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Food anticipatory circadian rhythms in mice entrained to long or short day photoperiods. Physiol Behav 2020; 222:112939. [PMID: 32407832 DOI: 10.1016/j.physbeh.2020.112939] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 04/03/2020] [Accepted: 04/23/2020] [Indexed: 11/21/2022]
Abstract
Food anticipatory activity (FAA) rhythms that emerge in nocturnal rodents fed once daily are mediated by food-entrainable circadian oscillators (FEOs) located outside of the suprachiasmatic nucleus (SCN), the site of a circadian pacemaker required for entrainment to daily light-dark (LD) cycles. Specification of the neural and molecular substrates of FEOs driving FAA is complicated by homeostatic, hedonic and environmental factors that can modulate expression of activity independent of circadian timing. Here, we examined the effect of photoperiod (duration of the daily light period) on FAA in mice fed during the last 4 h or middle 4 h of the light period for at least 5 weeks. Long photoperiods decrease SCN pacemaker amplitude, which may favor expression of FAA during the day, when the SCN normally opposes activity in nocturnal rodents. To test this prediction, in Experiment 1, mice housed with or without running discs were entrained to 24 h LD cycles with 8 h (L8) or 16 h (L16) photoperiods. When food was restricted to the last 4 h of the light period (late-day), mice housed with running discs showed more FAA in L16, whereas mice without running discs showed more FAA in L8. In Experiment 2, mice were entrained to L8 or L16 photoperiods, and the 4 h daily meal was centered in the light period (mid-day). FAA was decreased relative to late-day fed mice, but did not vary by photoperiod. In Experiment 3, mice with or without running discs were entrained to L12 or L18 photoperiods, with mealtime centered in the light period. FAA again did not differ between photoperiods. In constant dark (DD) prior to food restriction, the period (τ) of free-running rhythms was shorter in mice entrained to long days. This known after-effect of photoperiod on τ was absent in DD immediately following restricted feeding. The phase of LD entrainment, unmasked on the first day of DD with food ad-libitum, was significantly advanced in mice from the late-day feeding schedule, compared to mice from the mid-day schedules. These results indicate that FAA in mice does not vary systematically with photoperiod, possibly because daytime feeding schedules attenuate the effect of photoperiod on the mouse SCN pacemaker. FAA in the present study was more strongly influenced by running disc availability and by meal time within the light period, possibly due to effects on LD entrainment, which was phase advanced by late-day but not midday feeding.
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2
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Abstract
Feeding schedules entrain circadian clocks in multiple brain regions and most peripheral organs and tissues, thereby synchronizing daily rhythms of foraging behavior and physiology with times of day when food is most likely to be found. Entrainment of peripheral clocks to mealtime is accomplished by multiple feeding-related signals, including absorbed nutrients and metabolic hormones, acting in parallel or in series in a tissue-specific fashion. Less is known about the signals that synchronize circadian clocks in the brain with feeding time, some of which are presumed to generate the circadian rhythms of food-anticipatory activity that emerge when food is restricted to a fixed daily mealtime. In this commentary, I consider the possibility that food-anticipatory activity rhythms are driven or entrained by circulating ghrelin, ketone bodies or insulin. While evidence supports the potential of these signals to participate in the induction or amount of food-anticipatory behavior, it falls short of establishing either a necessary or sufficient role or accounting for circadian properties of anticipatory rhythms. The availability of multiple, circulating signals by which circadian oscillators in many brain regions might entrain to mealtime has supported a view that food-anticipatory rhythms of behavior are mediated by a broadly distributed system of clocks. The evidence, however, does not rule out the possibility that multiple peripheral and central food-entrained oscillators and feeding-related signals converge on circadian oscillators in a defined location which ultimately set the phase and gate the expression of anticipatory activity rhythms. A candidate location is the dorsal striatum, a core component of the neural system which mediates reward, motivation and action and which contains circadian oscillators entrainable by food and dopaminergic drugs. Systemic metabolic signals, such as ghrelin, ketones and insulin, may participate in circadian food anticipation to the extent that they modulate dopamine afferents to circadian clocks in this area.
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Affiliation(s)
- Ralph E Mistlberger
- Department of Psychology, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A2S6, Canada
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3
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LeSauter J, Balsam PD, Simpson EH, Silver R. Overexpression of striatal D2 receptors reduces motivation thereby decreasing food anticipatory activity. Eur J Neurosci 2018; 51:71-81. [PMID: 30362616 DOI: 10.1111/ejn.14219] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 09/13/2018] [Accepted: 10/04/2018] [Indexed: 12/20/2022]
Abstract
Dopamine has been implicated in circadian timing underlying the food entrainable oscillator (FEO) circuitry and overexpression of the dopamine D2 receptor (D2R) in the striatum has been reported to reduce motivation to obtain food rewards in operant tasks. In the present study, we explored both of these mechanisms by examining food anticipatory activity (FAA) in dopamine D2 receptor-overexpressing (D2R-OE) mice under various durations of food availability. First, we noted that at baseline, there were no differences between D2R-OE mice and their littermates in activity level, food intake, and body weight or in circadian activity. Under conditions of very restricted food availability (4 or 6 hr), both genotypes displayed FAA. In contrast, under 8-hr food availability, control mice showed FAA, but D2R-OE mice did not. Normalization of D2R by administration of doxycycline, a tetracycline analogue, rescued FAA under 8-hr restricted food. We next tested for circadian regulation of FAA. When given ad libitum access to food, neither D2R-OE nor controls were active during the daytime. However, after an interval of food restriction, all mice showed elevated locomotor activity at the time of previous food availability in the day, indicating circadian timing of anticipatory activity. In summary, motivation is reduced in D2R-OE mice but circadian timing behavior is not affected. We conclude that an increase in striatal D2R reduces FAA by modulating motivation and not by acting on a clock mechanism.
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Affiliation(s)
- Joseph LeSauter
- Department of Psychology, Barnard College, New York City, New York
| | - Peter D Balsam
- Department of Psychology, Barnard College, New York City, New York.,Department of Psychiatry, Columbia University, New York City, New York.,New York State Psychiatric Institute, New York City, New York
| | - Eleanor H Simpson
- Department of Psychiatry, Columbia University, New York City, New York.,New York State Psychiatric Institute, New York City, New York
| | - Rae Silver
- Department of Psychology, Barnard College, New York City, New York.,Departments of Psychology and of Pathology and Cell Biology, Columbia University, New York City, New York
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4
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Shrestha TC, Šuchmanová K, Houdek P, Sumová A, Ralph MR. Implicit time-place conditioning alters Per2 mRNA expression selectively in striatum without shifting its circadian clocks. Sci Rep 2018; 8:15547. [PMID: 30341352 PMCID: PMC6195625 DOI: 10.1038/s41598-018-33637-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 10/02/2018] [Indexed: 11/30/2022] Open
Abstract
Animals create implicit memories of the time of day that significant events occur then anticipate the recurrence of those conditions at the same time on subsequent days. We tested the hypothesis that implicit time memory for daily encounters relies on the setting of the canonical circadian clockwork in brain areas involved in the formation or expression of context memories. We conditioned mice to avoid locations paired with a mild foot shock at one of two Zeitgeber times set 8 hours apart. Place avoidance was exhibited only when testing time matched the prior training time. The suprachiasmatic nucleus, dorsal striatum, nucleus accumbens, cingulate cortex, hippocampal complex, and amygdala were assessed for clock gene expression. Baseline phase dependent differences in clock gene expression were found in most tissues. Evidence for conditioned resetting of a molecular circadian oscillation was found only in the striatum (dorsal striatum and nucleus accumbens shell), and specifically for Per2 expression. There was no evidence of glucocorticoid stress response in any tissue. The results are consistent with a model where temporal conditioning promotes a selective Per2 response in dopamine-targeted brain regions responsible for sensorimotor integration, without resetting the entire circadian clockwork.
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Affiliation(s)
- Tenjin C Shrestha
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Karolína Šuchmanová
- Department of Neurohumoral Regulations, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Pavel Houdek
- Department of Neurohumoral Regulations, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Alena Sumová
- Department of Neurohumoral Regulations, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Martin R Ralph
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada.
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5
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Gavrila AM, Hood S, Robinson B, Amir S. Effects of bilateral anterior agranular insula lesions on food anticipatory activity in rats. PLoS One 2017; 12:e0179370. [PMID: 28594962 PMCID: PMC5464650 DOI: 10.1371/journal.pone.0179370] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 05/30/2017] [Indexed: 01/06/2023] Open
Abstract
Food anticipatory activity (FAA) refers to a daily rhythm of locomotor activity that emerges under conditions of food restriction, whereby animals develop an intense, predictable period of activity in the few hours leading up to a predictable, daily delivery of food. The neural mechanisms by which FAA is regulated are not yet fully understood. Although a number of brain regions appear to be involved in regulating the development and expression of FAA, there is little evidence to date concerning the role of the anterior agranular insular cortex (AICa). The AICa plays a critical role in integrating the perception of visceral states with motivational behaviour such as feeding. We assessed the effect of bilateral electrolytic or ibotenic acid lesions of the AICa on FAA in male Wistar rats receiving food for varying lengths of time (2 h, 3 h, or 5 h) during the middle of the light phase (starting at either ZT4 or ZT6). Contrary to our initial expectations, we found that both electrolytic and ibotenic acid lesions significantly increased, rather than decreased, the amount of FAA expressed in lesioned rats. Despite increased FAA, lesioned rats did not eat significantly more during restricted feeding (RF) periods than control rats. Similar to controls, AlCa-lesioned rats showed negligible anticipatory activity to a restricted treat suggesting that the increased anticipatory activity in lesioned rats is associated with food restriction, rather than the appetitive value of the meal. Monitoring behaviour in an open field indicated that increased FAA in AlCa-lesioned rats was not explained by a general increase in locomotor activity. Together, these findings suggest that the AICa contributes to the network of brain regions involved in FAA.
