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Szabó P, Bonet S, Hetényi R, Hanna D, Kovács Z, Prisztóka G, Križalkovičová Z, Szentpéteri J. Systematic review: pain, cognition, and cardioprotection-unpacking oxytocin's contributions in a sport context. Front Physiol 2024; 15:1393497. [PMID: 38915776 PMCID: PMC11194439 DOI: 10.3389/fphys.2024.1393497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Accepted: 05/13/2024] [Indexed: 06/26/2024] Open
Abstract
Introduction This systematic review investigates the interplay between oxytocin and exercise; in terms of analgesic, anti-inflammatory, pro-regenerative, and cardioprotective effects. Furthermore, by analyzing measurement methods, we aim to improve measurement validity and reliability. Methods Utilizing PRISMA, GRADE, and MECIR protocols, we examined five databases with a modified SPIDER search. Including studies on healthy participants, published within the last 20 years, based on keywords "oxytocin," "exercise" and "measurement," 690 studies were retrieved initially (455 unique records). After excluding studies of clinically identifiable diseases, and unpublished and reproduction-focused studies, 175 studies qualified for the narrative cross-thematic and structural analysis. Results The analysis resulted in five categories showing the reciprocal impact of oxytocin and exercise: Exercise (50), Physiology (63), Environment (27), Social Context (65), and Stress (49). Exercise-induced oxytocin could promote tissue regeneration, with 32 studies showing its analgesic and anti-inflammatory effects, while 14 studies discussed memory and cognition. Furthermore, empathy-associated OXTR rs53576 polymorphism might influence team sports performance. Since dietary habits and substance abuse can impact oxytocin secretion too, combining self-report tests and repeated salivary measurements may help achieve precision. Discussion Oxytocin's effect on fear extinction and social cognition might generate strategies for mental training, and technical, and tactical development in sports. Exercise-induced oxytocin can affect the amount of stress experienced by athletes, and their response to it. However, oxytocin levels could depend on the type of sport in means of contact level, exercise intensity, and duration. The influence of oxytocin on athletes' performance and recovery could have been exploited due to its short half-life. Examining oxytocin's complex interactions with exercise paves the way for future research and application in sports science, psychology, and medical disciplines. Systematic Review Registration https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=512184, identifier CRD42024512184.
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Affiliation(s)
- Péter Szabó
- Faculty of Sciences, Institute of Sports Science and Physical Education, University of Pécs, Pécs, Hungary
- Faculty of Humanities, University of Pécs, Pécs, Hungary
- Medical School, Institute of Transdisciplinary Discoveries, University of Pécs, Pécs, Hungary
| | - Sara Bonet
- Faculty of Medicine Osijek, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia
| | - Roland Hetényi
- RoLink Biotechnology Kft., Pécs, Hungary
- Hungarian National Blood Transfusion Service, Budapest, Hungary
- Szentágothai Research Centre, University of Pécs, Pécs, Hungary
- National Virology Laboratory, University of Pécs, Pécs, Hungary
| | - Dániel Hanna
- RoLink Biotechnology Kft., Pécs, Hungary
- Hungarian National Blood Transfusion Service, Budapest, Hungary
- Szentágothai Research Centre, University of Pécs, Pécs, Hungary
- National Virology Laboratory, University of Pécs, Pécs, Hungary
| | - Zsófia Kovács
- Faculty of Sciences, Institute of Sports Science and Physical Education, University of Pécs, Pécs, Hungary
| | - Gyöngyvér Prisztóka
- Faculty of Sciences, Institute of Sports Science and Physical Education, University of Pécs, Pécs, Hungary
| | - Zuzana Križalkovičová
- Faculty of Health Sciences, Institute of Physiotherapy and Sport Science, Department of Sport Science, Pécs, Hungary
| | - József Szentpéteri
- Medical School, Institute of Transdisciplinary Discoveries, University of Pécs, Pécs, Hungary
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Flores MR, Zuniga SS. Integration of Endogenous Opioid System Research in the Interprofessional Diagnosis and Treatment of Obesity and Eating Disorders. ADVANCES IN NEUROBIOLOGY 2024; 35:357-380. [PMID: 38874732 DOI: 10.1007/978-3-031-45493-6_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2024]
Abstract
This third and final chapter in our trilogy introduces the clinical distinctions and phenotypical similarities between obesity and eating disorders. Research elaborating on the shared neurobiological substrates for obesity and eating disorders is discussed. We present an interprofessional model of treatment for both disordered eating and for obesity. Additionally, this chapter establishes the translational importance of research connecting endogenous opioid activity with both obesity and eating disorders, with an emphasis on clinical interventions. We conclude with a discussion of future directions for research.
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Affiliation(s)
| | - Sylvana Stephano Zuniga
- Obesity and Eating Disorders Clinic, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, Mexico
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Al‐Alsheikh AS, Alabdulkader S, Miras AD, Goldstone AP. Effects of bariatric surgery and dietary interventions for obesity on brain neurotransmitter systems and metabolism: A systematic review of positron emission tomography (PET) and single-photon emission computed tomography (SPECT) studies. Obes Rev 2023; 24:e13620. [PMID: 37699864 PMCID: PMC10909448 DOI: 10.1111/obr.13620] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 04/05/2023] [Accepted: 07/10/2023] [Indexed: 09/14/2023]
Abstract
This systematic review collates studies of dietary or bariatric surgery interventions for obesity using positron emission tomography and single-photon emission computed tomography. Of 604 publications identified, 22 met inclusion criteria. Twelve studies assessed bariatric surgery (seven gastric bypass, five gastric bypass/sleeve gastrectomy), and ten dietary interventions (six low-calorie diet, three very low-calorie diet, one prolonged fasting). Thirteen studies examined neurotransmitter systems (six used tracers for dopamine DRD2/3 receptors: two each for 11 C-raclopride, 18 F-fallypride, 123 I-IBZM; one for dopamine transporter, 123 I-FP-CIT; one used tracer for serotonin 5-HT2A receptor, 18 F-altanserin; two used tracers for serotonin transporter, 11 C-DASB or 123 I-FP-CIT; two used tracer for μ-opioid receptor, 11 C-carfentanil; one used tracer for noradrenaline transporter, 11 C-MRB); seven studies assessed glucose uptake using 18 F-fluorodeoxyglucose; four studies assessed regional cerebral blood flow using 15 O-H2 O (one study also used arterial spin labeling); and two studies measured fatty acid uptake using 18 F-FTHA and one using 11 C-palmitate. The review summarizes findings and correlations with clinical outcomes, eating behavior, and mechanistic mediators. The small number of studies using each tracer and intervention, lack of dietary intervention control groups in any surgical studies, heterogeneity in time since intervention and degree of weight loss, and small sample sizes hindered the drawing of robust conclusions across studies.
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Affiliation(s)
- Alhanouf S. Al‐Alsheikh
- Department of Metabolism, Digestion and Reproduction, Imperial College LondonHammersmith HospitalLondonUK
- Department of Community Health Sciences, College of Applied Medical SciencesKing Saud UniversityRiyadhSaudi Arabia
| | - Shahd Alabdulkader
- Department of Metabolism, Digestion and Reproduction, Imperial College LondonHammersmith HospitalLondonUK
- Department of Health Sciences, College of Health and Rehabilitation SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia
| | - Alexander D. Miras
- Department of Metabolism, Digestion and Reproduction, Imperial College LondonHammersmith HospitalLondonUK
- School of Medicine, Faculty of Life and Health SciencesUlster UniversityLondonderryUK
| | - Anthony P. Goldstone
- PsychoNeuroEndocrinology Research Group, Division of Psychiatry, Department of Brain Sciences, Imperial College LondonHammersmith HospitalLondonUK
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4
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Rolls ET. Emotion, motivation, decision-making, the orbitofrontal cortex, anterior cingulate cortex, and the amygdala. Brain Struct Funct 2023:10.1007/s00429-023-02644-9. [PMID: 37178232 DOI: 10.1007/s00429-023-02644-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 04/12/2023] [Indexed: 05/15/2023]
Abstract
The orbitofrontal cortex and amygdala are involved in emotion and in motivation, but the relationship between these functions performed by these brain structures is not clear. To address this, a unified theory of emotion and motivation is described in which motivational states are states in which instrumental goal-directed actions are performed to obtain rewards or avoid punishers, and emotional states are states that are elicited when the reward or punisher is or is not received. This greatly simplifies our understanding of emotion and motivation, for the same set of genes and associated brain systems can define the primary or unlearned rewards and punishers such as sweet taste or pain. Recent evidence on the connectivity of human brain systems involved in emotion and motivation indicates that the orbitofrontal cortex is involved in reward value and experienced emotion with outputs to cortical regions including those involved in language, and is a key brain region involved in depression and the associated changes in motivation. The amygdala has weak effective connectivity back to the cortex in humans, and is implicated in brainstem-mediated responses to stimuli such as freezing and autonomic activity, rather than in declarative emotion. The anterior cingulate cortex is involved in learning actions to obtain rewards, and with the orbitofrontal cortex and ventromedial prefrontal cortex in providing the goals for navigation and in reward-related effects on memory consolidation mediated partly via the cholinergic system.
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Affiliation(s)
- Edmund T Rolls
- Oxford Centre for Computational Neuroscience, Oxford, UK.
- Department of Computer Science, University of Warwick, Coventry, UK.
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5
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Iqbal A, Hamid A, Ahmad SM, Lutfy K. The Role of Mu Opioid Receptors in High Fat Diet-Induced Reward and Potentiation of the Rewarding Effect of Oxycodone. Life (Basel) 2023; 13:life13030619. [PMID: 36983775 PMCID: PMC10055773 DOI: 10.3390/life13030619] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 02/16/2023] [Accepted: 02/20/2023] [Indexed: 02/25/2023] Open
Abstract
Excessive high fat diet (HFD) consumption can induce food addiction, which is believed to involve the communication between the hypothalamus and mesolimbic dopaminergic neurons, originating in the ventral tegmental area (VTA) and projecting to the nucleus accumbens (NAc). These brain areas are densely populated with opioid receptors, raising the possibility that these receptors, and particularly mu opioid receptors (MORs), are involved in rewards elicited by palatable food. This study sought to investigate the involvement of MORs in HFD-induced reward and if there is any difference between male and female subjects in this response. We also assessed if exposure to HFD would alter the rewarding action of oxycodone, a relatively selective MOR agonist. The place conditioning paradigm was used as an animal model of reward to determine if short-time (STC, 2 h) or long-time (LTC, 16 h) conditioning with HFD induces reward or alters the rewarding action of oxycodone. Male and female C57BL/6J mice as well as MOR knockout and their wildtype littermates of both sexes were tested for basal place preference on day 1 and then conditioned with an HFD in one chamber and a regular chow diet (RCD) in another chamber for 2 h on alternate days. Three sets of STC were used, followed by a set of LTC. Each set of conditioning consisted of two conditioning with RCD and two conditioning with HFD. Mice were tested for place preference after each set of STC and again after LTC. Controls were conditioned with RCD in both conditioning chambers. Following the last place preference test, mice were treated with oxycodone and conditioned in the HFD-paired chamber and with saline in the RCD-paired chamber for one hour once a day to explore the possibility if the HFD could alter oxycodone reward. The result showed that HFD induced conditioned place preference (CPP) in male but not female subjects. However, oxycodone conditioning elicited reward in both male and female mice of the HFD group but not the control group, showing that prior conditioning with HFD potentiated the rewarding action of oxycodone. The latter response was mediated via MORs, as it was blunted in MOR knockout mice. Similarly, HFD-induced CPP was blunted in male MOR knockout mice, suggesting sexual dimorphism in this response.
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Wang Y, Zhuang Y, DiBerto JF, Zhou XE, Schmitz GP, Yuan Q, Jain MK, Liu W, Melcher K, Jiang Y, Roth BL, Xu HE. Structures of the entire human opioid receptor family. Cell 2023; 186:413-427.e17. [PMID: 36638794 DOI: 10.1016/j.cell.2022.12.026] [Citation(s) in RCA: 34] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 10/11/2022] [Accepted: 12/13/2022] [Indexed: 01/13/2023]
Abstract
Opioids are effective analgesics, but their use is beset by serious side effects, including addiction and respiratory depression, which contribute to the ongoing opioid crisis. The human opioid system contains four opioid receptors (μOR, δOR, κOR, and NOPR) and a set of related endogenous opioid peptides (EOPs), which show distinct selectivity toward their respective opioid receptors (ORs). Despite being key to the development of safer analgesics, the mechanisms of molecular recognition and selectivity of EOPs to ORs remain unclear. Here, we systematically characterize the binding of EOPs to ORs and present five structures of EOP-OR-Gi complexes, including β-endorphin- and endomorphin-bound μOR, deltorphin-bound δOR, dynorphin-bound κOR, and nociceptin-bound NOPR. These structures, supported by biochemical results, uncover the specific recognition and selectivity of opioid peptides and the conserved mechanism of opioid receptor activation. These results provide a structural framework to facilitate rational design of safer opioid drugs for pain relief.
