1
|
Keller BN, Hajnal A, Browning KN, Arnold AC, Silberman Y. Involvement of the Dorsal Vagal Complex in Alcohol-Related Behaviors. Front Behav Neurosci 2022; 16:801825. [PMID: 35330845 PMCID: PMC8940294 DOI: 10.3389/fnbeh.2022.801825] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 01/19/2022] [Indexed: 12/20/2022] Open
Abstract
The neurobiological mechanisms that regulate the development and maintenance of alcohol use disorder (AUD) are complex and involve a wide variety of within and between systems neuroadaptations. While classic reward, preoccupation, and withdrawal neurocircuits have been heavily studied in terms of AUD, viable treatment targets from this established literature have not proven clinically effective as of yet. Therefore, examination of additional neurocircuitries not classically studied in the context of AUD may provide novel therapeutic targets. Recent studies demonstrate that various neuropeptides systems are important modulators of alcohol reward, seeking, and intake behaviors. This includes neurocircuitry within the dorsal vagal complex (DVC), which is involved in the control of the autonomic nervous system, control of intake of natural rewards like food, and acts as a relay of interoceptive sensory information via interactions of numerous gut-brain peptides and neurotransmitter systems with DVC projections to central and peripheral targets. DVC neuron subtypes produce a variety of neuropeptides and transmitters and project to target brain regions critical for reward such as the mesolimbic dopamine system as well as other limbic areas important for the negative reinforcing and aversive properties of alcohol withdrawal such as the extended amygdala. This suggests the DVC may play a role in the modulation of various aspects of AUD. This review summarizes the current literature on neurotransmitters and neuropeptides systems in the DVC (e.g., norepinephrine, glucagon-like peptide 1, neurotensin, cholecystokinin, thyrotropin-releasing hormone), and their potential relevance to alcohol-related behaviors in humans and rodent models for AUD research. A better understanding of the role of the DVC in modulating alcohol related behaviors may lead to the elucidation of novel therapeutic targets for drug development in AUD.
Collapse
|
2
|
Psilopanagioti A, Makrygianni M, Nikou S, Logotheti S, Papadaki H. Nucleobindin 2/nesfatin-1 expression and colocalisation with neuropeptide Y and cocaine- and amphetamine-regulated transcript in the human brainstem. J Neuroendocrinol 2020; 32:e12899. [PMID: 32902020 DOI: 10.1111/jne.12899] [Citation(s) in RCA: 2] [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: 03/05/2020] [Revised: 08/03/2020] [Accepted: 08/04/2020] [Indexed: 11/26/2022]
Abstract
Feeding is a complex behaviour entailing elaborate interactions between forebrain, hypothalamic and brainstem neuronal circuits via multiple orexigenic and anorexigenic neuropeptides. Nucleobindin-2 (NUCB2)/nesfatin-1 is a negative regulator of food intake and body weight with a widespread distribution in rodent brainstem nuclei. However, its localisation pattern in the human brainstem is unknown. The present study aimed to explore NUCB2/nesfatin-1 immunoexpression in human brainstem nuclei and its possible correlation with body weight. Sections of human brainstem from 20 autopsy cases (13 males, seven females; eight normal weight, six overweight, six obese) were examined using immunohistochemistry and double immunofluorescence labelling. Strong immunoreactivity for NUCB2/nesfatin-1 was displayed in various brainstem areas, including the locus coeruleus, medial and lateral parabrachial nuclei, pontine nuclei, raphe nuclei, nucleus of the solitary tract, dorsal motor nucleus of vagus (10N), area postrema, hypoglossal nucleus, reticular formation, inferior olive, cuneate nucleus, and spinal trigeminal nucleus. NUCB2/nesfatin-1 was shown to extensively colocalise with neuropeptide Y and cocaine- and amphetamine-regulated transcript in the locus coeruleus, dorsal raphe nucleus and solitary tract. Interestingly, in the examined cases, NUCB2/nesfatin-1 protein expression was lower in obese than normal weight subjects in the solitary tract (P = 0.020). The findings of the present study provide neuroanatomical support for a role for NUCB2/nesfatin-1 in feeding behaviour and energy balance. The widespread distribution of NUCB2/nesfatin-1 in the human brainstem nuclei may be indicative of its pleiotropic effects on autonomic, neuroendocrine and behavioural processes. In the solitary tract, a key integrator of energy status, altered neurochemistry may contribute to obesity. Further research is necessary to decipher human brainstem energy homeostasis circuitry, which, despite its importance, remains inadequately characterised.
Collapse
Affiliation(s)
- Aristea Psilopanagioti
- Department of Anatomy-Histology-Embryology, School of Medicine, University of Patras, Patras, Greece
| | - Maria Makrygianni
- Department of Anatomy-Histology-Embryology, School of Medicine, University of Patras, Patras, Greece
| | - Sofia Nikou
- Department of Anatomy-Histology-Embryology, School of Medicine, University of Patras, Patras, Greece
| | - Souzana Logotheti
- Department of Pathology, School of Medicine, University of Patras, Patras, Greece
| | - Helen Papadaki
- Department of Anatomy-Histology-Embryology, School of Medicine, University of Patras, Patras, Greece
| |
Collapse
|
3
|
Worth AA, Shoop R, Tye K, Feetham CH, D'Agostino G, Dodd GT, Reimann F, Gribble FM, Beebe EC, Dunbar JD, Alexander-Chacko JT, Sindelar DK, Coskun T, Emmerson PJ, Luckman SM. The cytokine GDF15 signals through a population of brainstem cholecystokinin neurons to mediate anorectic signalling. eLife 2020; 9:55164. [PMID: 32723474 PMCID: PMC7410488 DOI: 10.7554/elife.55164] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 07/26/2020] [Indexed: 02/02/2023] Open
Abstract
The cytokine, GDF15, is produced in pathological states which cause cellular stress, including cancer. When over expressed, it causes dramatic weight reduction, suggesting a role in disease-related anorexia. Here, we demonstrate that the GDF15 receptor, GFRAL, is located in a subset of cholecystokinin neurons which span the area postrema and the nucleus of the tractus solitarius of the mouse. GDF15 activates GFRALAP/NTS neurons and supports conditioned taste and place aversions, while the anorexia it causes can be blocked by a monoclonal antibody directed at GFRAL or by disrupting CCK neuronal signalling. The cancer-therapeutic drug, cisplatin, induces the release of GDF15 and activates GFRALAP/NTS neurons, as well as causing significant reductions in food intake and body weight in mice. These metabolic effects of cisplatin are abolished by pre-treatment with the GFRAL monoclonal antibody. Our results suggest that GFRAL neutralising antibodies or antagonists may provide a co-treatment opportunity for patients undergoing chemotherapy.
