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Oh JY, Lee H, Jang SY, Kim H, Park G, Serikov A, Jang JH, Kim J, Yang S, Sa M, Lee SE, Han YE, Hwang TY, Jung SJ, Kim HY, Lee SE, Oh SJ, Kim J, Kim J, Kim J, McHugh TJ, Lee CJ, Nam MH, Park HJ. Central Role of Hypothalamic Circuits for Acupuncture's Anti-Parkinsonian Effects. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2403245. [PMID: 39119926 DOI: 10.1002/advs.202403245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 06/30/2024] [Indexed: 08/10/2024]
Abstract
Despite clinical data stretching over millennia, the neurobiological basis of the effectiveness of acupuncture in treating diseases of the central nervous system has remained elusive. Here, using an established model of acupuncture treatment in Parkinson's disease (PD) model mice, we show that peripheral acupuncture stimulation activates hypothalamic melanin-concentrating hormone (MCH) neurons via nerve conduction. We further identify two separate neural pathways originating from anatomically and electrophysiologically distinct MCH neuronal subpopulations, projecting to the substantia nigra and hippocampus, respectively. Through chemogenetic manipulation specifically targeting these MCH projections, their respective roles in mediating the acupuncture-induced motor recovery and memory improvements following PD onset are demonstrated, as well as the underlying mechanisms mediating recovery from dopaminergic neurodegeneration, reactive gliosis, and impaired hippocampal synaptic plasticity. Collectively, these MCH neurons constitute not only a circuit-based explanation for the therapeutic effectiveness of traditional acupuncture, but also a potential cellular target for treating both motor and non-motor PD symptoms.
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Affiliation(s)
- Ju-Young Oh
- College of Korean Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
- Studies of Translational Acupuncture Research (STAR), Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Hyowon Lee
- College of Korean Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Sun-Young Jang
- College of Korean Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
- Studies of Translational Acupuncture Research (STAR), Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Hyunjin Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
- Department of KHU-KIST Convergence Science and Technology, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Geunhong Park
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Almas Serikov
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Jae-Hwan Jang
- Studies of Translational Acupuncture Research (STAR), Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Junyeop Kim
- Laboratory of Stem Cells & Cell Reprogramming, Department of Chemistry, Dongguk University, Seoul, 04629, Republic of Korea
| | - Seulkee Yang
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Moonsun Sa
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, 34126, Republic of Korea
| | - Sung Eun Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, 34126, Republic of Korea
| | - Young-Eun Han
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Tae-Yeon Hwang
- College of Korean Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
- Studies of Translational Acupuncture Research (STAR), Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Sharon Jiyoon Jung
- Technological Convergence Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Hee Young Kim
- Department of Physiology, Yonsei University, Seoul, 03722, Republic of Korea
| | - Seung Eun Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, 34126, Republic of Korea
- Research Animal Resource Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Soo-Jin Oh
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Jeongjin Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Jeongyeon Kim
- Emotion, Cognition & Behavior Research Group, Korea Brain Research Institute, Daegu, 41062, Republic of Korea
| | - Jongpil Kim
- Laboratory of Stem Cells & Cell Reprogramming, Department of Chemistry, Dongguk University, Seoul, 04629, Republic of Korea
| | - Thomas J McHugh
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
- Laboratory for Circuit and Behavioral Physiology, RIKEN, Wako-shi Saitama, 351-0198, Japan
| | - C Justin Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, 34126, Republic of Korea
| | - Min-Ho Nam
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
- Department of KHU-KIST Convergence Science and Technology, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Hi-Joon Park
- College of Korean Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
- Studies of Translational Acupuncture Research (STAR), Kyung Hee University, Seoul, 02447, Republic of Korea
- Department of KHU-KIST Convergence Science and Technology, Kyung Hee University, Seoul, 02447, Republic of Korea
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Concetti C, Viskaitis P, Grujic N, Duss SN, Privitera M, Bohacek J, Peleg-Raibstein D, Burdakov D. Exploratory Rearing Is Governed by Hypothalamic Melanin-Concentrating Hormone Neurons According to Locus Ceruleus. J Neurosci 2024; 44:e0015242024. [PMID: 38575343 PMCID: PMC11112542 DOI: 10.1523/jneurosci.0015-24.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 03/20/2024] [Accepted: 03/25/2024] [Indexed: 04/06/2024] Open
Abstract
Information seeking, such as standing on tiptoes to look around in humans, is observed across animals and helps survival. Its rodent analog-unsupported rearing on hind legs-was a classic model in deciphering neural signals of cognition and is of intense renewed interest in preclinical modeling of neuropsychiatric states. Neural signals and circuits controlling this dedicated decision to seek information remain largely unknown. While studying subsecond timing of spontaneous behavioral acts and activity of melanin-concentrating hormone (MCH) neurons (MNs) in behaving male and female mice, we observed large MN activity spikes that aligned to unsupported rears. Complementary causal, loss and gain of function, analyses revealed specific control of rear frequency and duration by MNs and MCHR1 receptors. Activity in a key stress center of the brain-the locus ceruleus noradrenaline cells-rapidly inhibited MNs and required functional MCH receptors for its endogenous modulation of rearing. By defining a neural module that both tracks and controls rearing, these findings may facilitate further insights into biology of information seeking.
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Affiliation(s)
- Cristina Concetti
- Department of Health Sciences and Technology, Neuroscience Center Zürich (ZNZ), Swiss Federal Institute of Technology (ETH Zürich), Zürich 8092, Switzerland
| | - Paulius Viskaitis
- Department of Health Sciences and Technology, Neuroscience Center Zürich (ZNZ), Swiss Federal Institute of Technology (ETH Zürich), Zürich 8092, Switzerland
| | - Nikola Grujic
- Department of Health Sciences and Technology, Neuroscience Center Zürich (ZNZ), Swiss Federal Institute of Technology (ETH Zürich), Zürich 8092, Switzerland
| | - Sian N Duss
- Department of Health Sciences and Technology, Neuroscience Center Zürich (ZNZ), Swiss Federal Institute of Technology (ETH Zürich), Zürich 8092, Switzerland
| | - Mattia Privitera
- Department of Health Sciences and Technology, Neuroscience Center Zürich (ZNZ), Swiss Federal Institute of Technology (ETH Zürich), Zürich 8092, Switzerland
| | - Johannes Bohacek
- Department of Health Sciences and Technology, Neuroscience Center Zürich (ZNZ), Swiss Federal Institute of Technology (ETH Zürich), Zürich 8092, Switzerland
| | - Daria Peleg-Raibstein
- Department of Health Sciences and Technology, Neuroscience Center Zürich (ZNZ), Swiss Federal Institute of Technology (ETH Zürich), Zürich 8092, Switzerland
| | - Denis Burdakov
- Department of Health Sciences and Technology, Neuroscience Center Zürich (ZNZ), Swiss Federal Institute of Technology (ETH Zürich), Zürich 8092, Switzerland
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3
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Gan HW, Cerbone M, Dattani MT. Appetite- and Weight-Regulating Neuroendocrine Circuitry in Hypothalamic Obesity. Endocr Rev 2024; 45:309-342. [PMID: 38019584 PMCID: PMC11074800 DOI: 10.1210/endrev/bnad033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 10/25/2023] [Accepted: 11/27/2023] [Indexed: 11/30/2023]
Abstract
Since hypothalamic obesity (HyOb) was first described over 120 years ago by Joseph Babinski and Alfred Fröhlich, advances in molecular genetic laboratory techniques have allowed us to elucidate various components of the intricate neurocircuitry governing appetite and weight regulation connecting the hypothalamus, pituitary gland, brainstem, adipose tissue, pancreas, and gastrointestinal tract. On a background of an increasing prevalence of population-level common obesity, the number of survivors of congenital (eg, septo-optic dysplasia, Prader-Willi syndrome) and acquired (eg, central nervous system tumors) hypothalamic disorders is increasing, thanks to earlier diagnosis and management as well as better oncological therapies. Although to date the discovery of several appetite-regulating peptides has led to the development of a range of targeted molecular therapies for monogenic obesity syndromes, outside of these disorders these discoveries have not translated into the development of efficacious treatments for other forms of HyOb. This review aims to summarize our current understanding of the neuroendocrine physiology of appetite and weight regulation, and explore our current understanding of the pathophysiology of HyOb.
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Affiliation(s)
- Hoong-Wei Gan
- Department of Endocrinology, Great Ormond Street Hospital for Children NHS Foundation Trust, Great Ormond Street, London WC1N 3JH, UK
- Genetics & Genomic Medicine Research & Teaching Department, University College London Great Ormond Street Institute for Child Health, 30 Guilford Street, London WC1N 1EH, UK
| | - Manuela Cerbone
- Department of Endocrinology, Great Ormond Street Hospital for Children NHS Foundation Trust, Great Ormond Street, London WC1N 3JH, UK
- Genetics & Genomic Medicine Research & Teaching Department, University College London Great Ormond Street Institute for Child Health, 30 Guilford Street, London WC1N 1EH, UK
| | - Mehul Tulsidas Dattani
- Department of Endocrinology, Great Ormond Street Hospital for Children NHS Foundation Trust, Great Ormond Street, London WC1N 3JH, UK
- Genetics & Genomic Medicine Research & Teaching Department, University College London Great Ormond Street Institute for Child Health, 30 Guilford Street, London WC1N 1EH, UK
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Kuebler IRK, Suárez M, Wakabayashi KT. Sex differences and sex-specific regulation of motivated behavior by Melanin-concentrating hormone: a short review. Biol Sex Differ 2024; 15:33. [PMID: 38570844 PMCID: PMC10993549 DOI: 10.1186/s13293-024-00608-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Accepted: 03/23/2024] [Indexed: 04/05/2024] Open
Abstract
Recent preclinical research exploring how neuropeptide transmitter systems regulate motivated behavior reveal the increasing importance of sex as a critical biological variable. Neuropeptide systems and their central circuits both contribute to sex differences in a range of motivated behaviors and regulate sex-specific behaviors. In this short review, we explore the current research of how sex as a biological variable influences several distinct motivated behaviors that are modulated by the melanin-concentrating hormone (MCH) neuropeptide system. First, we review how MCH regulates feeding behavior within the context of energy homeostasis differently between male and female rodents. Then, we focus on MCH's role in lactation as a sex-specific process within the context of energy homeostasis. Next, we discuss the sex-specific effects of MCH on maternal behavior. Finally, we summarize the role of MCH in drug-motivated behaviors. While these topics are traditionally investigated from different scientific perspectives, in this short review we discuss how these behaviors share commonalities within the larger context of motivated behaviors, and that sex differences discovered in one area of research may impact our understanding in another. Overall, our review highlights the need for further research into how sex differences in energy regulation associated with reproduction and parental care contribute to regulating motivated behaviors.
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Affiliation(s)
- Isabel R K Kuebler
- Neurocircuitry of Motivated Behavior Laboratory, Department of Psychology, University of Nebraska-Lincoln, Lincoln, NE, 68588-0308, USA
| | - Mauricio Suárez
- Neurocircuitry of Motivated Behavior Laboratory, Department of Psychology, University of Nebraska-Lincoln, Lincoln, NE, 68588-0308, USA
| | - Ken T Wakabayashi
- Neurocircuitry of Motivated Behavior Laboratory, Department of Psychology, University of Nebraska-Lincoln, Lincoln, NE, 68588-0308, USA.
- Rural Drug Addiction Research Center, University of Nebraska-Lincoln, 660 N 12th St., Lincoln, NE, 68588, USA.
