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Wong TS, Li G, Li S, Gao W, Chen G, Gan S, Zhang M, Li H, Wu S, Du Y. G protein-coupled receptors in neurodegenerative diseases and psychiatric disorders. Signal Transduct Target Ther 2023; 8:177. [PMID: 37137892 PMCID: PMC10154768 DOI: 10.1038/s41392-023-01427-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 02/17/2023] [Accepted: 03/30/2023] [Indexed: 05/05/2023] Open
Abstract
Neuropsychiatric disorders are multifactorial disorders with diverse aetiological factors. Identifying treatment targets is challenging because the diseases are resulting from heterogeneous biological, genetic, and environmental factors. Nevertheless, the increasing understanding of G protein-coupled receptor (GPCR) opens a new possibility in drug discovery. Harnessing our knowledge of molecular mechanisms and structural information of GPCRs will be advantageous for developing effective drugs. This review provides an overview of the role of GPCRs in various neurodegenerative and psychiatric diseases. Besides, we highlight the emerging opportunities of novel GPCR targets and address recent progress in GPCR drug development.
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Affiliation(s)
- Thian-Sze Wong
- Kobilka Institute of Innovative Drug Discovery, Shenzhen Key Laboratory of Steroid Drug Discovery and Development, School of Medicine, The Chinese University of Hong Kong, 518172, Shenzhen, Guangdong, China
- School of Medicine, Tsinghua University, 100084, Beijing, China
| | - Guangzhi Li
- Institute of Urology, The Affiliated Luohu Hospital of Shenzhen University, Shenzhen University, 518000, Shenzhen, Guangdong, China
| | - Shiliang Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 200237, Shanghai, China
- Innovation Center for AI and Drug Discovery, East China Normal University, 200062, Shanghai, China
| | - Wei Gao
- Kobilka Institute of Innovative Drug Discovery, Shenzhen Key Laboratory of Steroid Drug Discovery and Development, School of Medicine, The Chinese University of Hong Kong, 518172, Shenzhen, Guangdong, China
- Innovation Center for AI and Drug Discovery, East China Normal University, 200062, Shanghai, China
| | - Geng Chen
- Kobilka Institute of Innovative Drug Discovery, Shenzhen Key Laboratory of Steroid Drug Discovery and Development, School of Medicine, The Chinese University of Hong Kong, 518172, Shenzhen, Guangdong, China
| | - Shiyi Gan
- Kobilka Institute of Innovative Drug Discovery, Shenzhen Key Laboratory of Steroid Drug Discovery and Development, School of Medicine, The Chinese University of Hong Kong, 518172, Shenzhen, Guangdong, China
| | - Manzhan Zhang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 200237, Shanghai, China
- Innovation Center for AI and Drug Discovery, East China Normal University, 200062, Shanghai, China
| | - Honglin Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 200237, Shanghai, China.
- Innovation Center for AI and Drug Discovery, East China Normal University, 200062, Shanghai, China.
| | - Song Wu
- Institute of Urology, The Affiliated Luohu Hospital of Shenzhen University, Shenzhen University, 518000, Shenzhen, Guangdong, China.
- Department of Urology, South China Hospital, Health Science Center, Shenzhen University, 518116, Shenzhen, Guangdong, China.
| | - Yang Du
- Kobilka Institute of Innovative Drug Discovery, Shenzhen Key Laboratory of Steroid Drug Discovery and Development, School of Medicine, The Chinese University of Hong Kong, 518172, Shenzhen, Guangdong, China.
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2
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Dickson E, Dwijesha AS, Andersson N, Lundh S, Björkqvist M, Petersén Å, Soylu-Kucharz R. Microarray profiling of hypothalamic gene expression changes in Huntington’s disease mouse models. Front Neurosci 2022; 16:1027269. [DOI: 10.3389/fnins.2022.1027269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022] Open
Abstract
Structural changes and neuropathology in the hypothalamus have been suggested to contribute to the non-motor manifestations of Huntington’s disease (HD), a neurodegenerative disorder caused by an expanded cytosine-adenine-guanine (CAG) repeat in the huntingtin (HTT) gene. In this study, we investigated whether hypothalamic HTT expression causes transcriptional changes. Hypothalamic RNA was isolated from two different HD mouse models and their littermate controls; BACHD mice with ubiquitous expression of full-length mutant HTT (mHTT) and wild-type mice with targeted hypothalamic overexpression of either wild-type HTT (wtHTT) or mHTT fragments. The mHTT and wtHTT groups showed the highest number of differentially expressed genes compared to the BACHD mouse model. Gene Set Enrichment Analysis (GSEA) with leading-edge analysis showed that suppressed sterol- and cholesterol metabolism were shared between hypothalamic wtHTT and mHTT overexpression. Most distinctive for mHTT overexpression was the suppression of neuroendocrine networks, in which qRT-PCR validation confirmed significant downregulation of neuropeptides with roles in feeding behavior; hypocretin neuropeptide precursor (Hcrt), tachykinin receptor 3 (Tacr3), cocaine and amphetamine-regulated transcript (Cart) and catecholamine-related biological processes; dopa decarboxylase (Ddc), histidine decarboxylase (Hdc), tyrosine hydroxylase (Th), and vasoactive intestinal peptide (Vip). In BACHD mice, few hypothalamic genes were differentially expressed compared to age-matched WT controls. However, GSEA indicated an enrichment of inflammatory- and gonadotropin-related processes at 10 months. In conclusion, we show that both wtHTT and mHTT overexpression change hypothalamic transcriptome profile, specifically mHTT, altering neuroendocrine circuits. In contrast, the ubiquitous expression of full-length mHTT in the BACHD hypothalamus moderately affects the transcriptomic profile.
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3
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Pizza F, Barateau L, Dauvilliers Y, Plazzi G. The orexin story, sleep and sleep disturbances. J Sleep Res 2022; 31:e13665. [PMID: 35698789 DOI: 10.1111/jsr.13665] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 05/16/2022] [Accepted: 05/17/2022] [Indexed: 01/02/2023]
Abstract
The orexins, also known as hypocretins, are two neuropeptides (orexin A and B or hypocretin 1 and 2) produced by a few thousand neurons located in the lateral hypothalamus that were independently discovered by two research groups in 1998. Those two peptides bind two receptors (orexin/hypocretin receptor 1 and receptor 2) that are widely distributed in the brain and involved in the central physiological regulation of sleep and wakefulness, orexin receptor 2 having the major role in the maintenance of arousal. They are also implicated in a multiplicity of other functions, such as reward seeking, energy balance, autonomic regulation and emotional behaviours. The destruction of orexin neurons is responsible for the sleep disorder narcolepsy with cataplexy (type 1) in humans, and a defect of orexin signalling also causes a narcoleptic phenotype in several animal species. Orexin discovery is unprecedented in the history of sleep research, and pharmacological manipulations of orexin may have multiple therapeutic applications. Several orexin receptor antagonists were recently developed as new drugs for insomnia, and orexin agonists may be the next-generation drugs for narcolepsy. Given the broad range of functions of the orexin system, these drugs might also be beneficial for treating various conditions other than sleep disorders in the near future.
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Affiliation(s)
- Fabio Pizza
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.,IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Lucie Barateau
- Sleep-Wake Disorders Unit, Department of Neurology, Gui-de-Chauliac Hospital, CHU Montpellier, Montpellier, France.,National Reference Centre for Orphan Diseases, Narcolepsy, Idiopathic Hypersomnia, and Kleine-Levin Syndrome, Montpellier, France.,Institute for Neurosciences of Montpellier, University of Montpellier, INSERM, Montpellier, France
| | - Yves Dauvilliers
- Sleep-Wake Disorders Unit, Department of Neurology, Gui-de-Chauliac Hospital, CHU Montpellier, Montpellier, France.,National Reference Centre for Orphan Diseases, Narcolepsy, Idiopathic Hypersomnia, and Kleine-Levin Syndrome, Montpellier, France.,Institute for Neurosciences of Montpellier, University of Montpellier, INSERM, Montpellier, France
| | - Giuseppe Plazzi
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy.,Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
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4
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Henningsen JB, Soylu-Kucharz R, Björkqvist M, Petersén Å. Effects of excitotoxicity in the hypothalamus in transgenic mouse models of Huntington disease. Heliyon 2021; 7:e07808. [PMID: 34458633 PMCID: PMC8379469 DOI: 10.1016/j.heliyon.2021.e07808] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 04/21/2021] [Accepted: 08/12/2021] [Indexed: 11/18/2022] Open
Abstract
Huntington disease (HD) is a fatal neurodegenerative movement disorder caused by an expanded CAG repeat in the huntingtin gene (HTT). The mutant huntingtin protein is ubiquitously expressed, but only certain brain regions are affected. The hypothalamus has emerged as an important area of pathology with selective loss of neurons expressing the neuropeptides orexin (hypocretin), oxytocin and vasopressin in human postmortem HD tissue. Hypothalamic changes in HD may have implications for early disease manifestations affecting the regulation of sleep, emotions and metabolism. The underlying mechanisms of selective vulnerability of certain neurons in HD are not fully understood, but excitotoxicity has been proposed to play a role. Further understanding of mechanisms rendering neurons sensitive to mutant huntingtin may reveal novel targets for therapeutic interventions. In the present study, we wanted to examine whether transgenic HD mice display altered sensitivity to excitotoxicity in the hypothalamus. We first assessed effects of hypothalamic injections of the excitotoxin quinolinic acid (QA) into wild-type (WT) mice. We show that neuronal populations expressing melanin-concentrating hormone (MCH) and cocaine and amphetamine-regulated transcript (CART) display a dose-dependent sensitivity to QA. In contrast, neuronal populations expressing orexin, oxytocin, vasopressin as well as tyrosine hydroxylase in the A13 area are resistant to QA-induced toxicity. We demonstrate that the R6/2 transgenic mouse model expressing a short fragment of mutant HTT displays hypothalamic neuropathology with discrete loss of the neuronal populations expressing orexin, MCH, CART, and orexin at 12 weeks of age. The BACHD mouse model expressing full-length mutant HTT does not display any hypothalamic neuropathology at 2 months of age. There was no effect of hypothalamic injections of QA on the neuronal populations expressing orexin, MCH, CART or oxytocin in neither HD mouse model. In conclusion, we find no support for a role of excitotoxicity in the loss of hypothalamic neuronal populations in HD.
