1
|
Carpi M, Palagini L, Fernandes M, Calvello C, Geoffroy PA, Miniati M, Pini S, Gemignani A, Mercuri NB, Liguori C. Clinical usefulness of dual orexin receptor antagonism beyond insomnia: Neurological and psychiatric comorbidities. Neuropharmacology 2024; 245:109815. [PMID: 38114045 DOI: 10.1016/j.neuropharm.2023.109815] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 12/11/2023] [Accepted: 12/12/2023] [Indexed: 12/21/2023]
Abstract
Orexin is a neurotransmitter produced by a small group of hypothalamic neurons. Besides its well-known role in the regulation of the sleep-wake cycle, the orexin system was shown to be relevant in several physiological functions including cognition, mood and emotion modulation, and energy homeostasis. Indeed, the implication of orexin neurotransmission in neurological and psychiatric diseases has been hypothesized via a direct effect exerted by the projections of orexin neurons to several brain areas, and via an indirect effect through orexin-mediated modulation of sleep and wake. Along with the growing evidence concerning the use of dual orexin receptor antagonists (DORAs) in the treatment of insomnia, studies assessing their efficacy in insomnia comorbid with psychiatric and neurological diseases have been set in order to investigate the potential impact of DORAs on both sleep-related symptoms and disease-specific manifestations. This narrative review aimed at summarizing the current evidence on the use of DORAs in neurological and psychiatric conditions comorbid with insomnia, also discussing the possible implication of modulating the orexin system for improving the burden of symptoms and the pathological mechanisms of these disorders. Target searches were performed on PubMed/MEDLINE and Scopus databases and ongoing studies registered on Clinicaltrials.gov were reviewed. Despite some contradictory findings, preclinical studies seemingly support the possible beneficial role of orexin antagonism in the management of the most common neurological and psychiatric diseases with sleep-related comorbidities. However, clinical research is still limited and further studies are needed for corroborating these promising preliminary results.
Collapse
Affiliation(s)
- Matteo Carpi
- Sleep and Epilepsy Centre, Neurology Unit, University Hospital Tor Vergata, Rome, Italy.
| | - Laura Palagini
- Department of Clinical and Experimental Medicine, Unit of Psychiatry, Azienda Ospedaliero Universitaria Pisana AUOP, Pisa, Italy.
| | - Mariana Fernandes
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy.
| | - Carmen Calvello
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy.
| | - Pierre Alexis Geoffroy
- Département de Psychiatrie et D'addictologie, AP-HP, GHU Paris Nord, DMU Neurosciences, Hopital Bichat - Claude Bernard, F-75018, Paris, France; GHU Paris - Psychiatry & Neurosciences, Paris, France; Université de Paris, NeuroDiderot, Inserm, FHU I2-D2, F-75019, Paris, France.
| | - Mario Miniati
- Department of Clinical and Experimental Medicine, Unit of Psychiatry, Azienda Ospedaliero Universitaria Pisana AUOP, Pisa, Italy.
| | - Stefano Pini
- Department of Clinical and Experimental Medicine, Unit of Psychiatry, Azienda Ospedaliero Universitaria Pisana AUOP, Pisa, Italy.
| | - Angelo Gemignani
- Unit of Psychology, Department of Surgical, Medical and Molecular Pathology and Critical Care Medicine, University of Pisa, Azienda Ospedaliero Universitaria Pisana AUOP, Pisa, Italy.
| | | | - Claudio Liguori
- Sleep and Epilepsy Centre, Neurology Unit, University Hospital Tor Vergata, Rome, Italy; Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy.
| |
Collapse
|
2
|
Jiménez-Jiménez FJ, Alonso-Navarro H, García-Martín E, Agúndez JAG. Sleep Disorders in Patients with Choreic Syndromes. Curr Neurol Neurosci Rep 2023; 23:361-379. [PMID: 37269451 DOI: 10.1007/s11910-023-01274-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2023] [Indexed: 06/05/2023]
Abstract
PURPOSE OF REVIEW Patients with different types of choreic syndromes, specially those with Huntington's (HD) and Wilson's (WD) diseases, report frequent sleep complaints. This review focuses on the main findings of studies addressing the sleep features in these diseases, and other less frequent causes of chorea associated with sleep disorders, including a new syndrome described in the last decade associated with IgLON5 antibodies. RECENT FINDINGS Patients with HD and WD showed a bad quality of sleep and high frequency of insomnia and excessive daytime somnolence. WD patients also showed high scores on a specific scale for rapid eye movement sleep behavior disorders. HD and WD share decreased sleep efficiency and increased REM sleep latencies, percentage of sleep stage N1, and wake after sleep onset (WASO) among their polysomnographic features. Patients with HD and WD showed a high prevalence of different sleep disorders. Patients with other causes of chorea, including neuroacanthocytosis, parasomnia with sleep breathing disorder associated with antibodies to IgLON5, Sydenham's chorea, and choreic syndromes associated to certain genetic mutations show sleep disorders as well.