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Affiliation(s)
- Alex M. Gavrila
- Department of Psychology, Center for Studies in Behavioural Neurobiology/FRSQ Groupe de Recherche en Neurobiologie Comportementale, Concordia University, Montreal, Quebec, Canada
| | - Suzanne Hood
- Department of Psychology, Bishop's University, Sherbrooke, Quebec, Canada
| | - Barry Robinson
- Department of Psychology, Center for Studies in Behavioural Neurobiology/FRSQ Groupe de Recherche en Neurobiologie Comportementale, Concordia University, Montreal, Quebec, Canada
| | - Shimon Amir
- Department of Psychology, Center for Studies in Behavioural Neurobiology/FRSQ Groupe de Recherche en Neurobiologie Comportementale, Concordia University, Montreal, Quebec, Canada
- * E-mail:
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6
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Luna-Illades C, Morales T, Miranda-Anaya M. Decreased food anticipatory activity of obese mice relates to hypothalamic c-Fos expression. Physiol Behav 2017; 179:9-15. [PMID: 28527681 DOI: 10.1016/j.physbeh.2017.05.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 05/04/2017] [Accepted: 05/16/2017] [Indexed: 12/17/2022]
Abstract
During daily Food Restriction (FR), obese Neotomodon alstoni mice present decreased Food Anticipatory Activity (FAA) compared to lean mice. Here, we investigated whether FOS expression in hypothalamic nuclei involved in food synchronization and anticipation parallels decreased FAA during daily FR of obese N. alstoni. Locomotor activity of lean and obese mice in ad libitum feeding conditions was monitored for at least two weeks. Then, a gradual restriction of food access was followed to establish a 5h period of daily food access. FR was maintained during at least two weeks before sacrifice of mice at the starting point of the feeding period. Obese mice subjected to FR displayed an overall reduction of FOS-positive (FOS+) hypothalamic neurons, while lean mice in a similar protocol exhibited an increase in FOS+ neurons within the arcuate and dorsomedial hypothalamic nuclei. These results are consistent with decreased FAA displayed by obese mice in comparison to lean mice. Furthermore, limbic system areas of lean mice, such as the cingulate cortex and the hippocampus, showed an increase in FOS during FR, while no responses were observed in obese mice. The daily food intake of obese mice was severely reduced during FR, compared to the ad libitum condition, whereas food intake in lean mice was not affected by FR. Current data suggests that decreased hypothalamic and limbic neuronal activation may contribute to the reduction of FAA in obese N. alstoni mice.
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Affiliation(s)
- C Luna-Illades
- Unidad Multidisciplinaria de Docencia e Investigación, Facultad de Ciencias, Querétaro, Mexico; Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México
| | - T Morales
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México.
| | - M Miranda-Anaya
- Unidad Multidisciplinaria de Docencia e Investigación, Facultad de Ciencias, Querétaro, Mexico
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Cain SW, Rawashdeh OA, Siu M, Kim SC, Ralph MR. Dopamine dependent setting of a circadian oscillator underlying the memory for time of day. Neurobiol Learn Mem 2017; 141:78-83. [PMID: 28366864 DOI: 10.1016/j.nlm.2017.03.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Revised: 03/17/2017] [Accepted: 03/23/2017] [Indexed: 01/15/2023]
Abstract
Animals learn and remember the time of day that significant conditions occur, and anticipate recurrence at 24-h intervals, even after only one exposure to the condition. On several place-conditioning tasks, animals show context avoidance or preference only near the time of day of the experience. The memory for time of day is registered by a circadian oscillator that is set at the time of the training. We show that manipulations of dopamine (DA) neurotransmission can set a time memory in place preference and avoidance tasks, indicating that time of day is part of the context that is learned. Single injections of the DA agonist, d-amphetamine sulfate given without further exposure to the conditioning apparatus, can reset the timing of anticipatory behavior evoked by previously acquired place-event associations. The data support a model for time memory in which DA signaling sets the phase of a circadian oscillator, which returns to the same state at regular 24-h intervals. The data also raise the possibility that some apparent impairments of memory formation or retention could reflect post-experience resetting of the optimal retrieval time rather than impairment of memory or retrieval per se.
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Affiliation(s)
- Sean W Cain
- Centre for Biological Timing and Cognition, Department of Psychology, University of Toronto, 100 St. George Street, Toronto, Ontario M5S 3G3, Canada
| | - Omar A Rawashdeh
- Centre for Biological Timing and Cognition, Department of Psychology, University of Toronto, 100 St. George Street, Toronto, Ontario M5S 3G3, Canada
| | - Michael Siu
- Centre for Biological Timing and Cognition, Department of Psychology, University of Toronto, 100 St. George Street, Toronto, Ontario M5S 3G3, Canada
| | - Seung Cheol Kim
- Centre for Biological Timing and Cognition, Department of Psychology, University of Toronto, 100 St. George Street, Toronto, Ontario M5S 3G3, Canada
| | - Martin R Ralph
- Centre for Biological Timing and Cognition, Department of Psychology, University of Toronto, 100 St. George Street, Toronto, Ontario M5S 3G3, Canada.
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8
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Opiol H, de Zavalia N, Delorme T, Solis P, Rutherford S, Shalev U, Amir S. Exploring the role of locomotor sensitization in the circadian food entrainment pathway. PLoS One 2017; 12:e0174113. [PMID: 28301599 PMCID: PMC5354457 DOI: 10.1371/journal.pone.0174113] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 03/03/2017] [Indexed: 01/23/2023] Open
Abstract
Food entrainment is the internal mechanism whereby the phase and period of circadian clock genes comes under the control of daily scheduled food availability. Food entrainment allows the body to efficiently realign the internal timing of behavioral and physiological functions such that they anticipate food intake. Food entrainment can occur with or without caloric restriction, as seen with daily schedules of restricted feeding (RF) or restricted treat (RT) that restrict food or treat intake to a single feeding time. However, the extent of clock gene control is more pronounced with caloric restriction, highlighting the role of energy balance in regulating clock genes. Recent studies have implicated dopamine (DA) to be involved in food entrainment and caloric restriction is known to affect dopaminergic pathways to enhance locomotor activity. Since food entrainment results in the development of a distinct behavioral component, called food anticipatory activity (FAA), we examined the role of locomotor sensitization (LS) in food entrainment by 1) observing whether amphetamine (AMPH) sensitization results in enhanced locomotor output of FAA and 2) measuring LS of circadian and non-circadian feeding paradigms to an acute injection of AMPH (AMPH cross-sensitization). Unexpectedly, AMPH sensitization did not show enhancement of FAA. On the contrary, LS did develop with sufficient exposure to RF. LS was present after 2 weeks of RF, but not after 1, 3 or 7 days into RF. When food was returned and rats regain their original body weight at 10-15 days post-RF, LS remained present. LS did not develop to RT, nor to feedings of a non-circadian schedule, e.g. variable restricted feeding (VRF) or variable RT (VRT). Further, when RF was timed to the dark period, LS was observed only when tested at night; RF timed to the light period resulted in LS that was present during day and night. Taken together our results show that LS develops with food entrainment to RF, an effect that is dependent on the chronicity and circadian phase of RF but independent of body weight. Given that LS involves reorganization of DA-regulated motor circuitry, our work provides indirect support for the role of DA in the food entrainment pathway of RF. The findings also suggest differences in neuronal pathways involved in LS from AMPH sensitization and LS from RF.
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Affiliation(s)
- Hanna Opiol
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC, Canada
| | - Nuria de Zavalia
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC, Canada
| | - Tara Delorme
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC, Canada
| | - Pavel Solis
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC, Canada
| | - Spencer Rutherford
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC, Canada
| | - Uri Shalev
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC, Canada
| | - Shimon Amir
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC, Canada
- * E-mail:
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9
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Cole E, Mistlberger RE, Merza D, Trigiani LJ, Madularu D, Simundic A, Mumby DG. Circadian time-place (or time-route) learning in rats with hippocampal lesions. Neurobiol Learn Mem 2016; 136:236-243. [PMID: 27622983 DOI: 10.1016/j.nlm.2016.09.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 09/02/2016] [Accepted: 09/09/2016] [Indexed: 01/22/2023]
Abstract
Circadian time-place learning (TPL) is the ability to remember both the place and biological time of day that a significant event occurred (e.g., food availability). This ability requires that a circadian clock provide phase information (a time tag) to cognitive systems involved in linking representations of an event with spatial reference memory. To date, it is unclear which neuronal substrates are critical in this process, but one candidate structure is the hippocampus (HPC). The HPC is essential for normal performance on tasks that require allocentric spatial memory and exhibits circadian rhythms of gene expression that are sensitive to meal timing. Using a novel TPL training procedure and enriched, multidimensional environment, we trained rats to locate a food reward that varied between two locations relative to time of day. After rats acquired the task, they received either HPC or SHAM lesions and were re-tested. Rats with HPC lesions were initially impaired on the task relative to SHAM rats, but re-attained high scores with continued testing. Probe tests revealed that the rats were not using an alternation strategy or relying on light-dark transitions to locate the food reward. We hypothesize that transient disruption and recovery reflect a switch from HPC-dependent allocentric navigation (learning places) to dorsal striatum-dependent egocentric spatial navigation (learning routes to a location). Whatever the navigation strategy, these results demonstrate that the HPC is not required for rats to find food in different locations using circadian phase as a discriminative cue.
