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Taş BM, Özel G, Azman M, Çakmak Karaer I, Kılıç R. Comparison of Intratympanic Oxytocin and Dexamethasone in Cisplatin Ototoxicity: An Experimental Study. Indian J Otolaryngol Head Neck Surg 2024; 76:3405-3411. [PMID: 39130317 PMCID: PMC11306460 DOI: 10.1007/s12070-024-04701-z] [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: 03/14/2024] [Accepted: 04/08/2024] [Indexed: 08/13/2024] Open
Abstract
Although it is widely used, there is still no valid treatment for ototoxicity caused by the antineoplastic drug cisplatin. In this study, we aimed to investigate the efficacy of intratympanic resveratrol and intratympanic dexamethasone treatment in cisplatin-induced ototoxicity. We also compared intratympanic atosiban (oxytocin antagonist) and oxytocin in cisplatin ototoxicity. In this study, 30 rats (60 ears) were used by separating into 5 groups. Cisplatin, oxytocin, dexamethasone, atosiban and 0.9% NaCl were administered intraperitoneally to all groups separately. Auditory Brainstem Response and Distortion Product Otoacoustic Emission tests were performed on all groups before and 72 h after the procedure. Pre-treatment values were higher than post-treatment values in all groups (p < 0.001). There was no significant prolongation of the post-treatment Auditory Brainstem Response I-IV interval in the oxytocin and dexamethasone groups (p > 0.05). There was no significant decrease in the frequencies of 2832 and 4004 after treatment in the oxytocin and dexamethasone group compared to pre-treatment in Distortion Product Otoacoustic Emission. As a result, it has been shown that intratympanic oxytocin may be an option that can be used in the treatment, although it is not as effective as dexamethasone in preventing cisplatin ototoxicity.
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Affiliation(s)
- Burak Mustafa Taş
- Department of Otorhinolaryngology, Division of Head and Neck Surgery, Kırıkkale University School of Medicine, Kırıkkale, Turkey
| | | | - Musa Azman
- Department of Otorhinolaryngology, Division of Head and Neck Surgery, Kırıkkale University School of Medicine, Kırıkkale, Turkey
| | - Işıl Çakmak Karaer
- Department of Otorhinolaryngology, Division of Head and Neck Surgery, Malatya Training and Research Hospital, Malatya, Turkey
| | - Rahmi Kılıç
- Ankara Training and Research Hospital Otorhinolaryngology Clinic, Ankara, Turkey
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2
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Gruber T, Lechner F, Murat C, Contreras RE, Sanchez-Quant E, Miok V, Makris K, Le Thuc O, González-García I, García-Clave E, Althammer F, Krabichler Q, DeCamp LM, Jones RG, Lutter D, Williams RH, Pfluger PT, Müller TD, Woods SC, Pospisilik JA, Martinez-Jimenez CP, Tschöp MH, Grinevich V, García-Cáceres C. High-calorie diets uncouple hypothalamic oxytocin neurons from a gut-to-brain satiation pathway via κ-opioid signaling. Cell Rep 2023; 42:113305. [PMID: 37864798 PMCID: PMC10636643 DOI: 10.1016/j.celrep.2023.113305] [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: 08/04/2022] [Revised: 08/21/2023] [Accepted: 10/04/2023] [Indexed: 10/23/2023] Open
Abstract
Oxytocin-expressing paraventricular hypothalamic neurons (PVNOT neurons) integrate afferent signals from the gut, including cholecystokinin (CCK), to adjust whole-body energy homeostasis. However, the molecular underpinnings by which PVNOT neurons orchestrate gut-to-brain feeding control remain unclear. Here, we show that mice undergoing selective ablation of PVNOT neurons fail to reduce food intake in response to CCK and develop hyperphagic obesity on a chow diet. Notably, exposing wild-type mice to a high-fat/high-sugar (HFHS) diet recapitulates this insensitivity toward CCK, which is linked to diet-induced transcriptional and electrophysiological aberrations specifically in PVNOT neurons. Restoring OT pathways in diet-induced obese (DIO) mice via chemogenetics or polypharmacology sufficiently re-establishes CCK's anorexigenic effects. Last, by single-cell profiling, we identify a specialized PVNOT neuronal subpopulation with increased κ-opioid signaling under an HFHS diet, which restrains their CCK-evoked activation. In sum, we document a (patho)mechanism by which PVNOT signaling uncouples a gut-brain satiation pathway under obesogenic conditions.
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Affiliation(s)
- Tim Gruber
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany; Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI 49506, USA; Department of Epigenetics, Van Andel Institute, Grand Rapids, MI 49506, USA.
| | - Franziska Lechner
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Cahuê Murat
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Raian E Contreras
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Eva Sanchez-Quant
- Helmholtz Pioneer Campus (HPC), Helmholtz Zentrum München, Neuherberg, Germany
| | - Viktorian Miok
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Konstantinos Makris
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany; Computational Discovery Research, Institute for Diabetes and Obesity (IDO), Helmholtz Diabetes Center (HDC), Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Ophélia Le Thuc
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Ismael González-García
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Elena García-Clave
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | | | - Quirin Krabichler
- Department of Neuropeptide Research in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Lisa M DeCamp
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI 49506, USA
| | - Russell G Jones
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI 49506, USA
| | - Dominik Lutter
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany; Computational Discovery Research, Institute for Diabetes and Obesity (IDO), Helmholtz Diabetes Center (HDC), Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Rhiannan H Williams
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute for Neurogenomics, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Paul T Pfluger
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany; Research Unit NeuroBiology of Diabetes, Helmholtz Zentrum München, 85764 Neuherberg, Germany; Neurobiology of Diabetes, TUM School of Medicine, Technical University Munich, 80333 Munich, Germany
| | - Timo D Müller
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany; Department of Pharmacology and Experimental Therapy, Institute for Experimental and Clinical Pharmacology and Toxicology, Eberhard Karls Hospitals and Clinics, Tübingen, Germany
| | - Stephen C Woods
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, USA
| | - John Andrew Pospisilik
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI 49506, USA; Department of Epigenetics, Van Andel Institute, Grand Rapids, MI 49506, USA
| | - Celia P Martinez-Jimenez
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI 49506, USA; TUM School of Medicine, Technical University of Munich, Munich, Germany
| | - Matthias H Tschöp
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany; Division of Metabolic Diseases, Department of Medicine, Technische Universität, Munich, Germany
| | - Valery Grinevich
- Department of Neuropeptide Research in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany; Center for Neuroinflammation and Cardiometabolic Diseases, Georgia State University, Atlanta, GA, USA.
| | - Cristina García-Cáceres
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany; Medizinische Klinik und Poliklinik IV, Klinikum der Universität, Ludwig-Maximilians-Universität München, 80336 Munich, Germany.
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3
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Affiliation(s)
- Joseph G Verbalis
- Division of Endocrinology and Metabolism, Department of Medicine, Georgetown University, Washington, DC, USA.
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4
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Hassan S, El Baradey H, Madi M, Shebl M, Leng G, Lozic M, Ludwig M, Menzies J, MacGregor D. Measuring oxytocin release in response to gavage: Computational modelling and assay validation. J Neuroendocrinol 2023; 35:e13303. [PMID: 37316906 PMCID: PMC10909523 DOI: 10.1111/jne.13303] [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: 01/11/2023] [Revised: 04/18/2023] [Accepted: 04/28/2023] [Indexed: 06/16/2023]
Abstract
In the present experiments, we tested the conclusion from previous electrophysiological experiments that gavage of sweet food and systemically applied insulin both stimulate oxytocin secretion. To do so, we measured oxytocin secretion from urethane-anaesthetised male rats, and demonstrated a significant increase in secretion in response to gavage of sweetened condensed milk but not isocaloric cream, and a significant increase in response to intravenous injection of insulin. We compared the measurements made in response to sweetened condensed milk with the predictions from a computational model, which we used to predict plasma concentrations of oxytocin from the published electrophysiological responses of oxytocin cells. The prediction from the computational model was very closely aligned to the levels of oxytocin measured in rats in response to gavage.
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Affiliation(s)
- Shereen Hassan
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
- Department of Medical Physiology, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Hala El Baradey
- Department of Medical Physiology, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Mohamed Madi
- Department of Medical Physiology, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Mohamed Shebl
- Department of Medical Physiology, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Gareth Leng
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Maja Lozic
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Mike Ludwig
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - John Menzies
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Duncan MacGregor
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
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5
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Tabak BA, Leng G, Szeto A, Parker KJ, Verbalis JG, Ziegler TE, Lee MR, Neumann ID, Mendez AJ. Advances in human oxytocin measurement: challenges and proposed solutions. Mol Psychiatry 2023; 28:127-140. [PMID: 35999276 PMCID: PMC9812775 DOI: 10.1038/s41380-022-01719-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 07/18/2022] [Accepted: 07/21/2022] [Indexed: 01/09/2023]
Abstract
Oxytocin, a neuropeptide known for its role in reproduction and socioemotional processes, may hold promise as a therapeutic agent in treating social impairments in patient populations. However, research has yet to uncover precisely how to manipulate this system for clinical benefit. Moreover, inconsistent use of standardized and validated oxytocin measurement methodologies-including the design and study of hormone secretion and biochemical assays-present unresolved challenges. Human studies measuring peripheral (i.e., in plasma, saliva, or urine) or central (i.e., in cerebrospinal fluid) oxytocin concentrations have involved very diverse methods, including the use of different assay techniques, further compounding this problem. In the present review, we describe the scientific value in measuring human endogenous oxytocin concentrations, common issues in biochemical analysis and study design that researchers face when doing so, and our recommendations for improving studies using valid and reliable methodologies.
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Affiliation(s)
- Benjamin A Tabak
- Department of Psychology, Southern Methodist University, Dallas, TX, USA.
| | - Gareth Leng
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Angela Szeto
- Department of Psychology, University of Miami, Coral Gables, FL, USA
| | - Karen J Parker
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Department of Comparative Medicine, Stanford University, Stanford, CA, USA
| | - Joseph G Verbalis
- Division of Endocrinology and Metabolism, Department of Medicine, Georgetown University Medical Center, Washington, DC, USA
| | - Toni E Ziegler
- Assay Services Unit and Institute for Clinical and Translational Research Core Laboratory, National Primate Research Center, University of Wisconsin-Madison, Madison, WI, USA
| | - Mary R Lee
- Veterans Affairs Medical Center, Washington, DC, USA
| | - Inga D Neumann
- Department of Behaviour and Molecular Neurobiology, University of Regensburg, Regensburg, Germany
| | - Armando J Mendez
- Diabetes Research Institute, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, USA
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6
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Levine AS, Jewett DC, Kotz CM, Olszewski PK. Behavioral plasticity: Role of neuropeptides in shaping feeding responses. Appetite 2022; 174:106031. [PMID: 35395362 DOI: 10.1016/j.appet.2022.106031] [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: 12/19/2021] [Revised: 03/12/2022] [Accepted: 03/29/2022] [Indexed: 11/28/2022]
Abstract
Behavioral plasticity refers to changes occurring due to external influences on an organism, including adaptation, learning, memory and enduring influences from early life experience. There are 2 types of behavioral plasticity: "developmental", which refers to gene/environment interactions affecting a phenotype, and "activational" which refers to innate physiology and can involve structural physiological changes of the body. In this review, we focus on feeding behavior, and studies involving neuropeptides that influence behavioral plasticity - primarily opioids, orexin, neuropeptide Y, and oxytocin. In each section of the review, we include examples of behavioral plasticity as it relates to actions of these neuropeptides. It can be concluded from this review that eating behavior is influenced by a number of external factors, including time of day, type of food available, energy balance state, and stressors. The reviewed work underscores that environmental factors play a critical role in feeding behavior and energy balance, but changes in eating behavior also result from a multitude of non-environmental factors, such that there can be no single mechanism or variable that can explain ingestive behavior.
