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Grujic N, Polania R, Burdakov D. Neurobehavioral meaning of pupil size. Neuron 2024:S0896-6273(24)00406-9. [PMID: 38925124 DOI: 10.1016/j.neuron.2024.05.029] [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: 11/24/2023] [Revised: 03/22/2024] [Accepted: 05/31/2024] [Indexed: 06/28/2024]
Abstract
Pupil size is a widely used metric of brain state. It is one of the few signals originating from the brain that can be readily monitored with low-cost devices in basic science, clinical, and home settings. It is, therefore, important to investigate and generate well-defined theories related to specific interpretations of this metric. What exactly does it tell us about the brain? Pupils constrict in response to light and dilate during darkness, but the brain also controls pupil size irrespective of luminosity. Pupil size fluctuations resulting from ongoing "brain states" are used as a metric of arousal, but what is pupil-linked arousal and how should it be interpreted in neural, cognitive, and computational terms? Here, we discuss some recent findings related to these issues. We identify open questions and propose how to answer them through a combination of well-defined tasks, neurocomputational models, and neurophysiological probing of the interconnected loops of causes and consequences of pupil size.
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Affiliation(s)
- Nikola Grujic
- Neurobehavioural Dynamics Lab, ETH Zürich, Department of Health Sciences and Technology, Schorenstrasse 16, 8603 Schwerzenbach, Switzerland.
| | - Rafael Polania
- Decision Neuroscience Lab, ETH Zürich, Department of Health Sciences and Technology, Winterthurstrasse 190, 8057 Zürich, Switzerland
| | - Denis Burdakov
- Neurobehavioural Dynamics Lab, ETH Zürich, Department of Health Sciences and Technology, Schorenstrasse 16, 8603 Schwerzenbach, Switzerland.
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2
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Feng H, Qiao QC, Luo QF, Zhou JY, Lei F, Chen Y, Wen SY, Chen WH, Pang YJ, Hu ZA, Jiang YB, Zhang XY, Zhou TY, Zhang XY, Yang N, Zhang J, Hu R. Orexin Neurons to Sublaterodorsal Tegmental Nucleus Pathway Prevents Sleep Onset REM Sleep-Like Behavior by Relieving the REM Sleep Pressure. RESEARCH (WASHINGTON, D.C.) 2024; 7:0355. [PMID: 38694202 PMCID: PMC11062508 DOI: 10.34133/research.0355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Accepted: 03/25/2024] [Indexed: 05/04/2024]
Abstract
Proper timing of vigilance states serves fundamental brain functions. Although disturbance of sleep onset rapid eye movement (SOREM) sleep is frequently reported after orexin deficiency, their causal relationship still remains elusive. Here, we further study a specific subgroup of orexin neurons with convergent projection to the REM sleep promoting sublaterodorsal tegmental nucleus (OXSLD neurons). Intriguingly, although OXSLD and other projection-labeled orexin neurons exhibit similar activity dynamics during REM sleep, only the activation level of OXSLD neurons exhibits a significant positive correlation with the post-inter-REM sleep interval duration, revealing an essential role for the orexin-sublaterodorsal tegmental nucleus (SLD) neural pathway in relieving REM sleep pressure. Monosynaptic tracing reveals that multiple inputs may help shape this REM sleep-related dynamics of OXSLD neurons. Genetic ablation further shows that the homeostatic architecture of sleep/wakefulness cycles, especially avoidance of SOREM sleep-like transition, is dependent on this activity. A positive correlation between the SOREM sleep occurrence probability and depression states of narcoleptic patients further demonstrates the possible significance of the orexin-SLD pathway on REM sleep homeostasis.
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Affiliation(s)
- Hui Feng
- Department of Neurobiology,
Army Medical University, 400038 Chongqing, P.R. China
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Army Medical University, 400038 Chongqing, P.R. China
| | - Qi-Cheng Qiao
- Department of Physiology,
Army Medical University, 400038 Chongqing, P.R. China
| | - Qi-Fa Luo
- Department of Physiology,
Army Medical University, 400038 Chongqing, P.R. China
| | - Jun-Ying Zhou
- Sleep Medicine Center, West China Hospital,
Sichuan University, 610000 Chengdu, Sichuan, P.R. China
| | - Fei Lei
- Sleep Medicine Center, West China Hospital,
Sichuan University, 610000 Chengdu, Sichuan, P.R. China
| | - Yao Chen
- Department of Physiology,
Army Medical University, 400038 Chongqing, P.R. China
| | - Si-Yi Wen
- Department of Physiology,
Army Medical University, 400038 Chongqing, P.R. China
| | - Wen-Hao Chen
- Department of Physiology,
Army Medical University, 400038 Chongqing, P.R. China
| | - Yu-Jie Pang
- Department of Physiology,
Army Medical University, 400038 Chongqing, P.R. China
| | - Zhi-An Hu
- Department of Physiology,
Army Medical University, 400038 Chongqing, P.R. China
| | - Yi-Bin Jiang
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Army Medical University, 400038 Chongqing, P.R. China
| | - Xu-Yang Zhang
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Army Medical University, 400038 Chongqing, P.R. China
| | - Teng-Yuan Zhou
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Army Medical University, 400038 Chongqing, P.R. China
| | - Xin-Yan Zhang
- Sleep Medicine Center, West China Hospital,
Sichuan University, 610000 Chengdu, Sichuan, P.R. China
| | - Nian Yang
- Department of Physiology,
Army Medical University, 400038 Chongqing, P.R. China
| | - Jun Zhang
- Department of Neurobiology,
Army Medical University, 400038 Chongqing, P.R. China
- Department of Physiology,
Army Medical University, 400038 Chongqing, P.R. China
| | - Rong Hu
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Army Medical University, 400038 Chongqing, P.R. China
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3
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Leino TO, Turku A, Urvas L, Adhikari K, Oksanen J, Steynen Y, Yli-Kauhaluoma J, Xhaard H, Kukkonen JP, Wallén EAA. Azulene as a biphenyl mimetic in orexin/hypocretin receptor agonists. Bioorg Med Chem 2023; 88-89:117325. [PMID: 37209639 DOI: 10.1016/j.bmc.2023.117325] [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: 02/02/2023] [Revised: 04/26/2023] [Accepted: 05/05/2023] [Indexed: 05/22/2023]
Abstract
Azulene is a rare ring structure in drugs, and we investigated whether it could be used as a biphenyl mimetic in known orexin receptor agonist Nag 26, which is binding to both orexin receptors OX1 and OX2 with preference towards OX2. The most potent azulene-based compound was identified as an OX1 orexin receptor agonist (pEC50 = 5.79 ± 0.07, maximum response = 81 ± 8% (s.e.m. of five independent experiments) of the maximum response to orexin-A in Ca2+ elevation assay). However, the azulene ring and the biphenyl scaffold are not identical in their spatial shape and electron distribution, and their derivatives may adopt different binding modes in the binding site.