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Affiliation(s)
- Emily Cole
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC, Canada.
| | | | - Devon Merza
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC, Canada
| | - Lianne J Trigiani
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC, Canada
| | - Dan Madularu
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC, Canada
| | - Amanda Simundic
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC, Canada
| | - Dave G Mumby
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC, Canada
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10
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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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11
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Vaanholt LM, Mitchell SE, Sinclair RE, Speakman JR. Mice that are resistant to diet-induced weight loss have greater food anticipatory activity and altered melanocortin-3 receptor (MC3R) and dopamine receptor 2 (D2) gene expression. Horm Behav 2015; 73:83-93. [PMID: 26122292 DOI: 10.1016/j.yhbeh.2015.06.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 06/12/2015] [Accepted: 06/13/2015] [Indexed: 11/20/2022]
Abstract
Diet-induced weight loss varies considerably between individuals, but the mechanisms driving these individual differences remain largely unknown. Here we investigated whether key neuropeptides involved in the regulation of energy balance or reward systems were differentially expressed in mice that were prone or resistant to caloric restriction (CR) induced weight loss. Mice (n=30 males and n=34 females) were fed 70% of their own baseline ad libitum intake for 25days, after which their brains were collected and expression of various neuropeptides were investigated and compared between the 10 male and 10 female mice that showed the greatest (high weight loss, HWL) or lowest weight loss (LWL) (n=40 in total). HWL mice showed a differential neuropeptide profile to LWL in both sexes, characterised by increased expression of neuropeptide Y (NPY), agouti-related peptide (AgRP), leptin receptor (ObRb), and melanocortin 3 receptor (MC3R) in the arcuate nucleus. No changes in the expression of fat mass and obesity related gene (FTO) or suppressor of cytokine signalling 3 (Socs3) were observed. Levels of dopamine D2 receptor were decreased in the nucleus accumbens in HWL compared to LWL mice. HWL mice showed a stronger increase in food anticipatory activity (FAA) in response to CR than LWL mice. These results indicate that the mice prone to diet-induced weight loss experienced greater hunger, potentially driving their elevated FAA.
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MESH Headings
- Animals
- Anticipation, Psychological/physiology
- Arcuate Nucleus of Hypothalamus/metabolism
- Caloric Restriction
- Diet, Reducing
- Energy Metabolism/genetics
- Female
- Food
- Gene Expression
- Humans
- Male
- Mice
- Mice, Obese
- Neuropeptide Y/genetics
- Neuropeptide Y/metabolism
- Obesity/diet therapy
- Obesity/genetics
- Obesity/metabolism
- Receptor, Melanocortin, Type 3/genetics
- Receptor, Melanocortin, Type 3/metabolism
- Receptors, Dopamine D2/genetics
- Receptors, Dopamine D2/metabolism
- Receptors, Leptin/genetics
- Receptors, Leptin/metabolism
- Treatment Failure
- Weight Loss/genetics
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Affiliation(s)
- Lobke M Vaanholt
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK.
| | - Sharon E Mitchell
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
| | - Rachel E Sinclair
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
| | - John R Speakman
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK; State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
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12
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Patton DF, Katsuyama ÂM, Pavlovski I, Michalik M, Patterson Z, Parfyonov M, Smit AN, Marchant EG, Chung J, Abizaid A, Storch KF, de la Iglesia H, Mistlberger RE. Circadian mechanisms of food anticipatory rhythms in rats fed once or twice daily: clock gene and endocrine correlates. PLoS One 2014; 9:e112451. [PMID: 25502949 PMCID: PMC4263600 DOI: 10.1371/journal.pone.0112451] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 10/07/2014] [Indexed: 12/20/2022] Open
Abstract
Circadian clocks in many brain regions and peripheral tissues are entrained by the daily rhythm of food intake. Clocks in one or more of these locations generate a daily rhythm of locomotor activity that anticipates a regular mealtime. Rats and mice can also anticipate two daily meals. Whether this involves 1 or 2 circadian clocks is unknown. To gain insight into how the circadian system adjusts to 2 daily mealtimes, male rats in a 12∶12 light-dark cycle were fed a 2 h meal either 4 h after lights-on or 4 h after lights-off, or a 1 h meal at both times. After 30 days, brain, blood, adrenal and stomach tissue were collected at 6 time points. Multiple clock genes from adrenals and stomachs were assayed by RT-PCR. Blood was assayed for corticosterone and ghrelin. Bmal1 expression was quantified in 14 brain regions by in situ hybridization. Clock gene rhythms in adrenal and stomach from day-fed rats oscillated in antiphase with the rhythms in night-fed rats, and at an intermediate phase in rats fed twice daily. Corticosterone and ghrelin in 1-meal rats peaked at or prior to the expected mealtime. In 2-meal rats, corticosterone peaked only prior the nighttime meal, while ghrelin peaked prior to the daytime meal and then remained elevated. The olfactory bulb, nucleus accumbens, dorsal striatum, cerebellum and arcuate nucleus exhibited significant daily rhythms of Bmal1 in the night-fed groups that were approximately in antiphase in the day-fed groups, and at intermediate levels (arrhythmic) in rats anticipating 2 daily meals. The dissociations between anticipatory activity and the peripheral clocks and hormones in rats anticipating 2 daily meals argue against a role for these signals in the timing of behavioral rhythms. The absence of rhythmicity at the tissue level in brain regions from rats anticipating 2 daily meals support behavioral evidence that circadian clock cells in these tissues may reorganize into two populations coupled to different meals.
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Affiliation(s)
- Danica F. Patton
- Department of Psychology, Simon Fraser University, Burnaby, BC, Canada
| | - Ângela M. Katsuyama
- Department of Biology, University of Washington, Seattle, WA, United States of America
| | - Ilya Pavlovski
- Department of Psychology, Simon Fraser University, Burnaby, BC, Canada
| | - Mateusz Michalik
- Department of Psychology, Simon Fraser University, Burnaby, BC, Canada
| | | | - Maksim Parfyonov
- Department of Psychology, Simon Fraser University, Burnaby, BC, Canada
| | - Andrea N. Smit
- Department of Psychology, Simon Fraser University, Burnaby, BC, Canada
| | | | - John Chung
- Department of Biology, University of Washington, Seattle, WA, United States of America
| | - Alfonso Abizaid
- Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | | | - Horacio de la Iglesia
- Department of Biology, University of Washington, Seattle, WA, United States of America
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13
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Mendoza J, Challet E. Circadian insights into dopamine mechanisms. Neuroscience 2014; 282:230-42. [PMID: 25281877 DOI: 10.1016/j.neuroscience.2014.07.081] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 07/22/2014] [Accepted: 07/24/2014] [Indexed: 01/11/2023]
Abstract
Almost every physiological or behavioral process in mammals follows rhythmic patterns, which depend mainly on a master circadian clock located in the hypothalamic suprachiasmatic nucleus (SCN). The dopaminergic (DAergic) system in the brain is principally implicated in motor functions, motivation and drug intake. Interestingly, DA-related parameters and behaviors linked to the motivational and arousal states, show daily rhythms that could be regulated by the SCN or by extra-SCN circadian oscillator(s) modulating DAergic systems. Here we examine what is currently understood about the anatomical and functional central multi-oscillatory circadian system, highlighting how the main SCN clock communicates timing information with other brain clocks to regulate the DAergic system and conversely, how DAergic cues may have feedback effects on the SCN. These studies give new insights into the role of the brain circadian system in DA-related neurologic pathologies, such as Parkinson's disease, attention deficit/hyperactive disorder and drug addiction.