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Affiliation(s)
- Yue Wang
- The CAS Key Laboratory of Receptor Research and the State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Youwen Zhuang
- The CAS Key Laboratory of Receptor Research and the State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
| | - Jeffrey F DiBerto
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA
| | - X Edward Zhou
- Department of Structural Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | - Gavin P Schmitz
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA
| | - Qingning Yuan
- The CAS Key Laboratory of Receptor Research and the State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; The Shanghai Advanced Electron Microscope Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Manish K Jain
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA
| | - Weiyi Liu
- The CAS Key Laboratory of Receptor Research and the State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Karsten Melcher
- Department of Structural Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | - Yi Jiang
- The CAS Key Laboratory of Receptor Research and the State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; Lingang Laboratory, Shanghai 200031, China
| | - Bryan L Roth
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA.
| | - H Eric Xu
- The CAS Key Laboratory of Receptor Research and the State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; University of Chinese Academy of Sciences, Beijing 100049, China; School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.
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7
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Jaime-Lara RB, Brooks BE, Vizioli C, Chiles M, Nawal N, Ortiz-Figueroa RSE, Livinski AA, Agarwal K, Colina-Prisco C, Iannarino N, Hilmi A, Tejeda HA, Joseph PV. A systematic review of the biological mediators of fat taste and smell. Physiol Rev 2023; 103:855-918. [PMID: 36409650 PMCID: PMC9678415 DOI: 10.1152/physrev.00061.2021] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Taste and smell play a key role in our ability to perceive foods. Overconsumption of highly palatable energy-dense foods can lead to increased caloric intake and obesity. Thus there is growing interest in the study of the biological mediators of fat taste and associated olfaction as potential targets for pharmacologic and nutritional interventions in the context of obesity and health. The number of studies examining mechanisms underlying fat taste and smell has grown rapidly in the last 5 years. Therefore, the purpose of this systematic review is to summarize emerging evidence examining the biological mechanisms of fat taste and smell. A literature search was conducted of studies published in English between 2014 and 2021 in adult humans and animal models. Database searches were conducted using PubMed, EMBASE, Scopus, and Web of Science for key terms including fat/lipid, taste, and olfaction. Initially, 4,062 articles were identified through database searches, and a total of 84 relevant articles met inclusion and exclusion criteria and are included in this review. Existing literature suggests that there are several proteins integral to fat chemosensation, including cluster of differentiation 36 (CD36) and G protein-coupled receptor 120 (GPR120). This systematic review will discuss these proteins and the signal transduction pathways involved in fat detection. We also review neural circuits, key brain regions, ingestive cues, postingestive signals, and genetic polymorphism that play a role in fat perception and consumption. Finally, we discuss the role of fat taste and smell in the context of eating behavior and obesity.
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Affiliation(s)
- Rosario B. Jaime-Lara
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Brianna E. Brooks
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Carlotta Vizioli
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Mari Chiles
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland,4Section of Neuromodulation and Synaptic Integration, Division of Intramural Research, National Institute of Mental Health, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Nafisa Nawal
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Rodrigo S. E. Ortiz-Figueroa
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Alicia A. Livinski
- 3NIH Library, Office of Research Services, Office of the Director, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Khushbu Agarwal
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Claudia Colina-Prisco
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Natalia Iannarino
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Aliya Hilmi
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Hugo A. Tejeda
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Paule V. Joseph
- 1Section of Sensory Science and Metabolism Unit, Division of Intramural Research, National Institutes of Health, National Institute of Alcohol Abuse and Alcoholism, U.S. Department of Health and Human Services, Bethesda, Maryland,2Section of Sensory Science and Metabolism, Division of Intramural Research, National Institute of Nursing Research, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland
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8
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Behavioral Reaction and c-fos Expression after Opioids Injection into the Pedunculopontine Tegmental Nucleus and Electrical Stimulation of the Ventral Tegmental Area. Int J Mol Sci 2022; 24:ijms24010512. [PMID: 36613953 PMCID: PMC9820701 DOI: 10.3390/ijms24010512] [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: 11/21/2022] [Revised: 12/18/2022] [Accepted: 12/22/2022] [Indexed: 12/29/2022] Open
Abstract
The pedunculopontine tegmental nucleus (PPN) regulates the activity of dopaminergic cells in the ventral tegmental area (VTA). In this study, the role of opioid receptors (OR) in the PPN on motivated behaviors was investigated by using a model of feeding induced by electrical VTA-stimulation (Es-VTA) in rats (male Wistar; n = 91). We found that the OR excitation by morphine and their blocking by naloxone within the PPN caused a change in the analyzed motivational behavior and neuronal activation. The opioid injections into the PPN resulted in a marked, dose-dependent increase/decrease in latency to feeding response (FR), which corresponded with increased neuronal activity (c-Fos protein), in most of the analyzed brain structures. Morphine dosed at 1.25/1.5 µg into the PPN significantly reduced behavior induced by Es-VTA, whereas morphine dosed at 0.25/0.5 µg into the PPN did not affect this behavior. The opposite effect was observed after the naloxone injection into the PPN, where its lowest doses of 2.5/5.0 μg shortened the FR latency. However, its highest dose of 25.0 μg into the PPN nucleus did not cause FR latency changes. In conclusion, the level of OR arousal in the PPN can modulate the activity of the reward system.
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Pekkarinen L, Kantonen T, Rebelos E, Latva-Rasku A, Dadson P, Karjalainen T, Bucci M, Kalliokoski K, Laitinen K, Houttu N, Kirjavainen AK, Rajander J, Rönnemaa T, Nummenmaa L, Nuutila P. Obesity risk is associated with brain glucose uptake and insulin resistance. Eur J Endocrinol 2022; 187:917-928. [PMID: 36288097 PMCID: PMC9782452 DOI: 10.1530/eje-22-0509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 10/26/2022] [Indexed: 01/09/2023]
Abstract
OBJECTIVE To investigate whether alterations in brain glucose uptake (BGU), insulin action in the brain-liver axis and whole-body insulin sensitivity occur in young adults in pre-obese state. METHODS Healthy males with either high risk (HR; n = 19) or low risk (LR; n = 22) for developing obesity were studied with [18F]fluoro-d-glucose ([18F]FDG)-positron emission tomography during hyperinsulinemic-euglycemic clamp. Obesity risk was assessed according to BMI, physical activity and parental overweight/obesity and type 2 diabetes. Brain, skeletal muscle, brown adipose tissue (BAT), visceral adipose tissue (VAT) and abdominal and femoral s.c. adipose tissue (SAT) glucose uptake (GU) rates were measured. Endogenous glucose production (EGP) was calculated by subtracting the exogenous glucose infusion rate from the rate of disappearance of [18F]FDG. BGU was analyzed using statistical parametric mapping, and peripheral tissue activity was determined using Carimas Software imaging processing platform. RESULTS BGU was higher in the HR vs LR group and correlated inversely with whole-body insulin sensitivity (M value) in the HR group but not in the LR group. Insulin-suppressed EGP did not differ between the groups but correlated positively with BGU in the whole population, and the correlation was driven by the HR group. Skeletal muscle, BAT, VAT, abdominal and femoral SAT GU were lower in the HR group as compared to the LR group. Muscle GU correlated negatively with BGU in the HR group but not in the LR group. CONCLUSION Increased BGU, alterations in insulin action in the brain-liver axis and decreased whole-body insulin sensitivity occur early in pre-obese state.
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Affiliation(s)
- Laura Pekkarinen
- Turku PET Centre, University of Turku, Turku, Finland
- Department of Endocrinology, Turku University Hospital, Turku, Finland
| | - Tatu Kantonen
- Turku PET Centre, University of Turku, Turku, Finland
- Clinical Neurosciences, Turku University Hospital, Turku, Finland
| | - Eleni Rebelos
- Turku PET Centre, University of Turku, Turku, Finland
| | | | - Prince Dadson
- Turku PET Centre, University of Turku, Turku, Finland
| | | | - Marco Bucci
- Turku PET Centre, University of Turku, Turku, Finland
- Turku PET Centre, Åbo Akademi University, Turku, Finland
| | | | - Kirsi Laitinen
- Institute of Biomedicine, Research Centre for Integrative Physiology and Pharmacology, University of Turku, Turku, Finland
| | - Noora Houttu
- Institute of Biomedicine, Research Centre for Integrative Physiology and Pharmacology, University of Turku, Turku, Finland
| | | | - Johan Rajander
- Turku PET Centre, Åbo Akademi University, Turku, Finland
| | - Tapani Rönnemaa
- Department of Endocrinology, Turku University Hospital, Turku, Finland
- Department of Medicine, University of Turku, Turku, Finland
| | - Lauri Nummenmaa
- Turku PET Centre, University of Turku, Turku, Finland
- Department of Psychology, University of Turku, Turku, Finland
| | - Pirjo Nuutila
- Turku PET Centre, University of Turku, Turku, Finland
- Department of Endocrinology, Turku University Hospital, Turku, Finland
- Correspondence should be addressed to P Nuutila;
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10
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Puppala S, Spradling-Reeves KD, Chan J, Birnbaum S, Newman DE, Comuzzie AG, Mahaney MC, VandeBerg JL, Olivier M, Cox LA. Hepatic transcript signatures predict atherosclerotic lesion burden prior to a 2-year high cholesterol, high fat diet challenge. PLoS One 2022; 17:e0271514. [PMID: 35925965 PMCID: PMC9352111 DOI: 10.1371/journal.pone.0271514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 07/04/2022] [Indexed: 11/19/2022] Open
Abstract
The purpose of this study was to identify molecular mechanisms by which the liver influences total lesion burden in a nonhuman primate model (NHP) of cardiovascular disease with acute and chronic feeding of a high cholesterol, high fat (HCHF) diet. Baboons (47 females, 64 males) were fed a HCHF diet for 2 years (y); liver biopsies were collected at baseline, 7 weeks (w) and 2y, and lesions were quantified in aortic arch, descending aorta, and common iliac at 2y. Unbiased weighted gene co-expression network analysis (WGCNA) revealed several modules of hepatic genes correlated with lesions at different time points of dietary challenge. Pathway and network analyses were performed to study the roles of hepatic module genes. More significant pathways were observed in males than females. In males, we found modules enriched for genes in oxidative phosphorylation at baseline, opioid signaling at 7w, and EIF2 signaling and HNF1A and HNF4A networks at baseline and 2y. One module enriched for fatty acid β oxidation pathway genes was found in males and females at 2y. To our knowledge, this is the first study of a large NHP cohort to identify hepatic genes that correlate with lesion burden. Correlations of baseline and 7w module genes with lesions at 2y were observed in males but not in females. Pathway analyses of baseline and 7w module genes indicate EIF2 signaling, oxidative phosphorylation, and μ-opioid signaling are possible mechanisms that predict lesion formation induced by HCHF diet consumption in males. Our findings of coordinated hepatic transcriptional response in male baboons but not female baboons indicate underlying molecular mechanisms differ between female and male primate atherosclerosis.