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5
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Vetrivelan R, Bandaru SS. Neural Control of REM Sleep and Motor Atonia: Current Perspectives. Curr Neurol Neurosci Rep 2023; 23:907-923. [PMID: 38060134 DOI: 10.1007/s11910-023-01322-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2023] [Indexed: 12/08/2023]
Abstract
PURPOSE OF REVIEW Since the formal discovery of rapid eye movement (REM) sleep in 1953, we have gained a vast amount of knowledge regarding the specific populations of neurons, their connections, and synaptic mechanisms regulating this stage of sleep and its accompanying features. This article discusses REM sleep circuits and their dysfunction, specifically emphasizing recent studies using conditional genetic tools. RECENT FINDINGS Sublaterodorsal nucleus (SLD) in the dorsolateral pons, especially the glutamatergic subpopulation in this region (SLDGlut), are shown to be indispensable for REM sleep. These neurons appear to be single REM generators in the rodent brain and may initiate and orchestrate all REM sleep events, including cortical and hippocampal activation and muscle atonia through distinct pathways. However, several cell groups in the brainstem and hypothalamus may influence SLDGlut neuron activity, thereby modulating REM sleep timing, amounts, and architecture. Damage to SLDGlut neurons or their projections involved in muscle atonia leads to REM behavior disorder, whereas the abnormal activation of this pathway during wakefulness may underlie cataplexy in narcolepsy. Despite some opposing views, it has become evident that SLDGlut neurons are the sole generators of REM sleep and its associated characteristics. Further research should prioritize a deeper understanding of their cellular, synaptic, and molecular properties, as well as the mechanisms that trigger their activation during cataplexy and make them susceptible in RBD.
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Affiliation(s)
- Ramalingam Vetrivelan
- Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, USA.
| | - Sathyajit Sai Bandaru
- Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, USA
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Concetti C, Peleg-Raibstein D, Burdakov D. Hypothalamic MCH Neurons: From Feeding to Cognitive Control. FUNCTION 2023; 5:zqad059. [PMID: 38020069 PMCID: PMC10667013 DOI: 10.1093/function/zqad059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 10/06/2023] [Accepted: 10/11/2023] [Indexed: 12/01/2023] Open
Abstract
Modern neuroscience is progressively elucidating that the classic view positing distinct brain regions responsible for survival, emotion, and cognitive functions is outdated. The hypothalamus demonstrates the interdependence of these roles, as it is traditionally known for fundamental survival functions like energy and electrolyte balance, but is now recognized to also play a crucial role in emotional and cognitive processes. This review focuses on lateral hypothalamic melanin-concentrating hormone (MCH) neurons, producing the neuropeptide MCH-a relatively understudied neuronal population with integrative functions related to homeostatic regulation and motivated behaviors, with widespread inputs and outputs throughout the entire central nervous system. Here, we review early findings and recent literature outlining their role in the regulation of energy balance, sleep, learning, and memory processes.
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Affiliation(s)
- Cristina Concetti
- Neurobehavioural Dynamics Laboratory, ETH Zürich, Schorenstrasse 16, Schwerzenbach 8603, Switzerland
| | - Daria Peleg-Raibstein
- Neurobehavioural Dynamics Laboratory, ETH Zürich, Schorenstrasse 16, Schwerzenbach 8603, Switzerland
| | - Denis Burdakov
- Neurobehavioural Dynamics Laboratory, ETH Zürich, Schorenstrasse 16, Schwerzenbach 8603, Switzerland
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7
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Sa M, Yoo ES, Koh W, Park MG, Jang HJ, Yang YR, Bhalla M, Lee JH, Lim J, Won W, Kwon J, Kwon JH, Seong Y, Kim B, An H, Lee SE, Park KD, Suh PG, Sohn JW, Lee CJ. Hypothalamic GABRA5-positive neurons control obesity via astrocytic GABA. Nat Metab 2023; 5:1506-1525. [PMID: 37653043 DOI: 10.1038/s42255-023-00877-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 07/25/2023] [Indexed: 09/02/2023]
Abstract
The lateral hypothalamic area (LHA) regulates food intake and energy balance. Although LHA neurons innervate adipose tissues, the identity of neurons that regulate fat is undefined. Here we show that GABRA5-positive neurons in LHA (GABRA5LHA) polysynaptically project to brown and white adipose tissues in the periphery. GABRA5LHA are a distinct subpopulation of GABAergic neurons and show decreased pacemaker firing in diet-induced obesity mouse models in males. Chemogenetic inhibition of GABRA5LHA suppresses fat thermogenesis and increases weight gain, whereas gene silencing of GABRA5 in LHA decreases weight gain. In the diet-induced obesity mouse model, GABRA5LHA are tonically inhibited by nearby reactive astrocytes releasing GABA, which is synthesized by monoamine oxidase B (Maob). Gene silencing of astrocytic Maob in LHA facilitates fat thermogenesis and reduces weight gain significantly without affecting food intake, which is recapitulated by administration of a Maob inhibitor, KDS2010. We propose that firing of GABRA5LHA suppresses fat accumulation and selective inhibition of astrocytic GABA is a molecular target for treating obesity.
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Affiliation(s)
- Moonsun Sa
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
| | - Eun-Seon Yoo
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Wuhyun Koh
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Mingu Gordon Park
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Hyun-Jun Jang
- Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Yong Ryoul Yang
- Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Mridula Bhalla
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
- IBS School, University of Science and Technology, Daejeon, Republic of Korea
| | - Jae-Hun Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Jiwoon Lim
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
- IBS School, University of Science and Technology, Daejeon, Republic of Korea
| | - Woojin Won
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Jea Kwon
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Joon-Ho Kwon
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Yejin Seong
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Byungeun Kim
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology, Seoul, Republic of Korea
- Division of Bio-Medical Science and Technology, University of Science and Technology, Daejeon, Republic of Korea
| | - Heeyoung An
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
| | - Seung Eun Lee
- Virus Facility, Research Animal Resource Center, Korea Institute of Science and Technology, Seoul, Republic of Korea
| | - Ki Duk Park
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology, Seoul, Republic of Korea
- Division of Bio-Medical Science and Technology, University of Science and Technology, Daejeon, Republic of Korea
| | - Pann-Ghill Suh
- Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Jong-Woo Sohn
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - C Justin Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea.
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seongbuk-gu, Seoul, Republic of Korea.
- IBS School, University of Science and Technology, Daejeon, Republic of Korea.
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Bouâouda H, Jha PK. Orexin and MCH neurons: regulators of sleep and metabolism. Front Neurosci 2023; 17:1230428. [PMID: 37674517 PMCID: PMC10478345 DOI: 10.3389/fnins.2023.1230428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 08/07/2023] [Indexed: 09/08/2023] Open
Abstract
Sleep-wake and fasting-feeding are tightly coupled behavioral states that require coordination between several brain regions. The mammalian lateral hypothalamus (LH) is a functionally and anatomically complex brain region harboring heterogeneous cell populations that regulate sleep, feeding, and energy metabolism. Significant attempts were made to understand the cellular and circuit bases of LH actions. Rapid advancements in genetic and electrophysiological manipulation help to understand the role of discrete LH cell populations. The opposing action of LH orexin/hypocretin and melanin-concentrating hormone (MCH) neurons on metabolic sensing and sleep-wake regulation make them the candidate to explore in detail. This review surveys the molecular, genetic, and neuronal components of orexin and MCH signaling in the regulation of sleep and metabolism.
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Affiliation(s)
- Hanan Bouâouda
- Pharmacology Institute, Medical Faculty Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Pawan Kumar Jha
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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Beekly BG, Rupp A, Burgess CR, Elias CF. Fast neurotransmitter identity of MCH neurons: Do contents depend on context? Front Neuroendocrinol 2023; 70:101069. [PMID: 37149229 PMCID: PMC11190671 DOI: 10.1016/j.yfrne.2023.101069] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 04/07/2023] [Accepted: 04/29/2023] [Indexed: 05/08/2023]
Abstract
Hypothalamic melanin-concentrating hormone (MCH) neurons participate in many fundamental neuroendocrine processes. While some of their effects can be attributed to MCH itself, others appear to depend on co-released neurotransmitters. Historically, the subject of fast neurotransmitter co-release from MCH neurons has been contentious, with data to support MCH neurons releasing GABA, glutamate, both, and neither. Rather than assuming a position in that debate, this review considers the evidence for all sides and presents an alternative explanation: neurochemical identity, including classical neurotransmitter content, is subject to change. With an emphasis on the variability of experimental details, we posit that MCH neurons may release GABA and/or glutamate at different points according to environmental and contextual factors. Through the lens of the MCH system, we offer evidence that the field of neuroendocrinology would benefit from a more nuanced and dynamic interpretation of neurotransmitter identity.
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Affiliation(s)
- B G Beekly
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States; Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, United States; Elizabeth W. Caswell Diabetes Institute, University of Michigan, Ann Arbor, MI, United States.
| | - A Rupp
- Elizabeth W. Caswell Diabetes Institute, University of Michigan, Ann Arbor, MI, United States
| | - C R Burgess
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States; Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, United States; Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, United States
| | - C F Elias
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States; Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, United States; Elizabeth W. Caswell Diabetes Institute, University of Michigan, Ann Arbor, MI, United States
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10
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Takakura AC. A new neuromodulatory mechanism in the lateral hypothalamus regulating the hypercapnic ventilatory response in conscious rats. Exp Physiol 2022; 107:1212-1213. [PMID: 35969214 DOI: 10.1113/ep090733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 08/11/2022] [Indexed: 11/08/2022]
Affiliation(s)
- Ana C Takakura
- Department of Pharmacology, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, SP, 05508-000, Brazil
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11
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Rodrigues LTC, Patrone LGA, Gargaglioni LH, Dias MB. Melanin-concentrating hormone regulates the hypercapnic chemoreflex by acting in the lateral hypothalamic area. Exp Physiol 2022; 107:1298-1311. [PMID: 35930596 DOI: 10.1113/ep090318] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 07/22/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? MCH suppresses the hypercapnic chemoreflex but the mechanism by which this effect is produced has not been previously explored. What is the main finding and its importance? MCH acting in the lateral hypothalamic area but not in the locus coeruleus in rats, in the light period, attenuates the hypercapnic chemoreflex. Our data provide new insight regarding the role of MCH in the modulation of the hypercapnic ventilatory response. ABSTRACT Melanin-concentrating hormone (MCH) is a hypothalamic neuropeptide involved in a broad range of homeostatic functions including regulation of the hypercapnic chemoreflex. We evaluated whether MCH modulates the hypercapnic ventilatory response by acting in the lateral hypothalamic area (LHA) and/or in the locus coeruleus (LC). Here, we measured pulmonary ventilation (VE ), body temperature, electroencephalogram (EEG) and electromyogram (EMG) of unanesthetized adult male Wistar rats before and after microinjection of MCH [0.4 mM] or MCH1-R antagonist (SNAP-94847 [63 mM]) into the LHA and LC, in room air and 7% CO2 conditions during wakefulness and sleep, in the dark and light periods. MCH intra-LHA caused a decreased CO2 ventilatory response during wakefulness and sleep in the light period, while SNAP-94847 intra-LHA increased this response, during wakefulness in the light period. In the LC, MCH or the MCH1-R antagonist caused no change in the hypercapnic ventilatory response. Our results suggest that MCH, in the LHA, exerts an inhibitory modulation of the hypercapnic ventilatory response during the light-inactive period in rats. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Laísa T C Rodrigues
- Department of Structural and Functional Biology, Institute of Biosciences, Sao Paulo State University-UNESP, Botucatu, SP, Brazil
| | - Luis Gustavo A Patrone
- Department of Animal Morphology and Physiology, Sao Paulo State University-FCAV, Jaboticabal, SP, Brazil
| | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, Sao Paulo State University-FCAV, Jaboticabal, SP, Brazil
| | - Mirela B Dias
- Department of Structural and Functional Biology, Institute of Biosciences, Sao Paulo State University-UNESP, Botucatu, SP, Brazil
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12
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Bittencourt JC. Anatomical and functional heterogeneity of 'hypothalamic' peptidergic neuron populations. Nat Rev Endocrinol 2022; 18:450. [PMID: 35469075 DOI: 10.1038/s41574-022-00680-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Jackson C Bittencourt
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil.
