1
|
Rognoni CP, Serantes D, Rodriguez A, Mateos D, González J, Gallo D, Rivas M, Devera A, Lagos P, Rubido N, Torterolo P. Dorsal and median raphe neuronal firing dynamics characterized by nonlinear measures. PLoS Comput Biol 2024; 20:e1012111. [PMID: 38805554 DOI: 10.1371/journal.pcbi.1012111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 04/25/2024] [Indexed: 05/30/2024] Open
Abstract
The dorsal (DRN) and median (MRN) raphe are important nuclei involved in similar functions, including mood and sleep, but playing distinct roles. These nuclei have a different composition of neuronal types and set of neuronal connections, which among other factors, determine their neuronal dynamics. Most works characterize the neuronal dynamics using classic measures, such as using the average spiking frequency (FR), the coefficient of variation (CV), and action potential duration (APD). In the current study, to refine the characterization of neuronal firing profiles, we examined the neurons within the raphe nuclei. Through the utilization of nonlinear measures, our objective was to discern the redundancy and complementarity of these measures, particularly in comparison with classic methods. To do this, we analyzed the neuronal basal firing profile in both nuclei of urethane-anesthetized rats using the Shannon entropy (Bins Entropy) of the inter-spike intervals, permutation entropy of ordinal patterns (OP Entropy), and Permutation Lempel-Ziv Complexity (PLZC). Firstly, we found that classic (i.e., FR, CV, and APD) and nonlinear measures fail to distinguish between the dynamics of DRN and MRN neurons, except for the OP Entropy. We also found strong relationships between measures, including the CV with FR, CV with Bins entropy, and FR with PLZC, which imply redundant information. However, APD and OP Entropy have either a weak or no relationship with the rest of the measures tested, suggesting that they provide complementary information to the characterization of the neuronal firing profiles. Secondly, we studied how these measures are affected by the oscillatory properties of the firing patterns, including rhythmicity, bursting patterns, and clock-like behavior. We found that all measures are sensitive to rhythmicity, except for the OP Entropy. Overall, our work highlights OP Entropy as a powerful and useful quantity for the characterization of neuronal discharge patterns.
Collapse
Affiliation(s)
- Claudia Pascovich Rognoni
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
- Consciousness and Cognition Laboratory, Department of Psychology, King's College, University of Cambridge, Cambridge, United Kingdom
| | - Diego Serantes
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Alejo Rodriguez
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Diego Mateos
- Achucarro Basque Center for Neuroscience, Leioa (Bizkaia), Spain
- Instituto de Matemática Aplicada del Litoral (IMAL-CONICET-UNL), Santa Fé, Argentina
- Universidad Autónoma de Entre Ríos (UADER), Oro Verde, Entre Ríos, Argentina
| | - Joaquín González
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Diego Gallo
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Mayda Rivas
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Andrea Devera
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Patricia Lagos
- Laboratory of Neuropeptide Transmission, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Nicolás Rubido
- Institute for Complex Systems and Mathematical Biology, King's College, University of Aberdeen, Aberdeen, United Kingdom
| | - Pablo Torterolo
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| |
Collapse
|
2
|
Wang Y, Li D, Widjaja J, Guo R, Cai L, Yan R, Ozsoy S, Allocca G, Fang J, Dong Y, Tseng GC, Huang C, Huang YH. An EEG Signature of MCH Neuron Activities Predicts Cocaine Seeking. Biol Psychiatry 2024:S0006-3223(24)01257-5. [PMID: 38677639 DOI: 10.1016/j.biopsych.2024.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 04/02/2024] [Accepted: 04/15/2024] [Indexed: 04/29/2024]
Abstract
BACKGROUND Identifying biomarkers that predict substance use disorder (SUD) propensity may better strategize anti-addiction treatment. The melanin-concentrating hormone (MCH) neurons in the lateral hypothalamus (LH) critically mediates interactions between sleep and substance use; however, their activities are largely obscured in surface electroencephalogram (EEG) measures, hindering the development of biomarkers. METHODS Surface EEG signals and real-time Ca2+ activities of LH MCH neurons (Ca2+MCH) were simultaneously recorded in male and female adult rats. Mathematical modeling and machine learning were then applied to predict Ca2+MCH using EEG derivatives. The robustness of the predictions was tested across sex and treatment conditions. Finally, features extracted from the EEG-predicted Ca2+MCH either before or after cocaine experience were used to predict future drug-seeking behaviors. RESULTS An EEG waveform derivative - a modified theta-to-delta ratio (EEG Ratio) - accurately tracks real-time Ca2+MCH in rats. The prediction was robust during rapid eye movement sleep (REMS), persisted through REMS manipulations, wakefulness, circadian phases, and was consistent across sex. Moreover, cocaine self-administration and long-term withdrawal altered EEG Ratio suggesting shortening and circadian redistribution of synchronous MCH neuron activities. In addition, features of EEG Ratio indicative of prolonged synchronous MCH neuron activities predicted lower subsequent cocaine seeking. EEG Ratio also exhibited advantages over conventional REMS measures for the predictions. CONCLUSIONS The identified EEG Ratio may serve as a non-invasive measure for assessing MCH neuron activities in vivo and evaluating REMS; it may also serve as a potential biomarker predicting drug use propensity.
Collapse
Affiliation(s)
- Yao Wang
- Departments of Psychiatry, Pittsburgh, PA, 15219; Neuroscience, andUniversity of Pittsburgh, Pittsburgh, PA, 15260
| | - Danyang Li
- Biostatistics, University of Pittsburgh, Pittsburgh, PA, 15213
| | | | - Rong Guo
- Departments of Psychiatry, Pittsburgh, PA, 15219
| | - Li Cai
- Departments of Psychiatry, Pittsburgh, PA, 15219
| | - Rongzhen Yan
- Departments of Psychiatry, Pittsburgh, PA, 15219
| | - Sahin Ozsoy
- Somnivore Pty. Ltd., Bacchus Marsh, VIC, Australia 3340
| | - Giancarlo Allocca
- Somnivore Pty. Ltd., Bacchus Marsh, VIC, Australia 3340; Department of Pharmacology and Therapeutics, The University of Melbourne, VIC, Australia 3010; The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC, Australia
| | - Jidong Fang
- Department of Psychiatry and Behavioral Health, Penn State College of Medicine, Hershey, PA 17033
| | - Yan Dong
- Neuroscience, andUniversity of Pittsburgh, Pittsburgh, PA, 15260
| | - George C Tseng
- Biostatistics, University of Pittsburgh, Pittsburgh, PA, 15213
| | - Chengcheng Huang
- Neuroscience, andUniversity of Pittsburgh, Pittsburgh, PA, 15260
| | | |
Collapse
|
3
|
Wang Y, Li D, Widjaja J, Guo R, Cai L, Yan R, Ozsoy S, Allocca G, Fang J, Dong Y, Tseng GC, Huang C, Huang YH. An EEG Signature of MCH Neuron Activities Predicts Cocaine Seeking. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.27.586887. [PMID: 38586019 PMCID: PMC10996698 DOI: 10.1101/2024.03.27.586887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Background Identifying biomarkers that predict substance use disorder (SUD) propensity may better strategize anti-addiction treatment. The melanin-concentrating hormone (MCH) neurons in the lateral hypothalamus (LH) critically mediates interactions between sleep and substance use; however, their activities are largely obscured in surface electroencephalogram (EEG) measures, hindering the development of biomarkers. Methods Surface EEG signals and real-time Ca2+ activities of LH MCH neurons (Ca2+MCH) were simultaneously recorded in male and female adult rats. Mathematical modeling and machine learning were then applied to predict Ca2+MCH using EEG derivatives. The robustness of the predictions was tested across sex and treatment conditions. Finally, features extracted from the EEG-predicted Ca2+MCH either before or after cocaine experience were used to predict future drug-seeking behaviors. Results An EEG waveform derivative - a modified theta-to-delta ratio (EEG Ratio) - accurately tracks real-time Ca2+MCH in rats. The prediction was robust during rapid eye movement sleep (REMS), persisted through REMS manipulations, wakefulness, circadian phases, and was consistent across sex. Moreover, cocaine self-administration and long-term withdrawal altered EEG Ratio suggesting shortening and circadian redistribution of synchronous MCH neuron activities. In addition, features of EEG Ratio indicative of prolonged synchronous MCH neuron activities predicted lower subsequent cocaine seeking. EEG Ratio also exhibited advantages over conventional REMS measures for the predictions. Conclusions The identified EEG Ratio may serve as a non-invasive measure for assessing MCH neuron activities in vivo and evaluating REMS; it may also serve as a potential biomarker predicting drug use propensity.