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Affiliation(s)
- Sobha Puppala
- Center for Precision Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Kimberly D. Spradling-Reeves
- Center for Precision Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Jeannie Chan
- Center for Precision Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Shifra Birnbaum
- Texas Biomedical Research Institute, San Antonio, Texas, United States of America
| | - Deborah E. Newman
- Texas Biomedical Research Institute, San Antonio, Texas, United States of America
| | | | - Michael C. Mahaney
- South Texas Diabetes and Obesity Institute and Department of Human Genetics, The University of Texas Rio Grande Valley School of Medicine, Brownsville, Texas, United States of America
| | - John L. VandeBerg
- South Texas Diabetes and Obesity Institute and Department of Human Genetics, The University of Texas Rio Grande Valley School of Medicine, Brownsville, Texas, United States of America
| | - Michael Olivier
- Center for Precision Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Laura A. Cox
- Center for Precision Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
- Texas Biomedical Research Institute, San Antonio, Texas, United States of America
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11
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Alizadeh S, Djafarian K, Mofidi Nejad M, Yekaninejad MS, Javanbakht MH. The effect of β-caryophyllene on food addiction and its related behaviors: A randomized, double-blind, placebo-controlled trial. Appetite 2022; 178:106160. [PMID: 35809704 DOI: 10.1016/j.appet.2022.106160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 07/03/2022] [Accepted: 07/03/2022] [Indexed: 11/02/2022]
Abstract
Food addiction (FA) is a psychological construct that may be involved in the etiology of obesity. The cannabinoid system is involved in the addictive-like food preferences by acting on the dopaminergic pathway of the brain. β-caryophyllene is a dietary cannabinoid that is a cannabinoid type 2 (CB2) receptor agonist. This study explored the impacts of β-caryophyllene supplementation on eating behavior, appetite, mental health, anthropometric parameters, body composition, and some hormones related to appetite in women with obesity diagnosed with FA. Women with obesity and FA, diagnosed by the Yale Food Addiction Scale Score (YFAS-S) ≥3, were randomly allocated to receive a β-caryophyllene softgel (n = 26) (100 mg/daily with meal) or placebo (n = 26) for 8 weeks. Anthropometric measurements, body composition, eating behavior, biochemical markers, dietary intake, appetite, stress, anxiety, and depression were evaluated during the study period. β-caryophyllene administration significantly reduced YFAS-S compared to the placebo group (changes in FA score: 1.5 ± 0.9 vs. - 0.7 ± 1.4; corrected P = 0.05). Serum levels of orexin-A significantly decreased in the β-caryophyllene group (p = 0.02); however, no significant difference was observed compared to the placebo group (corrected P = 0.09). β-caryophyllene supplementation had no significant effect on body composition, anthropometric indices, appetite, eating behavior, dietary intake, physical activity level, mental health, and levels of oxytocin and neuropeptide Y (NPY), compared to the placebo. β-caryophyllene supplementation may have beneficial effects on improving YFAS-S in women with obesity diagnosed with FA. TRIAL REGISTRATION: Iranian Registry of Clinical Trials identifier: IRCT20200914048712N1.
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Affiliation(s)
- Shahab Alizadeh
- Department of Cellular and Molecular Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Kurosh Djafarian
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Maryam Mofidi Nejad
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Mir Saeed Yekaninejad
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Hassan Javanbakht
- Department of Cellular and Molecular Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
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12
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Brouns F, Shewry PR. Do gluten peptides stimulate weight gain in humans? NUTR BULL 2022; 47:186-198. [PMID: 35915782 PMCID: PMC9328276 DOI: 10.1111/nbu.12558] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 04/05/2022] [Accepted: 04/19/2022] [Indexed: 02/06/2023]
Abstract
Observations from animal and in vitro laboratory research, and anecdotal evidence, have led to the suggestion that gluten consumption stimulates weight gain by the presence of peptides expressing opioid activity. Another proposed mechanism is that gluten peptides decrease resting energy expenditure resulting in a positive energy balance. In order to induce such effects in vivo, intact food peptides must be absorbed in sufficient quantities, remain intact in the blood for sufficient time to have long‐lasting biological activity and bind to receptors involved in appetite, satiety and energy regulation. However, although peptides from food may pass from the intestine into the blood in extremely low quantities, they are generally rapidly degraded by plasma and vasculum‐bound aminopeptidases, resulting in very short half‐lives and loss of bioactivity. At present, gluten peptide sequences that influence regulators of energy metabolism have not been identified. Furthermore, data on the quantitative absorption of gluten peptides in the blood stream, their stability and lasting bioactivity are also lacking. Therefore, there is no evidence for proposed effects on driving appetite by the brain, nor on energy expenditure and weight gain. Furthermore, the level of overweight observed in various countries appears to be independent of the level of wheat consumption, and abundant observational evidence in humans shows that the levels of gluten consumption are neither related to daily calorie intake nor to BMI. This narrative review therefore discusses the proposed effects of gluten on bodyweight (BW) and putative biological mechanisms in the light of the current evidence.
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Affiliation(s)
- Fred Brouns
- School for Nutrition and Translational Research in Metabolism Maastricht University Maastricht The Netherlands
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13
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Psychological pain and opioid receptors: Reward downshift is disrupted when tested in a context signaling morphine. Pharmacol Biochem Behav 2022; 216:173386. [DOI: 10.1016/j.pbb.2022.173386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 03/29/2022] [Accepted: 04/03/2022] [Indexed: 11/22/2022]
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14
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Loss of Corticostriatal Mu-Opioid Receptors in α-Synuclein Transgenic Mouse Brains. LIFE (BASEL, SWITZERLAND) 2022; 12:life12010063. [PMID: 35054456 PMCID: PMC8781165 DOI: 10.3390/life12010063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/28/2021] [Accepted: 12/31/2021] [Indexed: 12/17/2022]
Abstract
Ultrastructural, neurochemical, and molecular alterations within the striatum are associated with the onset and progression of Parkinson’s disease (PD). In PD, the dopamine-containing neurons in the substantia nigra pars compacta (SNc) degenerate and reduce dopamine-containing innervations to the striatum. The loss of striatal dopamine is associated with enhanced corticostriatal glutamatergic plasticity at the early stages of PD. However, with disease progression, the glutamatergic corticostriatal white matter tracts (WMTs) also degenerate. We analyzed the levels of Mu opioid receptors (MORs) in the corticostriatal WMTs, as a function of α-Synuclein (α-Syn) toxicity in transgenic mouse brains. Our data show an age-dependent loss of MOR expression levels in the striatum and specifically, within the caudal striatal WMTs in α-Syn tg mouse brains. The loss of MOR expression is associated with degeneration of the myelinated axons that are localized within the corticostriatal WMTs. In brains affected with late stages of PD, we detect evidence confirming the degeneration of myelinated axons within the corticostriatal WMTs. We conclude that loss of corticostriatal MOR expression is associated with degeneration of corticostriatal WMT in α-Syn tg mice, modeling PD.
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Obesity risk is associated with altered cerebral glucose metabolism and decreased μ-opioid and CB 1 receptor availability. Int J Obes (Lond) 2021; 46:400-407. [PMID: 34728775 PMCID: PMC8794779 DOI: 10.1038/s41366-021-00996-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 07/06/2021] [Accepted: 10/12/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND Obesity is a pressing public health concern worldwide. Novel pharmacological means are urgently needed to combat the increase of obesity and accompanying type 2 diabetes (T2D). Although fully established obesity is associated with neuromolecular alterations and insulin resistance in the brain, potential obesity-promoting mechanisms in the central nervous system have remained elusive. In this triple-tracer positron emission tomography study, we investigated whether brain insulin signaling, μ-opioid receptors (MORs) and cannabinoid CB1 receptors (CB1Rs) are associated with risk for developing obesity. METHODS Subjects were 41 young non-obese males with variable obesity risk profiles. Obesity risk was assessed by subjects' physical exercise habits, body mass index and familial risk factors, including parental obesity and T2D. Brain glucose uptake was quantified with [18F]FDG during hyperinsulinemic euglycemic clamp, MORs were quantified with [11C]carfentanil and CB1Rs with [18F]FMPEP-d2. RESULTS Subjects with higher obesity risk had globally increased insulin-stimulated brain glucose uptake (19 high-risk subjects versus 19 low-risk subjects), and familial obesity risk factors were associated with increased brain glucose uptake (38 subjects) but decreased availability of MORs (41 subjects) and CB1Rs (36 subjects). CONCLUSIONS These results suggest that the hereditary mechanisms promoting obesity may be partly mediated via insulin, opioid and endocannabinoid messaging systems in the brain.
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μ-Opioid Receptor Stimulation in the Nucleus Accumbens Increases Vocal-Social Interactions in Flocking European Starlings, Sturnus Vulgaris. eNeuro 2021; 8:ENEURO.0219-21.2021. [PMID: 34475266 PMCID: PMC8474649 DOI: 10.1523/eneuro.0219-21.2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 08/12/2021] [Accepted: 08/25/2021] [Indexed: 12/14/2022] Open
Abstract
Social connections in gregarious species are vital for safety and survival. For these reasons, many bird species form large flocks outside the breeding season. It has been proposed that such large social groups may be maintained via reward induced by positive interactions with conspecifics and via the reduction of a negative affective state caused by social separation. Moreover, within a flock optimal social spacing between conspecifics is important, indicating that individuals may optimize spacing to be close but not too close to conspecifics. The μ-opioid receptors (MORs) in the nucleus accumbens (NAc) are well known for their role in both reward and the reduction of negative affective states, suggesting that MOR stimulation in NAc may play a critical role in flock cohesion. To begin to test this hypothesis, social and nonsocial behaviors were examined in male and female European starlings (Sturnus vulgaris) in nonbreeding flocks after intra-NAc infusion of saline and three doses of the selective MOR agonist d-Ala2-N-Me-Phe4-Glycol5-enkephalin (DAMGO). DAMGO in NAc dose-dependently increased singing behavior and facilitated social approaches while at the same time promoting displacements potentially used to maintain social spacing. These findings support the hypothesis that MORs in NAc promote social interactions important for group cohesion in nonsexual contexts and suggest the possibility that MORs in the NAc play a role in optimizing the pull of joining a flock with the push of potential agonistic encounters.
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Kantonen T, Karjalainen T, Pekkarinen L, Isojärvi J, Kalliokoski K, Kaasinen V, Hirvonen J, Nuutila P, Nummenmaa L. Cerebral μ-opioid and CB 1 receptor systems have distinct roles in human feeding behavior. Transl Psychiatry 2021; 11:442. [PMID: 34453034 PMCID: PMC8397789 DOI: 10.1038/s41398-021-01559-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 07/26/2021] [Accepted: 08/10/2021] [Indexed: 12/13/2022] Open
Abstract
Eating behavior varies greatly between individuals, but the neurobiological basis of these trait-like differences in feeding remains poorly understood. Central μ-opioid receptors (MOR) and cannabinoid CB1 receptors (CB1R) regulate energy balance via multiple neural pathways, promoting food intake and reward. Because obesity and eating disorders have been associated with alterations in the brain's opioid and endocannabinoid signaling, the variation in MOR and CB1R system function could potentially underlie distinct eating behavior phenotypes. In this retrospective positron emission tomography (PET) study, we analyzed [11C]carfentanil PET scans of MORs from 92 healthy subjects (70 males and 22 females), and [18F]FMPEP-d2 scans of CB1Rs from 35 subjects (all males, all also included in the [11C]carfentanil sample). Eating styles were measured with the Dutch Eating Behavior Questionnaire (DEBQ). We found that lower cerebral MOR availability was associated with increased external eating-individuals with low MORs reported being more likely to eat in response to environment's palatable food cues. CB1R availability was associated with multiple eating behavior traits. We conclude that although MORs and CB1Rs overlap anatomically in brain regions regulating food reward, they have distinct roles in mediating individual feeding patterns. Central MOR system might provide a pharmacological target for reducing individual's excessive cue-reactive eating behavior.