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Affiliation(s)
- Jo B. Henningsen
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, 22184, Lund, Sweden
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, 2200, Copenhagen, Denmark
- Corresponding author.
| | - Rana Soylu-Kucharz
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, 22184, Lund, Sweden
- Brain Disease Biomarker Unit, Department of Experimental Medical Science, Lund University, 22184, Lund, Sweden
| | - Maria Björkqvist
- Brain Disease Biomarker Unit, Department of Experimental Medical Science, Lund University, 22184, Lund, Sweden
| | - Åsa Petersén
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, 22184, Lund, Sweden
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5
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Cheong RY, Baldo B, Sajjad MU, Kirik D, Petersén Å. Effects of mutant huntingtin inactivation on Huntington disease-related behaviours in the BACHD mouse model. Neuropathol Appl Neurobiol 2021; 47:564-578. [PMID: 33330988 PMCID: PMC8247873 DOI: 10.1111/nan.12682] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 10/27/2020] [Accepted: 12/14/2020] [Indexed: 01/02/2023]
Abstract
AIMS Huntington disease (HD) is a fatal neurodegenerative disorder with no disease-modifying treatments approved so far. Ongoing clinical trials are attempting to reduce huntingtin (HTT) expression in the central nervous system (CNS) using different strategies. Yet, the distribution and timing of HTT-lowering therapies required for a beneficial clinical effect is less clear. Here, we investigated whether HD-related behaviours could be prevented by inactivating mutant HTT at different disease stages and to varying degrees in an experimental model. METHODS We generated mutant BACHD mice with either a widespread or circuit-specific inactivation of mutant HTT by using Cre recombinase (Cre) under the nestin promoter or the adenosine A2A receptor promoter respectively. We also simulated a clinical gene therapy scenario with allele-specific HTT targeting by injections of recombinant adeno-associated viral (rAAV) vectors expressing Cre into the striatum of adult BACHD mice. All mice were assessed using behavioural tests to investigate motor, metabolic and psychiatric outcome measures at 4-6 months of age. RESULTS While motor deficits, body weight changes, anxiety and depressive-like behaviours are present in BACHD mice, early widespread CNS inactivation during development significantly improves rotarod performance, body weight changes and depressive-like behaviour. However, conditional circuit-wide mutant HTT deletion from the indirect striatal pathway during development and focal striatal-specific deletion in adulthood failed to rescue any of the HD-related behaviours. CONCLUSIONS Our results indicate that widespread targeting and the timing of interventions aimed at reducing mutant HTT are important factors to consider when developing disease-modifying therapies for HD.
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Affiliation(s)
- Rachel Y. Cheong
- Translational Neuroendocrine Research UnitDepartment of Experimental Medical ScienceLund UniversityLundSweden
| | - Barbara Baldo
- Translational Neuroendocrine Research UnitDepartment of Experimental Medical ScienceLund UniversityLundSweden
- Present address:
Evotec SEHD Research and Translational SciencesHamburgGermany
| | - Muhammad U. Sajjad
- Translational Neuroendocrine Research UnitDepartment of Experimental Medical ScienceLund UniversityLundSweden
| | - Deniz Kirik
- Brain Repair and Imaging in Neural Systems UnitDepartment of Experimental Medical ScienceLund UniversityLundSweden
| | - Åsa Petersén
- Translational Neuroendocrine Research UnitDepartment of Experimental Medical ScienceLund UniversityLundSweden
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6
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Schneider WT, Vas S, Nicol AU, Morton AJ. Abnormally abrupt transitions from sleep-to-wake in Huntington's disease sheep (Ovis aries) are revealed by automated analysis of sleep/wake transition dynamics. PLoS One 2021; 16:e0251767. [PMID: 33984047 PMCID: PMC8118338 DOI: 10.1371/journal.pone.0251767] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 05/02/2021] [Indexed: 11/28/2022] Open
Abstract
Sleep disturbance is a common and disruptive symptom of neurodegenerative diseases such as Alzheimer’s and Huntington’s disease (HD). In HD patients, sleep fragmentation appears at an early stage of disease, although features of the earliest sleep abnormalities in presymptomatic HD are not fully established. Here we used novel automated analysis of quantitative electroencephalography to study transitions between wake and non-rapid eye movement sleep in a sheep model of presymptomatic HD. We found that while the number of transitions between sleep and wake were similar in normal and HD sheep, the dynamics of transitions from sleep-to-wake differed markedly between genotypes. Rather than the gradual changes in EEG power that occurs during transitioning from sleep-to-wake in normal sheep, transition into wake was abrupt in HD sheep. Furthermore, transitions to wake in normal sheep were preceded by a significant reduction in slow wave power, whereas in HD sheep this prior reduction in slow wave power was far less pronounced. This suggests an impaired ability to prepare for waking in HD sheep. The abruptness of awakenings may also have potential to disrupt sleep-dependent processes if they are interrupted in an untimely and disjointed manner. We propose that not only could these abnormal dynamics of sleep transitions be useful as an early biomarker of HD, but also that our novel methodology would be useful for studying transition dynamics in other sleep disorders.
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Affiliation(s)
- William T. Schneider
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Szilvia Vas
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Alister U. Nicol
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - A. Jennifer Morton
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
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7
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Voysey Z, Fazal SV, Lazar AS, Barker RA. The sleep and circadian problems of Huntington's disease: when, why and their importance. J Neurol 2020; 268:2275-2283. [PMID: 33355880 PMCID: PMC8179890 DOI: 10.1007/s00415-020-10334-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/15/2020] [Accepted: 11/19/2020] [Indexed: 11/30/2022]
Abstract
Introduction Mounting evidence supports the existence of an important feedforward cycle between sleep and neurodegeneration, wherein neurodegenerative diseases cause sleep and circadian abnormalities, which in turn exacerbate and accelerate neurodegeneration. If so, sleep therapies bear important potential to slow progression in these diseases. Findings This cycle is challenging to study, as its bidirectional nature renders cause difficult to disentangle from effect. Likewise, well-controlled intervention studies are often impractical in the setting of established neurodegenerative disease. It is this that makes understanding sleep and circadian abnormalities in Huntington’s disease (HD) important: as a monogenic fully penetrant neurodegenerative condition presenting in midlife, it provides a rare opportunity to study sleep and circadian abnormalities longitudinally, prior to and throughout disease manifestation, and in the absence of confounds rendered by age and comorbidities. It also provides potential to trial sleep therapies at a preclinical or early disease stage. Moreover, its monogenic nature facilitates the development of transgenic animal models through which to run parallel pre-clinical studies. HD, therefore, provides a key model condition through which to gain new insights into the sleep-neurodegeneration interface. Conclusions Here, we begin by summarising contemporary knowledge of sleep abnormalities in HD, and consider how well these parallel those of Alzheimer’s and Parkinson’s as more common neurodegenerative conditions. We then discuss what is currently known of the sleep-neurodegeneration cyclical relationship in HD. We conclude by outlining key directions of current and future investigation by which to advance the sleep-neurodegeneration field via studies in HD.
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Affiliation(s)
- Z Voysey
- Department of Clinical Neurosciences, John Van Geest Centre for Brain Repair, University of Cambridge, Cambridge, UK.
| | - S V Fazal
- Department of Clinical Neurosciences, John Van Geest Centre for Brain Repair, University of Cambridge, Cambridge, UK
| | - A S Lazar
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, UK
| | - R A Barker
- Department of Clinical Neurosciences, John Van Geest Centre for Brain Repair, WT-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
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Cheong RY, Gabery S, Petersén Å. The Role of Hypothalamic Pathology for Non-Motor Features of Huntington's Disease. J Huntingtons Dis 2020; 8:375-391. [PMID: 31594240 PMCID: PMC6839491 DOI: 10.3233/jhd-190372] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Huntington’s disease (HD) is a fatal genetic neurodegenerative disorder. It has mainly been considered a movement disorder with cognitive symptoms and these features have been associated with pathology of the striatum and cerebral cortex. Importantly, individuals with the mutant huntingtin gene suffer from a spectrum of non-motor features often decades before the motor disorder manifests. These symptoms and signs include a range of psychiatric symptoms, sleep problems and metabolic changes with weight loss particularly in later stages. A higher body mass index at diagnosis is associated with slower disease progression. The common psychiatric symptom of apathy progresses with the disease. The fact that non-motor features are present early in the disease and that they show an association to disease progression suggest that unravelling the underlying neurobiological mechanisms may uncover novel targets for early disease intervention and better symptomatic treatment. The hypothalamus and the limbic system are important brain regions that regulate emotion, social cognition, sleep and metabolism. A number of studies using neuroimaging, postmortem human tissue and genetic manipulation in animal models of the disease has collectively shown that the hypothalamus and the limbic system are affected in HD. These findings include the loss of neuropeptide-expressing neurons such as orexin (hypocretin), oxytocin, vasopressin, somatostatin and VIP, and increased levels of SIRT1 in distinct nuclei of the hypothalamus. This review provides a summary of the results obtained so far and highlights the potential importance of these changes for the understanding of non-motor features in HD.
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Affiliation(s)
- Rachel Y Cheong
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Sanaz Gabery
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Åsa Petersén
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
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9
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Diniz GB, Bittencourt JC. The Melanin-Concentrating Hormone (MCH) System: A Tale of Two Peptides. Front Neurosci 2019; 13:1280. [PMID: 31849590 PMCID: PMC6901935 DOI: 10.3389/fnins.2019.01280] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 11/11/2019] [Indexed: 12/19/2022] Open
Abstract
The melanin-concentrating hormone (MCH) system is a robust integrator of exogenous and endogenous information, modulating arousal and energy balance in mammals. Its predominant function in teleosts, however, is to concentrate melanin in the scales, contributing to the adaptive color change observed in several teleost species. These contrasting functions resulted from a gene duplication that occurred after the teleost divergence, which resulted in the generation of two MCH-coding genes in this clade, which acquired distinctive sequences, distribution, and functions, examined in detail here. We also describe the distribution of MCH immunoreactivity and gene expression in a large number of species, in an attempt to identify its core elements. While initially originated as a periventricular peptide, with an intimate relationship with the third ventricle, multiple events of lateral migration occurred during evolution, making the ventrolateral and dorsolateral hypothalamus the predominant sites of MCH in teleosts and mammals, respectively. Substantial differences between species can be identified, likely reflecting differences in habitat and behavior. This observation aligns well with the idea that MCH is a major integrator of internal and external information, ensuring an appropriate response to ensure the organism’s homeostasis. New studies on the MCH system in species that have not yet been investigated will help us understand more precisely how these habitat changes are connected to the hypothalamic neurochemical circuits, paving the way to new intervention strategies that may be used with pharmacological purposes.