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Affiliation(s)
- Teppo O Leino
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 University of Helsinki, Finland; Department of Chemistry and NanoScience Center, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland.
| | - Ainoleena Turku
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 University of Helsinki, Finland; Department of Veterinary Biosciences, Faculty of Veterinary Medicine, University of Helsinki, P.O. Box 66, FI-00014 University of Helsinki, Finland
| | - Lauri Urvas
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 University of Helsinki, Finland; Department of Pharmacology, Faculty of Medicine, University of Helsinki, P.O. Box 63, FI-00014 University of Helsinki, Finland
| | - Karuna Adhikari
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 University of Helsinki, Finland
| | - Jouni Oksanen
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 University of Helsinki, Finland
| | - Yana Steynen
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 University of Helsinki, Finland
| | - Jari Yli-Kauhaluoma
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 University of Helsinki, Finland
| | - Henri Xhaard
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 University of Helsinki, Finland
| | - Jyrki P Kukkonen
- Department of Veterinary Biosciences, Faculty of Veterinary Medicine, University of Helsinki, P.O. Box 66, FI-00014 University of Helsinki, Finland; Department of Pharmacology, Faculty of Medicine, University of Helsinki, P.O. Box 63, FI-00014 University of Helsinki, Finland
| | - Erik A A Wallén
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 University of Helsinki, Finland
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4
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Kołosowska K, Lehner M, Skórzewska A, Gawryluk A, Tomczuk F, Sobolewska A, Turzyńska D, Liguz-Lęcznar M, Bednarska-Makaruk M, Maciejak P, Wisłowska-Stanek A. Molecular pattern of a decrease in the rewarding effect of cocaine after an escalating-dose drug regimen. Pharmacol Rep 2023; 75:85-98. [PMID: 36586075 PMCID: PMC9889529 DOI: 10.1007/s43440-022-00443-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/06/2022] [Accepted: 12/19/2022] [Indexed: 01/01/2023]
Abstract
BACKGROUND Long-term cocaine exposure leads to dysregulation of the reward system and initiates processes that ultimately weaken its rewarding effects. Here, we studied the influence of an escalating-dose cocaine regimen on drug-associated appetitive behavior after a withdrawal period, along with corresponding molecular changes in plasma and the prefrontal cortex (PFC). METHODS We applied a 5 day escalating-dose cocaine regimen in rats. We assessed anxiety-like behavior at the beginning of the withdrawal period in the elevated plus maze (EPM) test. The reinforcement properties of cocaine were evaluated in the Conditioned Place Preference (CPP) test along with ultrasonic vocalization (USV) in the appetitive range in a drug-associated context. We assessed corticosterone, proopiomelanocortin (POMC), β-endorphin, CART 55-102 levels in plasma (by ELISA), along with mRNA levels for D2 dopaminergic receptor (D2R), κ-receptor (KOR), orexin 1 receptor (OX1R), CART 55-102, and potential markers of cocaine abuse: miRNA-124 and miRNA-137 levels in the PFC (by PCR). RESULTS Rats subjected to the escalating-dose cocaine binge regimen spent less time in the cocaine-paired compartment, and presented a lower number of appetitive USV episodes. These changes were accompanied by a decrease in corticosterone and CART levels, an increase in POMC and β-endorphin levels in plasma, and an increase in the mRNA for D2R and miRNA-124 levels, but a decrease in the mRNA levels for KOR, OX1R, and CART 55-102 in the PFC. CONCLUSIONS The presented data reflect a part of a bigger picture of a multilevel interplay between neurotransmitter systems and neuromodulators underlying processes associated with cocaine abuse.
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Affiliation(s)
- Karolina Kołosowska
- grid.418955.40000 0001 2237 2890Department of Neurochemistry, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland
| | - Małgorzata Lehner
- grid.418955.40000 0001 2237 2890Department of Neurochemistry, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland
| | - Anna Skórzewska
- grid.418955.40000 0001 2237 2890Department of Neurochemistry, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland
| | - Aleksandra Gawryluk
- grid.419305.a0000 0001 1943 2944Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Filip Tomczuk
- grid.418955.40000 0001 2237 2890Department of Genetics, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland
| | - Alicja Sobolewska
- grid.418955.40000 0001 2237 2890Department of Neurochemistry, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland
| | - Danuta Turzyńska
- grid.418955.40000 0001 2237 2890Department of Neurochemistry, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland
| | - Monika Liguz-Lęcznar
- grid.419305.a0000 0001 1943 2944Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Małgorzata Bednarska-Makaruk
- grid.418955.40000 0001 2237 2890Department of Genetics, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland
| | - Piotr Maciejak
- grid.418955.40000 0001 2237 2890Department of Neurochemistry, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland
| | - Aleksandra Wisłowska-Stanek
- grid.13339.3b0000000113287408Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Centre for Preclinical Research and Technology (CePT), 1B Banacha Street, 02-097 Warsaw, Poland
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5
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Arthaud S, Villalba M, Blondet C, Morel AL, Peyron C. Effects of sex and estrous cycle on sleep and cataplexy in narcoleptic mice. Sleep 2022; 45:6569391. [DOI: 10.1093/sleep/zsac089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 03/10/2022] [Indexed: 11/14/2022] Open
Abstract
Abstract
Narcolepsy type 1 (NT1) is a rare neurology disorder caused by the loss of orexin/hypocretin neurons. NT1 is characterized by excessive daytime sleepiness, sleep and wake fragmentation, and cataplexy. These symptoms have been equally described in both women and men, although influences of gender and hormonal cycles have been poorly studied. Unfortunately, most studies with NT1 preclinical mouse models, use only male mice to limit potential variations due to the hormonal cycle. Therefore, whether gender and/or hormonal cycles impact the expression of narcoleptic symptoms remains to be determined. To address this question, we analyzed vigilance states and cataplexy in 20 female and 17 male adult orexin knock-out narcoleptic mice, with half of the females being recorded over multiple days. Mice had access to chocolate to encourage the occurrence of cataplectic episodes. A vaginal smear was performed daily in female mice to establish the state of the estrous cycle (EC) of the previous recorded night. We found that vigilance states were more fragmented in males than females, and that females had less paradoxical sleep (p = 0.0315) but more cataplexy (p = 0.0375). Interestingly, sleep and wake features were unchanged across the female EC, but the total amount of cataplexy was doubled during estrus compared to other stages of the cycle (p = 0.001), due to a large increase in the number of cataplexy episodes (p = 0.0002). Altogether these data highlight sex differences in the expression of narcolepsy symptoms in orexin knock-out mice. Notably, cataplexy occurrence was greatly influenced by estrous cycle. Whether it is due to hormonal changes would need to be further explored.