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Affiliation(s)
- Tatu Kantonen
- Turku PET Centre, University of Turku, Turku, Finland. .,Clinical Neurosciences, University of Turku, Turku, Finland.
| | - Tomi Karjalainen
- grid.470895.70000 0004 0391 4481Turku PET Centre, University of Turku, Turku, Finland
| | - Laura Pekkarinen
- grid.470895.70000 0004 0391 4481Turku PET Centre, University of Turku, Turku, Finland ,grid.410552.70000 0004 0628 215XDepartment of Endocrinology, Turku University Hospital, Turku, Finland
| | - Janne Isojärvi
- grid.470895.70000 0004 0391 4481Turku PET Centre, University of Turku, Turku, Finland
| | - Kari Kalliokoski
- grid.470895.70000 0004 0391 4481Turku PET Centre, University of Turku, Turku, Finland
| | - Valtteri Kaasinen
- grid.1374.10000 0001 2097 1371Clinical Neurosciences, University of Turku, Turku, Finland ,grid.410552.70000 0004 0628 215XNeurocenter, Turku University Hospital, Turku, Finland
| | - Jussi Hirvonen
- grid.470895.70000 0004 0391 4481Turku PET Centre, University of Turku, Turku, Finland ,grid.1374.10000 0001 2097 1371Department of Radiology, University of Turku and Turku University Hospital, Turku, Finland
| | - Pirjo Nuutila
- grid.470895.70000 0004 0391 4481Turku PET Centre, University of Turku, Turku, Finland ,grid.410552.70000 0004 0628 215XDepartment of Endocrinology, Turku University Hospital, Turku, Finland
| | - Lauri Nummenmaa
- grid.470895.70000 0004 0391 4481Turku PET Centre, University of Turku, Turku, Finland ,grid.1374.10000 0001 2097 1371Department of Psychology, University of Turku, Turku, Finland
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18
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Micioni Di Bonaventura E, Botticelli L, Del Bello F, Giorgioni G, Piergentili A, Quaglia W, Cifani C, Micioni Di Bonaventura MV. Assessing the role of ghrelin and the enzyme ghrelin O-acyltransferase (GOAT) system in food reward, food motivation, and binge eating behavior. Pharmacol Res 2021; 172:105847. [PMID: 34438062 DOI: 10.1016/j.phrs.2021.105847] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 02/06/2023]
Abstract
The peripheral peptide hormone ghrelin is a powerful stimulator of food intake, which leads to body weight gain and adiposity in both rodents and humans. The hormone, thus, increases the vulnerability to obesity and binge eating behavior. Several studies have revealed that ghrelin's functions are due to its interaction with the growth hormone secretagogue receptor type 1a (GHSR1a) in the hypothalamic area; besides, ghrelin also promotes the reinforcing properties of hedonic food, acting at extra-hypothalamic sites and interacting with dopaminergic, cannabinoid, opioid, and orexin signaling. The hormone is primarily present in two forms in the plasma and the enzyme ghrelin O-acyltransferase (GOAT) allows the acylation reaction which causes the transformation of des-acyl-ghrelin (DAG) to the active form acyl-ghrelin (AG). DAG has been demonstrated to show antagonist properties; it is metabolically active, and counteracts the effects of AG on glucose metabolism and lipolysis, and reduces food consumption, body weight, and hedonic feeding response. Both peptides seem to influence the hypothalamic-pituitary-adrenal (HPA) axis and the corticosterone/cortisol level that drive the urge to eat under stressful conditions. These findings suggest that DAG and inhibition of GOAT may be targets for obesity and bingeing-related eating disorders and that AG/DAG ratio may be an important potential biomarker to assess the risk of developing maladaptive eating behaviors.
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Affiliation(s)
| | - Luca Botticelli
- School of Pharmacy, Pharmacology Unit, University of Camerino, via Madonna delle Carceri, 9, 62032 Camerino, Italy
| | - Fabio Del Bello
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, via S. Agostino, 1, 62032 Camerino, Italy
| | - Gianfabio Giorgioni
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, via S. Agostino, 1, 62032 Camerino, Italy
| | - Alessandro Piergentili
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, via S. Agostino, 1, 62032 Camerino, Italy
| | - Wilma Quaglia
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, via S. Agostino, 1, 62032 Camerino, Italy
| | - Carlo Cifani
- School of Pharmacy, Pharmacology Unit, University of Camerino, via Madonna delle Carceri, 9, 62032 Camerino, Italy.
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19
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Bini J, Norcross M, Cheung M, Duffy A. The Role of Positron Emission Tomography in Bariatric Surgery Research: a Review. Obes Surg 2021; 31:4592-4606. [PMID: 34304378 DOI: 10.1007/s11695-021-05576-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/24/2021] [Accepted: 06/30/2021] [Indexed: 12/15/2022]
Abstract
Bariatric surgery, initially understood as restricting or bypassing the amount of food that reaches the stomach to reduce food intake and/or increase malabsorption of food to promote weight loss, is now recognized to also affect incretin signaling in the gut and promote improvements in system-wide metabolism. Positron emission tomography (PET) is an imaging technique whereby patients are injected with picomolar concentrations of radioactive molecules, below the threshold of having physiological effects, to measure spatial distributions of blood flow, metabolism, receptor, and enzyme pharmacology. Recent advances in both whole-body PET imaging and radioligand development will allow for novel research that may help clarify the roles of peripheral and central receptor/enzyme systems in treating obesity with bariatric surgery.
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Affiliation(s)
- Jason Bini
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, 801 Howard Avenue, PO Box 208048, New Haven, CT, USA.
| | | | - Maija Cheung
- Department of Surgery, Yale University School of Medicine, New Haven, CT, USA
| | - Andrew Duffy
- Department of Surgery, Yale University School of Medicine, New Haven, CT, USA
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20
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Blanco-Gandía MDC, Ródenas-González F, Pascual M, Reguilón MD, Guerri C, Miñarro J, Rodríguez-Arias M. Ketogenic Diet Decreases Alcohol Intake in Adult Male Mice. Nutrients 2021; 13:nu13072167. [PMID: 34202492 PMCID: PMC8308435 DOI: 10.3390/nu13072167] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 06/19/2021] [Accepted: 06/22/2021] [Indexed: 01/26/2023] Open
Abstract
The classic ketogenic diet is a diet high in fat, low in carbohydrates, and well-adjusted proteins. The reduction in glucose levels induces changes in the body’s metabolism, since the main energy source happens to be ketone bodies. Recent studies have suggested that nutritional interventions may modulate drug addiction. The present work aimed to study the potential effects of a classic ketogenic diet in modulating alcohol consumption and its rewarding effects. Two groups of adult male mice were employed in this study, one exposed to a standard diet (SD, n = 15) and the other to a ketogenic diet (KD, n = 16). When a ketotic state was stable for 7 days, animals were exposed to the oral self-administration paradigm to evaluate the reinforcing and motivating effects of ethanol. Rt-PCR analyses were performed evaluating dopamine, adenosine, CB1, and Oprm gene expression. Our results showed that animals in a ketotic state displayed an overall decrease in ethanol consumption without changes in their motivation to drink. Gene expression analyses point to several alterations in the dopamine, adenosine, and cannabinoid systems. Our results suggest that nutritional interventions may be a useful complementary tool in treating alcohol-use disorders.
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Affiliation(s)
| | - Francisco Ródenas-González
- Unit of Research Psychobiology of Drug Dependence, Department of Psychobiology, Facultad de Psicología, Universitat de Valencia, Avda. Blasco Ibáñez, 21, 46010 Valencia, Spain; (F.R.-G.); (M.P.); (M.D.R.); (J.M.)
| | - María Pascual
- Unit of Research Psychobiology of Drug Dependence, Department of Psychobiology, Facultad de Psicología, Universitat de Valencia, Avda. Blasco Ibáñez, 21, 46010 Valencia, Spain; (F.R.-G.); (M.P.); (M.D.R.); (J.M.)
- Department of Molecular and Cellular Pathology of Alcohol, Principe Felipe Research Center, C/Eduardo Primo Yúfera 3, 46012 Valencia, Spain;
- Department of Physiology, School of Medicine, Universitat de Valencia, Avda. Blasco Ibáñez, 15, 46010 Valencia, Spain
| | - Marina Daiana Reguilón
- Unit of Research Psychobiology of Drug Dependence, Department of Psychobiology, Facultad de Psicología, Universitat de Valencia, Avda. Blasco Ibáñez, 21, 46010 Valencia, Spain; (F.R.-G.); (M.P.); (M.D.R.); (J.M.)
| | - Consuelo Guerri
- Department of Molecular and Cellular Pathology of Alcohol, Principe Felipe Research Center, C/Eduardo Primo Yúfera 3, 46012 Valencia, Spain;
| | - José Miñarro
- Unit of Research Psychobiology of Drug Dependence, Department of Psychobiology, Facultad de Psicología, Universitat de Valencia, Avda. Blasco Ibáñez, 21, 46010 Valencia, Spain; (F.R.-G.); (M.P.); (M.D.R.); (J.M.)
| | - Marta Rodríguez-Arias
- Unit of Research Psychobiology of Drug Dependence, Department of Psychobiology, Facultad de Psicología, Universitat de Valencia, Avda. Blasco Ibáñez, 21, 46010 Valencia, Spain; (F.R.-G.); (M.P.); (M.D.R.); (J.M.)
- Correspondence: ; Tel.: +34-963864637
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21
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Head MA, Levine AS, Christian DG, Klockars A, Olszewski PK. Effect of combination of peripheral oxytocin and naltrexone at subthreshold doses on food intake, body weight and feeding-related brain gene expression in male rats. Physiol Behav 2021; 238:113464. [PMID: 34022256 DOI: 10.1016/j.physbeh.2021.113464] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 05/17/2021] [Accepted: 05/18/2021] [Indexed: 01/17/2023]
Abstract
In a recent case report involving a male with hypothalamic obesity, concurrent administration of oxytocin (OT) and an opioid receptor antagonist, naltrexone (NTX), synergistically affected energy balance. Here, by using laboratory rats, we examined whether the reported synergy between OT and NTX in the context of food intake extends beyond that one unique case. We found that intravenous OT+NTX combination, at doses subthreshold for each of the drugs individually, decreased episodic consumption of a 10% sucrose solution in non-deprived animals. Daily administration of OT and NTX just before a scheduled, 2-hour, high-fat high-sugar (HFHS) meal over 24 days, decreased cumulative HFHS diet intake, but without a change in body weight due to compensatory standard chow intake during the remainder of the day. The NTX-OT treatment affected expression of several feeding-related genes in the hypothalamus, brain stem and nucleus accumbens, brain regions essential for the regulation of energy- and reward-driven consumption. We conclude that OT and NTX act synergistically to decrease food consumption in rats and that this transient effect is accompanied by changes in brain processes relevant to feeding.
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Affiliation(s)
- Mitchell A Head
- School of Science, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | - Allen S Levine
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN, 55113 United States.
| | - David G Christian
- School of Science, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | - Anica Klockars
- School of Science, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | - Pawel K Olszewski
- School of Science, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand; Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN, 55113 United States; Department of Integrative Biology and Physiology, Medical School, University of Minnesota, Minneapolis, MN, United States
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Dvořáček J, Kodrík D. Drosophila reward system - A summary of current knowledge. Neurosci Biobehav Rev 2021; 123:301-319. [PMID: 33421541 DOI: 10.1016/j.neubiorev.2020.12.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 12/16/2020] [Accepted: 12/27/2020] [Indexed: 01/19/2023]
Abstract
The fruit fly Drosophila melanogaster brain is the most extensively investigated model of a reward system in insects. Drosophila can discriminate between rewarding and punishing environmental stimuli and consequently undergo associative learning. Functional models, especially those modelling mushroom bodies, are constantly being developed using newly discovered information, adding to the complexity of creating a simple model of the reward system. This review aims to clarify whether its reward system also includes a hedonic component. Neurochemical systems that mediate the 'wanting' component of reward in the Drosophila brain are well documented, however, the systems that mediate the pleasure component of reward in mammals, including those involving the endogenous opioid and endocannabinoid systems, are unlikely to be present in insects. The mushroom body components exhibit differential developmental age and different functional processes. We propose a hypothetical hierarchy of the levels of reinforcement processing in response to particular stimuli, and the parallel processes that take place concurrently. The possible presence of activity-silencing and meta-satiety inducing levels in Drosophila should be further investigated.
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Affiliation(s)
- Jiří Dvořáček
- Institute of Entomology, Biology Centre, CAS, and Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic.
| | - Dalibor Kodrík
- Institute of Entomology, Biology Centre, CAS, and Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
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23
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Zamyad M, Abbasnejad M, Esmaeili-Mahani S, Sheibani V, Raoof M. Pain influences food preference and food-related memory by activating the basolateral amygdala in rats. Exp Brain Res 2021; 239:79-93. [PMID: 33104830 DOI: 10.1007/s00221-020-05961-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 10/14/2020] [Indexed: 11/24/2022]
Abstract
The amygdala has been demonstrated to contribute to pain-related behavior and food preference. Here, the effect of pain on food preference and food-matched visual-cue memory, in the presence or absence of a basolateral amygdala (BLA) lesion, has been evaluated using a novel innovative apparatus and protocol. Forty adult male Wistar rats were randomly divided into five groups (n = 8) as follows: control, pain, ibuprofen + pain, BLA lesion, BLA lesion + pain groups. Bilateral lesions of the BLA were produced by passing a current of 1.5 mA for 7 s. Pain was induced on the right hind paw of the rats by sub-plantar injection of 50 μl of 2.5% formalin. The animals were encountered with four different meals including wholemeal, wholemeal + sugar, white flour, and biscuit. Each test session consisted of six trials with inter-trial intervals of 15 min. The number of visits to each meal zone and port, the amount of time spent in each food zone and port, traveled distance in each food zone, food consumption per each visit and the total food consumption were recorded. The control group showed a high biscuit preference and low white flour preference. Rats suffering BLA lesion and rats in the BLA lesion + pain group exhibited a shifted preference curve. They had a bias toward eating wholemeal + sugar rather than white flour and biscuit. This group also showed an impaired spatial memory. In conclusion, our findings suggest that the BLA may be involved in pain-induced food preference and food-matched visual-cue memory.
