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Ugur M, Pieterse I, Meerhoff GF, Eggels L, Lamuadni K, Unmehopa UA, Booij J, la Fleur SE, Mul JD. Voluntary physical activity modulates self-selection of a high-caloric choice diet in male Wistar rats. Physiol Behav 2023; 268:114239. [PMID: 37196819 DOI: 10.1016/j.physbeh.2023.114239] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 05/12/2023] [Accepted: 05/13/2023] [Indexed: 05/19/2023]
Abstract
Physical exercise training has been positioned as a behavioral strategy to prevent or alleviate obesity via promotion of energy expenditure as well as modulation of energy intake resulting from changes in dietary preference. Brain adaptations underlying the latter process are incompletely understood. Voluntary wheel running (VWR) is a self-reinforcing rodent paradigm that mimics aspects of human physical exercise training. Behavioral and mechanistic insight from such fundamental studies can help optimize therapies that improve body weight and metabolic health based on physical exercise training in humans. To assess the effects of VWR on dietary self-selection, male Wistar rats were given access to a two-component "no-choice" control diet (CD; consisting of prefabricated nutritionally complete pellets and a bottle with tap water) or a four-component free-choice high-fat high-sucrose diet (fc-HFHSD; consisting of a container with prefabricated nutritionally complete pellets, a dish with beef tallow, a bottle with tap water, and a bottle with 30% sucrose solution). Metabolic parameters and baseline dietary self-selection behavior during sedentary (SED) housing were measured for 21 days, after which half of the animals were allowed to run on a vertical running wheel (VWR) for another 30 days. This resulted in four experimental groups (SEDCD, SEDfc-HFHSD, VWRCD, and VWRfc-HFHSD). Gene expression of opioid and dopamine neurotransmission components, which are associated with dietary self-selection, was assessed in the lateral hypothalamus (LH) and nucleus accumbens (NAc), two brain regions involved in reward-related behavior, following 51 and 30 days of diet consumption and VWR, respectively. Compared to CD controls, consumption of fc-HFHSD before and during VWR did not alter total running distances. VWR and fc-HFHSD had opposite effects on body weight gain and terminal fat mass. VWR transiently lowered caloric intake and increased and decreased terminal adrenal and thymus mass, respectively, independent of diet. VWR during fc-HFHSD consumption consistently increased CD self-selection, had an acute negative effect on fat self-selection, and a delayed negative effect on sucrose solution self-selection compared to SED controls. Gene expression of opioid and dopamine neurotransmission components in LH and NAc were unaltered by fc-HFHSD or VWR. We conclude that VWR modulates fc-HFHSD component self-selection in a time-dependent manner in male Wistar rats.
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Affiliation(s)
- Muzeyyen Ugur
- Amsterdam UMC, University of Amsterdam, Endocrinology Laboratory, Department of Laboratory Medicine, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands; Amsterdam Neuroscience, Cellular and Molecular Mechanisms, Amsterdam, The Netherlands; Amsterdam Gastroenterology Endocrinology & Metabolism, Amsterdam, The Netherlands; Metabolism and Reward Group, Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands
| | - Isabel Pieterse
- Amsterdam UMC, University of Amsterdam, Endocrinology Laboratory, Department of Laboratory Medicine, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Gideon F Meerhoff
- Brain Plasticity group, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Sciencepark 904, 1098 XH, Amsterdam, The Netherlands
| | - Leslie Eggels
- Amsterdam UMC, University of Amsterdam, Endocrinology Laboratory, Department of Laboratory Medicine, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Khalid Lamuadni
- Amsterdam UMC, University of Amsterdam, Endocrinology Laboratory, Department of Laboratory Medicine, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Unga A Unmehopa
- Amsterdam UMC, University of Amsterdam, Endocrinology Laboratory, Department of Laboratory Medicine, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Jan Booij
- Amsterdam UMC, University of Amsterdam, Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Susanne E la Fleur
- Amsterdam UMC, University of Amsterdam, Endocrinology Laboratory, Department of Laboratory Medicine, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands; Amsterdam Neuroscience, Cellular and Molecular Mechanisms, Amsterdam, The Netherlands; Amsterdam Gastroenterology Endocrinology & Metabolism, Amsterdam, The Netherlands; Metabolism and Reward Group, Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands
| | - Joram D Mul
- Amsterdam UMC, University of Amsterdam, Endocrinology Laboratory, Department of Laboratory Medicine, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands; Brain Plasticity group, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Sciencepark 904, 1098 XH, Amsterdam, The Netherlands.
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Flack KD, Stults-Kolehmainen MA, Creasy SA, Khullar S, Boullosa D, Catenacci VA, King N. Altered motivation states for physical activity and 'appetite' for movement as compensatory mechanisms limiting the efficacy of exercise training for weight loss. Front Psychol 2023; 14:1098394. [PMID: 37187558 PMCID: PMC10176969 DOI: 10.3389/fpsyg.2023.1098394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 03/23/2023] [Indexed: 05/17/2023] Open
Abstract
Weight loss is a major motive for engaging in exercise, despite substantial evidence that exercise training results in compensatory responses that inhibit significant weight loss. According to the Laws of Thermodynamics and the CICO (Calories in, Calories out) model, increased exercise-induced energy expenditure (EE), in the absence of any compensatory increase in energy intake, should result in an energy deficit leading to reductions of body mass. However, the expected negative energy balance is met with both volitional and non-volitional (metabolic and behavioral) compensatory responses. A commonly reported compensatory response to exercise is increased food intake (i.e., Calories in) due to increased hunger, increased desire for certain foods, and/or changes in health beliefs. On the other side of the CICO model, exercise training can instigate compensatory reductions in EE that resist the maintenance of an energy deficit. This may be due to decreases in non-exercise activity thermogenesis (NEAT), increases in sedentary behavior, or alterations in sleep. Related to this EE compensation, the motivational states associated with the desire to be active tend to be overlooked when considering compensatory changes in non-exercise activity. For example, exercise-induced alterations in the wanting of physical activity could be a mechanism promoting compensatory reductions in EE. Thus, one's desires, urges or cravings for movement-also known as "motivation states" or "appetence for activity"-are thought to be proximal instigators of movement. Motivation states for activity may be influenced by genetic, metabolic, and psychological drives for activity (and inactivity), and such states are susceptible to fatigue-or reward-induced responses, which may account for reductions in NEAT in response to exercise training. Further, although the current data are limited, recent investigations have demonstrated that motivation states for physical activity are dampened by exercise and increase after periods of sedentarism. Collectively, this evidence points to additional compensatory mechanisms, associated with motivational states, by which impositions in exercise-induced changes in energy balance may be met with resistance, thus resulting in attenuated weight loss.
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Affiliation(s)
- Kyle D. Flack
- Department of Dietetics and Human Nutrition, University of Kentucky, Lexington, KY, United States
| | - Matthew A. Stults-Kolehmainen
- Division of Digestive Health, Yale New Haven Hospital, New Haven, CT, United States
- Department of Biobehavioral Sciences, Teachers College, Columbia University, New York, NY, United States
| | - Seth A. Creasy
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Anschutz Health and Wellness Center, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Saumya Khullar
- School of Applied Sciences, Edinburgh Napier University, Edinburgh, United Kingdom
| | - Daniel Boullosa
- Faculty of Physical Activity and Sports Sciences, Universidad de León, León, Spain
- College of Healthcare Sciences, James Cook University, Townsville, QLD, Australia
- Graduate Program in Movement Sciences, Integrated Institute of Health, Federal University of Mato Grosso do Sul, Campo Grande, Brazil
| | - Victoria A. Catenacci
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Anschutz Health and Wellness Center, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Neil King
- School of Exercise and Nutrition Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD, Australia
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Mottarlini F, Rizzi B, Targa G, Fumagalli F, Caffino L. Long-lasting BDNF signaling alterations in the amygdala of adolescent female rats exposed to the activity-based anorexia model. Front Behav Neurosci 2022; 16:1087075. [PMID: 36570702 PMCID: PMC9772010 DOI: 10.3389/fnbeh.2022.1087075] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 11/16/2022] [Indexed: 12/12/2022] Open
Abstract
Introduction: Anorexia nervosa (AN) is a severe psychiatric disorder characterized by a pathological fear of gaining weight, excessive physical exercise, and emotional instability. Since the amygdala is a key region for emotion processing and BDNF has been shown to play a critical role in this process, we hypothesized that alteration in the amygdalar BDNF system might underline vulnerability traits typical of AN patients. Methods: To this end, adolescent female rats have been exposed to the Activity-Based Anorexia (ABA) protocol, characterized by the combination of caloric restriction and intense physical exercise. Results: The induction of the anorexic phenotype caused hyperactivity and body weight loss in ABA animals. These changes were paralleled by amygdalar hyperactivation, as measured by the up-regulation of cfos mRNA levels. In the acute phase of the pathology, we observed reduced Bdnf exon IX, exon IV, and exon VI gene expression, while mBDNF protein levels were enhanced, an increase that was, instead, uncoupled from its downstream signaling as the phosphorylation of TrkB, Akt, and S6 in ABA rats were reduced. Despite the body weight recovery observed 7 days later, the BDNF-mediated signaling was still downregulated at this time point. Discussion: Our findings indicate that the BDNF system is downregulated in the amygdala of adolescent female rats under these experimental conditions, which mimic the anorexic phenotype in humans, pointing to such dysregulation as a potential contributor to the altered emotional processing observed in AN patients. In addition, since the modulation of BDNF levels is observed in other psychiatric conditions, the persistent AN-induced changes of the BDNF system in the amygdala might contribute to explaining the onset of comorbid psychiatric disorders that persist in patients even beyond recovery from AN.
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Duration- and sex-dependent neural circuit control of voluntary physical activity. Psychopharmacology (Berl) 2022; 239:3697-3709. [PMID: 36195731 PMCID: PMC9768838 DOI: 10.1007/s00213-022-06243-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 09/20/2022] [Indexed: 10/10/2022]
Abstract
RATIONALE Exercise participation remains low despite clear benefits. Rats engage in voluntary wheel running (VWR) that follows distinct phases of acquisition, during which VWR escalates, and maintenance, during which VWR remains stable. Understanding mechanisms driving acquisition and maintenance of VWR could lead to novel strategies to promote exercise. The two phases of VWR resemble those that occur during operant conditioning and, therefore, might involve similar neural substrates. The dorsomedial (DMS) dorsal striatum (DS) supports the acquisition of operant conditioning, whereas the dorsolateral striatum (DLS) supports its maintenance. OBJECTIVES Here we sought to characterize the roles of DS subregions in VWR. Females escalate VWR and operant conditioning faster than males. Thus, we also assessed for sex differences. METHODS To determine the causal role of DS subregions in VWR, we pharmacologically inactivated the DMS or DLS of adult, male and female, Long-Evans rats during the two phases of VWR. The involvement of DA receptor 1 (D1)-expressing neurons in the DS was investigated by quantifying cfos mRNA within this neuronal population. RESULTS We observed that, in males, the DMS and DLS are critical for VWR exclusively during acquisition and maintenance, respectively. In females, the DMS is also critical only during acquisition, but the DLS contributes to VWR during both VWR phases. DLS D1 neurons could be an important driver of VWR escalation during acquisition. CONCLUSIONS The acquisition and maintenance of VWR involve unique neural substrates in the DS that vary by sex. Results reveal targets for sex-specific strategies to promote exercise.
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Ferrer-Pérez C, Reguilón MD, Miñarro J, Rodríguez-Arias M. Effect of Voluntary Wheel-Running Exercise on the Endocrine and Inflammatory Response to Social Stress: Conditioned Rewarding Effects of Cocaine. Biomedicines 2022; 10:biomedicines10102373. [PMID: 36289635 PMCID: PMC9598819 DOI: 10.3390/biomedicines10102373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 09/08/2022] [Accepted: 09/17/2022] [Indexed: 11/21/2022] Open
Abstract
The present paper evaluates the effect of physical activity on the increase of the conditioned rewarding effects of cocaine induced by intermittent social stress and on the neuroinflammatory response that contributes to the enhancement of drug response. For that purpose, three studies were designed in which social stress was induced in different samples of mice through a social-defeat protocol; the mice underwent an increase of physical activity by different modalities of voluntary wheel running (continuous and intermittent access). The results showed that continuous access to running wheels prior to stress enhanced the establishment of cocaine place preference, whereas an intermittent access exerted a protective effect. Wheel running contingent to cocaine administration prevented the development of conditioned preference, and if applied during the extinction of drug memories, it exerted a dual effect depending on the stress background of the animal. Our biological analysis revealed that increased sensitivity to cocaine may be related to the fact that wheel running promotes inflammation though the increase of IL-6 and BDNF levels. Together, these results highlight that physical exercise deeply impacts the organism’s response to stress and cocaine, and these effects should be taken into consideration in the design of a physical intervention.