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Affiliation(s)
- Sébastien Arthaud
- Center for Research in Neuroscience of Lyon (CRNL), SLEEP Team, CNRS UMR 5292, INSERM U1028, Centre Hospitalier le Vinatier—Bâtiment 462—Neurocampus Michel Jouvet , Bron Cedex , France
- University Lyon1 , Lyon , France
| | - Manon Villalba
- Center for Research in Neuroscience of Lyon (CRNL), SLEEP Team, CNRS UMR 5292, INSERM U1028, Centre Hospitalier le Vinatier—Bâtiment 462—Neurocampus Michel Jouvet , Bron Cedex , France
- University Lyon1 , Lyon , France
| | | | - Anne-Laure Morel
- Center for Research in Neuroscience of Lyon (CRNL), SLEEP Team, CNRS UMR 5292, INSERM U1028, Centre Hospitalier le Vinatier—Bâtiment 462—Neurocampus Michel Jouvet , Bron Cedex , France
- University Lyon1 , Lyon , France
| | - Christelle Peyron
- Center for Research in Neuroscience of Lyon (CRNL), SLEEP Team, CNRS UMR 5292, INSERM U1028, Centre Hospitalier le Vinatier—Bâtiment 462—Neurocampus Michel Jouvet , Bron Cedex , France
- University Lyon1 , Lyon , France
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6
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Spinieli RL, Ben Musa R, Cornelius-Green J, Hasser EM, Cummings KJ. Orexin facilitates the ventilatory and behavioral responses of rats to hypoxia. Am J Physiol Regul Integr Comp Physiol 2022; 322:R581-R596. [PMID: 35380477 PMCID: PMC9109809 DOI: 10.1152/ajpregu.00334.2021] [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] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 03/22/2022] [Accepted: 03/30/2022] [Indexed: 02/03/2023]
Abstract
Orexin neurons are sensitive to CO2 and contribute to cardiorespiratory homeostasis as well as sensorimotor control. Whether orexin facilitates respiratory and behavioral responses to acute hypoxia is unclear. We hypothesized that orexin neurons are activated by acute hypoxia and that orexin facilitates the hypoxic ventilatory response (HVR), as well as the arterial blood pressure (ABP) and behavioral (movement) responses to acute hypoxia. We further hypothesized that orexin has greater effects in the active phase of the rat circadian cycle, when orexin neurons have high activity. Using whole body plethysmography with EEG, EMG, and the dual-orexin receptor (OxR) antagonist suvorexant (20 mg/kg ip), we determined the effect of OxR blockade on the respiratory, ABP, and behavioral responses of adult rats to acute, graded hypoxia ([Formula: see text]= 0.15, 0.13, 0.11, and 0.09) and hyperoxic hypercapnia ([Formula: see text]= 0.05; [Formula: see text]= 0.95). OxR blockade had no effect on eupnea. OxR blockade significantly reduced the HVR in both inactive and active phases, with a stronger effect in the active phase. OxR blockade reduced the behavioral response to acute hypoxia in the active phase. The central component of the ventilatory and the ABP responses to hypercapnia were reduced by OxR blockade solely in the inactive phase. In the inactive phase, hypoxia activated ∼10% of orexin neurons in the perifornical hypothalamus. These data suggest that orexin neurons participate in the peripheral chemoreflex to facilitate the ventilatory and behavioral responses to acute hypoxia in rats, particularly in the active phase. Orexin also facilitates central chemoreflex responses to CO2 in the inactive phase.
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Affiliation(s)
- Richard L Spinieli
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, Missouri
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| | - Ruwaida Ben Musa
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, Missouri
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| | - Jennifer Cornelius-Green
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, Missouri
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| | - Eileen M Hasser
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, Missouri
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| | - Kevin J Cummings
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, Missouri
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
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7
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Agrawal S, Singh V, Singh C, Singh A. A review on pathophysiological aspects of Sleep Deprivation. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2022; 22:CNSNDDT-EPUB-123413. [PMID: 35549867 DOI: 10.2174/1871527321666220512092718] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 11/08/2021] [Accepted: 01/16/2022] [Indexed: 11/22/2022]
Abstract
Sleep deprivation (SD) (also referred as insomnia) is a condition in which peoples fails to get enough sleep due to excessive yawning, facing difficulty to learn new concepts, forgetfulness as well as depressed mood. This could be occurs due to several possible reasons including medications, stress (caused by shift work). Despite the fact that sleep is important for the normal physiology, it currently affects millions of people around the world US (70 million) and Europe (45 million). Due to increase work demand nowadays lots of peoples experiencing sleep deprivation hence, this could be the reason for several car accident followed by death and morbidity. This review highlighted the impact of SD on neurotransmitter release and functions, theories (Flip-flop theory, oxidative stress theory, neuroinflammation theory, neurotransmitter theory, and hormonal theory) associated with SD pathogenesis apart from this it also demonstrate the molecular pathways underlying SD (PI3K and Akt , NF-κB, Nrf2, and adenosine pathway. However, this study also elaborates the SD induced changes in the level of neurotransmitters, hormonal, and mitochondrial functions. Along with this, it also covers several molecular aspects associated with SD as well. Through this study a link is made between SD and associated causes, which will further help to develop potential therapeutic strategy against SD.
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Affiliation(s)
- Shelly Agrawal
- Affiliated to IK Gujral Punjab Technical University Jalandhar, Punjab, India
| | - Vishesh Singh
- Affiliated to IK Gujral Punjab Technical University Jalandhar, Punjab, India
| | - Charan Singh
- Affiliated to IK Gujral Punjab Technical University Jalandhar, Punjab, India
| | - Arti Singh
- Affiliated to IK Gujral Punjab Technical University Jalandhar, Punjab, India
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8
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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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9
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Melzi S, Morel AL, Scoté-Blachon C, Liblau R, Dauvilliers Y, Peyron C. Histamine in murine narcolepsy: What do genetic and immune models tell us? Brain Pathol 2021; 32:e13027. [PMID: 34672414 PMCID: PMC8877734 DOI: 10.1111/bpa.13027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 09/14/2021] [Accepted: 09/27/2021] [Indexed: 12/20/2022] Open
Abstract
An increased number of histaminergic neurons, identified by labeling histidine‐decarboxylase (HDC) its synthesis enzyme, was unexpectedly found in patients with narcolepsy type 1 (NT1). In quest for enlightenment, we evaluate whether an increase in HDC cell number and expression level would be detected in mouse models of the disease, in order to provide proof of concepts reveling possible mechanisms of compensation for the loss of orexin neurons, and/or of induced expression as a consequence of local neuroinflammation, a state that likely accompanies NT1. To further explore the compensatory hypothesis, we also study the noradrenergic wake‐promoting system. Immunohistochemistry for HDC, orexin, and melanin‐concentrating hormone (MCH) was used to count neurons. Quantitative‐PCR of HDC, orexin, MCH, and tyrosine‐hydroxylase was performed to evaluate levels of mRNA expression in the hypothalamus or the dorsal pons. Both quantifications were achieved in genetic and neuroinflammatory models of narcolepsy with major orexin impairment, namely the orexin‐deficient (Orex‐KO) and orexin‐hemagglutinin (Orex‐HA) mice respectively. The number of HDC neurons and mRNA expression level were unchanged in Orex‐KO mice compared to controls. Similarly, we found no change in tyrosine‐hydroxylase mRNA expression in the dorsal pons between groups. Further, despite the presence of protracted local neuroinflammation as witnessed by the presence of reactive microglia, we found no change in the number of neurons nor the expression of HDC in Orex‐HA mice compared to controls. Importantly, no correlation was found in all conditions between HDC and orexin. Our findings indicate that, in mice, the expression of histamine and noradrenalin, two wake‐promoting systems, are not modulated by orexin level whether the lack of orexin is constitutive or induced at adult age, showing thus no compensation. They also show no recruitment of histamine by local neuroinflammation. Further studies will be needed to further define the role of histamine in the pathophysiology of NT1.