- Center for Neurosciences and Behaviour, Institute of Psychology, University of Sao Paulo, Sao Paulo, Brazil.
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13
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Ogawa S, Yamamoto N, Hagio H, Oka Y, Parhar IS. Multiple gonadotropin-releasing hormone systems in non-mammalian vertebrates: Ontogeny, anatomy, and physiology. J Neuroendocrinol 2022; 34:e13068. [PMID: 34931380 DOI: 10.1111/jne.13068] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 01/08/2023]
Abstract
Three paralogous genes for gonadotropin-releasing hormone (GnRH; gnrh1, gnrh2, and gnrh3) and GnRH receptors exist in non-mammalian vertebrates. However, there are some vertebrate species in which one or two of these paralogous genes have become non-functional during evolution. The developmental migration of GnRH neurons in the brain is evolutionarily conserved in mammals, reptiles, birds, amphibians, and jawed teleost fish. The three GnRH paralogs have specific expression patterns in the brain and originate from multiple sites. In acanthopterygian teleosts (medaka, cichlid, etc.), the preoptic area (POA)-GnRH1 and terminal nerve (TN)-GnRH3 neuronal types originate from the olfactory regions. In other fish species (zebrafish, goldfish and salmon) with only two GnRH paralogs (GnRH2 and GnRH3), the TN- and POA-GnRH3 neuronal types share the same olfactory origin. However, the developmental origin of midbrain (MB)-GnRH2 neurons is debatable between mesencephalic or neural crest site. Each GnRH system has distinctive anatomical and physiological characteristics, and functions differently. The POA-GnRH1 neurons are hypophysiotropic in nature and function in the neuroendocrine control of reproduction. The non-hypophysiotropic GnRH2/GnRH3 neurons probably play neuromodulatory roles in metabolism (MB-GnRH2) and the control of motivational state for sexual behavior (TN-GnRH3).
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Affiliation(s)
- Satoshi Ogawa
- Jeffrey Cheah School of Medicine & Health Sciences, Monash University Malaysia, Selangor, Malaysia
| | - Naoyuki Yamamoto
- Laboratory of Fish Biology, Department of Animal Sciences, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Hanako Hagio
- Laboratory of Fish Biology, Department of Animal Sciences, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
- Institute for Advanced Research, Nagoya University, Nagoya, Japan
| | - Yoshitaka Oka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Ishwar S Parhar
- Jeffrey Cheah School of Medicine & Health Sciences, Monash University Malaysia, Selangor, Malaysia
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14
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Watts AG, Kanoski SE, Sanchez-Watts G, Langhans W. The physiological control of eating: signals, neurons, and networks. Physiol Rev 2022; 102:689-813. [PMID: 34486393 PMCID: PMC8759974 DOI: 10.1152/physrev.00028.2020] [Citation(s) in RCA: 53] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 08/30/2021] [Indexed: 02/07/2023] Open
Abstract
During the past 30 yr, investigating the physiology of eating behaviors has generated a truly vast literature. This is fueled in part by a dramatic increase in obesity and its comorbidities that has coincided with an ever increasing sophistication of genetically based manipulations. These techniques have produced results with a remarkable degree of cell specificity, particularly at the cell signaling level, and have played a lead role in advancing the field. However, putting these findings into a brain-wide context that connects physiological signals and neurons to behavior and somatic physiology requires a thorough consideration of neuronal connections: a field that has also seen an extraordinary technological revolution. Our goal is to present a comprehensive and balanced assessment of how physiological signals associated with energy homeostasis interact at many brain levels to control eating behaviors. A major theme is that these signals engage sets of interacting neural networks throughout the brain that are defined by specific neural connections. We begin by discussing some fundamental concepts, including ones that still engender vigorous debate, that provide the necessary frameworks for understanding how the brain controls meal initiation and termination. These include key word definitions, ATP availability as the pivotal regulated variable in energy homeostasis, neuropeptide signaling, homeostatic and hedonic eating, and meal structure. Within this context, we discuss network models of how key regions in the endbrain (or telencephalon), hypothalamus, hindbrain, medulla, vagus nerve, and spinal cord work together with the gastrointestinal tract to enable the complex motor events that permit animals to eat in diverse situations.
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Affiliation(s)
- Alan G Watts
- The Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, California
| | - Scott E Kanoski
- The Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, California
| | - Graciela Sanchez-Watts
- The Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, California
| | - Wolfgang Langhans
- Physiology and Behavior Laboratory, Eidgenössische Technische Hochschule-Zürich, Schwerzenbach, Switzerland
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15
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Crosstalk between Melanin Concentrating Hormone and Endocrine Factors: Implications for Obesity. Int J Mol Sci 2022; 23:ijms23052436. [PMID: 35269579 PMCID: PMC8910548 DOI: 10.3390/ijms23052436] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 02/10/2022] [Accepted: 02/21/2022] [Indexed: 01/03/2023] Open
Abstract
Melanin-concentrating hormone (MCH) is a 19aa cyclic peptide exclusively expressed in the lateral hypothalamic area, which is an area of the brain involved in a large number of physiological functions and vital processes such as nutrient sensing, food intake, sleep-wake arousal, memory formation, and reproduction. However, the role of the lateral hypothalamic area in metabolic regulation stands out as the most relevant function. MCH regulates energy balance and glucose homeostasis by controlling food intake and peripheral lipid metabolism, energy expenditure, locomotor activity and brown adipose tissue thermogenesis. However, the MCH control of energy balance is a complex mechanism that involves the interaction of several neuroendocrine systems. The aim of the present work is to describe the current knowledge of the crosstalk of MCH with different endocrine factors. We also provide our view about the possible use of melanin-concentrating hormone receptor antagonists for the treatment of metabolic complications. In light of the data provided here and based on its actions and function, we believe that the MCH system emerges as an important target for the treatment of obesity and its comorbidities.
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16
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Hypothalamic melanin-concentrating hormone regulates hippocampus-dorsolateral septum activity. Nat Neurosci 2022; 25:61-71. [PMID: 34980924 PMCID: PMC8741735 DOI: 10.1038/s41593-021-00984-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 11/10/2021] [Indexed: 12/15/2022]
Abstract
Hypothalamic melanin-concentrating hormone (MCH) polypeptide contributes to regulating energy homeostasis, sleep, and memory, though the mechanistic bases of its effects are unknown. Here, in mice, we uncover the physiological mechanism underlying the functional role of MCH signaling in projections to the dorsolateral septum (dLS), a region involved in routing hippocampal firing rhythms and encoding spatial memory based on such rhythms. Firing activity within the dLS in response to dorsal CA3 (dCA3) excitation is limited by strong feed-forward inhibition (FFI). We find that MCH synchronizes dLS neuronal firing with its dCA3 inputs by enhancing GABA release, which subsequently reduces the FFI and augments dCA3 excitatory input strength, both via presynaptic mechanisms. At the functional level, our data reveal a role for MCH signaling in the dLS in facilitating spatial memory. These findings support a model in which peptidergic signaling within the dLS modulates dorsal hippocampal output and supports memory encoding.
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17
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Al-Massadi O, Dieguez C, Schneeberger M, López M, Schwaninger M, Prevot V, Nogueiras R. Multifaceted actions of melanin-concentrating hormone on mammalian energy homeostasis. Nat Rev Endocrinol 2021; 17:745-755. [PMID: 34608277 DOI: 10.1038/s41574-021-00559-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/16/2021] [Indexed: 12/12/2022]
Abstract
Melanin-concentrating hormone (MCH) is a small cyclic peptide expressed in all mammals, mainly in the hypothalamus. MCH acts as a robust integrator of several physiological functions and has crucial roles in the regulation of sleep-wake rhythms, feeding behaviour and metabolism. MCH signalling has a very broad endocrine context and is involved in physiological functions and emotional states associated with metabolism, such as reproduction, anxiety, depression, sleep and circadian rhythms. MCH mediates its functions through two receptors (MCHR1 and MCHR2), of which only MCHR1 is common to all mammals. Owing to the wide variety of MCH downstream signalling pathways, MCHR1 agonists and antagonists have great potential as tools for the directed management of energy balance disorders and associated metabolic complications, and translational strategies using these compounds hold promise for the development of novel treatments for obesity. This Review provides an overview of the numerous roles of MCH in energy and glucose homeostasis, as well as in regulation of the mesolimbic dopaminergic circuits that encode the hedonic component of food intake.
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Affiliation(s)
- Omar Al-Massadi
- Instituto de Investigación Sanitaria de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS/SERGAS), Santiago de Compostela, Spain.
- CIBER Fisiopatologia de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, Spain.
| | - Carlos Dieguez
- CIBER Fisiopatologia de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, Spain
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
| | - Marc Schneeberger
- Laboratory of Molecular Genetics, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| | - Miguel López
- CIBER Fisiopatologia de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, Spain
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
| | - Markus Schwaninger
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Vincent Prevot
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience and Cognition, Laboratory of Development and Plasticity of the Neuroendocrine Brain, UMR-S1172, EGID, Lille, France
| | - Ruben Nogueiras
- CIBER Fisiopatologia de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, Spain.
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain.
- Galician Agency of Innovation (GAIN), Xunta de Galicia, Santiago de Compostela, Spain.
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18
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Peleg-Raibstein D, Burdakov D. Do orexin/hypocretin neurons signal stress or reward? Peptides 2021; 145:170629. [PMID: 34416308 DOI: 10.1016/j.peptides.2021.170629] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/04/2021] [Accepted: 08/14/2021] [Indexed: 12/23/2022]
Abstract
Hypothalamic neurons that produce the peptide transmitters orexins/hypocretins (HONs) broadcast their predominantly neuroexcitatory outputs to the entire brain via their extremely wide axonal projections. HONs were originally reported to be activated by food deprivation, and to stimulate arousal, energy expenditure, and eating. This led to extensive studies of HONs in the context of nutrient-sensing and energy balance control. While activation of HONs by body energy depletion continues to be supported by experimental evidence, it has also become clear that HONs are robustly activated not only by nutrient depletion, but also by diverse sensory stimuli (both neutral and those associated with rewarding or aversive events), seemingly unrelated to each other or to energy balance. One theory that could unify these findings is that all these stimuli signal "stress" - defined either as a potentially harmful state, or an awareness of reward deficiency. If HON activity is conceptualized as a cumulative representation of stress, then many of the reported HONs outputs - including EEG arousal, sympathetic activation, place avoidance, and exploratory behaviours - could be viewed as logical stress-counteracting responses. We discuss evidence for and against this unifying theory of HON function, including the alterations in HON activity observed in anxiety and depression disorders. We propose that, in order to orchestrate stress-countering responses, HONs need to coactivate motivation and aversion brain systems, and the impact of HON stimulation on affective states may be perceived as rewarding or aversive depending on the baseline HON activity.
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Affiliation(s)
| | - Denis Burdakov
- Department of Health Sciences and Technology, ETH Zürich, Switzerland.
