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Lord MN, Subramanian K, Kanoski SE, Noble EE. Melanin-concentrating hormone and food intake control: Sites of action, peptide interactions, and appetition. Peptides 2021; 137:170476. [PMID: 33370567 PMCID: PMC8025943 DOI: 10.1016/j.peptides.2020.170476] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 12/10/2020] [Accepted: 12/14/2020] [Indexed: 12/12/2022]
Abstract
Given the increased prevalence of obesity and its associated comorbidities, understanding the mechanisms through which the brain regulates energy balance is of critical importance. The neuropeptide melanin-concentrating hormone (MCH) is produced in the lateral hypothalamic area and the adjacent incerto-hypothalamic area and promotes both food intake and energy conservation, overall contributing to body weight gain. Decades of research into this system has provided insight into the neural pathways and mechanisms (behavioral and neurobiological) through which MCH stimulates food intake. Recent technological advancements that allow for selective manipulation of MCH neuron activity have elucidated novel mechanisms of action for the hyperphagic effects of MCH, implicating neural "volume" transmission in the cerebrospinal fluid and sex-specific effects of MCH on food intake control as understudied areas for future investigation. Highlighted here are historical and recent findings that illuminate the neurobiological mechanisms through which MCH promotes food intake, including the identification of various specific neural signaling pathways and interactions with other peptide systems. We conclude with a framework that the hyperphagic effects of MCH signaling are predominantly mediated through enhancement of an "appetition" process in which early postoral prandial signals promote further caloric consumption.
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Affiliation(s)
- Magen N Lord
- Department of Foods and Nutrition, University of Georgia, Athens, GA 30606, USA
| | - Keshav Subramanian
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA 90089, USA
| | - Scott E Kanoski
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA 90089, USA; Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA.
| | - Emily E Noble
- Department of Foods and Nutrition, University of Georgia, Athens, GA 30606, USA.
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2
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Exosomes: Their Role in Pathogenesis, Diagnosis and Treatment of Diseases. Cancers (Basel) 2020; 13:cancers13010084. [PMID: 33396739 PMCID: PMC7795854 DOI: 10.3390/cancers13010084] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 12/18/2020] [Accepted: 12/24/2020] [Indexed: 02/07/2023] Open
Abstract
Simple Summary The aim of this review is to provide an overview of the current scientific evidence concerning the role played by exosomes in the pathogenesis, diagnosis and treatment of diseases. The potential use of exosomes as delivery vectors for small-molecule therapeutic agents will be discussed. In addition, a special emphasis will be placed on the involvement of exosomes in oncological diseases, as well as to their potential therapeutic application as liquid biopsy tools mainly in cancer diagnosis. A better understanding of exosome biology could improve the results of clinical interventions using exosomes as therapeutic agents. Abstract Exosomes are lipid bilayer particles released from cells into their surrounding environment. These vesicles are mediators of near and long-distance intercellular communication and affect various aspects of cell biology. In addition to their biological function, they play an increasingly important role both in diagnosis and as therapeutic agents. In this paper, we review recent literature related to the molecular composition of exosomes, paying special attention to their role in pathogenesis, along with their application as biomarkers and as therapeutic tools. In this context, we analyze the potential use of exosomes in biomedicine, as well as the limitations that preclude their wider application.
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Seoane-Collazo P, Diéguez C, Nogueiras R, Rahmouni K, Fernández-Real JM, López M. Nicotine' actions on energy balance: Friend or foe? Pharmacol Ther 2020; 219:107693. [PMID: 32987056 DOI: 10.1016/j.pharmthera.2020.107693] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 09/21/2020] [Indexed: 12/12/2022]
Abstract
Obesity has reached pandemic proportions and is associated with severe comorbidities, such as type 2 diabetes mellitus, hepatic and cardiovascular diseases, and certain cancer types. However, the therapeutic options to treat obesity are limited. Extensive epidemiological studies have shown a strong relationship between smoking and body weight, with non-smokers weighing more than smokers at any age. Increased body weight after smoking cessation is a major factor that interferes with their attempts to quit smoking. Numerous controlled studies in both humans and rodents have reported that nicotine, the main bioactive component of tobacco, exerts a marked anorectic action. Furthermore, nicotine is also known to modulate energy expenditure, by regulating the thermogenic activity of brown adipose tissue (BAT) and the browning of white adipose tissue (WAT), as well as glucose homeostasis. Many of these actions occur at central level, by controlling the activity of hypothalamic neuropeptide systems such as proopiomelanocortin (POMC), or energy sensors such as AMP-activated protein kinase (AMPK). However, direct impact of nicotine on metabolic tissues, such as BAT, WAT, liver and pancreas has also been described. Here, we review the actions of nicotine on energy balance. The relevance of this interaction is interesting, because considering the restricted efficiency of obesity treatments, a possible complementary approach may focus on compounds with known pharmacokinetic profile and pharmacological actions, such as nicotine or nicotinic acetylcholine receptors signaling.
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Affiliation(s)
- Patricia Seoane-Collazo
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela 15782, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), 15706, Spain; International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan.
| | - Carlos Diéguez
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela 15782, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), 15706, Spain
| | - Rubén Nogueiras
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela 15782, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), 15706, Spain
| | - Kamal Rahmouni
- Department of Neuroscience and Pharmacology, University of Iowa Carver College of Medicine and Veterans Affairs Health Care System, Iowa City, IA 52242, USA
| | - José Manuel Fernández-Real
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), 15706, Spain; Institut d'Investigació Biomèdica de Girona (IDIBGI), Girona, Spain; Department of Diabetes, Endocrinology and Nutrition (UDEN), Hospital of Girona "Dr Josep Trueta" and Department of Medical Sciences, Faculty of Medicine, University of Girona, Girona, Spain
| | - Miguel López
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela 15782, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), 15706, Spain.
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4
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Gumbs MCR, Eggels L, Kool T, Unmehopa UA, van den Heuvel JK, Lamuadni K, Mul JD, la Fleur SE. Neuropeptide Y Signaling in the Lateral Hypothalamus Modulates Diet Component Selection and is Dysregulated in a Model of Diet-Induced Obesity. Neuroscience 2019; 447:28-40. [PMID: 31887359 DOI: 10.1016/j.neuroscience.2019.12.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 01/16/2023]
Abstract
The preclinical multicomponent free-choice high-fat high-sucrose (fcHFHS) diet has strong validity to model diet-induced obesity (DIO) and associated maladaptive molecular changes in the central nervous system. fcHFHS-induced obese rats demonstrate increased sensitivity to intracerebroventricular infusion of the orexigenic Neuropeptide Y (NPY). The brain region-specific effects of NPY signaling on fcHFHS diet component selection are not completely understood. For example, fcHFHS-fed rats have increased intake of chow and fat following intracerebroventricular NPY infusion, whereas NPY administration in the nucleus accumbens, a key hub of the reward circuitry, specifically increases fat intake. Here, we investigated whether NPY infusion in the lateral hypothalamic area (LHA), which is crucially involved in the regulation of intake, regulates fcHFHS component selection, and if LHA NPY receptor subtypes 1 or 5 (NPYR1/5) are involved. Male Wistar rats were fed a chow or fcHFHS diet for at least seven days, and received intra-LHA vehicle or NPY infusions in a cross-over design. Diet component intake was measured two hours later. Separate experimental designs were used to test the efficacy of NPY1R- or NPY5R antagonism to prevent the orexigenic effects of intra-LHA NPY. Intra-LHA NPY increased caloric intake in chow- and fcHFHS-fed rats. This effect was mediated specifically by chow intake in fcHFHS-fed rats. The orexigenic effects of intra-LHA NPY were prevented by NPY1R and NPY5R antagonism in chow-fed rats, but only by NPY5R antagonism in fcHFHS-fed rats. Thus, NPY signaling has brain region-specific effects on fcHFHS component selection and LHA NPYR sensitivity is dysregulated during consumption of a fcHFHS diet.