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Affiliation(s)
- Carmen Ferrer-Pérez
- Department of Psychology and Sociology, Faculty of Humanities and Social Sciences, University of Zaragoza, 44003 Teruel, Spain
| | - Marina D. Reguilón
- Department of Psychobiology, Faculty of Psychology, Universitat de València, 46010 Valencia, Spain
| | - José Miñarro
- Department of Psychobiology, Faculty of Psychology, Universitat de València, 46010 Valencia, Spain
| | - Marta Rodríguez-Arias
- Department of Psychobiology, Faculty of Psychology, Universitat de València, 46010 Valencia, Spain
- Correspondence:
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He Y, Madeo G, Liang Y, Zhang C, Hempel B, Liu X, Mu L, Liu S, Bi GH, Galaj E, Zhang HY, Shen H, McDevitt RA, Gardner EL, Liu QS, Xi ZX. A red nucleus-VTA glutamate pathway underlies exercise reward and the therapeutic effect of exercise on cocaine use. SCIENCE ADVANCES 2022; 8:eabo1440. [PMID: 36054363 PMCID: PMC10848951 DOI: 10.1126/sciadv.abo1440] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 07/19/2022] [Indexed: 06/15/2023]
Abstract
Physical exercise is rewarding and protective against drug abuse and addiction. However, the neural mechanisms underlying these actions remain unclear. Here, we report that long-term wheel-running produced a more robust increase in c-fos expression in the red nucleus (RN) than in other brain regions. Anatomic and functional assays demonstrated that most RN magnocellular portion (RNm) neurons are glutamatergic. Wheel-running activates a subset of RNm glutamate neurons that project to ventral tegmental area (VTA) dopamine neurons. Optogenetic stimulation of this pathway was rewarding, as assessed by intracranial self-stimulation and conditioned place preference, whereas optical inhibition blocked wheel-running behavior. Running wheel access decreased cocaine self-administration and cocaine seeking during extinction. Last, optogenetic stimulation of the RNm-to-VTA glutamate pathway inhibited responding to cocaine. Together, these findings indicate that physical exercise activates a specific RNm-to-VTA glutamatergic pathway, producing exercise reward and reducing cocaine intake.
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Affiliation(s)
- Yi He
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
| | - Graziella Madeo
- Cellular Neurobiology Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
| | - Ying Liang
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
| | - Cindy Zhang
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
| | - Briana Hempel
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
| | - Xiaojie Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Lianwei Mu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Shui Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Guo-Hua Bi
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
| | - Ewa Galaj
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
| | - Hai-Ying Zhang
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
- Section on Molecular Neuroscience, National Institute of Mental Health, Bethesda, MD 20892, USA
| | - Hui Shen
- Cellular Neurobiology Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
| | - Ross A. McDevitt
- Cellular Neurobiology Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
- Comparative Medicine Section, National Institute on Aging, Intramural Research Program, Baltimore, MD 21224, USA
| | - Eliot L. Gardner
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
| | - Qing-song Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Zheng-Xiong Xi
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, USA
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Hebebrand J, Hildebrandt T, Schlögl H, Seitz J, Denecke S, Vieira D, Gradl-Dietsch G, Peters T, Antel J, Lau D, Fulton S. The role of hypoleptinemia in the psychological and behavioral adaptation to starvation: implications for anorexia nervosa. Neurosci Biobehav Rev 2022; 141:104807. [PMID: 35931221 DOI: 10.1016/j.neubiorev.2022.104807] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 06/11/2022] [Accepted: 07/31/2022] [Indexed: 12/17/2022]
Abstract
This narrative review aims to pinpoint mental and behavioral effects of starvation, which may be triggered by hypoleptinemia and as such may be amenable to treatment with leptin receptor agonists. The reduced leptin secretion results from the continuous loss of fat mass, thus initiating a graded triggering of diverse starvation related adaptive functions. In light of leptin receptors located in several peripheral tissues and many brain regions adaptations may extend beyond those of the hypothalamus-pituitary-end organ-axes. We focus on gastrointestinal tract and reward system as relevant examples of peripheral and central effects of leptin. Despite its association with extreme obesity, congenital leptin deficiency with its many parallels to a state of starvation allows the elucidation of mental symptoms amenable to treatment with exogenous leptin in both ob/ob mice and humans with this autosomal recessive disorder. For starvation induced behavioral changes with an intact leptin signaling we particularly focus on rodent models for which proof of concept has been provided for the causative role of hypoleptinemia. For humans, we highlight the major cognitive, emotional and behavioral findings of the Minnesota Starvation Experiment to contrast them with results obtained upon a lesser degree of caloric restriction. Evidence for hypoleptinemia induced mental changes also stems from findings obtained in lipodystrophies. In light of the recently reported beneficial cognitive, emotional and behavioral effects of metreleptin-administration in anorexia nervosa we discuss potential implications for the treatment of this eating disorder. We postulate that leptin has profound psychopharmacological effects in the state of starvation.
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Affiliation(s)
- Johannes Hebebrand
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Wickenburgstr. 21, 45134 Essen, Germany
| | - Tom Hildebrandt
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Haiko Schlögl
- Department of Endocrinology, Nephrology, Rheumatology, Division of Endocrinology, University Hospital Leipzig, Liebigstr. 20, 04103 Leipzig, Germany; Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Philipp-Rosenthal-Str. 27, 04103 Leipzig, Germany
| | - Jochen Seitz
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH University Hospital Aachen, Germany
| | - Saskia Denecke
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Wickenburgstr. 21, 45134 Essen, Germany
| | - Diana Vieira
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Wickenburgstr. 21, 45134 Essen, Germany
| | - Gertraud Gradl-Dietsch
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Wickenburgstr. 21, 45134 Essen, Germany
| | - Triinu Peters
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Wickenburgstr. 21, 45134 Essen, Germany
| | - Jochen Antel
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Essen, University of Duisburg-Essen, Wickenburgstr. 21, 45134 Essen, Germany
| | - David Lau
- Department of Nutrition, Neuroscience - University of Montreal & CRCHUM, Montréal QC H3T1J4, Canada
| | - Stephanie Fulton
- Department of Nutrition, Neuroscience - University of Montreal & CRCHUM, Montréal QC H3T1J4, Canada
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Santos MJ, Picco S, Fernández R, Pedreira ME, Boccia M, Klappenbach M, Krawczyk MC. Remembering how to run: a descriptive wheel run analysis in CF1 males and females mice. IBRO Neurosci Rep 2022; 12:333-341. [PMID: 35746966 PMCID: PMC9210458 DOI: 10.1016/j.ibneur.2022.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 04/15/2022] [Indexed: 12/01/2022] Open
Abstract
Physical exercise is known to have beneficial effects on general health and wellbeing in humans and it is also related to neuronal plasticity, increasing neurogenesis and consequently leading to improvements in processes such as learning and memory. In this sense, wheel running performance in mice appears as an extensively used behavioral approach for neurobiological studies. Here, we explored the running patterns in CF1 male and female mice allowing voluntary wheel running for 20 min along three consecutive days. We analyzed differences in the accumulated distance traveled, instant velocity, and latency to run and breaks taken in both males and females, comparing performance between days. Results revealed that after a first experience with the wheel, animals that had learnt how to run on day 1 quickly look forward to stepping into the wheel in subsequent training days, reflected by a significant increase in daily running distance and velocity. Further, no differences were found in the running performance between males and females. In summary, in a first experience with the wheel, animals get familiarized with the wheel and grow accustomed to it.
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Spadini S, Ferro M, Lamanna J, Malgaroli A. Activity-based anorexia animal model: a review of the main neurobiological findings. J Eat Disord 2021; 9:123. [PMID: 34600568 PMCID: PMC8487535 DOI: 10.1186/s40337-021-00481-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 09/15/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The genesis of anorexia nervosa (AN), a severe eating disorder with a pervasive effect on many brain functions such as attention, emotions, reward processing, cognition and motor control, has not yet been understood. Since our current knowledge of the genetic aspects of AN is limited, we are left with a large and diversified number of biological, psychological and environmental risk factors, called into question as potential triggers of this chronic condition with a high relapse rate. One of the most valid and used animal models for AN is the activity-based anorexia (ABA), which recapitulates important features of the human condition. This model is generated from naïve rodents by a self-motivated caloric restriction, where a fixed schedule food delivery induces spontaneous increased physical activity. AIM In this review, we sought to provide a summary of the experimental research conducted using the ABA model in the pursuit of potential neurobiological mechanism(s) underlying AN. METHOD The experimental work presented here includes evidence for neuroanatomical and neurophysiological changes in several brain regions as well as for the dysregulation of specific neurochemical synaptic and neurohormonal pathways. RESULTS The most likely hypothesis for the mechanism behind the development of the ABA phenotype relates to an imbalance of the neural circuitry that mediates reward processing. Evidence collected here suggests that ABA animals show a large set of alterations, involving regions whose functions extend way beyond the control of reward mechanisms and eating habits. Hence, we cannot exclude a primary role of these alterations from a mechanistic theory of ABA induction. CONCLUSIONS These findings are not sufficient to solve such a major enigma in neuroscience, still they could be used to design ad hoc further experimental investigation. The prospect is that, since treatment of AN is still challenging, the ABA model could be more effectively used to shed light on the complex AN neurobiological framework, thus supporting the future development of therapeutic strategies but also the identification of biomarkers and diagnostic tools. Anorexia Nervosa (AN) is a severe eating disorder with a dramatic effect on many functions of our brain, such as attention, emotions, cognition and motion control. Since our current knowledge of the genetic aspects behind the development of AN is still limited, many biological, psychological and environmental factors must be taken into account as potential triggers of this condition. One of the most valid animal models for studying AN is the activity-based anorexia (ABA). In this model, rodents spontaneously limit food intake and start performing increased physical activity on a running wheel, a result of the imposition of a fixed time schedule for food delivery. In this review, we provide a detailed summary of the experimental research conducted using the ABA model, which includes extended evidence for changes in the anatomy and function of the brain of ABA rodents. The hope is that such integrated view will support the design of future experiments that will shed light on the complex brain mechanisms behind AN. Such advanced knowledge is crucial to find new, effective strategies for both the early diagnosis of AN and for its treatment.
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Affiliation(s)
- Sara Spadini
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, Via Olgettina 58, 20132, Milan, Italy
| | - Mattia Ferro
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, Via Olgettina 58, 20132, Milan, Italy
- Department of Psychology, Sigmund Freud University, Milan, Italy
| | - Jacopo Lamanna
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, Via Olgettina 58, 20132, Milan, Italy
- Faculty of Psychology, Vita-Salute San Raffaele University, Milan, Italy
| | - Antonio Malgaroli
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, Via Olgettina 58, 20132, Milan, Italy.
- Faculty of Psychology, Vita-Salute San Raffaele University, Milan, Italy.
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Preference for vigorous exercise versus sedentary sucrose drinking: an animal model of anergia induced by dopamine receptor antagonism. Behav Pharmacol 2021; 31:553-564. [PMID: 32141919 DOI: 10.1097/fbp.0000000000000556] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Motivation has activational and directional components. Mesolimbic dopamine is critical for the regulation of behavioral activation and effort-related processes in motivated behaviors. Impairing mesolimbic dopamine function leads to fatigue and anergia, but leaves intact other aspects of reinforce seeking behaviors, such as the consummatory or hedonic component. In male Swiss mice, we characterized the impact of dopamine antagonism on the selection of concurrently presented stimuli that have different vigor requirements. We analyzed running wheel activity versus sucrose solution intake, typically used as a measure of anhedonia. Results are compared with data from nonconcurrent presentation to those stimuli. In the concurrent presentation experiment, control mice preferred to spend time running compared to sucrose intake. Dopamine antagonism shifted relative reinforcer preference, reducing time spent on the running wheel, but actually increasing time-consuming sucrose. Mice increased frequency of bouts for both reinforcers, suggesting that there was fatigue in the running wheel rather than aversion. Moreover, satiation or habituation by preexposing animals to both reinforcers did not shift preferences. In the nonconcurrent experiments, haloperidol reduced running wheel but had no impact on sucrose consumption. Dopamine antagonism did not change preference for sucrose or total volume consumed. Additional correlational analyses indicated that baseline differences in sucrose consumption were independent of baseline running or novelty exploration. Thus, dopamine antagonism seems to have anergic rather than anhedonic effects, and the concurrent presentation in this setting could be useful for assessing preferences based on effort requirements.
