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Iovino M, Messana T, Marucci S, Triggiani D, Giagulli VA, Guastamacchia E, Piazzolla G, De Pergola G, Lisco G, Triggiani V. The neurohypophyseal hormone oxytocin and eating behaviors: a narrative review. Hormones (Athens) 2024; 23:15-23. [PMID: 37979096 PMCID: PMC10847364 DOI: 10.1007/s42000-023-00505-y] [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: 05/17/2023] [Accepted: 11/03/2023] [Indexed: 11/19/2023]
Abstract
BACKGROUND The neuropeptide oxytocin (OT) is crucial in several conditions, such as lactation, parturition, mother-infant interaction, and psychosocial function. Moreover, OT may be involved in the regulation of eating behaviors. METHODS This review briefly summarizes data concerning the role of OT in eating behaviors. Appropriate keywords and medical subject headings were identified and searched for in PubMed/MEDLINE. References of original articles and reviews were screened, examined, and selected. RESULTS Hypothalamic OT-secreting neurons project to different cerebral areas controlling eating behaviors, such as the amygdala, area postrema, nucleus of the solitary tract, and dorsal motor nucleus of the vagus nerve. Intracerebral/ventricular OT administration decreases food intake and body weight in wild and genetically obese rats. OT may alter food intake and the quality of meals, especially carbohydrates and sweets, in humans. DISCUSSION OT may play a role in the pathophysiology of eating disorders with potential therapeutic perspectives. In obese patients and those with certain eating disorders, such as bulimia nervosa or binge/compulsive eating, OT may reduce appetite and caloric consumption. Conversely, OT administered to patients with anorexia nervosa may paradoxically stimulate appetite, possibly by lowering anxiety which usually complicates the management of these patients. Nevertheless, OT administration (e.g., intranasal route) is not always associated with clinical benefit, probably because intranasally administered OT fails to achieve therapeutic intracerebral levels of the hormone. CONCLUSION OT administration could play a therapeutic role in managing eating disorders and disordered eating. However, specific studies are needed to clarify this issue with regard to dose-finding and route and administration time.
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Affiliation(s)
- Michele Iovino
- Interdisciplinary Department of Medicine, Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari "Aldo Moro", School of Medicine, Bari, Apulia, Italy
| | - Tullio Messana
- Infantile Neuropsychiatry, IRCCS - Institute of Neurological Sciences, Bologna, Italy
| | - Simonetta Marucci
- Università Campus Biomedico, Dip. "Scienze e Tecnologie per l'Uomo e l'ambiente", Via Alvaro del Portillo, 21, Roma, Italy
| | - Domenico Triggiani
- Interdisciplinary Department of Medicine, Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari "Aldo Moro", School of Medicine, Bari, Apulia, Italy
| | - Vito Angelo Giagulli
- Interdisciplinary Department of Medicine, Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari "Aldo Moro", School of Medicine, Bari, Apulia, Italy
| | - Edoardo Guastamacchia
- Interdisciplinary Department of Medicine, Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari "Aldo Moro", School of Medicine, Bari, Apulia, Italy
| | - Giuseppina Piazzolla
- Interdisciplinary Department of Medicine, Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari "Aldo Moro", School of Medicine, Bari, Apulia, Italy
| | - Giovanni De Pergola
- National Institute of Gastroenterology IRCCS "Saverio de Bellis", Research Hospital, Castellana Grotte, Bari, Italy
- Department of Biomedical Science and Human Oncology, University of Bari, School of Medicine, Bari, Apulia, Italy
| | - Giuseppe Lisco
- Interdisciplinary Department of Medicine, Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari "Aldo Moro", School of Medicine, Bari, Apulia, Italy.
| | - Vincenzo Triggiani
- Interdisciplinary Department of Medicine, Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari "Aldo Moro", School of Medicine, Bari, Apulia, Italy
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Zhang Y, Huang W, Shan Z, Zhou Y, Qiu T, Hu L, Yang L, Wang Y, Xiao Z. A new experimental rat model of nocebo-related nausea involving double mechanisms of observational learning and conditioning. CNS Neurosci Ther 2024; 30:e14389. [PMID: 37545429 PMCID: PMC10848046 DOI: 10.1111/cns.14389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/12/2023] [Accepted: 07/23/2023] [Indexed: 08/08/2023] Open
Abstract
AIM The nocebo effect, such as nausea and vomiting, is one of the major reasons patients discontinue therapy. The underlying mechanisms remain unknown due to a lack of reliable experimental models. The goal of this study was to develop a new animal model of nocebo-related nausea by combining observational learning and Pavlovian conditioning paradigms. METHODS Male Sprague-Dawley rats with nitroglycerin-induced migraine were given 0.9% saline (a placebo) or LiCl (a nausea inducer) following headache relief, according to different paradigms. RESULTS Both strategies provoked nocebo nausea responses, with the conditioning paradigm having a greater induction impact. The superposition of two mechanisms led to a further increase in nausea responses. A preliminary investigation of the underlying mechanism revealed clearly raised peripheral and central cholecystokinin (CCK) levels, as well as specific changes in the 5-hydroxytryptamine and cannabinoid systems. Brain networks related to emotion, cognition, and visceral sense expressed higher c-Fos-positive neurons, including the anterior cingulate cortex (ACC), insula, basolateral amygdala (BLA), thalamic paraventricular nucleus (PVT), hypothalamic paraventricular nucleus (PVN), nucleus tractus solitarius (NTS), periaqueductal gray (PAG), and dorsal raphe nucleus-dorsal part (DRD). We also found that nausea expectances in the model could last for at least 12 days. CONCLUSION The present study provides a useful experimental model of nocebo nausea that might be used to develop potential molecular pathways and therapeutic strategies for nocebo.
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Affiliation(s)
- Yu Zhang
- Department of NeurologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
- Central LaboratoryRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Wanbin Huang
- Department of NeurologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
- Central LaboratoryRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Zhengming Shan
- Department of NeurologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
- Central LaboratoryRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Yanjie Zhou
- Department of NeurologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
- Central LaboratoryRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Tao Qiu
- Department of NeurologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Luyu Hu
- Department of NeurologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Liu Yang
- Department of NeurologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Yue Wang
- Department of NeurologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Zheman Xiao
- Department of NeurologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
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Ikeda N, Kawasaki M, Baba K, Nishimura H, Fujitani T, Suzuki H, Matsuura T, Ohnishi H, Shimizu M, Sanada K, Nishimura K, Yoshimura M, Maruyama T, Conway-Campbell BL, Onaka T, Teranishi H, Hanada R, Ueta Y, Sakai A. Chemogenetic Activation of Oxytocin Neurons Improves Pain in a Reserpine-induced Fibromyalgia Rat Model. Neuroscience 2023; 528:37-53. [PMID: 37532013 DOI: 10.1016/j.neuroscience.2023.07.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 07/20/2023] [Accepted: 07/25/2023] [Indexed: 08/04/2023]
Abstract
Fibromyalgia (FM) is a syndrome characterized by chronic pain with depression as a frequent comorbidity. However, efficient management of the pain and depressive symptoms of FM is lacking. Given that endogenous oxytocin (OXT) contributes to the regulation of pain and depressive disorders, herein, we investigated the role of OXT in an experimental reserpine-induced FM model. In FM model, OXT-monomeric red fluorescent protein 1 (OXT-mRFP1) transgenic rats exhibited increased depressive behavior and sensitivity in a mechanical nociceptive test, suggesting reduced pain tolerance. Additionally, the development of the FM-like phenotype in OXT-mRFP1 FM model rats was accompanied by a significant reduction in OXT mRNA expression in the magnocellular neurons of the paraventricular nucleus. OXT-mRFP1 FM model rats also had significantly fewer tryptophan hydroxylase (TPH)- and tyrosine hydroxylase (TH)-immunoreactive (ir) neurons as well as reduced serotonin and norepinephrine levels in the dorsal raphe and locus coeruleus. To investigate the effects of stimulating the endogenous OXT pathway, rats expressing OXT-human muscarinic acetylcholine receptor (hM3Dq)-mCherry designer receptors exclusively activated by designer drugs (DREADDs) were also assessed in the FM model. Treatment of these rats with clozapine-N-oxide (CNO), an hM3Dq-activating drug, significantly improved characteristic FM model-induced pathophysiological pain, but did not alter depressive-like behavior. The chemogenetically induced effects were reversed by pre-treatment with an OXT receptor antagonist, confirming the specificity of action via the OXT pathway. These results indicate that endogenous OXT may have analgesic effects in FM, and could be a potential target for effective pain management strategies for this disorder.