Collapse
Affiliation(s)
- Amy A Worth
- Faculty of Biology, Medicine and Health, The University of ManchesterManchesterUnited Kingdom
| | - Rosemary Shoop
- Faculty of Biology, Medicine and Health, The University of ManchesterManchesterUnited Kingdom
| | - Katie Tye
- Faculty of Biology, Medicine and Health, The University of ManchesterManchesterUnited Kingdom
| | - Claire H Feetham
- Faculty of Biology, Medicine and Health, The University of ManchesterManchesterUnited Kingdom
| | - Giuseppe D'Agostino
- Faculty of Biology, Medicine and Health, The University of ManchesterManchesterUnited Kingdom,Rowett Institute, University of AberdeenAberdeenUnited Kingdom
| | - Garron T Dodd
- School of Biomedical Sciences, The University of MelbourneVictoriaAustralia
| | - Frank Reimann
- Institute of Metabolic Science, Addenbrooke’s HospitalCambridgeUnited Kingdom
| | - Fiona M Gribble
- Institute of Metabolic Science, Addenbrooke’s HospitalCambridgeUnited Kingdom
| | - Emily C Beebe
- Lilly Research Laboratories, Eli Lilly & CompanyIndianapolisUnited States
| | - James D Dunbar
- Lilly Research Laboratories, Eli Lilly & CompanyIndianapolisUnited States
| | | | - Dana K Sindelar
- Lilly Research Laboratories, Eli Lilly & CompanyIndianapolisUnited States
| | - Tamer Coskun
- Lilly Research Laboratories, Eli Lilly & CompanyIndianapolisUnited States
| | - Paul J Emmerson
- Lilly Research Laboratories, Eli Lilly & CompanyIndianapolisUnited States
| | - Simon M Luckman
- Faculty of Biology, Medicine and Health, The University of ManchesterManchesterUnited Kingdom
| |
Collapse
|
4
|
Ganglioside deficiency in hypothalamic POMC neurons promotes body weight gain. Int J Obes (Lond) 2019; 44:510-524. [PMID: 31168055 DOI: 10.1038/s41366-019-0388-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 03/15/2019] [Accepted: 04/05/2019] [Indexed: 11/09/2022]
Abstract
BACKGROUND Glucosylceramide synthase (GCS; gene: UDP-glucose:ceramide glucosyltransferase (Ugcg))-derived gangliosides comprise a specific class of lipids in the plasma membrane that modulate the activity of transmembrane receptors. GCS deletion in hypothalamic arcuate nucleus (Arc) neurons leads to prominent obesity. However, it has not yet been studied how ganglioside depletion affects individual Arc neuronal subpopulations. The current study investigates the effects of GCS deletion specifically in anorexigenic pro-opiomelanocortin (POMC) neurons. Additionally, we investigate insulin receptor (IR) signaling and phosphatidylinositol-(3,4,5)-trisphosphate (PIP3) binding to ATP-dependent K+ (KATP) channels of GCS-deficient POMC neurons. MATERIALS AND METHODS We generated Ugcgf/f-Pomc-Cre mice with ganglioside deficiency in POMC neurons. Moreover, the CRISPR (clustered regulatory interspaced short palindromic repeats)/Cas9 technology was used to inhibit GCS-dependent ganglioside biosynthesis in cultured mouse POMC neurons, yielding UgcgΔ-mHypoA-POMC cells that were used to study mechanistic aspects in further detail. Proximity ligation assays (PLAs) visualized interactions between gangliosides, IR, and KATP channel subunit sulfonylurea receptor-1 (SUR-1), as well as intracellular IR substrate 2 (IRS-2) phosphorylation and PIP3. RESULTS Chow-fed Ugcgf/f-Pomc-Cre mice showed a moderate but significant increase in body weight gain and they failed to display an increase of anorexigenic neuropeptide expression during the fasting-to-re-feeding transition. IR, IRS-2, p85, and overall insulin-evoked IR and IRS-2 phosphorylation were elevated in ganglioside-depleted UgcgΔ-mHypoA-POMC neurons. A PLA demonstrated that more insulin-evoked complex formation occurred between PIP3 and SUR-1 in ganglioside-deficient POMC neurons in vitro and in vivo. CONCLUSION Our work suggests that GCS deletion in POMC neurons promotes body weight gain. Gangliosides are required for an appropriate adaptation of anorexigenic neuropeptide expression in the Arc during the fasting-to-re-feeding transition. Moreover, gangliosides might modulate KATP channel activity by restraining PIP3 binding to the KATP channel subunit SUR-1. Increased PIP3/SUR-1 interactions in ganglioside-deficient neurons could in turn potentially lead to electrical silencing. This work highlights that gangliosides in POMC neurons of the hypothalamic Arc are important regulators of body weight.