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11
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Contó MB, Dos Santos NB, Munhoz CD, Marcourakis T, D'Almeida V, Camarini R. Exposure to Running Wheels Prevents Ethanol Rewarding Effects: The Role of CREB and Deacetylases SIRT-1 and SIRT-2 in the Nucleus Accumbens and Prefrontal Cortex. Neuroscience 2021; 469:125-137. [PMID: 34175423 DOI: 10.1016/j.neuroscience.2021.06.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 06/16/2021] [Accepted: 06/17/2021] [Indexed: 10/21/2022]
Abstract
Alcohol use disorder is one of the most prevalent addictions, strongly influenced by environmental factors. Voluntary physical activity (VPA) has proven to be intrinsically reinforcing and we hypothesized that, as a non-drug reinforcer, VPA could mitigate ethanol-induced rewarding effects. The transcriptional factor cAMP response element binding protein (CREB), and deacetylases isozymes sirtuins 1 and 2 (SIRT-1 and SIRT-2) have a complex interplay and both play a role in the rewarding effects of ethanol. To test whether the exposure of mice to running wheels inhibits the development of ethanol-induced conditioned place preference (CPP), mice were assigned into four groups: housed in home cages with locked ("Sedentary") or unlocked running wheels (VPA), and treated with saline or 1.8 g/kg ethanol during the conditioning phase. The groups were referred as Saline-Sedentary, Saline-VPA, Ethanol-Sedentary and Ethanol-VPA. The expression of CREB, SIRT-1 and SIRT-2 were evaluated in the prefrontal cortex (PFC) and nucleus accumbens (NAc). VPA prevented the development of ethanol-induced CPP. VPA, ethanol and the combination of both inhibited pCREB and pCREB/CREB ratio in the NAc, suggesting that both reward stimuli can share similar patterns of CREB activation. However, we have found that ethanol-induced increased CREB levels were prevented by VPA. Both VPA groups presented lower SIRT-1 levels in the NAc compared to the Sedentary groups. Thus, exposure to running wheels prevented ethanol-rewarding effects and ethanol-induced increases in CREB in the NAc. The molecular alterations underlying CPP prevention may be related to a lower expression of CREB in the NAc of Ethanol-VPA compared to the respective Sedentary group, given the positive correlation between CPP and CREB levels in the Ethanol-Sedentary group.
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Affiliation(s)
- Marcos Brandão Contó
- Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de Sao Paulo, Sao Paulo, Brazil.
| | - Nilton Barreto Dos Santos
- Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Carolina Demarchi Munhoz
- Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Tania Marcourakis
- Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Vânia D'Almeida
- Departamento de Psicobiologia, Universidade Federal de São Paulo, Escola Paulista de Medicina (UNIFESP/EPM), Sao Paulo, Brazil
| | - Rosana Camarini
- Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de Sao Paulo, Sao Paulo, Brazil.
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12
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Zhang J, He ZX, Qu YS, Li LF, Wang LM, Yuan W, Hou WJ, Zhu YQ, Cai WQ, Zhang XN, Guo QQ, An SC, Jia R, Tai FD. Different baseline physical activity predicts susceptibility and resilience to chronic social defeat stress in mice: Involvement of dopamine neurons. Eur Neuropsychopharmacol 2021; 45:15-28. [PMID: 33730683 DOI: 10.1016/j.euroneuro.2021.02.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 02/10/2021] [Accepted: 02/15/2021] [Indexed: 02/07/2023]
Abstract
Physical inactivity, the fourth leading mortality risk factor worldwide, is associated with chronic mental illness. Identifying the mechanisms underlying different levels of baseline physical activity and the effects of these levels on the susceptibility to stress is very important. However, whether different levels of baseline physical activity influence the susceptibility and resilience to chronic social defeat stress (CSDS), and the underlying mechanisms in the brain remain unclear. The present study segregated wild-type mice into low baseline physical activity (LBPA) and high baseline physical activity (HBPA) groups based on short term voluntary wheel running (VWR). LBPA mice showed obvious susceptibility to CSDS, while HBPA mice were resilient to CSDS. In addition, the expression of tyrosine hydroxylase (TH) in the ventral tegmental area (VTA) was lower in LBPA mice than in HBPA mice. Furthermore, activation of TH neurons in the VTA of LBPA mice by chemogenetic methods increased the levels of VWR and resilience to CSDS. In contrast, inhibiting TH neurons in the VTA of HBPA mice lowered the levels of VWR and increased their susceptibility to CSDS. Thus, this study suggests that different baseline physical activities might be mediated by the dopamine system. This system also affects the susceptibility and resilience to CSDS, possibly via alteration of the baseline physical activity. This perspective on the neural control and impacts on VWR may aid the development of strategies to motivate and sustain voluntary physical activity. Furthermore, this can maximize the impacts of regular physical activity toward stress-reduction and health promotion.
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Affiliation(s)
- Jing Zhang
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China; School of Physical Education & Health, Nanning Normal University, Nanning 530100, China
| | - Zhi-Xiong He
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China
| | - Yi-Shan Qu
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China
| | - Lai-Fu Li
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China
| | - Li-Min Wang
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China
| | - Wei Yuan
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China
| | - Wen-Juan Hou
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China
| | - Ying-Qi Zhu
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China
| | - Wen-Qi Cai
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China
| | - Xue-Ni Zhang
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China
| | - Qian-Qian Guo
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China
| | - Shu-Cheng An
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China
| | - Rui Jia
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China; Cognition Neuroscience and Learning Division, Key Laboratory of Modern Teaching Technology, Ministry of Education, Shaanxi Normal University, Xi'an 710062, China.
| | - Fa-Dao Tai
- Institute of Brain and Behavioral Sciences, College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China; Cognition Neuroscience and Learning Division, Key Laboratory of Modern Teaching Technology, Ministry of Education, Shaanxi Normal University, Xi'an 710062, China.
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13
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Katsidoni V, Tzatzarakis MN, Karzi V, Thermos K, Kastellakis A, Panagis G. Differential effects of chronic voluntary wheel-running on morphine induced brain stimulation reward, motor activity and striatal dopaminergic activity. Behav Brain Res 2020; 394:112831. [PMID: 32721470 DOI: 10.1016/j.bbr.2020.112831] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/12/2020] [Accepted: 07/23/2020] [Indexed: 02/08/2023]
Abstract
Physical exercise could be a protective factor against the development of substance use disorders; however, a number of preclinical studies report reward-enhancing effects of exercise for various drugs of abuse. We examined the effects of chronic wheel-running on brain reward sensitivity, reaction to novelty, reward-facilitating and locomotor-stimulating effects of morphine, using the intracranial self-stimulation (ICSS) and the open field test (OFT). Male Sprague-Dawley rats were randomly assigned to a sedentary or exercised group. For the ICSS procedure, rats were implanted with electrodes and trained to respond for electrical stimulation. Several indices were recorded in the training phase to estimate brain reward sensitivity. Once responding was stable, the animals of both groups received systemic injections of morphine and their ICSS thresholds were measured with the curve-shift paradigm. Employing the OFT, basal and morphine-induced locomotor activity was measured. Finally, basal and morphine-evoked tissue levels of dopamine and its metabolites were determined in the striatum using gas chromatography/mass spectrometry. Chronic wheel-running decreased brain reward sensitivity and subsequently increased the reward-facilitating effect of morphine. Exercised animals demonstrated a decreased reaction to novelty and reduced morphine-induced locomotion. Lastly, dopaminergic activity was decreased in the striatum of exercised animals under basal conditions, whereas morphine administration led to an increase in dopamine turnover. These findings indicate that chronic voluntary exercise exerts divergent effects on reward function, psychomotor activity and the reward-facilitating and locomotor-activating effects of opioids during adulthood. Our results provide insights into the increased non-medical use of opioids among young athletes reported in the literature.
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Affiliation(s)
- Vicky Katsidoni
- Laboratory of Behavioral Neuroscience, Department of Psychology, School of Social Sciences, University of Crete, 74100, Rethymno, Crete, Greece
| | - Manolis N Tzatzarakis
- Laboratory of Toxicology, Medical School, University of Crete, 71003, Heraklion, Crete, Greece
| | - Vasiliki Karzi
- Laboratory of Toxicology, Medical School, University of Crete, 71003, Heraklion, Crete, Greece
| | - Kyriaki Thermos
- Laboratory of Pharmacology, Medical School, University of Crete, 71003, Heraklion, Crete, Greece
| | - Andreas Kastellakis
- Laboratory of Behavioral Neuroscience, Department of Psychology, School of Social Sciences, University of Crete, 74100, Rethymno, Crete, Greece
| | - George Panagis
- Laboratory of Behavioral Neuroscience, Department of Psychology, School of Social Sciences, University of Crete, 74100, Rethymno, Crete, Greece.
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Flack KD, Hays HM, Moreland J. Incentive sensitization for exercise reinforcement to increase exercise behaviors. J Health Psychol 2020; 26:2487-2504. [PMID: 32338538 DOI: 10.1177/1359105320914073] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Individuals can be sensitized to the reinforcing effects of exercise, although it is unknown if this process increases habitual exercise behavior. Sedentary men and women (body mass index: 25-35 kg/m2, N = 52) participated in a 12-week aerobic exercise intervention. Exercise reinforcement was determined by how much work was performed for exercise relative to a sedentary alternative in a progressive ratio schedule task. Habitual physical activity was assessed via accelerometry. Post-intervention increases in exercise reinforcement predicted increases in physical activity bouts among those who expended over 2000 kcal per week in exercise and who compensated for less than 50 percent of their exercise energy expenditure.
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Affiliation(s)
- Kyle D Flack
- Department of Deitetics and Human Nutrition, University of Kentucky, USA
| | - Harry M Hays
- Department of Deitetics and Human Nutrition, University of Kentucky, USA
| | - Jack Moreland
- Department of Deitetics and Human Nutrition, University of Kentucky, USA
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15
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Swenson S, Blum K, McLaughlin T, Gold MS, Thanos PK. The therapeutic potential of exercise for neuropsychiatric diseases: A review. J Neurol Sci 2020; 412:116763. [PMID: 32305746 DOI: 10.1016/j.jns.2020.116763] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 02/14/2020] [Accepted: 02/28/2020] [Indexed: 02/06/2023]
Abstract
Exercise is known to have a myriad of health benefits. There is much to be learned from the effects of exercise and its potential for prevention, attenuation and treatment of multiple neuropsychiatric diseases and behavioral disorders. Furthermore, recent data and research on exercise benefits with respect to major health crises, such as, that of opioid and general substance use disorders, make it very important to better understand and review the mechanisms of exercise and how it could be utilized for effective treatments or adjunct treatments for these diseases. In addition, mechanisms, epigenetics and sex differences are examined and discussed in terms of future research implications.
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Affiliation(s)
- Sabrina Swenson
- Behavioral Neuropharmacology and Neuroimaging Laboratory on Addictions, Clinical Research Institute on Addictions, Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biosciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - Kenneth Blum
- Western Univesity Health Sciences, Graduate College, Pomona, CA, USA
| | | | - Mark S Gold
- Washington University in St. Louis, School of Medicine, St. Louis, MO, USA
| | - Panayotis K Thanos
- Behavioral Neuropharmacology and Neuroimaging Laboratory on Addictions, Clinical Research Institute on Addictions, Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biosciences, State University of New York at Buffalo, Buffalo, NY, USA; Department of Psychology, State University of New York at Buffalo, Buffalo, NY, USA.