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Affiliation(s)
- Mahnaz Zamyad
- Department of Biology, Faculty of Sciences, Shahid Bahonar University of Kerman, P.O. Box: 76135-133, Kerman, Iran
| | - Mehdi Abbasnejad
- Department of Biology, Faculty of Sciences, Shahid Bahonar University of Kerman, P.O. Box: 76135-133, Kerman, Iran.
| | - Saeed Esmaeili-Mahani
- Department of Biology, Faculty of Sciences, Shahid Bahonar University of Kerman, P.O. Box: 76135-133, Kerman, Iran
- Laboratory of Molecular Neuroscience, Kerman Neuroscience Research Center (KNRC), Kerman University of Medical Sciences, Kerman, Iran
| | - Vahid Sheibani
- Laboratory of Molecular Neuroscience, Kerman Neuroscience Research Center (KNRC), Kerman University of Medical Sciences, Kerman, Iran
| | - Maryam Raoof
- Endodontology Research Center, Kerman University of Medical Sciences, Kerman, Iran
- Department of Orofacial Pain and Dysfunction, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
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Killeen TK, Wolf B, Greer TL, Carmody T, Rethorst CD, Trivedi MH. Gender and racial/ethnic differences in physiologic responses in the Stimulant Reduction Intervention using Dosed Exercise Study. Addict Behav 2020; 110:106546. [PMID: 32688225 PMCID: PMC7416606 DOI: 10.1016/j.addbeh.2020.106546] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 05/31/2020] [Accepted: 07/05/2020] [Indexed: 10/23/2022]
Abstract
Exercise may be beneficial for individuals in substance use disorder (SUD) treatment given the higher rates of both medical and psychiatric comorbidity, namely mood and anxiety disorders, compared to the general population. Gender and/or racial/ethnic differences in health benefits and response to prescribed exercise have been reported and may have implications for designing exercise interventions in SUD programs. METHOD Data are from the National Drug Abuse Treatment Clinical Trials Network (NIDA/CTN) Stimulant Reduction Intervention using Dosed Exercise (STRIDE) trial. Gender differences across racial/ethnic groups in physiological responses and stimulant withdrawal severity across time were analyzed using linear mixed effects models. RESULTS Males completed significantly more exercise sessions than females and were more adherent to the prescribed exercise dose of 12 Kcal/Kg/Week. Controlling for age, race/ethnicity, treatment group and stimulant withdrawal severity, there was a significant gender by time interaction for body mass index (BMI) (p < 0.001), waist circumference (p < 0.001) and heart rate measured prior to exercise sessions (p < 0.01). For females, body mass index (BMI) and waist circumference increased over time while for males BMI and waist circumference stayed unchanged or slightly decreased with time. Heart rate over time significantly increased for females at a higher rate than in males. Stimulant withdrawal severity was similar in males and females at baseline but males exhibited a significant decrease over time while females did not. Although baseline differences were observed, there were no time by race/ethnicity differences in physiologic responses. DISCUSSION Gender differences in response to exercise may have implications for developing gender specific exercise interventions in SUD programs.
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Affiliation(s)
- T K Killeen
- Medical University of South Carolina, Charleston, SC, USA.
| | - B Wolf
- Medical University of South Carolina, Charleston, SC, USA
| | - T L Greer
- University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - T Carmody
- University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - C D Rethorst
- University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - M H Trivedi
- University of Texas Southwestern Medical Center, Dallas, TX, USA
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Narmaki E, Borazjani M, Ataie-Jafari A, Hariri N, Doost AH, Qorbani M, Saidpour A. The combined effects of probiotics and restricted calorie diet on the anthropometric indices, eating behavior, and hormone levels of obese women with food addiction : a randomized clinical trial. Nutr Neurosci 2020; 25:963-975. [PMID: 33054635 DOI: 10.1080/1028415x.2020.1826763] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND AND AIM Food addiction (FA) is an important contributor to obesity. Alterations in gut microbiota (GM) diversity and composition have also been proposed to play a pivotal role in obesity pathogenesis. This trial aimed to assess the effects of probiotic supplementation on the anthropometric indices, eating behavior, and hormone levels of obese women with FA. METHODS This randomized, double-blind, placebo-controlled clinical trial was conducted among obese women with FA. Participants (n = 62) received a restricted calorie diet (RCD) plus either probiotic, or placebo for 12 weeks. Anthropometric measurements, biochemical markers, eating behavior and appetite were assessed during the study period. RESULTS Probiotics administration significantly reduced weight, body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR), body fat percentage (BFP), and trunk fat percentage (TFP) compared to the placebo group (p < 0.001). Also, a significant improvement was observed in eating behavior in the probiotic group compared to the placebo group (p < 0.001).Serum levels of oxytocin increased and NPY decreased significantly in the probiotic group compared to the placebo group (p = 0.02, p = 0.002, respectively). Moreover, leptin level significantly decreased in the probiotic group compared to the baseline values (p < 0.001), while probiotics did not cause a greater significant reduction in leptin level, compared to the placebo group. CONCLUSION Multi-probiotic supplementation may have beneficial effects on anthropometric indices, eating behavior, and some appetite-regulating hormones in obese women with FA.Trial registration: Iranian Registry of Clinical Trials identifier: IRCT20131228015968N5.
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Affiliation(s)
- Elham Narmaki
- National Nutrition and Food Technology Research Institute, Department of Clinical Nutrition & Dietetics, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohaddeseh Borazjani
- School of Nutrition and Food Science, Shiraz University of Medical Science, Iran
| | - Asal Ataie-Jafari
- Department of Nutrition, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Nastaran Hariri
- National Nutrition and Food Technology Research Institute, Department of Clinical Nutrition & Dietetics, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Azita Hekmat Doost
- National Nutrition and Food Technology Research Institute, Department of Clinical Nutrition & Dietetics, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mostafa Qorbani
- Non-communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran
| | - Atoosa Saidpour
- National Nutrition and Food Technology Research Institute, Department of Clinical Nutrition & Dietetics, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Bi GH, Galaj E, He Y, Xi ZX. Cannabidiol inhibits sucrose self-administration by CB1 and CB2 receptor mechanisms in rodents. Addict Biol 2020; 25:e12783. [PMID: 31215752 PMCID: PMC6920611 DOI: 10.1111/adb.12783] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 04/03/2019] [Accepted: 05/03/2019] [Indexed: 12/14/2022]
Abstract
A growing number of studies suggest therapeutic applications of cannabidiol (CBD), a recently U.S. Food and Drug Administration (FDA)-approved medication for epilepsy, in treatment of many other neuropsychological disorders. However, pharmacological action and the mechanisms by which CBD exerts its effects are not fully understood. Here, we examined the effects of CBD on oral sucrose self-administration in rodents and explored the receptor mechanisms underlying CBD-induced behavioral effects using pharmacological and transgenic approaches. Systemic administration of CBD (10, 20, and 40 mg/kg, ip) produced a dose-dependent reduction in sucrose self-administration in rats and in wild-type (WT) and CB1-/- mice but not in CB2-/- mice. CBD appeared to be more efficacious in CB1-/- mice than in WT mice. Similarly, pretreatment with AM251, a CB1R antagonist, potentiated, while AM630, a selective CB2R antagonist, blocked CBD-induced reduction in sucrose self-administration, suggesting the involvement of CB1 and CB2 receptors. Furthermore, systemic administration of JWH133, a selective CB2R agonist, also produced a dose-dependent reduction in sucrose self-administration in WT and CB1-/- mice, but not in CB2-/- mice. Pretreatment with AM251 enhanced, while AM630 blocked JWH133-induced reduction in sucrose self-administration in WT mice, suggesting that CBD inhibits sucrose self-administration likely by CB1 receptor antagonism and CB2 receptor agonism. Taken together, the present findings suggest that CBD may have therapeutic potential in reducing binge eating and the development of obesity.
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MESH Headings
- Animals
- Behavior, Animal/drug effects
- Cannabidiol/pharmacology
- Cannabinoid Receptor Agonists/pharmacology
- Cannabinoid Receptor Antagonists/pharmacology
- Cannabinoids/pharmacology
- Feeding Behavior/drug effects
- Indoles/pharmacology
- Mice
- Mice, Knockout
- Piperidines/pharmacology
- Pyrazoles/pharmacology
- Rats
- Receptor, Cannabinoid, CB1/antagonists & inhibitors
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/antagonists & inhibitors
- Receptor, Cannabinoid, CB2/genetics
- Receptor, Cannabinoid, CB2/metabolism
- Self Administration
- Sucrose/administration & dosage
- Sweetening Agents/administration & dosage
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Affiliation(s)
- Guo-Hua Bi
- Addiction Biology Unit, Molecular Targets and Medication Discoveries Branch, Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
| | - Ewa Galaj
- Addiction Biology Unit, Molecular Targets and Medication Discoveries Branch, Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
| | - Yi He
- Addiction Biology Unit, Molecular Targets and Medication Discoveries Branch, Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
| | - Zheng-Xiong Xi
- Addiction Biology Unit, Molecular Targets and Medication Discoveries Branch, Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
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Neuroimaging of Sex/Gender Differences in Obesity: A Review of Structure, Function, and Neurotransmission. Nutrients 2020; 12:nu12071942. [PMID: 32629783 PMCID: PMC7400469 DOI: 10.3390/nu12071942] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 06/24/2020] [Accepted: 06/25/2020] [Indexed: 02/06/2023] Open
Abstract
While the global prevalence of obesity has risen among both men and women over the past 40 years, obesity has consistently been more prevalent among women relative to men. Neuroimaging studies have highlighted several potential mechanisms underlying an individual’s propensity to become obese, including sex/gender differences. Obesity has been associated with structural, functional, and chemical alterations throughout the brain. Whereas changes in somatosensory regions appear to be associated with obesity in men, reward regions appear to have greater involvement in obesity among women than men. Sex/gender differences have also been observed in the neural response to taste among people with obesity. A more thorough understanding of these neural and behavioral differences will allow for more tailored interventions, including diet suggestions, for the prevention and treatment of obesity.
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28
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Lin E, Schmid PC. The Experience of Power Could Facilitate Healthy Food Consumption. SOCIAL COGNITION 2020. [DOI: 10.1521/soco.2020.38.3.197] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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29
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Food texture affects glucose tolerance by altering pancreatic β-cell function in mice consuming high-fructose corn syrup. PLoS One 2020; 15:e0233797. [PMID: 32470042 PMCID: PMC7259500 DOI: 10.1371/journal.pone.0233797] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 05/12/2020] [Indexed: 12/12/2022] Open
Abstract
The incidence of metabolic diseases, such as type 2 diabetes, has increased steadily worldwide. Diet, beverages, and food texture can all markedly influence these metabolic disorders. However, the combined effects of food texture and beverages on energy metabolism remains unclear. In the present study, we examined the effect of food texture on energy metabolism in mice administered high-fructose corn syrup (HFCS). Mice were fed a soft or hard diet along with 4.2% HFCS or tap water. Body weight and total caloric intake were not affected by food texture irrespective of HFCS consumption. However, caloric intake from HFCS (i.e., drinking volume) and diet were higher and lower, respectively, in the hard food group than in the soft food group. The hard food group’s preference for HFCS was absent in case of mice treated with the μ-opioid receptor antagonist naltrexone. Despite increased HFCS consumption, blood glucose levels were lower in the hard-diet group than in the soft-diet group. In HFCS-fed mice, insulin levels after glucose stimulation and insulin content in the pancreas were higher in the hard food group than the soft food group, whereas insulin tolerance did not differ between the groups. These food texture-induced differences in glucose tolerance were not observed in mice fed tap water. Thus, food texture appears to affect glucose tolerance by influencing pancreatic β-cell function in HFCS-fed mice. These data shed light on the combined effects of eating habits and food texture on human health.