Collapse
|
5
|
Barna J, Renner E, Arszovszki A, Cservenák M, Kovács Z, Palkovits M, Dobolyi A. Suckling induced activation pattern in the brain of rat pups. Nutr Neurosci 2017; 21:317-327. [PMID: 28185482 DOI: 10.1080/1028415x.2017.1286446] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVES The aim of the study was to understand the effects of suckling on the brain of the pups by mapping their brain activation pattern in response to suckling. METHODS The c-fos method was applied to identify activated neurons. Fasted rat pups were returned to their mothers for suckling and sacrificed 2 hours later for Fos immunohistochemistry. Double labeling was also performed to characterize some of the activated neurons. For comparison, another group of fasted pups were given dry food before Fos mapping. RESULTS After suckling, we found an increase in the number of Fos-immunoreactive neurons in the insular and somatosensory cortices, central amygdaloid nucleus (CAm), paraventricular (PVN) and supraoptic hypothalamic nuclei, lateral parabrachial nucleus (LPB), nucleus of the solitary tract (NTS), and the area postrema. Double labeling experiments demonstrated the activation of calcitonin gene-related peptide-ir (CGRP-ir) neurons in the LPB, corticotropin-releasing hormone-ir (CRH-ir) but not oxytocin-ir neurons in the PVN, and noradrenergic neurons in the NTS. In the CAm, Fos-ir neurons did not contain CRH but were apposed to CGRP-ir fiber terminals. Refeeding with dry food-induced Fos activation in all brain areas activated by suckling. The degree of activation was higher following dry food consumption than suckling in the insular cortex, and lower in the supraoptic nucleus and the NTS. Furthermore, the accumbens, arcuate, and dorsomedial hypothalamic nuclei, and the lateral hypothalamic area, which were not activated by suckling, showed activation by dry food. DISCUSSION Neurons in a number of brain areas are activated during suckling, and may participate in the signaling of satiety, taste perception, reward, food, and salt balance regulation.
Collapse
Affiliation(s)
- János Barna
- a Laboratory of Neuromorphology, Department of Anatomy, Histology and Embryology , Semmelweis University , Budapest , Hungary
| | - Eva Renner
- b MTA-SOTE NAP_A Human Brain Tissue Bank and Laboratory, Semmelweis University and the Hungarian Academy of Sciences , Budapest , Hungary
| | - Antónia Arszovszki
- c MTA-ELTE NAP_B Laboratory of Molecular and Systems Neurobiology, Department of Physiology and Neurobiology , Eötvös Loránd University and the Hungarian Academy of Sciences , Budapest , Hungary
| | - Melinda Cservenák
- a Laboratory of Neuromorphology, Department of Anatomy, Histology and Embryology , Semmelweis University , Budapest , Hungary.,c MTA-ELTE NAP_B Laboratory of Molecular and Systems Neurobiology, Department of Physiology and Neurobiology , Eötvös Loránd University and the Hungarian Academy of Sciences , Budapest , Hungary
| | - Zsolt Kovács
- d Department of Zoology , University of West Hungary, Savaria Campus , Szombathely , Hungary
| | - Miklós Palkovits
- b MTA-SOTE NAP_A Human Brain Tissue Bank and Laboratory, Semmelweis University and the Hungarian Academy of Sciences , Budapest , Hungary
| | - Arpád Dobolyi
- a Laboratory of Neuromorphology, Department of Anatomy, Histology and Embryology , Semmelweis University , Budapest , Hungary.,c MTA-ELTE NAP_B Laboratory of Molecular and Systems Neurobiology, Department of Physiology and Neurobiology , Eötvös Loránd University and the Hungarian Academy of Sciences , Budapest , Hungary
| |
Collapse
|
6
|
Nordström V, Willershäuser M, Herzer S, Rozman J, von Bohlen Und Halbach O, Meldner S, Rothermel U, Kaden S, Roth FC, Waldeck C, Gretz N, de Angelis MH, Draguhn A, Klingenspor M, Gröne HJ, Jennemann R. Neuronal expression of glucosylceramide synthase in central nervous system regulates body weight and energy homeostasis. PLoS Biol 2013; 11:e1001506. [PMID: 23554574 PMCID: PMC3595213 DOI: 10.1371/journal.pbio.1001506] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 01/31/2013] [Indexed: 01/19/2023] Open
Abstract
Body weight and energy homeostasis are regulated by leptin receptor interactions with gangliosides, a class of plasma membrane lipids, in forebrain neurons of mice. Hypothalamic neurons are main regulators of energy homeostasis. Neuronal function essentially depends on plasma membrane-located gangliosides. The present work demonstrates that hypothalamic integration of metabolic signals requires neuronal expression of glucosylceramide synthase (GCS; UDP-glucose:ceramide glucosyltransferase). As a major mechanism of central nervous system (CNS) metabolic control, we demonstrate that GCS-derived gangliosides interacting with leptin receptors (ObR) in the neuronal membrane modulate leptin-stimulated formation of signaling metabolites in hypothalamic neurons. Furthermore, ganglioside-depleted hypothalamic neurons fail to adapt their activity (c-Fos) in response to alterations in peripheral energy signals. Consequently, mice with inducible forebrain neuron-specific deletion of the UDP-glucose:ceramide glucosyltransferase gene (Ugcg) display obesity, hypothermia, and lower sympathetic activity. Recombinant adeno-associated virus (rAAV)-mediated Ugcg delivery to the arcuate nucleus (Arc) significantly ameliorated obesity, specifying gangliosides as seminal components for hypothalamic regulation of body energy homeostasis. Obesity is a growing health threat that affects nearly half a billion people worldwide, and its incidence rates in lower income countries are rising dramatically. As obesity is a major risk factor for type II diabetes and cardiovascular disease, significant effort has been put into the exploration of causes, prevention, and potential treatment. Recent research has demonstrated that a region of the brain called the hypothalamus is a major integrator of metabolic and nutrient signals, adapting food intake and energy expenditure to current metabolic needs. Leptin or insulin receptors located in the plasma cell membrane of neurons sense energy signals from the body. They transmit this information inside the cell, which then regulates neuronal function. In this study, we show that leptin receptors interact with gangliosides, a class of plasma membrane lipids. This interaction is a prerequisite for proper receptor activation. Consequently, ganglioside loss in hypothalamic neurons inhibits leptin receptor signal transduction in response to energy metabolites. Furthermore, mice lacking gangliosides in distinct forebrain areas, amongst them the hypothalamus, develop progressive obesity and hypothermia. Our results suggest a previously unknown regulatory mechanism of plasma membrane lipids for hypothalamic control of body weight.
