to when food deprivation compromises animal welfare. Regarding the refinement of experiments involving animals, this study investigated the effects of food deprivation on body weight loss and behavior in male and female rats. Sex difference in behavior and motivational state after food deprivation is the main finding of the study. The data highlights the need for tailored pilot experiments to evaluate the impact of food deprivation on animals with regard to the 3Rs principles (replacement, reduction, refinement) in animal science. Abstract In behavioral studies, food deprivation protocols are routinely used to initiate or maintain motivational states that are required in a particular test situation. However, there is limited evidence as to when food deprivation compromises animal welfare. This study investigated the effects of different lengths of food deprivation periods and restricted (fixed-time) feeding on body weight loss as well as anxiety-related and motivated behavior in 5–6 month old male and female Wistar rats. The observed body weight loss was not influenced by sex and ranged between 4% (16 h deprivation) to approximately 9% (fixed-time feeding). Despite significant body weight loss in all groups, the motivation to eat under the aversive test conditions of the modified open field test increased only after 48 h of food deprivation. Long-lasting effects on anxiety as measured in the elevated plus maze test 24 h after refeeding have not been observed, although fixed-time feeding could possibly lead to a lasting anxiogenic effect in female rats. Overall, female rats showed a more anxiolytic profile in both tests when compared to male rats. Despite these sex differences, results suggest that food deprivation is not always paralleled by an increased motivation to feed in a conflict situation. This is an important finding as it highlights the need for tailored pilot experiments to evaluate the impact of food deprivation protocols on animals in regard to the principles of the 3Rs introduced by Russell and Burch.
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Affiliation(s)
- Silke Dietze
- Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Koserstr. 20, Berlin 14195, Germany.
| | - Katarina R Lees
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK.
| | - Heidrun Fink
- Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Koserstr. 20, Berlin 14195, Germany.
| | - Jan Brosda
- Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Koserstr. 20, Berlin 14195, Germany.
| | - Jörg-Peter Voigt
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK.
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21
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Hsu TM, Hahn JD, Konanur VR, Noble EE, Suarez AN, Thai J, Nakamoto EM, Kanoski SE. Hippocampus ghrelin signaling mediates appetite through lateral hypothalamic orexin pathways. eLife 2015; 4. [PMID: 26745307 PMCID: PMC4695382 DOI: 10.7554/elife.11190] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 11/06/2015] [Indexed: 12/14/2022] Open
Abstract
Feeding behavior rarely occurs in direct response to metabolic deficit, yet the overwhelming majority of research on the biology of food intake control has focused on basic metabolic and homeostatic neurobiological substrates. Most animals, including humans, have habitual feeding patterns in which meals are consumed based on learned and/or environmental factors. Here we illuminate a novel neural system regulating higher-order aspects of feeding through which the gut-derived hormone ghrelin communicates with ventral hippocampus (vHP) neurons to stimulate meal-entrained conditioned appetite. Additional results show that the lateral hypothalamus (LHA) is a critical downstream substrate for vHP ghrelin-mediated hyperphagia and that vHP ghrelin activated neurons communicate directly with neurons in the LHA that express the neuropeptide, orexin. Furthermore, activation of downstream orexin-1 receptors is required for vHP ghrelin-mediated hyperphagia. These findings reveal novel neurobiological circuitry regulating appetite through which ghrelin signaling in hippocampal neurons engages LHA orexin signaling.
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Affiliation(s)
- Ted M Hsu
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States.,Neuroscience Program, University of Southern California, Los Angeles, United States
| | - Joel D Hahn
- Neurobiology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States
| | - Vaibhav R Konanur
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States
| | - Emily E Noble
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States
| | - Andrea N Suarez
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States
| | - Jessica Thai
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States
| | - Emily M Nakamoto
- Neuroscience Program, University of Southern California, Los Angeles, United States
| | - Scott E Kanoski
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States.,Neuroscience Program, University of Southern California, Los Angeles, United States
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22
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Kalló I, Molnár CS, Szöke S, Fekete C, Hrabovszky E, Liposits Z. Area-specific analysis of the distribution of hypothalamic neurons projecting to the rat ventral tegmental area, with special reference to the GABAergic and glutamatergic efferents. Front Neuroanat 2015; 9:112. [PMID: 26388742 PMCID: PMC4559648 DOI: 10.3389/fnana.2015.00112] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 07/30/2015] [Indexed: 12/22/2022] Open
Abstract
The ventral tegmental area (VTA) is a main regulator of reward and integrates a wide scale of hormonal and neuronal information. Feeding-, energy expenditure-, stress, adaptation- and reproduction-related hypothalamic signals are processed in the VTA and influence the reward processes. However, the neuroanatomical origin and chemical phenotype of neurons mediating these signals to the VTA have not been fully characterized. In this study we have systematically mapped hypothalamic neurons that project to the VTA using the retrograde tracer Choleratoxin B subunit (CTB) and analyzed their putative gamma-aminobutyric acid (GABA) and/or glutamate character with in situ hybridization in male rats. 23.93 ± 3.91% of hypothalamic neurons projecting to the VTA was found in preoptic and 76.27 ± 4.88% in anterior, tuberal and mammillary hypothalamic regions. Nearly half of the retrogradely-labeled neurons in the preoptic, and more than one third in the anterior, tuberal and mammillary hypothalamus appeared in medially located regions. The analyses of vesicular glutamate transporter 2 (VGLUT2) and glutamate decarboxylase 65 (GAD65) mRNA expression revealed both amino acid markers in different subsets of retrogradely-labeled hypothalamic neurons, typically with the predominance of the glutamatergic marker VGLUT2. About one tenth of CTB-IR neurons were GAD65-positive even in hypothalamic nuclei expressing primarily VGLUT2. Some regions were populated mostly by GAD65 mRNA-containing retrogradely-labeled neurons. These included the perifornical part of the lateral hypothalamus where 58.63 ± 19.04% of CTB-IR neurons were GABAergic. These results indicate that both the medial and lateral nuclear compartments of the hypothalamus provide substantial input to the VTA. Furthermore, colocalization studies revealed that these projections not only use glutamate but also GABA for neurotransmission. These GABAergic afferents may underlie important inhibitory mechanism to fine-tune the reward value of specific signals in the VTA.