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19
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Barbier M, González JA, Houdayer C, Burdakov D, Risold P, Croizier S. Projections from the dorsomedial division of the bed nucleus of the stria terminalis to hypothalamic nuclei in the mouse. J Comp Neurol 2021; 529:929-956. [PMID: 32678476 PMCID: PMC7891577 DOI: 10.1002/cne.24988] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/30/2020] [Accepted: 07/14/2020] [Indexed: 12/18/2022]
Abstract
As stressful environment is a potent modulator of feeding, we seek in the present work to decipher the neuroanatomical basis for an interplay between stress and feeding behaviors. For this, we combined anterograde and retrograde tracing with immunohistochemical approaches to investigate the patterns of projections between the dorsomedial division of the bed nucleus of the stria terminalis (BNST), well connected to the amygdala, and hypothalamic structures such as the paraventricular (PVH) and dorsomedial (DMH), the arcuate (ARH) nuclei and the lateral hypothalamic areas (LHA) known to control feeding and motivated behaviors. We particularly focused our study on afferences to proopiomelanocortin (POMC), agouti-related peptide (AgRP), melanin-concentrating-hormone (MCH) and orexin (ORX) neurons characteristics of the ARH and the LHA, respectively. We found light to intense innervation of all these hypothalamic nuclei. We particularly showed an innervation of POMC, AgRP, MCH and ORX neurons by the dorsomedial and dorsolateral divisions of the BNST. Therefore, these results lay the foundation for a better understanding of the neuroanatomical basis of the stress-related feeding behaviors.
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Affiliation(s)
- Marie Barbier
- EA481, Neurosciences Intégratives et Cliniques, UFR SantéUniversité Bourgogne Franche‐ComtéBesançonFrance
- Department of PsychiatrySeaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - J. Antonio González
- The Francis Crick InstituteLondonUK
- The Rowett Institute, School of MedicineMedical Sciences and Nutrition, University of AberdeenAberdeenUK
| | - Christophe Houdayer
- EA481, Neurosciences Intégratives et Cliniques, UFR SantéUniversité Bourgogne Franche‐ComtéBesançonFrance
| | - Denis Burdakov
- The Francis Crick InstituteLondonUK
- Neurobehavioural Dynamics Lab, Institute for Neuroscience, D‐HESTSwiss Federal Institute of Technology / ETH ZürichZürichSwitzerland
| | - Pierre‐Yves Risold
- EA481, Neurosciences Intégratives et Cliniques, UFR SantéUniversité Bourgogne Franche‐ComtéBesançonFrance
| | - Sophie Croizier
- University of LausanneCenter for Integrative GenomicsLausanneSwitzerland
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20
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Concetti C, Burdakov D. Orexin/Hypocretin and MCH Neurons: Cognitive and Motor Roles Beyond Arousal. Front Neurosci 2021; 15:639313. [PMID: 33828450 PMCID: PMC8019792 DOI: 10.3389/fnins.2021.639313] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 03/01/2021] [Indexed: 02/01/2023] Open
Abstract
The lateral hypothalamus (LH) is classically implicated in sleep-wake control. It is the main source of orexin/hypocretin and melanin-concentrating hormone (MCH) neuropeptides in the brain, which have been both implicated in arousal state switching. These neuropeptides are produced by non-overlapping LH neurons, which both project widely throughout the brain, where release of orexin and MCH activates specific postsynaptic G-protein-coupled receptors. Optogenetic manipulations of orexin and MCH neurons during sleep indicate that they promote awakening and REM sleep, respectively. However, recordings from orexin and MCH neurons in awake, moving animals suggest that they also act outside sleep/wake switching. Here, we review recent studies showing that both orexin and MCH neurons can rapidly (sub-second-timescale) change their firing when awake animals experience external stimuli, or during self-paced exploration of objects and places. However, the sensory-behavioral correlates of orexin and MCH neural activation can be quite different. Orexin neurons are generally more dynamic, with about 2/3rds of them activated before and during self-initiated running, and most activated by sensory stimulation across sensory modalities. MCH neurons are activated in a more select manner, for example upon self-paced investigation of novel objects and by certain other novel stimuli. We discuss optogenetic and chemogenetic manipulations of orexin and MCH neurons, which combined with pharmacological blockade of orexin and MCH receptors, imply that these rapid LH dynamics shape fundamental cognitive and motor processes due to orexin and MCH neuropeptide actions in the awake brain. Finally, we contemplate whether the awake control of psychomotor brain functions by orexin and MCH are distinct from their “arousal” effects.
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Affiliation(s)
- Cristina Concetti
- Department of Health Sciences and Technology, ETH Zürich, Zurich, Switzerland
| | - Denis Burdakov
- Department of Health Sciences and Technology, ETH Zürich, Zurich, Switzerland
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21
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Guillaumin MCC, Burdakov D. Neuropeptides as Primary Mediators of Brain Circuit Connectivity. Front Neurosci 2021; 15:644313. [PMID: 33776641 PMCID: PMC7991401 DOI: 10.3389/fnins.2021.644313] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 02/18/2021] [Indexed: 11/21/2022] Open
Abstract
Across sleep and wakefulness, brain function requires inter-neuronal interactions lasting beyond seconds. Yet, most studies of neural circuit connectivity focus on millisecond-scale interactions mediated by the classic fast transmitters, GABA and glutamate. In contrast, neural circuit roles of the largest transmitter family in the brain–the slow-acting peptide transmitters–remain relatively overlooked, or described as “modulatory.” Neuropeptides may efficiently implement sustained neural circuit connectivity, since they are not rapidly removed from the extracellular space, and their prolonged action does not require continuous presynaptic firing. From this perspective, we review actions of evolutionarily-conserved neuropeptides made by brain-wide-projecting hypothalamic neurons, focusing on lateral hypothalamus (LH) neuropeptides essential for stable consciousness: the orexins/hypocretins. Action potential-dependent orexin release inside and outside the hypothalamus evokes slow postsynaptic excitation. This excitation does not arise from modulation of classic neurotransmission, but involves direct action of orexins on their specific G-protein coupled receptors (GPCRs) coupled to ion channels. While millisecond-scale, GABA/glutamate connectivity within the LH may not be strong, re-assessing LH microcircuits from the peptidergic viewpoint is consistent with slow local microcircuits. The sustained actions of neuropeptides on neuronal membrane potential may enable core brain functions, such as temporal integration and the creation of lasting permissive signals that act as “eligibility traces” for context-dependent information routing and plasticity. The slowness of neuropeptides has unique advantages for efficient neuronal processing and feedback control of consciousness.
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Affiliation(s)
| | - Denis Burdakov
- Department of Health Sciences and Technology, ETH Zürich, Zurich, Switzerland
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22
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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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23
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Ogawa S, Pfaff DW, Parhar IS. Fish as a model in social neuroscience: conservation and diversity in the social brain network. Biol Rev Camb Philos Soc 2021; 96:999-1020. [PMID: 33559323 DOI: 10.1111/brv.12689] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 01/19/2021] [Accepted: 01/20/2021] [Indexed: 12/21/2022]
Abstract
Mechanisms for fish social behaviours involve a social brain network (SBN) which is evolutionarily conserved among vertebrates. However, considerable diversity is observed in the actual behaviour patterns amongst nearly 30000 fish species. The huge variation found in socio-sexual behaviours and strategies is likely generated by a morphologically and genetically well-conserved small forebrain system. Hence, teleost fish provide a useful model to study the fundamental mechanisms underlying social brain functions. Herein we review the foundations underlying fish social behaviours including sensory, hormonal, molecular and neuroanatomical features. Gonadotropin-releasing hormone neurons clearly play important roles, but the participation of vasotocin and isotocin is also highlighted. Genetic investigations of developing fish brain have revealed the molecular complexity of neural development of the SBN. In addition to straightforward social behaviours such as sex and aggression, new experiments have revealed higher order and unique phenomena such as social eavesdropping and social buffering in fish. Finally, observations interpreted as 'collective cognition' in fish can likely be explained by careful observation of sensory determinants and analyses using the dynamics of quantitative scaling. Understanding of the functions of the SBN in fish provide clues for understanding the origin and evolution of higher social functions in vertebrates.
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Affiliation(s)
- Satoshi Ogawa
- Brain Research Institute, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor, 47500, Malaysia
| | - Donald W Pfaff
- Laboratory of Neurobiology and Behavior, Rockefeller University, New York, NY, 10065, U.S.A
| | - Ishwar S Parhar
- Brain Research Institute, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor, 47500, Malaysia
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24
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Philippe C, Klebermass EM, Balber T, Kulterer OC, Zeilinger M, Egger G, Dumanic M, Herz CT, Kiefer FW, Scheuba C, Scherer T, Fürnsinn C, Vraka C, Pallitsch K, Spreitzer H, Wadsak W, Viernstein H, Hacker M, Mitterhauser M. Discovery of melanin-concentrating hormone receptor 1 in brown adipose tissue. Ann N Y Acad Sci 2021; 1494:70-86. [PMID: 33502798 PMCID: PMC8248337 DOI: 10.1111/nyas.14563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/23/2020] [Accepted: 12/23/2020] [Indexed: 11/26/2022]
Abstract
Although extensive research on brown adipose tissue (BAT) has stimulated optimism in the battle against obesity and diabetes, BAT physiology and organ crosstalk are not fully understood. Besides BAT, melanin‐concentrating hormone (MCH) and its receptor (MCHR1) play an important role in energy homeostasis. Because of the link between hypothalamic MCH neurons and sympathetic BAT activation via β‐adrenoceptors, we investigated the expression and physiological role of the MCHR1 in BAT. MCHR1 was detected in rodent and human BAT with RT‐qPCR and western blot analyses. In vivo imaging in rats used the glucose analog [18F]FDG and the MCHR1‐tracer [11C]SNAP‐7941. We found that the β3‐adrenoceptor (ADRB3) agonist CL316,243 increased [11C]SNAP‐7941 uptake in BAT. Additionally, a pharmacological concentration of SNAP‐7941—a low‐affinity ADRB3 ligand—stimulated [18F]FDG uptake, reflecting BAT activation. In cultured human adipocytes, CL316,243 induced MCHR1 expression, further supporting a direct interaction between MCHR1 and ADRB3. These findings characterized MCHR1 expression in rodent and human BAT for the first time, including in vitro and in vivo data demonstrating a link between MCHR1 and the β3‐adrenergic system. The presence of MCHR1 in BAT emphasizes the role of BAT in energy homeostasis and may help uncover treatment approaches for obesity.
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Affiliation(s)
- Cécile Philippe
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.,Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria
| | - Eva-Maria Klebermass
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.,Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria
| | - Theresa Balber
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.,Ludwig Boltzmann Institute Applied Diagnostics, Vienna, Austria
| | - Oana C Kulterer
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.,Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Markus Zeilinger
- Faculty of Engineering, University of Applied Sciences Wiener Neustadt, Wiener Neustadt, Austria
| | - Gerda Egger
- Ludwig Boltzmann Institute Applied Diagnostics, Vienna, Austria.,Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - Monika Dumanic
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Carsten T Herz
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Florian W Kiefer
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Christian Scheuba
- Division of General Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Thomas Scherer
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Clemens Fürnsinn
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Chrysoula Vraka
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | | | - Helmut Spreitzer
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Wolfgang Wadsak
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.,Center for Biomarker Research in Medicine - CBmed GmbH, Graz, Austria
| | - Helmut Viernstein
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria
| | - Marcus Hacker
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Markus Mitterhauser
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.,Ludwig Boltzmann Institute Applied Diagnostics, Vienna, Austria
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Lee J, Raycraft L, Johnson AW. The dynamic regulation of appetitive behavior through lateral hypothalamic orexin and melanin concentrating hormone expressing cells. Physiol Behav 2020; 229:113234. [PMID: 33130035 DOI: 10.1016/j.physbeh.2020.113234] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 02/07/2023]
Abstract
The lateral hypothalamic area (LHA) is a heterogeneous brain structure extensively studied for its potent role in regulating energy balance. The anatomical and molecular diversity of the LHA permits the orchestration of responses to energy sensing cues from the brain and periphery. Two of the primary cell populations within the LHA associated with integration of this information are Orexin (ORX) and Melanin Concentrating Hormone (MCH). While both of these non-overlapping populations exhibit orexigenic properties, the activities of these two systems support feeding behavior through contrasting mechanisms. We describe the anatomical and functional properties as well as interaction with other neuropeptides and brain reward and hedonic systems. Specific outputs relating to arousal, food seeking, feeding, and metabolism are coordinated through these mechanisms. We then discuss how both the ORX and MCH systems harmonize in a divergent yet overall cooperative manner to orchestrate feeding behavior through transitions between various appetitive states, and thus offer novel insights into LHA allostatic control of appetite.