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Affiliation(s)
- J Mendoza
- Institute of Cellular and Integrative Neurosciences, CNRS UPR-3212, University of Strasbourg, 5 rue Blaise Pascal, 67084 Strasbourg cedex, France.
| | - E Challet
- Institute of Cellular and Integrative Neurosciences, CNRS UPR-3212, University of Strasbourg, 5 rue Blaise Pascal, 67084 Strasbourg cedex, France
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14
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Gallardo CM, Darvas M, Oviatt M, Chang CH, Michalik M, Huddy TF, Meyer EE, Shuster SA, Aguayo A, Hill EM, Kiani K, Ikpeazu J, Martinez JS, Purpura M, Smit AN, Patton DF, Mistlberger RE, Palmiter RD, Steele AD. Dopamine receptor 1 neurons in the dorsal striatum regulate food anticipatory circadian activity rhythms in mice. eLife 2014; 3:e03781. [PMID: 25217530 PMCID: PMC4196120 DOI: 10.7554/elife.03781] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 09/10/2014] [Indexed: 12/23/2022] Open
Abstract
Daily rhythms of food anticipatory activity (FAA) are regulated independently of the suprachiasmatic nucleus, which mediates entrainment of rhythms to light, but the neural circuits that establish FAA remain elusive. In this study, we show that mice lacking the dopamine D1 receptor (D1R KO mice) manifest greatly reduced FAA, whereas mice lacking the dopamine D2 receptor have normal FAA. To determine where dopamine exerts its effect, we limited expression of dopamine signaling to the dorsal striatum of dopamine-deficient mice; these mice developed FAA. Within the dorsal striatum, the daily rhythm of clock gene period2 expression was markedly suppressed in D1R KO mice. Pharmacological activation of D1R at the same time daily was sufficient to establish anticipatory activity in wild-type mice. These results demonstrate that dopamine signaling to D1R-expressing neurons in the dorsal striatum plays an important role in manifestation of FAA, possibly by synchronizing circadian oscillators that modulate motivational processes and behavioral output.
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Affiliation(s)
- Christian M Gallardo
- Division of Biology, California Institute of Technology, Pasadena, United States
| | - Martin Darvas
- Department of Pathology, University of Washington, Seattle, United States
| | - Mia Oviatt
- Division of Biology, California Institute of Technology, Pasadena, United States
| | - Chris H Chang
- W M Keck Science Department, Claremont McKenna, Pitzer and Scripps Colleges, Claremont, United States
| | - Mateusz Michalik
- Department of Psychology, Simon Fraser University, Burnaby, Canada
| | - Timothy F Huddy
- Biological Sciences Department, California State Polytechnic University Pomona, Pomona, United States
| | - Emily E Meyer
- W M Keck Science Department, Claremont McKenna, Pitzer and Scripps Colleges, Claremont, United States
| | - Scott A Shuster
- Division of Biology, California Institute of Technology, Pasadena, United States
| | - Antonio Aguayo
- Biological Sciences Department, California State Polytechnic University Pomona, Pomona, United States
| | - Elizabeth M Hill
- Biological Sciences Department, California State Polytechnic University Pomona, Pomona, United States
| | - Karun Kiani
- W M Keck Science Department, Claremont McKenna, Pitzer and Scripps Colleges, Claremont, United States
| | - Jonathan Ikpeazu
- Division of Biology, California Institute of Technology, Pasadena, United States
| | - Johan S Martinez
- Division of Biology, California Institute of Technology, Pasadena, United States
| | - Mari Purpura
- W M Keck Science Department, Claremont McKenna, Pitzer and Scripps Colleges, Claremont, United States
| | - Andrea N Smit
- Department of Psychology, Simon Fraser University, Burnaby, Canada
| | - Danica F Patton
- Department of Psychology, Simon Fraser University, Burnaby, Canada
| | | | - Richard D Palmiter
- Department of Biochemistry, Howard Hughes Medical Institute, University of Washington, Seattle, United States
| | - Andrew D Steele
- Division of Biology, California Institute of Technology, Pasadena, United States
- Biological Sciences Department, California State Polytechnic University Pomona, Pomona, United States
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15
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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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16
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Smit AN, Patton DF, Michalik M, Opiol H, Mistlberger RE. Dopaminergic regulation of circadian food anticipatory activity rhythms in the rat. PLoS One 2013; 8:e82381. [PMID: 24312417 PMCID: PMC3843722 DOI: 10.1371/journal.pone.0082381] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 10/25/2013] [Indexed: 11/23/2022] Open
Abstract
Circadian activity rhythms are jointly controlled by a master pacemaker in the hypothalamic suprachiasmatic nuclei (SCN) and by food-entrainable circadian oscillators (FEOs) located elsewhere. The SCN mediates synchrony to daily light-dark cycles, whereas FEOs generate activity rhythms synchronized with regular daily mealtimes. The location of FEOs generating food anticipation rhythms, and the pathways that entrain these FEOs, remain to be clarified. To gain insight into entrainment pathways, we developed a protocol for measuring phase shifts of anticipatory activity rhythms in response to pharmacological probes. We used this protocol to examine a role for dopamine signaling in the timing of circadian food anticipation. To generate a stable food anticipation rhythm, rats were fed 3h/day beginning 6-h after lights-on or in constant light for at least 3 weeks. Rats then received the D2 agonist quinpirole (1 mg/kg IP) alone or after pretreatment with the dopamine synthesis inhibitor α-methylparatyrosine (AMPT). By comparison with vehicle injections, quinpirole administered 1-h before lights-off (19h before mealtime) induced a phase delay of activity onset prior to the next meal. Delay shifts were larger in rats pretreated with AMPT, and smaller following quinpirole administered 4-h after lights-on. A significant shift was not observed in response to the D1 agonist SKF81297. These results provide evidence that signaling at D2 receptors is involved in phase control of FEOs responsible for circadian food anticipatory rhythms in rats.
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Affiliation(s)
- Andrea N. Smit
- Department of Psychology, Simon Fraser University, Burnaby, BC, Canada
| | - Danica F. Patton
- Department of Psychology, Simon Fraser University, Burnaby, BC, Canada
| | - Mateusz Michalik
- Department of Psychology, Simon Fraser University, Burnaby, BC, Canada
| | - Hanna Opiol
- Department of Psychology, Simon Fraser University, Burnaby, BC, Canada
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17
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Circadian aspects of energy metabolism and aging. Ageing Res Rev 2013; 12:931-40. [PMID: 24075855 DOI: 10.1016/j.arr.2013.09.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Revised: 09/10/2013] [Accepted: 09/17/2013] [Indexed: 11/24/2022]
Abstract
Life span extension has been a goal of research for several decades. Resetting circadian rhythms leads to well being and increased life span, while clock disruption is associated with increased morbidity accelerated aging. Increased longevity and improved health can be achieved by different feeding regimens that reset circadian rhythms and may lead to better synchrony in metabolism and physiology. This review focuses on the circadian aspects of energy metabolism and their relationship with aging in mammals.
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18
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Principles of motivation revealed by the diverse functions of neuropharmacological and neuroanatomical substrates underlying feeding behavior. Neurosci Biobehav Rev 2013; 37:1985-98. [PMID: 23466532 DOI: 10.1016/j.neubiorev.2013.02.017] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Revised: 02/12/2013] [Accepted: 02/22/2013] [Indexed: 11/21/2022]
Abstract
Circuits that participate in specific subcomponents of feeding (e.g., gustatory perception, peripheral feedback relevant to satiety and energy balance, reward coding, etc.) are found at all levels of the neural axis. Further complexity is conferred by the wide variety of feeding-modulatory neurotransmitters and neuropeptides that act within these circuits. An ongoing challenge has been to refine the understanding of the functional specificity of these neurotransmitters and circuits, and there have been exciting advances in recent years. We focus here on foundational work of Dr. Ann Kelley that identified distinguishable actions of striatal opioid peptide modulation and dopamine transmission in subcomponents of reward processing. We also discuss her work in overlaying these neuropharmacological effects upon anatomical pathways that link the telencephalon (cortex and basal ganglia) with feeding-control circuits in the hypothalamus. Using these seminal contributions as a starting point, we will discuss new findings that expand our understanding of (1) the specific, differentiable motivational processes that are governed by central dopamine and opioid transmission, (2) the manner in which other striatal neuromodulators, specifically acetylcholine, endocannabinoids and adenosine, modulate these motivational processes (including via interactions with opioid systems), and (3) the organization of the cortical-subcortical network that subserves opioid-driven feeding. The findings discussed here strengthen the view that incentive-motivational properties of food are coded by substrates and neural circuits that are distinguishable from those that mediate the acute hedonic experience of food reward. Striatal opioid transmission modulates reward processing by engaging frontotemporal circuits, possibly via a hypothalamic-thalamic axis, that ultimately impinges upon hypothalamic modules dedicated to autonomic function and motor pattern control. We will conclude by discussing implications for understanding disorders of "non-homeostatic" feeding.
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19
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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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20
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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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21
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Froy O. Circadian rhythms and obesity in mammals. ISRN OBESITY 2012; 2012:437198. [PMID: 24527263 PMCID: PMC3914271 DOI: 10.5402/2012/437198] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 11/11/2012] [Indexed: 02/02/2023]
Abstract
Obesity has become a serious public health problem and a major risk factor for the development of illnesses, such as insulin resistance and hypertension. Attempts to understand the causes of obesity and develop new therapeutic strategies have mostly focused on caloric intake and energy expenditure. Recent studies have shown that the circadian clock controls energy homeostasis by regulating the circadian expression and/or activity of enzymes, hormones, and transport systems involved in metabolism. Moreover, disruption of circadian rhythms leads to obesity and metabolic disorders. Therefore, it is plausible that resetting of the circadian clock can be used as a new approach to attenuate obesity. Feeding regimens, such as restricted feeding (RF), calorie restriction (CR), and intermittent fasting (IF), provide a time cue and reset the circadian clock and lead to better health. In contrast, high-fat (HF) diet leads to disrupted circadian expression of metabolic factors and obesity. This paper focuses on circadian rhythms and their link to obesity.