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Calderwood MT, Tseng A, Glenn Stanley B. Lateral septum mu opioid receptors in stimulation of feeding. Brain Res 2020; 1734:146648. [PMID: 31926909 DOI: 10.1016/j.brainres.2020.146648] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 01/03/2020] [Accepted: 01/04/2020] [Indexed: 12/13/2022]
Abstract
Stimulation of mu opioid receptors using drugs like morphine can increase eating when injected into multiple brain regions including the lateral septum (LS). The LS has been classically associated with reward, anxiety and fearful behaviors but more recently has also received attention with regard to control of feeding. To investigate the role of LS opioid receptors in feeding, we injected mu, delta, and kappa opioid receptor agonists and a mu specific receptor antagonist directly into the LS of rats. We expected that if feeding is mu receptor specific then only mu receptor agonists would increase feeding. We also hypothesized that mu receptor antagonists would suppress the feeding elicited by mu receptor agonists like morphine. Further, because the LS is densely populated with GABA receptors, we used the GABAA receptor agonist muscimol to assess the effect of inhibition of LS neurons on feeding. Our results show that the mu receptor agonist morphine and the specific mu agonist DAMGO reliably and significantly increase feeding behavior across doses tested, while delta and kappa agonists were ineffective. CTAP, a specific mu receptor antagonist, at low doses unexpectedly increased morphine-elicited feeding but at high doses decreased morphine's effect, consistent with mediation by mu receptors. Finally, muscimol rapidly elicited feeding, suggesting a role for LS GABAA receptors in feeding stimulation. These findings suggest that mu opioid receptors in the LS play complex roles in feeding and that neural inhibition may be a mechanism by which they elicit feeding.
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Affiliation(s)
- Michelle T Calderwood
- Department of Psychology, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, United States.
| | - Andy Tseng
- Neuroscience Graduate Program, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, United States
| | - B Glenn Stanley
- Department of Psychology, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, United States; Neuroscience Graduate Program, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, United States; Department of Molecular, Cell, System Biology, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, United States
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31
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Simon MJ, Zafra MA, Puerto A. Differential rewarding effects of electrical stimulation of the lateral hypothalamus and parabrachial complex: Functional characterization and the relevance of opioid systems and dopamine. J Psychopharmacol 2019; 33:1475-1490. [PMID: 31282233 DOI: 10.1177/0269881119855982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Since the discovery of rewarding intracranial self-stimulation by Olds and Milner, extensive data have been published on the biological basis of reward. Although participation of the mesolimbic dopaminergic system is well documented, its precise role has not been fully elucidated, and some authors have proposed the involvement of other neural systems in processing specific aspects of reinforced behaviour. AIMS AND METHODS We reviewed published data, including our own findings, on the rewarding effects induced by electrical stimulation of the lateral hypothalamus (LH) and of the external lateral parabrachial area (LPBe) - a brainstem region involved in processing the rewarding properties of natural and artificial substances - and compared its functional characteristics as observed in operant and non-operant behavioural procedures. RESULTS Brain circuits involved in the induction of preferences for stimuli associated with electrical stimulation of the LBPe appear to functionally and neurochemically differ from those activated by electrical stimulation of the LH. INTERPRETATION We discuss the possible involvement of the LPBe in processing emotional-affective aspects of the brain reward system.
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Affiliation(s)
- Maria J Simon
- Department of Psychobiology, Mind, Brain and Behaviour Research Center (CIMCYC), University of Granada, Granada, Spain
| | - Maria A Zafra
- Department of Psychobiology, Mind, Brain and Behaviour Research Center (CIMCYC), University of Granada, Granada, Spain
| | - Amadeo Puerto
- Department of Psychobiology, Mind, Brain and Behaviour Research Center (CIMCYC), University of Granada, Granada, Spain
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Yen E, Kaneko-Tarui T, Ruthazer R, Harvey-Wilkes K, Hassaneen M, Maron JL. Sex-Dependent Gene Expression in Infants with Neonatal Opioid Withdrawal Syndrome. J Pediatr 2019; 214:60-65.e2. [PMID: 31474426 PMCID: PMC10564583 DOI: 10.1016/j.jpeds.2019.07.032] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 06/14/2019] [Accepted: 07/11/2019] [Indexed: 12/11/2022]
Abstract
OBJECTIVES To evaluate salivary biomarkers that elucidate the molecular mechanisms by which in utero opioid exposure exerts sex-specific effects on select hypothalamic and reward genes driving hyperphagia, a hallmark symptom of infants suffering from neonatal opioid withdrawal syndrome (NOWS). STUDY DESIGN We prospectively collected saliva from 50 newborns born at ≥34 weeks of gestational age with prenatal opioid exposure and 50 sex- and gestational age-matched infants without exposure. Saliva underwent transcriptomic analysis for 4 select genes involved in homeostatic and hedonic feeding regulation (neuropeptide Y2 receptor [NPY2R], proopiomelanocortin [POMC], leptin receptor [LEPR], dopamine type 2 receptor [DRD2]). Normalized gene expression data were stratified based on sex and correlated with feeding volume on day of life 7 and length of stay in infants with NOWS requiring pharmacotherapy. RESULTS Expression of DRD2, a hedonistic/reward regulator, was significantly higher in male newborns compared with female newborns with NOWS (Δ threshold cycle 10.8 ± 3.8 vs 13.9 ± 3.7, P = .01). In NOWS requiring pharmacotherapy expression of leptin receptor, an appetite suppressor, was higher in male subjects than female subjects (Δ threshold cycle 8.4 ± 2.5 vs 12.4 ± 5.1, P = .05), DRD2 expression significantly correlated with intake volume on day of life 7 (r = 0.58, P = .02), and expression of NPY2R, an appetite regulator, negatively correlated with length of stay (r = -0.24, P = .05). CONCLUSIONS Prenatal opioid exposure exerts sex-dependent effects on hypothalamic feeding regulatory genes with clinical correlations. Neonatal salivary gene expression analyses may predict hyperphagia, severity of withdrawal state, and length of stay in infants with NOWS.
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Affiliation(s)
- Elizabeth Yen
- Department of Pediatrics, Floating Hospital for Children/Tufts University School of Medicine, Boston, MA.
| | | | - Robin Ruthazer
- Biostatistics, Epidemiology, and Research Design, Tufts Medical Center, Boston, MA
| | - Karen Harvey-Wilkes
- Department of Pediatrics, Floating Hospital for Children/Tufts University School of Medicine, Boston, MA
| | | | - Jill L Maron
- Department of Pediatrics, Floating Hospital for Children/Tufts University School of Medicine, Boston, MA; Mother Infant Research Institute, Tufts Medical Center, Boston, MA
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Farr OM, Pilitsi E, Mantzoros CS. Of mice and men: incretin actions in the central nervous system. Metabolism 2019; 98:121-135. [PMID: 31173757 DOI: 10.1016/j.metabol.2019.05.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 05/30/2019] [Accepted: 05/31/2019] [Indexed: 02/06/2023]
Abstract
Incretins have risen to the forefront of therapies for obesity and related metabolic complications, primarily because of their efficacy and relatively few side effects. Importantly, their efficacy in altering energy balance and decreasing body weight is apparently through actions in the central nervous system (CNS); the latter may have implications beyond obesity per se, i.e. in other disease states associated with obesity including CNS-related disorders. Here, we first describe the role of the CNS in energy homeostasis and then the current state of knowledge in terms of incretin physiology, pathophysiology and efficacy in preclinical and clinical studies. In the future, more clinical studies are needed to fully map mechanistic pathways underlying incretin actions and outcomes in the human CNS. Additionally, future research will likely lead to the discovery of additional novel incretins and/or more efficacious medications with less side effects through the improvement of current compounds with properties that would allow them to have more favorable pharmacokinetic and pharmacodynamic profiles and/or by combining known and novel incretins into safe and more efficacious combination therapies leading ultimately to more tangible benefits for our patients.
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Affiliation(s)
- Olivia M Farr
- Division of Endocrinology, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA 02215, United States of America.
| | - Eleni Pilitsi
- Division of Endocrinology, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA 02215, United States of America
| | - Christos S Mantzoros
- Division of Endocrinology, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA 02215, United States of America; Section of Endocrinology, VA Boston Healthcare System, Boston, MA 02130, United States of America
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34
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Lee JR, Tapia MA, Weise VN, Bathe EL, Vieira-Potter VJ, Booth FW, Will MJ. Voluntary wheel running effects on intra-accumbens opioid driven diet preferences in male and female rats. Neuropharmacology 2019; 155:22-30. [PMID: 31100290 DOI: 10.1016/j.neuropharm.2019.05.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 05/08/2019] [Accepted: 05/13/2019] [Indexed: 10/26/2022]
Abstract
Palatability driven feeding and voluntary physical activity are mediated by and influence similar neural mechanisms, notably through the actions of opioids within the nucleus accumbens. Recent studies suggest that access to a voluntary running wheel results in sex dependent behavioral and physiological adaptations related to opioid mediated palatability-driven feeding. To explore this relationship, male and female Wistar rats were given either access to a voluntary running wheel (RUN group) or no access (SED group) for one week prior to being stereotaxically implanted with bilateral cannulae targeting the nucleus accumbens. Following 7 days of recovery, with RUN or SED conditions continuing the duration of the experiment, all rats were assessed daily (2 h/day) for feeding behavior of concurrently accessible high-carbohydrate and high-fat diet for one week. Following this week, all rats were administered the μ-opioid receptor agonist D-Ala2, NMe-Phe4, Glyol5-enkephalin (DAMGO) (0.0025 μg, 0.025 μg, or 0.25 μg/0.5 μl/side) or the opioid antagonist naloxone (20 μg/0.5 μl/side) into the nucleus accumbens and given concurrent access (2 h) to both diets. All groups expressed a significant baseline preference for the high-carbohydrate diet. DAMGO administration, compared to saline treatment, led to significant increased consumption of the high-carbohydrate diet in all treatment groups. While high-fat diet consumption also increased following DAMGO administration, the influence of DAMGO was much more robust for the preferred high-carbohydrate diet in all groups. Compared to males, females consumed significantly more of both diets at baseline and following DAMGO treatment. Both male and female rats in the RUN condition consumed more high-carbohydrate diet compared to rats in the SED condition. While males exhibited similar increased consumption of both diets regardless of RUN or SED condition, females in the RUN condition displayed a greater sensitivity to DAMGO-driven consumption of the preferred high-carbohydrate, compared to SED females.
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Affiliation(s)
- Jenna R Lee
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA
| | - Melissa A Tapia
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Valerie N Weise
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Emily L Bathe
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | | | - Frank W Booth
- Department of Biomedical Sciences, University of Missouri, Columbia, MO, USA
| | - Matthew J Will
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, USA; Department of Psychological Sciences, University of Missouri, Columbia, MO, USA.
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35
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Aslam H, Ruusunen A, Berk M, Loughman A, Rivera L, Pasco JA, Jacka FN. Unravelled facets of milk derived opioid peptides: a focus on gut physiology, fractures and obesity. Int J Food Sci Nutr 2019; 71:36-49. [PMID: 31154909 DOI: 10.1080/09637486.2019.1614540] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Beyond being a source of key nutrients, bovine milk influences physiological functions by synthesising bioactive peptides during the process of digestion. Some of the claimed negative health outcomes associated with milk consumption, such as cardiovascular diseases and type 1 diabetes may be attributed to an opioid peptide, beta-casomorphin-7 (BCM-7), derived from A1 beta-casein. BCM-7 exerts its function by binding to the μ-opioid receptors in the body. It is hypothesised that activation of the μ-opioid receptors in the gut can alter gut microbial composition, impair gut barrier integrity and bile acid metabolism, in addition to increasing gastrointestinal transit time and gut inflammation. Further, it is hypothesised that BCM-7 may influence fractures and obesity via μ-opioid receptor pathways. In conclusion, it appears that BCM-7 might have multiple functions pertinent to human health; however, the evidence is limited and warrants further pre-clinical and clinical studies for hypothesis confirmation.