Collapse
Affiliation(s)
- Félix Javier Jiménez-Jiménez
- Section of Neurology, Hospital Universitario del Sureste, Ronda del Sur 10 E-28500, Arganda del Rey, Madrid, Spain.
| | - Hortensia Alonso-Navarro
- Section of Neurology, Hospital Universitario del Sureste, Ronda del Sur 10 E-28500, Arganda del Rey, Madrid, Spain
| | - Elena García-Martín
- Universidad de Extremadura, University Institute of Molecular Pathology Biomarkers, Cáceres, Spain
| | - José A G Agúndez
- Universidad de Extremadura, University Institute of Molecular Pathology Biomarkers, Cáceres, Spain
| |
Collapse
|
3
|
Ten-Blanco M, Flores Á, Cristino L, Pereda-Pérez I, Berrendero F. Targeting the orexin/hypocretin system for the treatment of neuropsychiatric and neurodegenerative diseases: from animal to clinical studies. Front Neuroendocrinol 2023; 69:101066. [PMID: 37015302 DOI: 10.1016/j.yfrne.2023.101066] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 03/15/2023] [Accepted: 03/30/2023] [Indexed: 04/06/2023]
Abstract
Orexins (also known as hypocretins) are neuropeptides located exclusively in hypothalamic neurons that have extensive projections throughout the central nervous system and bind two different G protein-coupled receptors (OX1R and OX2R). Since its discovery in 1998, the orexin system has gained the interest of the scientific community as a potential therapeutic target for the treatment of different pathological conditions. Considering previous basic science research, a dual orexin receptor antagonist, suvorexant, was the first orexin agent to be approved by the US Food and Drug Administration to treat insomnia. In this review, we discuss and update the main preclinical and human studies involving the orexin system with several psychiatric and neurodegenerative diseases. This system constitutes a nice example of how basic scientific research driven by curiosity can be the best route to the generation of new and powerful pharmacological treatments.
Collapse
Affiliation(s)
- Marc Ten-Blanco
- Faculty of Experimental Sciences, Universidad Francisco de Vitoria, 28223 Pozuelo de Alarcón, Madrid, Spain
| | - África Flores
- Pharmacology Unit, Department of Pathology and Experimental Therapeutics, Neurosciences Institute, University of Barcelona and Bellvitge University Hospital-IDIBELL, 08908 L'Hospitalet de Llobregat, Barcelona, Spain
| | - Luigia Cristino
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry (ICB), National Research Council (CNR), Pozzuoli, Italy
| | - Inmaculada Pereda-Pérez
- Faculty of Experimental Sciences, Universidad Francisco de Vitoria, 28223 Pozuelo de Alarcón, Madrid, Spain
| | - Fernando Berrendero
- Faculty of Experimental Sciences, Universidad Francisco de Vitoria, 28223 Pozuelo de Alarcón, Madrid, Spain.
| |
Collapse
|
4
|
Fronczek R, Schinkelshoek M, Shan L, Lammers GJ. The orexin/hypocretin system in neuropsychiatric disorders: Relation to signs and symptoms. HANDBOOK OF CLINICAL NEUROLOGY 2021; 180:343-358. [PMID: 34225940 DOI: 10.1016/b978-0-12-820107-7.00021-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Hypocretin-1 and 2 (or orexin A and B) are neuropeptides exclusively produced by a group of neurons in the lateral and dorsomedial hypothalamus that project throughout the brain. In accordance with this, the two different hypocretin receptors are also found throughout the brain. The hypocretin system is mainly involved in sleep-wake regulation, but also in reward mechanisms, food intake and metabolism, autonomic regulation including thermoregulation, and pain. The disorder most strongly linked to the hypocretin system is the primary sleep disorder narcolepsy type 1 caused by a lack of hypocretin signaling, which is most likely due to an autoimmune process targeting the hypocretin-producing neurons. However, the hypocretin system may also be affected, but to a lesser extent and less specifically, in various other neurological disorders. Examples are neurodegenerative diseases such as Alzheimer's, Huntington's and Parkinson's disease, immune-mediated disorders such as multiple sclerosis, neuromyelitis optica, and anti-Ma2 encephalitis, and genetic disorders such as type 1 diabetus mellitus and Prader-Willi Syndrome. A partial hypocretin deficiency may contribute to the sleep features of these disorders.
Collapse
Affiliation(s)
- Rolf Fronczek
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands; Sleep Wake Centre SEIN, Heemstede, The Netherlands.