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Affiliation(s)
- Allen S Levine
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN, 55113, USA.
| | - David C Jewett
- Department of Psychology, University of Wisconsin-Eau Claire, Eau Claire, WI, USA
| | - Catherine M Kotz
- Department of Integrative Biology and Physiology, Medical School, University of Minnesota, Minneapolis, MN, 55414, USA; Geriatric, Research, Education and Clinical Center, Minneapolis Veterans Affairs Health, Minneapolis, MN, 55417, USA
| | - Pawel K Olszewski
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN, 55113, USA; Department of Integrative Biology and Physiology, Medical School, University of Minnesota, Minneapolis, MN, 55414, USA; Faculty of Science and Engineering, University of Waikato, Hamilton, 3240, New Zealand
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7
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Mori H, Verbeure W, Schol J, Carbone F, Tack J. Gastrointestinal hormones and regulation of gastric emptying. Curr Opin Endocrinol Diabetes Obes 2022; 29:191-199. [PMID: 35081068 DOI: 10.1097/med.0000000000000707] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
PURPOSE OF REVIEW In this review, we evaluate recent findings related to the association between gastrointestinal hormones and regulation of gastric emptying. RECENT FINDINGS Motilin and ghrelin, which act during fasting, promote gastric motility, whereas most of the hormones secreted after a meal inhibit gastric motility. Serotonin has different progastric or antigastric motility effects depending on the receptor subtype. Serotonin receptor agonists have been used clinically to treat dyspepsia symptoms but other hormone receptor agonists or antagonists are still under development. Glucagon-like peptide 1 agonists, which have gastric motility and appetite-suppressing effects are used as a treatment for obesity and diabetes. SUMMARY Gastrointestinal hormones play an important role in the regulation of gastric motility. Various drugs have been developed to treat delayed gastric emptying by targeting gastrointestinal hormones or their receptors but few have been commercialized.
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Affiliation(s)
- Hideki Mori
- Translational Research Center for Gastrointestinal Disorders, KU Leuven, Leuven, Belgium
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8
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Niu J, Tong J, Blevins JE. Oxytocin as an Anti-obesity Treatment. Front Neurosci 2021; 15:743546. [PMID: 34720864 PMCID: PMC8549820 DOI: 10.3389/fnins.2021.743546] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 09/16/2021] [Indexed: 12/19/2022] Open
Abstract
Obesity is a growing health concern, as it increases risk for heart disease, hypertension, type 2 diabetes, cancer, COVID-19 related hospitalizations and mortality. However, current weight loss therapies are often associated with psychiatric or cardiovascular side effects or poor tolerability that limit their long-term use. The hypothalamic neuropeptide, oxytocin (OT), mediates a wide range of physiologic actions, which include reproductive behavior, formation of prosocial behaviors and control of body weight. We and others have shown that OT circumvents leptin resistance and elicits weight loss in diet-induced obese rodents and non-human primates by reducing both food intake and increasing energy expenditure (EE). Chronic intranasal OT also elicits promising effects on weight loss in obese humans. This review evaluates the potential use of OT as a therapeutic strategy to treat obesity in rodents, non-human primates, and humans, and identifies potential mechanisms that mediate this effect.
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Affiliation(s)
- JingJing Niu
- VA Puget Sound Health Care System, Office of Research and Development, Medical Research Service, Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States.,Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
| | - Jenny Tong
- VA Puget Sound Health Care System, Office of Research and Development, Medical Research Service, Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States.,Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
| | - James E Blevins
- VA Puget Sound Health Care System, Office of Research and Development, Medical Research Service, Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States.,Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
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9
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Anekonda VT, Thompson BW, Ho JM, Roberts ZS, Edwards MM, Nguyen HK, Dodson AD, Wolden-Hanson T, Chukri DW, Herbertson AJ, Graham JL, Havel PJ, Wietecha TA, O’Brien KD, Blevins JE. Hindbrain Administration of Oxytocin Reduces Food Intake, Weight Gain and Activates Catecholamine Neurons in the Hindbrain Nucleus of the Solitary Tract in Rats. J Clin Med 2021; 10:5078. [PMID: 34768597 PMCID: PMC8584350 DOI: 10.3390/jcm10215078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 11/16/2022] Open
Abstract
Existing studies show that CNS oxytocin (OT) signaling is important in the control of energy balance, but it is unclear which neurons may contribute to these effects. Our goals were to examine (1) the dose-response effects of acute OT administration into the third (3V; forebrain) and fourth (4V; hindbrain) ventricles to assess sensitivity to OT in forebrain and hindbrain sites, (2) the extent to which chronic 4V administration of OT reduces weight gain associated with the progression of diet-induced obesity, and (3) whether nucleus tractus solitarius (NTS) catecholamine neurons are downstream targets of 4V OT. Initially, we examined the dose-response effects of 3V and 4V OT (0.04, 0.2, 1, or 5 μg). 3V and 4V OT (5 μg) suppressed 0.5-h food intake by 71.7 ± 6.0% and 60 ± 12.9%, respectively. 4V OT (0.04, 0.2, 1 μg) reduced food intake by 30.9 ± 12.9, 42.1 ± 9.4, and 56.4 ± 9.0%, respectively, whereas 3V administration of OT (1 μg) was only effective at reducing 0.5-h food intake by 38.3 ± 10.9%. We subsequently found that chronic 4V OT infusion, as with chronic 3V infusion, reduced body weight gain (specific to fat mass) and tended to reduce plasma leptin in high-fat diet (HFD)-fed rats, in part, through a reduction in energy intake. Lastly, we determined that 4V OT increased the number of hindbrain caudal NTS Fos (+) neurons (156 ± 25) relative to vehicle (12 ± 3). The 4V OT also induced Fos in tyrosine hydroxylase (TH; marker of catecholamine neurons) (+) neurons (25 ± 7%) relative to vehicle (0.8 ± 0.3%). Collectively, these findings support the hypothesis that OT within the hindbrain is effective at reducing food intake, weight gain, and adiposity and that NTS catecholamine neurons in addition to non-catecholaminergic neurons are downstream targets of CNS OT.
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Affiliation(s)
- Vishwanath T. Anekonda
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Benjamin W. Thompson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Jacqueline M. Ho
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA;
| | - Zachary S. Roberts
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Melise M. Edwards
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Ha K. Nguyen
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Andrew D. Dodson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Tami Wolden-Hanson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Daniel W. Chukri
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - Adam J. Herbertson
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
| | - James L. Graham
- Department of Nutrition and Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA; (J.L.G.); (P.J.H.)
| | - Peter J. Havel
- Department of Nutrition and Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA; (J.L.G.); (P.J.H.)
| | - Tomasz A. Wietecha
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA;
- UW Medicine Diabetes Institute, University of Washington School of Medicine, Seattle, WA 98109, USA;
| | - Kevin D. O’Brien
- UW Medicine Diabetes Institute, University of Washington School of Medicine, Seattle, WA 98109, USA;
- Division of Cardiology, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - James E. Blevins
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA; (V.T.A.); (B.W.T.); (J.M.H.); (Z.S.R.); (M.M.E.); (H.K.N.); (A.D.D.); (T.W.-H.); (D.W.C.); (A.J.H.)
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA;
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10
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Guggenberger M, Engster KM, Hofmann T, Rose M, Stengel A, Kobelt P. Cholecystokinin and bombesin activate neuronatin neurons in the nucleus of the solitary tract. Brain Res 2020; 1746:147006. [DOI: 10.1016/j.brainres.2020.147006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 06/09/2020] [Accepted: 06/29/2020] [Indexed: 12/29/2022]
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11
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Yamaguchi N, Hosomi E, Hori Y, Ro S, Maezawa K, Ochiai M, Nagoshi S, Takayama K, Yakabi K. The Combination of Cholecystokinin and Stress Amplifies an Inhibition of Appetite, Gastric Emptying, and an Increase in c-Fos Expression in Neurons of the Hypothalamus and the Medulla Oblongata. Neurochem Res 2020; 45:2173-2183. [PMID: 32661781 DOI: 10.1007/s11064-020-03079-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 06/05/2020] [Accepted: 06/25/2020] [Indexed: 10/23/2022]
Abstract
Cholecystokinin (CCK) had been the first gastrointestinal hormone known to exert anorexic effects. CCK had been inferred to contribute to the onset of functional dyspepsia (FD) symptoms. To understand the pathophysiology of FD, the roles of stress have to be clarified. In this study, we aimed to clarify the influence of stress on the action of cholecystokinin (CCK) on appetite and gastric emptying. Using rats, stress was simulated by giving restraint stress or intraperitoneal injection of the stress-related peptide hormone urocortin 1 (UCN1). The effects of CCK and restraint stress, alone or in combination, on food intake and gastric motility were examined, and c-Fos expression in the neurons of appetite control network in the central nervous system was assessed by immunohistochemical staining. CCK inhibited food intake and gastric emptying in a dose-dependent manner. Food intake for 1 h was significantly lower with UCN1 (2 nmol/kg) than with the saline control. Restraint stress amplified the suppressive effects of CCK on food intake for 1 h and on gastric emptying. With regard to brain function, the CCK induced c-Fos expression in the neurons of the nucleus tractus solitarius and paraventricular nucleus of the hypothalamus was markedly and significantly amplified by the addition of restraint stress with CCK. The results suggested that stress might amplify the anorexic effects of CCK through activation of the nuclei that comprise the brain neuronal network for satiation; this might play a role in the pathogenesis of the postprandial distress syndromes of functional dyspepsia.
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Affiliation(s)
- Naomi Yamaguchi
- Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, 1981 Kamoda, Kawagoe, Saitama, Japan
| | - Eriko Hosomi
- Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, 1981 Kamoda, Kawagoe, Saitama, Japan
| | - Yutaro Hori
- Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, 1981 Kamoda, Kawagoe, Saitama, Japan
| | - Shoki Ro
- Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, 1981 Kamoda, Kawagoe, Saitama, Japan.,Central Research Laboratories, Teikyo University Chiba Medical Center, 3426-3 Anegasaki, Ichihara, Chiba, Japan
| | - Kosuke Maezawa
- Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, 1981 Kamoda, Kawagoe, Saitama, Japan
| | - Mitsuko Ochiai
- Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, 1981 Kamoda, Kawagoe, Saitama, Japan
| | - Sumiko Nagoshi
- Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, 1981 Kamoda, Kawagoe, Saitama, Japan
| | - Kiyoshige Takayama
- Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, 1981 Kamoda, Kawagoe, Saitama, Japan
| | - Koji Yakabi
- Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, 1981 Kamoda, Kawagoe, Saitama, Japan.
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12
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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: 69] [Impact Index Per Article: 17.3] [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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13
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Şahin Ç, Yıldırım N, Hortu İ, Akdemir A, Özşener S, Yiğittürk G, Erbaş O. Tadalafil attenuates ischemic damage as well as reperfusion injury in the rat ovary. J Turk Ger Gynecol Assoc 2019; 21:35-40. [PMID: 31088044 PMCID: PMC7075395 DOI: 10.4274/jtgga.galenos.2019.2018.0121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Objective: Tadalafil is a selective phosphodiesterase type-5 inhibitor with a long half-life. It has a dual function in ischaemic and re-perfused tissues, i.e. vasodilatation and anti-oxidant effects. These features of tadalafil distinguish it from other anti-oxidants. We investigated the dual effect of tadalafil on ischaemia and reperfusion injury in the rat ovary. Material and Methods: We established five study groups. Group 1 (n=6): sham-operated; group 2 (n=6): torsion; group 3 (n=6): torsion and Tadalafil; group 4 (n=6): torsion/de-torsion; and group 5 (n=6): torsion/de-torsion and tadalafil. Ovarian samples were harvested from animals and evaluated in terms of histopathologic changes, tissue malondialdehyde (MDA) concentrations, lactate production, and plasma cyclic guanosine monophosphate (cGMP). Results: Follicular degeneration, oedema, haemorrhage, and inflammatory cells were significantly decreased in group 5 in comparison with group 4. Group 2 and group 3 were compared in terms of vascular congestion and haemorrhage; these parameters were significantly decreased in group 3. In addition, significantly decreased MDA and lactate concentrations were observed in group 5 in comparison with group 4. Increased cGMP concentrations were detected in group 3 and group 5. Conclusion: We conclude that tadalafil might be useful in protecting the ovary against ischaemia and reperfusion injury. In the evet of ovarian torsion, it will provide a greater therapeutic effect than only performing de-torsion of the ovary or using other anti-oxidant agents.