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Affiliation(s)
- Naofumi Ikeda
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Makoto Kawasaki
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
| | - Kazuhiko Baba
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Haruki Nishimura
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Teruaki Fujitani
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Hitoshi Suzuki
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Takanori Matsuura
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Hideo Ohnishi
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Makiko Shimizu
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Kenya Sanada
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Kazuaki Nishimura
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Mitsuhiro Yoshimura
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Takashi Maruyama
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | | | - Tatsushi Onaka
- Division of Brain and Neurophysiology, Department of Physiology, Jichi Medical University, Shimotsuke, Japan
| | - Hitoshi Teranishi
- Department of Neurophysiology, Faculty of Medicine, Oita University, Yufu, Japan
| | - Reiko Hanada
- Department of Neurophysiology, Faculty of Medicine, Oita University, Yufu, Japan
| | - Yoichi Ueta
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Akinori Sakai
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
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Aulinas A, Muhammed M, Becker KR, Asanza E, Hauser K, Stern C, Gydus J, Holmes T, Murray HB, Breithaupt L, Micali N, Misra M, Eddy KT, Thomas JJ, Lawson EA. Oxytocin response to food intake in avoidant/restrictive food intake disorder. Eur J Endocrinol 2023; 189:149-155. [PMID: 37474111 PMCID: PMC10396082 DOI: 10.1093/ejendo/lvad087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/16/2023] [Accepted: 06/07/2023] [Indexed: 07/22/2023]
Abstract
OBJECTIVE To investigate the response of anorexigenic oxytocin to food intake among adolescents and young adults with avoidant/restrictive food intake disorder (ARFID), a restrictive eating disorder characterized by lack of interest in food or eating, sensory sensitivity to food, and/or fear of aversive consequences of eating, compared with healthy controls (HC). DESIGN Cross-sectional. METHODS A total of 109 participants (54 with ARFID spectrum and 55 HC) were instructed to eat a ∼400-kcal standardized mixed meal. We sampled serum oxytocin at fasting and at 30-, 60-, and 120-min postmeal. We tested the hypothesis that ARFID would show higher mean oxytocin levels across time points compared with HC using a mixed model ANOVA. We then used multivariate regression analysis to identify the impact of clinical characteristics (sex, age, and body mass index [BMI] percentile) on oxytocin levels in individuals with ARFID. RESULTS Participants with ARFID exhibited greater mean oxytocin levels at all time points compared with HC, and these differences remained significant even after controlling for sex and BMI percentile (P = .004). Clinical variables (sex, age, and BMI percentile) did not show any impact on fasting and postprandial oxytocin levels among individuals with ARFID. CONCLUSIONS Consistently high oxytocin levels might be involved in low appetite and sensory aversions to food, contributing to food avoidance in individuals with ARFID.
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Affiliation(s)
- Anna Aulinas
- Department of Endocrinology and Nutrition, Hospital de la Santa Creu i Sant Pau, IIB-Sant Pau, 08041 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER Unidad 747), ISCIII, 08025 Barcelona, Spain
- Department of Medicine, University of Vic—Central University of Catalonia, 08500 Vic, Barcelona, Spain
| | - Maged Muhammed
- Neuroendocrine Unit, Division of Endocrinology, Department of Medicine, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Kendra R Becker
- Department of Medicine, Harvard Medical School, 02115 Boston, MA, United States
- Eating Disorders Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Elisa Asanza
- Neuroendocrine Unit, Division of Endocrinology, Department of Medicine, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Kristine Hauser
- Neuroendocrine Unit, Division of Endocrinology, Department of Medicine, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Casey Stern
- Neuroendocrine Unit, Division of Endocrinology, Department of Medicine, Massachusetts General Hospital, 02114 Boston, MA, United States
- Eating Disorders Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Julia Gydus
- Neuroendocrine Unit, Division of Endocrinology, Department of Medicine, Massachusetts General Hospital, 02114 Boston, MA, United States
- Eating Disorders Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Tara Holmes
- Translational and Clinical Research Center, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Helen Burton Murray
- Department of Medicine, Harvard Medical School, 02115 Boston, MA, United States
- Center for Neurointestinal Health, Division of Gastroenterology, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Lauren Breithaupt
- Department of Medicine, Harvard Medical School, 02115 Boston, MA, United States
- Eating Disorders Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Nadia Micali
- Eating Disorders Research Unit, Mental Health Services of the Capital Region of Denmark, Psychiatric Centre Ballerup, 2750 Ballerup, Denmark
- Population, Policy and Practice, Great Ormond Street Institute of Child Health, University College London, WC1N 1EH, London, United Kingdom
| | - Madhusmita Misra
- Neuroendocrine Unit, Division of Endocrinology, Department of Medicine, Massachusetts General Hospital, 02114 Boston, MA, United States
- Department of Medicine, Harvard Medical School, 02115 Boston, MA, United States
- Division of Pediatric Endocrinology, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Kamryn T Eddy
- Department of Medicine, Harvard Medical School, 02115 Boston, MA, United States
- Eating Disorders Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Jennifer J Thomas
- Department of Medicine, Harvard Medical School, 02115 Boston, MA, United States
- Eating Disorders Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, 02114 Boston, MA, United States
| | - Elizabeth A Lawson
- Neuroendocrine Unit, Division of Endocrinology, Department of Medicine, Massachusetts General Hospital, 02114 Boston, MA, United States
- Department of Medicine, Harvard Medical School, 02115 Boston, MA, United States
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5
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Asker M, Krieger JP, Liles A, Tinsley IC, Borner T, Maric I, Doebley S, Furst CD, Börchers S, Longo F, Bhat YR, De Jonghe BC, Hayes MR, Doyle RP, Skibicka KP. Peripherally restricted oxytocin is sufficient to reduce food intake and motivation, while CNS entry is required for locomotor and taste avoidance effects. Diabetes Obes Metab 2023; 25:856-877. [PMID: 36495318 PMCID: PMC9987651 DOI: 10.1111/dom.14937] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 11/21/2022] [Accepted: 12/02/2022] [Indexed: 12/14/2022]
Abstract
OBJECTIVES Oxytocin (OT) has a well-established role in reproductive behaviours; however, it recently emerged as an important regulator of energy homeostasis. In addition to central nervous system (CNS), OT is found in the plasma and OT receptors (OT-R) are found in peripheral tissues relevant to energy balance regulation. Here, we aim to determine whether peripheral OT-R activation is sufficient to alter energy intake and expenditure. METHODS AND RESULTS We first show that systemic OT potently reduced food intake and food-motivated behaviour for a high-fat reward in male and female rats. As it is plausible that peripherally, intraperitoneally (IP) injected OT crosses the blood-brain barrier (BBB) to produce some of the metabolic effects within the CNS, we screened, with a novel fluorescently labelled-OT (fAF546-OT, Roxy), for the presence of IP-injected Roxy in CNS tissue relevant to feeding control and compared such with BBB-impermeable fluorescent OT-B12 (fCy5-OT-B12; BRoxy). While Roxy did penetrate the CNS, BRoxy did not. To evaluate the behavioural and thermoregulatory impact of exclusive activation of peripheral OT-R, we generated a novel BBB-impermeable OT (OT-B12 ), with equipotent binding at OT-R in vitro. In vivo, IP-injected OT and OT-B12 were equipotent at food intake suppression in rats of both sexes, suggesting that peripheral OT acts on peripheral OT-R to reduce feeding behaviour. Importantly, OT induced a potent conditioned taste avoidance, indistinguishable from that induced by LiCl, when applied peripherally. Remarkably, and in contrast to OT, OT-B12 did not induce any conditioned taste avoidance. Limiting the CNS entry of OT also resulted in a dose-dependent reduction of emesis in male shrews. While both OT and OT-B12 proved to have similar effects on body temperature, only OT resulted in home-cage locomotor depression. CONCLUSIONS Together our data indicate that limiting systemic OT CNS penetrance preserves the anorexic effects of the peptide and reduces the clinically undesired side effects of OT: emesis, taste avoidance and locomotor depression. Thus, therapeutic targeting of peripheral OT-R may be a viable strategy to achieve appetite suppression with better patient outcomes.