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Affiliation(s)
| | | | - Alexander W Johnson
- Department of Psychology; Neuroscience Program, Michigan State University, East Lansing.
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26
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Bandaru SS, Khanday MA, Ibrahim N, Naganuma F, Vetrivelan R. Sleep-Wake Control by Melanin-Concentrating Hormone (MCH) Neurons: a Review of Recent Findings. Curr Neurol Neurosci Rep 2020; 20:55. [PMID: 33006677 DOI: 10.1007/s11910-020-01075-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/17/2020] [Indexed: 12/14/2022]
Abstract
PURPOSE OF THE REVIEW Melanin-concentrating hormone (MCH)-expressing neurons located in the lateral hypothalamus are considered as an integral component of sleep-wake circuitry. However, the precise role of MCH neurons in sleep-wake regulation has remained unclear, despite several years of research employing a wide range of techniques. We review recent data on this aspect, which are mostly inconsistent, and propose a novel role for MCH neurons in sleep regulation. RECENT FINDINGS While almost all studies using "gain-of-function" approaches show an increase in rapid eye movement sleep (or paradoxical sleep; PS), loss-of-function approaches have not shown reductions in PS. Similarly, the reported changes in wakefulness or non-rapid eye movement sleep (slow-wave sleep; SWS) with manipulation of the MCH system using conditional genetic methods are inconsistent. Currently available data do not support a role for MCH neurons in spontaneous sleep-wake but imply a crucial role for them in orchestrating sleep-wake responses to changes in external and internal environments.
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Affiliation(s)
- Sathyajit S Bandaru
- Department of Neurology, Beth Israel Deaconess Medical Center, 3 Blackfan Circle, Center for Life Science # 711, Boston, MA, USA
| | - Mudasir A Khanday
- Department of Neurology, Beth Israel Deaconess Medical Center, 3 Blackfan Circle, Center for Life Science # 711, Boston, MA, USA.,Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
| | - Nazifa Ibrahim
- Department of Neurology, Beth Israel Deaconess Medical Center, 3 Blackfan Circle, Center for Life Science # 711, Boston, MA, USA.,Department of Public Health Sciences, University of Massachusetts, Amherst, MA, USA
| | - Fumito Naganuma
- Department of Neurology, Beth Israel Deaconess Medical Center, 3 Blackfan Circle, Center for Life Science # 711, Boston, MA, USA.,Division of Pharmacology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Ramalingam Vetrivelan
- Department of Neurology, Beth Israel Deaconess Medical Center, 3 Blackfan Circle, Center for Life Science # 711, Boston, MA, USA. .,Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA.
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27
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Burdakov D, Peleg-Raibstein D. The hypothalamus as a primary coordinator of memory updating. Physiol Behav 2020; 223:112988. [DOI: 10.1016/j.physbeh.2020.112988] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 05/05/2020] [Accepted: 05/26/2020] [Indexed: 12/19/2022]
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28
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Control of fear extinction by hypothalamic melanin-concentrating hormone-expressing neurons. Proc Natl Acad Sci U S A 2020; 117:22514-22521. [PMID: 32848057 PMCID: PMC7486764 DOI: 10.1073/pnas.2007993117] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Learning to fear danger is essential for survival. However, overactive, relapsing fear behavior in the absence of danger is a hallmark of disabling anxiety disorders that affect millions of people. Its suppression is thus of great interest, but the necessary brain components remain incompletely identified. We studied fear suppression through a procedure in which, after acquiring fear of aversive events (fear learning), subjects were exposed to fear-eliciting cues without aversive events (safety learning), leading to suppression of fear behavior (fear extinction). Here we show that inappropriate, learning-resistant fear behavior results from disruption of brain components not previously implicated in this disorder: hypothalamic melanin-concentrating hormone-expressing neurons (MNs). Using real-time recordings of MNs across fear learning and extinction, we provide evidence that fear-inducing aversive events elevate MN activity. We find that optogenetic disruption of this MN activity profoundly impairs safety learning, abnormally slowing down fear extinction and exacerbating fear relapse. Importantly, we demonstrate that the MN disruption impairs neither fear learning nor related sensory responses, indicating that MNs differentially control safety and fear learning. Thus, we identify a neural substrate for inhibition of excessive fear behavior.
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30
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MCH Neurons Regulate Permeability of the Median Eminence Barrier. Neuron 2020; 107:306-319.e9. [PMID: 32407670 PMCID: PMC7383232 DOI: 10.1016/j.neuron.2020.04.020] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 03/06/2020] [Accepted: 04/20/2020] [Indexed: 01/17/2023]
Abstract
Melanin-concentrating hormone (MCH)-expressing neurons are key regulators of energy and glucose homeostasis. Here, we demonstrate that they provide dense projections to the median eminence (ME) in close proximity to tanycytes and fenestrated vessels. Chemogenetic activation of MCH neurons as well as optogenetic stimulation of their projections in the ME enhance permeability of the ME by increasing fenestrated vascular loops and enhance leptin action in the arcuate nucleus of the hypothalamus (ARC). Unbiased phosphoRiboTrap-based assessment of cell activation upon chemogenetic MCH neuron activation reveals MCH-neuron-dependent regulation of endothelial cells. MCH neurons express the vascular endothelial growth factor A (VEGFA), and blocking VEGF-R signaling attenuates the leptin-sensitizing effect of MCH neuron activation. Our experiments reveal that MCH neurons directly regulate permeability of the ME barrier, linking the activity of energy state and sleep regulatory neurons to the regulation of hormone accessibility to the ARC. MCH neurons provide dense projections to the median eminence MCH neuron activation promotes permeability of the median eminence barrier MCH neuron activation enhances microvessel fenestration in the ME MCH neuron activation enhances leptin action in the arcuate nucleus
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31
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Vasquez JH, Borniger JC. Neuroendocrine and Behavioral Consequences of Hyperglycemia in Cancer. Endocrinology 2020; 161:5810322. [PMID: 32193527 PMCID: PMC7174055 DOI: 10.1210/endocr/bqaa047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Accepted: 03/16/2020] [Indexed: 12/20/2022]
Abstract
A hallmark of cancer is the disruption of cellular metabolism during the course of malignant growth. Major focus is now on how these cell-autonomous processes propagate to the tumor microenvironment and, more generally, to the entire host system. This chain of events can have major consequences for a patient's health and wellbeing. For example, metabolic "waste" produced by cancer cells activates systemic inflammatory responses, which can interfere with hepatic insulin receptor signaling and glucose homeostasis. Research is just now beginning to understand how these processes occur, and how they contribute to systemic symptoms prevalent across cancers, including hyperglycemia, fatigue, pain, and sleep disruption. Indeed, it is only recently that we have begun to appreciate that the brain does not play a passive role in responding to cancer-induced changes in physiology. In this review, we provide a brief discussion of how oncogene-directed metabolic reprogramming disrupts host metabolism, with a specific emphasis on cancer-induced hyperglycemia. We further discuss how the brain senses circulating glucose concentrations and how this process goes awry as a response to distant neoplastic growth. Finally, as glucose-sensing neurons control diverse aspects of physiology and behavior, we link cancer-induced changes in energy balance to neuroendocrine and behavioral consequences for the host organism.
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Affiliation(s)
- Juan H Vasquez
- Department of Biology, University of Texas – San Antonio, San Antonio, Texas
| | - Jeremy C Borniger
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York
- Correspondence: Jeremy C. Borniger, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724. E-mail:
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32
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Linehan V, Fang LZ, Parsons MP, Hirasawa M. High-fat diet induces time-dependent synaptic plasticity of the lateral hypothalamus. Mol Metab 2020; 36:100977. [PMID: 32277924 PMCID: PMC7170999 DOI: 10.1016/j.molmet.2020.100977] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 02/28/2020] [Accepted: 03/10/2020] [Indexed: 11/15/2022] Open
Abstract
Objective Orexin (ORX) and melanin-concentrating hormone (MCH) neurons in the lateral hypothalamus are critical regulators of energy homeostasis and are thought to differentially contribute to diet-induced obesity. However, it is unclear whether the synaptic properties of these cells are altered by obesogenic diets over time. Methods Rats and mice were fed a control chow or palatable high-fat diet (HFD) for various durations and then synaptic properties of ORX and MCH neurons were examined using exvivo whole-cell patch clamp recording. Confocal imaging was performed to assess the number of excitatory synaptic contacts to these neurons. Results ORX neurons exhibited a transient increase in spontaneous excitatory transmission as early as 1 day up to 1 week of HFD, which returned to control levels with prolonged feeding. Conversely, HFD induced a delayed increase in excitatory synaptic transmission to MCH neurons, which progressively increased as HFD became chronic. This increase occurred before the onset of significant weight gain. These synaptic changes appeared to be due to altered postsynaptic sensitivity or the number of active synaptic contacts depending on cell type and feeding duration. However, HFD induced no change in inhibitory transmission in either cell type at any time point. Conclusions These results suggest that the effects of HFD on feeding-related neurons are cell type-specific and dynamic. This highlights the importance of considering the feeding duration for research and weight loss interventions. ORX neurons may contribute to early hyperphagia, whereas MCH neurons may play a role in the onset and long-term maintenance of diet-induced obesity. High-fat diet increases excitatory transmission to orexin and MCH neurons. Increased excitatory drive to orexin neurons occurs within the first week but is transient. Excitatory synapses to MCH neurons increase with prolonged high-fat diet. Excitatory changes in MCH neurons are delayed but precede significant weight gain. These synaptic changes may contribute to the development and the maintenance of obesity.
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Affiliation(s)
- Victoria Linehan
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, St. John's, Newfoundland, A1B 3V6, Canada
| | - Lisa Z Fang
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, St. John's, Newfoundland, A1B 3V6, Canada
| | - Matthew P Parsons
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, St. John's, Newfoundland, A1B 3V6, Canada
| | - Michiru Hirasawa
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, St. John's, Newfoundland, A1B 3V6, Canada.
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33
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Regan MD, Flynn-Evans EE, Griko YV, Kilduff TS, Rittenberger JC, Ruskin KJ, Buck CL. Shallow metabolic depression and human spaceflight: a feasible first step. J Appl Physiol (1985) 2020; 128:637-647. [PMID: 31999524 DOI: 10.1152/japplphysiol.00725.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Synthetic torpor is an induced state of deep metabolic depression (MD) in an organism that does not naturally employ regulated and reversible MD. If applied to spaceflight crewmembers, this metabolic state may theoretically mitigate numerous biological and logistical challenges of human spaceflight. These benefits have been the focus of numerous recent articles where, invariably, they are discussed in the context of hypothetical deep MD states in which the metabolism of crewmembers is profoundly depressed relative to basal rates. However, inducing these deep MD states in humans, particularly humans aboard spacecraft, is currently impossible. Here, we discuss shallow MD as a feasible first step toward synthetic torpor during spaceflight and summarize perspectives following a recent NASA-hosted workshop. We discuss methods to safely induce shallow MD (e.g., sleep and slow wave enhancement via acoustic and photoperiod stimulation; moderate sedation via dexmedetomidine), which we define as an ~20% depression of metabolic rate relative to basal levels. We also discuss different modes of shallow MD application (e.g., habitual versus targeted, whereby shallow MD is induced routinely throughout a mission or only under certain circumstances, respectively) and different spaceflight scenarios that would benefit from its use. Finally, we propose a multistep development plan toward the application of synthetic torpor to human spaceflight, highlighting shallow MD's role. As space agencies develop missions to send humans further into space than ever before, shallow MD has the potential to confer health benefits for crewmembers, reduce demands on spacecraft capacities, and serve as a testbed for deeper MD technologies.