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Affiliation(s)
- Imre Kalló
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences Budapest, Hungary ; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University Budapest, Hungary
| | - Csilla S Molnár
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences Budapest, Hungary
| | - Sarolta Szöke
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences Budapest, Hungary
| | - Csaba Fekete
- Laboratory of Integrative Neuroendocrinology, Institute of Experimental Medicine, Hungarian Academy of Sciences Budapest, Hungary ; Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Tupper Research Institute, Tufts Medical Center Boston, MA, USA
| | - Erik Hrabovszky
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences Budapest, Hungary
| | - Zsolt Liposits
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences Budapest, Hungary ; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University Budapest, Hungary
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23
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Calvez J, Lenglos C, de Ávila C, Guèvremont G, Timofeeva E. Differential effects of central administration of relaxin-3 on food intake and hypothalamic neuropeptides in male and female rats. GENES BRAIN AND BEHAVIOR 2015; 14:550-63. [DOI: 10.1111/gbb.12236] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 07/25/2015] [Accepted: 07/26/2015] [Indexed: 12/22/2022]
Affiliation(s)
- J. Calvez
- Faculté de Médecine, Département de Psychiatrie et de Neurosciences, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec; Université Laval; Québec (QC) Canada
| | - C. Lenglos
- Faculté de Médecine, Département de Psychiatrie et de Neurosciences, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec; Université Laval; Québec (QC) Canada
| | - C. de Ávila
- Faculté de Médecine, Département de Psychiatrie et de Neurosciences, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec; Université Laval; Québec (QC) Canada
| | - G. Guèvremont
- Faculté de Médecine, Département de Psychiatrie et de Neurosciences, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec; Université Laval; Québec (QC) Canada
| | - E. Timofeeva
- Faculté de Médecine, Département de Psychiatrie et de Neurosciences, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec; Université Laval; Québec (QC) Canada
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24
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Dantas-Ferreira RF, Dumont S, Gourmelen S, Cipolla-Neto J, Simonneaux V, Pévet P, Challet E. Food-anticipatory activity in Syrian hamsters: behavioral and molecular responses in the hypothalamus according to photoperiodic conditions. PLoS One 2015; 10:e0126519. [PMID: 25970608 PMCID: PMC4430487 DOI: 10.1371/journal.pone.0126519] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 04/03/2015] [Indexed: 11/18/2022] Open
Abstract
When food availability is restricted, animals adjust their behavior according to the timing of food access. Most rodents, such as rats and mice, and a wide number of other animals express before timed food access a bout of activity, defined as food-anticipatory activity (FAA). One notable exception amongst rodents is the Syrian hamster, a photoperiodic species that is not prone to express FAA. The present study was designed to understand the reasons for the low FAA in that species. First, we used both wheel-running activity and general cage activity to assess locomotor behavior. Second, the possible effects of photoperiod was tested by challenging hamsters with restricted feeding under long (LP) or short (SP) photoperiods. Third, because daytime light may inhibit voluntary activity, hamsters were also exposed to successive steps of full and skeleton photoperiods (two 1-h light pulses simulating dawn and dusk). When hamsters were exposed to skeleton photoperiods, not full photoperiod, they expressed FAA in the wheel independently of daylength, indicating that FAA in the wheel is masked by daytime light under full photoperiods. During FAA under skeleton photoperiods, c-Fos expression was increased in the arcuate nuclei independently of the photoperiod, but differentially increased in the ventromedial and dorsomedial hypothalamic nuclei according to the photoperiod. FAA in general activity was hardly modulated by daytime light, but was reduced under SP. Together, these findings show that food-restricted Syrian hamsters are not prone to display FAA under common laboratory conditions, because of the presence of light during daytime that suppresses FAA expression in the wheel.
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Affiliation(s)
- Rosana F. Dantas-Ferreira
- Department of Neurobiology of Rhythms, Institute of Cellular and Integrative Neurosciences, UPR 3212 CNRS, University of Strasbourg, Strasbourg, France
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Stéphanie Dumont
- Department of Neurobiology of Rhythms, Institute of Cellular and Integrative Neurosciences, UPR 3212 CNRS, University of Strasbourg, Strasbourg, France
| | - Sylviane Gourmelen
- Department of Neurobiology of Rhythms, Institute of Cellular and Integrative Neurosciences, UPR 3212 CNRS, University of Strasbourg, Strasbourg, France
| | - José Cipolla-Neto
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Valérie Simonneaux
- Department of Neurobiology of Rhythms, Institute of Cellular and Integrative Neurosciences, UPR 3212 CNRS, University of Strasbourg, Strasbourg, France
| | - Paul Pévet
- Department of Neurobiology of Rhythms, Institute of Cellular and Integrative Neurosciences, UPR 3212 CNRS, University of Strasbourg, Strasbourg, France
| | - Etienne Challet
- Department of Neurobiology of Rhythms, Institute of Cellular and Integrative Neurosciences, UPR 3212 CNRS, University of Strasbourg, Strasbourg, France
- * E-mail:
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25
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Li Z, Wang Y, Sun KK, Wang K, Sun ZS, Zhao M, Wang J. Sex-related difference in food-anticipatory activity of mice. Horm Behav 2015; 70:38-46. [PMID: 25736535 DOI: 10.1016/j.yhbeh.2015.02.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 02/13/2015] [Accepted: 02/18/2015] [Indexed: 12/30/2022]
Abstract
The expression of food-anticipatory activity (FAA) is induced by restricted feeding (RF), and its entrainment requires food-entrainable oscillators, the neuroanatomical basis of which is currently unclear. Although RF impacts various hormones, sex-related differences in FAA are unclear. 'Here, we report significantly more food-anticipatory wheel-running activity in male than in female mice during RF. In parallel with the sex-related difference in FAA, male and female mice display different food intake and body weight in response to RF. Since gonadal hormones could be involved in the sex-specific difference in FAA, we compared sham and gonadectomized male and female wild-type mice. In gonadectomized mice, the sex difference in FAA was abolished, indicating a role for gonadal hormones in FAA. Further, plasma concentrations of the hormone ghrelin were higher in female than in male mice during ad libitum (AL) feeding, and RF induced a temporal advance in its peak in both sexes. RF also shifted the expression peak of the circadian gene mPer1 in the hippocampus and liver, although no sex difference was found in either the level or the cyclic phase of its expression. Per1(Brdm1) mutant mice were still sexually dimorphic for FAA, but diminished FAA was noted in both male and female Per2(Brdm1) mutant mice. In summary, our results imply that gonadal hormones contribute to the sex difference in FAA, possibly through modulating ghrelin activity.
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Affiliation(s)
- Zhigang Li
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Medicine, Shanxi Agricultural University, Taigu 030801, China; Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China
| | - Yan Wang
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China
| | | | - Kangli Wang
- Institute of Genomic Medicine, Wenzhou Medical College, Wenzhou 325000, China
| | - Zhong Sheng Sun
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China; Institute of Genomic Medicine, Wenzhou Medical College, Wenzhou 325000, China.
| | - Mei Zhao
- Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China.
| | - Jundong Wang
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Medicine, Shanxi Agricultural University, Taigu 030801, China.