Collapse
Affiliation(s)
- Yao Wang
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15219; 15260; 15213
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA 15219; 15260; 15213
| | - Danyang Li
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, PA 15219; 15260; 15213
| | | | - Rong Guo
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15219; 15260; 15213
| | - Li Cai
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15219; 15260; 15213
| | - Rongzhen Yan
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15219; 15260; 15213
| | - Sahin Ozsoy
- Somnivore Pty. Ltd., Bacchus Marsh, VIC, Australia 3340
| | - Giancarlo Allocca
- Somnivore Pty. Ltd., Bacchus Marsh, VIC, Australia 3340
- Department of Pharmacology and Therapeutics, The University of Melbourne, VIC, Australia 3010
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC, Australia
| | - Jidong Fang
- Department of Psychiatry and Behavioral Health, Penn State College of Medicine, Hershey, PA 17033
| | - Yan Dong
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA 15219; 15260; 15213
| | - George C. Tseng
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, PA 15219; 15260; 15213
| | - Chengcheng Huang
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA 15219; 15260; 15213
| | - Yanhua H. Huang
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15219; 15260; 15213
| |
Collapse
|
4
|
Guo R, Wang Y, Yan R, Chen B, Ding W, Gorczyca MT, Ozsoy S, Cai L, Hines RL, Tseng GC, Allocca G, Dong Y, Fang J, Huang YH. Rapid Eye Movement Sleep Engages Melanin-Concentrating Hormone Neurons to Reduce Cocaine Seeking. Biol Psychiatry 2022; 92:880-894. [PMID: 35953320 PMCID: PMC9872495 DOI: 10.1016/j.biopsych.2022.06.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 06/03/2022] [Accepted: 06/06/2022] [Indexed: 01/27/2023]
Abstract
BACKGROUND Persistent sleep disruptions following withdrawal from abused drugs may hold keys to battle drug relapse. It is posited that there may be sleep signatures that predict relapse propensity, identifying which may open new avenues for treating substance use disorders. METHODS We trained male rats (approximately postnatal day 56) to self-administer cocaine. After long-term drug withdrawal (approximately postnatal day 100), we examined the correlations between the intensity of cocaine seeking and key sleep features. To test for causal relationships, we then used behavioral, chemogenetic, or optogenetic methods to selectively increase rapid eye movement sleep (REMS) and measured behavioral and electrophysiological outcomes to probe for cellular and circuit mechanisms underlying REMS-mediated regulation of cocaine seeking. RESULTS A selective set of REMS features was preferentially associated with the intensity of cue-induced cocaine seeking after drug withdrawal. Moreover, selectively increasing REMS time and continuity by environmental warming attenuated a withdrawal time-dependent intensification of cocaine seeking, or incubation of cocaine craving, suggesting that REMS may benefit withdrawal. Warming increased the activity of lateral hypothalamic melanin-concentrating hormone (MCH) neurons selectively during prolonged REMS episodes and counteracted cocaine-induced synaptic accumulation of calcium-permeable AMPA receptors in the nucleus accumbens-a critical substrate for incubation. Finally, the warming effects were partly mimicked by chemogenetic or optogenetic stimulations of MCH neurons during sleep, or intra-accumbens infusions of MCH peptide during the rat's inactive phase. CONCLUSIONS REMS may encode individual vulnerability to relapse, and MCH neuron activities can be selectively targeted during REMS to reduce drug relapse.
Collapse
Affiliation(s)
- Rong Guo
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Yao Wang
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Rongzhen Yan
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Bo Chen
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Wanqiao Ding
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Michael T Gorczyca
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Sahin Ozsoy
- Somnivore Pty. Ltd., Bacchus Marsh, Victoria, Australia
| | - Li Cai
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Rachel L Hines
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - George C Tseng
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Giancarlo Allocca
- Somnivore Pty. Ltd., Bacchus Marsh, Victoria, Australia; Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, Victoria, Australia; Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Yan Dong
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Jidong Fang
- Department of Psychiatry and Behavioral Health, Penn State College of Medicine, Hershey, Pennsylvania
| | - Yanhua H Huang
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania.
| |
Collapse
|
5
|
Potter LE, Burgess CR. The melanin-concentrating hormone system as a target for the treatment of sleep disorders. Front Neurosci 2022; 16:952275. [PMID: 36177357 PMCID: PMC9513178 DOI: 10.3389/fnins.2022.952275] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 08/24/2022] [Indexed: 11/13/2022] Open
Abstract
Given the widespread prevalence of sleep disorders and their impacts on health, it is critical that researchers continue to identify and evaluate novel avenues of treatment. Recently the melanin-concentrating hormone (MCH) system has attracted commercial and scientific interest as a potential target of pharmacotherapy for sleep disorders. This interest emerges from basic scientific research demonstrating a role for MCH in regulating sleep, and particularly REM sleep. In addition to this role in sleep regulation, the MCH system and the MCH receptor 1 (MCHR1) have been implicated in a wide variety of other physiological functions and behaviors, including feeding/metabolism, reward, anxiety, depression, and learning. The basic research literature on sleep and the MCH system, and the history of MCH drug development, provide cause for both skepticism and cautious optimism about the prospects of MCH-targeting drugs in sleep disorders. Extensive efforts have focused on developing MCHR1 antagonists for use in obesity, however, few of these drugs have advanced to clinical trials, and none have gained regulatory approval. Additional basic research will be needed to fully characterize the MCH system’s role in sleep regulation, for example, to fully differentiate between MCH-neuron and peptide/receptor-mediated functions. Additionally, a number of issues relating to drug design will continue to pose a practical challenge for novel pharmacotherapies targeting the MCH system.
Collapse
Affiliation(s)
- Liam E. Potter
- Department of Molecular and Integrative Physiology, Michigan Medicine, Ann Arbor, MI, United States
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, United States
- *Correspondence: Liam E. Potter,
| | - Christian R. Burgess
- Department of Molecular and Integrative Physiology, Michigan Medicine, Ann Arbor, MI, United States
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, United States
- Christian R. Burgess,
| |
Collapse
|
6
|
Rivas M, Serantes D, Peña F, González J, Ferreira A, Torterolo P, Benedetto L. Role of Hypocretin in the Medial Preoptic Area in the Regulation of Sleep, Maternal Behavior and Body Temperature of Lactating Rats. Neuroscience 2021; 475:148-162. [PMID: 34500018 DOI: 10.1016/j.neuroscience.2021.08.034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 08/23/2021] [Accepted: 08/29/2021] [Indexed: 12/11/2022]
Abstract
Hypocretins (HCRT), also known as orexins, includes two neuroexcitatory peptides, HCRT-1 and HCRT-2 (orexin A y B, respectively), synthesized by neurons located in the postero-lateral hypothalamus, whose projections and receptors are widely distributed throughout the brain, including the medial preoptic area (mPOA). HCRT have been associated with a wide range of physiological functions including sleep-wake cycle, maternal behavior and body temperature, all regulated by the mPOA. Previously, we showed that HCRT in the mPOA facilitates certain active maternal behaviors, while the blockade of HCRT-R1 increases the time spent in nursing. As mother rats mainly sleep while they nurse, we hypothesize that HCRT in the mPOA of lactating rats reduce sleep and nursing, while intra-mPOA administration of a dual orexin receptor antagonist (DORA) would cause the opposite effect. Therefore, the aim of this study was to determine the role of HCRT within the mPOA, in the regulation and integration of the sleep-wake cycle, maternal behavior and body temperature of lactating rats. For that purpose, we assessed the sleep-wake states, maternal behavior and body temperature of lactating rats following microinjections of HCRT-1 (100 and 200 µM) and DORA (5 mM) into the mPOA. As expected, our data show that HCRT-1 in mPOA promote wakefulness and a slightly increase in body temperature, whereas DORA increases both NREM and REM sleep together with an increment of nursing and milk ejection. Taken together, our results strongly suggest that the endogenous reduction of HCRT within the mPOA contribute to the promotion of sleep, milk ejection and nursing behavior in lactating rats.