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Affiliation(s)
- Silvia Melzi
- Sleep Team, Center for Research in Neuroscience of LYON, CNRS UMR5292, INSERM U1028, University of Lyon1, Bron, France
| | - Anne-Laure Morel
- Sleep Team, Center for Research in Neuroscience of LYON, CNRS UMR5292, INSERM U1028, University of Lyon1, Bron, France
| | - Céline Scoté-Blachon
- Functional Neurogenetics platform, Center for Research in Neuroscience of LYON, CNRS UMR5292, INSERM U1028, University of Lyon1, Bron, France
| | - Roland Liblau
- Toulouse Institute for Infectious and Inflammatory diseases, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, UPS, University of Toulouse, Toulouse, France
| | - Yves Dauvilliers
- National Reference Centre for Orphan Diseases, Narcolepsy - Rare hypersomnia, Sleep Unit, Department of Neurology, CHU Montpellier, Institute for Neuroscience of Montpellier INM, INSERM U1298, University of Montpellier, Montpellier, France
| | - Christelle Peyron
- Sleep Team, Center for Research in Neuroscience of LYON, CNRS UMR5292, INSERM U1028, University of Lyon1, Bron, France
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10
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Bátora D, Zsigmond Á, Lőrincz IZ, Szegvári G, Varga M, Málnási-Csizmadia A. Subcellular Dissection of a Simple Neural Circuit: Functional Domains of the Mauthner-Cell During Habituation. Front Neural Circuits 2021; 15:648487. [PMID: 33828462 PMCID: PMC8019725 DOI: 10.3389/fncir.2021.648487] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 02/23/2021] [Indexed: 11/13/2022] Open
Abstract
Sensorimotor integration is a pivotal feature of the nervous system for ensuring a coordinated motor response to external stimuli. In essence, such neural circuits can optimize behavioral performance based on the saliency of environmental cues. In zebrafish, habituation of the acoustic startle response (ASR) is a simple behavior integrated into the startle command neurons, called the Mauthner cells. Whereas the essential neuronal components that regulate the startle response have been identified, the principles of how this regulation is integrated at the subcellular regions of the Mauthner cell, which in turn modulate the performance of the behavior, is still not well understood. Here, we reveal mechanistically distinct dynamics of excitatory inputs converging onto the lateral dendrite (LD) and axon initial segment (AIS) of the Mauthner cell by in vivo imaging glutamate release using iGluSnFR, an ultrafast glutamate sensing fluorescent reporter. We find that modulation of glutamate release is dependent on NMDA receptor activity exclusively at the AIS, which is responsible for setting the sensitivity of the startle reflex and inducing a depression of synaptic activity during habituation. In contrast, glutamate-release at the LD is not regulated by NMDA receptors and serves as a baseline component of Mauthner cell activation. Finally, using in vivo calcium imaging at the feed-forward interneuron population component of the startle circuit, we reveal that these cells indeed play pivotal roles in both setting the startle threshold and habituation by modulating the AIS of the Mauthner cell. These results indicate that a command neuron may have several functionally distinct regions to regulate complex aspects of behavior.
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Affiliation(s)
- Dániel Bátora
- MTA-ELTE Motor Pharmacology Research Group, Budapest, Hungary
| | | | | | - Gábor Szegvári
- MTA-ELTE Motor Pharmacology Research Group, Budapest, Hungary
| | | | - András Málnási-Csizmadia
- MTA-ELTE Motor Pharmacology Research Group, Budapest, Hungary.,Motorpharma Limited, Budapest, Hungary
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11
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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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12
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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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13
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Cheng J, Wu F, Zhang M, Ding D, Fan S, Chen G, Zhang J, Wang L. The Interaction Between the Ventrolateral Preoptic Nucleus and the Tuberomammillary Nucleus in Regulating the Sleep-Wakefulness Cycle. Front Neurosci 2021; 14:615854. [PMID: 33381012 PMCID: PMC7767984 DOI: 10.3389/fnins.2020.615854] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 11/20/2020] [Indexed: 11/20/2022] Open
Abstract
The ventrolateral preoptic nucleus (VLPO) in the anterior hypothalamus and the tuberomammillary nucleus (TMN) in the posterior hypothalamus are critical regions which involve the regulation of sleep-wakefulness flip-flop in the central nervous system. Most of the VLPO neurons are sleep-promoting neurons, which co-express γ-aminobutyric acid (GABA) and galanin, while TMN neurons express histamine (HA), a key wake-promoting neurotransmitter. Previous studies have shown that the two regions are innervated between each other, but how to regulate the sleep-wake cycle are not yet clear. Here, bicuculline (Bic), a GABAA-receptor antagonist, L-glutamate (L-Glu), an excitatory neurotransmitter, and triprolidine (Trip), a HA1 receptor (HRH1) inhibitor, were bilaterally microinjected into TMN or VLPO after surgically implanting the electroencephalogram (EEG) and electromyography (EMG) electrode recording system. Microinjecting L-Glu into VLPO during the night significantly increased the NREM sleep time, and this phenomenon was weakened after selectively blocking GABAA receptors with Bic microinjected into TMN. Those results reveal that VLPO neurons activated, which may inhibit TMN neurons inducing sleep via GABAA receptors. On the contrary, exciting TMN neurons by L-Glu during the day, the wakefulness time was significantly increased. These phenomena were reversed by blocking HRH1 with Trip microinjected into VLPO. Those results reveal that TMN neuron activating may manipulate VLPO neurons via HRH1, and induce wakefulness. In conclusion, VLPO GABAergic neurons and TMN histaminergic neurons may interact with each other in regulating the sleep-wake cycle.