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Affiliation(s)
- Giovanne B Diniz
- Departamento de Anatomia, Instituto de Ciências Biomedicas, Universidade de São Paulo, São Paulo, Brazil.,Department of Neurosurgery, Yale School of Medicine, New Haven, CT, United States
| | - Jackson C Bittencourt
- Departamento de Anatomia, Instituto de Ciências Biomedicas, Universidade de São Paulo, São Paulo, Brazil.,Nucleo de Neurociencias e Comportamento, Instituto de Psicologia, Universidade de São Paulo, São Paulo, Brazil
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10
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Silajdžić E, Björkqvist M. A Critical Evaluation of Wet Biomarkers for Huntington's Disease: Current Status and Ways Forward. J Huntingtons Dis 2019; 7:109-135. [PMID: 29614689 PMCID: PMC6004896 DOI: 10.3233/jhd-170273] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
There is an unmet clinical need for objective biomarkers to monitor disease progression and treatment response in Huntington's disease (HD). The aim of this review is, therefore, to provide practical advice for biomarker discovery and to summarise studies on biofluid markers for HD. A PubMed search was performed to review literature with regard to candidate saliva, urine, blood and cerebrospinal fluid biomarkers for HD. Information has been organised into tables to allow a pragmatic approach to the discussion of the evidence and generation of practical recommendations for future studies. Many of the markers published converge on metabolic and inflammatory pathways, although changes in other analytes representing antioxidant and growth factor pathways have also been found. The most promising markers reflect neuronal and glial degeneration, particularly neurofilament light chain. International collaboration to standardise assays and study protocols, as well as to recruit sufficiently large cohorts, will facilitate future biomarker discovery and development.
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Affiliation(s)
- Edina Silajdžić
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Maria Björkqvist
- Department of Experimental Medical Science, Brain Disease Biomarker Unit, Wallenberg Neuroscience Center, Lund University, Lund, Sweden
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11
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Zhang Y, Ren R, Yang L, Zhou J, Li Y, Shi J, Lu L, Sanford LD, Tang X. Sleep in Huntington's disease: a systematic review and meta-analysis of polysomongraphic findings. Sleep 2019; 42:zsz154. [PMID: 31328779 PMCID: PMC6783889 DOI: 10.1093/sleep/zsz154] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 04/21/2019] [Indexed: 02/05/2023] Open
Abstract
STUDY OBJECTIVES Disturbed overnight sleep is a prominent feature of advanced stage Huntington's disease (HD). Several polysomnography (PSG) studies have reported significant changes of sleep in HD patients, but the findings are not unequivocal. To date, no meta-analysis has investigated the PSG changes in HD patients. The present study meta-analyzed results from studies examining the PSG changes in HD patients compared with controls. METHODS A literature search performed in MEDLINE, EMBASE, All EBM databases, PsycINFO, and CINAHL databases identified seven studies involving 152 HD patients and 144 controls which were included in our meta-analysis. RESULTS Pooled results indicated decreased sleep efficiency, percentage of slow wave sleep and rapid eye movement sleep, and increased percentage of N1 sleep, wake time after sleep onset, and rapid eye movement sleep latency in HD patients compared with controls. We found high heterogeneity in the effect sizes and no indication of systematic publication biases across studies. Meta-regression analyses showed that some of the heterogeneity was explained by age, body mass index (BMI), CAG repeat length, and disease severity of HD patients. CONCLUSIONS Our study showed that polysomnographic abnormalities are present in HD. Our findings also underscore the need for a comprehensive PSG assessment of sleep changes in patients with HD. Furthermore, the effects of age, BMI and CAG repeat length on sleep changes should be carefully considered and closely monitored in the management of HD.
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Affiliation(s)
- Ye Zhang
- Sleep Medicine Center, Department of Respiratory and Critical Care Medicine, Mental Health Center, Translational Neuroscience Center, and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Rong Ren
- Sleep Medicine Center, Department of Respiratory and Critical Care Medicine, Mental Health Center, Translational Neuroscience Center, and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Linghui Yang
- Sleep Medicine Center, Department of Respiratory and Critical Care Medicine, Mental Health Center, Translational Neuroscience Center, and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Junying Zhou
- Sleep Medicine Center, Department of Respiratory and Critical Care Medicine, Mental Health Center, Translational Neuroscience Center, and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Yun Li
- Sleep Medicine Center, Shantou University Medical College, Shantou, China
| | - Jie Shi
- National Institute on Drug Dependence, Peking University Sixth Hospital, Peking University, Beijing, China
| | - Lin Lu
- National Institute on Drug Dependence, Peking University Sixth Hospital, Peking University, Beijing, China
| | - Larry D Sanford
- Sleep Research Laboratory, Department of Pathology and Anatomy, Eastern Virginia Medical School, Norfolk, VA
| | - Xiangdong Tang
- Sleep Medicine Center, Department of Respiratory and Critical Care Medicine, Mental Health Center, Translational Neuroscience Center, and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
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12
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Ma L, Herren AW, Espinal G, Randol J, McLaughlin B, Martinez-Cerdeño V, Pessah IN, Hagerman RJ, Hagerman PJ. Composition of the Intranuclear Inclusions of Fragile X-associated Tremor/Ataxia Syndrome. Acta Neuropathol Commun 2019; 7:143. [PMID: 31481131 PMCID: PMC6720097 DOI: 10.1186/s40478-019-0796-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 08/24/2019] [Indexed: 12/11/2022] Open
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder associated with a premutation repeat expansion (55-200 CGG repeats) in the 5' noncoding region of the FMR1 gene. Solitary intranuclear inclusions within FXTAS neurons and astrocytes constitute a hallmark of the disorder, yet our understanding of how and why these bodies form is limited. Here, we have discovered that FXTAS inclusions emit a distinct autofluorescence spectrum, which forms the basis of a novel, unbiased method for isolating FXTAS inclusions by preparative fluorescence-activated cell sorting (FACS). Using a combination of autofluorescence-based FACS and liquid chromatography/tandem mass spectrometry (LC-MS/MS)-based proteomics, we have identified more than two hundred proteins that are enriched within the inclusions relative to FXTAS whole nuclei. Whereas no single protein species dominates inclusion composition, highly enriched levels of conjugated small ubiquitin-related modifier 2 (SUMO 2) protein and p62/sequestosome-1 (p62/SQSTM1) protein were found within the inclusions. Many additional proteins involved with RNA binding, protein turnover, and DNA damage repair were enriched within inclusions relative to total nuclear protein. The current analysis has also allowed the first direct detection, through peptide sequencing, of endogenous FMRpolyG peptide, the product of repeat-associated non-ATG (RAN) translation of the FMR1 mRNA. However, this peptide was found only at extremely low levels and not within whole FXTAS nuclear preparations, raising the question whether endogenous RAN products exist at quantities sufficient to contribute to FXTAS pathogenesis. The abundance of the inclusion-associated ubiquitin- and SUMO-based modifiers supports a model for inclusion formation as the result of increased protein loads and elevated oxidative stress leading to maladaptive autophagy. These results highlight the need to further investigate FXTAS pathogenesis in the context of endogenous systems.
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Affiliation(s)
- Lisa Ma
- Department of Biochemistry and Molecular Medicine, University of California Davis, School of Medicine, One Shields Ave, Davis, CA, USA
| | - Anthony W Herren
- Genome Center, University of California Davis, Davis, California, USA
| | - Glenda Espinal
- Department of Biochemistry and Molecular Medicine, University of California Davis, School of Medicine, One Shields Ave, Davis, CA, USA
| | - Jamie Randol
- Department of Biochemistry and Molecular Medicine, University of California Davis, School of Medicine, One Shields Ave, Davis, CA, USA
| | - Bridget McLaughlin
- Department of Pathology and Laboratory Medicine, University of California Davis, School of Medicine, Sacramento, California, USA
| | - Veronica Martinez-Cerdeño
- Department of Pathology and Laboratory Medicine, University of California Davis, School of Medicine, Sacramento, California, USA
- Institute for Pediatric Regenerative Medicine, Shriners Hospital of Northern California, University of California Davis, School of Medicine, Sacramento, California, USA
- MIND Institute, University of California Davis Health, Sacramento, California, USA
| | - Isaac N Pessah
- MIND Institute, University of California Davis Health, Sacramento, California, USA
- Department of Molecular Biosciences, University of California Davis, School of Veterinary Medicine, Davis, California, USA
| | - Randi J Hagerman
- MIND Institute, University of California Davis Health, Sacramento, California, USA
- Department of Pediatrics, University of California Davis, School of Medicine, Sacramento, California, USA
| | - Paul J Hagerman
- Department of Biochemistry and Molecular Medicine, University of California Davis, School of Medicine, One Shields Ave, Davis, CA, USA.
- MIND Institute, University of California Davis Health, Sacramento, California, USA.