Collapse
Affiliation(s)
- Viola Nordström
- Department of Cellular and Molecular Pathology, German Cancer Research Center, Heidelberg, Germany.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Maniscalco JW, Kreisler AD, Rinaman L. Satiation and stress-induced hypophagia: examining the role of hindbrain neurons expressing prolactin-releasing Peptide or glucagon-like Peptide 1. Front Neurosci 2013; 6:199. [PMID: 23346044 PMCID: PMC3549516 DOI: 10.3389/fnins.2012.00199] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 12/31/2012] [Indexed: 12/20/2022] Open
Abstract
Neural circuits distributed within the brainstem, hypothalamus, and limbic forebrain interact to control food intake and energy balance under normal day-to-day conditions, and in response to stressful conditions under which homeostasis is threatened. Experimental studies using rats and mice have generated a voluminous literature regarding the functional organization of circuits that inhibit food intake in response to satiety signals, and in response to stress. Although the central neural bases of satiation and stress-induced hypophagia often are studied and discussed as if they were distinct, we propose that both behavioral states are generated, at least in part, by recruitment of two separate but intermingled groups of caudal hindbrain neurons. One group comprises a subpopulation of noradrenergic (NA) neurons within the caudal nucleus of the solitary tract (cNST; A2 cell group) that is immunopositive for prolactin-releasing peptide (PrRP). The second group comprises non-adrenergic neurons within the cNST and nearby reticular formation that synthesize glucagon-like peptide 1 (GLP-1). Axonal projections from PrRP and GLP-1 neurons target distributed brainstem and forebrain regions that shape behavioral, autonomic, and endocrine responses to actual or anticipated homeostatic challenge, including the challenge of food intake. Evidence reviewed in this article supports the view that hindbrain PrRP and GLP-1 neurons contribute importantly to satiation and stress-induced hypophagia by modulating the activity of caudal brainstem circuits that control food intake. Hindbrain PrRP and GLP-1 neurons also engage hypothalamic and limbic forebrain networks that drive parallel behavioral and endocrine functions related to food intake and homeostatic challenge, and modulate conditioned and motivational aspects of food intake.
Collapse
Affiliation(s)
- James W Maniscalco
- Department of Neuroscience, University of Pittsburgh Pittsburgh, PA, USA
| | | | | |
Collapse
|
8
|
McAllan L, Cotter PD, Roche HM, Korpela R, Nilaweera KN. Impact of leucine on energy balance. J Physiol Biochem 2012; 69:155-63. [PMID: 22535285 DOI: 10.1007/s13105-012-0170-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Accepted: 04/10/2012] [Indexed: 12/14/2022]
Abstract
Body weight is determined by the balance between energy intake and energy expenditure. When energy intake exceeds energy expenditure, the surplus energy is stored as fat in the adipose tissue, which causes its expansion and may even lead to the development of obesity. Thus, there is a growing interest to develop dietary interventions that could reduce the current obesity epidemic. In this regard, data from a number of in vivo and in vitro studies suggest that the branched-chain amino acid leucine influences energy balance. However, this has not been consistently reported. Here, we review the literature related to the effects of leucine on energy intake, energy expenditure and lipid metabolism as well as its effects on the cellular activity in the brain (hypothalamus) and in peripheral tissues (gastro-intestinal tract, adipose tissue, liver and muscle) regulating the above physiological processes. Moreover, we discuss how obesity may influence the actions of this amino acid.
Collapse
Affiliation(s)
- Liam McAllan
- Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland
| | | | | | | | | |
Collapse
|
9
|
Rinaman L. Ascending projections from the caudal visceral nucleus of the solitary tract to brain regions involved in food intake and energy expenditure. Brain Res 2010; 1350:18-34. [PMID: 20353764 DOI: 10.1016/j.brainres.2010.03.059] [Citation(s) in RCA: 209] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 03/15/2010] [Accepted: 03/15/2010] [Indexed: 01/16/2023]
Abstract
Metabolic homeostasis reflects the complex output of endocrine, autonomic, and behavioral control circuits that extend throughout the central nervous system. Brain regions that control food intake and energy expenditure are privy to continuous visceral sensory feedback signals that presumably modulate appetite, satiety, digestion, and metabolism. Sensory signals from the gastrointestinal tract and associated digestive viscera are delivered to the brain primarily by vagal afferents that terminate centrally within the caudal nucleus of the solitary tract (NST), with signals subsequently relayed to higher brain regions by parallel noradrenergic and peptidergic projection pathways arising within the NST. This article begins with an overview of these ascending pathways identified in adult rats using a standard anterograde tracer microinjected into the caudal visceral sensory region of the NST, and also by immunocytochemical localization of glucagon-like peptide-1. NST projection targets identified by these two approaches are compared to the distribution of neurons that become infected after inoculating the ventral stomach wall with a neurotropic virus that transneuronally infects synaptically-linked chains of neurons in the anterograde (i.e., ascending sensory) direction. Although the focus of this article is the anatomical organization of axonal projections from the caudal visceral NST to the hypothalamus and limbic forebrain, discussion is included regarding the hypothesized role of these projections in modulating behavioral arousal and coordinating endocrine and behavioral (i.e., hypophagic) responses to stress.