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Affiliation(s)
- Juan Cheng
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Fang Wu
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,Teaching and Research Office of Physiology, School of Basic Medical Sciences, Anhui Medical College, Hefei, China
| | - Mingrui Zhang
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Ding Ding
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,Teaching and Research Office of Physiology, School of Basic Medical Sciences, Anhui Medical College, Hefei, China
| | - Sumei Fan
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Guihai Chen
- The Affiliated Chaohu Hospital, Anhui Medical University, Hefei, China
| | - Jin Zhang
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,Department of Neurology, Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Liecheng Wang
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
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14
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Zeitzer JM. The neurobiological underpinning of the circadian wake signal. Biochem Pharmacol 2020; 191:114386. [PMID: 33359009 DOI: 10.1016/j.bcp.2020.114386] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/16/2020] [Accepted: 12/17/2020] [Indexed: 12/27/2022]
Abstract
The circadian wake drive is a mathematic representation of the observed increased propensity to stay awake late in the day, peaking in the hours just before anticipated bed time. It has been called the "forbidden zone" due to the difficulty in initiating sleep during this time and is responsible for the problems initiating sleep when traveling eastward, for maintaining daytime sleep in shift workers, and for initiating sleep in some individuals with insomnia. Evidence culled from studies in individuals with narcolepsy, who lack production of hypocretin (orexin) neuropeptides, as well as a primate model of human wake consolidation and pharmacologic studies of hypocretin antagonists indicate that hypocretin-1 may be the physiologic instantiation of the circadian wake drive. This review will discuss the evidence in support of this hypothesis.
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Affiliation(s)
- Jamie M Zeitzer
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, United States; Mental Illness Research Education and Clinical Center, VA Palo Alto Health Care System, 3801 Miranda Avenue (151Y), Palo Alto, CA 94304, United States.
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15
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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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16
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Fast sensory representations in the lateral hypothalamus and their roles in brain function. Physiol Behav 2020; 222:112952. [DOI: 10.1016/j.physbeh.2020.112952] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 03/26/2020] [Accepted: 04/28/2020] [Indexed: 01/12/2023]
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17
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Feng H, Wen SY, Qiao QC, Pang YJ, Wang SY, Li HY, Cai J, Zhang KX, Chen J, Hu ZA, Luo FL, Wang GZ, Yang N, Zhang J. Orexin signaling modulates synchronized excitation in the sublaterodorsal tegmental nucleus to stabilize REM sleep. Nat Commun 2020; 11:3661. [PMID: 32694504 PMCID: PMC7374574 DOI: 10.1038/s41467-020-17401-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 06/24/2020] [Indexed: 11/30/2022] Open
Abstract
The relationship between orexin/hypocretin and rapid eye movement (REM) sleep remains elusive. Here, we find that a proportion of orexin neurons project to the sublaterodorsal tegmental nucleus (SLD) and exhibit REM sleep-related activation. In SLD, orexin directly excites orexin receptor-positive neurons (occupying ~3/4 of total-population) and increases gap junction conductance among neurons. Their interaction spreads the orexin-elicited partial-excitation to activate SLD network globally. Besides, the activated SLD network exhibits increased probability of synchronized firings. This synchronized excitation promotes the correspondence between SLD and its downstream target to enhance SLD output. Using optogenetics and fiber-photometry, we consequently find that orexin-enhanced SLD output prolongs REM sleep episodes through consolidating brain state activation/muscle tone inhibition. After chemogenetic silencing of SLD orexin signaling, a ~17% reduction of REM sleep amounts and disruptions of REM sleep muscle atonia are observed. These findings reveal a stabilization role of orexin in REM sleep. Orexin signaling is provided by diffusely distributed fibers and involved in different brain circuits that orchestrate sleep and wakefulness states. Here, the authors show that a proportion of orexin neurons project to the sublaterodorsal tegmental nucleus and exhibit rapid eye movement (REM) sleep-related actions.
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Affiliation(s)
- Hui Feng
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Si-Yi Wen
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Qi-Cheng Qiao
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Yu-Jie Pang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Sheng-Yun Wang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Hao-Yi Li
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Jiao Cai
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Kai-Xuan Zhang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Jing Chen
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Zhi-An Hu
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Fen-Lan Luo
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Guan-Zhong Wang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China
| | - Nian Yang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China.
| | - Jun Zhang
- Department of Physiology, Third Military Medical University, 400038, Chongqing, P.R. China.
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18
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Pace M, Falappa M, Freschi A, Balzani E, Berteotti C, Lo Martire V, Kaveh F, Hovig E, Zoccoli G, Amici R, Cerri M, Urbanucci A, Tucci V. Loss of Snord116 impacts lateral hypothalamus, sleep, and food-related behaviors. JCI Insight 2020; 5:137495. [PMID: 32365348 DOI: 10.1172/jci.insight.137495] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 04/24/2020] [Indexed: 12/14/2022] Open
Abstract
Imprinted genes are highly expressed in the hypothalamus; however, whether specific imprinted genes affect hypothalamic neuromodulators and their functions is unknown. It has been suggested that Prader-Willi syndrome (PWS), a neurodevelopmental disorder caused by lack of paternal expression at chromosome 15q11-q13, is characterized by hypothalamic insufficiency. Here, we investigate the role of the paternally expressed Snord116 gene within the context of sleep and metabolic abnormalities of PWS, and we report a significant role of this imprinted gene in the function and organization of the 2 main neuromodulatory systems of the lateral hypothalamus (LH) - namely, the orexin (OX) and melanin concentrating hormone (MCH) - systems. We observed that the dynamics between neuronal discharge in the LH and the sleep-wake states of mice with paternal deletion of Snord116 (PWScrm+/p-) are compromised. This abnormal state-dependent neuronal activity is paralleled by a significant reduction in OX neurons in the LH of mutant mice. Therefore, we propose that an imbalance between OX- and MCH-expressing neurons in the LH of mutant mice reflects a series of deficits manifested in the PWS, such as dysregulation of rapid eye movement (REM) sleep, food intake, and temperature control.
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Affiliation(s)
- Marta Pace
- Genetics and Epigenetics of Behaviour Laboratory, Istituto Italiano di Tecnologia, via Morego 30, Italy
| | - Matteo Falappa
- Genetics and Epigenetics of Behaviour Laboratory, Istituto Italiano di Tecnologia, via Morego 30, Italy.,Dipartimento di Neuroscienze, Riabilitazione, Oftalmologia, Genetica e Scienze Materno-Infantili (DINOGMI), Università degli Studi di Genova, Genova, Italy
| | - Andrea Freschi
- Genetics and Epigenetics of Behaviour Laboratory, Istituto Italiano di Tecnologia, via Morego 30, Italy
| | - Edoardo Balzani
- Genetics and Epigenetics of Behaviour Laboratory, Istituto Italiano di Tecnologia, via Morego 30, Italy
| | - Chiara Berteotti
- PRISM Lab, Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Viviana Lo Martire
- PRISM Lab, Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Fatemeh Kaveh
- Department of Tumor Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Eivind Hovig
- Department of Tumor Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Centre for Bioinformatics, Department of Informatics, University of Oslo, Oslo, Norway
| | - Giovanna Zoccoli
- PRISM Lab, Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Roberto Amici
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Matteo Cerri
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Alfonso Urbanucci
- Department of Tumor Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Valter Tucci
- Genetics and Epigenetics of Behaviour Laboratory, Istituto Italiano di Tecnologia, via Morego 30, Italy
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19
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Abstract
Over the past decade, basic sleep research investigating the circuitry controlling sleep and wakefulness has been boosted by pharmacosynthetic approaches, including chemogenetic techniques using designed receptors exclusively activated by designer drugs (DREADD). DREADD offers a series of tools that selectively control neuronal activity as a way to probe causal relationship between neuronal sub-populations and the regulation of the sleep-wake cycle. Following the path opened by optogenetics, DREADD tools applied to discrete neuronal sub-populations in numerous brain areas quickly made their contribution to the discovery and the expansion of our understanding of critical brain structures involved in a wide variety of behaviors and in the control of vigilance state architecture.