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Affiliation(s)
- Çağdaş Şahin
- Department of Obstetrics and Gynecology, Ege University Faculty of Medicine, İzmir, Turkey
| | - Nuri Yıldırım
- Department of Obstetrics and Gynecology, Ege University Faculty of Medicine, İzmir, Turkey
| | - İsmet Hortu
- Department of Obstetrics and Gynecology, Ege University Faculty of Medicine, İzmir, Turkey
| | - Ali Akdemir
- Department of Obstetrics and Gynecology, Ege University Faculty of Medicine, İzmir, Turkey
| | - Serdar Özşener
- Department of Obstetrics and Gynecology, Ege University Faculty of Medicine, İzmir, Turkey
| | - Gürkan Yiğittürk
- Department of Histology and Embryology, Muğla Sıtkı Koçman University Faculty of Medicine, Muğla, Turkey
| | - Oytun Erbaş
- Department of Physiology, Demiroğlu Bilim University Faculty of Medicine, İstanbul, Turkey
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14
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Jurek B, Neumann ID. The Oxytocin Receptor: From Intracellular Signaling to Behavior. Physiol Rev 2018; 98:1805-1908. [DOI: 10.1152/physrev.00031.2017] [Citation(s) in RCA: 408] [Impact Index Per Article: 68.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The many facets of the oxytocin (OXT) system of the brain and periphery elicited nearly 25,000 publications since 1930 (see FIGURE 1 , as listed in PubMed), which revealed central roles for OXT and its receptor (OXTR) in reproduction, and social and emotional behaviors in animal and human studies focusing on mental and physical health and disease. In this review, we discuss the mechanisms of OXT expression and release, expression and binding of the OXTR in brain and periphery, OXTR-coupled signaling cascades, and their involvement in behavioral outcomes to assemble a comprehensive picture of the central and peripheral OXT system. Traditionally known for its role in milk let-down and uterine contraction during labor, OXT also has implications in physiological, and also behavioral, aspects of reproduction, such as sexual and maternal behaviors and pair bonding, but also anxiety, trust, sociability, food intake, or even drug abuse. The many facets of OXT are, on a molecular basis, brought about by a single receptor. The OXTR, a 7-transmembrane G protein-coupled receptor capable of binding to either Gαior Gαqproteins, activates a set of signaling cascades, such as the MAPK, PKC, PLC, or CaMK pathways, which converge on transcription factors like CREB or MEF-2. The cellular response to OXT includes regulation of neurite outgrowth, cellular viability, and increased survival. OXTergic projections in the brain represent anxiety and stress-regulating circuits connecting the paraventricular nucleus of the hypothalamus, amygdala, bed nucleus of the stria terminalis, or the medial prefrontal cortex. Which OXT-induced patterns finally alter the behavior of an animal or a human being is still poorly understood, and studying those OXTR-coupled signaling cascades is one initial step toward a better understanding of the molecular background of those behavioral effects.
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Affiliation(s)
- Benjamin Jurek
- Department of Behavioural and Molecular Neurobiology, Institute of Zoology, University of Regensburg, Regensburg, Germany
| | - Inga D. Neumann
- Department of Behavioural and Molecular Neurobiology, Institute of Zoology, University of Regensburg, Regensburg, Germany
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15
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Bassi GS, Dias DPM, Franchin M, Talbot J, Reis DG, Menezes GB, Castania JA, Garcia-Cairasco N, Resstel LBM, Salgado HC, Cunha FQ, Cunha TM, Ulloa L, Kanashiro A. Modulation of experimental arthritis by vagal sensory and central brain stimulation. Brain Behav Immun 2017; 64:330-343. [PMID: 28392428 PMCID: PMC6330674 DOI: 10.1016/j.bbi.2017.04.003] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 02/25/2017] [Accepted: 04/04/2017] [Indexed: 12/20/2022] Open
Abstract
Articular inflammation is a major clinical burden in multiple inflammatory diseases, especially in rheumatoid arthritis. Biological anti-rheumatic drug therapies are expensive and increase the risk of systemic immunosuppression, infections, and malignancies. Here, we report that vagus nerve stimulation controls arthritic joint inflammation by inducing local regulation of innate immune response. Most of the previous studies of neuromodulation focused on vagal regulation of inflammation via the efferent peripheral pathway toward the viscera. Here, we report that vagal stimulation modulates arthritic joint inflammation through a novel "afferent" pathway mediated by the locus coeruleus (LC) of the central nervous system. Afferent vagal stimulation activates two sympatho-excitatory brain areas: the paraventricular hypothalamic nucleus (PVN) and the LC. The integrity of the LC, but not that of the PVN, is critical for vagal control of arthritic joint inflammation. Afferent vagal stimulation suppresses articular inflammation in the ipsilateral, but not in the contralateral knee to the hemispheric LC lesion. Central stimulation is followed by subsequent activation of joint sympathetic nerve terminals inducing articular norepinephrine release. Selective adrenergic beta-blockers prevent the effects of articular norepinephrine and thereby abrogate vagal control of arthritic joint inflammation. These results reveals a novel neuro-immune brain map with afferent vagal signals controlling side-specific articular inflammation through specific inflammatory-processing brain centers and joint sympathetic innervations.
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Affiliation(s)
- Gabriel Shimizu Bassi
- Department of Immunology, Ribeirão Preto Medical School - University of São Paulo, Ribeirão Preto, SP, Brazil.
| | | | - Marcelo Franchin
- Department of Pharmacology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Jhimmy Talbot
- Department of Pharmacology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Daniel Gustavo Reis
- Department of Pharmacology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Gustavo Batista Menezes
- Center for Gastrointestinal Biology, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Jaci Airton Castania
- Department of Physiology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Norberto Garcia-Cairasco
- Department of Physiology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Helio Cesar Salgado
- Department of Physiology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Fernando Queiró Cunha
- Department of Pharmacology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Thiago Mattar Cunha
- Department of Pharmacology, Ribeirão Preto Medical School – University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Luis Ulloa
- Department of Surgery, Center of Immunology & Inflammation, Rutgers-New Jersey Medical School, Rutgers University, Newark, NJ 07101, USA.
| | - Alexandre Kanashiro
- Department of Pharmacology, Ribeirão Preto Medical School - University of São Paulo, Ribeirão Preto, SP, Brazil; Department of Physiological Sciences, Federal University of São Carlos, São Carlos, SP, Brazil.
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16
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Samson WK. Oxytocin redux. Am J Physiol Regul Integr Comp Physiol 2016; 311:R710-R713. [PMID: 27511282 DOI: 10.1152/ajpregu.00307.2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 08/08/2016] [Accepted: 08/09/2016] [Indexed: 11/22/2022]
Affiliation(s)
- Willis K Samson
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, Missouri
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17
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Motojima Y, Kawasaki M, Matsuura T, Saito R, Yoshimura M, Hashimoto H, Ueno H, Maruyama T, Suzuki H, Ohnishi H, Sakai A, Ueta Y. Effects of peripherally administered cholecystokinin-8 and secretin on feeding/drinking and oxytocin-mRFP1 fluorescence in transgenic rats. Neurosci Res 2016; 109:63-9. [PMID: 26919961 DOI: 10.1016/j.neures.2016.02.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 02/17/2016] [Accepted: 02/18/2016] [Indexed: 12/27/2022]
Abstract
Peripheral administration of cholecystokinin (CCK)-8 or secretin activates oxytocin (OXT)-secreting neurons in the hypothalamus. Although OXT is involved in the regulation of feeding behavior, detailed mechanism remains unclear. In the present study, we examined the central OXTergic pathways after intraperitoneally (i.p.) administration of CCK-8 and secretin using male OXT-monomeric red fluorescent protein 1 (mRFP1) transgenic rats and male Wistar rats. I.p. administration of CCK-8 (50μg/kg) and secretin (100μg/kg) decreased food intake in these rats. While i.p. administration of CCK-8 decreased water intake, i.p. administration of secretin increased water intake. Immunohistochemical study revealed that Fos-Like-Immunoreactive cells were observed abundantly in the brainstem and in the OXT neurons in the dorsal division of the parvocellular paraventricular nucleus (dpPVN). We could observe marked increase of mRFP1 fluorescence, as an indicator for OXT, in the dpPVN and mRFP1-positive granules in axon terminals of the dpPVN OXT neurons in the nucleus tractus solitarius (NTS) after i.p. administration of CCK-8 and secretin. These results provide us the evidence that, at least in part, i.p. administration of CCK-8 or secretin might be involved in the regulation of feeding/drinking via a OXTergic pathway from the dpPVN to the NTS.
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Affiliation(s)
- Yasuhito Motojima
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan; Department of Orthopaedics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Makoto Kawasaki
- Department of Orthopaedics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Takanori Matsuura
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan; Department of Orthopaedics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Reiko Saito
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Mitsuhiro Yoshimura
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Hirofumi Hashimoto
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Hiromichi Ueno
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Takashi Maruyama
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Hitoshi Suzuki
- Department of Orthopaedics, Wakamatsu Hospital for University of Occupational and Environmental Health, Kitakyushu 808-0024, Japan
| | - Hideo Ohnishi
- Department of Orthopaedics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Akinori Sakai
- Department of Orthopaedics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan
| | - Yoichi Ueta
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan.
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18
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Olszewski PK, Klockars A, Levine AS. Oxytocin: A Conditional Anorexigen whose Effects on Appetite Depend on the Physiological, Behavioural and Social Contexts. J Neuroendocrinol 2016; 28. [PMID: 26918919 DOI: 10.1111/jne.12376] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 02/16/2016] [Accepted: 02/19/2016] [Indexed: 01/17/2023]
Abstract
Central oxytocin suppresses appetite. Neuronal activity and the release of oxytocin coincide with satiation, as well as with adverse events (e.g. hyperosmolality, toxicity or excessive stomach distension) that necessitate an immediate termination of eating behaviour. Oxytocin also decreases consumption driven by reward, especially as derived from ingesting carbohydrates and sweet tastants. This review summarises current knowledge of the role of oxytocin in food intake regulation and highlights a growing body of evidence showing that oxytocin is a conditional anorexigen [i.e. its effects on appetite differ significantly with respect to certain (patho)physiological, behavioural and social contexts].
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Affiliation(s)
- P K Olszewski
- Department of Biological Sciences, University of Waikato, Hamilton, New Zealand
| | - A Klockars
- Department of Biological Sciences, University of Waikato, Hamilton, New Zealand
| | - A S Levine
- Department of Food Science and Nutrition, University of Minnesota, St Paul, MN, USA
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19
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Romano A, Tempesta B, Micioni Di Bonaventura MV, Gaetani S. From Autism to Eating Disorders and More: The Role of Oxytocin in Neuropsychiatric Disorders. Front Neurosci 2016; 9:497. [PMID: 26793046 PMCID: PMC4709851 DOI: 10.3389/fnins.2015.00497] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 12/14/2015] [Indexed: 11/13/2022] Open
Abstract
Oxytocin (oxy) is a pituitary neuropeptide hormone synthesized from the paraventricular and supraoptic nuclei within the hypothalamus. Like other neuropeptides, oxy can modulate a wide range of neurotransmitter and neuromodulator activities. Additionally, through the neurohypophysis, oxy is secreted into the systemic circulation to act as a hormone, thereby influencing several body functions. Oxy plays a pivotal role in parturition, milk let-down and maternal behavior and has been demonstrated to be important in the formation of pair bonding between mother and infants as well as in mating pairs. Furthermore, oxy has been proven to play a key role in the regulation of several behaviors associated with neuropsychiatric disorders, including social interactions, social memory response to social stimuli, decision-making in the context of social interactions, feeding behavior, emotional reactivity, etc. An increasing body of evidence suggests that deregulations of the oxytocinergic system might be involved in the pathophysiology of certain neuropsychiatric disorders such as autism, eating disorders, schizophrenia, mood, and anxiety disorders. The potential use of oxy in these mental health disorders is attracting growing interest since numerous beneficial properties are ascribed to this neuropeptide. The present manuscript will review the existing findings on the role played by oxy in a variety of distinct physiological and behavioral functions (Figure 1) and on its role and impact in different psychiatric disorders. The aim of this review is to highlight the need of further investigations on this target that might contribute to the development of novel more efficacious therapies.
Oxytocin regulatory control of different and complex processes. ![]()
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Affiliation(s)
- Adele Romano
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome Rome, Italy
| | - Bianca Tempesta
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome Rome, Italy
| | | | - Silvana Gaetani
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome Rome, Italy
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20
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Ong ZY, Alhadeff AL, Grill HJ. Medial nucleus tractus solitarius oxytocin receptor signaling and food intake control: the role of gastrointestinal satiation signal processing. Am J Physiol Regul Integr Comp Physiol 2015; 308:R800-6. [PMID: 25740340 DOI: 10.1152/ajpregu.00534.2014] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 02/24/2015] [Indexed: 12/23/2022]
Abstract
Central oxytocin (OT) administration reduces food intake and its effects are mediated, in part, by hindbrain oxytocin receptor (OT-R) signaling. The neural substrate and mechanisms mediating the intake inhibitory effects of hindbrain OT-R signaling are undefined. We examined the hypothesis that hindbrain OT-R-mediated feeding inhibition results from an interaction between medial nucleus tractus solitarius (mNTS) OT-R signaling and the processing of gastrointestinal (GI) satiation signals by neurons of the mNTS. Here, we demonstrated that mNTS or fourth ventricle (4V) microinjections of OT in rats reduced chow intake in a dose-dependent manner. To examine whether the intake suppressive effects of mNTS OT-R signaling is mediated by GI signal processing, rats were injected with OT to the 4V (1 μg) or mNTS (0.3 μg), followed by self-ingestion of a nutrient preload, where either treatment was designed to be without effect on chow intake. Results showed that the combination of mNTS OT-R signaling and GI signaling processing by preload ingestion reduced chow intake significantly and to a greater extent than either stimulus alone. Using enzyme immunoassay, endogenous OT content in mNTS-enriched dorsal vagal complex (DVC) in response to ingestion of nutrient preload was measured. Results revealed that preload ingestion significantly elevated endogenous DVC OT content. Taken together, these findings provide evidence that mNTS neurons are a site of action for hindbrain OT-R signaling in food intake control and that the intake inhibitory effects of hindbrain mNTS OT-R signaling are mediated by interactions with GI satiation signal processing by mNTS neurons.