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26
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Munn RGK, Tyree SM, McNaughton N, Bilkey DK. The frequency of hippocampal theta rhythm is modulated on a circadian period and is entrained by food availability. Front Behav Neurosci 2015; 9:61. [PMID: 25814943 PMCID: PMC4356069 DOI: 10.3389/fnbeh.2015.00061] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 02/23/2015] [Indexed: 11/13/2022] Open
Abstract
The hippocampal formation plays a critical role in the generation of episodic memory. While the encoding of the spatial and contextual components of memory have been extensively studied, how the hippocampus encodes temporal information, especially at long time intervals, is less well understood. The activity of place cells in hippocampus has previously been shown to be modulated at a circadian time-scale, entrained by a behavioral stimulus, but not entrained by light. The experimental procedures used in the previous study of this phenomenon, however, necessarily conflated two alternative entraining stimuli, the exposure to the recording environment and the availability of food, making it impossible to distinguish between these possibilities. Here we demonstrate that the frequency of theta-band hippocampal EEG varies with a circadian period in freely moving animals and that this periodicity mirrors changes in the firing rate of hippocampal neurons. Theta activity serves, therefore, as a proxy of circadian-modulated hippocampal neuronal activity. We then demonstrate that the frequency of hippocampal theta driven by stimulation of the reticular formation also varies with a circadian period. Because this effect can be observed without having to feed the animal to encourage movement we were able to identify what stimulus entrains the circadian oscillation. We show that with reticular-activated recordings started at various times of the day the frequency of theta varies quasi-sinusoidally with a 25 h period and phase-aligned when referenced to the animal’s regular feeding time, but not the recording start time. Furthermore, we show that theta frequency consistently varied with a circadian period when the data obtained from repeated recordings started at various times of the day were referenced to the start of food availability in the recording chamber. This pattern did not occur when data were referenced to the start of the recording session or to the actual time of day when this was not also related to feeding time. This double dissociation demonstrates that hippocampal theta is modulated with a circadian timescale, and that this modulation is strongly entrained by food. One interpretation of this finding is that the hippocampus is responsive to a food entrainable oscillator (FEO) that might modulate foraging behavior over circadian periods.
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Affiliation(s)
- Robert G K Munn
- Department of Psychology, University of Otago Dunedin, New Zealand ; Department of Neurobiology, Stanford University Stanford, CA, USA
| | - Susan M Tyree
- Department of Psychology, University of Otago Dunedin, New Zealand
| | - Neil McNaughton
- Department of Psychology, University of Otago Dunedin, New Zealand
| | - David K Bilkey
- Department of Psychology, University of Otago Dunedin, New Zealand
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27
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Mitra A, Lenglos C, Timofeeva E. Inhibition in the lateral septum increases sucrose intake and decreases anorectic effects of stress. Eur J Neurosci 2014; 41:420-33. [DOI: 10.1111/ejn.12798] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 10/15/2014] [Accepted: 10/31/2014] [Indexed: 12/25/2022]
Affiliation(s)
- Arojit Mitra
- Stress and Feeding Laboratory; IUCPQ; Department of Psychiatry and Neuroscience; Laval University; Quebec QC Canada
| | - Christophe Lenglos
- Stress and Feeding Laboratory; IUCPQ; Department of Psychiatry and Neuroscience; Laval University; Quebec QC Canada
| | - Elena Timofeeva
- Stress and Feeding Laboratory; IUCPQ; Department of Psychiatry and Neuroscience; Laval University; Quebec QC Canada
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28
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Caba M, Pabello M, Moreno ML, Meza E. Main and accessory olfactory bulbs and their projections in the brain anticipate feeding in food-entrained rats. Chronobiol Int 2014; 31:869-77. [PMID: 24915133 DOI: 10.3109/07420528.2014.918625] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The olfactory bulb (OB) has a circadian clock independent of the suprachiasmatic nucleus, but very little is known about the functional significance of its oscillations. The OB plays a major role in food intake as it contributes to the evaluation of the hedonic properties of food, it is necessary for a normal pattern of locomotor behavior and their ablation disrupts feeding patterns. Previously we demonstrated that OB of rabbit pups can be entrained by periodic nursing but it was not clear whether food was the entraining signal. Here we hypothesized that OB can be entrained by a food pulse during the day in adult rats under a restricted feeding schedule. Then we expect that OB will have a high activation before food presentation when animals show food anticipatory activity (FAA). To this aim we determined by immunohistochemistry the expression of FOS protein, as an indicator of neural activation, in the mitral and granular cell layers of the main and accessory OB. Additionally we also explored two of the OB brain targets, the piriform cortex (PC) and bed nuclei of the accessory olfactory tract (BAOT), in three groups: ad libitum (ALF), restricted feeding (RF), and fasted rats after restricted feeding (RF-F). In ALF group FOS levels in both main and accessory OB were low during the day and high during the night at the normal onset of the increase of activity, in agreement with previous reports. On the contrary in RF and RF-F groups FOS was high at the time of FAA, just before food presentation, when animals are in a state of high arousal and during food consumption but was low during the night. In their brain targets, we observed a similar pattern as OB in all groups with the only difference being that FOS levels remained high during the night in RF-F group. We conclude that the OB is entrained by food restriction by showing high activation at the time of food presentation, which persists during fasting and impose a similar FOS pattern to the two brain targets explored only in fed animals.