Collapse
Affiliation(s)
- Mayda Rivas
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Diego Serantes
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Florencia Peña
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Joaquín González
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Annabel Ferreira
- Sección de Fisiología y Nutrición, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Pablo Torterolo
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Luciana Benedetto
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
| |
Collapse
|
7
|
Seifinejad A, Vassalli A, Tafti M. Neurobiology of cataplexy. Sleep Med Rev 2021; 60:101546. [PMID: 34607185 DOI: 10.1016/j.smrv.2021.101546] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 07/29/2021] [Accepted: 09/06/2021] [Indexed: 11/17/2022]
Abstract
Cataplexy is the pathognomonic and the most striking symptom of narcolepsy. It has originally been, and still is now, widely considered as an abnormal manifestation of rapid eye movement (REM) sleep during wakefulness due to the typical muscle atonia. The neurocircuits of cataplexy, originally confined to the brainstem as those of REM sleep atonia, now include the hypothalamus, dorsal raphe (DR), amygdala and frontal cortex, and its neurochemistry originally focused on catecholamines and acetylcholine now extend to hypocretin (HCRT) and other neuromodulators. Here, we review the neuroanatomy and neurochemistry of cataplexy and propose that cataplexy is a distinct brain state that, despite similarities with REM sleep, involves cataplexy-specific features.
Collapse
Affiliation(s)
- Ali Seifinejad
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, 1005 Lausanne, Switzerland
| | - Anne Vassalli
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, 1005 Lausanne, Switzerland
| | - Mehdi Tafti
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, 1005 Lausanne, Switzerland.
| |
Collapse
|
8
|
Cocaine-induced neural adaptations in the lateral hypothalamic melanin-concentrating hormone neurons and the role in regulating rapid eye movement sleep after withdrawal. Mol Psychiatry 2021; 26:3152-3168. [PMID: 33093653 PMCID: PMC8060355 DOI: 10.1038/s41380-020-00921-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 09/30/2020] [Accepted: 10/07/2020] [Indexed: 12/21/2022]
Abstract
Sleep abnormalities are often a prominent contributor to withdrawal symptoms following chronic drug use. Notably, rapid eye movement (REM) sleep regulates emotional memory, and persistent REM sleep impairment after cocaine withdrawal negatively impacts relapse-like behaviors in rats. However, it is not understood how cocaine experience may alter REM sleep regulatory machinery, and what may serve to improve REM sleep after withdrawal. Here, we focus on the melanin-concentrating hormone (MCH) neurons in the lateral hypothalamus (LH), which regulate REM sleep initiation and maintenance. Using adult male Sprague-Dawley rats trained to self-administer intravenous cocaine, we did transcriptome profiling of LH MCH neurons after long-term withdrawal using RNA-sequencing, and performed functional assessment using slice electrophysiology. We found that 3 weeks after withdrawal from cocaine, LH MCH neurons exhibit a wide range of gene expression changes tapping into cell membrane signaling, intracellular signaling, and transcriptional regulations. Functionally, they show reduced membrane excitability and decreased glutamatergic receptor activity, consistent with increased expression of voltage-gated potassium channel gene Kcna1 and decreased expression of metabotropic glutamate receptor gene Grm5. Finally, chemogenetic or optogenetic stimulations of LH MCH neural activity increase REM sleep after long-term withdrawal with important differences. Whereas chemogenetic stimulation promotes both wakefulness and REM sleep, optogenetic stimulation of these neurons in sleep selectively promotes REM sleep. In summary, cocaine exposure persistently alters gene expression profiles and electrophysiological properties of LH MCH neurons. Counteracting cocaine-induced hypoactivity of these neurons selectively in sleep enhances REM sleep quality and quantity after long-term withdrawal.
Collapse
|
9
|
Diniz GB, Battagello DS, Cherubini PM, Reyes-Mendoza JD, Luna-Illades C, Klein MO, Motta-Teixeira LC, Sita LV, Miranda-Anaya M, Morales T, Bittencourt JC. Melanin-concentrating hormone peptidergic system: Comparative morphology between muroid species. J Comp Neurol 2019; 527:2973-3001. [PMID: 31152440 DOI: 10.1002/cne.24723] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 05/23/2019] [Accepted: 05/24/2019] [Indexed: 12/15/2022]
Abstract
Melanin-concentrating hormone (MCH) is a conserved neuropeptide, predominantly located in the diencephalon of vertebrates, and associated with a wide range of functions. While functional studies have focused on the use of the traditional mouse laboratory model, critical gaps exist in our understanding of the morphology of the MCH system in this species. Even less is known about the nontraditional animal model Neotomodon alstoni (Mexican volcano mouse). A comparative morphological study among these rodents may, therefore, contribute to a better understanding of the evolution of the MCH peptidergic system. To this end, we employed diverse immunohistochemical protocols to identify key aspects of the MCH system, including its spatial relationship to another neurochemical population of the tuberal hypothalamus, the orexins. Three-dimensional (3D) reconstructions were also employed to convey a better sense of spatial distribution to these neurons. Our results show that the distribution of MCH neurons in all rodents studied follows a basic plan, but individual characteristics are found for each species, such as the preeminence of a periventricular group only in the rat, the lack of posterior groups in the mouse, and the extensive presence of MCH neurons in the anterior hypothalamic area of Neotomodon. Taken together, these data suggest a strong anatomical substrate for previously described functions of the MCH system, and that particular neurochemical and morphological features may have been determinant to species-specific phenotypes in rodent evolution.
Collapse
Affiliation(s)
- Giovanne B Diniz
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Daniella S Battagello
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.,Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Santiago de Querétaro, Queretaro, Mexico
| | - Pedro M Cherubini
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Julio D Reyes-Mendoza
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Santiago de Querétaro, Queretaro, Mexico
| | - Cesar Luna-Illades
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Santiago de Querétaro, Queretaro, Mexico
| | - Marianne O Klein
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Lívia C Motta-Teixeira
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.,Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Luciane V Sita
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Manuel Miranda-Anaya
- Unidad Multidisciplinaria de Docencia e Investigación, Facultad de Ciencias, Universidad Nacional Autónoma de México, Santiago de Querétaro, Queretaro, Mexico
| | - Teresa Morales
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Santiago de Querétaro, Queretaro, Mexico
| | - Jackson C Bittencourt
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.,Center for Neuroscience and Behavior, Institute of Psychology, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
10
|
Yakupov EZ, Artemieva DV, Troshina YV. [Multimodality of clinical effects of orexin]. Zh Nevrol Psikhiatr Im S S Korsakova 2019; 118:114-119. [PMID: 30698570 DOI: 10.17116/jnevro2018118121114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The article describes the main biological properties of orexin as a wakefulness hormone and its possible points of application in practical medicine. An example of a drug, which blocks orexin receptors and can be used as a hypnotic drug to treat sleep disorders, is presented.