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Affiliation(s)
- Oren Froy
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, 76100 Rehovot, Israel
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22
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Scheduled daily mating induces circadian anticipatory activity rhythms in the male rat. PLoS One 2012; 7:e40895. [PMID: 22848408 PMCID: PMC3405034 DOI: 10.1371/journal.pone.0040895] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 06/14/2012] [Indexed: 11/28/2022] Open
Abstract
Daily schedules of limited access to food, palatable high calorie snacks, water and salt can induce circadian rhythms of anticipatory locomotor activity in rats and mice. All of these stimuli are rewarding, but whether anticipation can be induced by neural correlates of reward independent of metabolic perturbations associated with manipulations of food and hydration is unclear. Three experiments were conducted to determine whether mating, a non-ingestive behavior that is potently rewarding, can induce circadian anticipatory activity rhythms in male rats provided scheduled daily access to steroid-primed estrous female rats. In Experiment 1, rats anticipated access to estrous females in the mid-light period, but also exhibited post-coital eating and running. In Experiment 2, post-coital eating and running were prevented and only a minority of rats exhibited anticipation. Rats allowed to see and smell estrous females showed no anticipation. In both experiments, all rats exhibited sustained behavioral arousal and multiple mounts and intromissions during every session, but ejaculated only every 2–3 days. In Experiment 3, the rats were given more time with individual females, late at night for 28 days, and then in the midday for 28 days. Ejaculation rates increased and anticipation was robust to night sessions and significant although weaker to day sessions. The anticipation rhythm persisted during 3 days of constant dark without mating. During anticipation of nocturnal mating, the rats exhibited a significant preference for a tube to the mating cage over a tube to a locked cage with mating cage litter. This apparent place preference was absent during anticipation of midday mating, which may reflect a daily rhythm of sexual reward. The results establish mating as a reward stimulus capable of inducing circadian rhythms of anticipatory behavior in the male rat, and reveal a critical role for ejaculation, a modulatory role for time of day, and a potential confound role for uncontrolled food intake.
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Gallardo CM, Gunapala KM, King OD, Steele AD. Daily scheduled high fat meals moderately entrain behavioral anticipatory activity, body temperature, and hypothalamic c-Fos activation. PLoS One 2012; 7:e41161. [PMID: 22815954 PMCID: PMC3397999 DOI: 10.1371/journal.pone.0041161] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Accepted: 06/18/2012] [Indexed: 11/19/2022] Open
Abstract
When fed in restricted amounts, rodents show robust activity in the hours preceding expected meal delivery. This process, termed food anticipatory activity (FAA), is independent of the light-entrained clock, the suprachiasmatic nucleus, yet beyond this basic observation there is little agreement on the neuronal underpinnings of FAA. One complication in studying FAA using a calorie restriction model is that much of the brain is activated in response to this strong hunger signal. Thus, daily timed access to palatable meals in the presence of continuous access to standard chow has been employed as a model to study FAA in rats. In order to exploit the extensive genetic resources available in the murine system we extended this model to mice, which will anticipate rodent high fat diet but not chocolate or other sweet daily meals (Hsu, Patton, Mistlberger, and Steele; 2010, PLoS ONE e12903). In this study we test additional fatty meals, including peanut butter and cheese, both of which induced modest FAA. Measurement of core body temperature revealed a moderate preprandial increase in temperature in mice fed high fat diet but entrainment due to handling complicated interpretation of these results. Finally, we examined activation patterns of neurons by immunostaining for the immediate early gene c-Fos and observed a modest amount of entrainment of gene expression in the hypothalamus of mice fed a daily fatty palatable meal.
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Affiliation(s)
- Christian M. Gallardo
- 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
| | - Oliver D. King
- Boston Biomedical Research Institute, Watertown, Massachusetts, United States of America
| | - Andrew D. Steele
- Division of Biology, California Institute of Technology, Pasadena, California, United States of America
- * E-mail:
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24
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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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25
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Jansen HT, Sergeeva A, Stark G, Sorg BA. Circadian discrimination of reward: evidence for simultaneous yet separable food- and drug-entrained rhythms in the rat. Chronobiol Int 2012; 29:454-68. [PMID: 22475541 DOI: 10.3109/07420528.2012.667467] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A unique extra-suprachiasmatic nucleus (SCN) oscillator, operating independently of the light-entrainable oscillator, has been hypothesized to generate feeding and drug-related rhythms. To test the validity of this hypothesis, sham-lesioned (Sham) and SCN-lesioned (SCNx) rats were housed in constant dim-red illumination (LL(red)) and received a daily cocaine injection every 24 h for 7 d (Experiment 1). In a second experiment, rats underwent 3-h daily restricted feeding (RF) followed 12 d later by the addition of daily cocaine injections given every 25 h in combination with RF until the two schedules were in antiphase. In both experiments, body temperature and total activity were monitored continuously. Results from Experiment 1 revealed that cocaine, but not saline, injections produced anticipatory increases in temperature and activity in SCNx and Sham rats. Following withdrawal from cocaine, free-running temperature rhythms persisted for 2-10 d in SCNx rats. In Experiment 2, robust anticipatory increases in temperature and activity were associated with RF and cocaine injections; however, the feeding periodicity (23.9 h) predominated over the cocaine periodicity. During drug withdrawal, the authors observed two free-running rhythms of temperature and activity that persisted for >14 d in both Sham and SCNx rats. The periods of the free-running rhythms were similar to the feeding entrainment (period = 23.7 and 24.0 h, respectively) and drug entrainment (period = 25.7 and 26.1 h, respectively). Also during withdrawal, the normally close correlation between activity and temperature was greatly disrupted in Sham and SCNx rats. Taken together, these results do not support the existence of a single oscillator mediating the rewarding properties of both food and cocaine. Rather, they suggest that these two highly rewarding behaviors can be temporally isolated, especially during drug withdrawal. Under stable dual-entrainment conditions, food reward appears to exhibit a slightly greater circadian influence than drug reward. The ability to generate free-running temperature rhythms of different frequencies following combined food and drug exposures could reflect a state of internal desynchrony that may contribute to the addiction process and drug relapse.
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Affiliation(s)
- Heiko T Jansen
- Neuroscience Program, Department of Veterinary and Comparative Anatomy, Pharmacology, and Physiology, Washington State University, Pullman, 99164-6520, USA.
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26
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Abstract
Resetting the circadian clock leads to well being and increased life span, whereas clock disruption is associated with aging and morbidity. Increased longevity and improved health can be achieved by different feeding regimens that reset circadian rhythms and may lead to better synchrony in metabolism and physiology. This review focuses on recent findings concerning the relationships between circadian rhythms, aging attenuation, and life-span extension in mammals.
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Affiliation(s)
- Oren Froy
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel.
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27
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Sherman H, Frumin I, Gutman R, Chapnik N, Lorentz A, Meylan J, le Coutre J, Froy O. Long-term restricted feeding alters circadian expression and reduces the level of inflammatory and disease markers. J Cell Mol Med 2011; 15:2745-59. [PMID: 20731750 PMCID: PMC4373423 DOI: 10.1111/j.1582-4934.2010.01160.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Accepted: 07/20/2010] [Indexed: 12/22/2022] Open
Abstract
The circadian clock in peripheral tissues can be entrained by restricted feeding (RF), a regimen that restricts the duration of food availability with no calorie restriction (CR). However, it is not known whether RF can delay the occurrence of age-associated changes similar to CR. We measured circadian expression of clock genes, disease marker genes, metabolic factors and inflammatory and allergy markers in mouse serum, liver, jejunum and white adipose tissue (WAT) after long-term RF of 4 months. We found that circadian rhythmicity is more robust and is phase advanced in most of the genes and proteins tested under RF. In addition, average daily levels of some disease and inflammatory markers were reduced under RF, including liver Il-6 mRNA, tumour necrosis factor (TNF)-α and nuclear factor κB (NF-κB) protein; jejunum Arginase, Afp, Gadd45β, Il-1α and Il-1β mRNA, and interleukin (IL)-6 and TNF-α protein and WAT Il-6, Il-1β, Tnfα and Nfκb mRNA. In contrast, the anti-inflammatory cytokine Il-10 mRNA increased in the liver and jejunum. Our results suggest that RF may share some benefits with those of CR. As RF is a less harsh regimen to follow than CR, the data suggest it could be proposed for individuals seeking to improve their health.