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Affiliation(s)
- Matthew D Regan
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin
| | - Erin E Flynn-Evans
- Fatigue Countermeasures Laboratory, Human Systems Integration Division, NASA Ames Research Center, Moffett Field, California
| | - Yuri V Griko
- Countermeasure Development Laboratory, Space Biosciences Division, NASA Ames Research Center, Moffett Field, California
| | - Thomas S Kilduff
- Biosciences Division, Center for Neuroscience, SRI International, Menlo Park, California
| | - Jon C Rittenberger
- Guthrie Robert Packer Hospital Emergency Medicine Program, Geisinger Commonwealth School of Medicine, Scranton, Pennsylvania
| | - Keith J Ruskin
- Department of Anesthesia and Critical Care, University of Chicago, Chicago, Illinois
| | - C Loren Buck
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
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34
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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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The role of co-neurotransmitters in sleep and wake regulation. Mol Psychiatry 2019; 24:1284-1295. [PMID: 30377299 PMCID: PMC6491268 DOI: 10.1038/s41380-018-0291-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 09/17/2018] [Accepted: 10/08/2018] [Indexed: 12/11/2022]
Abstract
Sleep and wakefulness control in the mammalian brain requires the coordination of various discrete interconnected neurons. According to the most conventional sleep model, wake-promoting neurons (WPNs) and sleep-promoting neurons (SPNs) compete for network dominance, creating a systematic "switch" that results in either the sleep or awake state. WPNs and SPNs are ubiquitous in the brainstem and diencephalon, areas that together contain <1% of the neurons in the human brain. Interestingly, many of these WPNs and SPNs co-express and co-release various types of the neurotransmitters that often have opposing modulatory effects on the network. Co-transmission is often beneficial to structures with limited numbers of neurons because it provides increasing computational capability and flexibility. Moreover, co-transmission allows subcortical structures to bi-directionally control postsynaptic neurons, thus helping to orchestrate several complex physiological functions such as sleep. Here, we present an in-depth review of co-transmission in hypothalamic WPNs and SPNs and discuss its functional significance in the sleep-wake network.
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36
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Urbanavicius J, Fabius S, Roncalho A, Joca S, Torterolo P, Scorza C. Melanin-concentrating hormone in the Locus Coeruleus aggravates helpless behavior in stressed rats. Behav Brain Res 2019; 374:112120. [PMID: 31376444 DOI: 10.1016/j.bbr.2019.112120] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 07/17/2019] [Accepted: 07/30/2019] [Indexed: 10/26/2022]
Abstract
Animal studies have shown that antagonists of receptor 1 of Melanin-Concentrating Hormone (MCH-R1) elicit antidepressive-like behavior, suggesting that MCH-R1 might be a novel target for the treatment of depression and supports the hypothesis that MCHergic signaling regulates depressive-like behaviors. Consistent with the evidence that MCHergic neurons send projections to dorsal and median raphe nuclei, we have previously demonstrated that MCH microinjections in both nuclei induced a depressive-like behavior. Even though MCH neurons also project to Locus Coeruleus (LC), only a few studies have reported the behavioral and neurochemical effect of MCH into the LC. We studied the effects of MCH (100 and 200 ng) into the LC on coping-stress related behaviors associated with depression, using two different behavioral tests: the forced swimming test (FST) and the learned helplessness (LH). To characterize the functional interaction between MCH and the noradrenergic LC system, we also evaluated the neurochemical effects of MCH (100 ng) on the extracellular levels of noradrenaline (NA) in the medial prefrontal cortex (mPFC), an important LC terminal region involved in emotional processing. MCH administration into the LC elicited a depressive-like behavior evidenced in both paradigms. Interestingly, in the LH, MCH (100) elicited a significant increase in escape failures only in stressed animals. A significant decrease in prefrontal levels of NA was observed after MCH microinjection into the LC. Our results demonstrate that increased MCH signaling into the LC triggers depressive-like behaviors, especially in stressed animals. These data further corroborate the important role of MCH in the neurobiology of depression.
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Affiliation(s)
- Jessika Urbanavicius
- Departament of Experimental Neuropharmacology, Instituto de Investigaciones Biológicas Clemente Estable, Uruguay
| | - Sara Fabius
- Departament of Experimental Neuropharmacology, Instituto de Investigaciones Biológicas Clemente Estable, Uruguay
| | - Aline Roncalho
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Samia Joca
- Department of Physics and Chemistry, School of Pharmaceutical Sciences, University of São Paulo, Ribeirão Preto, Brazil
| | - Pablo Torterolo
- Department of Physiology, School of Medicine, Universidad de la República, Montevideo, Uruguay
| | - Cecilia Scorza
- Departament of Experimental Neuropharmacology, Instituto de Investigaciones Biológicas Clemente Estable, Uruguay.
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Niño-Rivero S, Torterolo P, Lagos P. Melanin-concentrating hormone receptor-1 is located in primary cilia of the dorsal raphe neurons. J Chem Neuroanat 2019; 98:55-62. [DOI: 10.1016/j.jchemneu.2019.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 02/25/2019] [Accepted: 03/22/2019] [Indexed: 12/19/2022]
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Kosse C, Burdakov D. Natural hypothalamic circuit dynamics underlying object memorization. Nat Commun 2019; 10:2505. [PMID: 31175285 PMCID: PMC6555780 DOI: 10.1038/s41467-019-10484-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 05/08/2019] [Indexed: 12/23/2022] Open
Abstract
Brain signals that govern memory formation remain incompletely identified. The hypothalamus is implicated in memory disorders, but how its rapidly changing activity shapes memorization is unknown. During encounters with objects, hypothalamic melanin-concentrating hormone (MCH) neurons emit brief signals that reflect object novelty. Here we show that targeted optogenetic silencing of these signals, performed selectively during the initial object encounters (i.e. memory acquisition), prevents future recognition of the objects. We identify an upstream inhibitory microcircuit from hypothalamic GAD65 neurons to MCH neurons, which constrains the memory-promoting MCH cell bursts. Finally, we demonstrate that silencing the GAD65 cells during object memory acquisition improves future object recognition through MCH-receptor-dependent pathways. These results provide causal evidence that object-associated signals in genetically distinct but interconnected hypothalamic neurons differentially control whether the brain forms object memories. This gating of memory formation by hypothalamic activity establishes appropriate behavioral responses to novel and familiar objects.
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Affiliation(s)
- Christin Kosse
- The Francis Crick Institute, London, NW1 1AT, UK
- Laboratory of Molecular Genetics, The Rockefeller University, New York, NY, 10065, USA
| | - Denis Burdakov
- The Francis Crick Institute, London, NW1 1AT, UK.
- Neurobehavioural Dynamics Lab, Institute for Neuroscience, D-HEST, Swiss Federal Institute of Technology / ETH Zürich, Zürich, 8603, Switzerland.
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Philippe C, Zeilinger M, Dumanic M, Pichler F, Fetty L, Vraka C, Balber T, Wadsak W, Pallitsch K, Spreitzer H, Lanzenberger R, Hacker M, Mitterhauser M. SNAPshots of the MCHR1: a Comparison Between the PET-Tracers [ 18F]FE@SNAP and [ 11C]SNAP-7941. Mol Imaging Biol 2019; 21:257-268. [PMID: 29948643 PMCID: PMC6449294 DOI: 10.1007/s11307-018-1212-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PURPOSE The melanin-concentrating hormone receptor 1 (MCHR1) has become an important pharmacological target, since it may be involved in various diseases, such as diabetes, insulin resistance, and obesity. Hence, a suitable positron emission tomography radiotracer for the in vivo assessment of the MCHR1 pharmacology is imperative. The current paper contrasts the extensive in vitro, in vivo, and ex vivo assessments of the radiotracers [18F]FE@SNAP and [11C]SNAP-7941 and provides comprehensive information about their biological and physicochemical properties. Furthermore, it examines their suitability for first-in-man imaging studies. PROCEDURES Kinetic real-time cell-binding studies with [18F]FE@SNAP and [11C]SNAP-7941 were conducted on adherent Chines hamster ovary (CHO-K1) cells stably expressing the human MCHR1 and MCHR2. Small animal imaging studies on mice and rats were performed under displacement and baseline conditions, as well as after pretreatment with the P-glycoprotein/breast cancer resistant protein inhibitor tariquidar. After the imaging studies, detailed analyses of the ex vivo biodistribution were performed. Ex vivo metabolism was determined in rat blood and brain and analyzed at various time points using a quantitative radio-HPLC assay. RESULTS [11C]SNAP-7941 demonstrates high uptake on CHO-K1-hMCHR1 cells, whereas no uptake was detected for the CHO-K1-hMCHR2 cells. In contrast, [18F]FE@SNAP evinced binding to CHO-K1-hMCHR1 and CHO-K1-hMCHR2 cells. Imaging studies with [18F]FE@SNAP and [11C]SNAP-7941 showed an increased brain uptake after tariquidar pretreatment in mice, as well as in rats, and exhibited a significant difference between the time-activity curves of the baseline and blocking groups. Biodistribution of both tracers demonstrated a decreased uptake after displacement. [11C]SNAP-7941 revealed a high metabolic stability in rats, whereas [18F]FE@SNAP was rapidly metabolized. CONCLUSIONS Both radiotracers demonstrate appropriate imaging properties for the MCHR1. However, the pronounced metabolic stability as well as superior selectivity and affinity of [11C]SNAP-7941 underlines the decisive superiority over [18F]FE@SNAP.
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Affiliation(s)
- Cécile Philippe
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria
| | - Markus Zeilinger
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Faculty of Engineering, University of Applied Sciences Wiener Neustadt, Neustadt, Austria
| | - Monika Dumanic
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Florian Pichler
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Faculty of Engineering, University of Applied Sciences Wiener Neustadt, Neustadt, Austria
| | - Lukas Fetty
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Department of Radiotherapy, Division of Medical Physics, Medical University of Vienna, Vienna, Austria
| | - Chrysoula Vraka
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Theresa Balber
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Wolfgang Wadsak
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Department of Inorganic Chemistry, University of Vienna, Vienna, Austria
- CBmed, Graz, Austria
| | | | - Helmut Spreitzer
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Marcus Hacker
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Markus Mitterhauser
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria.
- Ludwig Boltzmann Institute Applied Diagnostics, Vienna, Austria.