Collapse
Affiliation(s)
- E Z Yakupov
- Kazan State Medical University, Kazan, Russia
| | | | | |
Collapse
|
11
|
Saiz-Bianco E, Urbanavicius J, Prunell G, Lagos P. Melanin-concentrating hormone does not modulate serotonin release in primary cultures of fetal raphe nucleus neurons. Neuropeptides 2019; 74:70-81. [PMID: 30642579 DOI: 10.1016/j.npep.2018.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 12/03/2018] [Accepted: 12/30/2018] [Indexed: 11/18/2022]
Abstract
Melanin-concentrating hormone (MCH) is a neuropeptide present in neurons located in the hypothalamus that densely innervate serotonergic cells in the dorsal raphe nucleus (DRN). MCH administration into the DRN induces a depressive-like effect through a serotonergic mechanism. To further understand the interaction between MCH and serotonin, we used primary cultured serotonergic neurons to evaluate the effect of MCH on serotonergic release and metabolism by HPLC-ED measurement of serotonin (5-HT) and 5-hydroxyindolacetic acid (5-HIAA) levels. We confirmed the presence of serotonergic neurons in the E14 rat rhombencephalon by immunohistochemistry and showed for the first time evidence of MCHergic fibers reaching the area. Cultures obtained from rhombencephalic tissue presented 2.2 ± 0.7% of serotonergic and 48.9 ± 5.4% of GABAergic neurons. Despite the low concentration of serotonergic neurons, we were able to measure basal cellular and extracellular levels of 5-HT and 5-HIAA without the addition of any serotonergic-enhancer drug. As expected, 5-HT release was calcium-dependent and induced by depolarization. 5-HT extracellular levels were significantly increased by incubation with serotonin reuptake inhibitors (citalopram and nortriptyline) and a monoamine-oxidase inhibitor (clorgyline), and were not significantly modified by a 5-HT1A autoreceptor agonist (8-OHDPAT). Even though serotonergic cells responded as expected to these pharmacological treatments, MCH did not induce significant modifications of 5-HT and 5-HIAA extracellular levels in the cultures. Despite this unexpected result, we consider that assessment of 5-HT and 5-HIAA levels in primary serotonergic cultures may be an adequate approach to study the effect of other drugs and modulators on serotonin release, uptake and turnover.
Collapse
Affiliation(s)
- Eugenia Saiz-Bianco
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Jessika Urbanavicius
- Departamento de Neurofarmacología Experimental, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Giselle Prunell
- Departamento de Neuroquímica, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay.
| | - Patricia Lagos
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
| |
Collapse
|
12
|
Pérez-Morales M, Hurtado-Alvarado G, Morales-Hernández I, Gómez-González B, Domínguez-Salazar E, Velázquez-Moctezuma J. Postnatal overnutrition alters the orexigenic effects of melanin-concentrating hormone (MCH) and reduces MCHR1 hypothalamic expression on spontaneous feeding and fasting. Pharmacol Biochem Behav 2018; 175:53-61. [PMID: 30196088 DOI: 10.1016/j.pbb.2018.09.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 09/04/2018] [Accepted: 09/05/2018] [Indexed: 01/04/2023]
Abstract
One of the approaches to induce obesity in rodents consists in reducing litter size to 3 pups during the lactation period. Animals submitted to this manipulation are heavier, hyperphagic and develop several metabolic diseases for the rest of their lives. In the present study, under the premise that melanin-concentrating hormone (MCH), an orexigenic peptide synthesized by neurons of the lateral hypothalamus, is involved in food intake regulation, we aimed to measure the hypothalamic expression of its receptor, MCHR1, in adult early overfed obese animals and normoweight controls at both ad libitum and food deprived conditions. Additionally, we administered MCH, or an antiMCH antibody, into the third ventricle of ad libitum-fed rats, or fasted rats, respectively, and evaluated chow consumption. Typical nocturnal hyperphagia in rodents was elevated in obese animals compared to normoweight controls, accompanied by a lower expression of MCHR1 and leptin receptor (Ob-R). Following a 24 h fasting, MCHR1 remained lower in SL rats. After 4 h of re-feeding, obese animals ate more than normoweight controls. MCH failed to enhance appetite in early overfed obese animals and immunoneutralization of the peptide only reduced fasted induced-hyperphagia in normoweight controls. These results support the notion that both peptide and brain endogenous MCH exert a physiological relevant action in food intake regulation in normoweight rats, but that postnatal overnutrition disturbs this system, as reflected by MCHR1 downregulation at both ad libitum and fasted conditions and in the lack of response to MCH in both positive- and negative-energetic states in early overfed obese animals.
Collapse
Affiliation(s)
- Marcel Pérez-Morales
- Area of Neurosciences, Department of Biology of Reproduction, CBS, Universidad Autónoma Metropolitana, Unidad Iztapalapa, México City, México.
| | - Gabriela Hurtado-Alvarado
- Area of Neurosciences, Department of Biology of Reproduction, CBS, Universidad Autónoma Metropolitana, Unidad Iztapalapa, México City, México
| | - Itzel Morales-Hernández
- Area of Neurosciences, Department of Biology of Reproduction, CBS, Universidad Autónoma Metropolitana, Unidad Iztapalapa, México City, México
| | - Beatriz Gómez-González
- Area of Neurosciences, Department of Biology of Reproduction, CBS, Universidad Autónoma Metropolitana, Unidad Iztapalapa, México City, México.
| | - Emilio Domínguez-Salazar
- Area of Neurosciences, Department of Biology of Reproduction, CBS, Universidad Autónoma Metropolitana, Unidad Iztapalapa, México City, México
| | - Javier Velázquez-Moctezuma
- Area of Neurosciences, Department of Biology of Reproduction, CBS, Universidad Autónoma Metropolitana, Unidad Iztapalapa, México City, México.
| |
Collapse
|
13
|
Shiromani PJ, Peever JH. New Neuroscience Tools That Are Identifying the Sleep-Wake Circuit. Sleep 2017; 40:3059391. [PMID: 28329204 DOI: 10.1093/sleep/zsx032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The complexity of the brain is yielding to technology. In the area of sleep neurobiology, conventional neuroscience tools such as lesions, cell recordings, c-Fos, and axon-tracing methodologies have been instrumental in identifying the complex and intermingled populations of sleep- and arousal-promoting neurons that orchestrate and generate wakefulness, NREM, and REM sleep. In the last decade, new technologies such as optogenetics, chemogenetics, and the CRISPR-Cas system have begun to transform how biologists understand the finer details associated with sleep-wake regulation. These additions to the neuroscience toolkit are helping to identify how discrete populations of brain cells function to trigger and shape the timing and transition into and out of different sleep-wake states, and how glia partner with neurons to regulate sleep. Here, we detail how some of the newest technologies are being applied to understand the neural circuits underlying sleep and wake.
Collapse
Affiliation(s)
- Priyattam J Shiromani
- Ralph H. Johnson Veterans Administration Medical Center, Research Service, Charleston, SC
| | - John H Peever
- Centre for Biological Timing and Cognition, Department Cell and Systems Biology, and Physiology, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
14
|
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: 61] [Impact Index Per Article: 8.7] [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.