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Affiliation(s)
- M C R Gumbs
- Amsterdam UMC, University of Amsterdam, Department of Endocrinology and Metabolism and Laboratory of Endocrinology, Department of Clinical Chemistry, Amsterdam Neuroscience, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; Metabolism and Reward Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), Meibergdreef 47, 1105 BA Amsterdam, The Netherlands
| | - L Eggels
- Amsterdam UMC, University of Amsterdam, Department of Endocrinology and Metabolism and Laboratory of Endocrinology, Department of Clinical Chemistry, Amsterdam Neuroscience, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; Metabolism and Reward Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), Meibergdreef 47, 1105 BA Amsterdam, The Netherlands
| | - T Kool
- Amsterdam UMC, University of Amsterdam, Department of Endocrinology and Metabolism and Laboratory of Endocrinology, Department of Clinical Chemistry, Amsterdam Neuroscience, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - U A Unmehopa
- Amsterdam UMC, University of Amsterdam, Department of Endocrinology and Metabolism and Laboratory of Endocrinology, Department of Clinical Chemistry, Amsterdam Neuroscience, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - J K van den Heuvel
- Amsterdam UMC, University of Amsterdam, Department of Endocrinology and Metabolism and Laboratory of Endocrinology, Department of Clinical Chemistry, Amsterdam Neuroscience, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - K Lamuadni
- Amsterdam UMC, University of Amsterdam, Department of Endocrinology and Metabolism and Laboratory of Endocrinology, Department of Clinical Chemistry, Amsterdam Neuroscience, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; Metabolism and Reward Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), Meibergdreef 47, 1105 BA Amsterdam, The Netherlands
| | - J D Mul
- Amsterdam UMC, University of Amsterdam, Department of Endocrinology and Metabolism and Laboratory of Endocrinology, Department of Clinical Chemistry, Amsterdam Neuroscience, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; Metabolism and Reward Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), Meibergdreef 47, 1105 BA Amsterdam, The Netherlands; Brain Plasticity Group, Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Sciencepark 904, 1098 XH Amsterdam, The Netherlands
| | - S E la Fleur
- Amsterdam UMC, University of Amsterdam, Department of Endocrinology and Metabolism and Laboratory of Endocrinology, Department of Clinical Chemistry, Amsterdam Neuroscience, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; Metabolism and Reward Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), Meibergdreef 47, 1105 BA Amsterdam, The Netherlands.
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Al-Massadi O, Quiñones M, Clasadonte J, Hernandez-Bautista R, Romero-Picó A, Folgueira C, Morgan DA, Kalló I, Heras V, Senra A, Funderburk SC, Krashes MJ, Souto Y, Fidalgo M, Luquet S, Chee MJ, Imbernon M, Beiroa D, García-Caballero L, Gallego R, Lam BYH, Yeo G, Lopez M, Liposits Z, Rahmouni K, Prevot V, Dieguez C, Nogueiras R. MCH Regulates SIRT1/FoxO1 and Reduces POMC Neuronal Activity to Induce Hyperphagia, Adiposity, and Glucose Intolerance. Diabetes 2019; 68:2210-2222. [PMID: 31530579 PMCID: PMC6868473 DOI: 10.2337/db19-0029] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 09/03/2019] [Indexed: 12/20/2022]
Abstract
Melanin-concentrating hormone (MCH) is an important regulator of food intake, glucose metabolism, and adiposity. However, the mechanisms mediating these actions remain largely unknown. We used pharmacological and genetic approaches to show that the sirtuin 1 (SIRT1)/FoxO1 signaling pathway in the hypothalamic arcuate nucleus (ARC) mediates MCH-induced feeding, adiposity, and glucose intolerance. MCH reduces proopiomelanocortin (POMC) neuronal activity, and the SIRT1/FoxO1 pathway regulates the inhibitory effect of MCH on POMC expression. Remarkably, the metabolic actions of MCH are compromised in mice lacking SIRT1 specifically in POMC neurons. Of note, the actions of MCH are independent of agouti-related peptide (AgRP) neurons because inhibition of γ-aminobutyric acid receptor in the ARC did not prevent the orexigenic action of MCH, and the hypophagic effect of MCH silencing was maintained after chemogenetic stimulation of AgRP neurons. Central SIRT1 is required for MCH-induced weight gain through its actions on the sympathetic nervous system. The central MCH knockdown causes hypophagia and weight loss in diet-induced obese wild-type mice; however, these effects were abolished in mice overexpressing SIRT1 fed a high-fat diet. These data reveal the neuronal basis for the effects of MCH on food intake, body weight, and glucose metabolism and highlight the relevance of SIRT1/FoxO1 pathway in obesity.