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Affiliation(s)
- Hajara Aslam
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia
| | - Anu Ruusunen
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.,Department of Psychiatry, Kuopio University Hospital, Kuopio, Finland.,Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - Michael Berk
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.,Department of Psychiatry, Orygen Youth Health Research Centre and the Centre of Youth Mental Health, The Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne, Australia.,Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia.,Barwon Health, Geelong, Australia
| | - Amy Loughman
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia
| | - Leni Rivera
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.,Metabolic Research Unit, School of Medicine, Waurn Ponds, Deakin University Victoria, Geelong, Australia
| | - Julie A Pasco
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.,Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia.,Barwon Health, Geelong, Australia.,Department of Medicine-Western Health, Melbourne Medical School, The University of Melbourne, St Albans, Australia
| | - Felice N Jacka
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.,Department of Psychiatry, University of Melbourne, Melbourne, Australia.,Centre for Adolescent Health, Murdoch Children's Research Institute, Melbourne, Australia.,Black Dog Institute, New South Wales, Australia
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Bodnar RJ. Endogenous opioid modulation of food intake and body weight: Implications for opioid influences upon motivation and addiction. Peptides 2019; 116:42-62. [PMID: 31047940 DOI: 10.1016/j.peptides.2019.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 03/04/2019] [Accepted: 04/08/2019] [Indexed: 12/12/2022]
Abstract
This review is part of a special issue dedicated to Opioid addiction, and examines the influential role of opioid peptides, opioid receptors and opiate drugs in mediating food intake and body weight control in rodents. This review postulates that opioid mediation of food intake was an example of "positive addictive" properties that provide motivational drives to maintain opioid-seeking behavior and that are not subject to the "negative addictive" properties associated with tolerance, dependence and withdrawal. Data demonstrate that opiate and opioid peptide agonists stimulate food intake through homeostatic activation of sensory, metabolic and energy-related In contrast, general, and particularly mu-selective, opioid receptor antagonists typically block these homeostatically-driven ingestive behaviors. Intake of palatable and hedonic food stimuli is inhibited by general, and particularly mu-selective, opioid receptor antagonists. The selectivity of specific opioid agonists to elicit food intake was confirmed through the use of opioid receptor antagonists and molecular knockdown (antisense) techniques incapacitating specific exons of opioid receptor genes. Further extensive evidence demonstrated that homeostatic and hedonic ingestive situations correspondingly altered the levels and expression of opioid peptides and opioid receptors. Opioid mediation of food intake was controlled by a distributed brain network intimately related to both the appetitive-consummatory sites implicated in food intake as well as sites intimately involved in reward and reinforcement. This emergent system appears to sustain the "positive addictive" properties providing motivational drives to maintain opioid-seeking behavior.
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology, Queens College, City University of New York, United States; Psychology Doctoral Program and CUNY Neuroscience Collaborative, The Graduate Center of the City University of New York, United States.
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Identification of central mechanisms underlying anorexigenic effects of intraperitoneal L-tryptophan. Neuroreport 2019; 29:1293-1300. [PMID: 30085976 DOI: 10.1097/wnr.0000000000001110] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A free essential amino acid, L-tryptophan (TRP), administered through a diet or directly into the gut, decreases food intake by engaging neural mechanisms. The ability of intragastric TRP to cross into the general circulation and through the blood-brain barrier, at least partly underlies hypophagia. It is unclear although, whether TRP's anorexigenic effects and accompanying neural processes occur in the absence of the initial action of TRP on the gut mucosa. Here, we addressed this issue by using a fundamental approach of examining effects of intraperitoneally administered TRP on feeding and neuronal activation in rats. We found that 30 mg/kg, intraperitoneal, TRP decreases deprivation-induced intake of standard chow and thirst-driven water intake. A 100 mg/kg dose was necessary to suppress consumption of palatable chow and of sucrose and saccharin solutions in nondeprived animals. Intraperitoneally TRP did not induce a conditioned taste aversion; thus, its anorexigenic effects were unrelated to sickness/malaise. c-Fos mapping in feeding-related brain sites revealed TRP-induced changes in the dorsal vagal complex, hypothalamic paraventricular and supraoptic nuclei and in the basolateral amygdala. TRP enhanced activation of hypothalamic neurons synthesizing an anorexigen, oxytocin (OT). Pharmacological blockade of the OT receptor with a blood-brain barrier -penetrant antagonist, L-368,899, attenuated TRP-induced decrease in deprivation-induced chow intake, but not in thirst-driven water consumption. We conclude that TRP triggers anorexigenic action and underlying neural responses even when it does not directly contact the gut mucosa. TRP requires OT to decrease energy intake, whereas OT is nonobligatory in TRP's effects on drinking behavior.
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Olszewski PK, Wood EL, Klockars A, Levine AS. Excessive Consumption of Sugar: an Insatiable Drive for Reward. Curr Nutr Rep 2019; 8:120-128. [DOI: 10.1007/s13668-019-0270-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Klockars A, Wood EL, Gartner SN, McColl LK, Levine AS, Carpenter EA, Prosser CG, Olszewski PK. Palatability of Goat's versus Cow's Milk: Insights from the Analysis of Eating Behavior and Gene Expression in the Appetite-Relevant Brain Circuit in Laboratory Animal Models. Nutrients 2019; 11:nu11040720. [PMID: 30925727 PMCID: PMC6520687 DOI: 10.3390/nu11040720] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 03/17/2019] [Accepted: 03/25/2019] [Indexed: 01/20/2023] Open
Abstract
Goat's (GM) and cow's milk (CM) are dietary alternatives with select health benefits shown in human and animal studies. Surprisingly, no systematic analysis of palatability or preference for GM vs. CM has been performed to date. Here, we present a comprehensive investigation of short-term intake and palatability profiles of GM and CM in laboratory mice and rats. We studied consumption in no-choice and choice scenarios, including meal microstructure, and by using isocaloric milks and milk-enriched solid diets. Feeding results are accompanied by qPCR data of relevant genes in the energy balance-related hypothalamus and brain stem, and in the nucleus accumbens, which regulates eating for palatability. We found that GM and CM are palatable to juvenile, adult, and aged rodents. Given a choice, animals prefer GM- to CM-based diets. Analysis of meal microstructure using licking patterns points to enhanced palatability of and, possibly, greater motivation toward GM over CM. Most profound changes in gene expression after GM vs. CM were associated with the brain systems driving consumption for reward. We conclude that, while both GM and CM are palatable, GM is preferred over CM by laboratory animals, and this preference is driven by central mechanisms controlling eating for pleasure.
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Affiliation(s)
- Anica Klockars
- Faculty of Science and Engineering, University of Waikato, Hamilton 3240, New Zealand.
| | - Erin L Wood
- Faculty of Science and Engineering, University of Waikato, Hamilton 3240, New Zealand.
| | - Sarah N Gartner
- Faculty of Science and Engineering, University of Waikato, Hamilton 3240, New Zealand.
| | - Laura K McColl
- Faculty of Science and Engineering, University of Waikato, Hamilton 3240, New Zealand.
| | - Allen S Levine
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN 55113, USA.
| | | | - Colin G Prosser
- Dairy Goat Cooperative (NZ) Ltd., Hamilton 3206, New Zealand.
| | - Pawel K Olszewski
- Faculty of Science and Engineering, University of Waikato, Hamilton 3240, New Zealand.
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN 55113, USA.
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Saanijoki T, Nummenmaa L, Tuulari JJ, Tuominen L, Arponen E, Kalliokoski KK, Hirvonen J. Aerobic exercise modulates anticipatory reward processing via the μ-opioid receptor system. Hum Brain Mapp 2018; 39:3972-3983. [PMID: 29885086 DOI: 10.1002/hbm.24224] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 04/20/2018] [Accepted: 05/10/2018] [Indexed: 01/18/2023] Open
Abstract
Physical exercise modulates food reward and helps control body weight. The endogenous µ-opioid receptor (MOR) system is involved in rewarding aspects of both food and physical exercise, yet interaction between endogenous opioid release following exercise and anticipatory food reward remains unresolved. Here we tested whether exercise-induced opioid release correlates with increased anticipatory reward processing in humans. We scanned 24 healthy lean men after rest and after a 1 h session of aerobic exercise with positron emission tomography (PET) using MOR-selective radioligand [11 C]carfentanil. After both PET scans, the subjects underwent a functional magnetic resonance imaging (fMRI) experiment where they viewed pictures of palatable versus nonpalatable foods to trigger anticipatory food reward responses. Exercise-induced changes in MOR binding in key regions of reward circuit (amygdala, thalamus, ventral and dorsal striatum, and orbitofrontal and cingulate cortices) were used to predict the changes in anticipatory reward responses in fMRI. Exercise-induced changes in MOR binding correlated negatively with the exercise-induced changes in neural anticipatory food reward responses in orbitofrontal and cingulate cortices, insula, ventral striatum, amygdala, and thalamus: higher exercise-induced opioid release predicted higher brain responses to palatable versus nonpalatable foods. We conclude that MOR activation following exercise may contribute to the considerable interindividual variation in food craving and consumption after exercise, which might promote compensatory eating and compromise weight control.
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Affiliation(s)
| | - Lauri Nummenmaa
- Turku PET Centre, University of Turku, Turku, Finland.,Department of Psychology, University of Turku, Turku, Finland
| | | | - Lauri Tuominen
- Turku PET Centre, University of Turku, Turku, Finland.,Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | | | | | - Jussi Hirvonen
- Turku PET Centre, University of Turku, Turku, Finland.,Department of Radiology, Turku University Hospital, Turku, Finland
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Clough SJ, Hudson RL, Dubocovich ML. Food-induced reinforcement is abrogated by the genetic deletion of the MT 1 or MT 2 melatonin receptor in C3H/HeN mice. Behav Brain Res 2018; 343:28-35. [PMID: 29374562 PMCID: PMC5842708 DOI: 10.1016/j.bbr.2018.01.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 12/17/2017] [Accepted: 01/22/2018] [Indexed: 01/08/2023]
Abstract
Palatable food is known for its ability to enhance reinforcing responses. Studies have suggested a circadian variation in both drug and natural reinforcement, with each following its own time course. The goal of this study was to determine the role of the MT1 and MT2 melatonin receptors in palatable snack food-induced reinforcement, as measured by the conditioned place preference (CPP) paradigm during the light and dark phases. C3H/HeN wild-type mice were trained for snack food-induced CPP at either ZT 6 - 8 (ZT: Zeitgeber time; ZT 0 = lights on), when endogenous melatonin levels are low, or ZT 19 - 21, when melatonin levels are high. These time points also correspond to the high and low points for expression of the circadian gene Period1, respectively. The amount of snack food (chow, Cheetos®, Froot Loops® and Oreos®) consumed was of similar magnitude at both times, however only C3H/HeN mice conditioned to snack food at ZT 6 - 8 developed a place preference. C3H/HeN mice with a genetic deletion of either the MT1 (MT1KO) or MT2 (MT2KO) receptor tested at ZT 6 - 8 did not develop a place preference for snack food. Although the MT2KO mice showed a similar amount of snack food consumed when compared to wild-type mice, the MT1KO mice consumed significantly less than either genotype. We conclude that in our mouse model snack food-induced CPP is dependent on time of day and the presence of the MT1 or MT2 receptors, suggesting a role for melatonin and its receptors in snack food-induced reinforcement.
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MESH Headings
- Animals
- Conditioning, Psychological/physiology
- Feeding Behavior/physiology
- Feeding Behavior/psychology
- Food
- Male
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Knockout
- Photoperiod
- Receptor, Melatonin, MT1/deficiency
- Receptor, Melatonin, MT1/genetics
- Receptor, Melatonin, MT2/deficiency
- Receptor, Melatonin, MT2/genetics
- Reinforcement, Psychology
- Spatial Behavior/physiology
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Affiliation(s)
- Shannon J Clough
- Department of Pharmacology & Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14214, United States
| | - Randall L Hudson
- Department of Physiology & Biophysics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14214, United States
| | - Margarita L Dubocovich
- Department of Pharmacology & Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14214, United States.