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13
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Oh ST, Liu QF, Jeong HJ, Lee S, Samidurai M, Jo J, Pak SC, Park HJ, Kim J, Jeon S. Nasal Cavity Administration of Melanin-Concentrating Hormone Improves Memory Impairment in Memory-Impaired and Alzheimer's Disease Mouse Models. Mol Neurobiol 2019; 56:8076-8086. [PMID: 31183806 DOI: 10.1007/s12035-019-01662-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 05/23/2019] [Indexed: 12/16/2022]
Abstract
Melanin-concentrating hormone (MCH) is a highly conserved neuropeptide known to exhibit important functions in the brain. Some studies have reported that MCH improves memory by promoting memory retention. However, the precise molecular mechanisms by which MCH enhances memory impairment have yet to be fully elucidated. In this study, MCH was administered to the scopolamine-induced memory-impaired mice via the nasal cavity to examine the acute effects of MCH and Alzheimer's disease (AD) mouse models to evaluate the chronic effects of MCH. MCH improved memory impairment in both models and reduced soluble amyloid beta in the cerebral cortex of APP/PS1 transgenic mice. In vitro assays also showed that MCH inhibits amyloid beta-induced cytotoxicity. Furthermore, MCH increased long-term potentiation (LTP) in the hippocampus of wild-type and 5XFAD AD mouse model. To further elucidate the mechanisms of the chronic effect of MCH, the levels of phosphorylated CREB and GSK3β, and the expression of BDNF, TrkB and PSD95 were examined in the cerebral cortex and hippocampus. Our findings indicate that MCH might have neuroprotective effects via downstream pathways associated with the enhancement of neuronal synapses and LTP. This suggests a therapeutic potential of MCH for the treatment of neurodegenerative diseases such as AD.
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Affiliation(s)
- Seung Tack Oh
- Research Institute, Dongkwang Pharmaceutical Company, Ltd., Seoul, 04535, Republic of Korea
| | - Quan Feng Liu
- Department of Neuropsychiatry, Graduate School of Oriental Medicine, Dongguk University, Gyeongju, 38066, Republic of Korea
| | - Ha Jin Jeong
- Department of Child and Adolescent Psychiatry, National Center for Mental Health, Seoul, 04933, Republic of Korea
| | - Seongmi Lee
- Department of Child and Adolescent Psychiatry, National Center for Mental Health, Seoul, 04933, Republic of Korea
| | - Manikandan Samidurai
- Department of Biomedical Sciences, BK21 PLUS Center for Creative Biomedical Scientists at Chonnam National University, Research Institute of Medical Sciences, Chonnam National University Medical School, Gwangju, 61469, Republic of Korea
| | - Jihoon Jo
- Department of Biomedical Sciences, BK21 PLUS Center for Creative Biomedical Scientists at Chonnam National University, Research Institute of Medical Sciences, Chonnam National University Medical School, Gwangju, 61469, Republic of Korea.,NeuroMedical Convergence Lab, Biomedical Research Institute, Chonnam National University Hospital, Gwangju, 61469, Republic of Korea
| | - Sok Cheon Pak
- School of Biomedical Sciences, Charles Sturt University, Bathurst, New South Wales, 2795, Australia
| | - Hi-Joon Park
- Department of Korean Medical Science, Graduate School of Korean Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea. .,Integrative Parkinson's Disease Research Group, Studies of Translational Acupuncture Research (STAR), Acupuncture & Meridian Science Research Center (AMSRC), Kyung Hee University, Seoul, 02447, Republic of Korea.
| | - Jongpil Kim
- Laboratory of Stem Cells & Cell Reprogramming, Department of Chemistry, Dongguk University, Seoul, 04620, Republic of Korea.
| | - Songhee Jeon
- Department of Biomedical Sciences, BK21 PLUS Center for Creative Biomedical Scientists at Chonnam National University, Research Institute of Medical Sciences, Chonnam National University Medical School, Gwangju, 61469, Republic of Korea.
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14
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Yan L, Lonstein JS, Nunez AA. Light as a modulator of emotion and cognition: Lessons learned from studying a diurnal rodent. Horm Behav 2019; 111:78-86. [PMID: 30244030 PMCID: PMC6456444 DOI: 10.1016/j.yhbeh.2018.09.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Revised: 08/13/2018] [Accepted: 09/17/2018] [Indexed: 01/03/2023]
Abstract
Light profoundly affects the behavior and physiology of almost all animals, including humans. One such effect in humans is that the level of illumination during the day positively contributes to affective well-being and cognitive function. However, the neural mechanisms underlying the effects of daytime light intensity on affect and cognition are poorly understood. One barrier for progress in this area is that almost all laboratory animal models studied are nocturnal. There are substantial differences in how light affects nocturnal and diurnal species, e.g., light induces sleep in nocturnal mammals but wakefulness in diurnal ones, like humans. Therefore, the mechanisms through which light modulates affect and cognition must differ between the chronotypes. To further understand the neural pathways mediating how ambient light modulates affect and cognition, our recent work has developed a diurnal rodent model, the Nile grass rat (Arvicanthis niloticus), in which daytime light intensity is chronically manipulated in grass rats housed under the same 12:12 hour light/dark cycle. This simulates lighting conditions during summer-like bright sunny days vs. winter-like dim cloudy days. Our work has revealed that chronic dim daylight intensity results in higher depression- and anxiety-like behaviors, as well as impaired spatial learning and memory. Furthermore, we have found that hypothalamic orexin is a mediator of these effects. A better understanding of how changes in daytime light intensity impinge upon the neural substrates involved in affect and cognition will lead to novel preventive and therapeutic strategies for seasonal affective disorder, as well as for non-seasonal emotional or cognitive impairments associated with light deficiency.
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Affiliation(s)
- Lily Yan
- Department of Psychology & Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA.
| | - Joseph S Lonstein
- Department of Psychology & Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA
| | - Antonio A Nunez
- Department of Psychology & Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA
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15
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Baldo B, Gabery S, Soylu-Kucharz R, Cheong RY, Henningsen JB, Englund E, McLean C, Kirik D, Halliday G, Petersén Å. SIRT1 is increased in affected brain regions and hypothalamic metabolic pathways are altered in Huntington disease. Neuropathol Appl Neurobiol 2018; 45:361-379. [PMID: 30019499 DOI: 10.1111/nan.12514] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 07/11/2018] [Indexed: 01/03/2023]
Abstract
AIMS Metabolic dysfunction is involved in modulating the disease process in Huntington disease (HD) but the underlying mechanisms are not known. The aim of this study was to investigate if the metabolic regulators sirtuins are affected in HD. METHODS Quantitative real-time polymerase chain reactions were used to assess levels of SIRT1-3 and downstream targets in post mortem brain tissue from HD patients and control cases as well as after selective hypothalamic expression of mutant huntingtin (HTT) using recombinant adeno-associated viral vectors in mice. RESULTS We show that mRNA levels of the metabolic regulator SIRT1 are increased in the striatum and the cerebral cortex but not in the less affected cerebellum in post mortem HD brains. Levels of SIRT2 are only increased in the striatum and SIRT3 is not affected in HD. Interestingly, mRNA levels of SIRT1 are selectively increased in the lateral hypothalamic area (LHA) and ventromedial hypothalamus (VMH) in HD. Further analyses of the LHA and VMH confirmed pathological changes in these regions including effects on SIRT1 downstream targets and reduced mRNA levels of orexin (hypocretin), prodynorphin and melanin-concentrating hormone (MCH) in the LHA and of brain-derived neurotrophic factor (BDNF) in the VMH. Analyses after selective hypothalamic expression of mutant HTT suggest that effects on BDNF, orexin, dynorphin and MCH are early and direct, whereas changes in SIRT1 require more widespread expression of mutant HTT. CONCLUSIONS We show that SIRT1 expression is increased in HD-affected brain regions and that metabolic pathways are altered in the HD hypothalamus.
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Affiliation(s)
- B Baldo
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - S Gabery
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - R Soylu-Kucharz
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - R Y Cheong
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - J B Henningsen
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - E Englund
- Division of Oncology and Pathology, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - C McLean
- Department of Pathology, Alfred Hospital, Melbourne, Vic, Australia
| | - D Kirik
- B.R.A.I.N.S. Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - G Halliday
- Brain and Mind Centre, Sydney Medical School, UNSW Medicine and NeuRA, The University of Sydney, Sydney, NSW, Australia
| | - Å Petersén
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
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16
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Bartlett DM, Domínguez D JF, Reyes A, Zaenker P, Feindel KW, Newton RU, Hannan AJ, Slater JA, Eastwood PR, Lazar AS, Ziman M, Cruickshank T. Investigating the relationships between hypothalamic volume and measures of circadian rhythm and habitual sleep in premanifest Huntington's disease. Neurobiol Sleep Circadian Rhythms 2018; 6:1-8. [PMID: 31236517 PMCID: PMC6586591 DOI: 10.1016/j.nbscr.2018.07.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 06/28/2018] [Accepted: 07/02/2018] [Indexed: 01/01/2023] Open
Abstract
Objective Pathological changes within the hypothalamus have been proposed to mediate circadian rhythm and habitual sleep disturbances in individuals with Huntington's disease (HD). However, investigations examining the relationships between hypothalamic volume and circadian rhythm and habitual sleep in individuals with HD are sparse. This study aimed to comprehensively evaluate the relationships between hypothalamic pathology and circadian rhythm and habitual sleep disturbances in individuals with premanifest HD. Methods Thirty-two individuals with premanifest HD and twenty-nine healthy age- and gender-matched controls participated in this dual-site, cross-sectional study. Magnetic resonance imaging scans were performed to evaluate hypothalamic volume. Circadian rhythm and habitual sleep were assessed via measurement of morning and evening cortisol and melatonin levels, wrist-worn actigraphy, the Consensus Sleep Diary and sleep questionnaires. Information on mood, physical activity levels and body composition were also collected. Results Compared to healthy controls, individuals with premanifest HD displayed significantly reduced grey matter volume in the hypothalamus, decreased habitual sleep efficiency and increased awakenings; however, no alterations in morning cortisol or evening melatonin release were noted in individuals with premanifest HD. While differences in the associations between hypothalamic volume and cortisol and melatonin output existed in individuals with premanifest HD compared to healthy controls, no consistent associations were observed between hypothalamic volume and circadian rhythm or habitual sleep outcomes. Conclusion While significant differences in associations between hypothalamic volume and cortisol and melatonin existed between individuals with premanifest HD and healthy controls, no differences in circadian markers were observed between the groups. This suggests that circadian regulation is maintained despite hypothalamic pathology, perhaps via neural compensation. Longitudinal studies are required to further understand the relationships between the hypothalamus and circadian rhythm and habitual sleep disturbances in HD as the disease course lengthens.