Collapse
Affiliation(s)
- Linda Rinaman
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA 15260, USA.
| |
Collapse
|
10
|
Renner E, Szabó-Meltzer KI, Puskás N, Tóth ZE, Dobolyi A, Palkovits M. Activation of neurons in the hypothalamic dorsomedial nucleus via hypothalamic projections of the nucleus of the solitary tract following refeeding of fasted rats. Eur J Neurosci 2010; 31:302-14. [PMID: 20074225 DOI: 10.1111/j.1460-9568.2009.07053.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
We report that satiation evokes neuronal activity in the ventral subdivision of the hypothalamic dorsomedial nucleus (DMH) as indicated by increased c-fos expression in response to refeeding in fasted rats. The absence of significant Fos activation following food presentation without consumption suggests that satiation but not craving for food elicits the activation of ventral DMH neurons. The distribution pattern of the prolactin-releasing peptide (PrRP)-immunoreactive (ir) network showed remarkable correlations with the distribution of activated neurons within the DMH. The PrRP-ir fibers and terminals were immunolabeled with tyrosine hydroxylase, suggesting their origin in lower brainstem instead of local, hypothalamic PrRP cells. PrRP-ir fibers arising from neurons of the nucleus of the solitary tract could be followed to the hypothalamus. Unilateral transections of these fibers at pontine and caudal hypothalamic levels resulted in a disappearance of the dense PrRP-ir network in the ventral DMH while PrRP immunoreactivity was increased in transected fibers caudal to the knife cuts as well as in perikarya of the nucleus of the solitary tract ipsilateral to the transections. In accord with these changes, the number of Fos-expressing neurons following refeeding declined in the ipsilateral but remained high in the contralateral DMH. However, the Fos response in the ventral DMH was not attenuated following chemical lesion (neonatal monosodium glutamate treatment) of the hypothalamic arcuate nucleus, another possible source of DMH inputs. These findings suggest that PrRP projections from the nucleus of the solitary tract contribute to the activation of ventral DMH neurons during refeeding, possibly by transferring information on cholecystokinin-mediated satiation.
Collapse
Affiliation(s)
- Eva Renner
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
| | | | | | | | | | | |
Collapse
|
11
|
Jelsing J, Galzin AM, Guillot E, Pruniaux MP, Larsen PJ, Vrang N. Localization and phenotypic characterization of brainstem neurons activated by rimonabant and WIN55,212-2. Brain Res Bull 2009; 78:202-10. [DOI: 10.1016/j.brainresbull.2008.10.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Revised: 10/21/2008] [Accepted: 10/27/2008] [Indexed: 11/25/2022]
|
12
|
|
13
|
Maletínská L, Maixnerová J, Matysková R, Haugvicová R, Pirník Z, Kiss A, Zelezná B. Synergistic effect of CART (cocaine- and amphetamine-regulated transcript) peptide and cholecystokinin on food intake regulation in lean mice. BMC Neurosci 2008; 9:101. [PMID: 18939974 PMCID: PMC2587474 DOI: 10.1186/1471-2202-9-101] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Accepted: 10/21/2008] [Indexed: 11/25/2022] Open
Abstract
Background CART (cocaine- and amphetamine-regulated transcript) peptide and cholecystokinin (CCK) are neuromodulators involved in feeding behavior. This study is based on previously found synergistic effect of leptin and CCK on food intake and our hypothesis on a co-operation of the CART peptide and CCK in food intake regulation and Fos activation in their common targets, the nucleus tractus solitarii of the brainstem (NTS), the paraventricular nucleus (PVN), and the dorsomedial nucleus (DMH) of the hypothalamus. Results In fasted C57BL/6 mice, the anorexigenic effect of CART(61-102) in the doses of 0.1 or 0.5 μg/mouse was significantly enhanced by low doses of CCK-8 of 0.4 or 4 μg/kg, while 1 mg/kg dose of CCK-A receptor antagonist devazepide blocked the effect of CART(61-102) on food intake. After simultaneous administration of 0.1 μg/mouse CART(61-102) and of 4 μg/kg of CCK-8, the number of Fos-positive neurons in NTS, PVN, and DMH was significantly higher than after administration of each particular peptide. Besides, CART(61-102) and CCK-8 showed an additive effect on inhibition of the locomotor activity of mice in an open field test. Conclusion The synergistic and long-lasting effect of the CART peptide and CCK on food intake and their additive effect on Fos immunoreactivity in their common targets suggest a co-operative action of CART peptide and CCK which could be related to synergistic effect of leptin on CCK satiety.
Collapse
Affiliation(s)
- Lenka Maletínská
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám, 2, 16610 Prague 6, Czech Republic.
| | | | | | | | | | | | | |
Collapse
|
14
|
Polakof S, Míguez JM, Soengas JL. Dietary carbohydrates induce changes in glucosensing capacity and food intake of rainbow trout. Am J Physiol Regul Integr Comp Physiol 2008; 295:R478-89. [DOI: 10.1152/ajpregu.00176.2008] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We hypothesize that variations in dietary carbohydrate levels produce changes in glucosensor parameters in previously characterized glucosensing areas (hypothalamus and hindbrain) related with the regulation of food intake of a carnivorous fish species like rainbow trout. Therefore, we fed trout with standard, carbohydrate-free (CF) or high-carbohydrate (HC) diets for 10 days to assess changes in glucosensing system and food intake. Fish fed CF diet displayed hypoglycemia and increased food intake. Fish fed a HC diet displayed hyperglycemia and decreased food intake. Changes in food intake due to dietary carbohydrates were accompanied in hypothalamus and hindbrain of fish fed with HC diet by changes in parameters involved in glucosensing, such as increased glucose, glucose 6-phosphate, and glycogen levels and increased glucokinase (GK), glycogen synthase, and pyruvate kinase activities as well as increased GK and GLUT2 expression. All those results address for the first time in fish, despite the relative intolerance to glucose of carnivorous species, that dietary carbohydrates are important regulators of the glucosensing system in carnivorous fish, suggesting that the information generated by this system can be associated with the changes observed in food intake.
