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Earley CJ, Jones BC, Ferré S. Brain-iron deficiency models of restless legs syndrome. Exp Neurol 2022; 356:114158. [PMID: 35779614 PMCID: PMC9357217 DOI: 10.1016/j.expneurol.2022.114158] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 06/24/2022] [Accepted: 06/25/2022] [Indexed: 11/04/2022]
Abstract
Restless legs syndrome (RLS) is a common sensorimotor disorder for which two main pathological elements are fairly well accepted: Brain iron deficiency (BID) and an altered dopaminergic system. The ability to better understand the causal and consequential factors related to these two pathological elements, would hopefully lead to the development of better therapeutic strategies for treating, if not curing, this disease. The current understanding of the relationship between these two elements is that BID leads to some alterations in neurotransmitters and subsequent changes in the dopaminergic system. Therefore, rodent models based on diet-induced BID, provide a biological substrate to understand the consequences of BID on dopaminergic pathway and on alternative pathways that may be involved. In this review, we present the current research on dopaminergic changes found in RLS subjects and compare that to what is seen in the BID rodent model to provide a validation of the BID rodent model. We also demonstrate the ability of the BID model to predict changes in other neurotransmitter systems and how that has led to new treatment options. Finally, we will present arguments for the utility of recombinant inbred mouse strains that demonstrate natural variation in brain iron, to explore the genetic basis of altered brain iron homeostasis as a model to understand why in idiopathic RLS there can exist a BID despite normal peripheral iron store. This review is the first to draw on 25 years of human and basic research into the pathophysiology of RLS to provide strong supportive data as to the validity of BID model as an important translational model of the disease. As we will demonstrate here, not only does the BID model closely and accurately mimic what we see in the dopaminergic system of RLS, it is the first model to identify alternative systems from which new treatments have recently been developed.
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Affiliation(s)
- Christopher J Earley
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Byron C Jones
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Sergi Ferré
- Integrative Neurobiology Section, National Institutes of Health/National Institute on Drug Abuse, Baltimore, MD, USA
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2
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Franco B, Mota DS, Daubian-Nosé P, Rodrigues NDA, Simino LADP, de Fante T, Bezerra RMN, Manchado Gobatto FDB, Manconi M, Torsoni AS, Esteves AM. Iron deficiency in pregnancy: Influence on sleep, behavior, and molecular markers of adult male offspring. J Neurosci Res 2021; 99:3325-3338. [PMID: 34651324 DOI: 10.1002/jnr.24968] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 08/17/2021] [Accepted: 08/31/2021] [Indexed: 12/14/2022]
Abstract
Iron restriction during pregnancy can lead to iron deficiency and changes in the dopaminergic system in the adulthood of offspring, and restless legs syndrome (RLS) is closely related to these changes. Objectives: Analyze whether iron restriction during pregnancy would cause changes in the behavior, sleep, and dopaminergic system of the male offspring. In addition, we aimed to assess whether exercise would be able to modulate these variables. The pregnant rats (Wistar) were divided into four groups with different concentrations of iron in the diet: standard (St), supplementation (Su), restriction since weaning (R1), and restriction only during pregnancy (R2). After birth, the offspring were assigned to their respective groups according to the dams diet (St, Su, R1, and R2) and distributed into sedentary (SD) and exercised (EX) (for 8 weeks of training), reaching eight groups of offspring (O): OSt SD, OSt EX, OSu SD, OSu EX, OR1 SD, OR1 EX, OR2 SD, and OR2 EX. Sleep, behavior, and analysis of key genes of dopaminergic system (D2, DAT) were performed after 8 weeks. The results for trained offspring that the mother received supplementation diet were the most expressive, with increased freezing and the OR1 SD group showed an increase in DAT protein content. These changes may have been due to the association between the dams diet during pregnancy and the practice of exercise by the offspring. The different concentrations of iron during pregnancy caused changes in the offspring, however, they were not associated with fetal programming in the context of RLS.