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Affiliation(s)
- Danielle M Bartlett
- School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia
| | - Juan F Domínguez D
- School of Psychology, Australian Catholic University, Melbourne, Victoria, Australia
| | - Alvaro Reyes
- Facultad de Ciencias de la Rehabilitacion, Universidad Andres Bello, Santiago, Chile
| | - Pauline Zaenker
- School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia
| | - Kirk W Feindel
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia, Crawley, Western Australia, Australia
| | - Robert U Newton
- Exercise Medicine Research Institute, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia.,University of Queensland Centre for Clinical Research, University of Queensland, Brisbane, Queensland, Australia
| | - Anthony J Hannan
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - James A Slater
- Centre for Sleep Science, School of Human Sciences, Faculty of Science, University of Western Australia, Crawley, Western Australia, Australia
| | - Peter R Eastwood
- Centre for Sleep Science, School of Human Sciences, Faculty of Science, University of Western Australia, Crawley, Western Australia, Australia
| | - Alpar S Lazar
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, Norfolk, United Kingdom
| | - Mel Ziman
- School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia.,School of Biomedical Science, University of Western Australia, Crawley, Western Australia, Australia
| | - Travis Cruickshank
- School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia.,Peron Institute for Neurological and Translational Science, Perth, Western Australia, Australia
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17
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Vercruysse P, Vieau D, Blum D, Petersén Å, Dupuis L. Hypothalamic Alterations in Neurodegenerative Diseases and Their Relation to Abnormal Energy Metabolism. Front Mol Neurosci 2018; 11:2. [PMID: 29403354 PMCID: PMC5780436 DOI: 10.3389/fnmol.2018.00002] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 01/03/2018] [Indexed: 12/11/2022] Open
Abstract
Neurodegenerative diseases (NDDs) are disorders characterized by progressive deterioration of brain structure and function. Selective neuronal populations are affected leading to symptoms which are prominently motor in amyotrophic lateral sclerosis (ALS) or Huntington’s disease (HD), or cognitive in Alzheimer’s disease (AD) and fronto-temporal dementia (FTD). Besides the common existence of neuronal loss, NDDs are also associated with metabolic changes such as weight gain, weight loss, loss of fat mass, as well as with altered feeding behavior. Importantly, preclinical research as well as clinical studies have demonstrated that altered energy homeostasis influences disease progression in ALS, AD and HD, suggesting that identification of the pathways leading to perturbed energy balance might provide valuable therapeutic targets Signals from both the periphery and central inputs are integrated in the hypothalamus, a major hub for the control of energy balance. Recent research identified major hypothalamic changes in multiple NDDs. Here, we review these hypothalamic alterations and seek to identify commonalities and differences in hypothalamic involvement between the different NDDs. These hypothalamic defects could be key in the development of perturbations in energy homeostasis in NDDs and further understanding of the underlying mechanisms might open up new avenues to not only treat weight loss but also to ameliorate overall neurological symptoms.
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Affiliation(s)
- Pauline Vercruysse
- UMR-S 1118, Faculté de Médecine, Institut National de la Santé et de la Recherche Médicale (INSERM), Strasbourg, France.,UMR-S1118, Université de Strasbourg, Strasbourg, France.,Department of Neurology, Ulm University, Ulm, Germany
| | - Didier Vieau
- UMR-S 1172-JPArc, Centre Hospitalier Régional Universitaire de Lille (CHRU de Lille), Alzheimer and Tauopathies, Lille, France
| | - David Blum
- UMR-S 1172-JPArc, Centre Hospitalier Régional Universitaire de Lille (CHRU de Lille), Alzheimer and Tauopathies, Lille, France
| | - Åsa Petersén
- Translational Neuroendocrine Research Unit (TNU), Lund University, Lund, Sweden
| | - Luc Dupuis
- UMR-S 1118, Faculté de Médecine, Institut National de la Santé et de la Recherche Médicale (INSERM), Strasbourg, France.,UMR-S1118, Université de Strasbourg, Strasbourg, France
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18
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Liu F, Chang HC. Physiological links of circadian clock and biological clock of aging. Protein Cell 2017; 8:477-488. [PMID: 28108951 PMCID: PMC5498335 DOI: 10.1007/s13238-016-0366-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 12/20/2016] [Indexed: 12/20/2022] Open
Abstract
Circadian rhythms orchestrate biochemical and physiological processes in living organisms to respond the day/night cycle. In mammals, nearly all cells hold self-sustained circadian clocks meanwhile couple the intrinsic rhythms to systemic changes in a hierarchical manner. The suprachiasmatic nucleus (SCN) of the hypothalamus functions as the master pacemaker to initiate daily synchronization according to the photoperiod, in turn determines the phase of peripheral cellular clocks through a variety of signaling relays, including endocrine rhythms and metabolic cycles. With aging, circadian desynchrony occurs at the expense of peripheral metabolic pathologies and central neurodegenerative disorders with sleep symptoms, and genetic ablation of circadian genes in model organisms resembled the aging-related features. Notably, a number of studies have linked longevity nutrient sensing pathways in modulating circadian clocks. Therapeutic strategies that bridge the nutrient sensing pathways and circadian clock might be rational designs to defy aging.
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Affiliation(s)
- Fang Liu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, China.,University of Chinese Academy of Sciences, Shanghai, 200031, China
| | - Hung-Chun Chang
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, China.
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19
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Metabolic and behavioral effects of mutant huntingtin deletion in Sim1 neurons in the BACHD mouse model of Huntington's disease. Sci Rep 2016; 6:28322. [PMID: 27334347 PMCID: PMC4917832 DOI: 10.1038/srep28322] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 05/31/2016] [Indexed: 02/06/2023] Open
Abstract
Hypothalamic pathology, metabolic dysfunction and psychiatric symptoms are part of Huntington disease (HD), which is caused by an expanded CAG repeat in the huntingtin (HTT) gene. Inactivation of mutant HTT selectively in the hypothalamus prevents the development of metabolic dysfunction and depressive-like behavior in the BACHD mouse model. The hypothalamic paraventricular nucleus (PVN) is implicated in metabolic and emotional control, therefore we here tested whether inactivation of mutant HTT in the PVN affects metabolic and psychiatric manifestations of HD in BACHD mice. BACHD mice were crossed with mice expressing Cre-recombinase under the Sim1 promoter (Sim1-Cre) to inactivate mutant HTT in Sim1 expressing cells, i.e. the PVN of the hypothalamus. We found that inactivation of mutant HTT in Sim1 cells had a sex-specific effect on both the metabolic and the psychiatric phenotype, as these phenotypes were no longer different in male BACHD/Sim1-Cre mice compared to wild-type littermates. We also found a reduced number of GnRH neurons specifically in the anterior hypothalamus and an increased testes weight in male BACHD mice compared to wild-type littermates. Taken together, expression of mutant HTT in Sim1 cells may play a role for the development of metabolic dysfunction and depressive-like behavior in male BACHD mice.
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20
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Mattis J, Sehgal A. Circadian Rhythms, Sleep, and Disorders of Aging. Trends Endocrinol Metab 2016; 27:192-203. [PMID: 26947521 PMCID: PMC4808513 DOI: 10.1016/j.tem.2016.02.003] [Citation(s) in RCA: 198] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 02/05/2016] [Accepted: 02/08/2016] [Indexed: 10/22/2022]
Abstract
Sleep-wake cycles are known to be disrupted in people with neurodegenerative disorders. These findings are now supported by data from animal models for some of these disorders, raising the question of whether the disrupted sleep/circadian regulation contributes to the loss of neural function. As circadian rhythms and sleep consolidation also break down with normal aging, changes in these may be part of what makes aging a risk factor for disorders like Alzheimer's disease (AD). Mechanisms underlying the connection between circadian/sleep dysregulation and neurodegeneration remain unclear, but several recent studies provide interesting possibilities. While mechanistic analysis is under way, it is worth considering treatment of circadian/sleep disruption as a means to alleviate symptoms of neurodegenerative disorders.
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Affiliation(s)
- Joanna Mattis
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - Amita Sehgal
- HHMI, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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21
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Shan L, Dauvilliers Y, Siegel JM. Interactions of the histamine and hypocretin systems in CNS disorders. Nat Rev Neurol 2015; 11:401-13. [PMID: 26100750 DOI: 10.1038/nrneurol.2015.99] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Histamine and hypocretin neurons are localized to the hypothalamus, a brain area critical to autonomic function and sleep. Narcolepsy type 1, also known as narcolepsy with cataplexy, is a neurological disorder characterized by excessive daytime sleepiness, impaired night-time sleep, cataplexy, sleep paralysis and short latency to rapid eye movement (REM) sleep after sleep onset. In narcolepsy, 90% of hypocretin neurons are lost; in addition, two groups reported in 2014 that the number of histamine neurons is increased by 64% or more in human patients with narcolepsy, suggesting involvement of histamine in the aetiology of this disorder. Here, we review the role of the histamine and hypocretin systems in sleep-wake modulation. Furthermore, we summarize the neuropathological changes to these two systems in narcolepsy and discuss the possibility that narcolepsy-associated histamine abnormalities could mediate or result from the same processes that cause the hypocretin cell loss. We also review the changes in the hypocretin and histamine systems, and the associated sleep disruptions, in Parkinson disease, Alzheimer disease, Huntington disease and Tourette syndrome. Finally, we discuss novel therapeutic approaches for manipulation of the histamine system.