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Affiliation(s)
- Mario Caba
- Centro de Investigaciones Biomédicas, Universidad Veracruzana , Xalapa, Veracruz , México and
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Lenglos C, Mitra A, Guèvremont G, Timofeeva E. Regulation of expression of relaxin-3 and its receptor RXFP3 in the brain of diet-induced obese rats. Neuropeptides 2014; 48:119-32. [PMID: 24629399 DOI: 10.1016/j.npep.2014.02.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 02/04/2014] [Accepted: 02/13/2014] [Indexed: 02/08/2023]
Abstract
An animal model closely related to human obesity is diet-induced obesity in Sprague-Dawley rats. These rats placed on a high-energy (HE) diet show wide distribution in body weight gain with a subset of animals developing diet-induced obesity (DIO) and the remaining animals showing a diet-resistant (DR) phenotype. Once obesity is established, DIO rats strongly defend their increased body weight against caloric restriction. There is evidence that neuropeptide relaxin-3 is involved in food intake regulation, but the levels of expression of relaxin-3 and its receptor have not been yet demonstrated in the DIO model. The present study investigated the brain expression of relaxin-3 and its cognate receptor RXFP3 in DIO and DR rats maintained on an HE diet since weaning. Expression of relaxin-3 and RXFP3 mRNAs was assessed by in situ hybridization in ad libitum, food-deprived (12 h) and refed (1 h) feeding states. The levels of expression of relaxin-3 in the medial portion of the nucleus incertus (NI) were higher in the DIO rats compared to the DR rats in the ad libitum-fed state. Food deprivation increased the levels of expression of relaxin-3 in the medial NI in DR but not DIO rats. The stronger expression of relaxin-3 in the ad libitum-fed state in the DIO rats was accompanied by low expression of the RXFP3 receptor in the paraventricular hypothalamic nucleus (PVN), supraoptic nucleus, central amygdala (CeA), NI, and nucleus of the solitary tract (NTS). Refeeding increased expression of RXFP3 in the paraventricular thalamic nucleus, parvocellular PVN, CeA, NI, and NTS in the DIO rats. These results provide evidence that DIO rats show a constitutive increase in relaxin-3 expression in the medial NI and that refeeding after food deprivation may enhance the orexigenic effects of relaxin-3 in DIO rats by rapid upregulation of the expression of RXFP3 in the specific brain regions involved in food intake regulation.
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Affiliation(s)
- Christophe Lenglos
- Faculté de Médecine, Département Psychiatrie et Neurosciences, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, QC G1V 4G5, Canada
| | - Arojit Mitra
- Faculté de Médecine, Département Psychiatrie et Neurosciences, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, QC G1V 4G5, Canada
| | - Geneviève Guèvremont
- Faculté de Médecine, Département Psychiatrie et Neurosciences, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, QC G1V 4G5, Canada
| | - Elena Timofeeva
- Faculté de Médecine, Département Psychiatrie et Neurosciences, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, QC G1V 4G5, Canada.
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Gallardo CM, Hsu CT, Gunapala KM, Parfyonov M, Chang CH, Mistlberger RE, Steele AD. Behavioral and neural correlates of acute and scheduled hunger in C57BL/6 mice. PLoS One 2014; 9:e95990. [PMID: 24806659 PMCID: PMC4012955 DOI: 10.1371/journal.pone.0095990] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 04/01/2014] [Indexed: 01/11/2023] Open
Abstract
In rodents, daily feeding schedules induce food anticipatory activity (FAA) rhythms with formal properties suggesting mediation by food-entrained circadian oscillators (FEOs). The search for the neuronal substrate of FEOs responsible for FAA is an active area of research, but studies spanning several decades have yet to identify unequivocally a brain region required for FAA. Variability of results across studies leads to questions about underlying biology versus methodology. Here we describe in C57BL/6 male mice the effects of varying the ‘dose’ of caloric restriction (0%, 60%, 80%, 110%) on the expression of FAA as measured by a video-based analysis system, and on the induction of c-Fos in brain regions that have been implicated in FAA. We determined that more severe caloric restriction (60%) leads to a faster onset of FAA with increased magnitude. Using the 60% caloric restriction, we found little evidence for unique signatures of neuronal activation in the brains of mice anticipating a daily mealtime compared to mice that were fasted acutely or fed ad-libitum–even in regions such as the dorsomedial and ventrolateral hypothalamus, nucleus accumbens, and cerebellum that have previously been implicated in FAA. These results underscore the importance of feeding schedule parameters in determining quantitative features of FAA in mice, and demonstrate dissociations between behavioral FAA and neural activity in brain areas thought to harbor FEOs or participate in their entrainment or output.
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Affiliation(s)
- Christian M. Gallardo
- Division of Biology, California Institute of Technology, Pasadena, California, United States of America
| | - Cynthia T. Hsu
- Division of Biology, California Institute of Technology, Pasadena, California, United States of America
| | - Keith M. Gunapala
- Division of Biology, California Institute of Technology, Pasadena, California, United States of America
| | - Maksim Parfyonov
- Department of Psychology, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Chris H. Chang
- W.M. Keck Science Department, Claremont McKenna College, Pitzer College, Scripps College, Claremont, California, United States of America
| | - Ralph E. Mistlberger
- Department of Psychology, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Andrew D. Steele
- Division of Biology, California Institute of Technology, Pasadena, California, United States of America
- Biological Sciences Department, California State Polytechnic University Pomona, Pomona, California, United States of America
- * E-mail:
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Down-regulation of hypothalamic pro-opiomelanocortin (POMC) expression after weaning is associated with hyperphagia-induced obesity in JCR rats overexpressing neuropeptide Y. Br J Nutr 2013; 111:924-32. [DOI: 10.1017/s0007114513003061] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We hypothesised that hypothalamic feeding-related neuropeptides are differentially expressed in obese-prone and lean-prone rats and trigger overeating-induced obesity. To test this hypothesis, in the present study, we measured energy balance and hypothalamic neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) mRNA expressions in male JCR:LA-cp rats. We compared, in independent cohorts, free-feeding obese-prone (Obese-FF) and lean-prone (Lean-FF) rats at pre-weaning (10 d old), weaning (21–25 d old) and early adulthood (8–12 weeks). A group of Obese-pair-feeding (PF) rats pair-fed to the Lean-FF rats was included in the adult cohort. The body weights of 10-d-old Obese-FF and Lean-FF pups were not significantly different. However, when the pups were shifted from dams' milk to solid food (weaning), the obese-prone rats exhibited more energy intake over the days than the lean-prone rats and higher body and fat pad weights and fasting plasma glucose, leptin, insulin and lipid levels. These differences were consistent with higher energy consumption and lower energy expenditure. In the young adult cohort, the differences between the Obese-FF and Lean-FF rats became more pronounced, yielding significant age effects on most of the parameters of the metabolic syndrome, which were reduced in the Obese-PF rats. The obese-prone rats displayed higher NPY expression than the lean-prone rats at pre-weaning and weaning, and the expression levels did not differ by age. In contrast, POMC expression exhibited significant age-by-genotype differences. At pre-weaning, there was no genotype difference in POMC expression, but in the weanling cohort, obese-prone pups exhibited lower POMC expression than the lean-prone rats. This genotype difference became more pronounced at adulthood. Overall, the development of hyperphagia-induced obesity in obese-prone JCR rats is related to POMC expression down-regulation in the presence of established NPY overexpression.