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16
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Carratalá-Ros C, López-Cruz L, SanMiguel N, Ibáñez-Marín P, Martínez-Verdú A, Salamone JD, Correa M. Preference for Exercise vs. More Sedentary Reinforcers: Validation of an Animal Model of Tetrabenazine-Induced Anergia. Front Behav Neurosci 2020; 13:289. [PMID: 32082126 PMCID: PMC7002319 DOI: 10.3389/fnbeh.2019.00289] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 12/19/2019] [Indexed: 11/13/2022] Open
Abstract
Physical activities can have intrinsic motivational or reinforcing properties. The choice to engage in voluntary physical activity is undertaken in relation to the selection of other alternatives, such as sedentary behaviors, drugs, or food intake. The mesolimbic dopamine (DA) system plays a critical role in behavioral activation or exertion of effort, and DA antagonism or depletion induces anergia in effort-based decision-making tasks. However, little is known about the neural mechanisms underlying the decision-making processes that establish preferences for sedentary vs. activity-based reinforcers. In the present work with male CD1 mice, we evaluated the effect of tetrabenazine (TBZ), a DA-depleting agent, on a three-choice T-maze task developed to assess preference between reinforcers with different behavioral activation requirements and sensory properties [i.e., a running wheel (RW) vs. sweet pellets or a neutral nonsocial odor]. We also studied the effects of TBZ on the forced swim test (FST), which measures climbing and swimming in a stressful setting, and on anxiety tests [dark-light (DL) box and elevated plus maze (EPM)]. In the three-choice task, TBZ reduced time running in the wheel but increased time spent consuming sucrose, thus indicating reduced activation but relatively intact sucrose reinforcement. The effect of TBZ was not mimicked by motivational manipulations that change the value of the reinforcers, such as making the RW aversive or harder to move, food-restricting the animals, inducing a binge-like eating pattern, or introducing social odors. In the FST, TBZ decreased time climbing (most active behavior) and increased immobility but did not affect anxiety in the DL or EPM. These results indicate that the three-choice T-maze task could be useful for assessing DA modulation of preferences for exercise based on activation and effort requirements, differentiating those effects from changes in preference produced by altering physical requirements, food restriction state, and stress during testing.
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Affiliation(s)
- Carla Carratalá-Ros
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, Castelló de la Plana, Spain
| | - Laura López-Cruz
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, Castelló de la Plana, Spain
| | - Noemí SanMiguel
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, Castelló de la Plana, Spain
| | - Patricia Ibáñez-Marín
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, Castelló de la Plana, Spain
| | - Andrea Martínez-Verdú
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, Castelló de la Plana, Spain
| | - John D Salamone
- Behavioral Neuroscience Division, University of Connecticut, Storrs, CT, United States
| | - Mercè Correa
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, Castelló de la Plana, Spain
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17
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Flack KD, Ufholz K, Johnson L, Roemmich JN. Increasing the Reinforcing Value of Exercise in Overweight Adults. Front Behav Neurosci 2019; 13:265. [PMID: 31849625 PMCID: PMC6902083 DOI: 10.3389/fnbeh.2019.00265] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 11/20/2019] [Indexed: 12/21/2022] Open
Abstract
Objectives: This study determined whether a moderate- or high-dose exercise program increases exercise reinforcement. Increasing the relative reinforcing value of exercise (RRVexercise; i.e., incentive sensitization of exercise) may increase the usual physical activity (PA) participation. Preference and/or tolerance for the intensity of exercise was also assessed. Design: Sedentary men and women (body mass index, BMI: 25–35 kg/m2) were randomized into parallel exercise training groups expending either 300 (n = 18) or 600 (n = 18) kcal/exercise session, five sessions/week, for 12 weeks. Methods: The RRVexercise was determined by how much work was performed for exercise relative to a sedentary alternative in a progressive ratio schedule task. Preference and tolerance for exercise intensity were determined by questionnaire. Results: RRVexercise increased (P < 0.05) in both groups. Exercise reinforcement, defined as the amount of work completed for exercise without taking sedentary activity into account, increased (P < 0.01) in the 600 kcal group only. Preference and tolerance for exercise intensity increased (P < 0.01) in both groups, which predicted increases in RRVexercise. Conclusion: Expending 300 or 600 kcal, 5 days/week increases RRVexercise, while 600 kcal, 5 days/week may be needed to increase exercise reinforcement.
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Affiliation(s)
- Kyle D Flack
- Department of Dietetics and Human Nutrition, University of Kentucky, Lexington, KY, United States
| | - Kelsey Ufholz
- United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Grand Forks Human Nutrition Research Center, Grand Forks, ND, United States
| | - LuAnn Johnson
- United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Grand Forks Human Nutrition Research Center, Grand Forks, ND, United States
| | - James N Roemmich
- United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Grand Forks Human Nutrition Research Center, Grand Forks, ND, United States
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18
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Sanchez V, Bakhti-Suroosh A, Chen A, Brunzell DH, Erisir A, Lynch WJ. Exercise during abstinence normalizes ultrastructural synaptic plasticity associated with nicotine-seeking following extended access self-administration. Eur J Neurosci 2019; 50:2707-2721. [PMID: 30888721 PMCID: PMC6742551 DOI: 10.1111/ejn.14408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 02/28/2019] [Accepted: 03/08/2019] [Indexed: 12/16/2022]
Abstract
Nicotine-craving progressively increases, or incubates, over abstinence following extended access self-administration. While not yet examined for nicotine, the incubation of cocaine-seeking is accompanied by changes in synaptic plasticity in the nucleus accumbens. Here, we determined whether such changes also accompany enhanced nicotine-seeking following extended access self-administration and abstinence, and whether exercise, a potential intervention for nicotine addiction, may exert its efficacy by normalizing these changes. Given that in humans, tobacco/nicotine use begins during adolescence, we used an adolescent-onset model. Nicotine-seeking was assessed in male rats following extended access nicotine or saline self-administration (23-hr/day, 10 days) and 10 days of abstinence, conditions known to induce the incubation of nicotine-seeking, using a within-session extinction/cue-induced reinstatement procedure. A subset of rats had 2-hr/day access to a running wheel during abstinence. Ultrastructural alterations of synapses in the nucleus accumbens core and shell were examined using electron microscopy. Nicotine-seeking was elevated following extended access self-administration and abstinence (in sedentary group), and levels of seeking were associated with an increase in the density of asymmetric (excitatory) and symmetric (inhibitory) synapses onto dendrites in the core, as well as longer asymmetric synapses onto spines, a marker of synaptic potentiation, in both the core and shell. Exercise normalized each of these changes; however, in the shell, exercise and nicotine similarly increased the synapse length. Together, these findings indicate an association between nicotine-seeking and synaptic plasticity in the nucleus accumbens, particularly the core, and indicate that the efficacy of exercise to reduce nicotine-seeking may be mediated by reversing these adaptations.
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Affiliation(s)
- Victoria Sanchez
- Department of Psychiatry and Neurobehavioral Sciences, University of Virginia, Charlottesville, Virginia
| | - Anousheh Bakhti-Suroosh
- Department of Psychiatry and Neurobehavioral Sciences, University of Virginia, Charlottesville, Virginia
| | - Andrew Chen
- Department of Psychology, University of Virginia, Charlottesville, Virginia
| | - Darlene H Brunzell
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia
| | - Alev Erisir
- Department of Psychology, University of Virginia, Charlottesville, Virginia
| | - Wendy J Lynch
- Department of Psychiatry and Neurobehavioral Sciences, University of Virginia, Charlottesville, Virginia
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Lee JR, Parker KE, Tapia M, Johns HW, Floros TG, Roberts MD, Booth FW, Will MJ. Voluntary wheel running effects on intra-accumbens opioid high-fat feeding and locomotor behavior in Sprague-Dawley and Wistar rat strains. Physiol Behav 2019; 206:67-75. [PMID: 30807769 DOI: 10.1016/j.physbeh.2019.02.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/29/2019] [Accepted: 02/11/2019] [Indexed: 12/30/2022]
Abstract
The present study examined the influence of physical activity vs. sedentary home cage conditions on baseline and opioid-driven high-fat feeding behaviors in two common strains of laboratory rats. Sprague-Dawley and Wistar rats were singly housed with either access to a voluntary running wheel (RUN) or locked-wheel (SED) for 5 weeks, before being stereotaxically implanted with bilateral cannulae targeting the nucleus accumbens. Following recovery, with RUN or SED conditions continuing the duration of the experiment, all rats were given 2 h daily access to a high-fat diet for 6 consecutive days to establish a stable baseline intake. Over the next 2 weeks, all subjects were administered the μ-opioid agonist D-Ala2, NMe-Phe4, Glyol5-enkephalin (DAMGO) (multiple dose range) or saline into the nucleus accumbens, immediately followed by 2 h access to a high-fat diet. Drug treatments were separated by at least 1 day and treatment order was counterbalanced. Baseline consumption of the high-fat diet during the 1-week baseline acclimation period did not differ between RUN and SED groups in either rat strain. Higher doses of DAMGO produced increased fat consumption in both strains of rats, yet no differences were observed between RUN vs. SED treated groups. However, SED treatment produced a greater locomotor response following intra-accumbens DAMGO administration, compared to the RUN condition, during the 2 h feeding session. The data suggest that the animals housed in sedentary versus voluntary wheel running conditions may differ in behavioral tolerance to the locomotor but not the orexigenic activating properties of intra-accumbens DAMGO treatment.
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Affiliation(s)
- Jenna R Lee
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA.
| | - Kyle E Parker
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA; Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA
| | - Melissa Tapia
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Howard W Johns
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Ted G Floros
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Michael D Roberts
- Department of Biomedical Sciences, University of Missouri, Columbia, MO, USA
| | - Frank W Booth
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA; Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA; Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
| | - Matthew J Will
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA; Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA.
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20
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Greenwood BN. The role of dopamine in overcoming aversion with exercise. Brain Res 2019; 1713:102-108. [DOI: 10.1016/j.brainres.2018.08.030] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 08/24/2018] [Accepted: 08/28/2018] [Indexed: 12/18/2022]
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21
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Inducing incentive sensitization of exercise reinforcement among adults who do not regularly exercise-A randomized controlled trial. PLoS One 2019; 14:e0216355. [PMID: 31063478 PMCID: PMC6504040 DOI: 10.1371/journal.pone.0216355] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 04/17/2019] [Indexed: 12/13/2022] Open
Abstract
Background Increasing exercise reinforcement, or decreasing sedentary reinforcement, may reduce sedentary activity and promote habitual exercise. Repeated exposures to a reinforcer may increase its reinforcing value (i.e., incentive sensitization). It is not yet known whether incentive sensitization occurs for exercise or factors associated with incentive sensitization for exercise reinforcement. The purpose was to determine whether exercise exposures increase exercise reinforcement relative to a sedentary alternative and whether this sensitization of exercise reinforcement would alter physical or sedentary behavior. This work also determined whether exercise dose, intensity, and preference and tolerance for exercise intensity were associated with incentive sensitization of exercise. Methods 104 sedentary men and women were randomized to exercise training groups with 89 completing the study. Groups included exercise exposures of 150 (n = 35) or 300 kcal/session (n = 34), 3 sessions/week for 6 weeks, or a non-exercise control group (n = 35). Assessments for exercise and sedentary behavior reinforcement (primary dependent variables) and activity and tolerance for exercise intensity were performed at baseline (week 0), post training (week 6), and post washout (week 10). Results The control group reduced (P = 0.022) relative reinforcing value of exercise, such that the 150 kcal group had a greater relative reinforcing value of exercise after the exercise treatment 150 kcal: 0.69 ± 0.07 to 0.74 ± 0.07; 300 kcal: 0.72 ± 0.07 to 0.63 ± 0.08, control: 0.72 ± 0.07 to 0.57 ± 0.08 mean ± SE. Increases in tolerance for exercise intensity discomfort were associated with increases in relative reinforcing value of exercise. Sedentary behavior reinforcement decreased in both exercise groups (150 kcal: 5.4 ± 4.3 to 1.8 ± 1.3; 300 kcal: 5.4 ± 4.3 to 3.1 ± 2.4, P<0.05), but remained unchanged in the control group (5.1 ± 4.0 to 6.1 ± 4.9, P>0.05). Sedentary activity decreased baseline to post-training in the 300 kcal group (546.5 ± 10.7 to 503.8 ± 11.8 minutes, P<0.01). Conclusion Small amounts of regular exercise may reduce the reinforcing value sedentary behavior. The process of incentive sensitization of exercise may include reducing the reinforcing value of competing sedentary activities. Developing tolerance to exercise discomfort of exercise may be critical to increasing exercise reinforcement.