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Affiliation(s)
- Beatriz Franco
- Faculdade de Ciências Aplicadas, Universidade Estadual de Campinas, Campinas, Brazil
| | - Diego Silva Mota
- Faculdade de Ciências Aplicadas, Universidade Estadual de Campinas, Limeira, Brazil
| | - Paulo Daubian-Nosé
- Faculdade de Ciências Aplicadas, Universidade Estadual de Campinas, Limeira, Brazil
| | | | | | - Thaís de Fante
- Faculdade de Ciências Aplicadas, Universidade Estadual de Campinas, Limeira, Brazil
| | | | - Fúlvia de Barros Manchado Gobatto
- Faculdade de Ciências Aplicadas, Universidade Estadual de Campinas, Campinas, Brazil.,Faculdade de Ciências Aplicadas, Universidade Estadual de Campinas, Limeira, Brazil
| | - Mauro Manconi
- Sleep and Epilepsy Center, Neurocenter of Southern Switzerland, Civic Hospital of Lugano (EOC), Lugano, Switzerland
| | | | - Andrea Maculano Esteves
- Faculdade de Ciências Aplicadas, Universidade Estadual de Campinas, Campinas, Brazil.,Faculdade de Ciências Aplicadas, Universidade Estadual de Campinas, Limeira, Brazil
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3
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Lyu S, Xing H, DeAndrade MP, Perez PD, Yokoi F, Febo M, Walters AS, Li Y. The Role of BTBD9 in the Cerebellum, Sleep-like Behaviors and the Restless Legs Syndrome. Neuroscience 2020; 440:85-96. [PMID: 32446853 DOI: 10.1016/j.neuroscience.2020.05.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 04/27/2020] [Accepted: 05/14/2020] [Indexed: 12/28/2022]
Abstract
Recent genome-wide association studies (GWAS) have found cerebellum as a top hit for sleep regulation. Restless legs syndrome (RLS) is a sleep-related sensorimotor disorder characterized by uncomfortable sensations in the extremities, generally at night, which are often relieved by movements. Clinical studies have found that RLS patients have structural and functional abnormalities in the cerebellum. However, whether and how cerebellar pathology contributes to sleep regulation and RLS is not known. GWAS identified polymorphisms in BTBD9 conferring a higher risk of sleep disruption and RLS. Knockout of the BTBD9 homolog in mice (Btbd9) and fly results in motor restlessness and sleep disruption. We performed manganese-enhanced magnetic resonance imaging on the Btbd9 knockout mice and found decreased neural activities in the cerebellum, especially in lobules VIII, X, and the deep cerebellar nuclei. Electrophysiological recording of Purkinje cells (PCs) from Btbd9 knockout mice revealed an increased number of non-tonic PCs. Tonic PCs showed increased spontaneous activity and intrinsic excitability. To further investigate the cerebellar contribution to RLS and sleep-like behaviors, we generated PC-specific Btbd9 knockout mice (Btbd9 pKO) and performed behavioral studies. Btbd9 pKO mice showed significant motor restlessness during the rest phase but not in the active phase. Btbd9 pKO mice also had an increased probability of waking at rest. Unlike the Btbd9 knockout mice, there was no increased thermal sensation in the Btbd9 pKO. Our results indicate that the Btbd9 knockout influences the PC activity; dysfunction in the cerebellum may contribute to the motor restlessness found in the Btbd9 knockout mice.
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Affiliation(s)
- Shangru Lyu
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Hong Xing
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Mark P DeAndrade
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Pablo D Perez
- Department of Psychiatry, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Fumiaki Yokoi
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Marcelo Febo
- Department of Psychiatry, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Arthur S Walters
- Division of Sleep Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Yuqing Li
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA.
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4
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Lyu S, DeAndrade MP, Unger EL, Mueller S, Oksche A, Walters AS, Li Y. Mu opioid receptor knockout mouse: Phenotypes with implications on restless legs syndrome. J Neurosci Res 2020; 98:1532-1548. [PMID: 32424971 DOI: 10.1002/jnr.24637] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 04/12/2020] [Accepted: 04/17/2020] [Indexed: 12/19/2022]
Abstract
Restless legs syndrome (RLS) is characterized by an irresistible need to move the legs while sitting or lying at night with insomnia as a frequent consequence. Human RLS has been associated with abnormalities in the endogenous opioid system, the dopaminergic system, the iron regulatory system, anemia, and inflammatory and auto-immune disorders. Our previous work indicates that mice lacking all three subtypes of opioid receptors have a phenotype similar to that of human RLS. To study the roles of each opioid receptor subtype in RLS, we first used mu opioid receptor knockout (MOR KO) mice based on our earlier studies using postmortem brain and cell culture. The KO mice showed decreased hemoglobin, hematocrit, and red blood cells (RBCs), with an appearance of microcytic RBCs indicating anemia. Together with decreased serum iron and transferrin, but increased ferritin levels, the anemia is similar to that seen with chronic inflammation in humans. A decreased serum iron level was also observed in the wildtype mice treated with an MOR antagonist. Iron was increased in the liver and spleen of the KO mice. Normal circadian variations in the dopaminergic and serotoninergic systems were absent in the KO mice. The KO mice showed hyperactivity and increased thermal sensitivity in wakefulness primarily during what would normally be the sleep phase similar to that seen in human RLS. Deficits in endogenous opioid system transmission could predispose to anemia of inflammation and loss of circadian variations in dopaminergic or serotonergic systems, thereby contributing to an RLS-like phenotype.