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Jiménez A, Caba M, Escobar C. Food-entrained patterns in orexin cells reveal subregion differential activation. Brain Res 2013; 1513:41-50. [DOI: 10.1016/j.brainres.2013.03.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 03/19/2013] [Accepted: 03/20/2013] [Indexed: 11/29/2022]
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Rajkumar R, See LKY, Dawe GS. Acute antipsychotic treatments induce distinct c-Fos expression patterns in appetite-related neuronal structures of the rat brain. Brain Res 2013; 1508:34-43. [DOI: 10.1016/j.brainres.2013.02.050] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Revised: 02/23/2013] [Accepted: 02/28/2013] [Indexed: 10/27/2022]
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Lenglos C, Mitra A, Guèvremont G, Timofeeva E. Sex differences in the effects of chronic stress and food restriction on body weight gain and brain expression of CRF and relaxin-3 in rats. GENES BRAIN AND BEHAVIOR 2013; 12:370-87. [PMID: 23425370 DOI: 10.1111/gbb.12028] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 11/05/2012] [Accepted: 02/17/2013] [Indexed: 01/08/2023]
Abstract
This study investigated sex-specific effects of repeated stress and food restriction on food intake, body weight, corticosterone plasma levels and expression of corticotropin-releasing factor (CRF) in the hypothalamus and relaxin-3 in the nucleus incertus (NI). The CRF and relaxin-3 expression is affected by stress, and these neuropeptides produce opposite effects on feeding (anorexigenic and orexigenic, respectively), but sex-specific regulation of CRF and relaxin-3 by chronic stress is not fully understood. Male and female rats were fed ad libitum chow (AC) or ad libitum chow and intermittent palatable liquid Ensure without food restriction (ACE), or combined with repeated food restriction (60% chow, 2 days per week; RCE). Half of the rats were submitted to 1-h restraint stress once a week. In total, seven weekly cycles were applied. The body weight of the RCE stressed male rats significantly decreased, whereas the body weight of the RCE stressed female rats significantly increased compared with the respective control groups. The stressed female RCE rats considerably overate chow during recovery from stress and food restriction. The RCE female rats showed elevated plasma corticosterone levels and low expression of CRF mRNA in the paraventricular hypothalamic nucleus but not in the medial preoptic area. The NI expression of relaxin-3 mRNA was significantly higher in the stressed RCE female rats compared with other groups. An increase in the expression of orexigenic relaxin-3 and misbalanced hypothalamic-pituitary-adrenal axis activity may contribute to the overeating and increased body weight seen in chronically stressed and repeatedly food-restricted female rats.
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Affiliation(s)
- C Lenglos
- Département Psychiatrie et Neurosciences, Faculté de Médecine, Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
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Liu YY, Liu TY, Qu WM, Hong ZY, Urade Y, Huang ZL. Dopamine is involved in food-anticipatory activity in mice. J Biol Rhythms 2013; 27:398-409. [PMID: 23010662 DOI: 10.1177/0748730412455913] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
When food is available during a restricted and predictable time of the day, mammals exhibit food-anticipatory activity (FAA), an increase in locomotor activity preceding the presentation of food. Although many studies have attempted to locate the food-entrainable circadian oscillator in the central nervous system, the pathways that mediate food entrainment are a matter of controversy. The present study was designed to determine the role of dopaminergic and histaminergic systems on FAA. Mice were given access to food for 2 h (ZT12-ZT14), and FAA was defined as the locomotor activity that occurred 2 h before the availability of food. Dopamine D(1) receptor (R), D(2)R, and histamine H(1)R-specific antagonists were used to clarify the role of dopamine and histamine receptors in FAA induced by food restriction (FR). FAA was monitored by infrared locomotor activity sensors. Mice were sacrificed at ZT12 on the 14th day of FR, and monoamine concentrations were determined by high-performance liquid chromatography coupled to electrochemical detection (HPLC-ECD). The results showed that pretreatment with the D(1)R antagonist SCH23390 at 1, 3, or 10 µg/kg significantly reduced FAA by 19% (p < 0.05), 26% (p < 0.05), or 19% (p < 0.01), respectively, and the D(2)R antagonist raclopride at 22, 67, or 200 µg/kg significantly reduced FAA by 16% (p < 0.05), 36% (p < 0.01), or 41% (p < 0.01), respectively, as compared with vehicle control. Moreover, coadministration of SCH23390 (10 µg/kg) and raclopride (200 µg/kg) synergistically inhibited FAA by 57% (p < 0.01) as compared with vehicle control. Consistently, the levels of dopamine and its metabolites in the striatum and midbrain were significantly increased during FAA, even with the pretreatment of D(1)R and D(2)R antagonists. However, pretreatment with pyrilamine at 2.5, 5, or 10 mg/kg did not significantly reduce FAA, although it reduced the locomotor activity during the dark period in ad libitum mice. These results strongly indicate that the dopaminergic system plays an essential role in the FAA in mice.
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Affiliation(s)
- Yuan-Yuan Liu
- Department of Pharmacology, Shanghai Medical College, Fudan University, Shanghai, China
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Merkestein M, Verhagen LAW, Adan RAH. Food-Anticipatory Activity: Rat Models and Underlying Mechanisms. NEUROMETHODS 2013. [DOI: 10.1007/978-1-62703-104-2_18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Abstract
Mammals exhibit daily anticipatory activity to cycles of food availability. Studies on such food anticipatory activity (FAA) have been conducted mainly in nocturnal rodents. They have identified FAA as the behavioral output of a food entrained oscillator (FEO), separate of the known light entrained oscillator (LEO) located in the suprachiasmatic nucleus (SCN) of hypothalamus. Here we briefly review the main characteristics of FAA. Also, we present results on four topics of food anticipation: (1) possible input signals to FEO, (2) FEO substrate, (3) the importance of canonical clock genes for FAA, and (4) potential practical applications of scheduled feeding. This mini review is intended to introduce the subject of food entrainment to those unfamiliar with it but also present them with relevant new findings on the issue.