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Kosheleff AR, Araki J, Hsueh J, Le A, Quizon K, Ostlund SB, Maidment NT, Murphy NP. Pattern of access determines influence of junk food diet on cue sensitivity and palatability. Appetite 2018; 123:135-145. [PMID: 29248689 PMCID: PMC5817006 DOI: 10.1016/j.appet.2017.12.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 11/03/2017] [Accepted: 12/07/2017] [Indexed: 12/31/2022]
Abstract
AIMS Like drug addiction, cues associated with palatable foods can trigger food-seeking, even when sated. However, whether susceptibility to the motivating influence of food-related cues is a predisposing factor in overeating or a consequence of poor diet is difficult to determine in humans. Using a rodent model, we explored whether a highly palatable 'junk food' diet impacts responses to reward-paired cues in a Pavlovian-to-instrumental transfer test, using sweetened condensed milk (SCM) as the reward. The hedonic impact of SCM consumption was also assessed by analyzing licking microstructure. METHODS To probe the effects of pattern and duration of junk food exposure, we provided rats with either regular chow ad libitum (controls) or chow plus access to junk food for either 2 or 24 h per day for 1, 3, or 6 weeks. We also examined how individual susceptibility to weight gain related to these measures. RESULTS Rats provided 24 h access to the junk food diet were insensitive to the motivational effects of a SCM-paired cue when tested sated even though their hedonic experience upon reward consumption was similar to controls. In contrast, rats provided restricted, 2 h access to junk food exhibited a cue generalization phenotype under sated conditions, lever-pressing with increased vigor in response to both a SCM-paired cue, and a cue not previously paired with reward. Hedonic response was also significantly higher in these animals relative to controls. CONCLUSIONS These data demonstrate that the pattern of junk food exposure differentially alters the hedonic impact of palatable foods and susceptibility to the motivating influence of cues in the environment to promote food-seeking actions when sated, which may be consequential for understanding overeating and obesity.
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Affiliation(s)
- Alisa R Kosheleff
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, 675 Charles E Young Dr. South, MRL #2762, Los Angeles, CA 90095, USA; Department of Psychology, University of California, Los Angeles, CA, USA.
| | - Jingwen Araki
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, 675 Charles E Young Dr. South, MRL #2762, Los Angeles, CA 90095, USA
| | - Jennifer Hsueh
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, 675 Charles E Young Dr. South, MRL #2762, Los Angeles, CA 90095, USA
| | - Andrew Le
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, 675 Charles E Young Dr. South, MRL #2762, Los Angeles, CA 90095, USA
| | - Kevin Quizon
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, 675 Charles E Young Dr. South, MRL #2762, Los Angeles, CA 90095, USA
| | - Sean B Ostlund
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, 675 Charles E Young Dr. South, MRL #2762, Los Angeles, CA 90095, USA; Department of Anesthesiology and Perioperative Care, University of California, 3111 Gillespie Neuroscience Research Facility 837 Health Sciences Rd, Irvine, CA 92697, USA
| | - Nigel T Maidment
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, 675 Charles E Young Dr. South, MRL #2762, Los Angeles, CA 90095, USA
| | - Niall P Murphy
- Hatos Center for Neuropharmacology, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, 675 Charles E Young Dr. South, MRL #2762, Los Angeles, CA 90095, USA
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43
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Strahler J, Nater UM. Differential effects of eating and drinking on wellbeing—An ecological ambulatory assessment study. Biol Psychol 2018; 131:72-88. [DOI: 10.1016/j.biopsycho.2017.01.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 12/07/2016] [Accepted: 01/18/2017] [Indexed: 10/20/2022]
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Waluga M, Jonderko K, Domosławska E, Matwiejszyn A, Dzielicki M, Krusiec-Świdergoł B, Kasicka-Jonderko A. Effects of taste stimulation on gastric myoelectrical activity and autonomic balance. Saudi J Gastroenterol 2018; 24:100-108. [PMID: 29637917 PMCID: PMC5900469 DOI: 10.4103/sjg.sjg_419_17] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND/AIM Sham feeding, reproducing the cephalic phase of digestion, and involving combined visual, olfactory, and taste stimulation affects gastrointestinal motility and secretory functions of the digestive system, as well as the sympathetic/parasympathetic balance (SPB). In this study, we aimed to check if taste stimulation with a single flavor affects the gastric myoelectrical activity (GMA) and/or SPB. MATERIALS AND METHODS Eighteen healthy volunteers underwent, on four separate days, 30-min electrogastrographic and electrocardiographic recordings: basal, with stimulation - while keeping in the mouth an agar cube with taste-delivering substance, and postexposure. Concentrations of saccharose, NaCl, citric acid, and quinine hydrochloride within the cubes were adjusted to 100-fold the individual taste recognition thresholds. SPB was determined from the heart rate variability (HRV) analysis of the recorded electrocardiograms. RESULTS A moderate but statistically significant increase in tachygastria and bradygastria percentage time share was observed, regardless of the type of taste applied. Bitter taste elicited a considerable decrease in the normogastria time share (from 82.8 ± 2.5% to 73.5 ± 3.5%, P = 0.00076) and a diminution of the dominant frequency (from 3.07 ± 0.08 to 2.90 ± 0.10 cycles per minute (cpm) postexposure, P = 0.01). Sour taste brought about a drop of the dominant power (from 42.5 ± 1.1 to 40.1 ± 1.4 dB, P = 0.0015). Two tastes hindered propagation of the gastric slow waves - the average percentage of slow wave coupling decreased from 77.9 ± 3.1% to 69.5 ± 3.1% (P = 0.0078) and from 74.6 ± 2.5% to 68.2 ± 2.8% (P = 0.0054) with the bitter and the salty taste, respectively. Stimulation with sweet, salty, or sour taste evoked a significant decrease in the high frequency component of the HRV, whereas bitter taste did not affect the SPB. CONCLUSIONS Oral stimulation with tastes subjectively perceived as unpleasant brings about disturbances of the interdigestive GMA. This, however, does not coincide with its effect upon SPB.
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Affiliation(s)
- Marek Waluga
- Department of Basic Biomedical Science, School of Pharmacy, Medical University of Silesia, Sosnowiec, Poland
| | - Krzysztof Jonderko
- Department of Basic Biomedical Science, School of Pharmacy, Medical University of Silesia, Sosnowiec, Poland,Address for correspondence: Prof. Krzysztof Jonderko, Department of Basic Biomedical Science, School of Pharmacy, Medical University of Silesia, Sosnowiec, Poland. E-mail:
| | - Ewelina Domosławska
- Department of Basic Biomedical Science, School of Pharmacy, Medical University of Silesia, Sosnowiec, Poland
| | - Anna Matwiejszyn
- Department of Basic Biomedical Science, School of Pharmacy, Medical University of Silesia, Sosnowiec, Poland
| | - Marek Dzielicki
- Department of Basic Biomedical Science, School of Pharmacy, Medical University of Silesia, Sosnowiec, Poland
| | - Beata Krusiec-Świdergoł
- Department of Basic Biomedical Science, School of Pharmacy, Medical University of Silesia, Sosnowiec, Poland
| | - Anna Kasicka-Jonderko
- Department of Basic Biomedical Science, School of Pharmacy, Medical University of Silesia, Sosnowiec, Poland
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Abstract
Obesity is a complex disease with many causal factors, associated with multiple comorbidities that contribute to significant morbidity and mortality. It is a highly prevalent disease that poses an enormous health and economic burden to society. This article reviews the mechanisms of obesity and its related comorbidities.
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Affiliation(s)
- Jagriti Upadhyay
- Section of Endocrinology, Diabetes and Metabolism, Boston VA Healthcare System, 150 South Huntington Avenue, Boston, MA 02130, USA; Division of Endocrinology, Boston Medical Center, Boston University, 88 East Newton Street, Boston, MA 02118; Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA.
| | - Olivia Farr
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA
| | - Nikolaos Perakakis
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA
| | - Wael Ghaly
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA
| | - Christos Mantzoros
- Section of Endocrinology, Diabetes and Metabolism, Boston VA Healthcare System, 150 South Huntington Avenue, Boston, MA 02130, USA; Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA
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Temple JL, Ziegler AM, Graczyk AM, Crandall AK. Reinforcing Value of Caffeinated and Noncaffeinated Beverages After Acute Exposure in Children and Adolescents. JOURNAL OF CAFFEINE RESEARCH 2017; 7:133-141. [PMID: 29230349 DOI: 10.1089/jcr.2017.0015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Background: When caffeine is added to beverages, it increases beverage liking and the relative reinforcing value (RRV) of these beverages after repeated exposure. The purpose of this study was to test the hypothesis that a single acute exposure to caffeine increases liking and motivation to consume sugar-sweetened beverages (SSBs) relative to placebo. Methods: Participants were children ages 8-9 years (n = 36) and adolescents ages 15-17 years (n = 41) with an approximately equal number of boys and girls. A double-blind, placebo-controlled crossover study was conducted where participants sampled a SSB containing caffeine (1 and 2 mg/kg) on one visit and placebo (quinine 0.01 and 0.02 mg/kg) on a second visit day and then, on a third visit, played a computer game to earn points for the beverages and rated liking and taste sensations. They returned to the laboratory after a 1-week washout and had the alternate dose combination. Results: Acute exposure to the higher dose of caffeine increased the RRV of the SSB relative to placebo, but only when that dose was presented in the first week and only in female participants. The liking of the caffeine-containing SSB at the higher dose was lower than the placebo at all time points. Conclusions: These data suggest that a single exposure to a caffeinated SSB can impact its RRV and liking, but only under certain conditions and only in females. This supports previous work suggesting that caffeine can increase desire to consume SSB.
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Affiliation(s)
- Jennifer L Temple
- Department of Exercise and Nutrition Sciences, School of Public Health and Health Professions, University at Buffalo, Buffalo, New York.,Department of Community Health and Health Behavior, School of Public Health and Health Professions, University at Buffalo, Buffalo, New York
| | - Amanda M Ziegler
- Department of Exercise and Nutrition Sciences, School of Public Health and Health Professions, University at Buffalo, Buffalo, New York
| | - Adam M Graczyk
- Department of Community Health and Health Behavior, School of Public Health and Health Professions, University at Buffalo, Buffalo, New York
| | - Amanda K Crandall
- Department of Community Health and Health Behavior, School of Public Health and Health Professions, University at Buffalo, Buffalo, New York
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48
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Morales I, Currie PJ, Hackenberg TD, Pastor R. Opioidergic and dopaminergic modulation of cost/benefit decision-making in Long Evans Rats. Physiol Behav 2017; 179:442-450. [DOI: 10.1016/j.physbeh.2017.07.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 07/12/2017] [Accepted: 07/12/2017] [Indexed: 10/19/2022]
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49
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Feeding Releases Endogenous Opioids in Humans. J Neurosci 2017; 37:8284-8291. [PMID: 28747384 DOI: 10.1523/jneurosci.0976-17.2017] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 07/06/2017] [Accepted: 07/10/2017] [Indexed: 11/21/2022] Open
Abstract
The endogenous opioid system supports a multitude of functions related to appetitive behavior in humans and animals, and it has been proposed to govern hedonic aspects of feeding thus contributing to the development of obesity. Here we used positron emission tomography to investigate whether feeding results in hedonia-dependent endogenous opioid release in humans. Ten healthy males were recruited for the study. They were scanned with the μ-opioid-specific ligand [11C]carfentanil three times, as follows: after a palatable meal, a nonpalatable meal, and after an overnight fast. Subjective mood, satiety, and circulating hormone levels were measured. Feeding induced significant endogenous opioid release throughout the brain. This response was more pronounced following a nonpalatable meal versus a palatable meal, and independent of the subjective hedonic responses to feeding. We conclude that feeding consistently triggers cerebral opioid release even in the absence of subjective pleasure associated with feeding, suggesting that metabolic and homeostatic rather than exclusively hedonic responses play a role in the feeding-triggered cerebral opioid release.SIGNIFICANCE STATEMENT The endogenous opioid system supports both hedonic and homeostatic functions. It has been proposed that overeating and concomitant opioid release could downregulate opioid receptors and promote the development of obesity. However, it remains unresolved whether feeding leads to endogenous opioid release in humans. We used in vivo positron emission tomography to test whether feeding triggers cerebral opioid release and whether this response is associated with pleasurable sensations. We scanned volunteers using the μ-opioid receptor-specific radioligand [11C]carfentanil three times, as follows: after an overnight fast, after consuming a palatable meal, and after consuming a nonpalatable meal. Feeding led to significant endogenous opioid release, and this occurred also in the absence of feeding-triggered hedonia. Feeding-triggered opioid release thus also reflects metabolic and homeostatic responses rather than hedonic responses exclusively.
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