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Affiliation(s)
- Mohammed Asker
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Wallenberg Centre for molecular and translational medicine, University of Gothenburg, Gothenburg, Sweden
| | - Jean-Philippe Krieger
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Amber Liles
- Department of Chemistry, Syracuse University, Syracuse, New York, USA
| | - Ian C Tinsley
- Department of Chemistry, Syracuse University, Syracuse, New York, USA
| | - Tito Borner
- Department of Biobehavioral Health Sciences, University of Pennsylvania, School of Nursing, Philadelphia, Pennsylvania, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ivana Maric
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Department of Chemistry, Syracuse University, Syracuse, New York, USA
- Department of Nutritional Sciences, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Sarah Doebley
- Department of Biobehavioral Health Sciences, University of Pennsylvania, School of Nursing, Philadelphia, Pennsylvania, USA
| | - C Daniel Furst
- Department of Biobehavioral Health Sciences, University of Pennsylvania, School of Nursing, Philadelphia, Pennsylvania, USA
| | - Stina Börchers
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Wallenberg Centre for molecular and translational medicine, University of Gothenburg, Gothenburg, Sweden
| | - Francesco Longo
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Yashaswini R Bhat
- Department of Nutritional Sciences, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Bart C De Jonghe
- Department of Biobehavioral Health Sciences, University of Pennsylvania, School of Nursing, Philadelphia, Pennsylvania, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Matthew R Hayes
- Department of Biobehavioral Health Sciences, University of Pennsylvania, School of Nursing, Philadelphia, Pennsylvania, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Robert P Doyle
- Department of Chemistry, Syracuse University, Syracuse, New York, USA
- Departments of Medicine and Pharmacology, State University of New York, Upstate Medical University, Syracuse, New York, USA
| | - Karolina P Skibicka
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Wallenberg Centre for molecular and translational medicine, University of Gothenburg, Gothenburg, Sweden
- Department of Nutritional Sciences, Pennsylvania State University, University Park, Pennsylvania, USA
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Oxytocin and Food Intake Control: Neural, Behavioral, and Signaling Mechanisms. Int J Mol Sci 2021; 22:ijms221910859. [PMID: 34639199 PMCID: PMC8509519 DOI: 10.3390/ijms221910859] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 09/29/2021] [Accepted: 10/03/2021] [Indexed: 11/16/2022] Open
Abstract
The neuropeptide oxytocin is produced in the paraventricular hypothalamic nucleus and the supraoptic nucleus of the hypothalamus. In addition to its extensively studied influence on social behavior and reproductive function, central oxytocin signaling potently reduces food intake in both humans and animal models and has potential therapeutic use for obesity treatment. In this review, we highlight rodent model research that illuminates various neural, behavioral, and signaling mechanisms through which oxytocin’s anorexigenic effects occur. The research supports a framework through which oxytocin reduces food intake via amplification of within-meal physiological satiation signals rather than by altering between-meal interoceptive hunger and satiety states. We also emphasize the distributed neural sites of action for oxytocin’s effects on food intake and review evidence supporting the notion that central oxytocin is communicated throughout the brain, at least in part, through humoral-like volume transmission. Finally, we highlight mechanisms through which oxytocin interacts with various energy balance-associated neuropeptide and endocrine systems (e.g., agouti-related peptide, melanin-concentrating hormone, leptin), as well as the behavioral mechanisms through which oxytocin inhibits food intake, including effects on nutrient-specific ingestion, meal size control, food reward-motivated responses, and competing motivations.
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7
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Harshaw C, Lanzkowsky J, Tran AQD, Bradley AR, Jaime M. Oxytocin and 'social hyperthermia': Interaction with β 3-adrenergic receptor-mediated thermogenesis and significance for the expression of social behavior in male and female mice. Horm Behav 2021; 131:104981. [PMID: 33878523 DOI: 10.1016/j.yhbeh.2021.104981] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 04/02/2021] [Accepted: 04/03/2021] [Indexed: 02/07/2023]
Abstract
Oxytocin (OT) is a critical regulator of multiple facets of energy homeostasis, including brown adipose tissue (BAT) thermogenesis. Nevertheless, it is unclear what, if any, consequence the thermoregulatory and metabolic effects of OT have for the display of social behavior in adult rodents. Here, we examine the contribution of the OT receptor (OTR) and β3 adrenergic receptor (β3AR) to the increase in body temperature that typically accompanies social interaction (i.e., social hyperthermia; SH) and whether SH relates to the expression of social behavior in adult mice. Specifically, we examined how OTR antagonism via peripheral injection of L-368,899 (10 mg/kg) affects the expression of social behavior in C57BL/6J mice, in the presence of active/agonized versus antagonized β3AR, the receptor known to mediate stress-induced BAT thermogenesis. After drug treatment and a 30 min delay, mice were provided a 10 min social interaction test with an unfamiliar, same-sex conspecific. We hypothesized that OTR and β3AR/BAT interact to influence behavior during social interaction, with at least some effects of OT on social behavior dependent upon OT's thermal effects via β3AR/BAT. We found that OTR-mediated temperature elevation is largely responsible for SH during social interaction in mice-albeit not substantially via β3AR-dependent BAT thermogenesis. Further, our results reveal a complex relationship between OTR, β3AR, social hyperthermia and the display of specific social behaviors, with SH most closely associated with anxiety and/or vigilance-related behaviors-that is, behaviors that antagonize or interfere with the initiation of close, non-agonistic social behavior.
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Affiliation(s)
- Christopher Harshaw
- Department of Psychology, University of New Orleans, New Orleans, LA, United States of America.
| | - Jessica Lanzkowsky
- Department of Psychology, University of New Orleans, New Orleans, LA, United States of America
| | | | - Alana Rose Bradley
- Department of Psychology, University of New Orleans, New Orleans, LA, United States of America
| | - Mark Jaime
- Division of Science, Indiana University-Purdue University, Columbus, Columbus, IN, United States of America
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8
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Haskal de la Zerda S, Netser S, Magalnik H, Wagner S. Impaired sex preference, but not social and social novelty preferences, following systemic blockade of oxytocin receptors in adult male mice. Psychoneuroendocrinology 2020; 116:104676. [PMID: 32361188 DOI: 10.1016/j.psyneuen.2020.104676] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 02/23/2020] [Accepted: 03/25/2020] [Indexed: 01/14/2023]
Abstract
The hypothalamic neuropeptide oxytocin (OT) is a powerful modulator of mammalian social behavior and its administration was shown to affect various types of social interactions. However, systematic examinations of the role of endogenous OT release in social behavior have heretofore been done only using genetically modified animal models in which the genes encoding either OT or the OT receptor (OTR) were mutated. While such genetic manipulations revealed various behavioral deficits, these deficits may involve developmental or long-term processes and do not prove the participation of acute OT release in the impaired behavior. Here we used a battery of social discrimination tasks to evaluate the effects of acute systemic OTR blockade, using a non-peptide, orally active OTR antagonist (L368,899), on social behavior of adult male C57BL/6 J mice. We found no effect of the pharmacological manipulation on the social preference and social novelty preference behaviors. However, the preference of a male mouse for investigating a female conspecific more than a male (sex preference behavior), was lost by administration of the OTR antagonist. Finally, we found that blocking OTR activity before social defeat prevented the consequent loss of social preference, suggesting a role for OT in the acquisition of aversive social memory. Overall, our results suggest that OT plays a role in modulating the salience of social stimuli and facilitating their memory, as predicted by the social salience theory, rather than in regulating the internal motivation of the subject for social interactions.