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Affiliation(s)
- Omar Al-Massadi
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Mar Quiñones
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
- Unité de Biologie Fonctionnelle et Adaptative, CNRS UMR 8251, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Jerome Clasadonte
- INSERM, U1172, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, Lille, France
- FHU 1000 Days for Health, School of Medicine, University of Lille, Lille, France
| | - René Hernandez-Bautista
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
| | - Amparo Romero-Picó
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Cintia Folgueira
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Donald A Morgan
- Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, and Iowa City VA Health Care System, Iowa City, IA
| | - Imre Kalló
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Violeta Heras
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Ana Senra
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
| | - Samuel C Funderburk
- Diabetes, Endocrinology, and Obesity Branch, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD
| | - Michael J Krashes
- Diabetes, Endocrinology, and Obesity Branch, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD
| | - Yara Souto
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
| | - Miguel Fidalgo
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
| | - Serge Luquet
- Unité de Biologie Fonctionnelle et Adaptative, CNRS UMR 8251, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Melissa J Chee
- Division of Endocrinology, Beth Israel Deaconess Medical Center, Department of Medicine, Harvard Medical School, Boston, MA
| | - Monica Imbernon
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
- INSERM, U1172, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, Lille, France
| | - Daniel Beiroa
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Lucía García-Caballero
- Department of Morphological Sciences, School of Medicine, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
| | - Rosalia Gallego
- Department of Morphological Sciences, School of Medicine, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
| | - Brian Y H Lam
- MRC Metabolic Diseases Unit, Wellcome-MRC Institute of Metabolic Science-Metabolic Research Laboratories, University of Cambridge, and Addenbrooke's Hospital, Cambridge, U.K
| | - Giles Yeo
- MRC Metabolic Diseases Unit, Wellcome-MRC Institute of Metabolic Science-Metabolic Research Laboratories, University of Cambridge, and Addenbrooke's Hospital, Cambridge, U.K
| | - Miguel Lopez
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Zsolt Liposits
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Kamal Rahmouni
- Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, and Iowa City VA Health Care System, Iowa City, IA
| | - Vincent Prevot
- INSERM, U1172, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Center, Lille, France
- FHU 1000 Days for Health, School of Medicine, University of Lille, Lille, France
| | - Carlos Dieguez
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Ruben Nogueiras
- Department of Physiology, CIMUS, Universidad de Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
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Sanathara NM, Garau C, Alachkar A, Wang L, Wang Z, Nishimori K, Xu X, Civelli O. Melanin concentrating hormone modulates oxytocin-mediated marble burying. Neuropharmacology 2018; 128:22-32. [PMID: 28888943 PMCID: PMC5830107 DOI: 10.1016/j.neuropharm.2017.09.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 08/15/2017] [Accepted: 09/05/2017] [Indexed: 11/27/2022]
Abstract
Repetitive and perseverative behaviors are common features of a number of neuropsychiatric diseases such as Angelman's syndrome, Tourette's syndrome, obsessive-compulsive disorder, and autism spectrum disorders. The oxytocin system has been linked to the regulation of repetitive behavior in both animal models and humans, but many of its downstream targets have still to be found. We report that the melanin-concentrating hormone (MCH) system is a target of the oxytocin system in regulating one repetitive behavior, marble burying. First we report that nearly 60% of MCH neurons express oxytocin receptors, and demonstrate using rabies mediated tract tracing that MCH neurons receive direct presynaptic input from oxytocin neurons. Then we show that MCH receptor knockout (MCHR1KO) mice and MCH ablated animals display increased marble burying response while central MCH infusion decreases it. Finally, we demonstrate the downstream role of the MCH system on oxytocin mediated marble burying by showing that central infusions of MCH and oxytocin alone or together reduce it while antagonizing the MCH system blocks oxytocin-mediated reduction of this behavior. Our findings reveal a novel role for the MCH system as a mediator of the role of oxytocin in regulating marble-burying behavior in mice.
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Affiliation(s)
- Nayna M Sanathara
- Department of Pharmacology, University of California, Irvine, CA, 92697, USA
| | - Celia Garau
- Department of Pharmaceutical Sciences, University of California, Irvine, CA, 92697, USA
| | - Amal Alachkar
- Department of Pharmacology, University of California, Irvine, CA, 92697, USA
| | - Lien Wang
- Department of Pharmacology, University of California, Irvine, CA, 92697, USA
| | - Zhiwei Wang
- Department of Pharmacology, University of California, Irvine, CA, 92697, USA
| | - Katsuhiko Nishimori
- Department of Molecular and Cell Biology, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai, Miyagi, 981-8555, Japan
| | - Xiangmin Xu
- Department of Anatomy and Neurobiology, University of California, Irvine, CA, 92697, USA
| | - Olivier Civelli
- Department of Pharmacology, University of California, Irvine, CA, 92697, USA; Department of Pharmaceutical Sciences, University of California, Irvine, CA, 92697, USA; Department of Developmental and Cell Biology, University of California, Irvine, CA, 92697, USA.
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7
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Kobayashi Y, Kulikova SP, Shibato J, Rakwal R, Satoh H, Pinault D, Masuo Y. DNA microarray unravels rapid changes in transcriptome of MK-801 treated rat brain. World J Biol Chem 2015; 6:389-408. [PMID: 26629322 PMCID: PMC4657125 DOI: 10.4331/wjbc.v6.i4.389] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 01/20/2015] [Accepted: 08/31/2015] [Indexed: 02/05/2023] Open
Abstract
AIM: To investigate the impact of MK-801 on gene expression patterns genome wide in rat brain regions.
METHODS: Rats were treated with an intraperitoneal injection of MK-801 [0.08 (low-dose) and 0.16 (high-dose) mg/kg] or NaCl (vehicle control). In a first series of experiment, the frontoparietal electrocorticogram was recorded 15 min before and 60 min after injection. In a second series of experiments, the whole brain of each animal was rapidly removed at 40 min post-injection, and different regions were separated: amygdala, cerebral cortex, hippocampus, hypothalamus, midbrain and ventral striatum on ice followed by DNA microarray (4 × 44 K whole rat genome chip) analysis.
RESULTS: Spectral analysis revealed that a single systemic injection of MK-801 significantly and selectively augmented the power of baseline gamma frequency (30-80 Hz) oscillations in the frontoparietal electroencephalogram. DNA microarray analysis showed the largest number (up- and down- regulations) of gene expressions in the cerebral cortex (378), midbrain (376), hippocampus (375), ventral striatum (353), amygdala (301), and hypothalamus (201) under low-dose (0.08 mg/kg) of MK-801. Under high-dose (0.16 mg/kg), ventral striatum (811) showed the largest number of gene expression changes. Gene expression changes were functionally categorized to reveal expression of genes and function varies with each brain region.
CONCLUSION: Acute MK-801 treatment increases synchrony of baseline gamma oscillations, and causes very early changes in gene expressions in six individual rat brain regions, a first report.
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The neuroanatomical function of leptin in the hypothalamus. J Chem Neuroanat 2014; 61-62:207-20. [PMID: 25007719 DOI: 10.1016/j.jchemneu.2014.05.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Revised: 05/09/2014] [Accepted: 05/28/2014] [Indexed: 02/07/2023]
Abstract
The anorexigenic hormone leptin plays an important role in the control of food intake and feeding-related behavior, for an important part through its action in the hypothalamus. The adipose-derived hormone modulates a complex network of several intercommunicating orexigenic and anorexigenic neuropeptides in the hypothalamus to reduce food intake and increase energy expenditure. In this review we present an updated overview of the functional role of leptin in respect to feeding and feeding-related behavior per distinct hypothalamic nuclei. In addition to the arcuate nucleus, which is a major leptin sensitive hub, leptin-responsive neurons in other hypothalamic nuclei, including the, dorsomedial-, ventromedial- and paraventricular nucleus and the lateral hypothalamic area, are direct targets of leptin. However, leptin also modulates hypothalamic neurons in an indirect manner, such as via the melanocortin system. The dissection of the complexity of leptin's action on the networks involved in energy balance is subject of recent and future studies. A full understanding of the role of hypothalamic leptin in the regulation of energy balance requires cell-specific manipulation using of conditional deletion and expression of leptin receptors. In addition, optogenetic and pharmacogenetic tools in combination with other pharmacological (such as the recent discovery of a leptin receptor antagonist) and neuronal tracing techniques to map the circuit, will be helpful to understand the role of leptin receptor expressing neurons. Better understanding of these circuits and the involvement of leptin could provide potential sites for therapeutic interventions in obesity and metabolic diseases characterized by dysregulation of energy balance.