Collapse
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
| |
Collapse
|
15
|
Qiu MH, Chen MC, Fuller PM, Lu J. Stimulation of the Pontine Parabrachial Nucleus Promotes Wakefulness via Extra-thalamic Forebrain Circuit Nodes. Curr Biol 2016; 26:2301-12. [PMID: 27546576 DOI: 10.1016/j.cub.2016.07.054] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 07/09/2016] [Accepted: 07/20/2016] [Indexed: 01/08/2023]
Abstract
Human and animal studies have identified an especially critical role for the brainstem parabrachial (PB) complex in regulating electrocortical (electroencephalogram [EEG]) and behavioral arousal: lesions of the PB complex produce a monotonous high-voltage, slow-wave EEG and eliminate spontaneous behaviors. We report here that targeted chemogenetic activation of the PB complex produces sustained EEG and behavioral arousal in the rat. We further establish, using viral-mediated retrograde activation, that PB projections to the preoptic-basal forebrain and lateral hypothalamus, but not to the thalamus, mediate PB-driven wakefulness. We exploited this novel and noninvasive model of induced wakefulness to explore the EEG and metabolic consequences of extended wakefulness. Repeated (daily) chemogenetic activation of the PB was highly effective in extending wakefulness over 4 days, although subsequent PB activation produced progressively lesser wake amounts. Curiously, no EEG or behavioral sleep rebound was observed, even after 4 days of induced wakefulness. Following the last of the four daily induced wake bouts, we examined the brains and observed a chimeric pattern of c-Fos expression, with c-Fos expressed in subsets of both arousal- and sleep-promoting nuclei. From a metabolic standpoint, induced extended wakefulness significantly reduced body weight and leptin but was without significant effect on cholesterol, triglyceride, or insulin levels, suggesting that high sleep pressure or sleep debt per se does not, as previously implicated, result in a deleterious metabolic phenotype.
Collapse
Affiliation(s)
- Mei Hong Qiu
- Department of Neurobiology, School of Basic Medical Science, Fudan University, Shanghai 200032, China; Department of Pharmacology, School of Basic Medical Science, Fudan University, Shanghai 200032, China; Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02115, USA.
| | - Michael C Chen
- Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02115, USA
| | - Patrick M Fuller
- Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02115, USA
| | - Jun Lu
- Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
16
|
Calegare BF, Costa A, Fernandes L, Dias AL, Torterolo P, Almeida VD. Subchronical treatment with Fluoxetine modifies the activity of the MCHergic and hypocretinergic systems. Evidences from peptide CSF concentration and gene expression. Sleep Sci 2016; 9:89-93. [PMID: 27656272 PMCID: PMC5022008 DOI: 10.1016/j.slsci.2016.05.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 04/25/2016] [Accepted: 05/31/2016] [Indexed: 01/02/2023] Open
Abstract
In the postero-lateral hypothalamus are located two neuronal systems that utilize the neuropeptides melanin-concentrating hormone (MCH) and hypocretins (also called orexins) as neuromodulators. These systems have reciprocal connections between them, and project throughout the central nervous system. MCH has been involved in the generation of sleep, mainly REM sleep, while hypocretins have a critical role in the generation of wakefulness. MCHergic activity is also involved in the pathophysiology of major depressive disorder (MD). In this regards, intracerebral administration of MCH promotes pro-depressive behaviors (i.e., immobility in the forced swimming test) and REM sleep hypersomnia, which is an important trait of depression. Furthermore, the antagonism of the MCHR-1 receptor has a reliable antidepressant effect, suggesting that MCH is a pro-depressive factor. Hypocretins have been also involved in mood regulation; however, their role in depression is still on debate. Taking these data into account, we explored whether systemic subchronical treatment with Fluoxetine (FLX), a serotonergic antidepressant, modifies the concentration of MCH in the cerebrospinal fluid (CSF), as well as the preproMCH mRNA expression. We also evaluated the hypocretinergic system by quantifying the hypocretin-levels in the CSF and the preprohypocretin mRNA expression. Compared to control, FLX increased the levels of preprohypocretin mRNA without affecting the hypocretin-1 CSF levels. On the contrary, FLX significantly decreased the MCH CSF concentration without affecting the preproMCH gene expression. This result is in agreement with the fact that MCH serum level diminishes during the antidepressant treatment in MD, and supports the hypothesis that an increase in the MCHergic activity could have pro-depressive consequences.
Collapse
Affiliation(s)
- Bruno F. Calegare
- Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Alicia Costa
- Department of Physiology, School of Medicine, Universidad de la República, Montevideo, Uruguay
| | - Leandro Fernandes
- Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Ana L. Dias
- Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Pablo Torterolo
- Department of Physiology, School of Medicine, Universidad de la República, Montevideo, Uruguay
| | - Vânia D’ Almeida
- Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil
| |
Collapse
|
17
|
Torterolo P, Scorza C, Lagos P, Urbanavicius J, Benedetto L, Pascovich C, López-Hill X, Chase MH, Monti JM. Melanin-Concentrating Hormone (MCH): Role in REM Sleep and Depression. Front Neurosci 2015; 9:475. [PMID: 26733789 PMCID: PMC4681773 DOI: 10.3389/fnins.2015.00475] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Accepted: 11/26/2015] [Indexed: 12/05/2022] Open
Abstract
The melanin-concentrating hormone (MCH) is a peptidergic neuromodulator synthesized by neurons of the lateral sector of the posterior hypothalamus and zona incerta. MCHergic neurons project throughout the central nervous system, including areas such as the dorsal (DR) and median (MR) raphe nuclei, which are involved in the control of sleep and mood. Major Depression (MD) is a prevalent psychiatric disease diagnosed on the basis of symptomatic criteria such as sadness or melancholia, guilt, irritability, and anhedonia. A short REM sleep latency (i.e., the interval between sleep onset and the first REM sleep period), as well as an increase in the duration of REM sleep and the density of rapid-eye movements during this state, are considered important biological markers of depression. The fact that the greatest firing rate of MCHergic neurons occurs during REM sleep and that optogenetic stimulation of these neurons induces sleep, tends to indicate that MCH plays a critical role in the generation and maintenance of sleep, especially REM sleep. In addition, the acute microinjection of MCH into the DR promotes REM sleep, while immunoneutralization of this peptide within the DR decreases the time spent in this state. Moreover, microinjections of MCH into either the DR or MR promote a depressive-like behavior. In the DR, this effect is prevented by the systemic administration of antidepressant drugs (either fluoxetine or nortriptyline) and blocked by the intra-DR microinjection of a specific MCH receptor antagonist. Using electrophysiological and microdialysis techniques we demonstrated also that MCH decreases the activity of serotonergic DR neurons. Therefore, there are substantive experimental data suggesting that the MCHergic system plays a role in the control of REM sleep and, in addition, in the pathophysiology of depression. Consequently, in the present report, we summarize and evaluate the current data and hypotheses related to the role of MCH in REM sleep and MD.