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Affiliation(s)
- Shangru Lyu
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Mark P DeAndrade
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Erica L Unger
- Department of Biology, Lebanon Valley College, Annville, PA, USA
| | | | - Alexander Oksche
- Mundipharma Research Limited, Cambridge, UK.,Rudolf-Buchheim-Institut für Pharmakologie, University of Giessen, Giessen, Germany
| | - Arthur S Walters
- Division of Sleep Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Yuqing Li
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA
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5
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Lai YY, Hsieh KC, Cheng YH, Chew KT, Nguyen D, Ramanathan L, Siegel JM. Striatal histamine mechanism in the pathogenesis of restless legs syndrome. Sleep 2020; 43:5610750. [PMID: 31671173 PMCID: PMC8491621 DOI: 10.1093/sleep/zsz223] [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: 11/14/2018] [Revised: 03/07/2019] [Indexed: 11/13/2022] Open
Abstract
STUDY OBJECTIVES Restless legs syndrome (RLS) has been hypothesized to be generated by abnormal striatal dopamine transmission. Dopaminergic drugs are effective for the treatment of RLS. However, long-term use of dopaminergic drugs causes adverse effects. We used iron-deficient (ID) and iron-replacement (IR) rats to address the neuropathology of RLS and to determine if a histamine H3 receptor (H3R) antagonist might be a useful treatment. Histamine H3R antagonists have been shown to decrease motor activity. METHODS Control and ID rats were surgically implanted with electrodes for polysomnographic recording. After 3 days of baseline polysomnographic recordings, rats were systemically injected with the H3R agonist, α-methylhistamine, and antagonist, thioperamide. Recordings were continued after drug injection. Striatal H3R levels from control, ID, and IR rats were determined by western blots. Blood from control, ID, and IR rats was collected for the measurement of hematocrit levels. RESULTS α-Methylhistamine and thioperamide increased and decreased motor activity, respectively, in control rats. In ID rats, α-methylhistamine had no effect on motor activity, whereas thioperamide decreased periodic leg movement (PLM) in sleep. Sleep-wake states were not significantly altered under any conditions. Striatal H3R levels were highest in ID rats, moderate to low in IR rats, and lowest in control rats. Striatal H3R levels were also found to positively and negatively correlate with PLM in sleep and hematocrit levels, respectively. CONCLUSIONS A striatal histamine mechanism may be involved in ID anemia-induced RLS. Histamine H3R antagonists may be useful for the treatment of RLS.
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Affiliation(s)
- Yuan-Yang Lai
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA
| | - Kung-Chiao Hsieh
- Veterans Administration Greater Los Angeles HealthCare System (VAGLAHS), Sepulveda, Los Angeles, CA
| | - Yu-Hsuan Cheng
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA
| | - Keng-Tee Chew
- Veterans Administration Greater Los Angeles HealthCare System (VAGLAHS), Sepulveda, Los Angeles, CA
| | - Darian Nguyen
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA
| | - Lalini Ramanathan
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA
| | - Jerome M Siegel
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA.,Veterans Administration Greater Los Angeles HealthCare System (VAGLAHS), Sepulveda, Los Angeles, CA
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6
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Lyu S, DeAndrade MP, Mueller S, Oksche A, Walters AS, Li Y. Hyperactivity, dopaminergic abnormalities, iron deficiency and anemia in an in vivo opioid receptors knockout mouse: Implications for the restless legs syndrome. Behav Brain Res 2019; 374:112123. [PMID: 31376441 DOI: 10.1016/j.bbr.2019.112123] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 07/24/2019] [Accepted: 07/30/2019] [Indexed: 12/13/2022]
Abstract
Previous studies have uncovered a potential role of the opioid system in iron hemostasis and dopamine metabolism. Abnormalities in both of these systems have been noted in human RLS. Autopsy studies of human RLS have shown an endogenous opioid deficiency in the thalamus. Opioids, particularly prolonged-release oxycodone/naloxone, have been approved in Europe to be a second-line therapy for severe restless legs syndrome (RLS). To study the role of opioid receptors in the pathogenesis of RLS, we used a triple knockout (KO) mouse strain that lack mu, delta, and kappa opioid receptors and explored the behavioral and biochemical parameters relevant to RLS. The triple KO mice showed hyperactivity and a trend of increased probability of waking during the rest period (day) akin to that in human RLS (night). Surprisingly, triple KO mice also exhibit decreased serum iron concentration, evidence of anemia, a significant dysfunction in dopamine metabolism akin to that noted in human RLS, as well as an increased latency in response to thermal stimuli. To our knowledge, this is the first study to demonstrate that the endogenous opioid system may play a role in iron metabolism and subsequently in the pathogenesis of anemia. It is also the first study showing that opioid receptors are involved in the production of motor restlessness with a circadian predominance. Our findings support the role of endogenous opioids in the pathogenesis of RLS, and the triple KO mice can be used to understand the relationship between iron deficiency, anemia, dopaminergic dysfunction, and RLS.
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Affiliation(s)
- Shangru Lyu
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Mark P DeAndrade
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Stefan Mueller
- Mundipharma Research GmbH & Co. KG, Höhenstraße 10, Limburg, Germany
| | - Alexander Oksche
- Mundipharma Research Limited, Cambridge, UK; Rudolf-Buchheim-Institut für Pharmakologie, University of Giessen, Giessen, Germany
| | - Arthur S Walters
- Division of Sleep Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Yuqing Li
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA.