| | - Mink Schinkelshoek
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands; Sleep Wake Centre SEIN, Heemstede, The Netherlands
| | - Ling Shan
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands; Sleep Wake Centre SEIN, Heemstede, The Netherlands; Department Neuropsychiatric Disorders, Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands
| | - Gert Jan Lammers
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands; Sleep Wake Centre SEIN, Heemstede, The Netherlands
| |
Collapse
|
5
|
Circadian alterations in patients with neurodegenerative diseases: Neuropathological basis of underlying network mechanisms. Neurobiol Dis 2020; 144:105029. [PMID: 32736083 DOI: 10.1016/j.nbd.2020.105029] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 06/19/2020] [Accepted: 07/23/2020] [Indexed: 01/16/2023] Open
Abstract
Circadian organization of physiology and behavior is an important biological process that allows organisms to anticipate and prepare for daily changes and demands. Disruptions in this system precipitates a wide range of health issues. In patients with neurodegenerative diseases, alterations of circadian rhythms are among the most common and debilitating symptoms. Although a growing awareness of these symptoms has occurred during the last decade, their underlying neuropathophysiological circuitry remains poorly understood and consequently no effective therapeutic strategies are available to alleviate these health issues. Recent studies have examined the neuropathological status of the different neural components of the circuitry governing the generation of circadian rhythms in neurodegenerative diseases. In this review, we will dissect the potential contribution of dysfunctions in the different nodes of this circuitry to circadian alterations in patients with neurodegenerative diseases. A deeper understanding of these mechanisms will provide not only a better understanding of disease neuro-pathophysiology, but also hold the promise for developing effective and mechanisms-based therapies.
Collapse
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
Al-Kuraishy HM, Abdulhadi MH, Hussien NR, Al-Niemi MS, Rasheed HA, Al-Gareeb AI. Involvement of orexinergic system in psychiatric and neurodegenerative disorders: A scoping review. Brain Circ 2020; 6:70-80. [PMID: 33033776 PMCID: PMC7511915 DOI: 10.4103/bc.bc_42_19] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 02/20/2020] [Accepted: 03/20/2020] [Indexed: 12/12/2022] Open
Abstract
Orexin is a neuropeptide secreted from lateral hypothalamus and pre-frontal cortex concerned in the wakefulness and excitement. This study aimed to review the possible neurobiological effect of orexin. A diversity of search strategies was adopted and assumed which included electronic database searches of Medline and PubMed using MeSH terms, keywords, and title words during the search. Orexin plays a vital role in activation of learning, memory acquisition, and consolidation through activation of monoaminergic system, which affect cognitive flexibility and cognitive function. Orexin stimulates adrenocorticotropin and corticosteroid secretions via activation of central corticotropin-releasing hormone. Cerebrospinal fluid (CSF) and serum orexin serum levels are reduced in depression, schizophrenia, and narcolepsy. However, high orexin serum levels are revealed in drug addictions. Regarding neurodegenerative brain diseases, CSF and serum orexin serum levels are reduced Parkinson disease, Alzheimer dementia, Huntington's disease, amyotrphic lateral sclerosis, and multiple sclerosis. Orexin antagonist leads to significant reduction of sympathetic over-activity during withdrawal syndrome. As well, orexin antagonist improves sleep pattern. Orexinergic system is involved in the different psychiatric and neurological disorders; therefore, targeting of this system could be possible novel pathway in the management of these disorders. In addition, measurement of CSF and serum orexin levels might predict the relapse and withdrawal of addict patients.
Collapse
Affiliation(s)
- Hayder M Al-Kuraishy
- Department of Pharmacology, Toxicology and Medicine, College of Medicine Almustansiriya University, Baghdad, Iraq
| | - May H Abdulhadi
- Department of Pharmacology, Toxicology and Medicine, College of Medicine Almustansiriya University, Baghdad, Iraq
| | - Nawar R Hussien
- Department of Pharmacology, Toxicology and Medicine, College of Medicine Almustansiriya University, Baghdad, Iraq
| | - Marwa S Al-Niemi
- Department of Pharmacology, Toxicology and Medicine, College of Medicine Almustansiriya University, Baghdad, Iraq
| | - Huda A Rasheed
- Department of Pharmacology, Toxicology and Medicine, College of Medicine Almustansiriya University, Baghdad, Iraq
| | - Ali I Al-Gareeb
- Department of Pharmacology, Toxicology and Medicine, College of Medicine Almustansiriya University, Baghdad, Iraq
| |
Collapse
|
8
|
Orexins role in neurodegenerative diseases: From pathogenesis to treatment. Pharmacol Biochem Behav 2020; 194:172929. [PMID: 32315694 DOI: 10.1016/j.pbb.2020.172929] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 04/07/2020] [Accepted: 04/08/2020] [Indexed: 12/12/2022]
Abstract
Orexin is a neurotransmitter that mainly regulates sleep/wake cycle. In addition to its sleep cycle regulatory role, it is involved in regulation of attention, energy homeostasis, neurogenesis and cognition. Several evidences has shown the involvement of orexin in narcolepsy, but there are also growing evidences that shows the disturbance in orexin system in neurodegenerative diseases including Alzheimer's, Parkinson's, Epilepsy, Huntington's diseases and Amyotrophic lateral sclerosis. Pathogenesis and clinical symptoms of these disorders can be partly attributed from orexin system imbalance. However, there are controversial reports on the exact relationship between orexin and these neurodegenerative diseases. Therefore, the aim of this review is to summarize the current evidences regarding the role of orexin in these neurodegenerative diseases.