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Lamanna J, Sulpizio S, Ferro M, Martoni R, Abutalebi J, Malgaroli A. Behavioral assessment of activity-based-anorexia: how cognition can become the drive wheel. Physiol Behav 2019; 202:1-7. [DOI: 10.1016/j.physbeh.2019.01.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 01/17/2019] [Accepted: 01/19/2019] [Indexed: 12/19/2022]
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Lynch CA, Porter B, Butler TR. Access to voluntary running wheel exercise: Prevention of anxiety-like behavior in chronically stressed rats, but potentiation of ethanol intake/preference. Physiol Behav 2019; 206:118-124. [PMID: 30946835 DOI: 10.1016/j.physbeh.2019.03.028] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 03/08/2019] [Accepted: 03/30/2019] [Indexed: 12/27/2022]
Abstract
The current study tested the effect of voluntary running on future anxiety-like behavior, physiological response to stress, and ethanol intake/preference, while including a chronically stressed group and healthy group housed conspecifics. When given concurrently, voluntary running reduces ethanol intake, though it is unknown what effect voluntary running will have on anxiety-like behavior, corticosterone response to stress, and ethanol intake/preference when exercise is allowed only prior to ethanol access. Adolescent male Long Evans rats arrived in the lab at postnatal day (PND) 21. At PND 27, rats were either socially isolated (SI; n = 1/cage) or group housed (GH; n = 4/cage). Half of each group was allowed access to a running wheel for 30 min for 24 days from PND 35-66, and half of each group was not allowed access to a running wheel. After the housing/running procedure, we tested anxiety-like behavior using the elevated plus maze and stress responsivity by measuring corticosterone (CORT) levels before and after a swim stressor; then, rats were allowed intermittent access to ethanol in two-bottle choice design for four weeks. In accord with our hypothesis, running reduced anxiety-like behavior in SI runners compared to non-runners. Swim stress increased CORT levels but there was no difference in the response among groups. In regard to ethanol intake and preference, running (irrespective of housing group) increased intake at the 30 min time point and preference at the 24 h time point. Altogether, these data show that access to voluntary exercise was successful in reducing anxiety-like behavior, but withdrawal of exercise access appeared to enhance ethanol intake/preference. We suggest that these data reflect hedonic substitution.
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Affiliation(s)
- Caroline A Lynch
- Department of Psychology, University of Dayton, 300 College Park, Dayton, OH 45469, United States of America
| | - Brandon Porter
- Department of Psychology, University of Dayton, 300 College Park, Dayton, OH 45469, United States of America
| | - Tracy R Butler
- Department of Psychology, University of Dayton, 300 College Park, Dayton, OH 45469, United States of America.
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Lespine LF, Tirelli E. Evidence for a long-term protection of wheel-running exercise against cocaine psychomotor sensitization in adolescent but not in adult mice. Behav Brain Res 2018; 349:63-72. [DOI: 10.1016/j.bbr.2018.04.054] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 04/30/2018] [Accepted: 04/30/2018] [Indexed: 12/16/2022]
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Mul JD. Voluntary exercise and depression-like behavior in rodents: are we running in the right direction? J Mol Endocrinol 2018; 60:R77-R95. [PMID: 29330149 DOI: 10.1530/jme-17-0165] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 01/11/2018] [Indexed: 12/18/2022]
Abstract
Acute or chronic exposure to stress can increase the risk to develop major depressive disorder, a severe, recurrent and common psychiatric condition. Depression places an enormous social and financial burden on modern society. Although many depressed patients are treated with antidepressants, their efficacy is only modest, underscoring the necessity to develop clinically effective pharmaceutical or behavioral treatments. Exercise training produces beneficial effects on stress-related mental disorders, indicative of clinical potential. The pro-resilient and antidepressant effects of exercise training have been documented for several decades. Nonetheless, the underlying molecular mechanisms and the brain circuitries involved remain poorly understood. Preclinical investigations using voluntary wheel running, a frequently used rodent model that mimics aspects of human exercise training, have started to shed light on the molecular adaptations, signaling pathways and brain nuclei underlying the beneficial effects of exercise training on stress-related behavior. In this review, I highlight several neurotransmitter systems that are putative mediators of the beneficial effects of exercise training on mental health, and review recent rodent studies that utilized voluntary wheel running to promote our understanding of exercise training-induced central adaptations. Advancements in our mechanistic understanding of how exercise training induces beneficial neuronal adaptations will provide a framework for the development of new strategies to treat stress-associated mental illnesses.
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Affiliation(s)
- Joram D Mul
- Department of Endocrinology and MetabolismAcademic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- Laboratory of EndocrinologyDepartment of Clinical Chemistry, University of Amsterdam, Amsterdam, the Netherlands
- Netherlands Institute for NeuroscienceRoyal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, the Netherlands
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The reinforcing value and liking of resistance training and aerobic exercise as predictors of adult's physical activity. Physiol Behav 2017; 179:284-289. [DOI: 10.1016/j.physbeh.2017.06.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 06/11/2017] [Accepted: 06/25/2017] [Indexed: 12/12/2022]
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Using wheel availability to shape running behavior of the rat towards improved behavioral and neurobiological outcomes. J Neurosci Methods 2017; 290:13-23. [DOI: 10.1016/j.jneumeth.2017.07.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 06/15/2017] [Accepted: 07/11/2017] [Indexed: 01/05/2023]
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Postreinforcement Pause Duration Varies Within a Session and With a Variable Response Requirement but Not as a Function of Prior Revolutions. PSYCHOLOGICAL RECORD 2017. [DOI: 10.1007/bf03395757] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Phillips C. Physical Activity Modulates Common Neuroplasticity Substrates in Major Depressive and Bipolar Disorder. Neural Plast 2017; 2017:7014146. [PMID: 28529805 PMCID: PMC5424494 DOI: 10.1155/2017/7014146] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 02/10/2017] [Accepted: 03/16/2017] [Indexed: 12/13/2022] Open
Abstract
Mood disorders (MDs) are chronic, recurrent mental diseases that affect millions of individuals worldwide. Although the biogenic amine model has provided some clinical utility, a need remains to better understand the interrelated mechanisms that contribute to neuroplasticity deficits in MDs and the means by which various therapeutics mitigate them. Of those therapeutics being investigated, physical activity (PA) has shown clear and consistent promise. Accordingly, the aims of this review are to (1) explicate key modulators, processes, and interactions that impinge upon multiple susceptibility points to effectuate neuroplasticity deficits in MDs; (2) explore the putative mechanisms by which PA mitigates these features; (3) review protocols used to induce the positive effects of PA in MDs; and (4) highlight implications for clinicians and researchers.
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Chen C, Nakagawa S, An Y, Ito K, Kitaichi Y, Kusumi I. The exercise-glucocorticoid paradox: How exercise is beneficial to cognition, mood, and the brain while increasing glucocorticoid levels. Front Neuroendocrinol 2017; 44:83-102. [PMID: 27956050 DOI: 10.1016/j.yfrne.2016.12.001] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 11/26/2016] [Accepted: 12/01/2016] [Indexed: 11/26/2022]
Abstract
Exercise is known to have beneficial effects on cognition, mood, and the brain. However, exercise also activates the hypothalamic-pituitary-adrenal axis and increases levels of the glucocorticoid cortisol (CORT). CORT, also known as the "stress hormone," is considered a mediator between chronic stress and depression and to link various cognitive deficits. Here, we review the evidence that shows that while both chronic stress and exercise elevate basal CORT levels leading to increased secretion of CORT, the former is detrimental to cognition/memory, mood/stress coping, and brain plasticity, while the latter is beneficial. We propose three preliminary answers to the exercise-CORT paradox. Importantly, the elevated CORT, through glucocorticoid receptors, functions to elevate dopamine in the medial prefrontal cortex under chronic exercise but not chronic stress, and the medial prefrontal dopamine is essential for active coping. Future inquiries may provide further insights to promote our understanding of this paradox.
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Affiliation(s)
- Chong Chen
- Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Shin Nakagawa
- Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan.
| | - Yan An
- Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Koki Ito
- Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Yuji Kitaichi
- Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Ichiro Kusumi
- Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
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Acosta W, Meek TH, Schutz H, Dlugosz EM, Garland T. Preference for Western diet coadapts in High Runner mice and affects voluntary exercise and spontaneous physical activity in a genotype-dependent manner. Behav Processes 2016; 135:56-65. [PMID: 27908664 DOI: 10.1016/j.beproc.2016.11.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Revised: 11/19/2016] [Accepted: 11/27/2016] [Indexed: 01/06/2023]
Abstract
Do animals evolve (coadapt) to choose diets that positively affect their performance abilities? We addressed this question from a microevolutionary perspective by examining preference for Western diet (WD: high in fat and sugar, but lower in protein) versus standard rodent chow in adults of both sexes from 4 lines of mice selectively bred for high levels of voluntary wheel running (High Runner or HR lines) and 4 non-selected control (C) lines. We also assessed whether food preference or substitution affects physical activity (wheel running and/or spontaneous physical activity [SPA] in the attached home cages). In experiment 1 (generation 56), mice were given 6days of wheel acclimation (as is used routinely to pick breeders in the selection experiment) prior to a 2-day food choice trial. In experiment 2 (generation 56), 17days of wheel acclimation allowed mice to reach a stable level of daily running, followed by a 7-day food-choice trial. In experiment 3 (generation 58), mice had 6days of wheel acclimation with standard chow, after which half were switched to WD for two days. In experiment 1, WD was highly preferred by all mice, with somewhat greater preference in male C mice. In experiment 2, wheel running increased and SPA decreased continuously for the first 14days of adult wheel testing, followed by 3-day plateaus in both. During the subsequent 7-day food choice trial, HR mice of both sexes preferred WD significantly more than did C mice; moreover, wheel running increased in all groups except males from C lines, with the increase being significantly greater in HR than C, while SPA declined further in all groups. In experiment 3, the effect of being switched to WD depended on both linetype and sex. On standard chow, only HR females showed a significant change in wheel running during nights 7+8, increasing by 10%. In contrast, when switched to WD, C females (+28%), HR females (+33%), and HR males (+10%) all significantly increased their daily wheel-running distances. Our results show for the first time that dietary preferences can coadapt in response to selection on activity levels.
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Affiliation(s)
- Wendy Acosta
- Department of Biology, University of California, Riverside, CA 92521, USA
| | - Thomas H Meek
- Department of Biology, University of California, Riverside, CA 92521, USA
| | - Heidi Schutz
- Department of Biology, University of California, Riverside, CA 92521, USA
| | | | - Theodore Garland
- Department of Biology, University of California, Riverside, CA 92521, USA.
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Rawashdeh O, Clough SJ, Hudson RL, Dubocovich ML. Learned motivation drives circadian physiology in the absence of the master circadian clock. FASEB J 2016; 31:388-399. [PMID: 27733449 DOI: 10.1096/fj.201600926r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 09/28/2016] [Indexed: 01/23/2023]
Abstract
The suprachiasmatic nucleus (SCN)-often referred to as the master circadian clock-is essential in generating physiologic rhythms and orchestrating synchrony among circadian clocks. This study tested the hypothesis that periodic motivation induced by rhythmically pairing 2 reinforcing stimuli [methamphetamine (Meth) and running wheel (RW)] restores autonomous circadian activity in arrhythmic SCN-lesioned (SCNX) C3H/HeN mice. Sham-surgery and SCNX mice were treated with either Meth (1.2 mg/kg, i.p.) or vehicle in association, dissociation, or absence of an RW. Only the association of Meth treatment and restricted RW access successfully reestablished entrained circadian rhythms in mice with SCNX. RW-likely acting as a link between the circadian and reward systems-promotes circadian entrainment of activity. We conclude that a conditioned drug response is a powerful tool to entrain, drive, and restore circadian physiology. Furthermore, an RW should be recognized as a potent input signal in addition to the conventional use as an output signal.-Rawashdeh, O., Clough, S. J., Hudson, R. L., Dubocovich, M. L. Learned motivation drives circadian physiology in the absence of the master circadian clock.
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Affiliation(s)
- Oliver Rawashdeh
- Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA
| | - Shannon J Clough
- Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA
| | - Randall L Hudson
- Department of Physiology and Biophysics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, New York, USA
| | - Margarita L Dubocovich
- Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA;
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Radell ML, Myers CE, Beck KD, Moustafa AA, Allen MT. The Personality Trait of Intolerance to Uncertainty Affects Behavior in a Novel Computer-Based Conditioned Place Preference Task. Front Psychol 2016; 7:1175. [PMID: 27555829 PMCID: PMC4977360 DOI: 10.3389/fpsyg.2016.01175] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 07/25/2016] [Indexed: 12/05/2022] Open
Abstract
Recent work has found that personality factors that confer vulnerability to addiction can also affect learning and economic decision making. One personality trait which has been implicated in vulnerability to addiction is intolerance to uncertainty (IU), i.e., a preference for familiar over unknown (possibly better) options. In animals, the motivation to obtain drugs is often assessed through conditioned place preference (CPP), which compares preference for contexts where drug reward was previously received. It is an open question whether participants with high IU also show heightened preference for previously rewarded contexts. To address this question, we developed a novel computer-based CPP task for humans in which participants guide an avatar through a paradigm in which one room contains frequent reward (i.e., rich) and one contains less frequent reward (i.e., poor). Following exposure to both contexts, subjects are assessed for preference to enter the previously rich and previously poor room. Individuals with low IU showed little bias to enter the previously rich room first, and instead entered both rooms at about the same rate which may indicate a foraging behavior. By contrast, those with high IU showed a strong bias to enter the previously rich room first. This suggests an increased tendency to chase reward in the intolerant group, consistent with previously observed behavior in opioid-addicted individuals. Thus, the personality factor of high IU may produce a pre-existing cognitive bias that provides a mechanism to promote decision-making processes that increase vulnerability to addiction.