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7
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Yousaf T, Pagano G, Wilson H, Politis M. Neuroimaging of Sleep Disturbances in Movement Disorders. Front Neurol 2018; 9:767. [PMID: 30323786 PMCID: PMC6141751 DOI: 10.3389/fneur.2018.00767] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 08/23/2018] [Indexed: 01/18/2023] Open
Abstract
Sleep dysfunction is recognized as a distinct clinical manifestation in movement disorders, often reported early on in the disease course. Excessive daytime sleepiness, rapid eye movement sleep behavior disorder and restless leg syndrome, amidst several others, are common sleep disturbances that often result in significant morbidity. In this article, we review the spectrum of sleep abnormalities across atypical Parkinsonian disorders including multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS), as well as Parkinson's disease (PD) and Huntington's disease (HD). We also explore the current concepts on the neurobiological underpinnings of sleep disorders, including the role of dopaminergic and non-dopaminergic pathways, by evaluating the molecular, structural and functional neuroimaging evidence based on several novel techniques including magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI), single-photon emission computed tomography (SPECT) and positron emission tomography (PET). Based on the current state of research, we suggest that neuroimaging is an invaluable tool for assessing structural and functional correlates of sleep disturbances, harboring the ability to shed light on the sleep problems attached to the limited treatment options available today. As our understanding of the pathophysiology of sleep and wake disruption heightens, novel therapeutic approaches are certain to transpire.
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Affiliation(s)
- Tayyabah Yousaf
- Neurodegeneration Imaging Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Gennaro Pagano
- Neurodegeneration Imaging Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Heather Wilson
- Neurodegeneration Imaging Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Marios Politis
- Neurodegeneration Imaging Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
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8
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Ferini-Strambi L, Carli G, Casoni F, Galbiati A. Restless Legs Syndrome and Parkinson Disease: A Causal Relationship Between the Two Disorders? Front Neurol 2018; 9:551. [PMID: 30087647 PMCID: PMC6066514 DOI: 10.3389/fneur.2018.00551] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 06/19/2018] [Indexed: 11/13/2022] Open
Abstract
Restless Legs Syndrome/Willis-Ekbom Disease (RLS/WED) is a common sleep related movement disorder that can be idiopathic or occurs in comorbidity with other medical conditions such as polyneuropathy, iron deficiency anemia, multiple sclerosis, hypertension and cardiovascular diseases. In recent years, a growing body of literature investigated the association between RLS/WED and Parkinson's Disease (PD). Several questions regarding the comorbidity between these two disorders are still unanswered. If the insurgence of RLS/WED may precede the onset of PD, or if RLS/WED could represent a secondary condition of PD and if impaired dopaminergic pathway may represent a bridge between these two conditions are still debatable issues. In this review, we critically discuss the relationship between RLS/WED and PD by reviewing cross sectional and longitudinal studies, as well as the role of dopamine in these disorders. A twofold interpretation have to be taken into account: dopaminergic therapy may have a crucial role in the development of RLS/WED in PD patients or RLS/WED can be conceived as an early manifestation of PD rather than a risk factor. Several studies showed a high prevalence of RLS/WED in PD patients and several findings related to dopaminergic and iron alterations in both disorders, however up to now it is difficult to find a point of agreement between studies. A greater number of systematic and strongly controlled longitudinal studies as well as basic pathophysiological investigations particularly in RLS/WED are needed to clarify this complex relationship.
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Affiliation(s)
- Luigi Ferini-Strambi
- Department of Clinical Neurosciences, IRCCS San Raffaele Scientific Institute, Neurology - Sleep Disorders Center, Milan, Italy.,Università Vita-Salute San Raffaele, Milan, Italy
| | - Giulia Carli
- Department of Clinical Neurosciences, IRCCS San Raffaele Scientific Institute, Neurology - Sleep Disorders Center, Milan, Italy
| | - Francesca Casoni
- Department of Clinical Neurosciences, IRCCS San Raffaele Scientific Institute, Neurology - Sleep Disorders Center, Milan, Italy
| | - Andrea Galbiati
- Department of Clinical Neurosciences, IRCCS San Raffaele Scientific Institute, Neurology - Sleep Disorders Center, Milan, Italy.,Università Vita-Salute San Raffaele, Milan, Italy
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9
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Rizzo G, Plazzi G. Neuroimaging Applications in Restless Legs Syndrome. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2018; 143:31-64. [DOI: 10.1016/bs.irn.2018.09.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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10
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Zhuo Y, Wu Y, Xu Y, Lu L, Li T, Wang X, Li K. Combined resting state functional magnetic resonance imaging and diffusion tensor imaging study in patients with idiopathic restless legs syndrome. Sleep Med 2017; 38:96-103. [DOI: 10.1016/j.sleep.2017.06.033] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 06/23/2017] [Accepted: 06/27/2017] [Indexed: 11/16/2022]
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11
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Lai Y, Cheng Y, Hsieh K, Nguyen D, Chew K, Ramanathan L, Siegel JM. Motor hyperactivity of the iron-deficient rat - an animal model of restless legs syndrome. Mov Disord 2017; 32:1687-1693. [PMID: 28843017 PMCID: PMC5759344 DOI: 10.1002/mds.27133] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 07/13/2017] [Accepted: 07/16/2017] [Indexed: 02/06/2023] Open
Abstract