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Pérez-Sieira S, López M, Nogueiras R, Tovar S. Regulation of NR4A by nutritional status, gender, postnatal development and hormonal deficiency. Sci Rep 2014; 4:4264. [PMID: 24584059 PMCID: PMC3939456 DOI: 10.1038/srep04264] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 02/14/2014] [Indexed: 01/11/2023] Open
Abstract
The NR4A is a subfamily of the orphan nuclear receptors (NR) superfamily constituted by three well characterized members: Nur77 (NR4A1), Nurr1 (NR4A2) and Nor 1 (NR4A3). They are implicated in numerous biological processes as DNA repair, arteriosclerosis, cell apoptosis, carcinogenesis and metabolism. Several studies have demonstrated the role of this subfamily on glucose metabolism, insulin sensitivity and energy balance. These studies have focused mainly in liver and skeletal muscle. However, its potential role in white adipose tissue (WAT), one of the most important tissues involved in the regulation of energy homeostasis, is not well-studied. The aim of this work was to elucidate the regulation of NR4A in WAT under different physiological and pathophysiological settings involved in energy balance such as fasting, postnatal development, gender, hormonal deficiency and pregnancy. We compared NR4A mRNA expression of Nur77, Nurr1 and Nor 1 and found a clear regulation by nutritional status, since the expression of the 3 isoforms is increased after fasting in a leptin-independent manner and sex steroid hormones also modulate NR4A expression in males and females. Our findings indicate that NR4A are regulated by different physiological and pathophysiological settings known to be associated with marked alterations in glucose metabolism and energy status.
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Affiliation(s)
- S Pérez-Sieira
- 1] Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, 15782, Spain [2] CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), 15706, Spain
| | - M López
- 1] Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, 15782, Spain [2] CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), 15706, Spain
| | - R Nogueiras
- 1] Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, 15782, Spain [2] CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), 15706, Spain
| | - S Tovar
- 1] Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, 15782, Spain [2] CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), 15706, Spain
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10
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Imbernon M, Beiroa D, Vázquez MJ, Morgan DA, Veyrat–Durebex C, Porteiro B, Díaz–Arteaga A, Senra A, Busquets S, Velásquez DA, Al–Massadi O, Varela L, Gándara M, López–Soriano F, Gallego R, Seoane LM, Argiles JM, López M, Davis RJ, Sabio G, Rohner–Jeanrenaud F, Rahmouni K, Dieguez C, Nogueiras R. Central melanin-concentrating hormone influences liver and adipose metabolism via specific hypothalamic nuclei and efferent autonomic/JNK1 pathways. Gastroenterology 2013; 144:636-649.e6. [PMID: 23142626 PMCID: PMC3663042 DOI: 10.1053/j.gastro.2012.10.051] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 10/10/2012] [Accepted: 10/31/2012] [Indexed: 01/18/2023]
Abstract
BACKGROUND & AIMS Specific neuronal circuits modulate autonomic outflow to liver and white adipose tissue. Melanin-concentrating hormone (MCH)-deficient mice are hypophagic, lean, and do not develop hepatosteatosis when fed a high-fat diet. Herein, we sought to investigate the role of MCH, an orexigenic neuropeptide specifically expressed in the lateral hypothalamic area, on hepatic and adipocyte metabolism. METHODS Chronic central administration of MCH and adenoviral vectors increasing MCH signaling were performed in rats and mice. Vagal denervation was performed to assess its effect on liver metabolism. The peripheral effects on lipid metabolism were assessed by real-time polymerase chain reaction and Western blot. RESULTS We showed that the activation of MCH receptors promotes nonalcoholic fatty liver disease through the parasympathetic nervous system, whereas it increases fat deposition in white adipose tissue via the suppression of sympathetic traffic. These metabolic actions are independent of parallel changes in food intake and energy expenditure. In the liver, MCH triggers lipid accumulation and lipid uptake, with c-Jun N-terminal kinase being an essential player, whereas in adipocytes MCH induces metabolic pathways that promote lipid storage and decreases lipid mobilization. Genetic activation of MCH receptors or infusion of MCH specifically in the lateral hypothalamic area modulated hepatic lipid metabolism, whereas the specific activation of this receptor in the arcuate nucleus affected adipocyte metabolism. CONCLUSIONS Our findings show that central MCH directly controls hepatic and adipocyte metabolism through different pathways.
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Affiliation(s)
- Monica Imbernon
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain,Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Daniel Beiroa
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain,Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - María J. Vázquez
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain,Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Donald A. Morgan
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Christelle Veyrat–Durebex
- Laboratory of Metabolism, Division of Endocrinology, Diabetology and Nutrition, Department of Internal Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Begoña Porteiro
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain,Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Adenis Díaz–Arteaga
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain,Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Ana Senra
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain,Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Silvia Busquets
- Department of Biochemistry and Molecular Biology, University of Barcelona, Barcelona, Spain
| | - Douglas A. Velásquez
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain,Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Omar Al–Massadi
- Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain,Grupo Fisiopatología Endocrina, Complejo Hospitalario Universitario de Santiago-Instituto de Investigación Sanitaria (IDIS/SERGAS) Santiago de Compostela, Spain
| | - Luis Varela
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain,Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Marina Gándara
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain
| | | | - Rosalía Gallego
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain
| | - Luisa M. Seoane
- Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain,Grupo Fisiopatología Endocrina, Complejo Hospitalario Universitario de Santiago-Instituto de Investigación Sanitaria (IDIS/SERGAS) Santiago de Compostela, Spain
| | - Josep M. Argiles
- Department of Biochemistry and Molecular Biology, University of Barcelona, Barcelona, Spain
| | - Miguel López
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain,Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Roger J. Davis
- Howard Hughes Medical Institute, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Guadalupe Sabio
- Department of Vascular Biology and Inflammation, Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, Spain
| | - Françoise Rohner–Jeanrenaud
- Laboratory of Metabolism, Division of Endocrinology, Diabetology and Nutrition, Department of Internal Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Kamal Rahmouni
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Carlos Dieguez
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain,Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - Ruben Nogueiras
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), Spain,Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
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11
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Barson JR, Morganstern I, Leibowitz SF. Complementary roles of orexin and melanin-concentrating hormone in feeding behavior. Int J Endocrinol 2013; 2013:983964. [PMID: 23935621 PMCID: PMC3727095 DOI: 10.1155/2013/983964] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 06/21/2013] [Indexed: 11/18/2022] Open
Abstract
Transcribed within the lateral hypothalamus, the neuropeptides orexin/hypocretin (OX) and melanin-concentrating hormone (MCH) both promote palatable food intake and are stimulated by palatable food. While these two neuropeptides share this similar positive relationship with food, recent evidence suggests that this occurs through different albeit complementary effects on behavior, with OX promoting food seeking and motivation for palatable food and MCH functioning during ongoing food intake, reinforcing the consumption of calorically dense foods. Further differences are evident in their effects on physiological processes, which are largely opposite in nature. For example, activation of OX receptors, which is neuronally excitatory, promotes waking, increases energy expenditure, and enhances limbic dopamine levels and reward. In contrast, activation of MCH receptors, which is neuronally inhibitory, promotes paradoxical sleep, enhances energy conservation, reduces limbic dopamine, and increases depressive behavior. This review describes these different effects of the neuropeptides, developing the hypothesis that they stimulate the consumption of palatable food through excessive seeking in the case of OX and through excessive energy conservation in the case of MCH. It proposes that OX initiates food intake and subsequently stimulates MCH which then acts to prolong the consumption of palatable, energy-dense food.