Collapse
|
9
|
Cabanas M, Pistono C, Puygrenier L, Rakesh D, Jeantet Y, Garret M, Cho YH. Neurophysiological and Behavioral Effects of Anti-Orexinergic Treatments in a Mouse Model of Huntington's Disease. Neurotherapeutics 2019; 16:784-796. [PMID: 30915710 PMCID: PMC6694444 DOI: 10.1007/s13311-019-00726-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Huntington's disease (HD) is associated with sleep and circadian disturbances in addition to hallmark motor and cognitive impairments. Electrophysiological studies on HD mouse models have revealed an aberrant oscillatory activity at the beta frequency, during sleep, that is associated with HD pathology. Moreover, HD animal models display an abnormal sleep-wake cycle and sleep fragmentation. In this study, we investigated a potential involvement of the orexinergic system dysfunctioning in sleep-wake and circadian disturbances and abnormal network (i.e., beta) activity in the R6/1 mouse model. We found that the age at which orexin activity starts to deviate from normal activity pattern coincides with that of sleep disturbances as well as the beta activity. We also found that acute administration of Suvorexant, an orexin 1 and orexin 2 receptor antagonist, was sufficient to decrease the beta power significantly and to improve sleep in R6/1 mice. In addition, a 5-day treatment paradigm alleviated cognitive deficits and induced a gain of body weight in female HD mice. These results suggest that restoring normal activity of the orexinergic system could be an efficient therapeutic solution for sleep and behavioral disturbances in HD.
Collapse
Affiliation(s)
- Magali Cabanas
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, CNRS UMR 5287, Allee Geoffroy St Hilaire, CS 50023, 33615, Pessac Cedex, France
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, University of Bordeaux, Bordeaux, France
| | - Cristiana Pistono
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, CNRS UMR 5287, Allee Geoffroy St Hilaire, CS 50023, 33615, Pessac Cedex, France
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, University of Bordeaux, Bordeaux, France
| | - Laura Puygrenier
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, CNRS UMR 5287, Allee Geoffroy St Hilaire, CS 50023, 33615, Pessac Cedex, France
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, University of Bordeaux, Bordeaux, France
| | - Divyangana Rakesh
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, CNRS UMR 5287, Allee Geoffroy St Hilaire, CS 50023, 33615, Pessac Cedex, France
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, University of Bordeaux, Bordeaux, France
| | - Yannick Jeantet
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, CNRS UMR 5287, Allee Geoffroy St Hilaire, CS 50023, 33615, Pessac Cedex, France
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, University of Bordeaux, Bordeaux, France
| | - Maurice Garret
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, CNRS UMR 5287, Allee Geoffroy St Hilaire, CS 50023, 33615, Pessac Cedex, France
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, University of Bordeaux, Bordeaux, France
| | - Yoon H Cho
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, CNRS UMR 5287, Allee Geoffroy St Hilaire, CS 50023, 33615, Pessac Cedex, France.
- Institute of Cognitive and Integrative Neuroscience of Aquitaine, University of Bordeaux, Bordeaux, France.
| |
Collapse
|
10
|
Zeun P, Scahill RI, Tabrizi SJ, Wild EJ. Fluid and imaging biomarkers for Huntington's disease. Mol Cell Neurosci 2019; 97:67-80. [PMID: 30807825 DOI: 10.1016/j.mcn.2019.02.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 01/25/2019] [Accepted: 02/12/2019] [Indexed: 01/18/2023] Open
Abstract
Huntington's disease is a chronic progressive neurodegenerative condition for which there is no disease-modifying treatment. The known genetic cause of Huntington's disease makes it possible to identify individuals destined to develop the disease and instigate treatments before the onset of symptoms. Multiple trials are already underway that target the cause of HD, yet clinical measures are often insensitive to change over typical clinical trial duration. Robust biomarkers of drug target engagement, disease severity and progression are required to evaluate the efficacy of treatments and concerted efforts are underway to achieve this. Biofluid biomarkers have potential advantages of direct quantification of biological processes at the molecular level, whilst imaging biomarkers can quantify related changes at a structural level in the brain. The most robust biofluid and imaging biomarkers can offer complementary information, providing a more comprehensive evaluation of disease stage and progression to inform clinical trial design and endpoints.
Collapse
Affiliation(s)
- Paul Zeun
- Huntington's Disease Centre, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom.
| | - Rachael I Scahill
- Huntington's Disease Centre, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom.
| | - Sarah J Tabrizi
- Huntington's Disease Centre, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom.
| | - Edward J Wild
- Huntington's Disease Centre, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom.