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Affiliation(s)
- Hadas Sherman
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of JerusalemRehovot, Israel
| | - Idan Frumin
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of JerusalemRehovot, Israel
| | - Roee Gutman
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of JerusalemRehovot, Israel
| | - Nava Chapnik
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of JerusalemRehovot, Israel
| | - Axel Lorentz
- Department of Nutritional Medicine, University of HohenheimStuttgart, Germany
| | - Jenny Meylan
- Nestlé Research CenterVers-chez-les-Blanc, Lausanne, Switzerland
| | - Johannes le Coutre
- Nestlé Research CenterVers-chez-les-Blanc, Lausanne, Switzerland
- The University of Tokyo, Organization for Interdisciplinary Research ProjectsYayoi, Bunkyo-ku, Tokyo, Japan
| | - Oren Froy
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of JerusalemRehovot, Israel
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28
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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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29
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Khan ZU, Martín-Montañez E, Baxter MG. Visual perception and memory systems: from cortex to medial temporal lobe. Cell Mol Life Sci 2011; 68:1737-54. [PMID: 21365279 PMCID: PMC11115075 DOI: 10.1007/s00018-011-0641-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Revised: 01/31/2011] [Accepted: 02/15/2011] [Indexed: 10/18/2022]
Abstract
Visual perception and memory are the most important components of vision processing in the brain. It was thought that the perceptual aspect of a visual stimulus occurs in visual cortical areas and that this serves as the substrate for the formation of visual memory in a distinct part of the brain called the medial temporal lobe. However, current evidence indicates that there is no functional separation of areas. Entire visual cortical pathways and connecting medial temporal lobe are important for both perception and visual memory. Though some aspects of this view are debated, evidence from both sides will be explored here. In this review, we will discuss the anatomical and functional architecture of the entire system and the implications of these structures in visual perception and memory.
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Affiliation(s)
- Zafar U Khan
- Laboratory of Neurobiology, CIMES, Facultad de Medicina, University of Malaga, 29071, Malaga, Spain.
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30
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Mistlberger RE. Neurobiology of food anticipatory circadian rhythms. Physiol Behav 2011; 104:535-45. [PMID: 21527266 DOI: 10.1016/j.physbeh.2011.04.015] [Citation(s) in RCA: 220] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 04/13/2011] [Accepted: 04/13/2011] [Indexed: 12/29/2022]
Abstract
Circadian rhythms in mammals can be entrained by daily schedules of light or food availability. A master light-entrainable circadian pacemaker located in the suprachiasmatic nucleus (SCN) is comprised of a population of cell autonomous, transcriptionally based circadian oscillators with defined retinal inputs, circadian clock genes and neural outputs. By contrast, the neurobiology of food-entrainable circadian rhythmicity remains poorly understood at the systems and cellular levels. Induction of food-anticipatory activity rhythms by daily feeding schedules does not require the SCN, but these rhythms do exhibit defining properties of circadian clock control. Clock gene rhythms expressed in other brain regions and in peripheral organs are preferentially reset by mealtime, but lesions of specific hypothalamic, corticolimbic and brainstem structures do not eliminate all food anticipatory rhythms, suggesting control by a distributed, decentralized system of oscillators, or the existence of a critical oscillator at an unknown location. The melanocortin system and dorsomedial hypothalamus may play modulatory roles setting the level of anticipatory activity. The metabolic hormones ghrelin and leptin are not required to induce behavioral food anticipatory rhythms, but may also participate in gain setting. Clock gene mutations that disrupt light-entrainable rhythms generally do not eliminate food anticipatory rhythms, suggesting a novel timing mechanism. Recent evidence for non-transcriptional and network based circadian rhythmicity provides precedence, but any such mechanisms are likely to interact closely with known circadian clock genes, and some important double and triple clock gene knockouts remain to be phenotyped for food entrainment. Given the dominant role of food as an entraining stimulus for metabolic rhythms, the timing of daily food intake and the fidelity of food entrainment mechanisms are likely to have clinical relevance.
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Affiliation(s)
- Ralph E Mistlberger
- Department of Psychology, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada.
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31
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Froy O, Miskin R. Effect of feeding regimens on circadian rhythms: implications for aging and longevity. Aging (Albany NY) 2010; 2:7-27. [PMID: 20228939 PMCID: PMC2837202 DOI: 10.18632/aging.100116] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2009] [Accepted: 01/09/2010] [Indexed: 01/19/2023]
Abstract
Increased longevity and improved health can be achieved in mammals by two feeding regimens, caloric restriction (CR), which limits the amount of daily calorie intake, and intermittent fasting (IF), which allows the food to be available ad libitum every other day. The precise mechanisms mediating these beneficial effects are still unresolved. Resetting the circadian clock is another intervention that can lead to increased life span and well being, while clock disruption is associated with aging and morbidity. Currently, a large body of evidence links circadian rhythms with metabolism and feeding regimens. In particular, CR, and possibly also IF, can entrain the master clock located in the suprachiasmatic nuclei (SCN) of the brain hypothalamus. These findings raise the hypothesis that the beneficial effects exerted by these feeding regimens could be mediated, at least in part, through resetting of the circadian clock, thus leading to synchrony in metabolism and physiology. This hypothesis is reinforced by a transgenic mouse model showing spontaneously reduced eating alongside robust circadian rhythms and increased life span. This review will summarize recent findings concerning the relationships between feeding regimens, circadian rhythms, and metabolism with implications for ageing attenuation and life span extension.
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Affiliation(s)
- Oren Froy
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
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32
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Hsu CT, Patton DF, Mistlberger RE, Steele AD. Palatable meal anticipation in mice. PLoS One 2010; 5. [PMID: 20941366 PMCID: PMC2948008 DOI: 10.1371/journal.pone.0012903] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2010] [Accepted: 08/25/2010] [Indexed: 01/10/2023] Open
Abstract
The ability to sense time and anticipate events is a critical skill in nature. Most efforts to understand the neural and molecular mechanisms of anticipatory behavior in rodents rely on daily restricted food access, which induces a robust increase of locomotor activity in anticipation of daily meal time. Interestingly, rats also show increased activity in anticipation of a daily palatable meal even when they have an ample food supply, suggesting a role for brain reward systems in anticipatory behavior, and providing an alternate model by which to study the neurobiology of anticipation in species, such as mice, that are less well adapted to “stuff and starve” feeding schedules. To extend this model to mice, and exploit molecular genetic resources available for that species, we tested the ability of wild-type mice to anticipate a daily palatable meal. We observed that mice with free access to regular chow and limited access to highly palatable snacks of chocolate or “Fruit Crunchies” avidly consumed the snack but did not show anticipatory locomotor activity as measured by running wheels or video-based behavioral analysis. However, male mice receiving a snack of high fat chow did show increased food bin entry prior to access time and a modest increase in activity in the two hours preceding the scheduled meal. Interestingly, female mice did not show anticipation of a daily high fat meal but did show increased activity at scheduled mealtime when that meal was withdrawn. These results indicate that anticipation of a scheduled food reward in mice is behavior, diet, and gender specific.
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Affiliation(s)
- Cynthia T. Hsu
- Broad Fellows Program in Brain Circuitry, Division of Biology, California Institute of Technology, Pasadena, California, United States of America
| | - Danica F. Patton
- Department of Psychology, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Ralph E. Mistlberger
- Department of Psychology, Simon Fraser University, Burnaby, British Columbia, Canada
- * E-mail: (ADS); (REM)
| | - Andrew D. Steele
- Broad Fellows Program in Brain Circuitry, Division of Biology, California Institute of Technology, Pasadena, California, United States of America
- * E-mail: (ADS); (REM)
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33
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Hsu JL, Yu L, Sullivan E, Bowman M, Mistlberger RE, Tecott LH. Enhanced food anticipatory activity associated with enhanced activation of extrahypothalamic neural pathways in serotonin2C receptor null mutant mice. PLoS One 2010; 5:e11802. [PMID: 20668550 PMCID: PMC2910710 DOI: 10.1371/journal.pone.0011802] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2010] [Accepted: 05/21/2010] [Indexed: 11/19/2022] Open
Abstract
The ability to entrain circadian rhythms to food availability is important for survival. Food-entrained circadian rhythms are characterized by increased locomotor activity in anticipation of food availability (food anticipatory activity). However, the molecular components and neural circuitry underlying the regulation of food anticipatory activity remain unclear. Here we show that serotonin(2C) receptor (5-HT2CR) null mutant mice subjected to a daytime restricted feeding schedule exhibit enhanced food anticipatory activity compared to wild-type littermates, without phenotypic differences in the impact of restricted feeding on food consumption, body weight loss, or blood glucose levels. Moreover, we show that the enhanced food anticipatory activity in 5-HT2CR null mutant mice develops independent of external light cues and persists during two days of total food deprivation, indicating that food anticipatory activity in 5-HT2CR null mutant mice reflects the locomotor output of a food-entrainable oscillator. Whereas restricted feeding induces c-fos expression to a similar extent in hypothalamic nuclei of wild-type and null mutant animals, it produces enhanced expression in the nucleus accumbens and other extrahypothalamic regions of null mutant mice relative to wild-type subjects. These data suggest that 5-HT2CRs gate food anticipatory activity through mechanisms involving extrahypothalamic neural pathways.