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Affiliation(s)
- Zhi Yi Ong
- Department of Psychology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Amber L Alhadeff
- Department of Psychology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Harvey J Grill
- Department of Psychology, University of Pennsylvania, Philadelphia, Pennsylvania
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21
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Iwasaki Y, Maejima Y, Suyama S, Yoshida M, Arai T, Katsurada K, Kumari P, Nakabayashi H, Kakei M, Yada T. Peripheral oxytocin activates vagal afferent neurons to suppress feeding in normal and leptin-resistant mice: a route for ameliorating hyperphagia and obesity. Am J Physiol Regul Integr Comp Physiol 2015; 308:R360-9. [DOI: 10.1152/ajpregu.00344.2014] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Oxytocin (Oxt), a neuropeptide produced in the hypothalamus, is implicated in regulation of feeding. Recent studies have shown that peripheral administration of Oxt suppresses feeding and, when infused subchronically, ameliorates hyperphagic obesity. However, the route through which peripheral Oxt informs the brain is obscure. This study aimed to explore whether vagal afferents mediate the sensing and anorexigenic effect of peripherally injected Oxt in mice. Intraperitoneal Oxt injection suppressed food intake and increased c-Fos expression in nucleus tractus solitarius to which vagal afferents project. The Oxt-induced feeding suppression and c-Fos expression in nucleus tractus solitarius were blunted in mice whose vagal afferent nerves were blocked by subdiaphragmatic vagotomy or capsaicin treatment. Oxt induced membrane depolarization and increases in cytosolic Ca2+ concentration ([Ca2+]i) in single vagal afferent neurons. The Oxt-induced [Ca2+]i increases were markedly suppressed by Oxt receptor antagonist. These Oxt-responsive neurons also responded to cholecystokinin-8 and contained cocaine- and amphetamine-regulated transcript. In obese diabetic db/db mice, leptin failed to increase, but Oxt increased [Ca2+]i in vagal afferent neurons, and single or subchronic infusion of Oxt decreased food intake and body weight gain. These results demonstrate that peripheral Oxt injection suppresses food intake by activating vagal afferent neurons and thereby ameliorates obesity in leptin-resistant db/db mice. The peripheral Oxt-regulated vagal afferent neuron provides a novel target for treating hyperphagia and obesity.
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Affiliation(s)
- Yusaku Iwasaki
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Yuko Maejima
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Shigetomo Suyama
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Masashi Yoshida
- First Department of Medicine, Saitama Medical Center, Jichi Medical University School of Medicine, Saitama, Japan
| | - Takeshi Arai
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Kenichi Katsurada
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Parmila Kumari
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Hajime Nakabayashi
- Health Science Service Center, Kanazawa University, Ishikawa, Japan; and
| | - Masafumi Kakei
- First Department of Medicine, Saitama Medical Center, Jichi Medical University School of Medicine, Saitama, Japan
| | - Toshihiko Yada
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, Tochigi, Japan
- Division of Adaptation Development, Department of Developmental Physiology, National Institute for Physiological Sciences, Aichi, Japan
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22
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Akdemir A, Sahin C, Erbas O, Yeniel AO, Sendag F. Is ursodeoxycholic acid crucial for ischemia/reperfusion-induced ovarian injury in rat ovary? Arch Gynecol Obstet 2015; 292:445-50. [DOI: 10.1007/s00404-015-3646-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 01/30/2015] [Indexed: 12/20/2022]
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23
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Engster KM, Frommelt L, Hofmann T, Nolte S, Fischer F, Rose M, Stengel A, Kobelt P. Peripheral injected cholecystokinin-8S modulates the concentration of serotonin in nerve fibers of the rat brainstem. Peptides 2014; 59:25-33. [PMID: 25017242 DOI: 10.1016/j.peptides.2014.07.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 07/02/2014] [Accepted: 07/02/2014] [Indexed: 02/05/2023]
Abstract
Serotonin and cholecystokinin (CCK) play a role in the short-term inhibition of food intake. It is known that peripheral injection of CCK increases c-Fos-immunoreactivity (Fos-IR) in the nucleus of the solitary tract (NTS) in rats, and injection of the serotonin antagonist ondansetron decreases the number of c-Fos-IR cells in the NTS. This supports the idea of serotonin contributing to the effects of CCK. The aim of the present study was to elucidate whether peripherally injected CCK-8S modulates the concentration of serotonin in brain feeding-regulatory nuclei. Ad libitum fed male Sprague-Dawley rats received 5.2 and 8.7 nmol/kg CCK-8S (n=3/group) or 0.15M NaCl (n=3-5/group) injected intraperitoneally (ip). The number of c-Fos-IR neurons, and the fluorescence intensity of serotonin in nerve fibers were assessed in the paraventricular nucleus (PVN), arcuate nucleus (ARC), NTS and dorsal motor nucleus of the vagus (DMV). CCK-8S increased the number of c-Fos-ir neurons in the NTS (mean±SEM: 72±4, and 112±5 neurons/section, respectively) compared to vehicle-treated rats (7±2 neurons/section, P<0.05), but did not modulate c-Fos expression in the DMV or ARC. Additionally, CCK-8S dose-dependently increased the number of c-Fos-positive neurons in the PVN (218±15 and 128±14, respectively vs. 19±5, P<0.05). In the NTS and DMV we observed a decrease of serotonin-immunoreactivity 90 min after injection of CCK-8S (46±2 and 49±8 pixel/section, respectively) compared to vehicle (81±8 pixel/section, P<0.05). No changes of serotonin-immunoreactivity were observed in the PVN and ARC. Our results suggest that serotonin is involved in the mediation of CCK-8's effects in the brainstem.
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Affiliation(s)
- Kim-Marie Engster
- Medical Clinic, Department of Psychosomatic Medicine, Charité - Universitätsmedizin Berlin, Germany
| | - Lisa Frommelt
- Medical Clinic, Department of Psychosomatic Medicine, Charité - Universitätsmedizin Berlin, Germany
| | - Tobias Hofmann
- Medical Clinic, Department of Psychosomatic Medicine, Charité - Universitätsmedizin Berlin, Germany
| | - Sandra Nolte
- Medical Clinic, Department of Psychosomatic Medicine, Charité - Universitätsmedizin Berlin, Germany
| | - Felix Fischer
- Medical Clinic, Department of Psychosomatic Medicine, Charité - Universitätsmedizin Berlin, Germany
| | - Matthias Rose
- Medical Clinic, Department of Psychosomatic Medicine, Charité - Universitätsmedizin Berlin, Germany
| | - Andreas Stengel
- Medical Clinic, Department of Psychosomatic Medicine, Charité - Universitätsmedizin Berlin, Germany
| | - Peter Kobelt
- Medical Clinic, Department of Psychosomatic Medicine, Charité - Universitätsmedizin Berlin, Germany.
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24
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Ho JM, Anekonda VT, Thompson BW, Zhu M, Curry RW, Hwang BH, Morton GJ, Schwartz MW, Baskin DG, Appleyard SM, Blevins JE. Hindbrain oxytocin receptors contribute to the effects of circulating oxytocin on food intake in male rats. Endocrinology 2014; 155:2845-57. [PMID: 24877632 PMCID: PMC4098005 DOI: 10.1210/en.2014-1148] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Oxytocin (OT)-elicited hypophagia has been linked to neural activity in the nucleus of the solitary tract (NTS). Because plasma OT levels increase after a meal, we hypothesized that circulating OT acts at both peripheral and hindbrain OT receptors (OTRs) to limit food intake. To initially determine whether circulating OT inhibits food intake by acting at hindbrain OTRs, we pretreated rats with an OTR antagonist administered into the fourth ventricle (4V) followed by either central or systemic OT administration. Administration of the OTR antagonist into the 4V blocked anorexia induced by either 4V or i.p. injection of OT. However, blockade of peripheral OTRs also weakened the anorectic response to ip OT. Our data suggest a predominant role for hindbrain OTRs in the hypophagic response to peripheral OT administration. To elucidate central mechanisms of OT hypophagia, we tested whether OT activates NTS catecholaminergic neurons. OT (ip) increased the number of NTS cells expressing c-Fos, of which 10%-15% were catecholaminergic. Furthermore, electrophysiological studies in mice revealed that OT stimulated 47% (8 of 17) of NTS catecholamine neurons through a presynaptic mechanism. However, OT-elicited hypophagia did not appear to require activation of α1-adrenoceptors, and blockade of glucagon-like peptide-1 receptors similarly did not attenuate anorexia induced by OT. These findings demonstrate that OT elicits satiety through both central and peripheral OTRs and that although catecholamine neurons are a downstream target of OT signaling in the NTS, the hypophagic effect is mediated independently of α1-adrenoceptor signaling.
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Affiliation(s)
- Jacqueline M Ho
- Research and Development Service (J.M.H., V.T.A., B.W.T., R.W.C., B.H.H., D.G.B., J.E.B.), Veterans Affairs Puget Sound Health Care System, Seattle, Washington 98108; Department of Medicine (J.M.H., G.J.M., M.W.S., D.G.B., J.E.B.), Division of Metabolism, Endocrinology, and Nutrition, and Diabetes and Obesity Center of Excellence (G.J.M., M.W.S.), Department of Medicine, University of Washington, Seattle, Washington 98195; Program in Neuroscience (M.Z., S.M.A.), Department of Integrative Physiology and Neuroscience, Washington State University, Pullman, Washington 99164
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25
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Lo CC, Davidson WS, Hibbard SK, Georgievsky M, Lee A, Tso P, Woods SC. Intraperitoneal CCK and fourth-intraventricular Apo AIV require both peripheral and NTS CCK1R to reduce food intake in male rats. Endocrinology 2014; 155:1700-7. [PMID: 24564397 PMCID: PMC3990852 DOI: 10.1210/en.2013-1846] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Apolipoprotein AIV (Apo AIV) and cholecystokinin (CCK) are secreted in response to fat consumption, and both cause satiation via CCK 1 receptor (CCK-1R)-containing vagal afferent nerves to the nucleus of the solitary tract (NTS), where Apo AIV is also synthesized. Fasted male Long-Evans rats received ip CCK-8 or fourth-ventricular (i4vt) Apo AIV alone or in combination. Food intake and c-Fos proteins (a product of the c-Fos immediate-early gene) were assessed. i4vt Apo AIV and/or ip CCK at effective doses reduced food intake and activated c-Fos proteins in the NTS and hypothalamic arcuate nucleus and paraventricular nucleus. Blockade of the CCK-1R by i4vt lorglumide adjacent to the NTS attenuated the satiating and c-Fos-stimulating effects of CCK and Apo AIV, alone or in combination. Maintenance on a high-fat diet (HFD) for 10 weeks resulted in weight gain and attenuation of both the behavioral and c-Fos responses to a greater extent than occurred in low-fat diet-fed and pair-fed HFD animals. These observations suggest that NTS Apo AIV or/and peripheral CCK requires vagal CCK-1R signaling to elicit satiation and that maintenance on a HFD reduces the satiating capacity of these 2 signals.