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Ayala C, Pennacchio GE, Soaje M, Bittencourt JC, Celis ME, Jahn GA, Valdez SR, Seltzer AM. Differential effects of hypo- and hyperthyroidism on remodeling of contacts between neurons expressing the neuropeptide EI and tyrosine hydroxylase in hypothalamic areas of the male rat. Peptides 2019; 113:1-10. [PMID: 30590076 DOI: 10.1016/j.peptides.2018.12.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 12/10/2018] [Accepted: 12/22/2018] [Indexed: 12/11/2022]
Abstract
The Neuropeptide EI (NEI, glutamic acid- isoleucine amide) participates in neuroendocrine function. Previously we demonstrated that NEI concentration is regulated by thyroid hormones in discrete hypothalamic areas in rats. We observed that the thyroid status affects the dopaminergic regulation of the pituitary hormones. In this study we explored possible interactions between NEI and tyrosine hydroxylase (TH) containing elements in selected hypothalamic areas of male rats. Neuronal somas, terminals and boutons were assessed by confocal microscopy, in hypo- and hyperthyroid animals. We observed a remodeling of the contacts between the TH and NEI immunoreactive elements in the incerto-hypothalamic area (IHy, also known as rostromedial zona incerta) according to thyroid function. However, in the dorsolateral zone of the peduncular part of the lateral hypothalamus (DL-PLH) the thyroid hormones affect the dendritic trees of the neurons without perturbing the overall NEI/TH contacts. Also, we demonstrated that TRH Receptor 1 (TRH-R1) is colocalized in NEI immunoreactive neurons in the peduncular part of the lateral hypothalamus (PLH) and NEI precursor mRNA expression increased by hypothyroidism indicating that NEI neurons are responsive to the feedback mechanisms of the Hypothalamic Pituitary-Thyroid Axis (HPT). In conclusion, the hypothyroid status seems to increase the interactions between the NEI neurons and the dopaminergic pathways while hyperthyroidism either decreases or displays no effects. Altogether these observations support the participation of the IHy and PLH NEI as a modulating component of the HPT suggesting that altered neuroendocrine, behavioral and cognitive dysfunctions induced by dysthyroidism could be in part mediated by NEI.
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Affiliation(s)
- Carolina Ayala
- Laboratorio de Neurobiología, Instituto de Embriología e Histología (IHEM-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo (UNCuyo), 5500, Mendoza, Argentina; Laboratorio de Ciencias Fisiológicas, Cátedra de Bacteriología y Virología Médicas, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, 5000, Córdoba, Argentina
| | - Gisela E Pennacchio
- Laboratorio de Reproducción y Lactancia, Instituto de Medicina y Biología Experimental de Cuyo (IMBECU-CONICET), Centro Científico Tecnológico (CCT), 5500, Mendoza, Argentina; Facultad de Ciencias Exactas y Naturales, UNCuyo, 5500, Mendoza, Argentina
| | - Marta Soaje
- Laboratorio de Reproducción y Lactancia, Instituto de Medicina y Biología Experimental de Cuyo (IMBECU-CONICET), Centro Científico Tecnológico (CCT), 5500, Mendoza, Argentina; Instituto de Fisiología, Facultad de Ciencias Médicas, UNCuyo, 5500, Mendoza, Argentina
| | - Jackson C Bittencourt
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Brazil
| | - María E Celis
- Laboratorio de Ciencias Fisiológicas, Cátedra de Bacteriología y Virología Médicas, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, 5000, Córdoba, Argentina
| | - Graciela A Jahn
- Laboratorio de Reproducción y Lactancia, Instituto de Medicina y Biología Experimental de Cuyo (IMBECU-CONICET), Centro Científico Tecnológico (CCT), 5500, Mendoza, Argentina
| | - Susana R Valdez
- Laboratorio de Reproducción y Lactancia, Instituto de Medicina y Biología Experimental de Cuyo (IMBECU-CONICET), Centro Científico Tecnológico (CCT), 5500, Mendoza, Argentina; Facultad de Ciencias Exactas y Naturales, UNCuyo, 5500, Mendoza, Argentina.
| | - Alicia M Seltzer
- Laboratorio de Neurobiología, Instituto de Embriología e Histología (IHEM-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo (UNCuyo), 5500, Mendoza, Argentina
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41
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Azeez IA, Del Gallo F, Cristino L, Bentivoglio M. Daily Fluctuation of Orexin Neuron Activity and Wiring: The Challenge of "Chronoconnectivity". Front Pharmacol 2018; 9:1061. [PMID: 30319410 PMCID: PMC6167434 DOI: 10.3389/fphar.2018.01061] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 09/03/2018] [Indexed: 12/12/2022] Open
Abstract
In the heterogeneous hub represented by the lateral hypothalamus, neurons containing the orexin/hypocretin peptides play a key role in vigilance state transitions and wakefulness stability, energy homeostasis, and other functions relevant for motivated behaviors. Orexin neurons, which project widely to the neuraxis, are innervated by multiple extra- and intra-hypothalamic sources. A key property of the adaptive capacity of orexin neurons is represented by daily variations of activity, which is highest in the period of the animal’s activity and wakefulness. These sets of data are here reviewed. They concern the discharge profile during the sleep/wake cycle, spontaneous Fos induction, peptide synthesis and release reflected by immunostaining intensity and peptide levels in the cerebrospinal fluid as well as postsynaptic effects. At the synaptic level, adaptive capacity of orexin neurons subserved by remodeling of excitatory and inhibitory inputs has been shown in response to changes in the nutritional status and prolonged wakefulness. The present review wishes to highlight that synaptic plasticity in the wiring of orexin neurons also occurs in unperturbed conditions and could account for diurnal variations of orexin neuron activity. Data in zebrafish larvae have shown rhythmic changes in the density of inhibitory innervation of orexin dendrites in relation to vigilance states. Recent findings in mice have indicated a diurnal reorganization of the excitatory/inhibitory balance in the perisomatic innervation of orexin neurons. Taken together these sets of data point to “chronoconnectivity,” i.e., a synaptic rearrangement of inputs to orexin neurons over the course of the day in relation to sleep and wake states. This opens questions on the underlying circadian and homeostatic regulation and on the involved players at synaptic level, which could implicate dual transmitters, cytoskeletal rearrangements, hormonal regulation, as well as surrounding glial cells and extracellular matrix. Furthermore, the question arises of a “chronoconnectivity” in the wiring of other neuronal cell groups of the sleep-wake-regulatory network, many of which are characterized by variations of their firing rate during vigilance states.
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Affiliation(s)
- Idris A Azeez
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Federico Del Gallo
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | | | - Marina Bentivoglio
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.,National Institute of Neuroscience, Verona Unit, Verona, Italy
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42
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Balkan B, Pogun S. Nicotinic Cholinergic System in the Hypothalamus Modulates the Activity of the Hypothalamic Neuropeptides During the Stress Response. Curr Neuropharmacol 2018; 16:371-387. [PMID: 28730966 PMCID: PMC6018196 DOI: 10.2174/1570159x15666170720092442] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 07/14/2017] [Accepted: 07/18/2017] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The hypothalamus harbors high levels of cholinergic neurons and axon terminals. Nicotinic acetylcholine receptors, which play an important role in cholinergic neurotransmission, are expressed abundantly in the hypothalamus. Accumulating evidence reveals a regulatory role for nicotine in the regulation of the stress responses. The present review will discuss the hypothalamic neuropeptides and their interaction with the nicotinic cholinergic system. The anatomical distribution of the cholinergic neurons, axon terminals and nicotinic receptors in discrete hypothalamic nuclei will be described. The effect of nicotinic cholinergic neurotransmission and nicotine exposure on hypothalamic-pituitaryadrenal (HPA) axis regulation at the hypothalamic level will be analyzed in view of the different neuropeptides involved. METHODS Published research related to nicotinic cholinergic regulation of the HPA axis activity at the hypothalamic level is reviewed. RESULTS The nicotinic cholinergic system is one of the major modulators of the HPA axis activity. There is substantial evidence supporting the regulation of hypothalamic neuropeptides by nicotinic acetylcholine receptors. However, most of the studies showing the nicotinic regulation of hypothalamic neuropeptides have employed systemic administration of nicotine. Additionally, we know little about the nicotinic receptor distribution on neuropeptide-synthesizing neurons in the hypothalamus and the physiological responses they trigger in these neurons. CONCLUSION Disturbed functioning of the HPA axis and hypothalamic neuropeptides results in pathologies such as depression, anxiety disorders and obesity, which are common and significant health problems. A better understanding of the nicotinic regulation of hypothalamic neuropeptides will aid in drug development and provide means to cope with these diseases. Considering that nicotine is also an abused substance, a better understanding of the role of the nicotinic cholinergic system on the HPA axis will aid in developing improved therapeutic strategies for smoking cessation.
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Affiliation(s)
- Burcu Balkan
- Center for Brain Research, Ege University, Bornova, Izmir, Turkey.,Department of Physiology, School of Medicine, Ege University, Bornova, Izmir, Turkey
| | - Sakire Pogun
- Center for Brain Research, Ege University, Bornova, Izmir, Turkey
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43
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Tesoriero C, Del Gallo F, Bentivoglio M. Sleep and brain infections. Brain Res Bull 2018; 145:59-74. [PMID: 30016726 DOI: 10.1016/j.brainresbull.2018.07.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 07/10/2018] [Accepted: 07/12/2018] [Indexed: 12/11/2022]
Abstract
Sleep is frequently altered in systemic infections as a component of sickness behavior in response to inflammation. Sleepiness in sickness behavior has been extensively investigated. Much less attention has instead been devoted to sleep and wake alterations in brain infections. Most of these, as other neuroinfections, are prevalent in sub-Saharan Africa. The present overview highlights the importance of this topic from both the clinical and pathogenetic points of view. Vigilance states and their regulation are first summarized, emphasizing that key nodes in this distributed brain system can be targeted by neuroinflammatory signaling. Sleep-wake changes in the parasitic disease human African trypanosomiasis (HAT) and its animal models are then reviewed and discussed. Experimental data have revealed that the suprachiasmatic nucleus, the master circadian pacemaker, and peptidergic cell populations of the lateral hypothalamus (the wake-promoting orexin neurons and the sleep-promoting melanin-concentrating hormone neurons) are targeted by African trypanosome infection. It is then discussed how prominent and disturbing are sleep changes in HIV/AIDS, also when the infection is cured with antiretroviral therapy. This recalls attention on the bidirectional interactions between sleep and immune system, including the specialized brain immune response of which microglial cells are protagonists. Sleep changes in an ancient viral disease, rabies, and in the emerging infection due to Zika virus which causes a congenital syndrome, are also dealt with. Altogether the findings indicate that sleep-wake regulation is targeted by brain infections caused by different pathogens and, although the relevant pathogenetic mechanisms largely remain to be clarified, these alterations differ from hypersomnia occurring in sickness behavior. Thus, brain infections point to the vulnerability of the neural network of sleep-wake regulation as a highly relevant clinical and basic science challenge.
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Affiliation(s)
- Chiara Tesoriero
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Italy
| | - Federico Del Gallo
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Italy
| | - Marina Bentivoglio
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Italy.
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Costa A, Castro-Zaballa S, Lagos P, Chase MH, Torterolo P. Distribution of MCH-containing fibers in the feline brainstem: Relevance for REM sleep regulation. Peptides 2018; 104:50-61. [PMID: 29680268 DOI: 10.1016/j.peptides.2018.04.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 03/15/2018] [Accepted: 04/09/2018] [Indexed: 11/20/2022]
Abstract
Neurons that utilize melanin-concentrating hormone (MCH) as a neuromodulator are localized in the postero-lateral hypothalamus and incerto-hypothalamic area. These neurons project diffusely throughout the central nervous system and have been implicated in critical physiological processes, such as sleep. Unlike rodents, in the order carnivora as well as in humans, MCH exerts its biological functions through two receptors: MCHR-1 and MCHR-2. Hence, the cat is an optimal animal to model MCHergic functions in humans. In the present study, we examined the distribution of MCH-positive fibers in the brainstem of the cat. MCHergic axons with distinctive varicosities and boutons were heterogeneously distributed, exhibiting different densities in distinct regions of the brainstem. High density of MCHergic fibers was found in the dorsal raphe nucleus, the laterodorsal tegmental nucleus, the periaqueductal gray, the pendunculopontine tegmental nucleus, the locus coeruleus and the prepositus hypoglossi. Because these areas are involved in the control of REM sleep, the present anatomical data support the role of this neuropeptidergic system in the control of this behavioral state.