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Affiliation(s)
- Jessica R. Barson
- Laboratory of Behavioral Neurobiology, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Irene Morganstern
- Laboratory of Behavioral Neurobiology, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Sarah F. Leibowitz
- Laboratory of Behavioral Neurobiology, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
- *Sarah F. Leibowitz:
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12
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Nocjar C, Zhang J, Feng P, Panksepp J. The social defeat animal model of depression shows diminished levels of orexin in mesocortical regions of the dopamine system, and of dynorphin and orexin in the hypothalamus. Neuroscience 2012; 218:138-53. [DOI: 10.1016/j.neuroscience.2012.05.033] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 05/11/2012] [Accepted: 05/11/2012] [Indexed: 01/13/2023]
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13
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Chen H, Iglesias MA, Caruso V, Morris MJ. Maternal cigarette smoke exposure contributes to glucose intolerance and decreased brain insulin action in mice offspring independent of maternal diet. PLoS One 2011; 6:e27260. [PMID: 22076142 PMCID: PMC3208635 DOI: 10.1371/journal.pone.0027260] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2011] [Accepted: 10/12/2011] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Maternal smoking leads to intrauterine undernutrition and is associated with low birthweight and higher risk of offspring obesity. Intrauterine smoke exposure (SE) may alter neuroendocrine mediators regulating energy homeostasis as chemicals in cigarette smoke can reach the fetus. Maternal high-fat diet (HFD) consumption causes fetal overnutrition; however, combined effects of HFD and SE are unknown. Thus we investigated the impact of combined maternal HFD and SE on adiposity and energy metabolism in offspring. METHOD Female Balb/c mice had SE (2 cigarettes/day, 5 days/week) or were sham exposed for 5 weeks before mating. Half of each group was fed HFD (33% fat) versus chow as control. The same treatment continued throughout gestation and lactation. Female offspring were fed chow after weaning and sacrificed at 12 weeks. RESULTS Birthweights were similar across maternal groups. Faster growth was evident in pups from SE and/or HFD dams before weaning. At 12 weeks, offspring from HFD-fed dams were significantly heavier than those from chow-fed dams (chow-sham 17.6±0.3 g; chow-SE 17.8±0.2 g; HFD-sham 18.7±0.3 g; HFD-SE 18.8±0.4 g, P<0.05 maternal diet effect); fat mass was significantly greater in offspring from chow+SE, HFD+SE and HFD+sham dams. Both maternal HFD and SE affected brain lactate transport. Glucose intolerance and impaired brain response to insulin were observed in SE offspring, and this was aggravated by maternal HFD consumption. CONCLUSION While maternal HFD led to increased body weight in offspring, maternal SE independently programmed adverse health outcomes in offspring. A smoke free environment and healthy diet during pregnancy is desirable to optimize offspring health.
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Affiliation(s)
- Hui Chen
- School of Medical and Molecular Bioscience, Faculty of Science, University of Technology, Sydney, Sydney, New South Wales, Australia.
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14
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Toshinai K, Yamaguchi H, Kageyama H, Matsuo T, Koshinaka K, Sasaki K, Shioda S, Minamino N, Nakazato M. Neuroendocrine regulatory peptide-2 regulates feeding behavior via the orexin system in the hypothalamus. Am J Physiol Endocrinol Metab 2010; 299:E394-401. [PMID: 20551287 DOI: 10.1152/ajpendo.00768.2009] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Neuroendocrine regulatory peptide (NERP)-1 and NERP-2 are derived from distinct regions of VGF, a neurosecretory protein. Vgf(-/-) mice exhibit dwarfism and hypermetabolic rates, suggesting that VGF or VGF-derived peptides play important roles in energy metabolism. Here, we examined the role of NERPs in the central regulation of feeding and energy homeostasis. We attempted to identify NERPs expressing neurons in rats by immunohistochemistry. We studied the effects of intracerebroventricular (icv) administration of NERP-2 on feeding, body temperature, oxygen consumption, and locomotor activity in rats and mice. Intracerebroventricular administration of NERP-2, but not NERP-1 or a form of NERP-2 bearing a COOH-terminal glycine extension, increased food intake in rats. We investigated the downstream signal of NERP-2 on the basis of studies of NERP-2-induced feeding with neutralization of orexins, neuropeptide Y, or agouti-related protein. NERP-2 expression localized to the lateral hypothalamus (LH) and the dorsomedial perifornical hypothalamus in rats, colocalizing with orexins that activate feeding behavior and arousal. NERP-2 administration induced Fos protein, a marker of neuronal activation, in the orexin-immunoreactive neurons. Vgf mRNA levels were upregulated in the rat LH upon food deprivation. Intracerebroventricular administration of NERP-2 also increased body temperature, oxygen consumption, and locomotor activity in rats. Treatment with anti-NERP-2 IgG decreased food intake. NERP-2-induced bioactivities could be abrogated by administration of anti-orexins IgG or orexin receptor antagonists. NERP-2 did not induce food intake or locomotor activity in orexin-deficient mice. Our findings indicate that hypothalamic NERP-2 plays a role in the control of food intake and energy homeostasis via the orexin pathway. Thus, VGF serves as a precursor of multiple bioactive peptides exerting a diverse set of neuroendocrine functions.