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Affiliation(s)
- Breno T S Carneiro
- Departamento de Ciências Animais, Universidade Federal Rural do Semi-Árido Mossoró, Brazil ; Programa de Pós-Graduação em Psicobiologia, Universidade Federal do Rio Grande do Norte Natal, Brazil
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Diane A, Pierce WD, Heth CD, Russell JC, Richard D, Proctor SD. Feeding history and obese-prone genotype increase survival of rats exposed to a challenge of food restriction and wheel running. Obesity (Silver Spring) 2012; 20:1787-95. [PMID: 22016097 DOI: 10.1038/oby.2011.326] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We hypothesized that obese-prone genotype and history of food restriction confer a survival advantage to genetically obese animals under environmental challenge. Male juvenile JCR:LA-cp rats, obese-prone and lean-prone, were exposed to 1.5 h daily meals and 22.5-h voluntary wheel running, a procedure inducing activity anorexia (AA). One week before the AA challenge, obese-prone rats were freely fed (obese-FF), or pair fed (obese-PF) to lean-prone, free-feeding rats (lean-FF). Animals were removed from protocol at 75% of initial body weight (starvation criterion) or after 14 days (survival criterion). AA challenge induced weight loss in all rats, but percent weight loss was more rapid and sustained in lean-FF rats than in obese-FF or obese-PF animals (P < 0.04). Weight loss was significantly higher in obese-FF rats than obese-PF rats, 62% of which achieved survival criterion and stabilized with zero weight loss. Obese-PF rats survived longer, on average (12.0 ± 1.1 day) than obese-FF (8.2 ± 1.1 day) and lean-FF rats (3.5 ± 0.2 day) (P < 0.02). Wheel running increased linearly in all groups; lean-FF increased more rapidly than obese-FF (P < 0.05); obese-PF increased at an intermediate rate (P < 0.02), and those rats that survived stabilized daily rates of wheel running. Prior food restriction of juvenile obese-prone rats induces a survival benefit beyond genotype, that is related to achievement of homeostasis. This metabolic adaptive process may help explain the development of human obesity in the presence of an unstable food environment which subsequently transitions to an abundant food supply.
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Affiliation(s)
- Abdoulaye Diane
- Metabolic and Cardiovascular Diseases Laboratory, Alberta Diabetes Institute University of Alberta, Edmonton, Alberta, Canada
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Badonnel K, Lacroix MC, Monnerie R, Durieux D, Caillol M, Baly C. Chronic restricted access to food leading to undernutrition affects rat neuroendocrine status and olfactory-driven behaviors. Horm Behav 2012; 62:120-7. [PMID: 22633909 DOI: 10.1016/j.yhbeh.2012.05.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 05/16/2012] [Accepted: 05/17/2012] [Indexed: 01/08/2023]
Abstract
Previous studies have demonstrated that olfactory-driven behaviors in rats are influenced by short-term caloric restriction, partly through the modulation of olfactory sensitivity by appetite-modulating hormones or peptides such as insulin and leptin. Here, we addressed the issue of a long-term modulation of their neuroendocrine status by evaluating the effect of chronic food restriction in rats following a limitation of the duration of daily food intake to 2 h (SF) instead of 8 h (LF) on the expression of insulin and leptin system in the olfactory mucosa and bulb and on olfactory behaviors. This restriction resulted in a one-third reduction in the daily food intake and a 25% reduction in the body weight of SF rats when compared to controls, and was accompanied by lower levels of triglycerides, glucose, insulin and leptin in SF rats. Under these conditions, we observed a modulation of olfactory-mediated behaviors regarding food odors. In addition, restriction had a differential effect on the expression of insulin receptors, but not that of leptin receptors, in the olfactory mucosa, whereas no transcriptional change was observed at the upper level of the olfactory bulb. Overall, these data demonstrated that long-term changes in nutritional status modulate olfactory-mediated behaviors. Modulation of insulin system expression in the olfactory mucosa of food restricted rats suggests that this hormone could be part of this process.
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Affiliation(s)
- Karine Badonnel
- INRA, UR1197, Neurobiologie de l'Olfaction et Modélisation en Imagerie, 78350 Jouy-en-Josas, France
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Renner E, Puskás N, Dobolyi A, Palkovits M. Glucagon-like peptide-1 of brainstem origin activates dorsomedial hypothalamic neurons in satiated rats. Peptides 2012; 35:14-22. [PMID: 22401907 DOI: 10.1016/j.peptides.2012.02.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 02/21/2012] [Accepted: 02/21/2012] [Indexed: 01/01/2023]
Abstract
A high number of neurons express c-fos in response to unlimited food intake in fasted rats in the ventral subdivision of the hypothalamic dorsomedial nucleus (DMHv). We report here, that in same conditions, limited food consumption failed to induce Fos expression in DMHv neurons suggesting that satiation should be one of the important signals that activate these neurons. The possible origin of fibers conducting satiation signals to the DMHv could be in the lower brainstem, especially glucagon-like peptide-1 (GLP-1)-containing neurons in the nucleus of the solitary tract (NTS). We demonstrate that GLP-1-immunoreactive fibers and fiber terminals topographically overlap with activated Fos-positive neurons in the DMHv in refed rats. Using immunocytochemistry and in situ hybridization histochemistry, we demonstrated GLP-1 receptors in Fos-expressing neurons of the DMH. Unilateral transections of ascending GLP-1-containing fibers from the NTS inside the pons in refed rats (unlimited food consumption) resulted in a dramatic decrease in the density of GLP-1 fibers and in the number of Fos-immunoreactive neurons in the DMHv, but only on the side of the transection. Contralateral to the transection, neither the GLP-1 fiber density nor the number of Fos-positive cells changed significantly. Meanwhile, the density of GLP-1 immunoreactivity was markedly accumulated in transected nerve fibers caudal to the cuts, as a consequence of the interruption of the ascending GLP-1 transport route. These findings suggest that the solitary-hypothalamic projections may represent the neuronal route through GLP-1 neurons of the NTS activate DMHv neurons via GLP-1 receptors by conveying information on satiety.
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Affiliation(s)
- E Renner
- Neuromorphological and Neuroendocrine Research Laboratory, Department of Anatomy, Semmelweis University, Budapest H-1094, Hungary
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Blum ID, Waddington Lamont E, Rodrigues T, Abizaid A. Isolating neural correlates of the pacemaker for food anticipation. PLoS One 2012; 7:e36117. [PMID: 22558352 PMCID: PMC3338627 DOI: 10.1371/journal.pone.0036117] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Accepted: 03/30/2012] [Indexed: 11/23/2022] Open
Abstract
Mice fed a single daily meal at intervals within the circadian range exhibit food anticipatory activity. Previous investigations strongly suggest that this behaviour is regulated by a circadian pacemaker entrained to the timing of fasting/refeeding. The neural correlate(s) of this pacemaker, the food entrainable oscillator (FEO), whether found in a neural network or a single locus, remain unknown. This study used a canonical property of circadian pacemakers, the ability to continue oscillating after removal of the entraining stimulus, to isolate activation within the neural correlates of food entrainable oscillator from all other mechanisms driving food anticipatory activity. It was hypothesized that continued anticipatory activation of central nuclei, after restricted feeding and a return to ad libitum feeding, would elucidate a neural representation of the signaling circuits responsible for the timekeeping component of the food entrainable oscillator. Animals were entrained to a temporally constrained meal then placed back on ad libitum feeding for several days until food anticipatory activity was abolished. Activation of nuclei throughout the brain was quantified using stereological analysis of c-FOS expressing cells and compared against both ad libitum fed and food entrained controls. Several hypothalamic and brainstem nuclei remained activated at the previous time of food anticipation, implicating them in the timekeeping mechanism necessary to track previous meal presentation. This study also provides a proof of concept for an experimental paradigm useful to further investigate the anatomical and molecular substrates of the FEO.