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Affiliation(s)
- Milen L Radell
- Department of Veterans Affairs, Veterans Affairs New Jersey Health Care System, East OrangeNJ, USA; Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers University, NewarkNJ, USA
| | - Catherine E Myers
- Department of Veterans Affairs, Veterans Affairs New Jersey Health Care System, East OrangeNJ, USA; Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers University, NewarkNJ, USA
| | - Kevin D Beck
- Department of Veterans Affairs, Veterans Affairs New Jersey Health Care System, East OrangeNJ, USA; Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers University, NewarkNJ, USA
| | - Ahmed A Moustafa
- School of Social Sciences and Psychology and Marcs Institute for Brain and Behaviour, University of Western Sydney, Sydney NSW, Australia
| | - Michael Todd Allen
- School of Psychological Sciences, University of Northern Colorado, Greeley CO, USA
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Park YM, Kanaley JA, Padilla J, Zidon T, Welly RJ, Will MJ, Britton SL, Koch LG, Ruegsegger GN, Booth FW, Thyfault JP, Vieira-Potter VJ. Effects of intrinsic aerobic capacity and ovariectomy on voluntary wheel running and nucleus accumbens dopamine receptor gene expression. Physiol Behav 2016; 164:383-9. [PMID: 27297873 DOI: 10.1016/j.physbeh.2016.06.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Revised: 05/18/2016] [Accepted: 06/07/2016] [Indexed: 12/29/2022]
Abstract
UNLABELLED Rats selectively bred for high (HCR) and low (LCR) aerobic capacity show a stark divergence in wheel running behavior, which may be associated with the dopamine (DA) system in the brain. HCR possess greater motivation for voluntary running along with greater brain DA activity compared to LCR. We recently demonstrated that HCR are not immune to ovariectomy (OVX)-associated reductions in spontaneous cage (i.e. locomotor) activity. Whether HCR and LCR rats differ in their OVX-mediated voluntary wheel running response is unknown. PURPOSE To determine whether HCR are protected from OVX-associated reduction in voluntary wheel running. METHODS Forty female HCR and LCR rats (age ~27weeks) had either SHM or OVX operations, and given access to a running wheel for 11weeks. Weekly wheel running distance was monitored throughout the intervention. Nucleus accumbens (NAc) was assessed for mRNA expression of DA receptors at sacrifice. RESULTS Compared to LCR, HCR ran greater distance and had greater ratio of excitatory/inhibitory DA mRNA expression (both line main effects, P<0.05). Wheel running distance was significantly, positively correlated with the ratio of excitatory/inhibitory DA mRNA expression across animals. In both lines, OVX reduced wheel running (P<0.05). Unexpectedly, although HCR started with significantly greater voluntary wheel running, they had greater OVX-induced reduction in wheel running than LCR such that no differences were found 11weeks after OVX between HCROVX and LCROVX (interaction, P<0.05). This significant reduction in wheel running in HCR was associated with an OVX-mediated reduction in the ratio of excitatory/inhibitory DA mRNA expression. CONCLUSION The DA system in the NAc region may play a significant role in motivation to run in female rats. Compared to LCR, HCR rats run significantly more, which associates with greater ratio of excitatory/inhibitory DA mRNA expression. However, despite greater inherent motivation to run and an associated brain DA mRNA expression profile, HCR rats are not protected against OVX-induced reduction in wheel running or OVX-mediated reduction in the ratio of excitatory/inhibitory DA receptor mRNA expression. OVX-mediated reduction in motivated physical activity may be partially explained by a reduced ratio of excitatory/inhibitory DA receptor mRNA expression for which intrinsic fitness does not confer protection.
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Affiliation(s)
- Young-Min Park
- Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA
| | - Jill A Kanaley
- Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA
| | - Jaume Padilla
- Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA; Child Health, University of Missouri, Columbia, MO, USA; Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
| | - Terese Zidon
- Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA
| | - Rebecca J Welly
- Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA
| | - Matthew J Will
- Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Steven L Britton
- Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Lauren G Koch
- Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Frank W Booth
- Biomedical Sciences, University of Missouri, Columbia, MO, USA
| | - John P Thyfault
- Department of Molecular Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA
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Nicastro TM, Greenwood BN. Central monoaminergic systems are a site of convergence of signals conveying the experience of exercise to brain circuits involved in cognition and emotional behavior. Curr Zool 2016; 62:293-306. [PMID: 29491917 PMCID: PMC5804240 DOI: 10.1093/cz/zow027] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 02/11/2016] [Indexed: 01/04/2023] Open
Abstract
Physical activity can enhance cognitive function and increase resistance against deleterious effects of stress on mental health. Enhanced cognitive function and stress resistance produced by exercise are conserved among vertebrates, suggesting that ubiquitous mechanisms may underlie beneficial effects of exercise. In the current review, we summarize the beneficial effects of exercise on cognitive function and stress resistance and discuss central and peripheral signaling factors that may be critical for conferring the effects of physical activity to brain circuits involved in cognitive function and stress. Additionally, it is suggested that norepinephrine and serotonin, highly conserved monoamines that are sensitive to exercise and able to modulate behavior in multiple species, could represent a convergence between peripheral and central exercise signals that mediate the beneficial effects of exercise. Finally, we offer the novel hypothesis that thermoregulation during exercise could contribute to the emotional effects of exercise by activating a subset of temperature-sensitive serotonergic neurons in the dorsal raphe nucleus that convey anxiolytic and stress-protective signals to forebrain regions. Throughout the review, we discuss limitations to current approaches and offer strategies for future research in exercise neuroscience.
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Exposure to sucrose during periods of withdrawal does not reduce cocaine-seeking behavior in rats. Sci Rep 2016; 6:23272. [PMID: 26997496 PMCID: PMC4800416 DOI: 10.1038/srep23272] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 02/26/2016] [Indexed: 01/09/2023] Open
Abstract
Concomitant access to drugs of abuse and alternative rewards such as sucrose has been shown to decrease addiction-related behaviors in animals. Here we investigated whether access to sucrose during abstinence in contexts that are temporally and physically distinct from drug-related contexts could reduce subsequent drug seeking. In addition, we investigated whether a history of cocaine self-administration would alter the rewarding effects of sucrose. Rats self-administered cocaine for ten sessions, while yoked-saline rats received only saline injections, and then we subjected them to a 30-day withdrawal period during which they had access to water and sucrose continuously or intermittently according to a schedule that induces binge-drinking behavior. At the end of the withdrawal period, rats were tested for cocaine seeking behavior during a single 6 h session. We found that exposure to cocaine increased sucrose consumption only when rats had intermittent access to sucrose, but exposure to sucrose did not alter drug seeking regardless of the schedule of access. These results suggest that exposure to cocaine cross-sensitizes to the rewarding effects of sucrose, but exposure to sucrose during abstinence, temporally and physically distinct from drug-related environments, does not to reduce drug seeking.
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Herrera JJ, Fedynska S, Ghasem PR, Wieman T, Clark PJ, Gray N, Loetz E, Campeau S, Fleshner M, Greenwood BN. Neurochemical and behavioural indices of exercise reward are independent of exercise controllability. Eur J Neurosci 2016; 43:1190-202. [PMID: 26833814 DOI: 10.1111/ejn.13193] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 01/18/2016] [Accepted: 01/26/2016] [Indexed: 11/27/2022]
Abstract
Brain reward circuits are implicated in stress-related psychiatric disorders. Exercise reduces the incidence of stress-related disorders, but the contribution of exercise reward to stress resistance is unknown. Exercise-induced stress resistance is independent of exercise controllability; both voluntary running (VR) and forced running (FR) protect rats against the anxiety-like and depression-like behavioural consequences of stress. Voluntary exercise is a natural reward, but whether rats find FR rewarding is unknown. Moreover, the contribution of dopamine (DA) and striatal reward circuits to exercise reward is not well characterized. Adult, male rats were assigned to locked wheels, VR, or FR groups. FR rats were forced to run in a pattern resembling the natural wheel running behavior of rats. Both VR and FR increased the reward-related plasticity marker ΔFosB in the dorsal striatum and nucleus accumbens, and increased the activity of DA neurons in the lateral ventral tegmental area, as revealed by immunohistochemistry for tyrosine hydroxylase and pCREB. Both VR and FR rats developed conditioned place preference (CPP) to the side of a CPP chamber paired with exercise. Re-exposure to the exercise-paired side of the CPP chamber elicited conditioned increases in cfos mRNA in direct-pathway (dynorphin-positive) neurons in the dorsal striatum and nucleus accumbens in both VR and FR rats, and in tyrosine hydroxylase-positive neurons in the lateral ventral tegmental area of VR rats only. The results suggest that the rewarding effects of exercise are independent of exercise controllability and provide insight into the DA and striatal circuitries involved in exercise reward and exercise-induced stress resistance.
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Affiliation(s)
- Jonathan J Herrera
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Sofiya Fedynska
- Department of Psychology, University of Colorado Denver, CB 173, PO Box 173364, Denver, 80217, CO, USA
| | - Parsa R Ghasem
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Tyler Wieman
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Peter J Clark
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Nathan Gray
- Department of Psychology, University of Colorado Denver, CB 173, PO Box 173364, Denver, 80217, CO, USA
| | - Esteban Loetz
- Department of Psychology, University of Colorado Denver, CB 173, PO Box 173364, Denver, 80217, CO, USA
| | - Serge Campeau
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, CO, USA.,Center for Neuroscience, University of Colorado Boulder, Boulder, CO, USA
| | - Monika Fleshner
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA.,Center for Neuroscience, University of Colorado Boulder, Boulder, CO, USA
| | - Benjamin N Greenwood
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA.,Center for Neuroscience, University of Colorado Boulder, Boulder, CO, USA
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Correa M, Pardo M, Bayarri P, López-Cruz L, San Miguel N, Valverde O, Ledent C, Salamone JD. Choosing voluntary exercise over sucrose consumption depends upon dopamine transmission: effects of haloperidol in wild type and adenosine A₂AKO mice. Psychopharmacology (Berl) 2016; 233:393-404. [PMID: 26554387 DOI: 10.1007/s00213-015-4127-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 10/12/2015] [Indexed: 11/25/2022]
Abstract
RATIONALE Mesolimbic dopamine (DA) regulates behavioral activation and effort-related decision-making in motivated behaviors. Mesolimbic DA D2 receptors are co-localized with adenosine A2A receptors, and they interact in an antagonistic manner. OBJECTIVES A T-maze task was developed to assess dopaminergic involvement in preference between a reinforcer that involves vigorous voluntary activity (running wheel) and a reinforcer that requires minimal behavioral activation (sucrose pellets). Haloperidol (D2 antagonist) was administered to adenosine A2A receptor knockout (A2AKO) and wild-type (WT) littermate controls to assess the involvement of these two receptors in the selection of running wheel activity versus sucrose consumption. RESULTS Under control conditions, mice spent more time running and less time eating. In WT mice, haloperidol reduced time running but actually increased time-consuming sucrose. However, A2AKO mice did not show the haloperidol-induced shift from running wheel activity to sucrose intake. Prefeeding reduced sucrose consumption in the T-maze in both strains, indicating that this paradigm is sensitive to motivational devaluation. Haloperidol increased c-Fos immunoreactivity in anterior cingulate cortex (ACg) and nucleus accumbens (Acb) core of WT but not KO mice. CONCLUSIONS These results indicate that after DA antagonism, the preference for vigorous physical activity is reduced, while palatable food selection increases. Adenosine A2A receptor deletion provides resistance to these effects of D2 receptor antagonism. These two receptors in Acb core and ACg seem to be involved in the regulation of the intrinsic reinforcing characteristics of voluntary exercise but not in the regulation of the primary reinforcing characteristics of palatable sedentary reinforcers.