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15
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Matsuda K, Kojima K, Shimakura SI, Miura T, Uchiyama M, Shioda S, Ando H, Takahashi A. Relationship between melanin-concentrating hormone- and neuropeptide Y-containing neurons in the goldfish hypothalamus. Comp Biochem Physiol A Mol Integr Physiol 2009; 153:3-7. [DOI: 10.1016/j.cbpa.2008.10.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2008] [Revised: 09/30/2008] [Accepted: 10/02/2008] [Indexed: 10/21/2022]
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16
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Chen H, Simar D, Lambert K, Mercier J, Morris MJ. Maternal and postnatal overnutrition differentially impact appetite regulators and fuel metabolism. Endocrinology 2008; 149:5348-56. [PMID: 18635655 DOI: 10.1210/en.2008-0582] [Citation(s) in RCA: 185] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Maternal obesity is increasing, and it is known that the intrauterine experience programs fetal and newborn metabolism. However, the relative contributions of pre- or postnatal factors are unknown. We hypothesized that maternal overnutrition caused by long-term maternal obesity would exert a stronger detrimental impact than postnatal overnutrition on offspring metabolic homeostasis, with additional postnatal overnutrition exaggerating these alterations. Female Sprague Dawley rats were exposed to chow or high-fat cafeteria diet for 5 wk before mating and throughout gestation and lactation. On postnatal d 1, litters were adjusted to three per litter to induce postnatal overnutrition (vs. 12 in control). Hypothalamic appetite regulators neuropeptide Y and proopiomelanocortin, glucose transporter 4, and lipid metabolic markers were measured. At postnatal d 20, male pups born of obese dams, or those overnourished postnatally, were 42% heavier than controls; combining both interventions led to 80% greater body weight. Maternal obesity increased pup adiposity and led to glucose intolerance in offspring; these were exaggerated by additional postnatal overnutrition during lactation. Maternal obesity was also linked to hyperlipidemia in offspring and reduced hypothalamic neuropeptide Y and increased proopiomelanocortin mRNA expression. Postnatal overnutrition of offspring from obese dams amplified these hypothalamic changes. Both maternal and postnatal overnutrition reduced muscle glucose transporter 4. Adipose carnitine palmitoyl-transferase-1 and adipose triglyceride lipase mRNA was up-regulated only by postnatal overnutrition. Maternal overnutrition appears to alter central appetite circuits and promotes early-onset obesity; postnatal overnutrition interacted to cause peripheral lipid and glucose metabolic disorders, supporting the critical message to reduce early-life adverse nutritional impact.
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Affiliation(s)
- Hui Chen
- Department of Pharmacology, School of Medical Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
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17
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Gomori A, Ishihara A, Ito M, Matsushita H, Ito M, Mashiko S, Iwaasa H, Matsuda M, Bednarek MA, Qian S, MacNeil DJ, Kanatani A. Blockade of MCH1 receptor signalling ameliorates obesity and related hepatic steatosis in ovariectomized mice. Br J Pharmacol 2007; 151:900-8. [PMID: 17519948 PMCID: PMC2014135 DOI: 10.1038/sj.bjp.0707292] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND AND PURPOSE Melanin-concentrating hormone (MCH) is a cyclic orexigenic neuropeptide predominantly expressed in the lateral hypothalamus. We investigated the roles of MCH1 receptor signalling in ovariectomy (OVX)-induced obesity in female C57BL/6J mice, an animal model of postmenopausal obesity. EXPERIMENTAL APPROACH The effects of blocking signalling via the MCH1 receptor on OVX-induced obesity was investigated by using Mch1r deficient (KO) mice and chronic treatment with a selective MCH1 receptor antagonist. KEY RESULTS OVX induced body weight gain and increases in the weight of visceral fat and of liver; these effects were attenuated following OVX in Mch1r KO mice. OVX-induced triglyceride (TG) accumulation and elevated expression of lipogenic genes were significantly ameliorated in the liver of Mch1r KO mice. In agreement with these results, chronic i.c.v. infusion of a selective MCH1 receptor antagonist significantly reduced body weight gain, visceral fat and liver weights in OVX mice, and hepatic TG contents and lipogenic gene expression levels were normalized. CONCLUSION AND IMPLICATIONS Our results indicate that MCH1 receptor signalling is involved in the development of fatty liver, as well as obesity, in OVX mice, and suggest a therapeutic potential for MCH1 receptor antagonists in the treatment of obesity and fatty liver.
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Affiliation(s)
- A Gomori
- Department of Pharmacology, Tsukuba Research Institute, Banyu Pharmaceutical Co. Ltd Tsukuba, Japan
| | - A Ishihara
- Department of Pharmacology, Tsukuba Research Institute, Banyu Pharmaceutical Co. Ltd Tsukuba, Japan
- Author for correspondence:
| | - M Ito
- Department of Metabolic Disorder Research, Tsukuba Research Institute, Banyu Pharmaceutical Co. Ltd Tsukuba, Japan
| | - H Matsushita
- Department of Pharmacology, Tsukuba Research Institute, Banyu Pharmaceutical Co. Ltd Tsukuba, Japan
| | - M Ito
- Department of Metabolic Disorder Research, Tsukuba Research Institute, Banyu Pharmaceutical Co. Ltd Tsukuba, Japan
| | - S Mashiko
- Department of Pharmacology, Tsukuba Research Institute, Banyu Pharmaceutical Co. Ltd Tsukuba, Japan
| | - H Iwaasa
- Department of Metabolic Disorder Research, Tsukuba Research Institute, Banyu Pharmaceutical Co. Ltd Tsukuba, Japan
| | - M Matsuda
- Department of Chemistry, Tsukuba Research Institute, Banyu Pharmaceutical Co. Ltd Tsukuba, Japan
| | - M A Bednarek
- Department of Medicinal Chemistry, Merck Research Laboratories Rahway, NJ, USA
| | - S Qian
- Department of Metabolic Disorders, Merck Research Laboratories Rahway, NJ, USA
| | - D J MacNeil
- Department of Metabolic Disorders, Merck Research Laboratories Rahway, NJ, USA
| | - A Kanatani
- Department of Metabolic Disorder Research, Tsukuba Research Institute, Banyu Pharmaceutical Co. Ltd Tsukuba, Japan
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Morris MJ, Gannan E, Stroud LM, Beck-Sickinger AG, O'Brien TJ. Neuropeptide Y suppresses absence seizures in a genetic rat model primarily through effects on Y2 receptors. Eur J Neurosci 2007; 25:1136-43. [PMID: 17331209 DOI: 10.1111/j.1460-9568.2007.05348.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Neuropeptide Y (NPY) potently suppresses absence seizures in a model of genetic generalized epilepsy, genetic absence epilepsy rats of Strasbourg (GAERS). Here we investigated the Y-receptor subtype(s) on which NPY exerts this anti-absence effect. A dual in vivo approach was used: the cumulative duration of seizures was quantified in adult male GAERS in 90-min electroencephalogram recordings following intracerebroventricular (i.c.v.) injection of: (i) subtype-selective agonists of Y1 ([Leu31Pro34]NPY, 2.5 nmol), Y2 (Ac[Leu(28,31)]NPY24-36, 3 nmol), Y5 receptors [hPP1(-17),Ala31,Aib32]NPY, 4 nmol), NPY (3 nmol) or vehicle; and following (ii) i.c.v. injection of antagonists of Y1 (BIBP3226, 20 nmol), Y2 (BIIE0246, 20 nmol) and Y5 (NPY5RA972, 20 nmol) receptors or vehicle, followed by NPY (3 nmol). Injection of the Y1- and Y5-selective agonists resulted in significantly less mean seizure suppression (37.4% and 53.9%, respectively) than NPY (83.2%; P < 0.05), while the Y2 agonist had similar effects to NPY (62.3% suppression, P = 0.57). Food intake was not increased following injection of the Y2 agonist, while significant increases in food intake were seen following NPY and the other Y-subtype agonists. Compared with vehicle, NPY injection suppressed seizures following the Y1 and Y5 antagonists (45.3% and 80.1%, respectively, P < 0.05), but not following the Y2 antagonist (5.1% suppression, P = 0.46). We conclude that NPY Y2 receptors are more important than Y1 and Y5 receptors in mediating the effect of NPY to suppress absence seizures in a genetic rat model. Y2 receptor agonists may represent targets for novel drugs against genetic generalized epilepsies without resulting in appetite stimulation.