| |
Collapse
|
11
|
Black SW, Sun JD, Santiago P, Laihsu A, Kimura N, Yamanaka A, Bersot R, Humphries PS. Partial ablation of the orexin field induces a sub-narcoleptic phenotype in a conditional mouse model of orexin neurodegeneration. Sleep 2018; 41:5025920. [DOI: 10.1093/sleep/zsy116] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 05/29/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Sarah Wurts Black
- In Vivo Biology Department, Reset Therapeutics, South San Francisco, CA
| | - Jessica D Sun
- In Vivo Biology Department, Reset Therapeutics, South San Francisco, CA
| | - Pamela Santiago
- In Vivo Biology Department, Reset Therapeutics, South San Francisco, CA
| | - Alex Laihsu
- In Vivo Biology Department, Reset Therapeutics, South San Francisco, CA
| | - Nikki Kimura
- In Vivo Biology Department, Reset Therapeutics, South San Francisco, CA
| | - Akihiro Yamanaka
- Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Ross Bersot
- In Vivo Biology Department, Reset Therapeutics, South San Francisco, CA
| | - Paul S Humphries
- In Vivo Biology Department, Reset Therapeutics, South San Francisco, CA
| |
Collapse
|
12
|
Santiago JCP, Otto M, Kern W, Baier PC, Hallschmid M. Relationship between cerebrospinal fluid concentrations of orexin A/hypocretin-1 and body composition in humans. Peptides 2018; 102:26-30. [PMID: 29471000 DOI: 10.1016/j.peptides.2018.02.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 01/23/2018] [Accepted: 02/16/2018] [Indexed: 12/17/2022]
Abstract
The hypothalamic neuropeptide orexin A (hypocretin-1) is a key signal in sleep/wake regulation and promotes food intake. We investigated the relationship between cerebrospinal fluid orexin A concentrations and body composition in non-narcoleptic human subjects with a wide range of body weight to gain insight into the role of orexin A in human metabolism. We collected cerebrospinal fluid and blood samples and measured body composition by bioelectric impedance analysis in 36 subjects (16 women and 20 men) with body mass indices between 16.24 and 38.10 kg/m2 and an age range of 19-80 years. Bivariate Pearson correlations and stepwise multiple regressions were calculated to determine associations between orexin A and body composition as well as biometric variables. Concentrations of orexin A in cerebrospinal fluid averaged 315.6 ± 6.0 pg/ml, were comparable between sexes (p > 0.15) and unrelated to age (p > 0.66); they appeared slightly reduced in overweight/obese compared to normal-weight subjects (p = .07). Orexin A concentrations decreased with body weight (r = -0.38, p = .0229) and fat-free mass (r = -0.39, p = .0173) but were not linked to body fat mass (p > 0.24). They were inversely related to total body water (r = -0.39, p = .0174) as well as intracellular (r = -0.41, p = .0139) and extracellular water (r = -0.35, p = .0341). Intracellular water was the only factor independently associated with cerebrospinal fluid orexin A concentrations (p = .0139). We conclude that cerebrospinal fluid orexin A concentrations do not display associations with body adiposity, but are inversely related to intracellular water content. These cross-sectional findings suggest a link between orexin A signaling and the regulation of water homeostasis in humans.
Collapse
Affiliation(s)
- João C P Santiago
- Department of Medical Psychology and Behavioral Neurobiology, University of Tübingen, 72076 Tübingen, Germany; German Center for Diabetes Research (DZD), 72076 Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, 72076 Tübingen, Germany.
| | - Markus Otto
- Department of Neurology, University of Ulm, 89081 Ulm, Germany.
| | | | - Paul Christian Baier
- Department of Psychiatry and Psychotherapy, University of Kiel, 24103 Kiel, Germany.
| | - Manfred Hallschmid
- Department of Medical Psychology and Behavioral Neurobiology, University of Tübingen, 72076 Tübingen, Germany; German Center for Diabetes Research (DZD), 72076 Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, 72076 Tübingen, Germany.
| |
Collapse
|
13
|
Abstract
Hypersomnia is a common complaint in many patients with neurodegenerative diseases and a major cause of decreased quality of life. This article discusses the prevalence and factors associated with hypersomnia in patients with a variety of neurodegenerative diseases affecting the central nervous system, including tauopathies, synucleinopathies, and other conditions. Common nocturnal sleep problems that may result in daytime hypersomnia are delineated. A clinical approach to hypersomnia in patients with neurodegenerative diseases, recommended diagnostic testing, and available treatment options are also discussed.
Collapse
Affiliation(s)
- Sushanth Bhat
- Division of Sleep Medicine, Department of Neuroscience, JFK Neuroscience Institute, Seton Hall University, 65 James Street, Edison, NJ 08818, USA.
| | - Sudhansu Chokroverty
- Division of Sleep Medicine, Department of Neuroscience, JFK Neuroscience Institute, Seton Hall University, 65 James Street, Edison, NJ 08818, USA
| |
Collapse
|
14
|
Byrne LM, Wild EJ. Cerebrospinal Fluid Biomarkers for Huntington’s Disease. J Huntingtons Dis 2016; 5:1-13. [DOI: 10.3233/jhd-160196] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
15
|
Abstract
Sleep-wake disruption is frequently observed and often one of the earliest reported symptoms of many neurodegenerative disorders. This provides insight into the underlying pathophysiology of these disorders, as sleep-wake abnormalities are often accompanied by neurodegenerative or neurotransmitter changes. However, in addition to being a symptom of the underlying neurodegenerative condition, there is also emerging evidence that sleep disturbance itself may contribute to the development and facilitate the progression of several of these disorders. Due to its impact both as an early symptom and as a potential factor contributing to ongoing neurodegeneration, the sleep-wake cycle is an ideal target for further study for potential interventions not only to lessen the burden of these diseases but also to slow their progression. In this review, we will highlight the sleep phenotypes associated with some of the major neurodegenerative disorders, focusing on the circadian disruption associated with Alzheimer's disease, the rapid eye movement behavior disorder and sleep fragmentation associated with Parkinson's disease, and the insomnia and circadian dysregulation associated with Huntington's disease.