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Affiliation(s)
- Jennifer L Hsu
- Gladstone Institute of Neurological Disease, San Francisco, California, United States of America
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34
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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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35
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Scheurink AJW, Boersma GJ, Nergårdh R, Södersten P. Neurobiology of hyperactivity and reward: agreeable restlessness in anorexia nervosa. Physiol Behav 2010; 100:490-5. [PMID: 20361989 DOI: 10.1016/j.physbeh.2010.03.016] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Accepted: 03/18/2010] [Indexed: 11/18/2022]
Abstract
Restricted food intake is associated with increased physical activity, very likely an evolutionary advantage, initially both functional and rewarding. The hyperactivity of patients with anorexia nervosa, however, is a main problem for recovery. This seemingly paradoxical reward of hyperactivity in anorexia nervosa is one of the main aspects in our framework for the neurobiological changes that may underlie the development of the disorder. Here, we focus on the neurobiological basis of hyperactivity and reward in both animals and humans suggesting that the mesolimbic dopamine and hypothalamic orexin neurons play central roles. The paper represents an invited review by a symposium, award winner or keynote speaker at the Society for the Study of Ingestive Behavior [SSIB] Annual Meeting in Portland, July 2009.
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36
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Dibner C, Schibler U, Albrecht U. The Mammalian Circadian Timing System: Organization and Coordination of Central and Peripheral Clocks. Annu Rev Physiol 2010; 72:517-49. [DOI: 10.1146/annurev-physiol-021909-135821] [Citation(s) in RCA: 1626] [Impact Index Per Article: 116.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Most physiology and behavior of mammalian organisms follow daily oscillations. These rhythmic processes are governed by environmental cues (e.g., fluctuations in light intensity and temperature), an internal circadian timing system, and the interaction between this timekeeping system and environmental signals. In mammals, the circadian timekeeping system has a complex architecture, composed of a central pacemaker in the brain's suprachiasmatic nuclei (SCN) and subsidiary clocks in nearly every body cell. The central clock is synchronized to geophysical time mainly via photic cues perceived by the retina and transmitted by electrical signals to SCN neurons. In turn, the SCN influences circadian physiology and behavior via neuronal and humoral cues and via the synchronization of local oscillators that are operative in the cells of most organs and tissues. Thus, some of the SCN output pathways serve as input pathways for peripheral tissues. Here we discuss knowledge acquired during the past few years on the complex structure and function of the mammalian circadian timing system.
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Affiliation(s)
- Charna Dibner
- Division of Endocrinology, Diabetes and Nutrition, Geneva University Hospital (HUG), CH-1211 Geneva-14, Switzerland
| | - Ueli Schibler
- Department of Molecular Biology & NCCR Frontiers in Genetics, Sciences III, University of Geneva, CH-1211 Geneva-4, Switzerland
| | - Urs Albrecht
- Department of Medicine, Division of Biochemistry, University of Fribourg, CH-1700 Fribourg, Switzerland
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37
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Mendoza J, Clesse D, Pévet P, Challet E. Food-reward signalling in the suprachiasmatic clock. J Neurochem 2010; 112:1489-99. [DOI: 10.1111/j.1471-4159.2010.06570.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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38
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Abstract
Obesity has become a serious public health problem and a major risk factor for the development of illnesses, such as insulin resistance and hypertension. Human homeostatic systems have adapted to daily changes in light and dark in a way that the body anticipates the sleep and activity periods. Mammals have developed an endogenous circadian clock located in the suprachiasmatic nuclei of the anterior hypothalamus that responds to the environmental light-dark cycle. Similar clocks have been found in peripheral tissues, such as the liver, intestine, and adipose tissue, regulating cellular and physiological functions. The circadian clock has been reported to regulate metabolism and energy homeostasis in the liver and other peripheral tissues. This is achieved by mediating the expression and/or activity of certain metabolic enzymes and transport systems. In return, key metabolic enzymes and transcription activators interact with and affect the core clock mechanism. In addition, the core clock mechanism has been shown to be linked with lipogenic and adipogenic pathways. Animals with mutations in clock genes that disrupt cellular rhythmicity have provided evidence for the relationship between the circadian clock and metabolic homeostasis. In addition, clinical studies in shift workers and obese patients accentuate the link between the circadian clock and metabolism. This review will focus on the interconnection between the circadian clock and metabolism, with implications for obesity and how the circadian clock is influenced by hormones, nutrients, and timed meals.
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Affiliation(s)
- Oren Froy
- Institute of Biochemistry, Food Science, and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel.
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39
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Szentirmai E, Kapás L, Sun Y, Smith RG, Krueger JM. Restricted feeding-induced sleep, activity, and body temperature changes in normal and preproghrelin-deficient mice. Am J Physiol Regul Integr Comp Physiol 2009; 298:R467-77. [PMID: 19939974 DOI: 10.1152/ajpregu.00557.2009] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Behavioral and physiological rhythms can be entrained by daily restricted feeding (RF), indicating the existence of a food-entrainable oscillator (FEO). One manifestation of the presence of FEO is anticipatory activity to regularly scheduled feeding. In the present study, we tested if intact ghrelin signaling is required for FEO function by studying food anticipatory activity (FAA) in preproghrelin knockout (KO) and wild-type (WT) mice. Sleep-wake activity, locomotor activity, body temperature, food intake, and body weight were measured for 12 days in mice on a RF paradigm with food available only for 4 h daily during the light phase. On RF days 1-3, increases in arousal occurred. This response was significantly attenuated in preproghrelin KO mice. There were progressive changes in sleep architecture and body temperature during the subsequent nine RF days. Sleep increased at night and decreased during the light periods while the total daily amount of sleep remained at baseline levels in both KO and WT mice. Body temperature fell during the dark but was elevated during and after feeding in the light. In the premeal hours, anticipatory increases in body temperature, locomotor activity, and wakefulness were present from RF day 6 in both groups. Results indicate that the preproghrelin gene is not required for the manifestation of FAA but suggest a role for ghrelinergic mechanisms in food deprivation-induced arousal in mice.
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Affiliation(s)
- Eva Szentirmai
- WWAMI Medical Education Program, Washington State Univ., Spokane, P.O. Box 1495, Spokane, WA 99210-1495, USA.
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40
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Webb IC, Baltazar RM, Lehman MN, Coolen LM. Bidirectional interactions between the circadian and reward systems: is restricted food access a unique zeitgeber? Eur J Neurosci 2009; 30:1739-48. [PMID: 19878278 DOI: 10.1111/j.1460-9568.2009.06966.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Reward is mediated by a distributed series of midbrain and basal forebrain structures collectively referred to as the brain reward system. Recent evidence indicates that an additional regulatory system, the circadian system, can modulate reward-related learning. Diurnal or circadian changes in drug self-administration, responsiveness to drugs of abuse and reward to natural stimuli have been reported. These variations are associated with daily rhythms in mesolimbic electrical activity, dopamine synthesis and metabolism, and local clock gene oscillations. Conversely, the presentation of rewards appears capable of influencing circadian timing. Rodents can anticipate a daily mealtime by the entrainment of a series of oscillators that are anatomically distinct from the suprachiasmatic nucleus. Other work has indicated that restricted access to non-nutritive reinforcers (e.g. drugs of abuse, sex) or to palatable food in the absence of an energy deficit is capable of inducing relatively weak anticipatory activity, suggesting that reward alone is sufficient to induce anticipation. Recent attempts to elucidate the neural correlates of anticipation have revealed that both restricted feeding and restricted palatable food access can entrain clock gene expression in many reward-related corticolimbic structures. By contrast, restricted feeding alone can induce or entrain clock gene expression in hypothalamic nuclei involved in energy homeostasis. Thus, under ad libitum feeding conditions, the weak anticipatory activity induced by restricted reward presentation may result from the entrainment of reward-associated corticolimbic structures. The additional induction or entrainment of oscillators in hypothalamic regulatory areas may contribute to the more robust anticipatory activity associated with restricted feeding schedules.
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Affiliation(s)
- Ian C Webb
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 5C1, Canada
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41
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Abstract
The circadian system in mammals consists of the central clock in the hypothalamic suprachiasmatic nucleus (SCN) and the peripheral clocks in a variety of tissues and organs. The SCN clock entrains to a light-dark cycle and resets the peripheral clocks. In addition, there are at least two other clocks in the circadian domain which are independent of the SCN and which entrain to nonphotic time cues: methamphetamine (MAP)-induced and restricted daily feeding (RF)-induced clocks. Neither the site nor the mechanism of SCN-independent clocks is known. Canonical clock genes for circadian oscillation are not required for the expression of either SCN-independent rhythm. The central catecholaminergic system is probably involved in the expression of the SCN-independent rhythms, especially of the MAP-induced rhythm. MAP-induced activity rhythms in rats and the sleep-wake cycles in humans share unique phenomena such as spontaneous internal desynchronization, circabidian rhythm and nonphotic entrainment, suggesting overlapping oscillatory mechanisms. The SCN-independent clock is an adaptation that regulates behavior in response to nonphotic time cues, and seems to be closely related to the arousal mechanism.
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Affiliation(s)
- Ken-ichi Honma
- Department of Physiology, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan.
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42
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Abstract
Behavior ablation remains a powerful, if not cutting-edge, approach for localization of function within the nervous system. The initial discovery of the suprachiasmatic nuclei as the site of the mammalian light-entrainable circadian pacemaker is owed to this approach. Food-anticipatory activity (FAA), an output of a putative feeding-entrainable circadian pacemaker, is a behavior that has been surprisingly resilient to elimination by surgical lesion. Here we review this literature, with particular attention paid to recent studies aimed at defining the role of the dorsomedial hypothalamus in the generation of FAA. This literature is fraught with examples of inconsistent results among lesion studies, which in some cases can be accounted for by varied endpoint measures. The site of the feeding-entrainable circadian pacemaker, if it resides in a discrete structure at all, remains unknown.