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Affiliation(s)
- Shani Haskal de la Zerda
- Sagol Department of Neurobiology, The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, Haifa 3498838, Israel
| | - Shai Netser
- Sagol Department of Neurobiology, The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, Haifa 3498838, Israel
| | - Hen Magalnik
- Sagol Department of Neurobiology, The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, Haifa 3498838, Israel
| | - Shlomo Wagner
- Sagol Department of Neurobiology, The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, Haifa 3498838, Israel.
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9
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Lawson EA, Olszewski PK, Weller A, Blevins JE. The role of oxytocin in regulation of appetitive behaviour, body weight and glucose homeostasis. J Neuroendocrinol 2020; 32:e12805. [PMID: 31657509 PMCID: PMC7186135 DOI: 10.1111/jne.12805] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/14/2019] [Accepted: 10/24/2019] [Indexed: 12/28/2022]
Abstract
Obesity and its associated complications have reached epidemic proportions in the USA and also worldwide, highlighting the need for new and more effective treatments. Although the neuropeptide oxytocin (OXT) is well recognised for its peripheral effects on reproductive behaviour, the release of OXT from somatodendrites and axonal terminals within the central nervous system (CNS) is also implicated in the control of energy balance. In this review, we summarise historical data highlighting the effects of exogenous OXT as a short-term regulator of food intake in a context-specific manner and the receptor populations that may mediate these effects. We also describe what is known about the physiological role of endogenous OXT in the control of energy balance and whether serum and brain levels of OXT relate to obesity on a consistent basis across animal models and humans with obesity. We describe recent data on the effectiveness of chronic CNS administration of OXT to decrease food intake and weight gain or to elicit weight loss in diet-induced obese (DIO) and genetically obese mice and rats. Of clinical importance is the finding that chronic central and peripheral OXT treatments both evoke weight loss in obese animal models with impaired leptin signalling at doses that are not associated with visceral illness, tachyphylaxis or adverse cardiovascular effects. Moreover, these results have been largely recapitulated following chronic s.c. or intranasal treatment in DIO non-human primates (rhesus monkeys) and obese humans, respectively. We also identify plausible mechanisms that contribute to the effects of OXT on body weight and glucose homeostasis in rodents, non-human primates and humans. We conclude by describing the ongoing challenges that remain before OXT-based therapeutics can be used as a long-term strategy to treat obesity in humans.
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Affiliation(s)
- Elizabeth A Lawson
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Pawel K Olszewski
- Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
- Department of Integrative Biology and Physiology, Medical School, University of Minnesota, Minneapolis, MN, USA
| | - Aron Weller
- Psychology Department and Gonda Brain Research Center, Bar Ilan University, Ramat-Gan, Israel
| | - James E Blevins
- Department of Veterans Affairs Medical Center, Office of Research and Development Medical Research Service, VA Puget Sound Health Care System, Seattle, WA, USA
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA
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10
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Burmester V, Gibson EL, Butler G, Bailey A, Terry P. Oxytocin reduces post-stress sweet snack intake in women without attenuating salivary cortisol. Physiol Behav 2019; 212:112704. [PMID: 31628930 DOI: 10.1016/j.physbeh.2019.112704] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 09/30/2019] [Accepted: 10/07/2019] [Indexed: 10/25/2022]
Abstract
Intranasal oxytocin produces anorectic effects on snack intake in men when tested in the absence of deprivation-induced hunger, but its effects on food intake in women without eating disorders have not been reported. Oxytocin may reduce food intake by reducing stress eating, since it inhibits ACTH release. The present study adopted a double-blind, repeated measures and fully concealed crossover protocol in which 38 women self-administered 24 IU of oxytocin or placebo intranasally, ate lunch, and underwent two consecutive stress tests. Snack intake was assessed 15-20 min after lunch, via a sham taste test. Salivary cortisol was measured throughout the test period every 15 min. Oxytocin significantly reduced sweet fatty snack intake independently of any effect on salivary cortisol, which declined over time at a similar rate after either drug or placebo. Ratings of sweet taste were slightly reduced by oxytocin, but only in self-reported stress eaters. These results differ from previous studies with men that found an effect of oxytocin on postprandial cortisol levels. However, previous research assayed the less active form of plasma cortisol and did not control for protein intake, which can drive elevated cortisol. The finding that oxytocin reduces snack intake in females after acute stress has important implications for appetite regulation and its treatment in obese people and in those with eating disorders.
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Affiliation(s)
- V Burmester
- Department of Psychology, School of Law, Social and Behavioural Sciences, Kingston University, Penrhyn Road, Kingston upon Thames, Surrey KT1 2EE, UK
| | - E L Gibson
- Department of Psychology, Whitelands College, University of Roehampton, London SW15 4JD, UK
| | - G Butler
- Department of Psychology, School of Law, Social and Behavioural Sciences, Kingston University, Penrhyn Road, Kingston upon Thames, Surrey KT1 2EE, UK
| | - A Bailey
- Institute of Medical and Biomedical Education, St George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - P Terry
- Department of Psychology, School of Law, Social and Behavioural Sciences, Kingston University, Penrhyn Road, Kingston upon Thames, Surrey KT1 2EE, UK.
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11
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Leonzino M, Ponzoni L, Braida D, Gigliucci V, Busnelli M, Ceresini I, Duque-Wilckens N, Nishimori K, Trainor BC, Sala M, Chini B. Impaired approach to novelty and striatal alterations in the oxytocin receptor deficient mouse model of autism. Horm Behav 2019; 114:104543. [PMID: 31220463 DOI: 10.1016/j.yhbeh.2019.06.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 06/12/2019] [Accepted: 06/16/2019] [Indexed: 12/12/2022]
Abstract
Long-standing studies established a role for the oxytocin system in social behavior, social reward, pair bonding and affiliation. Oxytocin receptors, implicated in pathological conditions affecting the social sphere such as autism spectrum disorders, can also modulate cognitive processes, an aspect generally overlooked. Here we examined the effect of acute (pharmacological) or genetic (Oxtr-/-) inactivation of oxytocin receptor-mediated signaling, in male mice, in several cognitive tests. In the novel object recognition test, both oxytocin receptor antagonist treated wild type animals and Oxtr-/- mice lacked the typical preference for novelty. Oxtr-/- mice even preferred the familiar object; moreover, their performance in the Morris water maze did not differ from wild types, suggesting that oxytocin receptor inactivation did not disrupt learning. Because the preference for novel objects could be rescued in Oxtr-/- mice with longer habituation periods, we propose that the loss of novelty preferences following Oxtr inactivation is due to altered processing of novel contextual information. Finally, we observed an increased expression of excitatory synaptic markers in the striatum of Oxtr-/- mice and a greater arborization and higher number of spines/neuron in the dorsolateral area of this structure, which drives habit formation. Our data also indicate a specific reshaping of dorsolateral striatal spines in Oxtr-/- mice after exposure to a novel environment, which might subtend their altered approach to novelty, and support previous work pointing at this structure as an important substrate for autistic behaviors.