Collapse
Affiliation(s)
- Sabra M Abbott
- Department of Neurology, Northwestern Feinberg School of Medicine, Chicago, IL, USA
| | - Aleksandar Videnovic
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
16
|
Abstract
In this review, we explore the similarities and differences in the behavioural neurobiology found in the mouse models of Huntington's disease (HD) and the human disease state. The review is organised with a comparative focus on the functional domains of motor control, cognition and behavioural disturbance (akin to psychiatric disturbance in people) and how our knowledge of the underlying physiological changes that are manifest in the HD mouse lines correspond to those seen in the HD clinical population. The review is framed in terms of functional circuitry and neurotransmitter systems and how abnormalities in these systems impact on the behavioural readouts across the mouse lines and how these may correspond to the deficits observed in people. In addition, interpretational issues associated with the data from animal studies are discussed.
Collapse
Affiliation(s)
- Simon P Brooks
- Brain Repair Group, Division of Neuroscience, Cardiff University School of Bioscience, Museum Avenue, Cardiff, Wales, UK,
| | | |
Collapse
|
17
|
Sleep in Neurodegenerative Diseases. Sleep Med 2015. [DOI: 10.1007/978-1-4939-2089-1_32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
18
|
Chen Q, de Lecea L, Hu Z, Gao D. The hypocretin/orexin system: an increasingly important role in neuropsychiatry. Med Res Rev 2014; 35:152-97. [PMID: 25044006 DOI: 10.1002/med.21326] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Hypocretins, also named as orexins, are excitatory neuropeptides secreted by neurons specifically located in lateral hypothalamus and perifornical areas. Orexinergic fibers are extensively distributed in various brain regions and involved in a number of physiological functions, such as arousal, cognition, stress, appetite, and metabolism. Arousal is the most important function of orexin system as dysfunction of orexin signaling leads to narcolepsy. In addition to narcolepsy, orexin dysfunction is associated with serious neural disorders, including addiction, depression, and anxiety. However, some results linking orexin with these disorders are still contradictory, which may result from differences of detection methods or the precision of tools used in measurements; strategies targeted to orexin system (e.g., antagonists to orexin receptors, gene delivery, and cell transplantation) are promising new tools for treatment of neuropsychiatric disorders, though studies are still in a stage of preclinical or clinical research.
Collapse
Affiliation(s)
- Quanhui Chen
- Department of Physiology, Third Military Medical University, Chongqing 400038, China; Department of Sleep and Psychology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400038, China
| | | | | | | |
Collapse
|
19
|
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.
Collapse
Affiliation(s)
- Klaus Heese
- Department of Biomedical Engineering, College of Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Republic of Korea.
| |
Collapse
|
20
|
Boethel CD, Jones SF, Barker JA. Sleep Movement Disorders and Neurologic Movement Disorders. Sleep Med Clin 2012. [DOI: 10.1016/j.jsmc.2012.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
21
|
Morton AJ. Circadian and sleep disorder in Huntington's disease. Exp Neurol 2012; 243:34-44. [PMID: 23099415 DOI: 10.1016/j.expneurol.2012.10.014] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 09/27/2012] [Accepted: 10/16/2012] [Indexed: 01/18/2023]
Abstract
Huntington's disease is a progressive neurological disorder that starts insidiously with motor, cognitive or psychiatric disturbance, and progresses through a distressing range of symptoms to end with a devastating loss of function, both motor and executive. There is a growing awareness that, in addition to cognitive and psychiatric symptoms, there are other important non-motor symptoms in HD, including sleep and circadian abnormalities. It is not clear if sleep-wake changes are caused directly by HD gene-related pathology, or if they are simply a consequence of having a neurodegenerative disease. From a patient point of view, the answer is irrelevant, since sleep and circadian disturbances are deleterious to good daily living, even in neurologically normal people. The assumption should be that, at the very least, sleep and/or circadian disturbance in HD patients will contribute to their symptoms. At worst, they may contribute to the progressive decline in HD. Here I review the state of our understanding of sleep and circadian abnormalities in HD. I also outline a set of simple rules that can be followed to improve the chances of a good night's sleep, since preventing any 'preventable' symptoms is the a logical first step in treating disease. The long-term impact of sleep disruption in HD is unknown. There have been no large-scale systematic studies of in sleep in HD. Furthermore, there has never been a study of the efficacy of pharmaceuticals that are typically used to treat sleep deficits in HD patients. Thus treatment of sleep disturbance in HD is necessarily empirical. A better understanding of the relationship between sleep/circadian abnormalities and HD pathology is needed, if treatment of this aspect of HD is to be optimized.