Background Abnormal striatal dopamine transmission has been hypothesized to cause restless legs syndrome. Dopaminergic drugs are commonly used to treat restless legs syndrome. However, they cause adverse effects with long‐term use. An animal model would allow the systematic testing of potential therapeutic drugs. A high prevalence of restless legs syndrome has been reported in iron‐deficient anemic patients. We hypothesized that the iron‐deficient animal would exhibit signs similar to those in restless legs syndrome patients. Methods After baseline polysomnographic recordings, iron‐deficient rats received pramipexole injection. Then, iron‐deficient rats were fed a standard rodent diet, and polysomnographic recording were performed for 2 days each week for 4 weeks. Results Iron‐deficient rats have low hematocrit levels and show signs of restless legs syndrome: sleep fragmentation and periodic leg movements in wake and in slow‐wave sleep. Iron‐deficient rats had a positive response to pramipexole treatment. After the iron‐deficient rats were fed the standard rodent diet, hematocrit returned to normal levels, and sleep quality improved, with increased average duration of wake and slow‐wave sleep episodes. Periodic leg movements decreased during both waking and sleep. Hematocrit levels positively correlated with the average duration of episodes in wake and in slow‐wave sleep and negatively correlated with periodic leg movements in wake and in sleep. Western blot analysis showed that striatal dopamine transporter levels were higher in iron‐deficient rats. Conclusions The iron‐deficient rat is a useful animal model of iron‐deficient anemic restless legs syndrome. © 2017 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society
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Affiliation(s)
- Yuan‐Yang Lai
- Department of Psychiatry and Biobehavioral SciencesUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Yu‐Hsuan Cheng
- Department of Psychiatry and Biobehavioral SciencesUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Kung‐Chiao Hsieh
- Department of Psychiatry and Biobehavioral SciencesUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Darian Nguyen
- Department of Psychiatry and Biobehavioral SciencesUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Keng‐Tee Chew
- Department of Psychiatry and Biobehavioral SciencesUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Lalini Ramanathan
- Department of Psychiatry and Biobehavioral SciencesUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Jerome M. Siegel
- Department of Psychiatry and Biobehavioral SciencesUniversity of California, Los AngelesLos AngelesCaliforniaUSA
- Veterans Administration Greater Los Angeles HealthCare SystemSepulveda, Los AngelesLos AngelesCaliforniaUSA
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12
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Yousaf T, Wilson H, Politis M. Imaging the Nonmotor Symptoms in Parkinson's Disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2017; 133:179-257. [PMID: 28802921 DOI: 10.1016/bs.irn.2017.05.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Parkinson's disease is acknowledged to be a multisystem syndrome, manifesting as a result of multineuropeptide dysfunction, including dopaminergic, cholinergic, serotonergic, and noradrenergic deficits. This multisystem disorder ultimately leads to the presentation of a range of nonmotor symptoms, now appreciated to be an integral part of the disease-specific spectrum of symptoms, often preceding the diagnosis of motor Parkinson's disease. In this chapter, we review the dopaminergic and nondopaminergic basis of these symptoms by exploring the neuroimaging evidence based on several techniques including positron emission tomography, single-photon emission computed tomography molecular imaging, magnetic resonance imaging, functional magnetic resonance imaging, and diffusion tensor imaging. We discuss the role of these neuroimaging techniques in elucidating the underlying pathophysiology of NMS in Parkinson's disease.
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Affiliation(s)
- Tayyabah Yousaf
- Neurodegeneration Imaging Group, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London, London, United Kingdom
| | - Heather Wilson
- Neurodegeneration Imaging Group, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London, London, United Kingdom
| | - Marios Politis
- Neurodegeneration Imaging Group, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London, London, United Kingdom.
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13
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Abstract
Sleep disturbances and disorders are common during pregnancy, and they can be risk factors for a number of serious pregnancy-related sleep disorders. These include postpartum depression, pregnancy-induced hypertension, gestational diabetes, and intrauterine growth retardation. In addition, certain chronic sleep disorders, such as narcolepsy, are quite challenging to manage in the context of pregnancy and during lactation, particularly with medications that can be teratogenic. This review discusses 4 common sleep disorders and their impacts on pregnancy, and suggests ways to deal with these disorders that improves maternal and fetal outcomes safely. The review discusses diagnosis and treatment of obstructive sleep apnea, restless legs syndrome, insomnia, and narcolepsy in pregnancy.
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Affiliation(s)
- Margaret Kay-Stacey
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Hrayr P. Attarian
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
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14
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Qamar MA, Sauerbier A, Politis M, Carr H, Loehrer PA, Chaudhuri KR. Presynaptic dopaminergic terminal imaging and non-motor symptoms assessment of Parkinson's disease: evidence for dopaminergic basis? NPJ Parkinsons Dis 2017; 3:5. [PMID: 28649605 PMCID: PMC5445592 DOI: 10.1038/s41531-016-0006-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 11/04/2016] [Accepted: 11/25/2016] [Indexed: 02/08/2023] Open
Abstract
Parkinson's disease (PD) is now considered to be a multisystemic disorder consequent on multineuropeptide dysfunction including dopaminergic, serotonergic, cholinergic, and noradrenergic systems. This multipeptide dysfunction leads to expression of a range of non-motor symptoms now known to be integral to the concept of PD and preceding the diagnosis of motor PD. Some non-motor symptoms in PD may have a dopaminergic basis and in this review, we investigate the evidence for this based on imaging techniques using dopamine-based radioligands. To discuss non-motor symptoms we follow the classification as outlined by the validated PD non-motor symptoms scale.