Collapse
Affiliation(s)
- Pablo Torterolo
- Department of Physiology, School of Medicine, Universidad de la República Montevideo, Uruguay
| | - Cecilia Scorza
- Department of Experimental Neuropharmacology, Instituto de Investigaciones Biológicas Clemente Estable Montevideo, Uruguay
| | - Patricia Lagos
- Department of Physiology, School of Medicine, Universidad de la República Montevideo, Uruguay
| | - Jessika Urbanavicius
- Department of Experimental Neuropharmacology, Instituto de Investigaciones Biológicas Clemente Estable Montevideo, Uruguay
| | - Luciana Benedetto
- Department of Physiology, School of Medicine, Universidad de la República Montevideo, Uruguay
| | - Claudia Pascovich
- Department of Physiology, School of Medicine, Universidad de la República Montevideo, Uruguay
| | - Ximena López-Hill
- Department of Experimental Neuropharmacology, Instituto de Investigaciones Biológicas Clemente Estable Montevideo, Uruguay
| | - Michael H Chase
- WebSciences International and University of California, Los Angeles School of Medicine Los Angeles, CA, USA
| | - Jaime M Monti
- Department of Pharmacology and Therapeutics, School of Medicine, Hospital de Clínicas, Universidad de la República Montevideo, Uruguay
| |
Collapse
|
18
|
Cui SY, Li SJ, Cui XY, Zhang XQ, Yu B, Sheng ZF, Huang YL, Cao Q, Xu YP, Lin ZG, Yang G, Song JZ, Ding H, Wang ZJ, Zhang YH. Phosphorylation of CaMKII in the rat dorsal raphe nucleus plays an important role in sleep-wake regulation. J Neurochem 2015; 136:609-19. [PMID: 26558357 DOI: 10.1111/jnc.13431] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Revised: 10/28/2015] [Accepted: 11/02/2015] [Indexed: 12/19/2022]
Abstract
The Ca(2+) modulation in the dorsal raphe nucleus (DRN) plays an important role in sleep-wake regulation. Calmodulin-dependent kinase II (CaMKII) is an important signal-transducing molecule that is activated by Ca(2+) . This study investigated the effects of intracellular Ca(2+) /CaMKII signaling in the DRN on sleep-wake states in rats. Maximum and minimum CaMKII phosphorylation was detected at Zeitgeber time 21 (ZT 21; wakefulness state) and ZT 3 (sleep state), respectively, across the light-dark rhythm in the DRN in rats. Six-hour sleep deprivation significantly reduced CaMKII phosphorylation in the DRN. Microinjection of the CAMKII activation inhibitor KN-93 (5 or 10 nmol) into the DRN suppressed wakefulness and enhanced rapid-eye-movement sleep (REMS) and non-REM sleep (NREMS). Application of a high dose of KN-93 (10 nmol) increased slow-wave sleep (SWS) time, SWS bouts, the mean duration of SWS, the percentage of SWS relative to total sleep, and delta power density during NREMS. Microinjection of CaCl2 (50 nmol) in the DRN increased CaMKII phosphorylation and decreased NREMS, SWS, and REMS. KN-93 abolished the inhibitory effects of CaCl2 on NREMS, SWS, and REMS. These data indicate a novel wake-promoting and sleep-suppressing role for the Ca(2+) /CaMKII signaling pathway in DRN neurons. We propose that the intracellular Ca(2+) /CaMKII signaling in the dorsal raphe nucleus (DRN) plays wake-promoting and sleep-suppressing role in rats. Intra-DRN application of KN-93 (CaMKII activation inhibitor) suppressed wakefulness and enhanced rapid-eye-movement sleep (REMS) and non-REMS (NREMS). Intra-DRN application of CaCl2 attenuated REMS and NREMS. We think these findings should provide a novel cellular and molecular mechanism of sleep-wake regulation.
Collapse
Affiliation(s)
- Su-Ying Cui
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Sheng-Jie Li
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Xiang-Yu Cui
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Xue-Qiong Zhang
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Bin Yu
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Zhao-Fu Sheng
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Yuan-Li Huang
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Qing Cao
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Ya-Ping Xu
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Zhi-Ge Lin
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Guang Yang
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Jin-Zhi Song
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Hui Ding
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Zi-Jun Wang
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| | - Yong-He Zhang
- Department of pharmacology, Peking University, School of Basic Medical Science, Beijing, China
| |
Collapse
|
19
|
Devera A, Pascovich C, Lagos P, Falconi A, Sampogna S, Chase MH, Torterolo P. Melanin-concentrating hormone (MCH) modulates the activity of dorsal raphe neurons. Brain Res 2015; 1598:114-28. [DOI: 10.1016/j.brainres.2014.12.032] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 12/09/2014] [Accepted: 12/13/2014] [Indexed: 12/27/2022]
|
20
|
Konadhode RR, Pelluru D, Shiromani PJ. Neurons containing orexin or melanin concentrating hormone reciprocally regulate wake and sleep. Front Syst Neurosci 2015; 8:244. [PMID: 25620917 PMCID: PMC4287014 DOI: 10.3389/fnsys.2014.00244] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 12/12/2014] [Indexed: 01/22/2023] Open
Abstract
Neurons containing orexin (hypocretin), or melanin concentrating hormone (MCH) are intermingled with each other in the perifornical and lateral hypothalamus. Each is a separate and distinct neuronal population, but they project to similar target areas in the brain. Orexin has been implicated in regulating arousal since loss of orexin neurons is associated with the sleep disorder narcolepsy. Microinjections of orexin into the brain or optogenetic stimulation of orexin neurons increase waking. Orexin neurons are active in waking and quiescent in sleep, which is consistent with their role in promoting waking. On the other hand, the MCH neurons are quiet in waking but active in sleep, suggesting that they could initiate sleep. Recently, for the first time the MCH neurons were stimulated optogenetically and it increased sleep. Indeed, optogenetic activation of MCH neurons induced sleep in both mice and rats at a circadian time when they should be awake, indicating the powerful effect that MCH neurons have in suppressing the wake-promoting effect of not only orexin but also of all of the other arousal neurotransmitters. Gamma-Aminobutyric acid (GABA) is coexpressed with MCH in the MCH neurons, although MCH is also inhibitory. The inhibitory tone of the MCH neurons is opposite to the excitatory tone of the orexin neurons. We hypothesize that strength in activity of each determines wake vs. sleep.
Collapse
Affiliation(s)
- Roda Rani Konadhode
- Departments of Psychiatry and Behavioral Sciences, Medical University of South Carolina Charleston, SC, USA
| | - Dheeraj Pelluru
- Departments of Psychiatry and Behavioral Sciences, Medical University of South Carolina Charleston, SC, USA
| | - Priyattam J Shiromani
- Departments of Psychiatry and Behavioral Sciences, Medical University of South Carolina Charleston, SC, USA ; Ralph H. Johnson VA Medical Center, Medical University of South Carolina Charleston, SC, USA
| |
Collapse
|
21
|
Parks GS, Olivas ND, Ikrar T, Sanathara NM, Wang L, Wang Z, Civelli O, Xu X. Histamine inhibits the melanin-concentrating hormone system: implications for sleep and arousal. J Physiol 2014; 592:2183-96. [PMID: 24639485 DOI: 10.1113/jphysiol.2013.268771] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Melanin-concentrating hormone (MCH)-producing neurons are known to regulate a wide variety of physiological functions such as feeding, metabolism, anxiety and depression, and reward. Recent studies have revealed that MCH neurons receive projections from several wake-promoting brain regions and are integral to the regulation of rapid eye movement (REM) sleep. Here, we provide evidence in both rats and mice that MCH neurons express histamine-3 receptors (H3R), but not histamine-1 (H1R) or histamine-2 (H2R) receptors. Electrophysiological recordings in brain slices from a novel line of transgenic mice that specifically express the reporter ZsGreen in MCH neurons show that histamine strongly inhibits MCH neurons, an effect which is TTX insensitive, and blocked by the intracellular presence of GDP-β-S. A specific H3R agonist, α-methylhistamine, mimicks the inhibitory effects of histamine, and a specific neutral H3R antagonist, VUF 5681, blocks this effect. Tertiapin Q (TPQ), a G protein-dependent inwardly rectifying potassium (GIRK) channel inhibitor, abolishes histaminergic inhibition of MCH neurons. These results indicate that histamine directly inhibits MCH neurons through H3R by activating GIRK channels and suggest that that inhibition of the MCH system by wake-active histaminergic neurons may be responsible for silencing MCH neurons during wakefulness and thus may be directly involved in the regulation of sleep and arousal.