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Affiliation(s)
- Alec J Davidson
- Circadian Rhythms and Sleep Disorders Program, Department of Neurobiology, Morehouse School of Medicine, 720 Westview Dr., SW, Atlanta, GA 30310, USA.
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43
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Abstract
An essential component of energy homeostasis lies in an organism's ability to coordinate daily patterns in activity, feeding, energy utilization and energy storage across the daily 24-h cycle. Most tissues of the body contain the molecular clock machinery required for circadian oscillation and rhythmic gene expression. Under normal circumstances, behavioural and physiological rhythms are orchestrated and synchronized by the suprachiasmatic nucleus (SCN) of the hypothalamus, considered to be the master circadian clock. However, metabolic processes are easily decoupled from the primarily light-driven SCN when food intake is desynchronized from normal diurnal patterns of activity. This dissociation from SCN based timing demonstrates that the circadian system is responsive to changes in energy supply and metabolic status. There has long been evidence for the existence of an anatomically distinct and autonomous food-entrainable oscillator (FEO) that can govern behavioural rhythms, when feeding becomes the dominant entraining stimulus. But now rapidly growing evidence suggests that core circadian clock genes are involved in reciprocal transcriptional feedback with genetic regulators of metabolism, and are directly responsive to cellular energy supply. This close interaction is likely to be critical for normal circadian regulation of metabolism, and may also underlie the disruption of proper metabolic rhythms observed in metabolic disorders, such as obesity and type-II diabetes.
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44
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Duclos M, Gatti C, Bessière B, Mormède P. Tonic and phasic effects of corticosterone on food restriction-induced hyperactivity in rats. Psychoneuroendocrinology 2009; 34:436-45. [PMID: 19028018 DOI: 10.1016/j.psyneuen.2008.10.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Revised: 10/07/2008] [Accepted: 10/12/2008] [Indexed: 11/16/2022]
Abstract
In the experimental rat model of anorexia nervosa the interactions between the hyperactivity of the hypothalamo-pituitary-adrenal (HPA) axis and increased physical activity associated with food restriction remain unidentified. In addition to their role in energy homeostasis, glucocorticoids have complex effects in the central nervous system, increasing the salience of activities such as wheel running. The objective of the present study was to analyze the role of corticosterone (cort) on wheel activity in food-restricted rats. Lewis rats were adrenalectomized and replaced with pellets containing increasing amounts of cort that caused different steady-state plasma concentrations from low to high HPA activity. They were given free access to a running wheel and were fed ad libitum or food-restricted. We also investigated the acute effect of cort injection mimicking the prefeeding cort peak on prefeeding wheel activity. Wheel running induced by food restriction was nearly non-existent in adrenalectomized food-restricted rats and increased in a dose-related manner with cort replacement. An acute stimulation of activity was also expressed during the preprandial peak of cort, suppressed by adrenalectomy and experimentally restored by acute cort injection. No such effects of cort were found in ad libitum fed rats. Our data demonstrate that food restriction-induced hyperactivity is critically and quantitatively dependent upon cort, not only on the mean basal levels of the hormone but also on the secretory peak that accompanies the burst of preprandial activity. The present results have special relevance for the pathophysiology of anorexia nervosa and other compulsive behaviors.
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Affiliation(s)
- Martine Duclos
- PsyNuGen, INRA, UMR 1286, Université Bordeaux 2, F-33076 Bordeaux, France
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45
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Involvement of dopamine and opioids in the motivation to eat: influence of palatability, homeostatic state, and behavioral paradigms. Psychopharmacology (Berl) 2009; 203:475-87. [PMID: 19015837 DOI: 10.1007/s00213-008-1390-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2008] [Accepted: 10/21/2008] [Indexed: 10/21/2022]
Abstract
RATIONALE Motivation for food depends on several variables including food palatability, the homeostatic state of the organism, and the nature of the behavior required to obtain the reward. However, few studies to date have tried to evaluate motivation for food considering all these variables at the same time. Since dopamine and opioids have been deeply involved in the regulation of feeding, it is of interest to investigate their role considering all the mentioned variables. OBJECTIVES In this study, we evaluated the involvement of dopamine and endogenous opioids on food consumption and food motivation using behavioral paradigms that differ in the motor requirement to gain access to the reward, when food palatability and homeostatic state were taken into account. MATERIALS AND METHODS Pellets differentiated on palatability were offered to sated and restricted rats in consummatory tests and in different behavioral paradigms measuring motivational state, but requiring different motor outputs (runway and an operant progressive ratio 3 task). Peripheral injections of naloxone or flupenthixol were administered when these tasks were learned and stable. RESULTS Naloxone decreased food intake when pellets were palatable, while flupenthixol was without any effect. When considering motivation, naloxone decreased performances in both the runway and progressive ratio tests while flupenthixol was only effective in the progressive ratio test. CONCLUSIONS Impairing the opioid neurotransmission diminishes motivation to obtain food, possibly through a decrease in the perceived palatability of the food reward. The dopaminergic system appears to be more involved in the modulation of motivation to obtain food in a cost/benefit-related manner.
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46
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Verhagen LAW, Luijendijk MCM, Hillebrand JJG, Adan RAH. Dopamine antagonism inhibits anorectic behavior in an animal model for anorexia nervosa. Eur Neuropsychopharmacol 2009; 19:153-60. [PMID: 18977121 DOI: 10.1016/j.euroneuro.2008.09.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2008] [Revised: 08/29/2008] [Accepted: 09/30/2008] [Indexed: 11/24/2022]
Abstract
Excessive physical activity is commonly described as symptom of Anorexia Nervosa (AN). Activity-based anorexia (ABA) is considered an animal model for AN. The ABA model mimics severe body weight loss and increased physical activity. Suppression of hyperactivity by olanzapine in anorectic patients as well as in ABA rats suggested a role of dopamine and/or serotonin in this trait. Here, we investigated the effect of a non-selective dopamine antagonist in the ABA model. A dose-response curve of chronic treatment with the non-selective dopaminergic antagonist cis-flupenthixol was determined in the ABA model. Treatment reduced activity levels in both ad libitum fed and food-restricted rats. Treated ABA rats reduced body weight loss and increased food intake. These data support a role for dopamine in anorexia associated hyperactivity. Interestingly, in contrast to leptin treatment, food-anticipatory activity still persists in treated ABA rats.
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Affiliation(s)
- Linda A W Verhagen
- Rudolf Magnus Institute of Neuroscience, Department of Neuroscience & Pharmacology, University Medical Center Utrecht, Utrecht, The Netherlands
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47
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Velasco A, Cachero TG, Granda TG. Entrainment of circadian rhythms of cholesterol‐LDL, corticosterone and motor activity by feeding schedules in rats. BIOL RHYTHM RES 2008. [DOI: 10.1080/09291019409360288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- A. Velasco
- a Dept. Functional Biology (Physiology), Fac. Medicine , Univ. Oviedo , Spain
| | - T. G. Cachero
- a Dept. Functional Biology (Physiology), Fac. Medicine , Univ. Oviedo , Spain
| | - T. G. Granda
- a Dept. Functional Biology (Physiology), Fac. Medicine , Univ. Oviedo , Spain
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48
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Froy O, Chapnik N, Miskin R. The suprachiasmatic nuclei are involved in determining circadian rhythms during restricted feeding. Neuroscience 2008; 155:1152-9. [DOI: 10.1016/j.neuroscience.2008.06.060] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 06/22/2008] [Accepted: 06/29/2008] [Indexed: 12/31/2022]
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49
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Saper CB, Fuller PM. Inducible clocks: living in an unpredictable world. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2008; 72:543-50. [PMID: 18419313 DOI: 10.1101/sqb.2007.72.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
All mammals have daily cycles of behavior (e.g., wake-sleep and feeding), and physiology (e.g., hormone secretion and body temperature). These cycles are typically entrained to the external light/dark cycle, but they can be altered dramatically under conditions of restricted food availability, changes in ambient temperature, or the presence of external stimuli such as predators. During the past 30 years, one of the best studied of these responses has been the entrainment of circadian rhythms to food availability. Experiments in rats and other rodents have provided evidence for a food-entrainable oscillator (FEO) in the mammalian circadian timing system (CTS). Until recently, however, very little was understood about the locus subserving the FEO or the functional interrelationship between the FEO and the master CTS pacemaker, the suprachiasmatic nucleus (SCN). We discuss here new data on the location of the FEO and suggest that it may involve an oscillator mechanism that is "induced" by starvation and refeeding.
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Affiliation(s)
- C B Saper
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
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50
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Poulin AM, Timofeeva E. The dynamics of neuronal activation during food anticipation and feeding in the brain of food-entrained rats. Brain Res 2008; 1227:128-41. [DOI: 10.1016/j.brainres.2008.06.039] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Revised: 04/04/2008] [Accepted: 06/15/2008] [Indexed: 02/04/2023]
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