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Affiliation(s)
| | | | | | - Alfonso Abizaid
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
- * E-mail:
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Dailey MJ, Stingl KC, Moran TH. Disassociation between preprandial gut peptide release and food-anticipatory activity. Endocrinology 2012; 153:132-42. [PMID: 22128024 PMCID: PMC3249668 DOI: 10.1210/en.2011-1464] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Animals learn to anticipate a meal as evidenced by increases in premeal activity. This learned response appears to be independent of the nutrient status of an animal because food-anticipatory activity (FAA) can be seen after entrainment by a highly palatable food when rats remain ad libitum on chow. Mealtime feeding not only induces an increase in activity but also appears to entrain the secretion of various peptides prior to a meal including insulin, ghrelin, and glucagon-like peptide-1 (GLP-1). It is not clear whether these meal-anticipatory changes in peptides are causally associated with FAA. To assess whether FAA and preprandial peptide changes co-occur with meal entrainment using different diets, rats were conditioned to receive a 6-h chow meal, 6-h high-fat meal, or 2 h access of chocolate while ad libitum on chow in the middle of the light cycle. FAA was measured for 4 h prior to mealtime. Rats were then killed at 90, 60, and 30 min prior to mealtime and plasma was collected. Although the chocolate-entrained rats showed comparable FAA with the nonchocolate-entrained animals, they did not show anticipatory increases in the ghrelin or GLP-1. All entrainment conditions induced a decrease in insulin and an increase in glucose prior to mealtime. These data suggest that separate mechanisms may underlie the preprandial increases in ghrelin and GLP-1 and changes in FAA, insulin, and glucose.
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Affiliation(s)
- Megan J Dailey
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Ross 618, Baltimore, Maryland 21205, USA.
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Kuenzel WJ, Medina L, Csillag A, Perkel DJ, Reiner A. The avian subpallium: new insights into structural and functional subdivisions occupying the lateral subpallial wall and their embryological origins. Brain Res 2011; 1424:67-101. [PMID: 22015350 PMCID: PMC3378669 DOI: 10.1016/j.brainres.2011.09.037] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Revised: 09/16/2011] [Accepted: 09/17/2011] [Indexed: 12/18/2022]
Abstract
The subpallial region of the avian telencephalon contains neural systems whose functions are critical to the survival of individual vertebrates and their species. The subpallial neural structures can be grouped into five major functional systems, namely the dorsal somatomotor basal ganglia; ventral viscerolimbic basal ganglia; subpallial extended amygdala including the central and medial extended amygdala and bed nuclei of the stria terminalis; basal telencephalic cholinergic and non-cholinergic corticopetal systems; and septum. The paper provides an overview of the major developmental, neuroanatomical and functional characteristics of the first four of these neural systems, all of which belong to the lateral telencephalic wall. The review particularly focuses on new findings that have emerged since the identity, extent and terminology for the regions were considered by the Avian Brain Nomenclature Forum. New terminology is introduced as appropriate based on the new findings. The paper also addresses regional similarities and differences between birds and mammals, and notes areas where gaps in knowledge occur for birds.
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Affiliation(s)
- Wayne J Kuenzel
- Department of Poultry Science, Poultry Science Center, University of Arkansas, Fayetteville, Arkansas 72701, USA.
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Munn RG, Bilkey DK. The firing rate of hippocampal CA1 place cells is modulated with a circadian period. Hippocampus 2011; 22:1325-37. [DOI: 10.1002/hipo.20969] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2011] [Indexed: 01/30/2023]
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Roy C, Roy MC, Gauvreau D, Poulin AM, Tom FQ, Timofeeva E, Richard D, Cianflone K. Acute injection of ASP in the third ventricle inhibits food intake and locomotor activity in rats. Am J Physiol Endocrinol Metab 2011; 301:E232-41. [PMID: 21540449 DOI: 10.1152/ajpendo.00476.2010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Acylation-stimulating protein (ASP; also known as C3adesArg) stimulates triglyceride synthesis and glucose transport via interaction with its receptor C5L2, which is expressed peripherally (adipose tissue, muscle) and centrally. Previous studies have shown that ASP-deficient mice (C3KO) and C5L2-deficient mice (C5L2KO) are hyperphagic (59 to 229% increase, P < 0.0001), which is counterbalanced by increased energy expenditure measured as oxygen consumption (Vo(2)) and a lower RQ. The aim of the present study was to evaluate ASP's effect on food intake, energy expenditure, and neuropeptide expression. Male rats were surgically implanted with intracerebroventricular (icv) cannulas directed toward the third ventricle. After a 5-h fast, rats were injected, and food intake was assessed at 0.5, 1, 2, 4, 16, 24, and 48 h, with a 5- to 7-day washout period between each injection. Acute icv injections of ASP (0.3-1,065 pmol) had a time-dependent effect on decreasing food intake by 20 to 57% (P < 0.05). Decreases were detected by 30 min (maximum 57%, P < 0.01) and at the highest dose effects extended to 48 h (19%, P < 0.05, 24- to 48-h period). Daily body weight gain was decreased by 131% over the first 24 h and 29% over the second 24 h (P < 0.05). A conditioned taste aversion test indicated that there was no malaise. Furthermore, acute ASP injection affected energy substrate usage, demonstrated by decreased Vo(2) and RQ (P < 0.05; implicating greater fatty acid usage), with a 49% decrease in total activity over 24 h (P < 0.05). ASP administration also increased anorexic neuropeptide POMC expression (44%) in the arcuate nucleus, with no change in NPY. Altogether ASP may have central in addition to peripheral effects.