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Affiliation(s)
- Marianna Leonzino
- CNR, Institute of Neuroscience, Milan, Italy; Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Luisa Ponzoni
- Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Daniela Braida
- Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | | | - Marta Busnelli
- CNR, Institute of Neuroscience, Milan, Italy; Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | | | - Natalia Duque-Wilckens
- Department of Large Animal Clinical Sciences, Department of Physiology/Neuroscience, Michigan State University, East Lansing, MI, USA
| | - Katsuhiko Nishimori
- Department of Obesity and Internal Inflammation, Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University, Fukushima, Japan
| | - Brian C Trainor
- Psychology Department, University of California, Davis, Davis, CA, USA
| | - Mariaelvina Sala
- CNR, Institute of Neuroscience, Milan, Italy; Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Bice Chini
- CNR, Institute of Neuroscience, Milan, Italy; Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy.
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12
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Onaka T, Takayanagi Y. Role of oxytocin in the control of stress and food intake. J Neuroendocrinol 2019; 31:e12700. [PMID: 30786104 PMCID: PMC7217012 DOI: 10.1111/jne.12700] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 02/12/2019] [Accepted: 02/15/2019] [Indexed: 12/20/2022]
Abstract
Oxytocin neurones in the hypothalamus are activated by stressful stimuli and food intake. The oxytocin receptor is located in various brain regions, including the sensory information-processing cerebral cortex; the cognitive information-processing prefrontal cortex; reward-related regions such as the ventral tegmental areas, nucleus accumbens and raphe nucleus; stress-related areas such as the amygdala, hippocampus, ventrolateral part of the ventromedial hypothalamus and ventrolateral periaqueductal gray; homeostasis-controlling hypothalamus; and the dorsal motor complex controlling intestinal functions. Oxytocin affects behavioural and neuroendocrine stress responses and terminates food intake by acting on the metabolic or nutritional homeostasis system, modulating emotional processing, reducing reward values of food intake, and facilitating sensory and cognitive processing via multiple brain regions. Oxytocin also plays a role in interactive actions between stress and food intake and contributes to adaptive active coping behaviours.
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Affiliation(s)
- Tatsushi Onaka
- Division of Brain and NeurophysiologyDepartment of PhysiologyJichi Medical UniversityShimotsuke‐shiJapan
| | - Yuki Takayanagi
- Division of Brain and NeurophysiologyDepartment of PhysiologyJichi Medical UniversityShimotsuke‐shiJapan
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13
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Oxytocin administration in the basolateral and central nuclei of amygdala moderately suppresses food intake. Neuroreport 2019. [PMID: 29538098 DOI: 10.1097/wnr.0000000000001005] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Oxytocin (OT) at acting central nuclei decreases meal size and reduces intake of palatable sweet solutions. It remains largely unclear as to which brain sites mediate OT's effect on palatability versus energy or the combination of those aspects of consumption. Here, we expanded the search for sites that mediate anorexigenic properties of OT by focusing on two subdivisions of the amygdala, its central (CNA) and basolateral (BLA) nuclei. We injected OT directly into the BLA or CNA in rats and assessed intake of standard chow induced by energy deprivation and intake of sweet solutions in nondeprived animals. We examined whether these effects are reversible by OT receptor (OTr) antagonism and whether OT presence in BLA or CNA induces taste aversion. We also determined the effect of energy deprivation and exposure to sweet saccharin on BLA and CNA expression of OTr mRNA. OT administration in BLA at 0.3 μg and in CNA at 1 μg reduced standard chow intake after deprivation by ~25%. Only administration of OT in BLA was effective in suppressing consumption of sucrose and saccharin solutions. The anorexigenic effects of OT in BLA and CNA were attenuated by OTr antagonist, L-368,899, pretreatment. OT at anorexigenic doses did not promote acquisition of taste aversion. BLA OTr mRNA expression was affected by exposure to palatable saccharin, whereas that of CNA OTr, by energy deprivation. OT in the amygdala moderately decreases food intake. The functional relationship between amygdalar OT and energy intake versus palatability-driven intake depends on the discrete localization of the OTr within this complex structure.
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14
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Kabasakalian A, Ferretti CJ, Hollander E. Oxytocin and Prader-Willi Syndrome. Curr Top Behav Neurosci 2018; 35:529-557. [PMID: 28956320 DOI: 10.1007/7854_2017_28] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In the chapter, we explore the relationship between the peptide hormone, oxytocin (OT), and behavioral and metabolic disturbances observed in the genetic disorder Prader-Willi Syndrome (PWS). Phenotypic and genotypic characteristics of PWS are described, as are the potential implications of an abnormal OT system with respect to neural development including the possible effects of OT dysfunction on interactions with other regulatory mediators, including neurotransmitters, neuromodulators, and hormones. The major behavioral characteristics are explored in the context of OT dysfunction, including hyperphagia, impulsivity, anxiety and emotion dysregulation, sensory processing and interoception, repetitive and restrictive behaviors, and dysfunctional social cognition. Behavioral overlaps with autistic spectrum disorders are discussed. The implications of OT dysfunction on the mechanisms of reward and satiety and their possible role in informing behavioral characteristics are also discussed. Treatment implications and future directions for investigation are considered.
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Affiliation(s)
- Anahid Kabasakalian
- Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, NY, USA
| | - Casara J Ferretti
- Ferkauf Graduate School of Psychology, Yeshiva University, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Eric Hollander
- Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, NY, USA.
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Nagano M, Takumi T, Suzuki H. Critical roles of serotonin-oxytocin interaction during the neonatal period in social behavior in 15q dup mice with autistic traits. Sci Rep 2018; 8:13675. [PMID: 30209293 PMCID: PMC6135829 DOI: 10.1038/s41598-018-32042-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 08/29/2018] [Indexed: 12/01/2022] Open
Abstract
Disturbance of neurotransmitters and neuromodulators is thought to underlie the pathophysiology of autism spectrum disorder (ASD). Studies of 15q dup mouse models of ASD with human 15q11–13 duplication have revealed that restoring serotonin (5-HT) levels can partially reverse ASD-related symptoms in adults. However, it remains unclear how serotonin contributes to the behavioral symptoms of ASD. In contrast, oxytocin (OXT) has been found to involve social and affiliative behaviors. In this study, we examined whether serotonin-OXT interaction during the early postnatal period plays a critical role in the restoration of social abnormality in 15q dup mice. OXT or the 5-HT1A receptor agonist 8OH-DPAT treatment from postnatal day 7 (PD7) to PD21 ameliorated social abnormality in the three-chamber social interaction test in adult 15q dup mice. The effect of 8OH-DPAT was inhibited by blockade of OXT receptors in 15q dup mice. Thus, serotonin-OXT interaction via 5-HT1A receptors plays a critical role in the normal development of social behavior in 15q dup mice. Therefore, targeting serotonin-OXT interaction may provide a novel therapeutic strategy for treatment of ASD.
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Affiliation(s)
- Masatoshi Nagano
- Department of Pharmacology, Graduate School of Medicine, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, Japan
| | - Toru Takumi
- RIKEN Brain Science Institute, Wako, Saitama, 351-0198, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Tokyo, Japan
| | - Hidenori Suzuki
- Department of Pharmacology, Graduate School of Medicine, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, Japan. .,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Tokyo, Japan.