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Affiliation(s)
- Mercè Correa
- Department of Psychobiology, Universitat Jaume I, Castelló, Spain.
| | - Marta Pardo
- Department of Psychobiology, Universitat Jaume I, Castelló, Spain.
| | - Pilar Bayarri
- Department of Psychobiology, Universitat Jaume I, Castelló, Spain.
| | - Laura López-Cruz
- Department of Psychobiology, Universitat Jaume I, Castelló, Spain.
| | - Noemí San Miguel
- Department of Psychobiology, Universitat Jaume I, Castelló, Spain.
| | - Olga Valverde
- Department of Experimental and Health Sciences, Universitat Pompeu Fabra and IMIM-Hospital del Mar Research Institute, Barcelona, Spain.
| | - Catherine Ledent
- Institut de Recherche Interdisciplinaire en Biologie Humaine et Moléculaire, Université Libre de Bruxelles, IRIBHM, Bruxelles, Belgium.
| | - John D Salamone
- Department of Psychology, University of Connecticut, Storrs, CT, USA.
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Caspr3-Deficient Mice Exhibit Low Motor Learning during the Early Phase of the Accelerated Rotarod Task. PLoS One 2016; 11:e0147887. [PMID: 26807827 PMCID: PMC4726695 DOI: 10.1371/journal.pone.0147887] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 01/08/2016] [Indexed: 11/19/2022] Open
Abstract
Caspr3 (Contactin-associated protein-like 3, Cntnap3) is a neural cell adhesion molecule belonging to the Caspr family. We have recently shown that Caspr3 is expressed abundantly between the first and second postnatal weeks in the mouse basal ganglia, including the striatum, external segment of the globus pallidus, subthalamic nucleus, and substantia nigra. However, its physiological role remains largely unknown. In this study, we conducted a series of behavioral analyses on Capsr3-knockout (KO) mice and equivalent wild-type (WT) mice to investigate the role of Caspr3 in brain function. No significant differences were observed in most behavioral traits between Caspr3-KO and WT mice, but we found that Caspr3-KO mice performed poorly during the early phase of the accelerated rotarod task in which latency to falling off a rod rotating with increasing velocity was examined. In the late phase, the performance of the Caspr3-KO mice caught up to the level of WT mice, suggesting that the deletion of Caspr3 caused a delay in motor learning. We then examined changes in neural activity after training on the accelerated rotarod by conducting immunohistochemistry using antibody to c-Fos, an indirect marker for neuronal activity. Experience of the accelerated rotarod task caused increases in the number of c-Fos-positive cells in the dorsal striatum, cerebellum, and motor cortex in both Caspr3-KO and WT mice, but the number of c-Fos-positive cells was significantly lower in the dorsal striatum of Caspr3-KO mice than in that of WT mice. The expression of c-Fos in the ventral striatum of Caspr3-KO and WT mice was not altered by the training. Our findings suggest that reduced activation of neural cells in the dorsal striatum in Caspr3-KO mice leads to a decline in motor learning in the accelerated rotarod task.
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Mika A, Bouchet CA, Bunker P, Hellwinkel JE, Spence KG, Day HEW, Campeau S, Fleshner M, Greenwood BN. Voluntary exercise during extinction of auditory fear conditioning reduces the relapse of fear associated with potentiated activity of striatal direct pathway neurons. Neurobiol Learn Mem 2015; 125:224-35. [PMID: 26454156 PMCID: PMC4648665 DOI: 10.1016/j.nlm.2015.10.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 09/22/2015] [Accepted: 10/01/2015] [Indexed: 12/22/2022]
Abstract
Relapse of previously extinguished fear presents a significant, pervasive obstacle to the successful long-term treatment of anxiety and trauma-related disorders. Thus, identification of a novel means to enhance fear extinction to stand the passage of time and generalize across contexts is of the utmost importance. Acute bouts of exercise can be used as inexpensive, noninvasive treatment strategies to reduce anxiety, and have been shown to enhance memory for extinction when performed in close temporal proximity to the extinction session. However, it is unclear whether acute exercise can be used to prevent relapse of fear, and the neural mechanisms underlying this potential effect are unknown. The current study therefore examined whether acute exercise during extinction of auditory fear can protect against the later relapse of fear. Male F344 rats lacking an extended history of wheel running were conditioned to fear a tone CS and subsequently extinguished within either a freely mobile running wheel, a locked wheel, or a control context lacking a wheel. Rats exposed to fear extinction within a freely mobile wheel ran during fear extinction, and demonstrated reduced fear as well as attenuated corticosterone levels during re-exposure to the extinguished CS during the relapse test in a novel context 1week later. Examination of cfos mRNA patterns elicited by re-exposure to the extinguished CS during the relapse test revealed that acute exercise during extinction decreased activation of brain circuits classically involved in driving fear expression and interestingly, increased activity within neurons of the direct striatal pathway involved in reward signaling. These data suggest that exercise during extinction reduces relapse through a mechanism involving the direct pathway of the striatum. It is suggested that a positive affective state could become associated with the CS during exercise during extinction, thus resulting in a relapse-resistant extinction memory.
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Affiliation(s)
- Agnieszka Mika
- Department of Integrative Physiology, University of Colorado Boulder, 354 UCB, Boulder, CO 80309, United States; Center for Neuroscience, University of Colorado Boulder, UCB Boulder 80309, United States
| | - Courtney A Bouchet
- Department of Integrative Biology, University of Colorado Denver, Denver, CO 80217, United States
| | - Preston Bunker
- Department of Integrative Physiology, University of Colorado Boulder, 354 UCB, Boulder, CO 80309, United States
| | - Justin E Hellwinkel
- Department of Integrative Physiology, University of Colorado Boulder, 354 UCB, Boulder, CO 80309, United States
| | - Katie G Spence
- Department of Integrative Physiology, University of Colorado Boulder, 354 UCB, Boulder, CO 80309, United States
| | - Heidi E W Day
- Department of Psychology and Neuroscience, University of Colorado Boulder, 345 UCB Boulder CO 80309, United States; Center for Neuroscience, University of Colorado Boulder, UCB Boulder 80309, United States
| | - Serge Campeau
- Department of Psychology and Neuroscience, University of Colorado Boulder, 345 UCB Boulder CO 80309, United States; Center for Neuroscience, University of Colorado Boulder, UCB Boulder 80309, United States
| | - Monika Fleshner
- Department of Integrative Physiology, University of Colorado Boulder, 354 UCB, Boulder, CO 80309, United States; Center for Neuroscience, University of Colorado Boulder, UCB Boulder 80309, United States
| | - Benjamin N Greenwood
- Department of Psychology, University of Colorado Denver, CO 80217, United States.
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Fernandes MFA, Matthys D, Hryhorczuk C, Sharma S, Mogra S, Alquier T, Fulton S. Leptin Suppresses the Rewarding Effects of Running via STAT3 Signaling in Dopamine Neurons. Cell Metab 2015; 22:741-9. [PMID: 26341832 DOI: 10.1016/j.cmet.2015.08.003] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 06/12/2015] [Accepted: 08/05/2015] [Indexed: 01/29/2023]
Abstract
The adipose hormone leptin potently influences physical activity. Leptin can decrease locomotion and running, yet the mechanisms involved and the influence of leptin on the rewarding effects of running ("runner's high") are unknown. Leptin receptor (LepR) signaling involves activation of signal transducer and activator of transcription-3 (STAT3), including in dopamine neurons of the ventral tegmental area (VTA) that are essential for reward-relevant behavior. We found that mice lacking STAT3 in dopamine neurons exhibit greater voluntary running, an effect reversed by viral-mediated STAT3 restoration. STAT3 deletion increased the rewarding effects of running whereas intra-VTA leptin blocked it in a STAT3-dependent manner. Finally, STAT3 loss-of-function reduced mesolimbic dopamine overflow and function. Findings suggest that leptin influences the motivational effects of running via LepR-STAT3 modulation of dopamine tone. Falling leptin is hypothesized to increase stamina and the rewarding effects of running as an adaptive means to enhance the pursuit and procurement of food.
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Affiliation(s)
- Maria Fernanda A Fernandes
- Centre de Recherche du CHUM and Montreal Diabetes Research Center, Université de Montreal, QC H2X 0A9, Canada; Department of Physiology, Université de Montreal, QC H2X 0A9, Canada
| | - Dominique Matthys
- Centre de Recherche du CHUM and Montreal Diabetes Research Center, Université de Montreal, QC H2X 0A9, Canada; Department of Neuroscience, Université de Montreal, QC H2X 0A9, Canada
| | - Cécile Hryhorczuk
- Centre de Recherche du CHUM and Montreal Diabetes Research Center, Université de Montreal, QC H2X 0A9, Canada; Department of Physiology, Université de Montreal, QC H2X 0A9, Canada
| | - Sandeep Sharma
- Centre de Recherche du CHUM and Montreal Diabetes Research Center, Université de Montreal, QC H2X 0A9, Canada; Department of Nutrition, Université de Montreal, QC H2X 0A9, Canada
| | - Shabana Mogra
- Centre de Recherche du CHUM and Montreal Diabetes Research Center, Université de Montreal, QC H2X 0A9, Canada
| | - Thierry Alquier
- Centre de Recherche du CHUM and Montreal Diabetes Research Center, Université de Montreal, QC H2X 0A9, Canada; Department of Medicine, Université de Montreal, QC H2X 0A9, Canada
| | - Stephanie Fulton
- Centre de Recherche du CHUM and Montreal Diabetes Research Center, Université de Montreal, QC H2X 0A9, Canada; Department of Nutrition, Université de Montreal, QC H2X 0A9, Canada; Center for Studies in Behavioral Neurobiology, Concordia University, Montreal, QC H4B 1R6, Canada.
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Heyse NC, Brenes JC, Schwarting RK. Exercise reward induces appetitive 50-kHz calls in rats. Physiol Behav 2015; 147:131-40. [DOI: 10.1016/j.physbeh.2015.04.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Revised: 04/08/2015] [Accepted: 04/10/2015] [Indexed: 01/14/2023]
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Obici S, Magrisso IJ, Ghazarian AS, Shirazian A, Miller JR, Loyd CM, Begg DP, Krawczewski Carhuatanta KA, Haas MK, Davis JF, Woods SC, Sandoval DA, Seeley RJ, Goodyear LJ, Pothos EN, Mul JD. Moderate voluntary exercise attenuates the metabolic syndrome in melanocortin-4 receptor-deficient rats showing central dopaminergic dysregulation. Mol Metab 2015; 4:692-705. [PMID: 26500841 PMCID: PMC4588435 DOI: 10.1016/j.molmet.2015.07.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 07/07/2015] [Accepted: 07/09/2015] [Indexed: 01/12/2023] Open
Abstract
Objective Melanocortin-4 receptors (MC4Rs) are highly expressed by dopamine-secreting neurons of the mesolimbic tract, but their functional role has not been fully resolved. Voluntary wheel running (VWR) induces adaptations in the mesolimbic dopamine system and has a myriad of long-term beneficial effects on health. In the present experiments we asked whether MC4R function regulates the effects of VWR, and whether VWR ameliorates MC4R-associated symptoms of the metabolic syndrome. Methods Electrically evoked dopamine release was measured in slice preparations from sedentary wild-type and MC4R-deficient Mc4rK314X (HOM) rats. VWR was assessed in wild-type and HOM rats, and in MC4R-deficient loxTBMc4r mice, wild-type mice body weight-matched to loxTBMc4r mice, and wild-type mice with intracerebroventricular administration of the MC4R antagonist SHU9119. Mesolimbic dopamine system function (gene/protein expression) and metabolic parameters were examined in wheel-running and sedentary wild-type and HOM rats. Results Sedentary obese HOM rats had increased electrically evoked dopamine release in several ventral tegmental area (VTA) projection sites compared to wild-type controls. MC4R loss-of-function decreased VWR, and this was partially independent of body weight. HOM wheel-runners had attenuated markers of intracellular D1-type dopamine receptor signaling despite increased dopamine flux in the VTA. VWR increased and decreased ΔFosB levels in the nucleus accumbens (NAc) of wild-type and HOM runners, respectively. VWR improved metabolic parameters in wild-type wheel-runners. Finally, moderate voluntary exercise corrected many aspects of the metabolic syndrome in HOM runners. Conclusions Central dopamine dysregulation during VWR reinforces the link between MC4R function and molecular and behavioral responding to rewards. The data also suggest that exercise can be a successful lifestyle intervention in MC4R-haploinsufficient individuals despite reduced positive reinforcement during exercise training. MC4R-deficiency causes metabolic syndrome. Loss of MC4R signaling decreases voluntary wheel running (VWR). Despite moderate amounts of VWR, MC4R-associated metabolic syndrome is severely attenuated. MC4R-deficiency is associated with mesolimbic dopamine dysregulation during VWR.