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Affiliation(s)
- Margaret J Morris
- Department of Physiology and Pharmacology, University of New South Wales, Kensington, New South Wales, Australia, 2052.
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Tavares FX, Al-Barazanji KA, Bigham EC, Bishop MJ, Britt CS, Carlton DL, Feldman PL, Goetz AS, Grizzle MK, Guo YC, Handlon AL, Hertzog DL, Ignar DM, Lang DG, Ott RJ, Peat AJ, Zhou HQ. Potent, Selective, and Orally Efficacious Antagonists of Melanin-Concentrating Hormone Receptor 1. J Med Chem 2006; 49:7095-107. [PMID: 17125262 DOI: 10.1021/jm060572f] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The high expression of MCH in the hypothalamus with the lean hypophagic phenotype coupled with increased resting metabolic rate and resistance to high fat diet-induced obesity of MCH KO mice has spurred considerable efforts to develop small molecule MCHR1 antagonists. Starting from a lead thienopyrimidinone series, structure-activity studies at the 3- and 6-positions of the thienopyrimidinone core afforded potent and selective MCHR1 antagonists with representative examples having suitable pharmacokinetic properties. Based on structure-activity relationships, a structural model for MCHR1 was constructed to explain the binding mode of these antagonists. In general, a good correlation was observed between pKas and activity in the right-hand side of the template, with Asp123 playing an important role in the enhancement of binding affinity. A representative example when evaluated chronically in diet-induced obese mice resulted in good weight loss effects. These antagonists provide a viable lead series in the discovery of new therapies for the treatment of obesity.
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Affiliation(s)
- Francis X Tavares
- Department of Medicinal Chemistry, GlaxoSmithKline, Research Triangle Park, North Carolina 27709, USA.
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Jobst EE, Enriori PJ, Sinnayah P, Cowley MA. Hypothalamic regulatory pathways and potential obesity treatment targets. Endocrine 2006; 29:33-48. [PMID: 16622291 DOI: 10.1385/endo:29:1:33] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2005] [Revised: 11/30/1999] [Accepted: 11/08/2005] [Indexed: 12/25/2022]
Abstract
With an ever-growing population of obese people as well as comorbidities associated with obesity, finding effective weight loss strategies is more imperative than ever. One of the challenges in curbing the obesity crisis is designing successful strategies for long-term weight loss and weight-loss maintenance. Currently, weight-loss strategies include promotion of therapeutic lifestyle changes (diet and exercise), pharmacological therapy, and bariatric surgery. This review focuses on several pharmacological targets that activate central nervous system pathways that normally limit food intake and body weight. Though it is likely that no single therapy will prove effective for everyone, this review considers several recent pre-clinical targets, and several compounds that have been in human clinical trials.
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Affiliation(s)
- Erin E Jobst
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA.
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Kobashi M, Shimatani Y, Shirota K, Xuan SY, Mitoh Y, Matsuo R. Central neuropeptide Y induces proximal stomach relaxation via Y1 receptors in the dorsal vagal complex of the rat. Am J Physiol Regul Integr Comp Physiol 2005; 290:R290-7. [PMID: 16195495 DOI: 10.1152/ajpregu.00423.2005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Effects of neuropeptide Y (NPY) on motility of the proximal stomach was examined in anesthetized rats. Intragastric pressure was measured using a balloon situated in the proximal part of the stomach. Administration of NPY into the fourth ventricle induced relaxation of the proximal stomach in a dose-dependent manner. Administration of an Y1 receptor (Y1R) agonist [Leu31, Pro34]NPY induced a larger relaxation than NPY. The administration of an Y2 receptor agonist (NPY 13-36) did not induce significant changes in motility. Microinjections of [Leu31, Pro34]NPY into the caudal part of the dorsal vagal complex (DVC) induced relaxation of the proximal stomach. In contrast, similar injections into the intermediate part of the DVC increased IGP of the proximal stomach. Administration of NPY into the fourth ventricle did not induce relaxation after bilateral injections of the Y1R antagonist (1229U91) into the caudal DVC. These results indicate that NPY induces relaxation in the proximal stomach via Y1Rs situated in the DVC. Because bilateral vagotomy below the diaphragm abolished the relaxation induced by the administration of NPY into the fourth ventricle, relaxation induced by NPY is probably mediated by vagal preganglionic neurons. Intravenous injection of atropine methyl nitrate reduced relaxation induced by administration of NPY. Therefore, relaxation induced by NPY is likely mediated by peripheral cholinergic neurons.
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Affiliation(s)
- Motoi Kobashi
- Department of Oral Physiology, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8525, Japan.
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Faulconbridge LF, Grill HJ, Kaplan JM. Distinct forebrain and caudal brainstem contributions to the neuropeptide Y mediation of ghrelin hyperphagia. Diabetes 2005; 54:1985-93. [PMID: 15983198 DOI: 10.2337/diabetes.54.7.1985] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Neuropeptide Y (NPY) has been implicated in the downstream mediation of ghrelin hyperphagia, with the site of action for both peptides considered to be intrinsic to the hypothalamus. Here, however, we observed robust hyperphagia with caudal brainstem (CBS) (fourth intracerebroventricular) ghrelin delivery and, moreover, that this response was reversed with coadministration of either of two NPY receptor antagonists (1229U91 and D-Tyr27,36, D-Thr32 NPY27-36) with contrasting NPY receptor subtype-binding properties. The same results were obtained after forebrain (third intracerebroventricular) administration, but the sites for both ghrelin and antagonist action were open to question, given the caudal flow of cerebrospinal fluid (CSF) through the ventricular system. To control for this, we occluded the cerebral aqueduct to restrict CSF flow between the forebrain and CBS ventricles and tested all combinations (same and cross ventricle) of ghrelin (150 pmol/1 microl) and NPY receptor antagonist delivery. With fourth intracerebroventricular ghrelin delivery after aqueduct occlusion, preadministration of either of the two antagonists through the same cannula reversed the hyperphagic response but neither was effective when delivered to the third ventricle. With third intracerebroventricular ghrelin administration, however, 1229U91 reversed the ingestive response only when delivered to the fourth ventricle, whereas D-Tyr27,36) D-Thr32 NPY27-36 was effective only when delivered to the forebrain. These results demonstrate distinct mediating pathways (due to location and subtypes of relevant NPY receptor) for the hyperphagic response driven separately by forebrain and CBS ghrelin administration.
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Affiliation(s)
- Lucy F Faulconbridge
- Department of Psychology, University of Pennsylvania, 3720 Walnut St., Philadelphia, PA 19104, USA.