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Affiliation(s)
- Ling Shan
- Department of Psychiatry and Brain Research Institute, UCLA School of Medicine, Veterans' Affairs Greater Los Angeles Healthcare System (VA GLAHS), 16111 Plummer Street North Hills, 151A3, CA 91343, USA
| | - Yves Dauvilliers
- Centre de Référence Nationale Maladies Rares, Narcolepsie et Hypersomnie Idiopathique, Département de Neurologie, Hôpital Gui-de-Chauliac, INSERM U1061, 80 avenue Augustin Fliche, Montpellier 34295, France
| | - Jerome M Siegel
- Department of Psychiatry and Brain Research Institute, UCLA School of Medicine, Veterans' Affairs Greater Los Angeles Healthcare System (VA GLAHS), 16111 Plummer Street North Hills, 151A3, CA 91343, USA
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22
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Gallone S, Boschi S, Rubino E, De Martino P, Scarpini E, Galimberti D, Fenoglio C, Acutis PL, Maniaci MG, Pinessi L, Rainero I. Is HCRTR2 a genetic risk factor for Alzheimer's disease? Dement Geriatr Cogn Disord 2015; 38:245-53. [PMID: 24969517 DOI: 10.1159/000359964] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/20/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUNDS/AIMS Alzheimer's disease (AD) is one of the main types of dementia affecting about 50-55% of all demented patients. Sleep disturbances in AD patients are associated with the severity of dementia and are often the primary reason for institutionalization. These sleep problems partly resemble the core symptoms of narcolepsy, a sleep disorder caused by a general loss of the neurotransmitter hypocretin. The aim of our study was to investigate whether genetic variants in the hypocretin (HCRT) and in the hypocretin receptors 1 and 2 (HCRTR1, HCRTR2) genes could modify the occurrence and the clinical features of AD and to examine if these possible variants influence the role of the protein in sleep regulation. METHODS Using a case-control strategy, we genotyped 388 AD patients and 272 controls for 10 SNPs in the HCRT, HCRTR1 and HCRTR2 genes. In order to evaluate which residues belong to the HCRTR2 binding site, we built a molecular model. RESULTS The genotypic and allelic frequencies of the rs2653349 polymorphism were different (χ(2) = 5.77, p = 0.016; χ(2) = 6.728, p = 0.035) between AD patients and controls. The carriage of the G allele was associated with an increased AD risk (OR 2.53; 95% CI 1.10-5.80). No significant differences were found in the distribution of either genotypic or allelic frequencies between cases and controls in the HCRTR1 polymorphisms rs2271933, rs10914456 and rs4949449 and in the HCRTR2 polymorphism rs3122156. CONCLUSION Our data support the hypothesis that the HCRTR2 gene is likely to be a risk factor for AD. The increased risk inferred is quite small, but in the context of a multi-factorial disease, the presence of this polymorphism may significantly contribute to influencing the susceptibility for AD by interacting with other unknown genetic or environmental factors in sleep regulation.
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Affiliation(s)
- Salvatore Gallone
- Neurology II, Department of Neuroscience, University of Turin, Turin, Italy
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Brown JA, Woodworth HL, Leinninger GM. To ingest or rest? Specialized roles of lateral hypothalamic area neurons in coordinating energy balance. Front Syst Neurosci 2015; 9:9. [PMID: 25741247 PMCID: PMC4332303 DOI: 10.3389/fnsys.2015.00009] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 01/15/2015] [Indexed: 12/26/2022] Open
Abstract
Survival depends on an organism’s ability to sense nutrient status and accordingly regulate intake and energy expenditure behaviors. Uncoupling of energy sensing and behavior, however, underlies energy balance disorders such as anorexia or obesity. The hypothalamus regulates energy balance, and in particular the lateral hypothalamic area (LHA) is poised to coordinate peripheral cues of energy status and behaviors that impact weight, such as drinking, locomotor behavior, arousal/sleep and autonomic output. There are several populations of LHA neurons that are defined by their neuropeptide content and contribute to energy balance. LHA neurons that express the neuropeptides melanin-concentrating hormone (MCH) or orexins/hypocretins (OX) are best characterized and these neurons play important roles in regulating ingestion, arousal, locomotor behavior and autonomic function via distinct neuronal circuits. Recently, another population of LHA neurons containing the neuropeptide Neurotensin (Nts) has been implicated in coordinating anorectic stimuli and behavior to regulate hydration and energy balance. Understanding the specific roles of MCH, OX and Nts neurons in harmonizing energy sensing and behavior thus has the potential to inform pharmacological strategies to modify behaviors and treat energy balance disorders.
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Affiliation(s)
- Juliette A Brown
- Department of Pharmacology and Toxicology, Michigan State University East Lansing, MI, USA ; Center for Integrative Toxicology East Lansing, MI, USA
| | | | - Gina M Leinninger
- Center for Integrative Toxicology East Lansing, MI, USA ; Department of Physiology, Michigan State University East Lansing, MI, USA
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Gabery S, Georgiou-Karistianis N, Lundh SH, Cheong RY, Churchyard A, Chua P, Stout JC, Egan GF, Kirik D, Petersén Å. Volumetric analysis of the hypothalamus in Huntington Disease using 3T MRI: the IMAGE-HD Study. PLoS One 2015; 10:e0117593. [PMID: 25659157 PMCID: PMC4319930 DOI: 10.1371/journal.pone.0117593] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 12/29/2014] [Indexed: 12/25/2022] Open
Abstract
Huntington disease (HD) is a fatal neurodegenerative disorder caused by an expanded CAG repeat in the huntingtin gene. Non-motor symptoms and signs such as psychiatric disturbances, sleep problems and metabolic dysfunction are part of the disease manifestation. These aspects may relate to changes in the hypothalamus, an area of the brain involved in the regulation of emotion, sleep and metabolism. Neuropathological and imaging studies using both voxel-based morphometry (VBM) of magnetic resonance imaging (MRI) as well as positron emission tomography (PET) have demonstrated pathological changes in the hypothalamic region during early stages in symptomatic HD. In this investigation, we aimed to establish a robust method for measurements of the hypothalamic volume in MRI in order to determine whether the hypothalamic dysfunction in HD is associated with the volume of this region. Using T1-weighted imaging, we describe a reproducible delineation procedure to estimate the hypothalamic volume which was based on the same landmarks used in histologically processed postmortem hypothalamic tissue. Participants included 36 prodromal HD (pre-HD), 33 symptomatic HD (symp-HD) and 33 control participants who underwent MRI scanning at baseline and 18 months follow-up as part of the IMAGE-HD study. We found no evidence of cross-sectional or longitudinal changes between groups in hypothalamic volume. Our results suggest that hypothalamic pathology in HD is not associated with volume changes.
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Affiliation(s)
- Sanaz Gabery
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | | | - Sofia Hult Lundh
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Rachel Y. Cheong
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Andrew Churchyard
- School of Psychological Sciences, Monash University, Clayton, Victoria, 3180, Australia
- Huntington’s Disease Unit, Bethlehem Hospital, Kooyong Rd, Caulfield, Victoria, 3162, Australia
| | - Phyllis Chua
- Huntington’s Disease Unit, Bethlehem Hospital, Kooyong Rd, Caulfield, Victoria, 3162, Australia
- Department of Psychiatry, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, 3168, Australia
| | - Julie C. Stout
- School of Psychological Sciences, Monash University, Clayton, Victoria, 3180, Australia
| | - Gary F. Egan
- School of Psychological Sciences, Monash University, Clayton, Victoria, 3180, Australia
- Monash Biomedical Imaging (MBI), Monash University, Clayton, Victoria, 3180, Australia
- Life Sciences Computation Centre, Victorian Life Sciences Computation Initiative (VLSCI), Melbourne, Victoria, Australia
| | - Deniz Kirik
- Brain Repair and Imaging in Neural Systems (B.R.A.I.N.S) Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
- Lund University Bioimaging Center, Lund, Sweden
| | - Åsa Petersén
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
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Baldo B, Cheong RY, Petersén Å. Effects of deletion of mutant huntingtin in steroidogenic factor 1 neurons on the psychiatric and metabolic phenotype in the BACHD mouse model of Huntington disease. PLoS One 2014; 9:e107691. [PMID: 25271967 PMCID: PMC4182678 DOI: 10.1371/journal.pone.0107691] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 08/21/2014] [Indexed: 12/27/2022] Open
Abstract
Psychiatric and metabolic features appear several years before motor disturbances in the neurodegenerative Huntington’s disease (HD), caused by an expanded CAG repeat in the huntingtin (HTT) gene. Although the mechanisms leading to these aspects are unknown, dysfunction in the hypothalamus, a brain region controlling emotion and metabolism, has been suggested. A direct link between the expression of the disease causing protein, huntingtin (HTT), in the hypothalamus and the development of metabolic and psychiatric-like features have been shown in the BACHD mouse model of HD. However, precisely which circuitry in the hypothalamus is critical for these features is not known. We hypothesized that expression of mutant HTT in the ventromedial hypothalamus, an area involved in the regulation of metabolism and emotion would be important for the development of these non-motor aspects. Therefore, we inactivated mutant HTT in a specific neuronal population of the ventromedial hypothalamus expressing the transcription factor steroidogenic factor 1 (SF1) in the BACHD mouse using cross-breeding based on a Cre-loxP system. Effects on anxiety-like behavior were assessed using the elevated plus maze and novelty-induced suppressed feeding test. Depressive-like behavior was assessed using the Porsolt forced swim test. Effects on the metabolic phenotype were analyzed using measurements of body weight and body fat, as well as serum insulin and leptin levels. Interestingly, the inactivation of mutant HTT in SF1-expressing neurons exerted a partial positive effect on the depressive-like behavior in female BACHD mice at 4 months of age. In this cohort of mice, no anxiety-like behavior was detected. The deletion of mutant HTT in SF1 neurons did not have any effect on the development of metabolic features in BACHD mice. Taken together, our results indicate that mutant HTT regulates metabolic networks by affecting hypothalamic circuitries that do not involve the SF1 neurons of the ventromedial hypothalamus.
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Affiliation(s)
- Barbara Baldo
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
- * E-mail:
| | - Rachel Y. Cheong
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Åsa Petersén
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
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Baldo B, Soylu R, Petersén Å. Maintenance of basal levels of autophagy in Huntington's disease mouse models displaying metabolic dysfunction. PLoS One 2013; 8:e83050. [PMID: 24376631 PMCID: PMC3869748 DOI: 10.1371/journal.pone.0083050] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 11/07/2013] [Indexed: 11/24/2022] Open
Abstract
Huntington's disease (HD) is a fatal neurodegenerative disorder caused by an expanded polyglutamine repeat in the huntingtin protein. Neuropathology in the basal ganglia and in the cerebral cortex has been linked to the motor and cognitive symptoms whereas recent work has suggested that the hypothalamus might be involved in the metabolic dysfunction. Several mouse models of HD that display metabolic dysfunction have hypothalamic pathology, and expression of mutant huntingtin in the hypothalamus has been causally linked to the development of metabolic dysfunction in mice. Although the pathogenic mechanisms by which mutant huntingtin exerts its toxic functions in the HD brain are not fully known, several studies have implicated a role for the lysososomal degradation pathway of autophagy. Interestingly, changes in autophagy in the hypothalamus have been associated with the development of metabolic dysfunction in wild-type mice. We hypothesized that expression of mutant huntingtin might lead to changes in the autophagy pathway in the hypothalamus in mice with metabolic dysfunction. We therefore investigated whether there were changes in basal levels of autophagy in a mouse model expressing a fragment of 853 amino acids of mutant huntingtin selectively in the hypothalamus using a recombinant adeno-associate viral vector approach as well as in the transgenic BACHD mice. We performed qRT-PCR and Western blot to investigate the mRNA and protein expression levels of selected autophagy markers. Our results show that basal levels of autophagy are maintained in the hypothalamus despite the presence of metabolic dysfunction in both mouse models. Furthermore, although there were no major changes in autophagy in the striatum and cortex of BACHD mice, we detected modest, but significant differences in levels of some markers in mice at 12 months of age. Taken together, our results indicate that overexpression of mutant huntingtin in mice do not significantly perturb basal levels of autophagy.