Collapse
Affiliation(s)
- A Jennifer Morton
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK.
| |
Collapse
|
22
|
Abstract
Huntington's disease is an autosomal dominant, progressive neurodegenerative disorder, for which there is no disease-modifying treatment. By use of predictive genetic testing, it is possible to identify individuals who carry the gene defect before the onset of symptoms, providing a window of opportunity for intervention aimed at preventing or delaying disease onset. However, without robust and practical measures of disease progression (ie, biomarkers), the efficacy of therapeutic interventions in this premanifest Huntington's disease population cannot be readily assessed. Current progress in the development of biomarkers might enable evaluation of disease progression in individuals at the premanifest stage of the disease; these biomarkers could be useful in defining endpoints in clinical trials in this population. Clinical, cognitive, neuroimaging, and biochemical biomarkers are being investigated for their potential in clinical use and their value in the development of future treatments for patients with Huntington's disease.
Collapse
Affiliation(s)
- David W Weir
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada
| | | | | |
Collapse
|
23
|
Williams RH, Morton AJ, Burdakov D. Paradoxical function of orexin/hypocretin circuits in a mouse model of Huntington's disease. Neurobiol Dis 2011; 42:438-45. [PMID: 21324360 PMCID: PMC5767114 DOI: 10.1016/j.nbd.2011.02.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Revised: 02/04/2011] [Accepted: 02/07/2011] [Indexed: 10/18/2022] Open
Abstract
Huntington's disease (HD) is a neurodegenerative disorder involving progressive motor disturbances, cognitive decline, and desynchronized sleep-wake rhythms. Recent studies revealed that restoring normal sleep-wake cycles can improve cognitive function in HD mice, suggesting that some sleep/wake systems remain operational and thus represent potential therapeutic targets for HD. Hypothalamic neurons expressing orexins/hypocretins (orexin neurons) are fundamental orchestrators of arousal in mammals, but it is unclear whether orexin circuits operate normally in HD. Here we analyzed the electrophysiology, histology, and gene expression of orexin circuits in brain slices from R6/2 mice, a transgenic model of HD with a progressive neurological phenotype. We report that in R6/2 mice, the size of an electrically distinct subpopulation of orexin neurons is reduced, as is the number of orexin-immunopositive cells in some hypothalamic regions. R6/2 orexin cells display altered glutamatergic inputs, and have an abnormal circadian profile of activity, despite normal circadian rhythmicity of the suprachiasmatic nucleus (SCN), the "master clock" of the brain. Nevertheless, even at advanced stages of HD, intrinsic firing properties of orexin cells remain normal and suppressible by serotonin, noradrenaline, and glucose. Furthermore, histaminergic neurons (key cells required for the propagation of orexin-induced arousal) also display normal responses to orexin. Together, these data suggest that the orexin system remains functional and modifiable in HD mice, although its circadian activity profile is disrupted and no longer follows that of the SCN.
Collapse
Affiliation(s)
- Rhîannan H. Williams
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK
| | - A. Jennifer Morton
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK
| | - Denis Burdakov
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK
| |
Collapse
|
24
|
Abstract
Parkinson's (PD) and Huntington's disease (HD) are chronic neurodegenerative conditions of the brain with a variety of clinical presentations including a disorder of movement and a range of nonmotor deficits. HD is genetic in origin and the causative gene and protein known, namely mutant Huntingtin, which leads to widespread early neuronal dysfunction and death throughout the brain. In contrast, the etiology of sporadic PD is unknown, and the pathology targets the nigrostriatal dopaminergic neurons with the formation of alpha-synuclein positive Lewy bodies. In both diseases, the ability to accurately diagnose the disease in the early stages and monitor progression over time remains a major challenge given the majority of the pathology is sited deep within the CNS. This challenge has gained extra significance as the development of disease-modifying drugs starts to emerge into the clinic. To this end, there is a need to find biomarkers that will help in the accurate diagnosis of the disease and/or prediction of its clinical onset as well as biomarkers that are able to faithfully track disease progression independent of any symptomatic effects of any therapies. In addition, these same markers may also help stratify each of these heterogeneous disorders into specific subtypes that share particular clinical and pathological characteristics.
Collapse
Affiliation(s)
- Gráinne C O'Keeffe
- Cambridge Centre for Brain Repair, Department of Clinical Neuroscience, University of Cambridge, Cambridge CB2 0PY, United Kingdom.