Collapse
|
15
|
|
16
|
Sanger GJ, Lee K. Hormones of the gut-brain axis as targets for the treatment of upper gastrointestinal disorders. Nat Rev Drug Discov 2008; 7:241-54. [PMID: 18309313 DOI: 10.1038/nrd2444] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The concept of the gut forming the centre of an integrated gut-brain-energy axis - modulating appetite, metabolism and digestion - opens up new paradigms for drugs that can tackle multiple symptoms in complex upper gastrointestinal disorders. These include eating disorders, nausea and vomiting, gastroesophageal reflux disease, gastroparesis, dyspepsia and irritable bowel syndrome. The hormones that modulate gastric motility represent targets for gastric prokinetic drugs, and peptides that modify eating behaviours may be targeted to develop drugs that reduce nausea, a currently poorly treated condition. The gut-brain axis may therefore provide a range of therapeutic opportunities that deliver a more holistic treatment of upper gastrointestinal disorders.
Collapse
Affiliation(s)
- Gareth J Sanger
- Immuno Inflammation Centre of Excellence for Drug Discovery, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, UK.
| | | |
Collapse
|
17
|
Novak CM, Levine JA. Central neural and endocrine mechanisms of non-exercise activity thermogenesis and their potential impact on obesity. J Neuroendocrinol 2007; 19:923-40. [PMID: 18001322 DOI: 10.1111/j.1365-2826.2007.01606.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The rise in obesity is associated with a decline in the amount of physical activity in which people engage. The energy expended through everyday non-exercise activity, called non-exercise activity thermogenesis (NEAT), has a considerable potential impact on energy balance and weight gain. Comparatively little attention has been paid to the central mechanisms of energy expenditure and how decreases in NEAT might contribute to obesity. In this review, we first examine the sensory and endocrine mechanisms through which energy availability and energy balance are detected that may influence NEAT. Second, we describe the neural pathways that integrate these signals. Lastly, we consider the effector mechanisms that modulate NEAT through the alteration of activity levels as well as through changes in the energy efficiency of movement. Systems that regulate NEAT according to energy balance may be linked to neural circuits that modulate sleep, addiction and the stress response. The neural and endocrine systems that control NEAT are potential targets for the treatment of obesity.
Collapse
Affiliation(s)
- C M Novak
- Mayo Clinic, Endocrine Research Unit, Rochester, MN, USA.
| | | |
Collapse
|
18
|
Marty N, Dallaporta M, Thorens B. Brain glucose sensing, counterregulation, and energy homeostasis. Physiology (Bethesda) 2007; 22:241-51. [PMID: 17699877 DOI: 10.1152/physiol.00010.2007] [Citation(s) in RCA: 241] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Neuronal circuits in the central nervous system play a critical role in orchestrating the control of glucose and energy homeostasis. Glucose, beside being a nutrient, is also a signal detected by several glucose-sensing units that are located at different anatomical sites and converge to the hypothalamus to cooperate with leptin and insulin in controlling the melanocortin pathway.
Collapse
Affiliation(s)
- Nell Marty
- Department of Physiology and Center for Integrative Genomics, Genopode Building, University of Lausanne, Lausanne, Switzerland
| | | | | |
Collapse
|
19
|
Oldfield BJ, Allen AM, Davern P, Giles ME, Owens NC. Lateral hypothalamic 'command neurons' with axonal projections to regions involved in both feeding and thermogenesis. Eur J Neurosci 2007; 25:2404-12. [PMID: 17445237 DOI: 10.1111/j.1460-9568.2007.05429.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The concept of 'command neurons', whereby single neurons mediate complex and complementary motor functions to generate a stereotyped behaviour, is well developed in invertebrate physiology. The term has also been adopted more recently to explain the neural basis of 'fight or flight'. In this study we have investigated the possibility that single lateral hypothalamic neurons have the necessary neuroanatomical connections to coordinate two complementary limbs of body weight control, feeding and thermogenesis, thereby acting as 'command neurons'. The transynaptic retrograde transport of pseudorabies virus (Bartha) from a thermogenic endpoint in the brown adipose tissue of rats has been used in conjunction with other neuronal tracers, introduced into putative CNS feeding centres, to assess the potential for the involvement of command neurons in coordinating these processes. In discrete regions of the lateral hypothalamus, neurons have been identified which have the necessary complement of orexigenic peptides and collateral branching axons to both putative feeding sites and thermogenic sites in brown fat to qualify as candidate central command neurons controlling body weight.
Collapse
Affiliation(s)
- B J Oldfield
- Department of Physiology, Monash University, Wellington Road, Clayton, Victoria 3800, Australia.
| | | | | | | | | |
Collapse
|
20
|
de Lartigue G, Dimaline R, Varro A, Dockray GJ. Cocaine- and amphetamine-regulated transcript: stimulation of expression in rat vagal afferent neurons by cholecystokinin and suppression by ghrelin. J Neurosci 2007; 27:2876-82. [PMID: 17360909 PMCID: PMC6672594 DOI: 10.1523/jneurosci.5508-06.2007] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The neuropeptide transmitter cocaine- and amphetamine-regulated transcript (CART) inhibits food intake and is expressed by both vagal afferent and hypothalamic neurons. Here we report that cholecystokinin (CCK) regulates CART expression in rat vagal afferent neurons. Thus, CART was virtually undetectable after energy restriction for 24 h, but administration of CCK to fasted rats increased CART immunoreactivity, and refeeding of fasted animals promptly increased CART by a mechanism sensitive to a CCK-1 receptor antagonist. In vagal afferent neurons incubated in serum-free medium, CART was virtually undetectable, whereas the orexigenic peptide melanin-concentrating hormone (MCH) was readily detected. The addition of CCK rapidly induced CART expression and downregulated MCH. Using a CART promoter-luciferase reporter vector transfected into cultured vagal afferent neurons, we showed that CCK stimulation of CART transcription was mediated by activation of protein kinase C and cAMP response element-binding protein (CREB). The action of CCK on CART expression was inhibited by the orexigenic peptide ghrelin, through a mechanism that involved exclusion of phosphorylated CREB from the nucleus. Thus, CCK reciprocally regulates expression of CART and MCH within the same vagal afferent neuron; ghrelin inhibits the effect of CCK at least in part through control of the nuclear localization of phosphoCREB, revealing previously unsuspected modulation of gut-brain signals implicated in control of food intake.