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20
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Briggs C, Bowes SC, Semba K, Hirasawa M. Sleep deprivation-induced pre- and postsynaptic modulation of orexin neurons. Neuropharmacology 2018; 154:50-60. [PMID: 30586566 DOI: 10.1016/j.neuropharm.2018.12.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 12/20/2018] [Accepted: 12/21/2018] [Indexed: 10/27/2022]
Abstract
Sleep/wake states are controlled by sleep- and wake-promoting systems, and transitions between states are thought to be regulated by their reciprocal inhibition and homeostatic sleep need. Orexin neurons are known to promote wake maintenance and stabilize the sleep/wake switch. Thus, we asked whether orexin neurons are modulated by homeostatic sleep need. Rats were sleep deprived or left undisturbed to rest for 6 h, then acute brain slices were generated for patch clamp recordings. We found that sleep deprivation increased firing and reduced spike frequency adaptation in response to excitatory drive in orexin neurons. These changes were specific to D-type orexin neurons which, unlike H-type orexin neurons, lack A-type current. In D-type orexin neurons, sleep deprivation decreased afterhyperpolarizing potential, which was associated with increased gain, measured as the slope of the input-output relationship. These effects were mimicked by inhibition of SK channels. Furthermore, sleep deprivation resulted in presynaptic inhibition of excitatory inputs to both D-type and H-type orexin neurons, which preferentially affected sparse synaptic inputs while sparing high frequency synaptic activities. Taken together, our results indicate that sleep deprivation modulates the gain control and synaptic gating in orexin neurons. These pre-and postsynaptic changes would tune orexin neurons to strong wake-promoting excitatory signals, while dampening weak synaptic inputs to allow transition to sleep in the absence of such strong signals. These mechanisms are consistent with a role of orexin neurons not only as a key state stabilizer, but also as a homeostatic wake integrator in the sleep/wake switch. This article is part of the Special Issue entitled 'Hypothalamic Control of Homeostasis'.
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Affiliation(s)
- Chantalle Briggs
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, St. John's, NL, A1B 3V6, Canada; Department of Medical Neuroscience, Faculty of Medicine, Dalhousie University, 5850 College Street, Halifax, NS, B3H 4R2, Canada
| | - Sherri C Bowes
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, St. John's, NL, A1B 3V6, Canada
| | - Kazue Semba
- Department of Medical Neuroscience, Faculty of Medicine, Dalhousie University, 5850 College Street, Halifax, NS, B3H 4R2, Canada; Department of Psychiatry, Faculty of Medicine, Dalhousie University, 5909 Veterans' Memorial Lane, Halifax, NS, B3H 2E2, Canada; Department of Psychology and Neuroscience, Faculty of Science, Dalhousie University, 1355 Oxford Street, Halifax, NS, B3H 4R2, Canada
| | - Michiru Hirasawa
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, St. John's, NL, A1B 3V6, Canada.
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21
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Burdakov D. Reactive and predictive homeostasis: Roles of orexin/hypocretin neurons. Neuropharmacology 2018; 154:61-67. [PMID: 30347195 DOI: 10.1016/j.neuropharm.2018.10.024] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 10/14/2018] [Accepted: 10/16/2018] [Indexed: 11/30/2022]
Abstract
Homeostasis is the maintenance of a healthy physiological equilibrium in a changing world. Reactive (feedback, counter-regulatory) and predictive (feedforward, anticipatory) homeostatic control strategies are both important for survival. For example, in energy homeostasis, the pancreas reacts to ingested glucose by releasing insulin, whereas the brain prepares the body for ingestion through anticipatory salivation based on food-associated cues. Reactive control is largely innate, whereas predictive control is often acquired or modified through associative learning, though some important predictive control strategies are innate, e.g. avoidance of fox scent in mice that never met a fox. Traditionally, the hypothalamus has been viewed as a reactive controller, sensing deviations from homeostasis to elicit counter-regulatory responses, while "higher" areas such as the cortex have been viewed as predictive controllers. However, experimental evidence argues against such neuroanatomical segregation: for example, receptors for internal homeostatic indicators are found throughout the brain, while key interoceptive hypothalamic cells also rapidly sense external cues. Here a model is proposed where the brain-wide-projecting, non-neuroendocrine, neurons of the hypothalamus, exemplified by orexin/hypocretin neurons, function as "brain government" systems that convert integrated internal and external information into reactive and predictive autonomic, cognitive, and behavioural adaptations that ensure homeostasis. Like regions of a country without a government, individual brain regions can function normally without hypothalamic guidance, but these functions are uncoordinated, producing mismatch between supply and demand of arousal, and derailing decision-making as seen in orexin-deficient narcolepsy. This article is part of the Special Issue entitled 'Hypothalamic Control of Homeostasis'.
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Affiliation(s)
- Denis Burdakov
- Swiss Federal Institute of Technology / ETH Zürich, D-HEST, Institute for Neuroscience, Schorenstrasse 16, Schwerzenbach 8603, Switzerland.