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Affiliation(s)
- Alicia Costa
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Uruguay
| | | | - Patricia Lagos
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Uruguay
| | - Michael H Chase
- WebSciences International and UCLA School of Medicine, Los Angeles, USA
| | - Pablo Torterolo
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Uruguay.
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45
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Hwang YG, Lee HS. Neuropeptide Y (NPY) or cocaine- and amphetamine-regulated transcript (CART) fiber innervation on central and medial amygdaloid neurons that project to the locus coeruleus and dorsal raphe in the rat. Brain Res 2018; 1689:75-88. [DOI: 10.1016/j.brainres.2018.03.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 03/15/2018] [Accepted: 03/27/2018] [Indexed: 12/22/2022]
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46
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Laperchia C, Xu YZ, Mumba Ngoyi D, Cotrufo T, Bentivoglio M. Neural Damage in Experimental Trypanosoma brucei gambiense Infection: Hypothalamic Peptidergic Sleep and Wake-Regulatory Neurons. Front Neuroanat 2018. [PMID: 29535612 PMCID: PMC5835115 DOI: 10.3389/fnana.2018.00013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Neuron populations of the lateral hypothalamus which synthesize the orexin (OX)/hypocretin or melanin-concentrating hormone (MCH) peptides play crucial, reciprocal roles in regulating wake stability and sleep. The disease human African trypanosomiasis (HAT), also called sleeping sickness, caused by extracellular Trypanosoma brucei (T. b.) parasites, leads to characteristic sleep-wake cycle disruption and narcoleptic-like alterations of the sleep structure. Previous studies have revealed damage of OX and MCH neurons during systemic infection of laboratory rodents with the non-human pathogenic T. b. brucei subspecies. No information is available, however, on these peptidergic neurons after systemic infection with T. b. gambiense, the etiological agent of 97% of HAT cases. The present study was aimed at the investigation of immunohistochemically characterized OX and MCH neurons after T. b. gambiense or T. b. brucei infection of a susceptible rodent, the multimammate mouse, Mastomysnatalensis. Cell counts and evaluation of OX fiber density were performed at 4 and 8 weeks post-infection, when parasites had entered the brain parenchyma from the periphery. A significant decrease of OX neurons (about 44% reduction) and MCH neurons (about 54% reduction) was found in the lateral hypothalamus and perifornical area at 8 weeks in T. b. gambiense-infected M. natalensis. A moderate decrease (21% and 24% reduction, respectively), which did not reach statistical significance, was found after T. b. brucei infection. In two key targets of diencephalic orexinergic innervation, the peri-suprachiasmatic nucleus (SCN) region and the thalamic paraventricular nucleus (PVT), densitometric analyses showed a significant progressive decrease in the density of orexinergic fibers in both infection paradigms, and especially during T. b. gambiense infection. Altogether the findings provide novel information showing that OX and MCH neurons are highly vulnerable to chronic neuroinflammatory signaling caused by the infection of human-pathogenic African trypanosomes.
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Affiliation(s)
- Claudia Laperchia
- Department of Neuroscience Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Yuan-Zhong Xu
- Department of Neuroscience Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Dieudonné Mumba Ngoyi
- Institut National de Recherche Biomédicale (INRB), Kinshasa, Democratic Republic of Congo
| | - Tiziana Cotrufo
- Department of Neuroscience Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Marina Bentivoglio
- Department of Neuroscience Biomedicine and Movement Sciences, University of Verona, Verona, Italy.,National Institute of Neuroscience (INN), Verona Unit, Verona, Italy
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47
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Jancsik V, Bene R, Sótonyi P, Zachar G. Sub-cellular organization of the melanin-concentrating hormone neurons in the hypothalamus. Peptides 2018; 99:56-60. [PMID: 29108810 DOI: 10.1016/j.peptides.2017.11.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 10/30/2017] [Accepted: 11/02/2017] [Indexed: 12/22/2022]
Abstract
Melanin-concentrating hormone (MCH) is a potent orexigenic and sleep-promoting neuropeptide in mammals produced predominately by hypothalamic neurons which project to a wide variety of brain areas. Several MCH producing neurons contain MCH as the only neuropeptide, while others comprise cocaine- and amphetamine regulated transcript (CART) as well. The intrahypothalamic localization and the projection pattern of these two subpopulations are distinct. To provide structural grounding to understand the mechanism of action of MCH neurons we show here the subcellular localization of the neuropeptides in the two subpopulations within the hypothalamus of healthy young male mice by applying single and double immunofluorescence labelling.; Thick, prominent MCH immunopositive reticulation and fine discrete granules are detected within the perikarya of both CART positive and CART-free MCH neurons. Typically, one or more immunoreactive processes emanate from the perikarya. The bulk of CART immunoreactivity is also centrally positioned, surrounded by sparse immunoreactive granules within the perikarya and in the processes. In double immunopositive neurons, the two neuropeptides seem to colocalize in the heavily labelled central area, while the immunopositive granules in the cell body periphery and in the processes apparently contain either MCH or CART. This spatial arrangement suggests that MCH and CART, after being synthetized and processed in the endoplasmic reticulum/Golgi complex, are sorted into separate dense core vesicles, which then enter into the cell processes. This mechanism allows for both concerted and independent regulation of the transport and release of MCH and CART.
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Affiliation(s)
- Veronika Jancsik
- Department of Anatomy and Histology, University of Veterinary Medicine, Budapest, Hungary.
| | - Roland Bene
- Department of Anatomy and Histology, University of Veterinary Medicine, Budapest, Hungary
| | - Péter Sótonyi
- Department of Anatomy and Histology, University of Veterinary Medicine, Budapest, Hungary
| | - Gergely Zachar
- Department of Anatomy, Histology and Embryology, Semmelweis University Budapest, Hungary
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Hausen AC, Ruud J, Jiang H, Hess S, Varbanov H, Kloppenburg P, Brüning JC. Insulin-Dependent Activation of MCH Neurons Impairs Locomotor Activity and Insulin Sensitivity in Obesity. Cell Rep 2017; 17:2512-2521. [PMID: 27926856 DOI: 10.1016/j.celrep.2016.11.030] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 09/22/2016] [Accepted: 11/08/2016] [Indexed: 11/18/2022] Open
Abstract
Melanin-concentrating-hormone (MCH)-expressing neurons (MCH neurons) in the lateral hypothalamus (LH) are critical regulators of energy and glucose homeostasis. Here, we demonstrate that insulin increases the excitability of these neurons in control mice. In vivo, insulin promotes phosphatidylinositol 3-kinase (PI3K) signaling in MCH neurons, and cell-type-specific deletion of the insulin receptor (IR) abrogates this response. While lean mice lacking the IR in MCH neurons (IRΔMCH) exhibit no detectable metabolic phenotype under normal diet feeding, they present with improved locomotor activity and insulin sensitivity under high-fat-diet-fed, obese conditions. Similarly, obesity promotes PI3 kinase signaling in these neurons, and this response is abrogated in IRΔMCH mice. In turn, acute chemogenetic activation of MCH neurons impairs locomotor activity but not insulin sensitivity. Collectively, our experiments reveal an insulin-dependent activation of MCH neurons in obesity, which contributes via distinct mechanisms to the manifestation of impaired locomotor activity and insulin resistance.
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Affiliation(s)
- A Christine Hausen
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany
| | - Johan Ruud
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany
| | - Hong Jiang
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany
| | - Simon Hess
- Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany; Biocenter, Institute for Zoology, University of Cologne, Zülpicher Strasse 47b, 50674 Cologne, Germany
| | - Hristo Varbanov
- Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany; Biocenter, Institute for Zoology, University of Cologne, Zülpicher Strasse 47b, 50674 Cologne, Germany
| | - Peter Kloppenburg
- Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany; Biocenter, Institute for Zoology, University of Cologne, Zülpicher Strasse 47b, 50674 Cologne, Germany
| | - Jens C Brüning
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany; National Center for Diabetes Research (DZD), Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
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In vivo evaluation of radiotracers targeting the melanin-concentrating hormone receptor 1: [ 11C]SNAP-7941 and [ 18F]FE@SNAP reveal specific uptake in the ventricular system. Sci Rep 2017; 7:8054. [PMID: 28808288 PMCID: PMC5556108 DOI: 10.1038/s41598-017-08684-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 07/17/2017] [Indexed: 11/14/2022] Open
Abstract
The MCHR1 is involved in the regulation of energy homeostasis and changes of the expression are linked to a variety of associated diseases, such as diabetes and adiposity. The study aimed at the in vitro and in vivo evaluation of [11C]SNAP-7941 and [18F]FE@SNAP as potential PET-tracers for the MCHR1. Competitive binding studies with non-radioactive derivatives and small-animal PET/CT and MRI brain studies were performed under baseline conditions and tracer displacement with the unlabelled MCHR1 antagonist (±)-SNAP-7941. Binding studies evinced high binding affinity of the non-radioactive derivatives. Small-animal imaging of [11C]SNAP-7941 and [18F]FE@SNAP evinced high tracer uptake in MCHR1-rich regions of the ventricular system. Quantitative analysis depicted a significant tracer reduction after displacement with (±)-SNAP-7941. Due to the high binding affinity of the non-labelled derivatives and the high specific tracer uptake of [11C]SNAP-7941 and [18F]FE@SNAP, there is strong evidence that both radiotracers may serve as highly suitable agents for specific MCHR1 imaging.
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Diniz GB, Bittencourt JC. The Melanin-Concentrating Hormone as an Integrative Peptide Driving Motivated Behaviors. Front Syst Neurosci 2017; 11:32. [PMID: 28611599 PMCID: PMC5447028 DOI: 10.3389/fnsys.2017.00032] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 05/04/2017] [Indexed: 12/14/2022] Open
Abstract
The melanin-concentrating hormone (MCH) is an important peptide implicated in the control of motivated behaviors. History, however, made this peptide first known for its participation in the control of skin pigmentation, from which its name derives. In addition to this peripheral role, MCH is strongly implicated in motivated behaviors, such as feeding, drinking, mating and, more recently, maternal behavior. It is suggested that MCH acts as an integrative peptide, converging sensory information and contributing to a general arousal of the organism. In this review, we will discuss the various aspects of energy homeostasis to which MCH has been associated to, focusing on the different inputs that feed the MCH peptidergic system with information regarding the homeostatic status of the organism and the exogenous sensory information that drives this system, as well as the outputs that allow MCH to act over a wide range of homeostatic and behavioral controls, highlighting the available morphological and hodological aspects that underlie these integrative actions. Besides the well-described role of MCH in feeding behavior, a prime example of hypothalamic-mediated integration, we will also examine those functions in which the participation of MCH has not yet been extensively characterized, including sexual, maternal, and defensive behaviors. We also evaluated the available data on the distribution of MCH and its function in the context of animals in their natural environment. Finally, we briefly comment on the evidence for MCH acting as a coordinator between different modalities of motivated behaviors, highlighting the most pressing open questions that are open for investigations and that could provide us with important insights about hypothalamic-dependent homeostatic integration.
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Affiliation(s)
- Giovanne B. Diniz
- Laboratory of Chemical Neuroanatomy, Department of Anatomy, Institute of Biomedical Sciences, University of São PauloSão Paulo, Brazil
| | - Jackson C. Bittencourt
- Laboratory of Chemical Neuroanatomy, Department of Anatomy, Institute of Biomedical Sciences, University of São PauloSão Paulo, Brazil
- Center for Neuroscience and Behavior, Institute of Psychology, University of São PauloSão Paulo, Brazil
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