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Affiliation(s)
- MA Qamar
- National Parkinson’s Foundation International Center of Excellence, King’s College London and King’s College Hospital NHS Foundation Trust, London, UK
| | - A Sauerbier
- National Parkinson’s Foundation International Center of Excellence, King’s College London and King’s College Hospital NHS Foundation Trust, London, UK
| | - M Politis
- Neurodegeneration Imaging Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King’s College London, London, UK
| | - H Carr
- National Parkinson’s Foundation International Center of Excellence, King’s College London and King’s College Hospital NHS Foundation Trust, London, UK
| | - P A Loehrer
- National Parkinson’s Foundation International Center of Excellence, King’s College London and King’s College Hospital NHS Foundation Trust, London, UK
- Department of Neurology, University Hospital Cologne, Cologne, Germany
| | - K Ray Chaudhuri
- National Parkinson’s Foundation International Center of Excellence, King’s College London and King’s College Hospital NHS Foundation Trust, London, UK
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Rizzo G, Li X, Galantucci S, Filippi M, Cho YW. Brain imaging and networks in restless legs syndrome. Sleep Med 2016; 31:39-48. [PMID: 27838239 DOI: 10.1016/j.sleep.2016.07.018] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Revised: 07/08/2016] [Accepted: 07/12/2016] [Indexed: 01/18/2023]
Abstract
Several studies provide information useful to our understanding of restless legs syndrome (RLS), using various imaging techniques to investigate different aspects putatively involved in the pathophysiology of RLS, although there are discrepancies between these findings. The majority of magnetic resonance imaging (MRI) studies using iron-sensitive sequences supports the presence of a diffuse, but regionally variable low brain-iron content, mainly at the level of the substantia nigra, but there is increasing evidence of reduced iron levels in the thalamus. Positron emission tomography (PET) and single positron emission computed tomography (SPECT) findings mainly support dysfunction of dopaminergic pathways involving not only the nigrostriatal but also mesolimbic pathways. None or variable brain structural or microstructural abnormalities have been reported in RLS patients; reports are slightly more consistent concerning levels of white matter. Most of the reported changes were in regions belonging to sensorimotor and limbic/nociceptive networks. Functional MRI studies have demonstrated activation or connectivity changes in the same networks. The thalamus, which includes different sensorimotor and limbic/nociceptive networks, appears to have lower iron content, metabolic abnormalities, dopaminergic dysfunction, and changes in activation and functional connectivity. Summarizing these findings, the primary change could be the reduction of brain iron content, which leads to dysfunction of mesolimbic and nigrostriatal dopaminergic pathways, and in turn to a dysregulation of limbic and sensorimotor networks. Future studies in RLS should evaluate the actual causal relationship among these findings, better investigate the role of neurotransmitters other than dopamine, focus on brain networks by connectivity analysis, and test the reversibility of the different imaging findings following therapy.
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Affiliation(s)
- Giovanni Rizzo
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy; Unit of Neurology, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
| | - Xu Li
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA; Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sebastiano Galantucci
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Massimo Filippi
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy; Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Yong Won Cho
- Department of Neurology, School of Medicine, Dongsan Medical Center, Keimyung University, Daegu, South Korea.
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Koo BB, Bagai K, Walters AS. Restless Legs Syndrome: Current Concepts about Disease Pathophysiology. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2016; 6:401. [PMID: 27536462 PMCID: PMC4961894 DOI: 10.7916/d83j3d2g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 06/07/2016] [Indexed: 01/31/2023]
Abstract
Background In the past few decades, much has been learned about the pathophysiology of restless legs syndrome (RLS). Investigators have studied neuropathology, imaging, electrophysiology, and genetics of RLS, identifying brain regions and biological systems affected in RLS. This manuscript will review RLS pathophysiology literature, examining the RLS state through consideration of the neuroanatomy, then the biological, organ, and genetic systems. Methods Pubmed (1966 to April 2016) was searched for the term “restless legs syndrome” cross-referenced with “pathophysiology,” “pathogenesis,” “pathology,” or “imaging.” English language papers were reviewed. Studies that focused on RLS in relation to another disease were not reviewed. Results Although there are no gross structural brain abnormalities in RLS, widespread brain areas are activated, including the pre- and post-central gyri, cingulate cortex, thalamus, and cerebellum. Pathologically, the most consistent finding is striatal iron deficiency in RLS patients. A host of other biological systems are also altered in RLS, including the dopaminergic, oxygen-sensing, opioid, glutamatergic, and serotonergic systems. Polymorphisms in genes including BTBD9 and MEIS1 are associated with RLS. Discussion RLS is a neurologic sensorimotor disorder that involves pathology, most notably iron deficiency, in motor and sensory brain areas. Brain areas not subserving movement or sensation such as the cingulate cortex and cerebellum are also involved. Other biological systems including the dopaminergic, oxygen-sensing, opioid, glutamatergic, and serotonergic systems are involved. Further research is needed to determine which of these anatomic locations or biological systems are affected primarily, and which are affected in a secondary response.