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16
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Grinevich V, Stoop R. Interplay between Oxytocin and Sensory Systems in the Orchestration of Socio-Emotional Behaviors. Neuron 2018; 99:887-904. [DOI: 10.1016/j.neuron.2018.07.016] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 07/02/2018] [Accepted: 07/10/2018] [Indexed: 01/01/2023]
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17
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Duque-Wilckens N, Steinman MQ, Busnelli M, Chini B, Yokoyama S, Pham M, Laredo SA, Hao R, Perkeybile AM, Minie VA, Tan PB, Bales KL, Trainor BC. Oxytocin Receptors in the Anteromedial Bed Nucleus of the Stria Terminalis Promote Stress-Induced Social Avoidance in Female California Mice. Biol Psychiatry 2018; 83:203-213. [PMID: 29066224 PMCID: PMC5743604 DOI: 10.1016/j.biopsych.2017.08.024] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 08/16/2017] [Accepted: 08/29/2017] [Indexed: 11/19/2022]
Abstract
BACKGROUND The neuropeptide oxytocin (OT) is a key regulator of social and emotional behaviors. The effects of OT are context dependent, and it has been proposed that OT increases the salience of both positive and negative social cues. Here we tested whether the bed nucleus of the stria terminalis (BNST) mediates anxiogenic effects of OT. METHODS First, we studied the effects of systemic administration of an OT receptor (OTR) antagonist L-368,899 on social behavior in male and female California mice exposed to social defeat. We examined the effect of L-368,899 on G protein activation and used early growth response factor 1 immunohistochemistry to identify potential sites of OTR action. Finally, we examined the effects of L-368,899 infused in the BNST on behavior. RESULTS A single dose of systemic L-368,899 increased social approach in stressed female mice and decreased social approach in male mice naïve to defeat. L-368,899 prevented OT activation of G proteins and did not activate G proteins in the absence of OT. Intranasal OT, which reduces social approach in female mice but not male mice, increased early growth response factor 1 immunoreactivity in the nucleus accumbens core and anteromedial BNST in female mice but not in male mice. Stressed female mice that received an infusion of L-368,899 into the anteromedial BNST but not the nucleus accumbens core increased social approach and decreased social vigilance responses. CONCLUSIONS Our results suggest that OTR activation in anteromedial BNST induces a vigilance response in which individuals avoid, yet attend to, unfamiliar social contexts. Our results suggest that OTR antagonists may have unappreciated therapeutic potential for stress-induced psychiatric disorders.
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Affiliation(s)
| | - Michael Q Steinman
- Molecular, Cellular, and Integrative Physiology Graduate Group, University of California, Davis, Davis, California
| | - Marta Busnelli
- Institute of Neuroscience, National Research Council, Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano Milan, and Humanitas Clinical and Research Center, Rozzano, Italy
| | - Bice Chini
- Institute of Neuroscience, National Research Council, Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano Milan, and Humanitas Clinical and Research Center, Rozzano, Italy
| | - Sae Yokoyama
- Psychology Department, University of California, Davis, Davis, California
| | - Mary Pham
- Psychology Department, University of California, Davis, Davis, California
| | - Sarah A Laredo
- Animal Behavior Graduate Group, University of California, Davis, Davis, California
| | - Rebecca Hao
- Psychology Department, University of California, Davis, Davis, California
| | | | - Vanessa A Minie
- Psychology Department, University of California, Davis, Davis, California
| | - Phillip B Tan
- Psychology Department, University of California, Davis, Davis, California
| | - Karen L Bales
- Psychology Department, University of California, Davis, Davis, California
| | - Brian C Trainor
- Animal Behavior Graduate Group, University of California, Davis, Davis, California; Psychology Department, University of California, Davis, Davis, California.
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18
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Oxytocin, social factors, and the expression of conditioned disgust (anticipatory nausea) in male rats. Behav Pharmacol 2018; 27:718-725. [PMID: 27740965 DOI: 10.1097/fbp.0000000000000271] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Disgust has been proposed to have evolved as a means to rid the body and mouth of noxious substances and toxins, as well as to motivate and facilitate avoidance of contact with disease-causing organisms and infectious materials. Nonemetic species, such as the rat, show distinctive facial expressions, including the gaping reaction, indicative of nausea-based disgust. These conditioned disgust responses can be used to model anticipatory nausea in humans, which is a learned response observed following chemotherapy treatment. As social factors play a role in the modulation and expression of conditioned disgust responses in rats, and the nonapeptide, oxytocin (OT), is involved in the modulation of social behavior, the present study examined the effects of an OT antagonist, L-368 899, on the development and expression of socially mediated conditioned disgust in male rats. When administered 10 min before testing in a distinct context (different from the original conditioning context), L-368 899 (5 mg/kg) significantly decreased gaping behavior in rats that were conditioned with a social partner. LiCl-treated rats administered L-368 899 before testing also showed decreased social initiations toward their social partner. These findings suggest that OT may play a role in the modulation and expression of socially mediated conditioned disgust in rats.
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Abstract
PURPOSE OF REVIEW Laboratory animal experiments have consistently shown that oxytocin causes early termination of food intake, thereby promoting a decrease in body weight in a long term. Recent studies have also assessed some of oxytocin's effects on appetite and energy balance in humans. The present study examines the findings of the key basic research and of the few clinical studies published thus far in the context of potential benefits and challenges stemming from the use of oxytocin in obese patients. RECENT FINDINGS Basic research indicates the involvement of oxytocin in satiety, processing, in reducing a drive to eat for pleasure and because of psychosocial factors. Although the results of clinical studies are very scarce, they suggest that oxytocin administered intranasally in humans decreases energy-induced and reward-induced eating, supports cognitive control of food choices, and improves glucose homeostasis, and its effectiveness may be BMI dependent. SUMMARY Despite the wealth of basic research showing broad anorexigenic effects of oxytocin, clinical studies on oxytocin's therapeutic potential in obesity, are still in their infancy. Future implementation of oxytocin-based pharmacological strategies in controlling energy balance will likely depend on our ability to integrate diverse behavioral and metabolic effects of oxytocin in obesity treatment regimens.
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Affiliation(s)
- Pawel K Olszewski
- aDepartment of Food Science and Nutrition, University of Minnesota, St Paul, Minnesota, USA bDepartment of Biological Sciences, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
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Klockars A, Brunton C, Li L, Levine AS, Olszewski PK. Intravenous administration of oxytocin in rats acutely decreases deprivation-induced chow intake, but it fails to affect consumption of palatable solutions. Peptides 2017; 93:13-19. [PMID: 28460894 DOI: 10.1016/j.peptides.2017.04.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Revised: 04/22/2017] [Accepted: 04/27/2017] [Indexed: 01/03/2023]
Abstract
Despite its limited ability to cross the blood-brain barrier, peripherally administered oxytocin (OT) acutely decreases food intake, most likely via the brainstem and hypothalamic mechanisms. Studies performed to date have focused mainly on the effects of subcutaneous or intraperitoneal OT on the consumption of only solid calorie-dense diets (either standard or high-fat), whereas it is unknown whether, similarly to central OT, peripherally administered peptide reduces intake of calorie-dilute and non-caloric palatable solutions. In this project, we established that 0.1μg/kg intravenous (IV) OT is the lowest anorexigenic dose, decreasing deprivation-induced standard chow intake by ca. 40% in rats and its effect does not stem from aversion. We then used this dose in paradigms in which effects of centrally acting OT ligands on consumption of palatable solutions had been previously reported. We found that IV OT did not change episodic intake of individually presented palatable solutions containing 10% sucrose, 0.1% saccharin, combined 10% sucrose-0.1% saccharin or 4.1%. Intralipid and it failed to affect daily scheduled consumption of a sucrose solution in non-deprived rats. In a two-bottle choice test, IV OT did not shift animals' preference from sucrose to Intralipid. Finally, OT injected IV prior to the simultaneous presentation chow and a sucrose solution in food-deprived rats significantly decreased chow intake, whereas sugar water consumption remained unchanged. We conclude that IV OT reduces deprivation-induced chow intake without causing aversion, but the dose effective in decreasing energy-driven consumption of high-calorie food fails to affect consumption of palatable calorie-dilute solutions.
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Affiliation(s)
- Anica Klockars
- Department of Biological Sciences, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | - Chloe Brunton
- Department of Biological Sciences, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | - Lu Li
- University of Auckland, Waikato Clinical School, Hamilton, 3240 New Zealand
| | - Allen S Levine
- Department of Food Science and Nutrition, University of Minnesota, St Paul, MN, USA
| | - Pawel K Olszewski
- Department of Biological Sciences, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand; Department of Food Science and Nutrition, University of Minnesota, St Paul, MN, USA.
