1
|
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.
Collapse
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
| |
Collapse
|
2
|
Tc-99m TRODAT-1 SPECT is a Potential Biomarker for Restless Leg Syndrome in Patients with End-Stage. J Clin Med 2020; 9:jcm9030889. [PMID: 32213981 PMCID: PMC7141514 DOI: 10.3390/jcm9030889] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 03/19/2020] [Indexed: 12/17/2022] Open
Abstract
Rationales: Restless leg syndrome (RLS) is a common complication in patients with end-stage renal disease (ESRD). However, there is a lack of biomarkers linking uremic RLS to dopaminergic neurons. Previous studies demonstrated that Tc-99m TRODAT-1 SPECT was a biomarker for RLS but the correlation between the physiologic parameter was lacking. Methods: Overall, 32 patients were enrolled in the study and divided into the following 3 groups: (1) control (n = 13), (2) ESRD without RLS (n = 8) and (3) ESRD with RLS (n = 11). All patients had a clinical diagnosis of RLS and received Tc-99m TRODAT-1 SPECT. A subgroup analysis was performed to compare differences between the control and ESRD with RLS groups. Tc-99m TRODAT-1 SPECT was performed and activities in the striatum and occipital areas were measured using manually delineated regions of interest (ROIs) by an experienced nuclear medicine radiologist who was blinded to clinical data. Results: The total ratio of Tc-99m TRODAT SPECT was lower in the ESRD with RLS group (p = 0.046). The uptake ratio of TRODAT negatively correlated with serum parathyroid hormone (r = −0.577, p = 0.015) and ferritin (r = −0.464, p = 0.039) concentrations. However, the uptake positively correlated with the hemoglobin concentration (r = 0.531, p = 0.011). The sensitivity and specificity of the total TRODAT ratio for predicting RLS in the overall population were 95.0% and 67.7%, respectively, at a cutoff value of 0.980 (area under the curve of receiver operating characteristic curve was 0.767, p = 0.024). Conclusion: In patients with ESRD and RLS, Tc-99m TRODAT might be a potential biomarker. Dysregulated hemoglobin, serum parathyroid hormone and serum ferritin concentrations might influence the uptake of the TRODAT ratio.
Collapse
|
3
|
Sun Y, Liu C, Chen Z, Li B, Lv Z, Wang J, Lou J, Tang J, Wang Y, Zhang G, Liu X. A phase 2, open-label, multi-center study to evaluate the efficacy and safety of 99mTc-TRODAT-1 SPECT to detect Parkinson’s disease. Ann Nucl Med 2019; 34:31-37. [DOI: 10.1007/s12149-019-01412-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 10/07/2019] [Indexed: 11/29/2022]
|
4
|
Casoni F, Galbiati A, Ferini-Strambi L. D3 receptor agonist efficacy in restless legs syndrome. PHARMACOLOGY OF RESTLESS LEGS SYNDROME (RLS) 2019; 84:21-35. [DOI: 10.1016/bs.apha.2019.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
5
|
Zhu L, Li J, Ren C, Zhang M, Xue M, Yu C, Zhang W. Clinical Study of Restless Leg Syndrome Accompanied by Psychological Symptoms Induced by High-Dose Treatment With Madopar. Front Psychiatry 2019; 10:360. [PMID: 31178769 PMCID: PMC6544116 DOI: 10.3389/fpsyt.2019.00360] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 05/08/2019] [Indexed: 11/13/2022] Open
Abstract
Objectives: Some neurological disorders demonstrate indistinguishable psychological symptoms at an early stage, especially when accompanied by jitters similar to those in Parkinson's disease. During dopamine replacement therapy, some patients display restless leg syndrome (RLS)-like symptoms. Therefore, we aimed to analyze treatment strategies and the prognosis of RLS caused by high-dose Madopar. Methods: Nine patients who were misdiagnosed with Parkinson's disease, taking a high dose of Madopar, and showed symptoms of anxiety, depression, and somatization were recruited. Clinical data were collected, and strategies of treatment and prognosis were analyzed. Results: Seven patients demonstrated varying degrees of anxiety and depression, and the other two cases were misdiagnosed as Parkinson's disease. During Madopar treatment, patients gradually showed aggravated symptoms, including swelling, numbness, pain, and other sensory abnormalities in both lower extremities, which spread to both upper extremities in a few patients. Among the seven patients, symptoms of anxiety, depression, insomnia, and somatization significantly worsened during the observation period. The average time from taking Madopar to the appearance of RLS was 2.6 ± 0.6 months, the average time to clinical diagnosis was 18.17 ± 9.40 months, and the average dosage of Madopar was 1.44 ± 0.21 g per day. Gradually reducing the Madopar dosage and administering a small dose of long-acting dopamine preparation greatly alleviated the symptoms after 3 months. Conclusion: A high dose of Madopar can cause RLS-like symptoms accompanied by anxiety, depression, insomnia, and other mental health symptoms. These symptoms should be more closely monitored by clinicians.
Collapse
Affiliation(s)
- Lei Zhu
- Department of Neurology, The First People's Hospital of Huainan, The First Affiliated Hospital of Anhui University of Science and Technology, Huainan, China
| | - Jing Li
- Department of Neurology, The First People's Hospital of Huainan, The First Affiliated Hospital of Anhui University of Science and Technology, Huainan, China
| | - Chongyang Ren
- Department of Neurology, The First People's Hospital of Huainan, The First Affiliated Hospital of Anhui University of Science and Technology, Huainan, China
| | - Mei Zhang
- Department of Neurology, The First People's Hospital of Huainan, The First Affiliated Hospital of Anhui University of Science and Technology, Huainan, China
| | - Min Xue
- Department of Neurology, The First People's Hospital of Huainan, The First Affiliated Hospital of Anhui University of Science and Technology, Huainan, China
| | - Chuanqing Yu
- Department of Neurology, The First People's Hospital of Huainan, The First Affiliated Hospital of Anhui University of Science and Technology, Huainan, China
| | - Weili Zhang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Capital Medical University, Beijing, China
| |
Collapse
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
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.
Collapse
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
| |
Collapse
|
8
|
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]
|
9
|
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.
Collapse
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.
| |
Collapse
|
10
|
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.
Collapse
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
| |
Collapse
|
11
|
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.
Collapse
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.
| |
Collapse
|