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Affiliation(s)
- Barbara Baldo
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Rana Soylu
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Åsa Petersén
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
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27
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Decreased Hypothalamic Prohormone Convertase Expression in Huntington Disease Patients. J Neuropathol Exp Neurol 2013; 72:1126-34. [DOI: 10.1097/nen.0000000000000010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Orexin neurons use endocannabinoids to break obesity-induced inhibition. Proc Natl Acad Sci U S A 2013; 110:9625-6. [PMID: 23720305 DOI: 10.1073/pnas.1307389110] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Heese K. G proteins, p60TRP, and neurodegenerative diseases. Mol Neurobiol 2013; 47:1103-11. [PMID: 23345134 DOI: 10.1007/s12035-013-8410-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2012] [Accepted: 01/13/2013] [Indexed: 12/20/2022]
Abstract
Alzheimer's disease (AD) is a complex brain disorder of the limbic system and association cortices. The disease is characterized by the production and deposition of the amyloid β-peptide (Aβ) in the brain, and the neuropathological mechanisms involved must be deciphered to gain further insights into the fundamental aspects of the protein biology responsible for the development and progression of this disease. Aβ is generated by the intramembranous cleavage of the β-amyloid precursor protein, which is mediated by the proteases β- and γ-secretase. Accumulating evidence suggests the importance of the coupling of this cleavage mechanism to G protein signaling. Heterotrimeric G proteins play pivotal roles as molecular switches in signal transduction pathways mediated by G protein-coupled receptors (GPCRs). Extracellular stimuli activate these receptors, which in turn catalyze guanosine triphosphate-guanosine diphosphate exchange on the G protein α-subunit. The activation-deactivation cycles of G proteins underlie their crucial functions as molecular switches for a vast array of biological responses. The novel transcription regulator protein p60 transcription regulator protein and its related GPCR signaling pathways have recently been described as potential targets for the development of alternative strategies for inhibiting the early signaling mechanisms involved in neurodegenerative diseases such as AD.
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Affiliation(s)
- Klaus Heese
- Department of Biomedical Engineering, College of Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Republic of Korea.
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30
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van Wamelen DJ, Aziz NA, Anink JJ, van Steenhoven R, Angeloni D, Fraschini F, Jockers R, Roos RAC, Swaab DF. Suprachiasmatic nucleus neuropeptide expression in patients with Huntington's Disease. Sleep 2013; 36:117-25. [PMID: 23288978 DOI: 10.5665/sleep.2314] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
STUDY OBJECTIVE To study whether sleep and circadian rhythm disturbances in patients with Huntington's disease (HD) arise from dysfunction of the body's master clock, the hypothalamic suprachiasmatic nucleus. DESIGN Postmortem cohort study. PATIENTS Eight patients with HD and eight control subjects matched for sex, age, clock time and month of death, postmortem delay, and fixation time of paraffin-embedded hypothalamic tissue. MEASUREMENTS AND RESULTS Using postmortem paraffin-embedded tissue, we assessed the functional integrity of the suprachiasmatic nucleus in patients with HD and control subjects by determining the expression of two major regulatory neuropeptides, vasoactive intestinal polypeptide and arginine vasopressin. Additionally, we studied melatonin 1 and 2 receptor expression. Compared with control subjects, the suprachiasmatic nucleus contained 85% fewer neurons immunoreactive for vasoactive intestinal polypeptide and 33% fewer neurons for arginine vasopressin in patients with HD (P = 0.002 and P = 0.027). The total amount of vasoactive intestinal polypeptide and arginine vasopressin messenger RNA was unchanged. No change was observed in the number of melatonin 1 or 2 receptor immunoreactive neurons. CONCLUSIONS These findings indicate posttranscriptional neuropeptide changes in the suprachiasmatic nucleus of patients with HD, and suggest that sleep and circadian rhythm disorders in these patients may at least partly arise from suprachiasmatic nucleus dysfunction.
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Affiliation(s)
- Daniel J van Wamelen
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands.
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van Wamelen DJ, Aziz NA, Anink JJ, Roos RAC, Swaab DF. Paraventricular nucleus neuropeptide expression in Huntington's disease patients. Brain Pathol 2012; 22:654-61. [PMID: 22257050 DOI: 10.1111/j.1750-3639.2012.00565.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Neuroendocrine, metabolic and autonomic nervous system dysfunctions are prevalent among patients with Huntington's disease (HD) and may underlie symptoms such as depression, weight loss and autonomic failure. Using post-mortem paraffin-embedded tissue, we assessed the integrity of the major neuropeptide populations in the paraventricular nucleus (PVN)-the hypothalamic neuroendocrine and autonomic integration center-in HD patients. The number corticotropin-releasing hormone, cocaine- and amphetamine-regulated transcript, arginine vasopressin and oxytocin immunoreactive (ir) neurons did not differ between HD patients and control subjects. However, the significant positive correlation between arginine vasopressin and oxytocin ir neurons in control subjects (P = 0.036) was absent in patients. Corticotropin-releasing hormone mRNA levels were 68% higher in HD patients (P = 0.046). Thyrotropin-releasing hormone mRNA levels did not differ between HD patients and control subjects, although a negative correlation with disease duration was present in the former (P = 0.036). These findings indicate that the PVN is largely unaffected in HD patients. However, our findings suggest that hypothalamic-pituitary-thyroid axis activity may alter during the course of the disease and that autonomic nervous system dysfunction might partly arise from an imbalance between arginine vasopressin and oxytocin neurons in the PVN.
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Affiliation(s)
- Daniel J van Wamelen
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam ZO, The Netherlands.
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Aziz NA, Pijl H, Frölich M, Schröder-van der Elst JP, van der Bent C, Roelfsema F, Roos RAC. Delayed onset of the diurnal melatonin rise in patients with Huntington's disease. J Neurol 2012; 256:1961-5. [PMID: 19562249 PMCID: PMC2780627 DOI: 10.1007/s00415-009-5196-1] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2009] [Accepted: 05/24/2009] [Indexed: 11/27/2022]
Abstract
Sleep disturbances are very prevalent in Huntington’s disease (HD) patients and can substantially impair their quality of life. Accumulating evidence suggests considerable dysfunction of the hypothalamic suprachiasmatic nucleus (SCN), the biological clock, in both HD patients and transgenic mouse models of the disease. As melatonin has a major role in the regulation of sleep and other cyclical bodily activities and its synthesis is directly regulated by the SCN, we postulated that disturbed SCN function is likely to give rise to abnormal melatonin secretion in HD. Therefore, we compared 24 h melatonin secretion profiles between early stage HD patients and age-, sex- and body mass index-matched controls. Although mean diurnal melatonin levels were not different between the two groups (p = 0.691), the timing of the evening rise in melatonin levels was significantly delayed by more than 01:30 h in HD patients (p = 0.048). Moreover, diurnal melatonin levels strongly correlated with both motor (r = −0.70, p = 0.036) and functional impairment (r = +0.78, p = 0.013). These findings suggest a delayed sleep phase syndrome-like circadian rhythm disorder in early stage HD patients and suggest that melatonin levels may progressively decline with advancing disease.
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Affiliation(s)
- N Ahmad Aziz
- Department of Neurology, K-05-Q 110, Leiden University Medical Center, P.O. Box 9600, Albinusdreef 2, 2300 RC Leiden, The Netherlands.
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Naidoo N, Zhu J, Zhu Y, Fenik P, Lian J, Galante R, Veasey S. Endoplasmic reticulum stress in wake-active neurons progresses with aging. Aging Cell 2011; 10:640-9. [PMID: 21388495 PMCID: PMC3125474 DOI: 10.1111/j.1474-9726.2011.00699.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Fragmentation of wakefulness and sleep are expected outcomes of advanced aging. We hypothesize that wake neurons develop endoplasmic reticulum dyshomeostasis with aging, in parallel with impaired wakefulness. In this series of experiments, we sought to more fully characterize age-related changes in wakefulness and then, in relevant wake neuronal populations, explore functionality and endoplasmic reticulum homeostasis. We report that old mice show greater sleep/wake transitions in the active period with markedly shortened wake periods, shortened latencies to sleep, and less wake time in the subjective day in response to a novel social encounter. Consistent with sleep/wake instability and reduced social encounter wakefulness, orexinergic and noradrenergic wake neurons in aged mice show reduced c-fos response to wakefulness and endoplasmic reticulum dyshomeostasis with increased nuclear translocation of CHOP and GADD34. We have identified an age-related unfolded protein response injury to and dysfunction of wake neurons. It is anticipated that these changes contribute to sleep/wake fragmentation and cognitive impairment in aging.
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Affiliation(s)
- Nirinjini Naidoo
- Division of Sleep Medicine, Center for Sleep & Circadian Neurobiology, School of Medicine, University of Pennsylvania, 125 S. 31st Street, Philadelphia, PA 19104, USA.