Collapse
Affiliation(s)
- Gregory S Parks
- Department of Pharmacology, University of California Irvine, Irvine, CA, 92697, USA Department of Developmental and Cell Biology, University of California Irvine, Irvine, CA, 92697, USA
| | - Nicholas D Olivas
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, 92697, USA
| | - Taruna Ikrar
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, 92697, USA
| | - Nayna M Sanathara
- Department of Pharmacology, University of California Irvine, Irvine, CA, 92697, USA
| | - Lien Wang
- Department of Pharmacology, University of California Irvine, Irvine, CA, 92697, USA
| | - Zhiwei Wang
- Department of Pharmacology, University of California Irvine, Irvine, CA, 92697, USA
| | - Olivier Civelli
- Department of Pharmacology, University of California Irvine, Irvine, CA, 92697, USA Department of Developmental and Cell Biology, University of California Irvine, Irvine, CA, 92697, USA Department of Pharmaceutical Sciences, University of California Irvine, Irvine, CA, 92697, USA
| | - Xiangmin Xu
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, 92697, USA
| |
Collapse
|
22
|
Torterolo P, Chase MH. The hypocretins (orexins) mediate the "phasic" components of REM sleep: A new hypothesis. Sleep Sci 2014; 7:19-29. [PMID: 26483897 PMCID: PMC4521687 DOI: 10.1016/j.slsci.2014.07.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 01/27/2014] [Indexed: 12/17/2022] Open
Abstract
In 1998, a group of phenotypically distinct neurons were discovered in the postero-lateral hypothalamus which contained the neuropeptides hypocretin 1 and hypocretin 2 (also called orexin A and orexin B), which are excitatory neuromodulators. Hypocretinergic neurons project throughout the central nervous system and have been involved in the generation and maintenance of wakefulness. The sleep disorder narcolepsy, characterized by hypersomnia and cataplexy, is produced by degeneration of these neurons. The hypocretinergic neurons are active during wakefulness in conjunction with the presence of motor activity that occurs during survival-related behaviors. These neurons decrease their firing rate during non-REM sleep; however there is still controversy upon the activity and role of these neurons during REM sleep. Hence, in the present report we conducted a critical review of the literature of the hypocretinergic system during REM sleep, and hypothesize a possible role of this system in the generation of REM sleep.
Collapse
Affiliation(s)
- Pablo Torterolo
- Laboratorio de Neurobiología del Sueño, Departamento de Fisiología, Facultad de Medicina, Universidad de la República, General Flores 2125, 11800 Montevideo, Uruguay
| | - Michael H. Chase
- WebSciences International, Los Angeles, USA
- UCLA School of Medicine, Los Angeles, USA
| |
Collapse
|
23
|
Affiliation(s)
- Sonia Jego
- Douglas Institute, Department of Psychiatry, McGill University, Montreal, Canada
| | | |
Collapse
|
24
|
Wakefulness-promoting role of the inferior colliculus. Behav Brain Res 2013; 256:82-94. [DOI: 10.1016/j.bbr.2013.07.049] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 07/23/2013] [Accepted: 07/27/2013] [Indexed: 11/16/2022]
|
25
|
Jego S, Glasgow SD, Herrera CG, Ekstrand M, Reed SJ, Boyce R, Friedman J, Burdakov D, Adamantidis AR. Optogenetic identification of a rapid eye movement sleep modulatory circuit in the hypothalamus. Nat Neurosci 2013; 16:1637-43. [PMID: 24056699 PMCID: PMC4974078 DOI: 10.1038/nn.3522] [Citation(s) in RCA: 283] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 08/23/2013] [Indexed: 12/22/2022]
Abstract
Rapid-Eye Movement (REM) sleep correlates with neuronal activity in the brainstem, basal forebrain and lateral hypothalamus (LH). LH melanin-concentrating hormone (MCH)-expressing neurons are active during sleep, however, their action on REM sleep remains unclear. Using optogenetic tools in newly-generated Tg(Pmch-Cre) mice, we found that acute activation of MCH neurons (ChETA, SSFO) at the onset of REM sleep extended the duration of REM, but not non-REM sleep episode. In contrast, their acute silencing (eNpHR3.0, ArchT) reduced the frequency and amplitude of hippocampal theta rhythm, without affecting REM sleep duration. In vitro activation of MCH neuron terminals induced GABAA-mediated inhibitory post-synaptic currents (IPSCs) in wake-promoting histaminergic neurons of the tuberomammillary nucleus (TMN), while in vivo activation of MCH neuron terminals in TMN or medial septum also prolonged REM sleep episodes. Collectively, these results suggest that activation of MCH neurons maintains REM sleep, possibly through inhibition of arousal circuits in the mammalian brain.
Collapse
Affiliation(s)
- Sonia Jego
- Douglas Institute, Department of Psychiatry, McGill University, Montreal, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Monti JM, Torterolo P, Lagos P. Melanin-concentrating hormone control of sleep–wake behavior. Sleep Med Rev 2013; 17:293-8. [DOI: 10.1016/j.smrv.2012.10.002] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2012] [Revised: 10/06/2012] [Accepted: 10/08/2012] [Indexed: 01/16/2023]
|
27
|
Kátai Z, Adori C, Kitka T, Vas S, Kalmár L, Kostyalik D, Tóthfalusi L, Palkovits M, Bagdy G. Acute escitalopram treatment inhibits REM sleep rebound and activation of MCH-expressing neurons in the lateral hypothalamus after long term selective REM sleep deprivation. Psychopharmacology (Berl) 2013; 228:439-49. [PMID: 23515582 DOI: 10.1007/s00213-013-3046-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Accepted: 02/25/2013] [Indexed: 01/28/2023]
Abstract
RATIONALE Selective rapid eye movement sleep (REMS) deprivation using the platform-on-water ("flower pot") method causes sleep rebound with increased REMS, decreased REMS latency, and activation of the melanin-concentrating hormone (MCH) expressing neurons in the hypothalamus. MCH is implicated in the pathomechanism of depression regarding its influence on mood, feeding behavior, and REMS. OBJECTIVES We investigated the effects of the most selective serotonin reuptake inhibitor escitalopram on sleep rebound following REMS deprivation and, in parallel, on the activation of MCH-containing neurons. METHODS Escitalopram or vehicle (10 mg/kg, intraperitoneally) was administered to REMS-deprived (72 h) or home cage male Wistar rats. During the 3-h-long "rebound sleep", electroencephalography was recorded, followed by an MCH/Fos double immunohistochemistry. RESULTS During REMS rebound, the time spent in REMS and the number of MCH/Fos double-labeled neurons in the lateral hypothalamus increased markedly, and REMS latency showed a significant decrease. All these effects of REMS deprivation were significantly attenuated by escitalopram treatment. Besides the REMS-suppressing effects, escitalopram caused an increase in amount of and decrease in latency of slow wave sleep during the rebound. CONCLUSIONS These results show that despite the high REMS pressure caused by REMS deprivation procedure, escitalopram has the ability to suppress REMS rebound, as well as to diminish the activation of MCH-containing neurons, in parallel. Escitalopram caused a shift from REMS to slow wave sleep during the rebound. Furthermore, these data point to the potential connection between the serotonergic system and MCH in sleep regulation, which can be relevant in depression and in other mood disorders.
Collapse
Affiliation(s)
- Zita Kátai
- Department of Pharmacodynamics, Semmelweis University, 1089 Nagyvárad tér 4., Budapest, Hungary
| | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Lu ZH, Fukuda S, Minakawa Y, Yasuda A, Sakamoto H, Sawamura S, Takahashi H, Ishii N. Melanin concentrating hormone induces hippocampal acetylcholine release via the medial septum in rats. Peptides 2013; 44:32-9. [PMID: 23531605 DOI: 10.1016/j.peptides.2013.03.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 03/11/2013] [Accepted: 03/11/2013] [Indexed: 10/27/2022]
Abstract
Among various actions of melanin concentrating hormone (MCH), its memory function has been focused in animal studies. Although MCH neurons project to various areas in the brain, one main target site of MCH is hippocampal formation for memory consolidation. Recent immunohistochemical study shows that MCH neurons directly project to the hippocampal formation and may indirectly affect the hippocampus through the medial septum nucleus (MS). It has been reported that sleep is necessary for memory and that hippocampal acetylcholine (ACh) release is indispensable for memory consolidation. However, there is no report how MCH actually influences the hippocampal ACh effluxes in accordance with the sleep-wake cycle changes. Thus, we investigated the modulatory function of intracerebroventricular (icv) injection of MCH on the sleep-wake cycle and ACh release using microdialysis techniques. Icv injection of MCH significantly increased the rapid eye movement (REM) and non-REM episode time and the hippocampal, not cortical, ACh effluxes. There was a significant correlation between REM episode time and hippocampal ACh effluxes, but not between REM episode time and cortical ACh effluxes. Microinjection of MCH into the MS increased the hippocampal ACh effluxes with no influence on the REM episode time. It appears that the effect sites of icv MCH for prolongation of REM episode time may be other neuronal areas than the cholinergic neurons in the MS. We conclude that MCH actually increases the hippocampal ACh release at least in part through the MS in rats.