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21
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King CE, Griffin WC, Luderman LN, Kates MM, McGinty JF, Becker HC. Oxytocin Reduces Ethanol Self-Administration in Mice. Alcohol Clin Exp Res 2017; 41:955-964. [PMID: 28212464 PMCID: PMC5404956 DOI: 10.1111/acer.13359] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 02/14/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND Excessive ethanol (EtOH) consumption remains an important health concern and effective treatments are lacking. The central oxytocin system has emerged as a potentially important therapeutic target for alcohol and drug addiction. These studies tested the hypothesis that oxytocin reduces EtOH consumption. METHODS Male C57BL/6J mice were given access to EtOH (20% v/v) using a model of binge-like drinking ("drinking in the dark") that also included the use of lickometer circuits to evaluate the temporal pattern of intake as well as 2-bottle choice drinking in the home cage. In addition, EtOH (12% v/v) and sucrose (5% w/v) self-administration on fixed- and progressive-ratio schedules were also evaluated. A wide range of systemically administered oxytocin doses were tested (0 to 10 mg/kg) in these models. RESULTS Oxytocin (0, 0.3, 1, 3, or 10 mg/kg) dose dependently reduced EtOH consumption (maximal 45% reduction) in the binge drinking model, with lower effective doses having minimal effects on general locomotor activity. Oxytocin's effect was blocked by pretreatment with an oxytocin receptor antagonist, and the pattern of contacts (licks) at the EtOH bottle suggested a reduction in motivation to drink EtOH. Oxytocin decreased 2-bottle choice drinking without altering general fluid intake. Oxytocin also reduced operant responding for EtOH and sucrose in a dose-related manner. However, oxytocin decreased responding and motivation (breakpoint values) for EtOH at doses that did not alter responding for sucrose. CONCLUSIONS These results indicate that oxytocin reduces EtOH consumption in different models of self-administration. The effects are not likely due to a general sedative effect of the neuropeptide. Further, oxytocin reduces motivation for EtOH at doses that do not alter responding for a natural reward (sucrose). While some evidence supports a role for oxytocin receptors in mediating these effects, additional studies are needed to further elucidate underlying mechanisms. Nevertheless, these results support the therapeutic potential of oxytocin as a treatment for alcohol use disorder.
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Affiliation(s)
- Courtney E. King
- Charleston Alcohol Research Center, Departments of Psychiatry and Neuroscience, Medical University of South Carolina & VAMC, Charleston, SC 29425
| | - William C. Griffin
- Charleston Alcohol Research Center, Departments of Psychiatry and Neuroscience, Medical University of South Carolina & VAMC, Charleston, SC 29425
| | - Lauryn N. Luderman
- Charleston Alcohol Research Center, Departments of Psychiatry and Neuroscience, Medical University of South Carolina & VAMC, Charleston, SC 29425
| | - Malcolm M. Kates
- Charleston Alcohol Research Center, Departments of Psychiatry and Neuroscience, Medical University of South Carolina & VAMC, Charleston, SC 29425
| | - Jacqueline F. McGinty
- Charleston Alcohol Research Center, Departments of Psychiatry and Neuroscience, Medical University of South Carolina & VAMC, Charleston, SC 29425
| | - Howard C. Becker
- Charleston Alcohol Research Center, Departments of Psychiatry and Neuroscience, Medical University of South Carolina & VAMC, Charleston, SC 29425
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Herisson FM, Waas JR, Fredriksson R, Schiöth HB, Levine AS, Olszewski PK. Oxytocin Acting in the Nucleus Accumbens Core Decreases Food Intake. J Neuroendocrinol 2016; 28. [PMID: 27114001 DOI: 10.1111/jne.12381] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 01/29/2016] [Accepted: 02/24/2016] [Indexed: 01/15/2023]
Abstract
Central oxytocin (OT) promotes feeding termination in response to homeostatic challenges, such as excessive stomach distension, salt loading and toxicity. OT has also been proposed to affect feeding reward by decreasing the consumption of palatable carbohydrates and sweet tastants. Because the OT receptor (OTR) is expressed in the nucleus accumbens core (AcbC) and shell (AcbSh), a site regulating diverse aspects of eating behaviour, we investigated whether OT acts there to affect appetite in rats. First, we examined whether direct AcbC and AcbSh OT injections affect hunger- and palatability-driven consumption. We found that only AcbC OT infusions decrease deprivation-induced chow intake and reduce the consumption of palatable sucrose and saccharin solutions in nondeprived animals. These effects were abolished by pretreatment with an OTR antagonist, L-368,899, injected in the same site. AcbC OT at an anorexigenic dose did not induce a conditioned taste aversion, which indicates that AcbC OT-driven anorexia is not caused by sickness/malaise. The appetite-specific effect of AcbC OT is supported by the real-time polymerase chain reaction analysis of OTR mRNA in the AcbC, which revealed that food deprivation elevates OTR mRNA expression, whereas saccharin solution intake decreases OTR transcript levels. We also used c-Fos immunohistochemistry as a marker of neuronal activation and found that AcbC OT injection increases activation of the AcbC itself, as well as of two feeding-related sites: the hypothalamic paraventricular and supraoptic nuclei. Finally, considering the fact that OT plays a significant role in social behaviour, we examined whether offering animals a meal in a social setting would modify their hypophagic response to AcbC OT injections. We found that a social context abolishes the anorexigenic effects of AcbC OT. We conclude that OT acting via the AcbC decreases food intake driven by hunger and reward in rats offered a meal in a nonsocial setting.
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Affiliation(s)
- F M Herisson
- Department of Biological Sciences, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | - J R Waas
- Department of Biological Sciences, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | - R Fredriksson
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - H B Schiöth
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - A S Levine
- Department of Food Science and Nutrition, University of Minnesota, St Paul, MN, USA
| | - P K Olszewski
- Department of Biological Sciences, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
- Department of Food Science and Nutrition, University of Minnesota, St Paul, MN, USA
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Leng G, Russell JA. The Peptide Oxytocin Antagonist F-792, When Given Systemically, Does Not Act Centrally in Lactating Rats. J Neuroendocrinol 2016; 28. [PMID: 26497634 PMCID: PMC4982133 DOI: 10.1111/jne.12331] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 10/08/2015] [Accepted: 10/20/2015] [Indexed: 12/24/2022]
Abstract
Oxytocin secreted by nerve terminals in the posterior pituitary has important actions for ensuring a successful outcome of pregnancy: it stimulates uterine contractions that lead to birth and it is essential in the milk-ejection reflex, enabling milk to be expelled from the mammary glands into the mouths of suckling young. Oxytocin also has important actions in the brain: released from dendrites of neurones that innervate the posterior pituitary, oxytocin auto-excites the neurones to fire action potentials in co-ordinated bursts, causing secretion of pulses of oxytocin. Central oxytocin actions are blocked by an oxytocin antagonist given into the brain and, consequently, milk transfer stops. Systemic peptide oxytocin antagonist (atosiban) treatment is used clinically in management of pre-term labour, a major obstetric problem. Hence, it is important to know whether an oxytocin antagonist given peripherally can enter the brain and interfere with central oxytocin actions. In the present study, we tested F792, a peptide oxytocin antagonist. In urethane-anaesthetised suckled rats, we show that the mammary gland responsiveness to oxytocin is blocked by i.v. injections of 7 μg/kg of F792, and the milk-ejection reflex is blocked when F792 is given directly into the brain at a dose of 0.2 μg. To critically test whether F792 given systemically can enter the brain, we recorded the suckling- and oxytocin-induced burst-firing of individual antidromically identified oxytocin neurones in the paraventricular nucleus. Given systemically at 100 μg/kg i.v., F792 acted only peripherally, blocking the milk-ejecting actions of oxytocin, but not the burst-firing of oxytocin neurones during suckling (n = 5 neurones in five rats). Hence, this peptide oxytocin antagonist does not enter the brain from the circulation to interfere with an essential oxytocin function in the brain. Furthermore, the functions of oxytocin in the brain evidently cannot be explored with a systemic peptide antagonist.