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Sousa-Ferreira L, Álvaro AR, Aveleira C, Santana M, Brandão I, Kügler S, Pereira de Almeida L, Cavadas C. Proliferative hypothalamic neurospheres express NPY, AGRP, POMC, CART and Orexin-A and differentiate to functional neurons. PLoS One 2011; 6:e19745. [PMID: 21589937 PMCID: PMC3092771 DOI: 10.1371/journal.pone.0019745] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2010] [Accepted: 04/15/2011] [Indexed: 01/12/2023] Open
Abstract
Some pathological conditions with feeding pattern alterations, including obesity and Huntington disease (HD) are associated with hypothalamic dysfunction and neuronal cell death. Additionally, the hypothalamus is a neurogenic region with the constitutive capacity to generate new cells of neuronal lineage, in adult rodents. The aim of the present work was to evaluate the expression of feeding-related neuropeptides in hypothalamic progenitor cells and their capacity to differentiate to functional neurons which have been described to be affected by hypothalamic dysfunction. Our study shows that hypothalamic progenitor cells from rat embryos grow as floating neurospheres and express the feeding-related neuropeptides Neuropeptide Y (NPY), Agouti-related Protein (AGRP), Pro-OpioMelanocortin (POMC), Cocaine-and-Amphetamine Responsive Transcript (CART) and Orexin-A/Hypocretin-1. Moreover the relative mRNA expression of NPY and POMC increases during the expansion of hypothalamic neurospheres in proliferative conditions. Mature neurons were obtained from the differentiation of hypothalamic progenitor cells including NPY, AGRP, POMC, CART and Orexin-A positive neurons. Furthermore the relative mRNA expression of NPY, CART and Orexin-A increases after the differentiation of hypothalamic neurospheres. Similarly to the adult hypothalamic neurons the neurospheres-derived neurons express the glutamate transporter EAAT3. The orexigenic and anorexigenic phenotype of these neurons was identified by functional response to ghrelin and leptin hormones, respectively. This work demonstrates the presence of appetite-related neuropeptides in hypothalamic progenitor cells and neurons obtained from the differentiation of hypothalamic neurospheres, including the neuronal phenotypes that have been described by others as being affected by hypothalamic neurodegeneration. These in vitro models can be used to study hypothalamic progenitor cells aiming a therapeutic intervention to mitigate feeding dysfunction that are associated with hypothalamic neurodegeneration.
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Affiliation(s)
- Lígia Sousa-Ferreira
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - Ana Rita Álvaro
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
- Department of Biology and Environment, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - Célia Aveleira
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Magda Santana
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - Inês Brandão
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Sebastian Kügler
- Department of Neurology, Viral Vectors Laboratory, University Medicine Göttingen, Göttingen, Germany
| | - Luís Pereira de Almeida
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - Cláudia Cavadas
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
- * E-mail:
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35
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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.
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Affiliation(s)
- Pablo Torterolo
- Department of Physiology, School of Medicine, University of the Republic Montevideo, Uruguay
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36
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Krolewski DM, Medina A, Kerman IA, Bernard R, Burke S, Thompson RC, Bunney WE, Schatzberg AF, Myers RM, Akil H, Jones EG, Watson SJ. Expression patterns of corticotropin-releasing factor, arginine vasopressin, histidine decarboxylase, melanin-concentrating hormone, and orexin genes in the human hypothalamus. J Comp Neurol 2011; 518:4591-611. [PMID: 20886624 DOI: 10.1002/cne.22480] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The hypothalamus regulates numerous autonomic responses and behaviors. The neuroactive substances corticotropin-releasing factor (CRF), arginine-vasopressin (AVP), histidine decarboxylase (HDC), melanin-concentrating hormone (MCH), and orexin/hypocretins (ORX) produced in the hypothalamus mediate a subset of these processes. Although the expression patterns of these genes have been well studied in rodents, less is known about them in humans. We combined classical histological techniques with in situ hybridization histochemistry to produce both 2D and 3D images and to visually align and quantify expression of the genes for these substances in nuclei of the human hypothalamus. The hypothalamus was arbitrarily divided into rostral, intermediate, and caudal regions. The rostral region, containing the paraventricular nucleus (PVN), was defined by discrete localization of CRF- and AVP-expressing neurons, whereas distinct relationships between HDC, MCH, and ORX mRNA-expressing neurons delineated specific levels within the intermediate and caudal regions. Quantitative mRNA signal intensity measurements revealed no significant differences in overall CRF or AVP expression at any rostrocaudal level of the PVN. HDC mRNA expression was highest at the level of the premammillary area, which included the dorsomedial and tuberomammillary nuclei as well as the dorsolateral hypothalamic area. In addition, the overall intensity of hybridization signal exhibited by both MCH and ORX mRNA-expressing neurons peaked in distinct intermediate and caudal hypothalamic regions. These results suggest that human hypothalamic neurons involved in the regulation of the HPA axis display distinct neurochemical patterns that may encompass multiple local nuclei.
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Affiliation(s)
- David M Krolewski
- Molecular & Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, Michigan 48109, USA
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van Wamelen DJ, Shan L, Aziz NA, Anink JJ, Bao AM, Roos RAC, Swaab DF. Functional increase of brain histaminergic signaling in Huntington's disease. Brain Pathol 2010; 21:419-27. [PMID: 21106039 DOI: 10.1111/j.1750-3639.2010.00465.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
To evaluate whether central histaminergic signaling in Huntington's disease (HD) patients is affected, we assessed mRNA levels of histidine decarboxylase (HDC), volume of and neuron number in the hypothalamic tuberomamillary nucleus (TMN) (HD n = 8, controls n = 8). In addition, we assessed histamine N-methyltransferase (HMT) and histamine receptor (H(1) R, H(2) R and H(3) R) mRNA levels in the inferior frontal gyrus (IFG) (n = 9 and 9) and caudate nucleus (CN) (n = 6 and 6) by real-time polymerase chain reaction. In HD patients, TMN volume and neuronal number was unaltered (P = 0.72, P = 0.25). The levels of HDC mRNA (P = 0.046), IFG HMT (P < 0.001), H(1) R (P < 0.001) and H(3) R mRNA levels (P = 0.011) were increased, while CN H(2) R and H(3) R mRNA levels were decreased (P = 0.041, P = 0.009). In HD patients, we observed a positive correlation between IFG H(3) R mRNA levels and CAG repeat length (P = 0.024) and negative correlations between age at onset of disease and IFG HMT (P = 0.015) and H(1) R (P = 0.021) mRNA levels. These findings indicate a functional increase in brain histaminergic signaling in HD, and provide a rationale for the use of histamine receptor antagonists.
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Affiliation(s)
- Daniel J van Wamelen
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Science, Amsterdam ZO.
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Soneson C, Fontes M, Zhou Y, Denisov V, Paulsen JS, Kirik D, Petersén A. Early changes in the hypothalamic region in prodromal Huntington disease revealed by MRI analysis. Neurobiol Dis 2010; 40:531-43. [PMID: 20682340 DOI: 10.1016/j.nbd.2010.07.013] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Revised: 06/28/2010] [Accepted: 07/22/2010] [Indexed: 11/15/2022] Open
Abstract
Huntington disease (HD) is a fatal neurodegenerative disorder caused by an expanded CAG repeat. Its length can be used to estimate the time of clinical diagnosis, which is defined by overt motor symptoms. Non-motor symptoms begin before motor onset, and involve changes in hypothalamus-regulated functions such as sleep, emotion and metabolism. Therefore we hypothesized that hypothalamic changes occur already prior to the clinical diagnosis. We performed voxel-based morphometry and logistic regression analyses of cross-sectional MR images from 220 HD gene carriers and 75 controls in the Predict-HD study. We show that changes in the hypothalamic region are detectable before clinical diagnosis and that its grey matter contents alone are sufficient to distinguish HD gene carriers from control cases. In conclusion, our study shows, for the first time, that alterations in grey matter contents in the hypothalamic region occur at least a decade before clinical diagnosis in HD using MRI.
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Goodman AOG, Barker RA. How vital is sleep in Huntington’s disease? J Neurol 2010; 257:882-97. [DOI: 10.1007/s00415-010-5517-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Revised: 02/15/2010] [Accepted: 02/25/2010] [Indexed: 01/21/2023]
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Morairty SR, Wisor J, Silveira K, Sinko W, Kilduff TS. The wake-promoting effects of hypocretin-1 are attenuated in old rats. Neurobiol Aging 2009; 32:1514-27. [PMID: 19781813 DOI: 10.1016/j.neurobiolaging.2009.07.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2009] [Revised: 06/01/2009] [Accepted: 07/27/2009] [Indexed: 11/16/2022]
Abstract
Disruption of sleep is a frequent complaint among elderly humans and is also evident in aged laboratory rodents. The neurobiological bases of age-related sleep/wake disruption are unknown. Given the critical role of the hypocretins in sleep/wake regulation, we sought to determine whether the wake-promoting effect of hypocretin changes with age in Wistar rats, a strain in which age-related changes in both sleep and hypocretin signaling have been reported. Intracerebroventricular infusions of hypocretin-1 (10 and 30 μg) significantly increased wake time relative to vehicle in both young (3 mos) and old (25 mos) Wistar rats. However, the magnitude and duration of the wake-promoting effects were attenuated with age. An increase of parameters associated with homeostatic sleep recovery after sleep deprivation, including non-rapid eye movement (NR) sleep time, NR delta power, the ratio of NR to rapid eye movement (REM) sleep, and NR consolidation, occurred subsequent to Hcrt-induced waking in young but not old rats. ICV infusions of hypocretin-2 (10 and 30 μg) produced fewer effects in both young and old rats. These data demonstrate that activation of a major sleep/wake regulatory pathway is attenuated in old rats.
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Weight loss in neurodegenerative disorders. J Neurol 2009; 255:1872-80. [PMID: 19165531 DOI: 10.1007/s00415-009-0062-8] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2008] [Revised: 07/02/2008] [Accepted: 07/11/2008] [Indexed: 10/21/2022]
Abstract
Unintended weight loss frequently complicates the course of many neurodegenerative disorders and can contribute substantially to both morbidity and mortality. This will be illustrated here by reviewing the characteristics of unintended weight loss in the three major neurodegenerative disorders: Alzheimer's disease, Parkinson's disease and Huntington's disease. A common denominator of weight loss in these neurodegenerative disorders is its typically complex pathophysiology. Timely recognition of the underlying pathophysiological process is of crucial importance, since a tailored treatment of weight loss can considerably improve the quality of life. This treatment is, primarily, comprised of a number of methods of increasing energy intake. Moreover, there are indications for defects in the systemic energy homeostasis and gastrointestinal function, which may also serve as therapeutic targets. However, the clinical merits of such interventions have yet to be demonstrated.
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