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Affiliation(s)
- Christian Roy
- Centre de Recherche Institut Universitaire de Cardiologie et Pneumologie de Québec, Sainte-Foy, Quebec, Canada
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Mitra A, Lenglos C, Martin J, Mbende N, Gagné A, Timofeeva E. Sucrose modifies c-fos mRNA expression in the brain of rats maintained on feeding schedules. Neuroscience 2011; 192:459-74. [PMID: 21718761 DOI: 10.1016/j.neuroscience.2011.06.033] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Revised: 05/19/2011] [Accepted: 06/10/2011] [Indexed: 11/25/2022]
Abstract
Food intake is regulated according to circadian activity, metabolic needs and the hedonic value of food. Rodents placed on a fixed feeding schedule show behavioral and physiological anticipation of mealtime referred to as food-anticipatory activity (FAA). FAA is driven by the food-entrainable oscillator (FEO), whose anatomical substrate is not yet known. Recent data have shown that restricted feeding schedules for regular chow and daily limited access to palatable food in free-feeding rats activate distinct brain regions during FAA. The combination of a deprivation regimen and scheduled access to palatable food may give rise to a more global anticipatory mechanism because the temporal cycles of energy balance would be strongly modulated by the incentive properties of palatable food; however, the neuronal response to this combined treatment is not yet known. The present study investigated how adding palatable sucrose to feeding schedules affects the pattern of brain c-fos mRNA expression during FAA (0-3 h) and 1 h following feeding. The rats maintained on scheduled chow access increased their daily chow intake, while the rats maintained on scheduled sucrose and chow mainly increased their daily sucrose intake. Adding sucrose to scheduled feeding displaced c-fos mRNA expression from the dorsomedial and paraventricular hypothalamic nuclei and posterior lateral hypothalamus (LH) to the prefrontal cortex, lateral septum, nucleus accumbens and anterior LH. During refeeding, the rats on scheduled sucrose demonstrated higher activation of the nucleus of the solitary tract. The present results suggest that palatable sucrose combined with restricted feeding schedules activate a distinct neuronal network compared to neuronal activation produced by scheduled access to regular chow. These data provide evidence that the brain may contain different food-oscillatory systems and that food palatability may shift the neuronal activity from the medial hypothalamus to the limbic and reward-related areas even at the negative metabolic state.
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Affiliation(s)
- A Mitra
- Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Faculty of Medicine, Department of Psychiatry and Neuroscience, Université Laval, Québec (QC), G1V 4G5, Canada
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Nucleus incertus--an emerging modulatory role in arousal, stress and memory. Neurosci Biobehav Rev 2011; 35:1326-41. [PMID: 21329721 DOI: 10.1016/j.neubiorev.2011.02.004] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 02/01/2011] [Accepted: 02/08/2011] [Indexed: 01/09/2023]
Abstract
A major challenge in systems neuroscience is to determine the underlying neural circuitry and associated neurotransmitters and receptors involved in psychiatric disorders, such as anxiety and depression. A focus of many of these studies has been specific brainstem nuclei that modulate levels of arousal via their ascending monoaminergic projections (e.g. the serotonergic dorsal raphé, noradrenergic locus ceruleus and cholinergic laterodorsal tegmental nucleus). After years of relative neglect, the subject of recent studies in this context has been the GABAergic nucleus incertus, which is located in the midline periventricular central gray in the 'prepontine' hindbrain, with broad projections throughout the forebrain. Nucleus incertus neurons express receptors for the stress hormone, corticotropin-releasing factor (CRF), are activated by psychological stressors, and project to key nuclei involved in stress responses and behavioral activation. The nucleus incertus is also a node in neural circuits capable of modulating hippocampal theta rhythm, which is related to control of spatial navigation and memory. A significant population of nucleus incertus neurons express the recently discovered, highly conserved neuropeptide, relaxin-3; and the recent availability of structurally-related, chimeric peptides that selectively activate or inhibit the relaxin-3 receptor, RXFP3, is facilitating studies of relaxin-3/RXFP3 networks and associated GABA and CRF systems. It is predicted that such targeted research will help elucidate the functions of ascending nucleus incertus pathways, including their possible involvement in arousal (sleep/wakefulness), stress reponses, and learning and memory; and in the pathology of related psychiatric diseases such as insomnia, anxiety and depression, and cognitive deficits.
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Davis JF, Choi DL, Clegg DJ, Benoit SC. Signaling through the ghrelin receptor modulates hippocampal function and meal anticipation in mice. Physiol Behav 2010; 103:39-43. [PMID: 21036184 DOI: 10.1016/j.physbeh.2010.10.017] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Revised: 10/19/2010] [Accepted: 10/20/2010] [Indexed: 11/18/2022]
Abstract
The ability to predict a particular meal is achieved in part by learned associations with stimuli that predict nutrient availability. Ghrelin is an orexigenic peptide produced by both the gut and brain that rises before anticipated meals and it has been suggested that pre-prandial ghrelin increases may act as a signal to predict meal delivery. Here, we used wild type and ghrelin receptor deficient mice to test the hypothesis that ghrelin signaling is necessary for the processing of emotionally relevant stimuli, spatial learning and habituated feeding responses. We tested spatial and fear-related memory with the Morris water maze and step through passive avoidance tests, respectively and utilized food anticipatory activity to monitor habituated feeding responses following two weeks of a meal feeding paradigm. Our results indicate that ghrelin signaling modulates spatial memory performance and is necessary for the development of food anticipatory activity. Collectively, these results suggest that ghrelin receptor signaling is necessary for adaptations in the anticipatory responses that accompany restricted feeding.
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Affiliation(s)
- Jon F Davis
- University of Cincinnati, Department of Psychiatry, Cincinnati, OH, USA.
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Challet E, Mendoza J. Metabolic and reward feeding synchronises the rhythmic brain. Cell Tissue Res 2010; 341:1-11. [DOI: 10.1007/s00441-010-1001-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Accepted: 05/28/2010] [Indexed: 12/28/2022]
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Abstract
Many daily cycles are imposed on us by our environment, such as alternating days and nights, temperature fluctuations or rhythms in food availability. When food is accessible every day at the same time, animals will adapt their physiology and behaviour to match the daily meal. They will anticipate the access to food by waking up and being active in the hours prior to feeding, foraging for food. Adaptation of physiology to changing conditions of food availability is not only evident at the behavioural level, but also for hormonal systems. Thus, corticosteroids, melatonin, leptin/ghrelin, insulin/glucagon, orexins and thyroid hormones, which show rhythmic profiles of secretion in ad libitum feeding conditions, are sensitive to increase and/or depletion in energy supplies and will be influenced when food sources are limited or available at unusual times. The present review reports the influence of restricted feeding schedules on secretion profiles of diverse hormones compared to normal ad libitum feeding conditions in rodents. In the end, the interplay between these systems and their response to environmental challenges will allow the animal to maintain their fitness for survival.
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Affiliation(s)
- C A Feillet
- Division of Biochemistry, Department of Medicine, University of Fribourg, Fribourg, Switzerland.
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