Collapse
Affiliation(s)
- Zhi-Hong Lu
- Department of Anesthesiology & Pain Medicine, Teikyo University School of Medicine, Tokyo, Japan
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Benedetto L, Rodriguez-Servetti Z, Lagos P, D'Almeida V, Monti JM, Torterolo P. Microinjection of melanin concentrating hormone into the lateral preoptic area promotes non-REM sleep in the rat. Peptides 2013; 39:11-5. [PMID: 23123302 DOI: 10.1016/j.peptides.2012.10.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 10/16/2012] [Accepted: 10/22/2012] [Indexed: 01/22/2023]
Abstract
The ventrolateral preoptic area (VLPO) has been recognized as one of the key structures responsible for the generation of non-REM (NREM) sleep. The melanin-concentrating hormone (MCH)-containing neurons, which are located in the lateral hypothalamus and incerto-hypothalamic area, project widely throughout the central nervous system and include projections to the VLPO. The MCH has been associated with the central regulation of feeding and energy homeostasis. In addition, recent findings strongly suggest that the MCHergic system promotes sleep. The aim of the present study was to determine if MCH generates sleep by regulating VLPO neuronal activity. To this purpose, we characterized the effect of unilateral and bilateral microinjections of MCH into the VLPO on sleep and wakefulness in the rat. Unilateral administration of MCH into the VLPO and adjacent dorsal preoptic area did not modify sleep. On the contrary, bilateral microinjections of MCH (100 ng) into these areas significantly increased light sleep (LS, 39.2±4.8 vs. 21.6±2.5 min, P<0.05) and total NREM sleep (142.4±23.2 vs. 86.5±10.5 min, P<0.05) compared to control (saline) microinjections. No effect was observed on REM sleep. We conclude that MCH administration into the VLPO and adjacent dorsal lateral preoptic area promotes the generation of NREM sleep.
Collapse
Affiliation(s)
- Luciana Benedetto
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | | | | | | | | | | |
Collapse
|
30
|
Microinjection of the melanin-concentrating hormone into the lateral basal forebrain increases REM sleep and reduces wakefulness in the rat. Life Sci 2012; 90:895-9. [PMID: 22579511 DOI: 10.1016/j.lfs.2012.04.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 02/27/2012] [Accepted: 04/13/2012] [Indexed: 10/28/2022]
Abstract
AIMS To examine the effects of bilateral microinjection of melanin-concentrating hormone (MCH) 50 and 100 ng into the horizontal limb of the diagonal band of Broca (HDB) on sleep variables during the light phase of the light-dark cycle of the rat. MAIN METHODS Male Wistar rats were implanted for chronic sleep recordings. In addition, a guide cannula was implanted above the right and left HDB. Following the microinjection of MCH or control solution the electroencephalogram and the electromyogram were recorded for 6 h. Data was collected and classified as either wakefulness (W), light sleep, slow wave sleep (SWS) or REM sleep (REMS). Latencies for SWS and REMS, as well as the number of REM periods and the mean duration of REM episodes were also determined. KEY FINDINGS MCH 50 and 100 ng significantly decreased W during the first 2-h of recording. Moreover, MCH 100 ng significantly reduced REMS latency and increased REMS time during the first 2-h block of the recording, due to an increase in the number of REM periods. SIGNIFICANCE Our findings tend to suggest that the basal forebrain participates in the effects of MCH on W and REMS through the deactivation of cholinergic, glutamatergic and γ-aminobutyric acid (GABA)-ergic cells.
Collapse
|
31
|
Pérez Sirkin DI, Cánepa MM, Fossati M, Fernandino JI, Delgadin T, Canosa LF, Somoza GM, Vissio PG. Melanin concentrating hormone (MCH) is involved in the regulation of growth hormone in Cichlasoma dimerus (Cichlidae, Teleostei). Gen Comp Endocrinol 2012; 176:102-11. [PMID: 22266076 DOI: 10.1016/j.ygcen.2012.01.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Revised: 12/13/2011] [Accepted: 01/03/2012] [Indexed: 01/05/2023]
Abstract
Growth hormone (GH) is the main pituitary hormone involved in somatic growth. In fish, the neuroendocrine control of GH is multifactorial due to the interaction of multiple inhibitors and stimulators. Melanin-concentrating hormone (MCH) is a cyclic peptide involved in skin color regulation of fish. In addition, MCH has been related to the regulation of food intake in both mammals and fish. There is only one report presenting evidences on the GH release stimulation by MCH in mammals in experiments in vitro, but there are no data on non-mammals. In the present work, we report for the first time the sequence of MCH and GH cDNA in Cichlasoma dimerus, a freshwater South American cichlid fish. We detected contacts between MCH fibers and GH cells in the proximal pars distalis region of the pituitary gland by double label confocal immunofluorescence indicating a possible functional relationship. Besides, we found that MCH increased GH transcript levels and stimulated GH release in pituitary cultures. Additionally, C. dimerus exposed to a white background had a greater number of MCH neurons with a larger nuclear area and higher levels of MCH transcript than those fish exposed to a black background. Furthermore, fish reared for 3 months in a white background showed a greater body weight and total length compared to those from black background suggesting that MCH might be related to somatic growth in C. dimerus. Our results report for the first time, that MCH is involved in the regulation of the synthesis and release of GH in vitro in C. dimerus, and probably in the fish growth rate.
Collapse
Affiliation(s)
- D I Pérez Sirkin
- Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina
| | | | | | | | | | | | | | | |
Collapse
|
32
|
Torterolo P, Lagos P, Monti JM. Melanin-concentrating hormone: a new sleep factor? Front Neurol 2011; 2:14. [PMID: 21516258 PMCID: PMC3080035 DOI: 10.3389/fneur.2011.00014] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 03/02/2011] [Indexed: 12/18/2022] Open
Abstract
Neurons containing the neuropeptide melanin-concentrating hormone (MCH) are mainly located in the lateral hypothalamus and the incerto-hypothalamic area, and have widespread projections throughout the brain. While the biological functions of this neuropeptide are exerted in humans through two metabotropic receptors, the MCHR1 and MCHR2, only the MCHR1 is present in rodents. Recently, it has been shown that the MCHergic system is involved in the control of sleep. We can summarize the experimental findings as follows: (1) The areas related to the control of sleep and wakefulness have a high density of MCHergic fibers and receptors. (2) MCHergic neurons are active during sleep, especially during rapid eye movement (REM) sleep. (3) MCH knockout mice have less REM sleep, notably under conditions of negative energy balance. Animals with genetically inactivated MCHR1 also exhibit altered vigilance state architecture and sleep homeostasis. (4) Systemically administered MCHR1 antagonists reduce sleep. (5) Intraventricular microinjection of MCH increases both slow wave sleep (SWS) and REM sleep; however, the increment in REM sleep is more pronounced. (6) Microinjection of MCH into the dorsal raphe nucleus increases REM sleep time. REM seep is inhibited by immunoneutralization of MCH within this nucleus. (7) Microinjection of MCH in the nucleus pontis oralis of the cat enhances REM sleep time and reduces REM sleep latency. All these data strongly suggest that MCH has a potent role in the promotion of sleep. Although both SWS and REM sleep are facilitated by MCH, REM sleep seems to be more sensitive to MCH modulation.
Collapse
Affiliation(s)
- Pablo Torterolo
- Department of Physiology, School of Medicine, University of the Republic Montevideo, Uruguay
| | | | | |
Collapse
|