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Williamson-Hughes PS, Grove KL, Smith MS. Melanin concentrating hormone (MCH): A novel neural pathway for regulation of GnRH neurons. Brain Res 2005; 1041:117-24. [PMID: 15829220 DOI: 10.1016/j.brainres.2004.11.066] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2004] [Revised: 11/01/2004] [Accepted: 11/06/2004] [Indexed: 11/23/2022]
Abstract
The link between the state of energy balance and reproductive function is well known. Thus, signals denoting negative energy balance and the accompanying hyperphagic drive are likely to be factors in the suppression of gonadotropin releasing hormone (GnRH) activity. We have previously found that appetite-regulating systems, such as neuropeptide Y (NPY) in the arcuate nucleus (ARH) and orexin in the lateral hypothalamic area (LHA), send fiber projections that come in close apposition with GnRH neurons. Furthermore, the appropriate receptors, NPY Y5 and OR-1, respectively, are coexpressed on GnRH neurons, providing neuroanatomical evidence for a direct link between the NPY and orexin systems and GnRH neurons. Therefore, these orexigenic neuropeptide systems are potential candidates that convey information about energy balance to GnRH neurons. The current studies focused on melanin concentrating hormone (MCH), another orexigenic neuropeptide system located in the LHA that is sensitive to energy balance. The results showed that MCH fiber projections came in close apposition with approximately 85-90% of GnRH cell bodies throughout the preoptic area and anterior hypothalamic area in the rat. In addition, the MCH receptor (MCHR1) was coexpressed on about 50-55% of GnRH neurons. These findings present evidence for a possible direct neuroanatomical pathway by which MCH may play a role in the regulation of GnRH neuronal function. Thus, MCH is another potential signal that may serve to integrate energy balance and reproductive function.
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Affiliation(s)
- Patricia S Williamson-Hughes
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006, USA
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Kalra SP, Kalra PS. Neuropeptide Y: a physiological orexigen modulated by the feedback action of ghrelin and leptin. Endocrine 2003; 22:49-56. [PMID: 14610298 DOI: 10.1385/endo:22:1:49] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2003] [Accepted: 04/14/2003] [Indexed: 01/16/2023]
Abstract
Neuropeptide Y (NPY), a 36-amino-acid neuropeptide is the most potent physiological appetite transducer known. Episodic NPY neurosecretion in hypothalamic target sites is temporally linked with onset of the daily feeding pattern. Upregulation of NPY signaling in the arcuate nucleus-paraventricular nucleus (ARC-PVN) neural axis is responsible for the hyperphagia evoked by dieting, fasting, hormonal and genetic factors, and disruption in intrahypothalamic signaling. Clusters of NPY-producing neurons in the ARC that coexpress gamma- amino butyric acid and agouti-related peptide, and those in the brain stem (BS) that coexpress catecholamines and galanin, participate in disparate manners to regulate appetitive behavior. NPY receptors, Y1, Y2, and Y5, expressed by various components of the NPY network, mediate NPY-induced feeding. Imbalance in NPY signaling due either to high or low abundance of NPY at target sites elicits hyperphagia leading to increased fat accretion and obesity. Recent studies show that intermittent, feedback action of opposing afferent hormonal signals-leptin from adipose tissue and ghrelin from stomach-regulate the episodic secretion of orexigenic NPY in the PVN-ARC. Apparently, the hypothalamic NPY network is the primary common pathway intimately involved in genesis of appetite- stimulating impulses.
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Affiliation(s)
- Satya P Kalra
- Department of Neuroscience, McKnight Brain Institute, PO Box 100244, University of Florida, Gainesville, FL 32610-0244, USA.
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Abstract
Endocannabinoids, endogenous ligands of cannabinoid receptor type 1 (CB1), have emerged as novel and important regulators of energy homeostasis. A report in this issue demonstrates reduced body weight, fat mass, and appetite in CB1-/- mice. Examination of the underlying mechanisms reveals a dual role for endocannabinoids as they affect both appetite and peripheral lipolysis.
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Affiliation(s)
- Tamas L Horvath
- Department of Obstetrics and Gynecology, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
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O'Shea M, Hansen MJ, Tatemoto K, Morris MJ. Inhibitory effect of apelin-12 on nocturnal food intake in the rat. Nutr Neurosci 2003; 6:163-7. [PMID: 12793520 DOI: 10.1080/1028415031000111273] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Apelin, the endogenous peptide ligand of the APJ receptor, is expressed in brain regions implicated in food and water intake. This study reports for the first time, the effect of apelin-12, one of the most potent apelin peptides, on spontaneous (nocturnal) feeding. Randomised intracerebroventricular injection of 1, 3 and 10 nmol apelin-12 or saline vehicle, 10 min prior to lights out, led to dose-dependent reductions in food intake 2-4 h after injection (n = 7; p < 0.05). This suggests that apelin-12 exerts a delayed inhibitory effect on nocturnal feeding. Relative to saline, no effect was observed on total 24-h food intake post injection. In contrast, day-time administration of 10 nmol apelin-12 to satiated rats stimulated feeding (n = 5-11; p < 0.05); lower doses had no effect. No changes in water intake were observed after apelin-12. These results suggest that apelin is involved in the central control of feeding.
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Affiliation(s)
- Marie O'Shea
- Department of Pharmacology, Centre for Neuroscience, The University of Melbourne, Victoria 3010, Australia
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Berglund MM, Hipskind PA, Gehlert DR. Recent developments in our understanding of the physiological role of PP-fold peptide receptor subtypes. Exp Biol Med (Maywood) 2003; 228:217-44. [PMID: 12626767 DOI: 10.1177/153537020322800301] [Citation(s) in RCA: 169] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The three peptides pancreatic polypeptide (PP), peptide YY (PYY), and neuropeptide Y (NPY) share a similar structure known as the PP-fold. There are four known human G-protein coupled receptors for the PP-fold peptides, namely Y1, Y2, Y4, and Y5, each of them being able to bind at least two of the three endogenous ligands. All three peptides are found in the circulation acting as hormones. Although NPY is only released from neurons, PYY and PP are primarily found in endocrine cells in the gut, where they exert such effects as inhibition of gall bladder secretion, gut motility, and pancreatic secretion. However, when PYY is administered in an experimental setting to animals, cloned receptors, or tissue preparations, it can mimic the effects of NPY in essentially all studies, making it difficult to study the effects of PP-fold peptides and to delineate what receptor and peptide accounts for a particular effect. Initial studies with transgenic animals confirmed the well-established action of NPY on metabolism, food-intake, vascular systems, memory, mood, neuronal excitability, and reproduction. More recently, using transgenic techniques and novel antagonists for the Y1, Y2, and Y5 receptors, NPY has been found to be a key player in the regulation of ethanol consumption and neuronal development.
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Affiliation(s)
- Magnus M Berglund
- Eli Lilly and Company, Lilly Research Laboratories, Indianapolis, Indiana 46285, USA
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