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Affiliation(s)
- G Leng
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
| | - J A Russell
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
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Suyama S, Kodaira-Hirano M, Otgon-Uul Z, Ueta Y, Nakata M, Yada T. Fasted/fed states regulate postsynaptic hub protein DYNLL2 and glutamatergic transmission in oxytocin neurons in the hypothalamic paraventricular nucleus. Neuropeptides 2016; 56:115-23. [PMID: 26344333 DOI: 10.1016/j.npep.2015.08.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 08/24/2015] [Accepted: 08/25/2015] [Indexed: 01/07/2023]
Abstract
The neurons in the hypothalamus regulate food intake and energy metabolism on reception of systemic energy states. Accumulating evidences have indicated that synaptic transmission on the hypothalamic neurons is modulated by the metabolic condition related to fasted/fed states, and that this modulation of synaptic plasticity plays a role in regulation of feeding. It has been shown that oxytocin (Oxt) neurons in the paraventricular nucleus (PVN) of the hypothalamus sense and integrate various peripheral and central signals and thereby induce satiety. However, whether metabolic conditions regulate the synaptic transmission on Oxt neurons in PVN remains unclear. The present study examined whether the fasted/fed states regulate synaptic transmission on Oxt neurons in PVN. The miniature excitatory postsynaptic currents (mEPSCs) onto Oxt neurons in PVN were increased under ad lib fed condition compared to 24h fasted condition. Furthermore, the NMDA receptor-mediated EPSC on Oxt neurons was increased under fed, compared to fasted, condition. In Oxt neurons, dynein light chain 2 (DYNLL2), a protein suggested to be implicated in the NMDA receptor trafficking to the postsynaptic site, was increased under fed, compared to fasted, condition. The present results suggest that feeding increases excitatory synaptic input on PVN Oxt neurons via mechanisms involving DYNLL2 upregulation and NMDA receptor-mediated synaptic reorganization.
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Affiliation(s)
- Shigetomo Suyama
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, 3311-1 Yakushiji, Shimotsuke, Tochigi 320-0498, Japan
| | - Misato Kodaira-Hirano
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, 3311-1 Yakushiji, Shimotsuke, Tochigi 320-0498, Japan
| | - Zesemdorj Otgon-Uul
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, 3311-1 Yakushiji, Shimotsuke, Tochigi 320-0498, Japan
| | - Yoichi Ueta
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Masanori Nakata
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, 3311-1 Yakushiji, Shimotsuke, Tochigi 320-0498, Japan
| | - Toshihiko Yada
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, 3311-1 Yakushiji, Shimotsuke, Tochigi 320-0498, Japan; Division of Adaptation Development, Department of Developmental Physiology, National Institute for Physiological Sciences, Okazaki, Aichi 444-8585, Japan.
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Activation of the hypothalamic-pituitary-adrenal axis in lithium-induced conditioned taste aversion learning. Eur J Pharmacol 2015; 768:182-8. [PMID: 26524411 DOI: 10.1016/j.ejphar.2015.10.052] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 10/12/2015] [Accepted: 10/28/2015] [Indexed: 01/21/2023]
Abstract
Intraperitoneal injections (ip) of lithium chloride at large doses induce c-Fos expression in the brain regions implicated in conditioned taste aversion (CTA) learning, and also activate the hypothalamic-pituitary-adrenal (HPA) axis and increase the plasma corticosterone levels in rats. A pharmacologic treatment blunting the lithium-induced c-Fos expression in the brain regions, but not the HPA axis activation, induced CTA formation. Synthetic glucocorticoids at conditioning, but not glucocorticoid antagonist, attenuated the lithium-induced CTA acquisition. The CTA acquisition by ip lithium was not affected by adrenalectomy regardless of basal corticosterone supplement, but the extinction was delayed in the absence of basal corticosterone. Glucocorticoids overloading delayed the extinction memory formation of lithium-induced CTA. ip lithium consistently induced the brain c-Fos expression, the HPA activation and CTA formation regardless of the circadian activation of the HPA axis. Intracerebroventricular (icv) injections of lithium at day time also increased the brain c-Fos expression, activated the HPA axis and induced CTA acquisition. However, icv lithium at night, when the HPA axis shows its circadian activation, did not induce CTA acquisition nor activate the HPA axis, although it increased the brain c-Fos expression. These results suggest that the circadian activation of the HPA axis may affect central, but not peripheral, effect of lithium in CTA learning in rats, and the HPA axis activation may be necessary for the central effect of lithium in CTA formation. Also, glucocorticoids may be required for a better extinction; however, increased glucocorticoids hinder both the acquisition and the extinction of lithium-induced CTA.
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Olszewski PK, Allen K, Levine AS. Effect of oxytocin receptor blockade on appetite for sugar is modified by social context. Appetite 2015; 86:81-7. [DOI: 10.1016/j.appet.2014.10.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 09/23/2014] [Accepted: 10/13/2014] [Indexed: 01/28/2023]
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Abstract
Centrally acting oxytocin (OT) inhibits feeding. Recent evidence suggests a link between OT and control of carbohydrate and saccharin intake, but it is unclear whether OT affects appetite for only carbohydrates, especially sweet ones, or sweet tastants irrespective of their carbohydrate content. Therefore, a blood-brain barrier penetrant OT receptor antagonist, L-368,899, was administered in mice and intake of liquid diets containing carbohydrates sucrose, glucose, fructose, polycose, or cornstarch (CS) or the noncarbohydrate, noncaloric sweetener saccharin was studied in episodic intake paradigms: one in which only one tastant was available and the other in which a choice between a carbohydrate (sucrose, glucose, or fructose) and saccharin was provided. We also used real-time PCR to examine hypothalamic Ot mRNA levels in mice provided short-term access to sucrose, CS, or saccharin. In the no-choice paradigm, L-368,899 increased the intake of all carbohydrates, whereas its effect on saccharin consumption showed only a trend. A 10 times lower dose (0.3 mg/kg) stimulated intake of sucrose than other carbohydrates. In the choice test, a very low 0.1 mg/kg dose of L-368,899 doubled the proportion of sucrose consumption relative to saccharin, but did not affect fructose or glucose preference. Ot gene expression increased after sucrose and CS, but not saccharin exposure compared with the controls; however, a higher level of significance was detected in the sucrose group. We conclude that OT inhibits appetite for carbohydrates. Sucrose consumption considerably enhances Ot gene expression and is particularly sensitive to OT receptor blockade, suggesting a special functional relationship between OT and sugar intake.
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Klockars A, Levine AS, Olszewski PK. Central oxytocin and food intake: focus on macronutrient-driven reward. Front Endocrinol (Lausanne) 2015; 6:65. [PMID: 25972841 PMCID: PMC4412129 DOI: 10.3389/fendo.2015.00065] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Accepted: 04/13/2015] [Indexed: 11/17/2022] Open
Abstract
Centrally acting oxytocin (OT) is known to terminate food consumption in response to excessive stomach distension, increase in salt loading, and presence of toxins. Hypothalamic-hindbrain OT pathways facilitate these aspects of OT-induced hypophagia. However, recent discoveries have implicated OT in modifications of feeding via reward circuits: OT has been found to differentially affect consumption of individual macronutrients in choice and no-choice paradigms. In this mini-review, we focus on presenting and interpreting evidence that defines OT as a key component of mechanisms that reduce eating for pleasure and shape macronutrient preferences. We also provide remarks on challenges in integrating the knowledge on physiological and pathophysiological states in which both OT activity and macronutrient preferences are affected.
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Affiliation(s)
- Anica Klockars
- Department of Biological Sciences, University of Waikato, Hamilton, New Zealand
| | - Allen Stuart Levine
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN, USA
| | - Pawel Karol Olszewski
- Department of Biological Sciences, University of Waikato, Hamilton, New Zealand
- *Correspondence: Pawel Karol Olszewski, Department of Biological Sciences, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand,
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