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Affiliation(s)
- Brian B Koo
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA; Department of Neurology, Connecticut Veterans Affairs Health System, West Haven, CT, USA; Yale Center for Neuroepidemiology & Clinical Neurological Research, New Haven, CT, USA
| | - Kanika Bagai
- Department of Neurology, Vanderbilt University, Nashville, TN, USA
| | - Arthur S Walters
- Department of Neurology, Vanderbilt University, Nashville, TN, USA
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Lin CC, Fan YM, Lin GY, Yang FC, Cheng CA, Lu KC, Lin JC, Lee JT. 99mTc-TRODAT-1 SPECT as a Potential Neuroimaging Biomarker in Patients With Restless Legs Syndrome. Clin Nucl Med 2016. [PMID: 26204215 DOI: 10.1097/rlu.0000000000000916] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Restless legs syndrome (RLS) is a neurological sensory motor disorder of which pathophysiology remains sketchy. The present study was aimed to determine the diagnostic accuracy and potential of SPECT-TRODAT imaging in discriminating patients with RLS from normal individuals. PATIENTS AND METHODS A total of 34 subjects, 22 diagnosed with RLS and 12 classified as normal, were enrolled. Brain SPECT images were acquired 180 minutes after IV injection of 740 to 925 MBq (20-25 mCi) 99mTc-TRODAT-1 using a double-headed γ-camera equipped with high-resolution fan-beam collimators. Regions of interest were drawn over the whole striatum, caudate, and putamen nucleus of each hemisphere on composite images of the 9 slices with the highest basal ganglia activity. The brain SPECT 99mTc-TRODAT-1 imaging was compared with early-stage RLS patients and healthy volunteers groups. RESULT SPECT imaging in RLS patients showed reduced radioactivity accumulation in the striatum profile. The major abnormal result observed is the significantly reduced uptake in striatal dopamine transporter density and activity. The symmetric striatal uptake was observed, and striatum dopamine transporter destiny was more impaired in patients with RLS disease. SPECT images also showed significant differences between patients and volunteers. CONCLUSIONS This study supports that symptoms of restless legs resulted from the striatum of the brain dopaminergic system dysfunction.
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Affiliation(s)
- Chun-Chieh Lin
- From the *Department of Neurology, Tri-Service General Hospital, National Defense Medical Center, Taipei; †Department of Nuclear Medicine, Cardinal Tien Hospital, New Taipei City; ‡School of Medicine, Fu-Jen Catholic University, Taipei; §Division of Nephrology, Department of Medicine, Cardinal Tien Hospital, New Taipei City; and ∥Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
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Frank MK, de Mello MT, Lee KS, Daubian-Nosé P, Tufik S, Esteves AM. Sleep-related movement disorder symptoms in SHR are attenuated by physical exercise and an angiotensin-converting enzyme inhibitor. Physiol Behav 2016; 154:161-8. [DOI: 10.1016/j.physbeh.2015.11.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 09/28/2015] [Accepted: 11/25/2015] [Indexed: 11/16/2022]
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Abstract
Neuroimaging studies are of crucial relevance in defining the pathophysiology of restless legs syndrome (RLS). MRI studies showed no structural brain lesions and confirmed a central iron deficiency. Structural and functional studies showed an involvement of the thalamus, sensorimotor cortical areas, and cerebellum in RLS and assessed neurotransmission abnormalities in the dopaminergic and opiate systems. Finally, glutamatergic hyperactivity has been proposed as a cause of disrupted and shortened sleep in RLS. Differences among the results of the studies make it difficult to draw any definitive conclusions, thus, suggesting the need for future research.
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Affiliation(s)
- Federica Provini
- Department of Biomedical and Neuromotor Sciences, Bellaria Hospital, University of Bologna, Via Altura 3, Bologna 40139, Italy; IRCCS Institute of Neurological Sciences of Bologna, Bologna, Italy.