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MESH Headings
- Animals
- Apolipoproteins A/administration & dosage
- Apolipoproteins A/genetics
- Apolipoproteins A/metabolism
- Apolipoproteins A/pharmacology
- Appetite Depressants/administration & dosage
- Appetite Depressants/pharmacology
- Appetite Depressants/therapeutic use
- Appetite Regulation/drug effects
- Appetite Stimulants/administration & dosage
- Appetite Stimulants/pharmacology
- Appetitive Behavior/drug effects
- Behavior, Animal/drug effects
- Cholecystokinin/administration & dosage
- Cholecystokinin/analogs & derivatives
- Cholecystokinin/antagonists & inhibitors
- Cholecystokinin/metabolism
- Diet, High-Fat/adverse effects
- Hormone Antagonists/administration & dosage
- Hormone Antagonists/pharmacology
- Infusions, Intraventricular
- Injections, Intraperitoneal
- Male
- Nerve Tissue Proteins/administration & dosage
- Nerve Tissue Proteins/agonists
- Nerve Tissue Proteins/antagonists & inhibitors
- Nerve Tissue Proteins/metabolism
- Neurons, Afferent/drug effects
- Neurons, Afferent/metabolism
- Obesity/drug therapy
- Obesity/etiology
- Obesity/metabolism
- Rats
- Rats, Long-Evans
- Receptor, Cholecystokinin A/agonists
- Receptor, Cholecystokinin A/antagonists & inhibitors
- Receptor, Cholecystokinin A/metabolism
- Recombinant Proteins/administration & dosage
- Recombinant Proteins/pharmacology
- Sincalide/administration & dosage
- Sincalide/analogs & derivatives
- Sincalide/pharmacology
- Solitary Nucleus/drug effects
- Solitary Nucleus/metabolism
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Affiliation(s)
- Chunmin C Lo
- Departments of Pathology and Laboratory Medicine (C.C.L., W.S.D., S.K.H., M.G., A.L., P.T.) and Psychiatry and Behavioral Neuroscience (S.C.W.), Metabolic Diseases Institute, University of Cincinnati, Cincinnati, Ohio 45237-0507
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26
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Akdemir A, Erbas O, Gode F, Ergenoglu M, Yeniel O, Oltulu F, Yavasoglu A, Taskiran D. Protective effect of oxytocin on ovarian ischemia-reperfusion injury in rats. Peptides 2014; 55:126-30. [PMID: 24630974 DOI: 10.1016/j.peptides.2014.02.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Revised: 02/24/2014] [Accepted: 02/25/2014] [Indexed: 01/14/2023]
Abstract
Oxytocin (OT), a neurohypophysial nonapeptide, plays dual role as a neurotransmitter/neuromodulator and a hormone. It has also well known protective properties against ischemia/reperfusion organ damage. This study investigated the effect of OT on experimentally induced ovarian torsion/de-torsion ischemia/reperfusion (I/R) injury in rats. Sprague-Dawley rats were assigned to five treatment groups (n=7/group): Group 1, sham-operated; Group 2, torsion; Group 3, 80 IU/kg of OT administration 30 min prior to torsion; Group 4, torsion/de-torsion; and Group 5, torsion followed by 80 IU/kg of OT administration 30 min prior to de-torsion. OT administration significantly decreased the tissue malondialdehyde (MDA) levels in both the torsion and OT group (Group 3), and torsion/de-torsion OT group (Group 5) in comparison with the torsion-only group (Group 2) and torsion/de-torsion group (Group 4). Histopathological finding scores including follicular degeneration, edema, hemorrhage, vascular congestion, and infiltration by inflammatory cells were found to be significantly decreased in the torsion and OT group (Group 3), and torsion/de-torsion OT group (Group 5) when compared with the torsion-only group (Group 2) and torsion/de-torsion group (Group 4). In conclusion, these results, verified with histopathologic evaluation and biochemical assays, suggest a probable protective role for OT in ischemia and I/R injury in rat ovaries.
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Affiliation(s)
- Ali Akdemir
- Department of Obstetrics and Gynecology, Ege University School of Medicine, Izmir, Turkey
| | - Oytun Erbas
- Department of Physiology, Ege University School of Medicine, Izmir, Turkey
| | - Funda Gode
- Department of Obstetrics and Gynecology, Kent Hospital, Izmir, Turkey.
| | - Mete Ergenoglu
- Department of Obstetrics and Gynecology, Ege University School of Medicine, Izmir, Turkey
| | - Ozgur Yeniel
- Department of Obstetrics and Gynecology, Ege University School of Medicine, Izmir, Turkey
| | - Fatih Oltulu
- Department of Histology and Embryology, Ege University School of Medicine, Izmir, Turkey
| | - Altug Yavasoglu
- Department of Histology and Embryology, Ege University School of Medicine, Izmir, Turkey
| | - Dilek Taskiran
- Department of Physiology, Ege University School of Medicine, Izmir, Turkey
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27
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Luo J, Wang T, Liang S, Hu X, Li W, Jin F. Experimental gastritis leads to anxiety- and depression-like behaviors in female but not male rats. BEHAVIORAL AND BRAIN FUNCTIONS : BBF 2013; 9:46. [PMID: 24345032 PMCID: PMC3878489 DOI: 10.1186/1744-9081-9-46] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 12/10/2013] [Indexed: 02/08/2023]
Abstract
Human and animals studies support the idea that there is a gender-related co-morbidity of pain-related and inflammatory gastrointestinal (GI) diseases with psychological disorders. This co-morbidity is the evidence for the existence of GI-brain axis which consists of immune (cytokines), neural (vagus nerve) and neuroendocrine (HPA axis) pathways. Psychological stress causes disturbances in GI physiology, such as altered GI barrier function, changes in motility and secretion, development of visceral hypersensitivity, and dysfunction of inflammatory responses. Whether GI inflammation would exert impact on psychological behavior is not well established. We examined the effect of experimental gastritis on anxiety- and depression-like behaviors in male and female Sprague-Dawley rats, and evaluated potential mechanisms of action. Gastritis was induced by adding 0.1% (w/v) iodoacetamide (IAA) to the sterile drinking water for 7 days. Sucrose preference test assessed the depression-like behavior, open field test and elevated plus maze evaluated the anxiety-like behavior. IAA treatment induced gastric inflammation in rats of either gender. No behavioral abnormality or dysfunction of GI-brain axis was observed in male rats with IAA-induced gastritis. Anxiety- and depression-like behaviors were apparent and the HPA axis was hyperactive in female rats with IAA-induced gastritis. Our results show that gastric inflammation leads to anxiety- and depression-like behaviors in female but not male rats via the neuroendocrine (HPA axis) pathway, suggesting that the GI inflammation can impair normal brain function and induce changes in psychological behavior in a gender-related manner through the GI-to-brain signaling.
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Affiliation(s)
- Jia Luo
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Tao Wang
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
| | - Shan Liang
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xu Hu
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
| | - Wei Li
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Feng Jin
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
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28
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Abstract
Obesity and its associated metabolic disorders are growing health concerns in the US and worldwide. In the US alone, more than two-thirds of the adult population is classified as either overweight or obese [1], highlighting the need to develop new, effective treatments for these conditions. Whereas the hormone oxytocin is well known for its peripheral effects on uterine contraction during parturition and milk ejection during lactation, release of oxytocin from somatodendrites and axonal terminals within the central nervous system (CNS) is implicated in both the formation of prosocial behaviors and in the control of energy balance. Recent findings demonstrate that chronic administration of oxytocin reduces food intake and body weight in diet-induced obese (DIO) and genetically obese rodents with impaired or defective leptin signaling. Importantly, chronic systemic administration of oxytocin out to 6 weeks recapitulates the effects of central administration on body weight loss in DIO rodents at doses that do not result in the development of tolerance. Furthermore, these effects are coupled with induction of Fos (a marker of neuronal activation) in hindbrain areas (e.g. dorsal vagal complex (DVC)) linked to the control of meal size and forebrain areas (e.g. hypothalamus, amygdala) linked to the regulation of food intake and body weight. This review assesses the potential central and peripheral targets by which oxytocin may inhibit body weight gain, its regulation by anorexigenic and orexigenic signals, and its potential use as a therapy that can circumvent leptin resistance and reverse the behavioral and metabolic abnormalities associated with DIO and genetically obese models.
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Affiliation(s)
- James E Blevins
- VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA, 98108, USA,
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29
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Elberry AA, Refaie SM, Kamel M, Ali T, Darwish H, Ashour O. Oxytocin ameliorates cisplatin-induced nephrotoxicity in Wistar rats. Ann Saudi Med 2013; 33:57-62. [PMID: 23458943 PMCID: PMC6078576 DOI: 10.5144/0256-4947.2013.57] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND AND OBJECTIVES The clinical use of cisplatin (CP) is highly limited because of its renal toxicity and the production of reactive oxygen species (ROS) that intensify the cytotoxic effects. Oxytocin (OT) was previously shown to have antioxidant activity. DESIGN AND SETTING Experimental study on male Wistar albino rats performed in the Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia. METHODS Forty-eight male Wistar albino rats were classified into four equal groups: a control group, OT only-treated group which received OT twice (500 micro g/kg intraperitoneally (ip) 30 minutes and just before saline administration), a CP-induced nephrotoxicity group that received a single dose of CP (7.5 mg/kg ip) and treated with saline, and CP+OT group treated with the same previous doses. Seventy-two hours after CP administration, the rats were sacrificed and blood was withdrawn for determination of urea, creatinine, albumin and lactate dehydrogenase (LDH). The kidneys were extracted for histopathological examination and determination of the tissue levels of reduced glutathione (GSH), thiobarbituric acid reactive substances (TBARS) and nitric oxide end product nitrite (NO(2)). Glutathione S-transferase (GST), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and myeloperoxidase (MPO) activities were assessed. RESULTS CP-induced renal injury was evidenced histopathologically and manifested by a significant increase in serum LDH activity as well as urea and creatinine levels. Moreover, renal injury was associated with decreased renal tissue activities of CAT, SOD, GPx and GST as well as GSH level. On the other hand, renal tissue content of TBARS and NO(2) as well as the activity of MPO were increased. Alterations in these biochemical and histopathological indices due to CP were attenuated by OT. CONCLUSION OT protected rats from CP-induced nephrotoxicity. Such protection is attributed, at least in part, to its antioxidant activity.
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Affiliation(s)
- Ahmed A Elberry
- Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia.
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30
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Abstract
During pregnancy, food intake and fat mass are increased to meet the energy demands of the growing conceptus and to prepare for the subsequent demands of lactation. A state of leptin resistance develops during pregnancy in the rat, which can facilitate the increase in food intake despite pregnancy-induced increases in leptin concentrations. Cholecystokinin (CCK) is a satiety factor that is released from the gut during feeding and acts to terminate short-term food intake. Circulating leptin concentrations can modulate the anorexic response to CCK; low leptin concentrations decrease the potency of CCK to reduce food intake. Because rats are leptin resistant by day 14 of pregnancy, it was hypothesised that the feeding response to CCK would be attenuated at that time. Nonpregnant and day 14 pregnant rats received an i.p. injection of CCK-8 (3 μg/kg body weight) or vehicle directly before the start of the dark phase. Food intake was measured 30 min after lights out. Approximately 90 min after receiving either CCK-8 or vehicle, rats were transcardially perfused with 4% paraformaldehyde. Food intake was significantly decreased in CCK-treated nonpregnant rats, although similar treatment did not reduce food intake in day 14 pregnant rats. CCK treatment lead to significant increased in c-Fos expression in the nucleus of the solitary tract (NTS) in both nonpregnant and pregnant rats compared to vehicle treatment, although the number of CCK-induced c-Fos positive cells was significantly less in pregnant rat compared to nonpregnant rats. Although CCK treatment increased the number of c-Fos positive cells in the hypothalamic paraventricular nucleus and supraoptic nucleus in nonpregnant rats, no significant increase was observed in these areas during pregnancy. These results indicate that pregnant rats are no longer responsive to the actions of CCK on short-term food intake and that CCK action in the NTS is reduced during pregnancy.
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Affiliation(s)
- S R Ladyman
- Centre for Neuroendocrinology and Department of Anatomy, University of Otago, Dunedin, New Zealand.
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31
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Oxytocin inhibits NADPH oxidase and P38 MAPK in cisplatin-induced nephrotoxicity. Biomed Pharmacother 2011; 65:474-80. [DOI: 10.1016/j.biopha.2011.07.001] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Accepted: 07/11/2011] [Indexed: 12/11/2022] Open
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32
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Lembke V, Goebel M, Frommelt L, Inhoff T, Lommel R, Stengel A, Taché Y, Grötzinger C, Bannert N, Wiedenmann B, Klapp BF, Kobelt P. Sulfated cholecystokinin-8 activates phospho-mTOR immunoreactive neurons of the paraventricular nucleus in rats. Peptides 2011; 32:65-70. [PMID: 20933028 PMCID: PMC4040259 DOI: 10.1016/j.peptides.2010.09.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Revised: 09/28/2010] [Accepted: 09/28/2010] [Indexed: 12/13/2022]
Abstract
The serin/threonin-kinase, mammalian target of rapamycin (mTOR) was detected in the arcuate nucleus (ARC) and paraventricular nucleus of the hypothalamus (PVN) and suggested to play a role in the integration of satiety signals. Since cholecystokinin (CCK) plays a role in the short-term inhibition of food intake and induces c-Fos in PVN neurons, the aim was to determine whether intraperitoneally injected CCK-8S affects the neuronal activity in cells immunoreactive for phospho-mTOR in the PVN. Ad libitum fed male Sprague-Dawley rats received 6 or 10 μg/kg CCK-8S or 0.15M NaCl ip (n=4/group). The number of c-Fos-immunoreactive (ir) neurons was assessed in the PVN, ARC and in the nucleus of the solitary tract (NTS). CCK-8S increased the number of c-Fos-ir neurons in the PVN (6 μg: 103 ± 13 vs. 10 μg: 165 ± 14 neurons/section; p<0.05) compared to vehicle treated rats (4 ± 1, p<0.05), but not in the ARC. CCK-8S also dose-dependently increased the number of c-Fos neurons in the NTS. Staining for phospho-mTOR and c-Fos in the PVN showed a dose-dependent increase of activated phospho-mTOR neurons (17 ± 3 vs. 38 ± 2 neurons/section; p<0.05), while no activated phospho-mTOR neurons were observed in the vehicle group. Triple staining in the PVN showed activation of phospho-mTOR neurons co-localized with oxytocin, corresponding to 9.8 ± 3.6% and 19.5 ± 3.3% of oxytocin neurons respectively. Our observations indicate that peripheral CCK-8S activates phospho-mTOR neurons in the PVN and suggest that phospho-mTOR plays a role in the mediation of CCK-8S's anorexigenic effects.