| | | | | |
Collapse
|
25
|
Bathen-Nöthen A, Heider C, Fernandez A, Beineke A, Sewell A, Otto M, Tipold A. Hypocretin Measurement in an Icelandic Foal with Narcolepsy. J Vet Intern Med 2009; 23:1299-302. [DOI: 10.1111/j.1939-1676.2009.0400.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
|
26
|
|
27
|
Bourgin P, Zeitzer JM, Mignot E. CSF hypocretin-1 assessment in sleep and neurological disorders. Lancet Neurol 2008; 7:649-62. [DOI: 10.1016/s1474-4422(08)70140-6] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
28
|
Aziz A, Fronczek R, Maat-Schieman M, Unmehopa U, Roelandse F, Overeem S, van Duinen S, Lammers GJ, Swaab D, Roos R. Hypocretin and melanin-concentrating hormone in patients with Huntington disease. Brain Pathol 2008; 18:474-83. [PMID: 18498421 DOI: 10.1111/j.1750-3639.2008.00135.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
To evaluate whether hypocretin-1 (orexin-A) and melanin-concentrating hormone (MCH) neurotransmission are affected in patients with Huntington disease (HD), we immunohistochemically stained hypocretin and MCH neurons and estimated their total numbers in the lateral hypothalamus of both HD patients and matched controls. In addition, hypocretin-1 levels were determined in prefrontal cortical tissue and post-mortem ventricular cerebrospinal fluid (CSF) using a radioimmunoassay. The total number of hypocretin-1 neurons was significantly reduced by 30% in HD brains (P = 0.015), while the total number of MCH neurons was not significantly altered (P = 0.100). Levels of hypocretin-1 were 33% lower in the prefrontal cortex of the HD patients (P = 0.025), but ventricular CSF levels were similar to the control values (P = 0.306). Neuronal intranuclear and cytoplasmic inclusions of mutant huntingtin were present in all HD hypothalami, although with a variable distribution across different hypothalamic structures. We found a specific reduction in hypocretin signaling in patients with HD as MCH cell number was not significantly affected. It remains to be shown whether the moderate decrease in hypocretin neurotransmission could contribute to clinical symptoms. As the number of MCH-expressing neurons was not affected, alterations in MCH signaling are unlikely to have clinical effects in HD patients.
Collapse
Affiliation(s)
- Ahmad Aziz
- Department of Neurology, Leiden University Medical Centre, Leiden, the Netherlands.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Aziz NA, Swaab DF, Pijl H, Roos RAC. Hypothalamic dysfunction and neuroendocrine and metabolic alterations in Huntington's disease: clinical consequences and therapeutic implications. Rev Neurosci 2007; 18:223-51. [PMID: 18019608 DOI: 10.1515/revneuro.2007.18.3-4.223] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Huntington's disease (HD) is a hereditary neurodegenerative disorder characterized by cognitive, psychiatric, behavioural and motor disturbances. Although the course of HD is also frequently complicated by unintended weight loss, sleep disturbances and autonomic nervous system dysfunction, the aetiology of these signs and symptoms remains largely unknown. In recent years, many novel findings from both animal and human studies have emerged that indicate considerable hypothalamic, endocrine and metabolic alterations in HD. However, a comprehensive overview of these findings is lacking and their precise clinical significance is far from clear. Therefore, in this review we attempt to put these recent developments in the field into perspective by integrating them with previous findings in a comprehensible manner, and by discussing their clinical relevance, with a special focus on body weight, sleep and autonomic functions in HD, which will also allow for the identification of future lines of research in this area.
Collapse
Affiliation(s)
- N A Aziz
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands.
| | | | | | | |
Collapse
|
30
|
Abstract
Huntington's disease (HD) is a hereditary and fatal disorder caused by an expanded CAG triplet repeat in the HD gene, resulting in a mutant form of the protein huntingtin. Wild-type and mutant huntingtin are expressed in most tissues of the body but the normal function of huntingtin is not fully known. In HD, the neuropathology is characterized by intranuclear and cytoplasmic inclusions of huntingtin aggregates, and cell death primarily in striatum and cerebral cortex. However, hypothalamic atrophy occurs at early stages of HD with loss of orexin- and somatostatin-containing cell populations. Several symptoms of HD such as sleep disturbances, alterations in circadian rhythm, and weight loss may be due to hypothalamic dysfunction. Endocrine changes including increased cortisol levels, reduced testosterone levels and increased prevalence of diabetes are found in HD patients. In HD mice, alterations in the hypothalamic-pituitary-adrenal axis occurs as well as pancreatic beta-cell and adipocyte dysfunction. Increasing evidence points towards important pathology of the hypothalamus and the endocrine system in HD. As many neuroendocrine factors are secreted into the cerebrospinal fluid, blood and urine, it is possible that their levels may reflect the disease state in the central nervous system. Investigating neuroendocrine changes in HD opens up the possibility of finding biomarkers to evaluate future therapies for HD, as well as of identifying novel targets for therapeutic interventions.
Collapse
Affiliation(s)
- Asa Petersén
- Neuronal Survival Unit, Department of Experimental Medical Science, Wallenberg Neuroscience Center, BMC A10, 22184 Lund, Sweden.
| | | |
Collapse
|
31
|
Björkqvist M, Petersén A, Nielsen J, Ecker D, Mulder H, Hayden MR, Landwehrmeyer B, Brundin P, Leavitt BR. Cerebrospinal fluid levels of orexin-A are not a clinically useful biomarker for Huntington disease. Clin Genet 2006; 70:78-9. [PMID: 16813610 DOI: 10.1111/j.1399-0004.2006.00636.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|