Collapse
Affiliation(s)
- Guillaume de Lartigue
- Physiological Laboratory, School of Biomedical Sciences, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Rod Dimaline
- Physiological Laboratory, School of Biomedical Sciences, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Andrea Varro
- Physiological Laboratory, School of Biomedical Sciences, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Graham J. Dockray
- Physiological Laboratory, School of Biomedical Sciences, University of Liverpool, Liverpool L69 3BX, United Kingdom
| |
Collapse
|
21
|
Sun HD, Malabunga M, Tonra JR, DiRenzo R, Carrick FE, Zheng H, Berthoud HR, McGuinness OP, Shen J, Bohlen P, Leibel RL, Kussie P. Monoclonal antibody antagonists of hypothalamic FGFR1 cause potent but reversible hypophagia and weight loss in rodents and monkeys. Am J Physiol Endocrinol Metab 2007; 292:E964-76. [PMID: 17132826 DOI: 10.1152/ajpendo.00089.2006] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We generated three fully human monoclonal antibody antagonists against fibroblast growth factor receptor-1 (FGFR1) that potently block FGF signaling. We found that antibodies targeting the c-splice form of the receptor (FGFR1c) were anorexigenic when administered intraperitoneally three times weekly to mice, resulting in rapid, dose-dependent weight loss that plateaued (for doses>4 mg/kg) at 35-40% in 2 wk. Animals appeared healthy during treatment and regained their normal body weights and growth trajectories upon clearance of the antibodies from the bloodstream. Measurements of food consumption and energy expenditure indicated that the rapid weight loss was induced primarily by decreased energy intake and not by increased energy expenditure or cachexia and was accompanied by a greater reduction in fat than lean body mass. Hypophagia was not caused through malaise or illness, as indicated by absence of conditioned taste aversion, pica behavior, and decreased need-induced salt intake in rats. In support of a hypothalamic site of action, we found that, after intraperitoneal injections, anti-FGFR1c (IMC-A1), but not a control antibody, accumulated in the median eminence and adjacent mediobasal hypothalamus and that FGFR1c is enriched in the hypothalamus of mice. Furthermore, a single intracerebroventricular administration of 3 microg of IMC-A1 via the 3rd ventricle to mice caused an approximately 36% reduction in food intake and an approximately 6% weight loss within the ensuing 24 h. Our data suggest that FGF signaling through FGFR1c may play a physiological role in hypothalamic feeding circuit and that blocking it leads to hypophagia and weight loss.
Collapse
Affiliation(s)
- Haijun D Sun
- ImClone Systems Inc., 180 Varick St., New York, NY 10014, USA.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Scott V, McDade DM, Luckman SM. Rapid changes in the sensitivity of arcuate nucleus neurons to central ghrelin in relation to feeding status. Physiol Behav 2007; 90:180-5. [PMID: 17078977 DOI: 10.1016/j.physbeh.2006.09.026] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2006] [Revised: 09/11/2006] [Accepted: 09/20/2006] [Indexed: 01/21/2023]
Abstract
Ghrelin, the endogenous ligand for the growth hormone secretagogue (GHS) receptor, stimulates feeding and increases body weight. Systemic ghrelin administration induces the immediate-early gene protein product, c-Fos, in the arcuate nucleus of the hypothalamus (ARC) of satiated rats and this increase is potentiated in fasted rats. The aim of this study was to determine whether potentiation was seen in fasted animals after intracerebroventricular (i.c.v) administration of ghrelin and to identify the hypothalamic nuclei activated by this peptide. In addition we investigated if allowing fasted animals to re-feed for 1 h prior to i.c.v. ghrelin injection affected the c-Fos response. Using c-Fos immunocytochemistry, we demonstrated that i.c.v. ghrelin activated several hypothalamic nuclei, including the ARC, paraventricular nucleus (PVH) and the lateral hypothalamus (LH). The c-Fos response was greater in fasted animals compared with satiated animals. Fasted rats allowed access to food for 1 h prior to central ghrelin administration showed an attenuated response in the ARC, similar to the response seen in fed animals. However, the response in the LH (including in the orexin neurons) was further potentiated. The latter may reflect a connection between the hypothalamus and regions of the brain responding to the reward value of the meal.
Collapse
Affiliation(s)
- Victoria Scott
- Faculty of Life Science, University of Manchester, Stopford Building, Oxford Road, Manchester, M13 9PT, UK
| | | | | |
Collapse
|
23
|
Johnstone LE, Fong TM, Leng G. Neuronal activation in the hypothalamus and brainstem during feeding in rats. Cell Metab 2006; 4:313-21. [PMID: 17011504 DOI: 10.1016/j.cmet.2006.08.003] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2006] [Revised: 07/06/2006] [Accepted: 08/08/2006] [Indexed: 10/24/2022]
Abstract
We trained rats to a regime of scheduled feeding, in which food was available for only 2 hr each day. After 10 days, rats were euthanized at defined times relative to food availability, and their brains were analyzed to map Fos expression in neuronal populations to test the hypothesis that some populations are activated by hunger whereas others are activated by satiety signals. Fos expression accompanied feeding in several hypothalamic and brainstem nuclei. Food ingestion was critical for Fos expression in noradrenergic and non-noradrenergic cells in the nucleus tractus solitarii and area postrema and in the supraoptic nucleus, as well as in melanocortin-containing cells of the arcuate nucleus. However, anticipation of food alone activated other neurons in the arcuate nucleus and in the lateral and ventromedial hypothalamus, including orexin neurons. Thus orexigenic populations are strongly and rapidly activated at the onset of food presentation, followed rapidly by activity in anorexigenic populations when food is ingested.