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Affiliation(s)
- Vanessa Lembke
- Department of Medicine, Division Psychosomatic Medicine and Psychotherapy; Charité, Campus Mitte; Universitätsmedizin Berlin, Germany
| | - Miriam Goebel
- Department of Medicine, Division of Digestive Diseases, CURE Digestive Diseases Research Center and Center for Neurobiology of Stress, UCLA and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Lisa Frommelt
- Department of Medicine, Division Psychosomatic Medicine and Psychotherapy; Charité, Campus Mitte; Universitätsmedizin Berlin, Germany
| | - Tobias Inhoff
- Department of Medicine, Division Hepatology, Gastroenterology, and Endocrinology; Charité, Campus Virchow; Universitätsmedizin Berlin, Germany
| | - Reinhardt Lommel
- Department of Medicine, Division Psychosomatic Medicine and Psychotherapy; Charité, Campus Mitte; Universitätsmedizin Berlin, Germany
| | - Andreas Stengel
- Department of Medicine, Division Psychosomatic Medicine and Psychotherapy; Charité, Campus Mitte; Universitätsmedizin Berlin, Germany
- Department of Medicine, Division of Digestive Diseases, CURE Digestive Diseases Research Center and Center for Neurobiology of Stress, UCLA and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Yvette Taché
- Department of Medicine, Division of Digestive Diseases, CURE Digestive Diseases Research Center and Center for Neurobiology of Stress, UCLA and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Carsten Grötzinger
- Department of Medicine, Division Hepatology, Gastroenterology, and Endocrinology; Charité, Campus Virchow; Universitätsmedizin Berlin, Germany
| | | | - Bertram Wiedenmann
- Department of Medicine, Division Hepatology, Gastroenterology, and Endocrinology; Charité, Campus Virchow; Universitätsmedizin Berlin, Germany
| | - Burghard F. Klapp
- Department of Medicine, Division Psychosomatic Medicine and Psychotherapy; Charité, Campus Mitte; Universitätsmedizin Berlin, Germany
| | - Peter Kobelt
- Department of Medicine, Division Psychosomatic Medicine and Psychotherapy; Charité, Campus Mitte; Universitätsmedizin Berlin, Germany
- Department of Medicine, Division Hepatology, Gastroenterology, and Endocrinology; Charité, Campus Virchow; Universitätsmedizin Berlin, Germany
- Correspondence: Peter Kobelt, PhD Department of Medicine, Division Psychosomatic Medicine and Psychotherapy Charité – Universitätsmedizin Berlin, Campus Mitte Luisenstraße 13 A 10117 Berlin, Germany Phone: +49 30 450-559739 Fax: +49 30 450-559939
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Schroeder M, Gelber V, Moran TH, Weller A. Long-term obesity levels in female OLETF rats following time-specific post-weaning food restriction. Horm Behav 2010; 58:844-53. [PMID: 20736013 PMCID: PMC2982947 DOI: 10.1016/j.yhbeh.2010.08.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Revised: 08/15/2010] [Accepted: 08/18/2010] [Indexed: 01/03/2023]
Abstract
Obesity and the metabolic syndrome represent serious health threats affecting increasing numbers of individuals, with females being more affected than males and with growing incidence among children and adolescents. In the present study, we used the OLETF rat model of early-onset obesity to examine the influence of different timing of food restriction on long-term obesity levels in females. Food restriction took place at different time windows: from weaning until postnatal day (PND) 45 (early); from weaning until PND90 (chronic); or from PND45 until PND70 (late). Follow-up continued until PND90. During and after the termination of the diet-restriction period, we focused on peripheral adiposity-related measures such as fat pad weight (brown, retroperitoneal and inguinal); inguinal adipocyte size and number; and leptin, oxytocin and glucose levels. We also examined body weight, feeding efficiency, spontaneous intake after release from diet-restriction, and plasma creatinine levels and estrous cycle characteristics as a result of the chronic diet. The results suggest that while food restriction produced significant weight and adiposity loss, OLETF females presented poor weight loss retention after the early and late short-term diets. The estrous cycle structure and time of first estrous of the OLETF rats were normalized by chronic food restriction. Females responded to early food restriction in a different manner than males did in previous studies, further emphasizing the importance of sex-appropriate approaches in the investigation and treatment of the pathologies related to obesity and the metabolic syndrome.
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Brown LM, Clegg DJ. Central effects of estradiol in the regulation of food intake, body weight, and adiposity. J Steroid Biochem Mol Biol 2010; 122:65-73. [PMID: 20035866 PMCID: PMC2889220 DOI: 10.1016/j.jsbmb.2009.12.005] [Citation(s) in RCA: 224] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2009] [Revised: 11/19/2009] [Accepted: 12/15/2009] [Indexed: 12/14/2022]
Abstract
In recent years, obesity and its associated health disorders and costs have increased. Accumulation of adipose tissue, or fat, in the intra-abdominal adipose depot is associated with an increased risk of developing cardiovascular problems, type-2 diabetes mellitus, certain cancers, and other disorders like the metabolic syndrome. Males and females differ in terms of how and where their body fat is stored, in their hormonal secretions, and in their neural responses to signals regulating weight and body fat distribution. Men and post-menopausal women accumulate more fat in their intra-abdominal depots than pre-menopausal women, resulting in a greater risk of developing complications associated with obesity. The goal of this review is to discuss the current literature on sexual dimorphisms in body weight regulation, adipose tissue accrual and deposition.
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Affiliation(s)
- LM Brown
- Department of Nutrition, University of North Carolina Greensboro, Greensboro, NC 27412
| | - DJ Clegg
- Department of Internal Medicine, Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390-8854
- Corresponding author at: Deborah J. Clegg, RD, PhD, Assistant Professor, Department of Internal Medicine, Touchstone Diabetes Center, UT Southwestern Medical Center, 5323 Harry Hines Blvd., K5.252, Dallas, TX 75390-8854, Tel: 214-648-3401, Fax: 214-648-8720, (D. Clegg)
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Peter L, Stengel A, Noetzel S, Inhoff T, Goebel M, Taché Y, Veh RW, Bannert N, Grötzinger C, Wiedenmann B, Klapp BF, Mönnikes H, Kobelt P. Peripherally injected CCK-8S activates CART positive neurons of the paraventricular nucleus in rats. Peptides 2010; 31:1118-1123. [PMID: 20307613 PMCID: PMC4040251 DOI: 10.1016/j.peptides.2010.03.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 03/10/2010] [Accepted: 03/10/2010] [Indexed: 01/23/2023]
Abstract
Cholecystokinin (CCK) plays a role in the short-term inhibition of food intake. Cocaine- and amphetamine-regulated transcript (CART) peptide has been observed in neurons of the paraventricular nucleus (PVN). It has been reported that intracerebroventricular injection of CART peptide inhibits food intake in rodents. The aim of the study was to determine whether intraperitoneally (ip) injected CCK-8S affects neuronal activity of PVN-CART neurons. Ad libitum fed male Sprague-Dawley rats received 6 or 10 microg/kg CCK-8S or 0.15M NaCl ip (n=4/group). The number of c-Fos-immunoreactive neurons was determined in the PVN, arcuate nucleus (ARC), and the nucleus of the solitary tract (NTS). CCK-8S dose-dependently increased the number of c-Fos-immunoreactive neurons in the PVN (mean+/-SEM: 102+/-6 vs. 150+/-5 neurons/section, p<0.05) and compared to vehicle treated rats (18+/-7, p<0.05 vs. 6 and 10 microg/kg CCK-8S). CCK-8S at both doses induced an increase in the number of c-Fos-immunoreactive neurons in the NTS (65+/-13, p<0.05, and 182+/-16, p<0.05). No effect on the number of c-Fos neurons was observed in the ARC. Immunostaining for CART and c-Fos revealed a dose-dependent increase of activated CART neurons (19+/-3 vs. 29+/-7; p<0.05), only few activated CART neuron were observed in the vehicle group (1+/-0). The present observation shows that CCK-8S injected ip induces an increase in neuronal activity in PVN-CART neurons and suggests that CART neurons in the PVN may play a role in the mediation of peripheral CCK-8S's anorexigenic effects.
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Affiliation(s)
- Lisa Peter
- Department of Medicine, Division Hepatology, Gastroenterology, and Endocrinology, Charité, Campus Virchow, Universitätsmedizin Berlin, Berlin, Germany
| | - Andreas Stengel
- Department of Medicine, Division of Digestive Diseases, CURE Digestive Diseases Research Center and Center for Neurobiology of Stress, UCLA and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Steffen Noetzel
- Department of Medicine, Division Hepatology, Gastroenterology, and Endocrinology, Charité, Campus Virchow, Universitätsmedizin Berlin, Berlin, Germany
| | - Tobias Inhoff
- Department of Medicine, Division Hepatology, Gastroenterology, and Endocrinology, Charité, Campus Virchow, Universitätsmedizin Berlin, Berlin, Germany
| | - Miriam Goebel
- Department of Medicine, Division of Digestive Diseases, CURE Digestive Diseases Research Center and Center for Neurobiology of Stress, UCLA and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Yvette Taché
- Department of Medicine, Division of Digestive Diseases, CURE Digestive Diseases Research Center and Center for Neurobiology of Stress, UCLA and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Rüdiger W. Veh
- Institute for Integrative Neuroanatomy, Charité, Campus Mitte, Universitätsmedizin Berlin, Berlin, Germany
| | | | - Carsten Grötzinger
- Department of Medicine, Division Hepatology, Gastroenterology, and Endocrinology, Charité, Campus Virchow, Universitätsmedizin Berlin, Berlin, Germany
| | - Bertram Wiedenmann
- Department of Medicine, Division Hepatology, Gastroenterology, and Endocrinology, Charité, Campus Virchow, Universitätsmedizin Berlin, Berlin, Germany
| | - Burghard F. Klapp
- Department of Medicine, Division Psychosomatic Medicine and Psychotherapy, Charité, Campus Mitte, Universitätsmedizin Berlin, Berlin, Germany
| | - Hubert Mönnikes
- Department of Medicine and Institute of Neurogastroenterology, Martin-Luther-Hospital, Berlin, Germany
| | - Peter Kobelt
- Department of Medicine, Division Hepatology, Gastroenterology, and Endocrinology, Charité, Campus Virchow, Universitätsmedizin Berlin, Berlin, Germany
- Department of Medicine, Division Psychosomatic Medicine and Psychotherapy, Charité, Campus Mitte, Universitätsmedizin Berlin, Berlin, Germany
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Caquineau C, Douglas AJ, Leng G. Effects of cholecystokinin in the supraoptic nucleus and paraventricular nucleus are negatively modulated by leptin in 24-h fasted lean male rats. J Neuroendocrinol 2010; 22:446-52. [PMID: 20163516 PMCID: PMC2948420 DOI: 10.1111/j.1365-2826.2010.01982.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 01/27/2010] [Accepted: 02/09/2010] [Indexed: 11/30/2022]
Abstract
Cholecystokinin (CCK) and leptin are two important satiety factors that are considered to act in synergy to reduce meal size. Peripheral injection of CCK activates neurones in several hypothalamic nuclei, including the supraoptic (SON) and paraventricular (PVN) nuclei and neurones in the brainstem of fed rats. We investigated whether peripheral leptin would modulate the effects of CCK on neuronal activity in the hypothalamus and brainstem of fasted rats by investigating Fos expression in the PVN, SON, arcuate nucleus, ventromedial hypothalamus (VMH), dorsomedial hypothalamus (DMH), area postrema (AP) and the nucleus tractus solitarii (NTS). Male rats, fasted for 24 h, received either one i.p. injection of vehicle, leptin or CCK-8 alone, or received one injection of vehicle or leptin before an i.p. injection of CCK-8. We found that CCK increased Fos expression in the PVN and SON as well as in the NTS and AP, but had no effect on Fos expression in the arcuate nucleus, VMH or DMH compared to vehicle. Leptin injected alone significantly increased Fos expression in the arcuate nucleus but had no effect on Fos expression in the VMH, DMH, SON, PVN, AP or NTS compared to vehicle. Fos expression was significantly increased in the AP in rats injected with both leptin and CCK compared to rats injected with vehicle and CCK. Unexpectedly, there was significantly less Fos expression in the PVN and SON of fasted rats injected with leptin and CCK than in rats injected with vehicle and CCK, suggesting that leptin attenuated CCK-induced Fos expression in the SON and PVN. However, Fos expression in the NTS was similar in fasted rats injected with vehicle and CCK or with leptin and CCK. Taken together, these results suggest that leptin dampens the effects of CCK on Fos expression in the SON and PVN, independently from NTS pathways, and this may reflect a direct action on magnocellular neurones.