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22
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Herring WJ, Roth T, Krystal AD, Michelson D. Orexin receptor antagonists for the treatment of insomnia and potential treatment of other neuropsychiatric indications. J Sleep Res 2018; 28:e12782. [DOI: 10.1111/jsr.12782] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 09/06/2018] [Accepted: 09/22/2018] [Indexed: 01/06/2023]
Affiliation(s)
| | - Thomas Roth
- Sleep Disorders and Research Center Henry Ford Hospital Detroit MI USA
| | - Andrew D. Krystal
- Department of Psychiatry University of California San Francisco California USA
| | - David Michelson
- Clinical ResearchMerck & Co., Inc. Kenilworth New Jersey USA
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23
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Chew YL, Tanizawa Y, Cho Y, Zhao B, Yu AJ, Ardiel EL, Rabinowitch I, Bai J, Rankin CH, Lu H, Beets I, Schafer WR. An Afferent Neuropeptide System Transmits Mechanosensory Signals Triggering Sensitization and Arousal in C. elegans. Neuron 2018; 99:1233-1246.e6. [PMID: 30146306 PMCID: PMC6162336 DOI: 10.1016/j.neuron.2018.08.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 06/22/2018] [Accepted: 08/02/2018] [Indexed: 11/05/2022]
Abstract
Sensitization is a simple form of behavioral plasticity by which an initial stimulus, often signaling danger, leads to increased responsiveness to subsequent stimuli. Cross-modal sensitization is an important feature of arousal in many organisms, yet its molecular and neural mechanisms are incompletely understood. Here we show that in C. elegans, aversive mechanical stimuli lead to both enhanced locomotor activity and sensitization of aversive chemosensory pathways. Both locomotor arousal and cross-modal sensitization depend on the release of FLP-20 neuropeptides from primary mechanosensory neurons and on their receptor FRPR-3. Surprisingly, the critical site of action of FRPR-3 for both sensory and locomotor arousal is RID, a single neuroendocrine cell specialized for the release of neuropeptides that responds to mechanical stimuli in a FLP-20-dependent manner. Thus, FLP-20 peptides function as an afferent arousal signal that conveys mechanosensory information to central neurons that modulate arousal and other behavioral states.
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Affiliation(s)
- Yee Lian Chew
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, Cambridgeshire, CB2 0QH, UK
| | - Yoshinori Tanizawa
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, Cambridgeshire, CB2 0QH, UK
| | - Yongmin Cho
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0100, USA
| | - Buyun Zhao
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, Cambridgeshire, CB2 0QH, UK
| | - Alex J Yu
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC V6T, Canada
| | - Evan L Ardiel
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC V6T, Canada
| | - Ithai Rabinowitch
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Department of Medical Neurobiology, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem 91120, Israel
| | - Jihong Bai
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Catharine H Rankin
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC V6T, Canada; Department of Psychology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Hang Lu
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0100, USA
| | - Isabel Beets
- Cell Biology Division, MRC Laboratory of Molecular Biology, Cambridge, Cambridgeshire, CB2 0QH, UK; Department of Biology, Division of Animal Physiology and Neurobiology, KU Leuven, B-3000, Leuven, Belgium
| | - William R Schafer
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge, Cambridgeshire, CB2 0QH, UK.
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Nevárez N, de Lecea L. Recent advances in understanding the roles of hypocretin/orexin in arousal, affect, and motivation. F1000Res 2018; 7. [PMID: 30254737 PMCID: PMC6127742 DOI: 10.12688/f1000research.15097.1] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/24/2018] [Indexed: 12/11/2022] Open
Abstract
The hypocretins (Hcrts) are two alternatively spliced neuropeptides (Hcrt1/Ox-A and Hcrt2/Ox-B) that are synthesized exclusively in the hypothalamus. Data collected in the 20 years since their discovery have supported the view that the Hcrts play a broad role in the control of arousal with a particularly important role in the maintenance of wakefulness and sleep-to-wake transitions. While this latter point has received an overwhelming amount of research attention, a growing literature has begun to broaden our understanding of the many diverse roles that the Hcrts play in physiology and behavior. Here, we review recent advances in the neurobiology of Hcrt in three sections. We begin by surveying findings on Hcrt function within normal sleep/wake states as well as situations of aberrant sleep (that is, narcolepsy). In the second section, we discuss research establishing a role for Hcrt in mood and affect (that is, anxiety, stress, and motivation). Finally, in the third section, we briefly discuss future directions for the field and place an emphasis on analytical modeling of Hcrt neural activity. We hope that the data discussed here provide a broad overview of recent progress in the field and make clear the diversity of roles played by these neuromodulators.
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Affiliation(s)
- Natalie Nevárez
- Department of Psychiatry & Behavioral Sciences, Stanford University, Stanford, California, USA
| | - Luis de Lecea
- Department of Psychiatry & Behavioral Sciences, Stanford University, Stanford, California, USA
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25
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Barson JR. Orexin/hypocretin and dysregulated eating: Promotion of foraging behavior. Brain Res 2018; 1731:145915. [PMID: 30125533 DOI: 10.1016/j.brainres.2018.08.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/31/2018] [Accepted: 08/15/2018] [Indexed: 12/14/2022]
Abstract
At its discovery, orexin/hypocretin (OX) was hypothesized to promote food intake. Subsequently, with the identification of the participation of OX in numerous other phenomena, including arousal and drug seeking, this neuropeptide was proposed to be involved in highly motivated behaviors. The present review develops the hypothesis that the primary evolutionary function of OX is to promote foraging behavior, seeking for food under conditions of limited availability. Thus, it will first describe published literature on OX and homeostatic food intake, which shows that OX neurons are activated by conditions of food deprivation and in turn stimulate food intake. Next, it will present literature on excessive and binge-like food intake, which demonstrates that OX stimulates both intake and willingness to work for palatable food. Importantly, studies show that binge-like eating can be inhibited by OX antagonists at doses far lower than those required to suppress homeostatic intake (3 mg/kg vs. 30 mg/kg), suggesting that an OX-based pharmacotherapy, at the right dose, could specifically control dysregulated eating. Finally, the review will discuss the role of OX in foraging behavior, citing literature which shows that OX neurons, which are activated during the anticipation of food reward, can promote a number of phenomena involved in successful foraging, including food-anticipatory locomotor behavior, olfactory sensitivity, visual attention, spatial memory, and mastication. Thus, OX may promote homeostatic eating, as well as binge eating of palatable food, due to its ability to stimulate and coordinate the activities involved in foraging behavior.
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Affiliation(s)
- Jessica R Barson
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA 19129, USA.
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26
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Moorman DE. The hypocretin/orexin system as a target for excessive motivation in alcohol use disorders. Psychopharmacology (Berl) 2018; 235:1663-1680. [PMID: 29508004 PMCID: PMC5949267 DOI: 10.1007/s00213-018-4871-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 02/20/2018] [Indexed: 12/17/2022]
Abstract
The hypocretin/orexin (ORX) system has been repeatedly demonstrated to regulate motivation for drugs of abuse, including alcohol. In particular, ORX seems to be critically involved in highly motivated behaviors, as is observed in high-seeking individuals in a population, in the seeking of highly palatable substances, and in models of dependence. It seems logical that this system could be considered as a potential target for treatment for addiction, particularly alcohol addiction, as ORX pharmacological manipulations significantly reduce drinking. However, the ORX system also plays a role in a wide range of other behaviors, emotions, and physiological functions and is disrupted in a number of non-dependence-associated disorders. It is therefore important to consider how the ORX system might be optimally targeted for potential treatment for alcohol use disorders either in combination with or separate from its role in other functions or diseases. This review will focus on the role of ORX in alcohol-associated behaviors and whether and how this system could be targeted to treat alcohol use disorders while avoiding impacts on other ORX-relevant functions. A brief overview of the ORX system will be followed by a discussion of some of the factors that makes it particularly intriguing as a target for alcohol addiction treatment, a consideration of some potential challenges associated with targeting this system and, finally, some future directions to optimize new treatments.