Collapse
Affiliation(s)
- Louise E Johnstone
- Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh EH8 9XD, United Kingdom.
| | | | | |
Collapse
|
24
|
Mieda M, Williams SC, Richardson JA, Tanaka K, Yanagisawa M. The dorsomedial hypothalamic nucleus as a putative food-entrainable circadian pacemaker. Proc Natl Acad Sci U S A 2006; 103:12150-5. [PMID: 16880388 PMCID: PMC1567710 DOI: 10.1073/pnas.0604189103] [Citation(s) in RCA: 234] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Temporal restriction of feeding can phase-shift behavioral and physiological circadian rhythms in mammals. These changes in biological rhythms are postulated to be brought about by a food-entrainable oscillator (FEO) that is independent of the suprachiasmatic nucleus. However, the neural substrates of FEO have remained elusive. Here, we carried out an unbiased search for mouse brain region(s) that exhibit a rhythmic expression of the Period genes in a feeding-entrainable manner. We found that the compact part of the dorsomedial hypothalamic nucleus (DMH) demonstrates a robust oscillation of mPer expression only under restricted feeding. The oscillation persisted for at least 2 days even when mice were given no food during the expected feeding period after the establishment of food-entrained behavioral rhythms. Moreover, refeeding after fasting rapidly induced a transient mPer expression in the same area of DMH. Taken in conjunction with recent findings (i) that behavioral expression of food-entrainable circadian rhythms is blocked by cell-specific lesions of DMH in rats and (ii) that DMH neurons directly project to orexin neurons in the lateral hypothalamus, which are essential for proper expression of food-entrained behavioral rhythms, the present study suggests that DMH plays a key role as a central FEO in the feeding-mediated regulation of circadian behaviors.
Collapse
Affiliation(s)
- Michihiro Mieda
- *Laboratory of Molecular Neuroscience, School of Biomedical Science and Medical Research Institute, Tokyo Medical and Dental University, Tokyo 113-8519, Japan
- Departments of Molecular Genetics and
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390-9050; and
| | - S. Clay Williams
- Departments of Molecular Genetics and
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390-9050; and
| | | | - Kohichi Tanaka
- *Laboratory of Molecular Neuroscience, School of Biomedical Science and Medical Research Institute, Tokyo Medical and Dental University, Tokyo 113-8519, Japan
| | - Masashi Yanagisawa
- Departments of Molecular Genetics and
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390-9050; and
- Exploratory Research for Advanced Technology, Yanagisawa Orphan Receptor Project, Japan Science and Technology Agency, Tokyo 135-0064, Japan
- To whom correspondence should be addressed. E-mail:
| |
Collapse
|
25
|
Burdyga G, Lal S, Varro A, Dimaline R, Thompson DG, Dockray GJ. Expression of cannabinoid CB1 receptors by vagal afferent neurons is inhibited by cholecystokinin. J Neurosci 2004; 24:2708-15. [PMID: 15028763 PMCID: PMC6729520 DOI: 10.1523/jneurosci.5404-03.2004] [Citation(s) in RCA: 214] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Both inhibitory (satiety) and stimulatory (orexigenic) factors from the gastrointestinal tract regulate food intake. In the case of the satiety hormone cholecystokinin (CCK), these effects are mediated via vagal afferent neurons. We now report that vagal afferent neurons expressing the CCK-1 receptor also express cannabinoid CB1 receptors. Retrograde tracing established that these neurons project to the stomach and duodenum. The expression of CB1 receptors determined by RT-PCR, immunohistochemistry and in situ hybridization in rat nodose ganglia was increased by withdrawal of food for > or =12 hr. After refeeding of fasted rats there was a rapid loss of CB1 receptor expression identified by immunohistochemistry and in situ hybridization. These effects were blocked by administration of the CCK-1 receptor antagonist lorglumide and mimicked by administration of CCK to fasted rats. Because CCK is a satiety factor that acts via the vagus nerve and CB1 agonists stimulate food intake, the data suggest a new mechanism modulating the effect on food intake of satiety signals from the gastrointestinal tract.
Collapse
MESH Headings
- Animals
- Cholecystokinin/pharmacology
- Cholecystokinin/physiology
- Culture Techniques
- Duodenum/innervation
- Food Deprivation/physiology
- Hormone Antagonists/pharmacology
- Humans
- Immunohistochemistry
- In Situ Hybridization
- Male
- Nerve Crush
- Neurons, Afferent/metabolism
- Nodose Ganglion/cytology
- Nodose Ganglion/metabolism
- Proglumide/analogs & derivatives
- Proglumide/pharmacology
- Rats
- Rats, Wistar
- Receptor, Cannabinoid, CB1/antagonists & inhibitors
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/biosynthesis
- Receptor, Cannabinoid, CB2/genetics
- Receptor, Cholecystokinin A/antagonists & inhibitors
- Receptor, Cholecystokinin A/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Satiety Response/physiology
- Stomach/innervation
- Vagus Nerve/cytology
- Vagus Nerve/metabolism
Collapse
Affiliation(s)
- Galina Burdyga
- Physiological Laboratory, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | | | | | | | | | | |
Collapse
|
26
|
Abstract
Neuropeptides terminating in -Arg-Phe-NH(2) (-RFamide) were first discovered in molluscan nervous systems, but were soon recognized to occur widely throughout the invertebrates. Progress in characterizing members of the family in vertebrates has been slower. In mammals, however, it is now clear that there are at least five genes encoding members of the family, and at least five G-protein-coupled receptors at which they act. The tissue distribution of the peptides and their receptors is wide and there are likely to be many different functions. One of the emerging themes from recent research is that these peptides are involved in control of feeding behaviour both in invertebrates and in vertebrates. This would seem to be a remarkable example of conservation of chemical structure and biological function throughout nervous system evolution.
Collapse
Affiliation(s)
- Graham J Dockray
- Physiological Laboratory, University of Liverpool, Crown Street, Liverpool L69 3BX, UK.
| |
Collapse
|