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Affiliation(s)
- C Caquineau
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK.
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Schroeder M, Moran TH, Weller A. Attenuation of obesity by early-life food restriction in genetically hyperphagic male OLETF rats: peripheral mechanisms. Horm Behav 2010; 57:455-62. [PMID: 20156441 PMCID: PMC2852576 DOI: 10.1016/j.yhbeh.2010.02.002] [Citation(s) in RCA: 14] [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: 12/06/2009] [Revised: 01/31/2010] [Accepted: 02/07/2010] [Indexed: 11/19/2022]
Abstract
The alarming increase in childhood, adolescent and adult obesity has exposed the need for understanding early factors affecting obesity and for treatments that may help prevent or moderate its development. In the present study, we used the OLETF rat model of early-onset hyperphagia induced obesity, which become obese as a result of the absence of CCK(1) receptors, to examine the influence of partial food restriction on peripheral adiposity-related parameters during and after chronic and early short-term food restriction. Pair feeding (to the amount of food eaten by control, LETO rats) took place from weaning until postnatal day (PND) 45 (early) or from weaning until PND90 (chronic). We examined fat pad weight (brown, retroperitoneal, inguinal and epididymal); inguinal adipocyte size and number; and plasma leptin, oxytocin and creatinine levels. We also examined body weight, feeding efficiency and spontaneous intake after release from food-restriction. The results showed that chronic food restriction produced significant reductions in adiposity parameters, hormones and body weight, while early food restriction successfully reduced long-term body weight, intake and adiposity, without affecting plasma measurements. Early (and chronic) dieting produced promising long-term effects that may imply the reorganization of both peripheral and central mechanisms that determine energy balance and further support the theory suggesting that early interventions may effectively moderate obesity, even in the presence of a genetic tendency.
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Affiliation(s)
- Mariana Schroeder
- Life Sciences Faculty, Bar Ilan University, Ramat Gan 52900, Israel
- Gonda (Goldschmied) Brain Research Center, Bar Ilan University, Ramat Gan 52900, Israel
| | - Timothy H. Moran
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Aron Weller
- Gonda (Goldschmied) Brain Research Center, Bar Ilan University, Ramat Gan 52900, Israel
- Psychology Department, Bar Ilan University, Ramat Gan 52900, Israel
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Banihashemi L, Rinaman L. Repeated brief postnatal maternal separation enhances hypothalamic gastric autonomic circuits in juvenile rats. Neuroscience 2010; 165:265-77. [PMID: 19800939 PMCID: PMC2788015 DOI: 10.1016/j.neuroscience.2009.09.081] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 09/11/2009] [Accepted: 09/30/2009] [Indexed: 02/03/2023]
Abstract
Maternal separation of rat pups for 15 min each day over the first one to two postnatal weeks (MS15) has been shown to increase the active maternal care received by pups and to decrease their later neuroendocrine and behavioral stress reactivity compared to non-separated (NS) controls. Stress responses prominently feature altered gastric secretion and motility, and we previously reported that the developmental assembly of forebrain circuits underlying gastric autonomic control, including gastric responses to stress, is delayed by MS15 in neonatal rats [Card JP, Levitt P, Gluhovsky M, Rinaman L (2005) J Neurosci 25(40):9102-9111]. To determine how this early delay affects the later organization of central gastric autonomic circuits, the present study examined the effects of neonatal MS15 on central pre-gastric circuits assessed in post-weaning, juvenile rats. For this purpose, the retrograde transynaptic viral tracer, pseudorabies virus (PRV), was microinjected into the stomach wall of 28-30 day old male rats with an earlier developmental history of either MS15 or NS. Rats were perfused 72 h later and tissue was processed to reveal PRV-positive cells. Transynaptic PRV immunolabeling was quantified in selected preautonomic brainstem and forebrain regions, including the area postrema, bed nucleus of the stria terminalis, central nucleus of the amygdala, paraventricular nucleus of the hypothalamus (PVN), and visceral cortices. Compared to NS controls, MS15 rats displayed a significantly greater amount of PRV labeling within the PVN, including both the dorsal cap and ventral subnuclei. There were no postnatal group differences in the amount of PRV labeling within any other brain region examined in this study. This effect of MS15 to enhance hypothalamic preautonomic circuit structure indicates a strengthening of this pathway and may provide insight into how early life experience produces differential effects on later stress reactivity, including gastric secretory and motor responses to stress.
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Affiliation(s)
- L Banihashemi
- Department of Neuroscience, University of Pittsburgh, PA 15260, USA.
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39
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Duplan SM, Boucher F, Alexandrov L, Michaud JL. Impact of Sim1 gene dosage on the development of the paraventricular and supraoptic nuclei of the hypothalamus. Eur J Neurosci 2009; 30:2239-49. [DOI: 10.1111/j.1460-9568.2009.07028.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
It is now axiomatic that neurons in the hypothalamic arcuate nucleus have a primary role in responding to changes in circulating levels of leptin and transmitting signals to downstream circuits that influence eating and energy expenditure. Signals generated from the gastrointestinal tract during meals reach the brainstem, via the vagus nerve and other routes, and impinge on neural circuits that influence the timing and size of meals and amount of food consumed. One of the mechanisms by which leptin exerts its anorexic effects is by increasing the effectiveness of intestinal signals that cause satiation during a meal. It is clear that the effects of gut satiation signals such as CCK can be amplified by leptin acting in the CNS, and in the arcuate nucleus in particular. The present article describes the state of our knowledge about specific neural circuits between the hypothalamus and brainstem that play a role in the interaction of leptin and meal-control signals to control food intake.
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Uchoa ET, Mendes da Silva LEC, de Castro M, Antunes-Rodrigues J, Elias LLK. Hypothalamic oxytocin neurons modulate hypophagic effect induced by adrenalectomy. Horm Behav 2009; 56:532-8. [PMID: 19778539 DOI: 10.1016/j.yhbeh.2009.09.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Revised: 09/04/2009] [Accepted: 09/13/2009] [Indexed: 10/20/2022]
Abstract
Glucocorticoids have major effects on food intake, as demonstrated by the decrease of food intake following adrenalectomy (ADX); however, the mechanisms leading to these effects are not well understood. Oxytocin (OT) has been shown to reduce food intake. We evaluated the effects of glucocorticoids on OT neuron activation and OT mRNA expression in the hypothalamic paraventricular (PVN) and supraoptic (SON) nuclei induced by feeding. We also evaluated the effect of pretreatment with OT-receptor antagonist ([d(CH2)5,Tyr(Me)2,Orn8]-vasotocin, OVT) on food intake in ADX rats. Fos/OT neurons in the posterior parvocellular subdivision of the PVN were increased after refeeding, with a higher number in the ADX group, compared with sham and ADX+corticosterone (B) groups, with no difference in the medial parvocellular and magnocellular subdivisions of the PVN. ADX increased OT mRNA expression in the PVN both in fasting and refeeding condition, compared with sham and ADX+B groups. In the SON, refeeding increased the number of Fos/OT neurons, with a higher number in the ADX+B group. In fasted condition, OT mRNA expression in the SON was increased in ADX and ADX+B, compared with sham group. Pretreatment with OVT reversed the ADX-induced hypophagia, with no difference between sham and ADX+B animals. The present results show that glucocorticoid withdrawal induces a higher activation of PVN OT neurons in response to feeding, and an increase of OT mRNA expression in the PVN and OT-receptor antagonist reverses the anorexigenic effect induced by ADX. These data indicate that PVN OT neurons might mediate the hypophagic effect induced by adrenalectomy.
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Affiliation(s)
- Ernane Torres Uchoa
- Department of Physiology, School of Medicine of Ribeirao Preto, University of São Paulo, São Paulo, Brazil
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42
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CCK-8S activates c-Fos in a dose-dependent manner in nesfatin-1 immunoreactive neurons in the paraventricular nucleus of the hypothalamus and in the nucleus of the solitary tract of the brainstem. ACTA ACUST UNITED AC 2009; 157:84-91. [DOI: 10.1016/j.regpep.2009.06.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2009] [Revised: 06/02/2009] [Accepted: 06/12/2009] [Indexed: 01/16/2023]
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Schroeder M, Zagoory-Sharon O, Shbiro L, Marco A, Hyun J, Moran TH, Bi S, Weller A. Development of obesity in the Otsuka Long-Evans Tokushima Fatty rat. Am J Physiol Regul Integr Comp Physiol 2009; 297:R1749-60. [PMID: 19793959 DOI: 10.1152/ajpregu.00461.2009] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Understanding the early factors affecting obesity development in males and females may help to prevent obesity and may lead to the discovery of more effective treatments for those already obese. The Otsuka Long-Evans Tokushima Fatty (OLETF) rat model of obesity is characterized by hyperphagia-induced obesity, due to a spontaneous lack of CCK(1) receptors. In the present study, we focused on the behavioral and physiological aspects of obesity development from weaning to adulthood. We examined body weight, feeding efficiency, fat pad [brown, retroperitoneal, inguinal and epydidimal (in males)] weight, inguinal adipocyte size and number, leptin and oxytocin levels, body mass index, waist circumference, and females' estrous cycle structure. In the males, central hypothalamic gene expression was also examined. OLETF rats presented overall higher fat and leptin levels, larger adipocytes, and increased waist circumference and BMI from weaning until adulthood, compared with controls. Analysis of developmental patterns of gene expression for hypothalamic neuropeptides revealed peptide-specific patterns that may underlie or be a consequence of the obesity development. Analysis of the developmental trajectories toward obesity within the OLETF strain revealed that OLETF females developed obesity in a more gradual manner than the males, presenting delayed obesity-related "turning points," with reduced adipocyte size but larger postweaning fat pads and increased adipocyte hyperplasia compared with the males. Intake decrease in estrus vs. proestrus was significantly less in OLETF vs. Long-Evans Tokushima Otsuka females. The findings highlight the importance of using different sex-appropriate approaches to increase the efficacy of therapeutic interventions in the treatment and prevention of chronic early-onset obesity.
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Horn CC. Brain Fos expression induced by the chemotherapy agent cisplatin in the rat is partially dependent on an intact abdominal vagus. Auton Neurosci 2009; 148:76-82. [PMID: 19362521 PMCID: PMC3327482 DOI: 10.1016/j.autneu.2009.03.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2008] [Revised: 03/09/2009] [Accepted: 03/19/2009] [Indexed: 10/20/2022]
Abstract
Anticancer agents such as cisplatin stimulate nausea, vomiting, and behaviors indicative of malaise. Rats and mice, and probably all rodents, do not possess a vomiting response, and their ingestion of kaolin clay (a pica response) has been used as an index of malaise. Similar to the action of cisplatin on emesis in vomiting species, in the rat cisplatin activates vagal afferent fibers, and cisplatin-induced kaolin intake is largely dependent on an intact abdominal vagus. Cisplatin also stimulates Fos expression in the rat brain in areas known to play a role in emesis in other species, but it is not known whether vagal input is required for this CNS activation. In the present study, rats were given abdominal vagotomy or sham operation to test the role of an intact vagus on cisplatin-induced Fos expression 6 h after injection with saline or cisplatin (6 mg/kg, ip). Cisplatin treatment produced Fos expression in the area postrema and multiple levels of the nucleus of the solitary tract (NTS) of sham-operated rats. Vagotomy reduced cisplatin-induced Fos expression in the caudal and middle levels of the NTS and central amygdala. Furthermore, cisplatin did not significantly alter Fos expression in the spinal cord (T8-T10) before or after vagotomy. These results suggest that a defined portion of cisplatin-induced Fos expression is dependent on vagal input, with a majority of this response determined by either direct action of cisplatin or humoral factors on the CNS.
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Affiliation(s)
- Charles C Horn
- Monell Chemical Senses Center, Philadelphia, PA 19104, USA.