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Affiliation(s)
- David E Moorman
- Department of Psychological and Brain Sciences, Neuroscience and Behavior Graduate Program, University of Massachusetts Amherst, 528 Tobin Hall, 135 Hicks Way, Amherst, MA, 01003, USA.
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27
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Ma S, Hangya B, Leonard CS, Wisden W, Gundlach AL. Dual-transmitter systems regulating arousal, attention, learning and memory. Neurosci Biobehav Rev 2018; 85:21-33. [PMID: 28757457 PMCID: PMC5747977 DOI: 10.1016/j.neubiorev.2017.07.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 07/16/2017] [Indexed: 01/12/2023]
Abstract
An array of neuromodulators, including monoamines and neuropeptides, regulate most behavioural and physiological traits. In the past decade, dramatic progress has been made in mapping neuromodulatory circuits, in analysing circuit dynamics, and interrogating circuit function using pharmacogenetic, optogenetic and imaging methods This review will focus on several distinct neural networks (acetylcholine/GABA/glutamate; histamine/GABA; orexin/glutamate; and relaxin-3/GABA) that originate from neural hubs that regulate wakefulness and related attentional and cognitive processes, and highlight approaches that have identified dual transmitter roles in these behavioural functions. Modulation of these different neural networks might be effective treatments of diseases related to arousal/sleep dysfunction and of cognitive dysfunction in psychiatric and neurodegenerative disorders.
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Affiliation(s)
- Sherie Ma
- The Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia; Florey Department of Neuroscience and Mental Health, The University of Melbourne, Victoria, Australia.
| | - Balázs Hangya
- 'Lendület' Laboratory of Systems Neuroscience, Department of Cellular and Network Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | | | - William Wisden
- Department of Life Sciences, Imperial College London, London, UK
| | - Andrew L Gundlach
- The Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia; Florey Department of Neuroscience and Mental Health, The University of Melbourne, Victoria, Australia; Department of Anatomy and Neuroscience, The University of Melbourne, Victoria, Australia.
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28
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Yu X, Franks NP, Wisden W. Sleep and Sedative States Induced by Targeting the Histamine and Noradrenergic Systems. Front Neural Circuits 2018; 12:4. [PMID: 29434539 PMCID: PMC5790777 DOI: 10.3389/fncir.2018.00004] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 01/11/2018] [Indexed: 01/07/2023] Open
Abstract
Sedatives target just a handful of receptors and ion channels. But we have no satisfying explanation for how activating these receptors produces sedation. In particular, do sedatives act at restricted brain locations and circuitries or more widely? Two prominent sedative drugs in clinical use are zolpidem, a GABAA receptor positive allosteric modulator, and dexmedetomidine (DEX), a selective α2 adrenergic receptor agonist. By targeting hypothalamic neuromodulatory systems both drugs induce a sleep-like state, but in different ways: zolpidem primarily reduces the latency to NREM sleep, and is a controlled substance taken by many people to help them sleep; DEX produces prominent slow wave activity in the electroencephalogram (EEG) resembling stage 2 NREM sleep, but with complications of hypothermia and lowered blood pressure—it is used for long term sedation in hospital intensive care units—under DEX-induced sedation patients are arousable and responsive, and this drug reduces the risk of delirium. DEX, and another α2 adrenergic agonist xylazine, are also widely used in veterinary clinics to sedate animals. Here we review how these two different classes of sedatives, zolpidem and dexmedetomideine, can selectively interact with some nodal points of the circuitry that promote wakefulness allowing the transition to NREM sleep. Zolpidem enhances GABAergic transmission onto histamine neurons in the hypothalamic tuberomammillary nucleus (TMN) to hasten the transition to NREM sleep, and DEX interacts with neurons in the preoptic hypothalamic area that induce sleep and body cooling. This knowledge may aid the design of more precise acting sedatives, and at the same time, reveal more about the natural sleep-wake circuitry.
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Affiliation(s)
- Xiao Yu
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Nicholas P Franks
- Department of Life Sciences, Imperial College London, London, United Kingdom.,Centre for Neurotechnology, Imperial College London, London, United Kingdom.,UK Dementia Research Institute, Imperial College London, London, United Kingdom
| | - William Wisden
- Department of Life Sciences, Imperial College London, London, United Kingdom.,Centre for Neurotechnology, Imperial College London, London, United Kingdom.,UK Dementia Research Institute, Imperial College London, London, United Kingdom
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29
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Anderson RI, Moorman DE, Becker HC. Contribution of Dynorphin and Orexin Neuropeptide Systems to the Motivational Effects of Alcohol. Handb Exp Pharmacol 2018. [PMID: 29526023 DOI: 10.1007/164_2018_100] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Understanding the neural systems that drive alcohol motivation and are disrupted in alcohol use disorders is of critical importance in developing novel treatments. The dynorphin and orexin/hypocretin neuropeptide systems are particularly relevant with respect to alcohol use and misuse. Both systems are strongly associated with alcohol-seeking behaviors, particularly in cases of high levels of alcohol use as seen in dependence. Furthermore, both systems also play a role in stress and anxiety, indicating that disruption of these systems may underlie long-term homeostatic dysregulation seen in alcohol use disorders. These systems are also closely interrelated with one another - dynorphin/kappa opioid receptors and orexin/hypocretin receptors are found in similar regions and hypocretin/orexin neurons also express dynorphin - suggesting that these two systems may work together in the regulation of alcohol seeking and may be mutually disrupted in alcohol use disorders. This chapter reviews studies demonstrating a role for each of these systems in motivated behavior, with a focus on their roles in regulating alcohol-seeking and self-administration behaviors. Consideration is also given to evidence indicating that these neuropeptide systems may be viable targets for the development of potential treatments for alcohol use disorders.
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Affiliation(s)
- Rachel I Anderson
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA.,Science and Technology Policy Fellowships, American Association for the Advancement of Science, Washington, DC, USA
| | - David E Moorman
- Department of Psychological and Brain Sciences, Neuroscience and Behavior Graduate Program, University of Massachusetts Amherst, Amherst, MA, USA
| | - Howard C Becker
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA. .,Charleston Alcohol Research Center, Medical University of South Carolina, Charleston, SC, USA. .,Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA. .,Department of Veterans Affairs, Ralph H. Johnson VA Medical Center, Charleston, SC, USA.
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30
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Yakovleva OV, Lyashenko EA, Poluektov MG. Dysfunction of the orexin system in Parkinson's disease. Zh Nevrol Psikhiatr Im S S Korsakova 2018; 118:82-89. [DOI: 10.17116/jnevro201811806282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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