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Affiliation(s)
- Silvana Obici
- Metabolic Diseases Institute, University of Cincinnati, Cincinnati, OH, USA
| | - I Jack Magrisso
- Metabolic Diseases Institute, University of Cincinnati, Cincinnati, OH, USA
| | - Armen S Ghazarian
- Programs in Pharmacology and Experimental Therapeutics and Neuroscience, Sackler School of Graduate Biomedical Sciences and Department of Integrative Physiology and Pathobiology, Tufts University School of Medicine, Boston, MA, USA
| | - Alireza Shirazian
- Programs in Pharmacology and Experimental Therapeutics and Neuroscience, Sackler School of Graduate Biomedical Sciences and Department of Integrative Physiology and Pathobiology, Tufts University School of Medicine, Boston, MA, USA
| | - Jonas R Miller
- Programs in Pharmacology and Experimental Therapeutics and Neuroscience, Sackler School of Graduate Biomedical Sciences and Department of Integrative Physiology and Pathobiology, Tufts University School of Medicine, Boston, MA, USA
| | - Christine M Loyd
- Metabolic Diseases Institute, University of Cincinnati, Cincinnati, OH, USA
| | - Denovan P Begg
- Metabolic Diseases Institute, University of Cincinnati, Cincinnati, OH, USA ; School of Psychology, UNSW Australia, Sydney, NSW, Australia
| | | | - Michael K Haas
- Metabolic Diseases Institute, University of Cincinnati, Cincinnati, OH, USA
| | - Jon F Davis
- Metabolic Diseases Institute, University of Cincinnati, Cincinnati, OH, USA
| | - Stephen C Woods
- Metabolic Diseases Institute, University of Cincinnati, Cincinnati, OH, USA
| | - Darleen A Sandoval
- North Campus Research Complex, Department of Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Randy J Seeley
- North Campus Research Complex, Department of Surgery, University of Michigan, Ann Arbor, MI, USA
| | | | - Emmanuel N Pothos
- Programs in Pharmacology and Experimental Therapeutics and Neuroscience, Sackler School of Graduate Biomedical Sciences and Department of Integrative Physiology and Pathobiology, Tufts University School of Medicine, Boston, MA, USA
| | - Joram D Mul
- Metabolic Diseases Institute, University of Cincinnati, Cincinnati, OH, USA ; Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA
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Piza-Palma C, Barfield ET, Brown JA, Hubka JC, Lusk C, Schonhar CA, Sweat SC, Grisel JE. Oral self-administration of EtOH: sex-dependent modulation by running wheel access in C57BL/6J mice. Alcohol Clin Exp Res 2015; 38:2387-95. [PMID: 25257288 DOI: 10.1111/acer.12519] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2013] [Accepted: 06/14/2014] [Indexed: 12/18/2022]
Abstract
BACKGROUND The effects of stress, including neuroendocrine and behavioral sequelae aimed at maintaining homeostasis, are associated with increased alcohol consumption. Because both stress and drinking are multifactorial, the mechanisms underlying the relationship are difficult to elucidate. We therefore employed an animal model investigating the influence of blocked access to a running wheel on drinking in C57BL/6J (B6) mice. METHODS In the first experiment, naïve, adult male and female subjects were individually housed for 2 weeks with 24-hour access to a running wheel and 12% ethanol (EtOH) in a 2-bottle, free choice paradigm. After determining baseline consumption and preference, experimental subjects had the running wheel placed in a locked position for 6 hours, and the EtOH bottle was removed during the first half of this period. Two subsequent experiments, again in adult, naïve B6 mice, examined the influence of locked running wheels on self-administration of 20% EtOH in a limited access paradigm, and blood EtOH concentrations (BECs) were determined on the final day of this protocol. RESULTS In all 3 studies, using both between- and within-subject analyses, females showed transient yet reliable increases in alcohol drinking during blocked access to a rotating activity, while drinking in male mice was largely insensitive to this manipulation, although both sexes showed appreciable BECs (>130 mg/dl in females and 80 mg/dl in males) following a 2-hour EtOH access period. CONCLUSIONS These data add to a burgeoning literature suggesting that the factors contributing to excessive alcohol use differ between males and females and that females may be especially sensitive to the influence of wheel manipulation. Elucidating the sex-dependent mechanisms mediating differences in alcohol sensitivity and response is critical to understanding the causes of alcoholism and in developing effective treatments and interventions.
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Cunha FDS, Dalle Molle R, Portella AK, Benetti CDS, Noschang C, Goldani MZ, Silveira PP. Both food restriction and high-fat diet during gestation induce low birth weight and altered physical activity in adult rat offspring: the "Similarities in the Inequalities" model. PLoS One 2015; 10:e0118586. [PMID: 25738800 PMCID: PMC4349804 DOI: 10.1371/journal.pone.0118586] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 01/20/2015] [Indexed: 11/18/2022] Open
Abstract
We have previously described a theoretical model in humans, called "Similarities in the Inequalities", in which extremely unequal social backgrounds coexist in a complex scenario promoting similar health outcomes in adulthood. Based on the potential applicability of and to further explore the "similarities in the inequalities" phenomenon, this study used a rat model to investigate the effect of different nutritional backgrounds during gestation on the willingness of offspring to engage in physical activity in adulthood. Sprague-Dawley rats were time mated and randomly allocated to one of three dietary groups: Control (Adlib), receiving standard laboratory chow ad libitum; 50% food restricted (FR), receiving 50% of the ad libitum-fed dam's habitual intake; or high-fat diet (HF), receiving a diet containing 23% fat. The diets were provided from day 10 of pregnancy until weaning. Within 24 hours of birth, pups were cross-fostered to other dams, forming the following groups: Adlib_Adlib, FR_Adlib, and HF_Adlib. Maternal chow consumption and weight gain, and offspring birth weight, growth, physical activity (one week of free exercise in running wheels), abdominal adiposity and biochemical data were evaluated. Western blot was performed to assess D2 receptors in the dorsal striatum. The "similarities in the inequalities" effect was observed on birth weight (both FR and HF groups were smaller than the Adlib group at birth) and physical activity (both FR_Adlib and HF_Adlib groups were different from the Adlib_Adlib group, with less active males and more active females). Our findings contribute to the view that health inequalities in fetal life may program the health outcomes manifested in offspring adult life (such as altered physical activity and metabolic parameters), probably through different biological mechanisms.
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Affiliation(s)
- Fábio da Silva Cunha
- Programa de Pós-Graduação da Saúde da Criança e do Adolescente, Departamento de Pediatria, Faculdade de Medicina, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Roberta Dalle Molle
- Programa de Pós-Graduação da Saúde da Criança e do Adolescente, Departamento de Pediatria, Faculdade de Medicina, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - André Krumel Portella
- Departamento de Pediatria, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Carla da Silva Benetti
- Programa de Pós-Graduação da Saúde da Criança e do Adolescente, Departamento de Pediatria, Faculdade de Medicina, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Cristie Noschang
- Programa de Pós-Graduação da Saúde da Criança e do Adolescente, Departamento de Pediatria, Faculdade de Medicina, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Marcelo Zubaran Goldani
- Programa de Pós-Graduação da Saúde da Criança e do Adolescente, Departamento de Pediatria, Faculdade de Medicina, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Patrícia Pelufo Silveira
- Programa de Pós-Graduação da Saúde da Criança e do Adolescente, Departamento de Pediatria, Faculdade de Medicina, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
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Abstract
Here we summarize topics covered in an SFN symposium that considered how and why exercise and energy intake affect neuroplasticity and, conversely, how the brain regulates peripheral energy metabolism. This article is not a comprehensive review of the subject, but rather a view of how the authors' findings fit into a broader context. Emerging findings elucidate cellular and molecular mechanisms by which exercise and energy intake modify the plasticity of neural circuits in ways that affect brain health. By enhancing neurogenesis, synaptic plasticity and neuronal stress robustness, exercise and intermittent energy restriction/fasting may optimize brain function and forestall metabolic and neurodegenerative diseases. Moreover, brain-centered glucoregulatory and immunomodulating systems that mediate peripheral health benefits of intermittent energetic challenges have recently been described. A better understanding of adaptive neural response pathways activated by energetic challenges will enable the development and optimization of interventions to reduce the burden of disease in our communities.
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Trost A, Hauber W. Dopamine D1/D2 receptors do not mediate the expression of conditioned place preference induced by the aftereffect of wheel running. BMC Neurosci 2014; 15:124. [PMID: 25407014 PMCID: PMC4239394 DOI: 10.1186/s12868-014-0124-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 10/30/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Rats lever-press for access to running wheels suggesting that wheel running by itself is reinforcing. Furthermore, pairings of an episode of wheel running and subsequent confinement in a specific environment can establish a conditioned place preference (CPP). This finding implies that the reinforcing effects of wheel running outlast the actual occurrence of physical activity, a phenomenon referred to as aftereffect of wheel running. Aftereffect-induced CPP involves Pavlovian conditioning, i.e. repeated pairings of the aftereffect of wheel running with a specific environment creates a learned association between aftereffect and environment and, in turn, a preference for that environment. Given the involvement of dopamine systems in mediating effects of Pavlovian stimuli on appetitive behavior, a role of dopamine in mediating aftereffect-induced CPP seems plausible. Here we assessed whether the mixed D1/D2 receptor antagonist flupenthixol (0.25 mg/kg, i.p.) can block the expression of an aftereffect-induced CPP. RESULTS In line with earlier studies, our results demonstrate that rats displayed a conditioned preference for environments paired with the aftereffect of wheel running and further show that the magnitude of CPP was not related to the wheel running rate. Furthermore, we found that flupenthixol (0.25 mg/kg, i.p.) reduced locomotor activity but did not attenuate the expression of an aftereffect-induced CPP. CONCLUSION The expression of a CPP produced by the aftereffect of wheel running seems not to depend on dopamine D1/D2 receptor activation.
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Affiliation(s)
| | - Wolfgang Hauber
- Department Animal Physiology, University of Stuttgart, Pfaffenwaldring 57, Stuttgart, D-70550, Germany.
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Gallego X, Cox RJ, Funk E, Foster RA, Ehringer MA. Voluntary exercise decreases ethanol preference and consumption in C57BL/6 adolescent mice: sex differences and hippocampal BDNF expression. Physiol Behav 2014; 138:28-36. [PMID: 25447477 DOI: 10.1016/j.physbeh.2014.10.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 06/24/2014] [Accepted: 10/09/2014] [Indexed: 12/13/2022]
Abstract
Adolescence is a period of high vulnerability for alcohol use and abuse. Early alcohol use has been shown to increase the risk for alcohol-related problems later in life; therefore effective preventive treatments targeted toward adolescents would be very valuable. Many epidemiological and longitudinal studies in humans have revealed the beneficial effects of exercise for prevention and treatment of alcohol addiction. Pre-clinical studies have demonstrated that access to a running wheel leads to decreased voluntary alcohol consumption in adult mice, hamsters, and rats. However, age and sex may also influence the effects of exercise on alcohol use. Herein, we studied male and female C57BL/6 adolescent mice using a 24-hour two-bottle choice paradigm to evaluate 21 days of concurrent voluntary exercise on alcohol consumption and preference. Given previously known effects of exercise in increasing the expression of brain-derived neurotrophic factor (BDNF) in the hippocampus and its role in regulating the reward system, BDNF mRNA and protein levels were measured at the end of the behavioral experiment. Our results demonstrate sex differences in the efficacy of voluntary exercise and its effects on decreasing alcohol consumption and preference. We also report increased BDNF expression after 21 days of voluntary exercise in both male and female mice. Interestingly, the distance traveled played an important role in alcohol consumption and preference in female mice but not in male mice. Overall, this study demonstrates sex differences in the effects of voluntary exercise on alcohol consumption in adolescent mice and points out the importance of distance traveled as a limiting factor to the beneficial effects of wheel running in female mice.
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Affiliation(s)
- X Gallego
- Institute for Behavioral Genetics, University of Colorado Boulder, CO 80303, USA
| | - R J Cox
- Institute for Behavioral Genetics, University of Colorado Boulder, CO 80303, USA
| | - E Funk
- Institute for Behavioral Genetics, University of Colorado Boulder, CO 80303, USA
| | - R A Foster
- Institute for Behavioral Genetics, University of Colorado Boulder, CO 80303, USA
| | - M A Ehringer
- Institute for Behavioral Genetics, University of Colorado Boulder, CO 80303, USA; Department of Integrative Physiology, University of Colorado Boulder, CO 80303, USA.
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