| | - Giacomo Chiaro
- Department of Biomedical and Neuromotor Sciences, Bellaria Hospital, University of Bologna, Via Altura 3, Bologna 40139, Italy
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21
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Puligheddu M, Figorilli M, Aricò D, Raggi A, Marrosu F, Ferri R. Time structure of leg movement activity during sleep in untreated Parkinson disease and effects of dopaminergic treatment. Sleep Med 2014; 15:816-24. [DOI: 10.1016/j.sleep.2014.03.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 03/06/2014] [Accepted: 03/10/2014] [Indexed: 11/15/2022]
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The PD-associated alpha-synuclein promoter Rep1 allele 2 shows diminished frequency in restless legs syndrome. Neurogenetics 2014; 15:189-92. [DOI: 10.1007/s10048-014-0407-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 05/15/2014] [Indexed: 11/26/2022]
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23
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Yang JS, Cho YJ, Kang SH, Choi HJ. Demographic and clinical characteristics of patients with restless legs syndrome in spine clinic. J Korean Neurosurg Soc 2014; 55:83-8. [PMID: 24653801 PMCID: PMC3958578 DOI: 10.3340/jkns.2014.55.2.83] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 11/19/2013] [Accepted: 01/10/2014] [Indexed: 01/18/2023] Open
Abstract
Objective The restless legs syndrome (RLS) is a common disorder affecting up to 5% to 15% of the general population, in which the incidence increases with age, and includes paresthesia in the legs. The purpose of this study is to investigate the incidence of RLS in spine center and to review clinical manifestations of this syndrome and its current treatments. Methods Over a period of a year, retrospective medical record review and lumbar magnetic resonance images were performed on 32 patients with RLS in spine clinic who were diagnosed by National Institutes of Health criteria. Affected limbs were classified as five. Two grading systems were used in the evaluation of neural compromises. Results The incidence of RLS was 5.00% (32/639). There were 16 males (50%) and 16 females (50%). The median age at diagnosis was 55.4 years (range, 25-93 years). There are no correlation between the affected limbs of RLS and neural compromises on the lumbar spine. Conclusion The RLS is a clearly common neurologic disorder of the limbs, usually the legs. The awareness of this syndrome can help reduce diagnostic error; thereby, avoiding the morbidity and expense associated with unnecessary studies or inappropriate treatments in RLS patients.
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Affiliation(s)
- Jin Seo Yang
- Department of Neurosurgery, Chuncheon Sacred Heart Hospital, College of Medicine, Hallym University, Chuncheon, Korea
| | - Yong Jun Cho
- Department of Neurosurgery, Chuncheon Sacred Heart Hospital, College of Medicine, Hallym University, Chuncheon, Korea
| | - Suk Hyung Kang
- Department of Neurosurgery, Chuncheon Sacred Heart Hospital, College of Medicine, Hallym University, Chuncheon, Korea
| | - Hyuk Jai Choi
- Department of Neurosurgery, Chuncheon Sacred Heart Hospital, College of Medicine, Hallym University, Chuncheon, Korea
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Abbott SM, Attarian H, Zee PC. Sleep disorders in perinatal women. Best Pract Res Clin Obstet Gynaecol 2014; 28:159-68. [DOI: 10.1016/j.bpobgyn.2013.09.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 07/23/2013] [Accepted: 09/09/2013] [Indexed: 01/20/2023]
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26
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Imaging Brain Functional and Metabolic Changes in Restless Legs Syndrome. Curr Neurol Neurosci Rep 2013; 13:372. [DOI: 10.1007/s11910-013-0372-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Patton SM, Cho YW, Clardy TW, Allen RP, Earley CJ, Connor JR. Proteomic analysis of the cerebrospinal fluid of patients with restless legs syndrome/Willis-Ekbom disease. Fluids Barriers CNS 2013; 10:20. [PMID: 23758918 PMCID: PMC3680184 DOI: 10.1186/2045-8118-10-20] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 05/08/2013] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Restless Legs Syndrome/Willis-Ekbom Disease (RLS/WED) is a sensorimotor disorder that causes patients to experience overwhelming and distressing sensations in the legs compelling the patient to move their legs to provide relief. The purpose of this study was to determine if biomarkers in the cerebrospinal fluid can distinguish RLS/WED patients from neurological controls. METHODS We obtained CSF samples by lumbar puncture from 5 early-onset RLS/WED patients and 5 controls. We performed 2-dimensional difference in-gel electrophoresis (2D-DIGE). Proteins that were significantly altered were identified by Student's t-test. Protein spots that were differentially expressed (p ≤ 0.05, Av. Ratio ≥ 2.0) between RLS/WED and control CSF samples were identified using MALDI-TOF-MS. Statistical analyses of the validation immunoblot assays were performed using Student's t-test. RESULTS In this discovery study we identified 6 candidate CSF protein markers for early-onset RLS/WED. Four proteins (Cystatin C, Lipocalin-type Prostaglandin D2 Synthase, Vitamin D binding Protein, and β-Hemoglobin) were increased and 2 proteins (Apolipoprotein A1 and α-1-acid Glycoprotein) were decreased in RLS/WED patients. CONCLUSIONS Our results reveal a protein profile in the RLS/WED CSF that is consistent with clinical findings of disruptive sleep, cardiovascular dysfunction and painful symptoms. Moreover, protein profiles are consistent with neuropathological findings of activation of hypoxia inducible factor (HIF) pathways and alterations in dopaminergic systems. These data indicate the CSF of RLS/WED patients may provide information relevant to biological basis for RLS/WED, treatment strategies and potential new treatment targets.
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Affiliation(s)
- Stephanie M Patton
- Department of Neurosurgery, Penn State University, Milton S, Hershey Medical Center, 500 University Drive, Hershey, Pennsylvania PA 17033, USA.
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