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Qin J, Feng M, Wang C, Ye Y, Wang PS, Liu C. Oxytocin receptor expressed on the smooth muscle mediates the excitatory effect of oxytocin on gastric motility in rats. Neurogastroenterol Motil 2009; 21:430-8. [PMID: 19309416 DOI: 10.1111/j.1365-2982.2009.01282.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The aim of this study was to localize oxytocin receptor (OTR) in the stomach and to investigate the effect of OT on gastric motility in rats. Western blot and immunohistochemistry methods were used to localize OTR in stomach. The motility of stomach was recorded in vivo (recording of the intragastric pressure), in vitro (recording of the contraction of muscle strips) and on isolated smooth muscle cells. OTR was expressed on cells of both circular and longitudinal muscle of stomach. Systemic administration of OT induced an early transient decrease and a subsequent increase on intragastric pressure. Devazepide (1 mg kg(-1), i.v.), a cholecystokinin-1 (CCK(1)) receptor antagonist, completely abolished the transient response but did not influence the subsequent one. OT (10(-9)-10(-6) mol L(-1)) dose-dependently increased the contraction of the muscle strips of gastric body, antrum, and pyloric sphincter, and decreased the average cell length of isolated smooth muscle cells. Tetrodotoxin and atropine did not influence the effect of OT on muscle strips. Pretreatment with atosiban, an OTR antagonist, inhibited the spontaneous contraction of muscle strips and abolished the excitatory effect of OT on the muscle strips and the isolated cells. These results suggest that the OTR is expressed on the smooth muscle of the stomach and mediates excitatory effect of OT on gastric motility.
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Affiliation(s)
- J Qin
- Department of Physiology, Shandong University School of Medicine, Jinan, China
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De Jonghe BC, Horn CC. Chemotherapy agent cisplatin induces 48-h Fos expression in the brain of a vomiting species, the house musk shrew (Suncus murinus). Am J Physiol Regul Integr Comp Physiol 2009; 296:R902-11. [PMID: 19225146 DOI: 10.1152/ajpregu.90952.2008] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cancer chemotherapy drugs, such as cisplatin, potently produce nausea and vomiting. Acute effects of these treatments are partly controlled by antiemetic drugs, but the delayed effects (>24 h), especially nausea, are more difficult to treat. It is unknown what brain pathways produce this delayed sickness. Our prior data show that brain Fos expression is increased for at least 48 h after cisplatin treatment in the rat, a nonvomiting species. Here, we extend these observations by using house musk shrews (Suncus murinus), a species with an emetic response. Compared with saline injection, cisplatin treatment (30 mg/kg ip) induced Fos expression in hindbrain areas known to play a role in the generation of emesis, the dorsal motor nucleus (DMN), the area postrema, and the nucleus of the solitary tract (NTS), for up to 48 h. Cisplatin also stimulated Fos expression in the parabrachial nucleus (PBN) of the midbrain and the central nucleus of the amygdala (CeA) for at least 48 h after treatment. When animals were pretreated with the antiemetic palonosetron, a long-term serotonin type 3 (5-HT(3)) receptor antagonist, cisplatin-induced Fos expression was significantly attenuated in the NTS, DMN, and CeA at 6 h but not at 48 h. These results indicate that cisplatin activates a neural system that includes the dorsal vagal complex and forebrain in the musk shrew, which is partially suppressed by a 5-HT(3) receptor antagonist. Our findings suggest the existence of an extensive neural system that could be targeted to reduce nausea, vomiting, and malaise in cancer patients receiving chemotherapy.
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Kobelt P, Wisser AS, Stengel A, Goebel M, Bannert N, Gourcerol G, Inhoff T, Noetzel S, Wiedenmann B, Klapp BF, Taché Y, Mönnikes H. Peripheral obestatin has no effect on feeding behavior and brain Fos expression in rodents. Peptides 2008; 29:1018-27. [PMID: 18342400 PMCID: PMC2669739 DOI: 10.1016/j.peptides.2008.01.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Revised: 01/25/2008] [Accepted: 01/30/2008] [Indexed: 01/17/2023]
Abstract
Obestatin is produced in the stomach from proghrelin by post-translational cleavage. The initial report claimed anorexigenic effects of obestatin in mice. Contrasting studies indicated no effect of obestatin on food intake (FI). We investigated influences of metabolic state (fed/fasted), environmental factors (dark/light phase) and brain Fos response to intraperitoneal (ip) obestatin in rats, and used the protocol from the original study assessing obestatin effects in mice. FI was determined in male rats injected ip before onset of dark or light phase, with obestatin (1 or 5 micromol/kg), CCK8S (3.5 nmol/kg) or 0.15 M NaCl, after fasting (16 h, n=8/group) or ad libitum (n=10-14/group) food intake. Fos expression in hypothalamic and brainstem nuclei was examined in freely fed rats 90 min after obestatin (5 micromol/kg), CCK8S (1.75 nmol/kg) or 0.15 M NaCl (n=4/group). Additionally, fasted mice were injected ip with obestatin (1 micromol/kg) or urocortin 1 (2 nmol/kg) 15 min before food presentation. No effect on FI was observed after obestatin administration during the light and dark phase under both metabolic conditions while CCK8S reduced FI irrespectively of the conditions. The number of Fos positive neurons was not modified by obestatin while CCK8S increased Fos expression in selective brain nuclei. Obestatin did not influence the refeeding response to a fast in mice, while urocortin was effective. Therefore, peripheral obestatin has no effect on FI under various experimental conditions and did not induce Fos in relevant central neuronal circuitries modulating feeding in rodents.
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Affiliation(s)
- Peter Kobelt
- Department of Medicine, Division Psychosomatic Medicine and Psychotherapy, Charité-Universitätsmedizin Berlin, Campus Charité Mitte, Berlin, Germany
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48
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Işeri SO, Gedik IE, Erzik C, Uslu B, Arbak S, Gedik N, Yeğen BC. Oxytocin ameliorates skin damage and oxidant gastric injury in rats with thermal trauma. Burns 2008; 34:361-9. [PMID: 17826914 DOI: 10.1016/j.burns.2007.03.022] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2006] [Accepted: 03/29/2007] [Indexed: 11/29/2022]
Abstract
Transient splanchnic vasoconstriction following major burns causes oxidative and/or nitrosative damage in gastrointestinal tissues due to ischemia, which is followed by reperfusion injury. Oxytocin (OT), a hypothalamic nonapeptide, possesses antisecretory and antiulcer effects, facilitates wound healing and is involved in immune and inflammatory processes. To assess the possible protective effect of oxytocin (OT) against burn-induced gastric injury, Sprague-Dawley rats (250-300g) were randomly divided into three groups as control (n=8), OT-treated burn (n=8) and saline-treated burn (n=8) groups. Under anesthesia, the shaved dorsal skin of rats was exposed to 90 degrees C water for 10s to induce burn injury covering 30% of total body surface area in a standardized manner. Either oxytocin (5microg/kg) or saline was administered subcutaneously immediately after and at 24h following burn, and the rats were decapitated at 48h. Serum samples were assayed for TNF-alpha, and stomach was taken for the determination of malondialdehyde (MDA), myeloperoxidase (MPO) activity, DNA fragmentation rate (%) and histopathological examination. MDA and MPO were assayed for products of lipid peroxidation and as an index of tissue neutrophil infiltration, respectively. When compared to control group, burn caused significant increases in gastric MDA and MPO activity and increased microscopic damage scores at 48h (p<0.001). Oxytocin treatment reversed the burn-induced elevations in MDA and MPO levels and reduced the gastric damage scores (p<0.001, p<0.01), while TNF-alpha levels, which were increased significantly at 48thh after injury (p<0.001), were abolished with OT treatment (p<0.001). The results of this study suggest that oxytocin may provide a therapeutic benefit in diminishing burn-induced gastric inflammation by depressing tissue neutrophil infiltration and decreasing the release of inflammatory cytokines, but requires further investigation as a potential therapeutic agent in ameliorating the systemic effects of severe burn.
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Affiliation(s)
- Sevgin Ozlem Işeri
- Marmara University, School of Medicine, Department of Physiology, Haydarpaşa, Istanbul 34668, Turkey
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49
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Kublaoui BM, Gemelli T, Tolson KP, Wang Y, Zinn AR. Oxytocin deficiency mediates hyperphagic obesity of Sim1 haploinsufficient mice. Mol Endocrinol 2008; 22:1723-34. [PMID: 18451093 DOI: 10.1210/me.2008-0067] [Citation(s) in RCA: 187] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Single-minded 1 (Sim1) encodes a transcription factor essential for formation of the hypothalamic paraventricular nucleus (PVN). Sim1 haploinsufficiency is associated with hyperphagic obesity and increased linear growth in humans and mice, similar to the phenotype of melanocortin 4 receptor (Mc4r) mutations. PVN neurons in Sim1(+/-) mice are hyporesponsive to the melanocortin agonist melanotan II. PVN neuropeptides oxytocin (Oxt), TRH and CRH inhibit feeding when administered centrally. Consequently, we hypothesized that altered PVN neuropeptide expression mediates the hyperphagia of Sim1(+/-) mice. To test this hypothesis, we measured hypothalamic expression of PVN neuropeptides in Sim1(+/-) and wild-type mice. Oxt mRNA and peptide were decreased by 80% in Sim1(+/-) mice, whereas TRH, CRH, arginine vasopressin (Avp), and somatostatin mRNAs were decreased by 20-40%. Sim1(+/-) mice also showed abnormal regulation of Oxt but not CRH mRNA in response to feeding state. A selective Mc4r agonist activated PVN Oxt neurons in wild-type mice, supporting involvement of these neurons in melanocortin feeding circuits. To test whether Oxt itself regulates feeding, we measured the effects of central administration of an Oxt receptor antagonist or repeated doses of Oxt on food intake of Sim1(+/-) and wild-type mice. Sim1(+/-) mice were hypersensitive to the orexigenic effect of the Oxt receptor antagonist. Oxt decreased the food intake and weight gain of Sim1(+/-) mice at a dose that did not affect wild-type mice. Our results support the importance of Oxt neurons in feeding regulation and suggest that reduced Oxt neuropeptide is one mechanism mediating the hyperphagic obesity of Sim1(+/-) mice.
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Affiliation(s)
- Bassil M Kublaoui
- Department of Pediatrics, Department of Internal Medicine, McDermott Center for Human Growth and Development, The University of Texas Southwestern Medical School, Dallas, TX 75390-8591, USA.
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Hoyda TD, Fry M, Ahima RS, Ferguson AV. Adiponectin selectively inhibits oxytocin neurons of the paraventricular nucleus of the hypothalamus. J Physiol 2007; 585:805-16. [PMID: 17947308 DOI: 10.1113/jphysiol.2007.144519] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Adiponectin is an adipocyte derived hormone which acts in the brain to modulate energy homeostasis and autonomic function. The paraventricular nucleus of the hypothalamus (PVN) which plays a key role in controlling pituitary hormone secretion has been suggested to be a central target for adiponectin actions. A number of hormones produced by PVN neurons have been implicated in the regulation of energy homeostasis including oxytocin, corticotropin releasing hormone and thyrotropin releasing hormone. In the present study we investigated the role of adiponectin in controlling the excitability of magnocellular (MNC--oxytocin or vasopressin secreting) neurons within the PVN. Using RT-PCR techniques we have shown expression of both adiponectin receptors in the PVN. Patch clamp recordings from MNC neurons in hypothalamic slices have also identified mixed (27% hyperpolarization, 42% depolarization) effects of adiponectin in modulating the excitability of the majority of MNC neurons tested. These effects are maintained when cells are placed in synaptic isolation using tetrodotoxin. Additionally we combined electrophysiological recordings with single cell RT-PCR to examine the actions of adiponectin on MNC neurons which expressed oxytocin only, vasopressin only, or both oxytocin and vasopressin mRNA and assess the profile of receptor expression in these subgroups. Adiponectin was found to hyperpolarize 100% of oxytocin neurons tested (n = 6), while vasopressin cells, while all affected (n = 6), showed mixed responses. Further analysis indicates oxytocin neurons express both receptors (6/7) while vasopressin neurons express either both receptors (3/8) or one receptor (5/8). In contrast 6/6 oxytocin/vasopressin neurons were unaffected by adiponectin. Co-expressing oxytocin and vasopressin neurons express neither receptor (4/6). The results presented in this study suggest that adiponectin plays specific roles in controlling the excitability oxytocin secreting neurons, actions which correlate with the current literature showing increased oxytocin secretion in the obese population.
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Affiliation(s)
- Ted D Hoyda
- Department of Physiology, Faculty of Life Sciences, Queen's University, 18 Stuart Street, Kingston, Ontario, Canada
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