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Misawa H, Kamishima K, Koyama T, Ohgaki L, Morisaki Y, Yamanaka T, Itohara S, Sawano S, Mizunoya W, Ogihara N. Type selective ablation of postnatal slow and fast fatigue-resistant motor neurons in mice induces late onset kinetic and postural tremor following fiber-type transition and myopathy. Exp Neurol 2024; 376:114772. [PMID: 38599366 DOI: 10.1016/j.expneurol.2024.114772] [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] [Received: 09/19/2023] [Revised: 03/28/2024] [Accepted: 04/06/2024] [Indexed: 04/12/2024]
Abstract
Animals on Earth need to hold postures and execute a series of movements under gravity and atmospheric pressure. VAChT-Cre is a transgenic Cre driver mouse line that expresses Cre recombinase selectively in motor neurons of S-type (slow-twitch fatigue-resistant) and FR-type (fast-twitch fatigue-resistant). Sequential motor unit recruitment is a fundamental principle for fine and smooth locomotion; smaller-diameter motor neurons (S-type, FR-type) first contract low-intensity oxidative type I and type IIa muscle fibers, and thereafter larger-diameter motor neurons (FInt-type, FF-type) are recruited to contract high-intensity glycolytic type IIx and type IIb muscle fibers. To selectively eliminate S- and FR-type motor neurons, VAChT-Cre mice were crossbred with NSE-DTA mice in which the cytotoxic diphtheria toxin A fragment (DTA) was expressed in Cre-expressing neurons. The VAChT-Cre;NSE-DTA mice were born normally but progressively manifested various characteristics, including body weight loss, kyphosis, kinetic and postural tremor, and muscular atrophy. The progressive kinetic and postural tremor was remarkable from around 20 weeks of age and aggravated. Muscular atrophy was apparent in slow muscles, but not in fast muscles. The increase in motor unit number estimation was detected by electromyography, reflecting compensatory re-innervation by remaining FInt- and FF-type motor neurons to the orphaned slow muscle fibers. The muscle fibers gradually manifested fast/slow hybrid phenotypes, and the remaining FInt-and FF-type motor neurons gradually disappeared. These results suggest selective ablation of S- and FR-type motor neurons induces progressive muscle fiber-type transition, exhaustion of remaining FInt- and FF-type motor neurons, and late-onset kinetic and postural tremor in mice.
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Affiliation(s)
- Hidemi Misawa
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Minato-ku, Tokyo, Japan.
| | - Kai Kamishima
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Minato-ku, Tokyo, Japan
| | - Tenkei Koyama
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Minato-ku, Tokyo, Japan
| | - Lisa Ohgaki
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Minato-ku, Tokyo, Japan
| | - Yuta Morisaki
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Minato-ku, Tokyo, Japan
| | - Tomoyuki Yamanaka
- Department of Neuroscience of Disease, Brain Research Institute, Niigata University, Chuo-ku, Niigata, Japan
| | - Shigeyoshi Itohara
- Laboratory for Behavioral Genetics, RIKEN Brain Science Institute, Wako, Saitama, Japan
| | - Shoko Sawano
- Department of Food and Life Science, School of Life and Environmental Science, Azabu University, Sagamihara, Kanagawa, Japan
| | - Wataru Mizunoya
- Department of Animal Science and Biotechnology, School of Veterinary Medicine, Azabu University, Sagamihara, Kanagawa, Japan
| | - Naomichi Ogihara
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
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Matthews LG, Puryear CB, Correia SS, Srinivasan S, Belfort GM, Pan MK, Kuo SH. T-type calcium channels as therapeutic targets in essential tremor and Parkinson's disease. Ann Clin Transl Neurol 2023; 10:462-483. [PMID: 36738196 PMCID: PMC10109288 DOI: 10.1002/acn3.51735] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 12/20/2022] [Accepted: 12/21/2022] [Indexed: 02/05/2023] Open
Abstract
Neuronal action potential firing patterns are key components of healthy brain function. Importantly, restoring dysregulated neuronal firing patterns has the potential to be a promising strategy in the development of novel therapeutics for disorders of the central nervous system. Here, we review the pathophysiology of essential tremor and Parkinson's disease, the two most common movement disorders, with a focus on mechanisms underlying the genesis of abnormal firing patterns in the implicated neural circuits. Aberrant burst firing of neurons in the cerebello-thalamo-cortical and basal ganglia-thalamo-cortical circuits contribute to the clinical symptoms of essential tremor and Parkinson's disease, respectively, and T-type calcium channels play a key role in regulating this activity in both the disorders. Accordingly, modulating T-type calcium channel activity has received attention as a potentially promising therapeutic approach to normalize abnormal burst firing in these diseases. In this review, we explore the evidence supporting the theory that T-type calcium channel blockers can ameliorate the pathophysiologic mechanisms underlying essential tremor and Parkinson's disease, furthering the case for clinical investigation of these compounds. We conclude with key considerations for future investigational efforts, providing a critical framework for the development of much needed agents capable of targeting the dysfunctional circuitry underlying movement disorders such as essential tremor, Parkinson's disease, and beyond.
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Affiliation(s)
| | - Corey B Puryear
- Praxis Precision Medicines, Boston, Massachusetts, 02110, USA
| | | | - Sharan Srinivasan
- Praxis Precision Medicines, Boston, Massachusetts, 02110, USA.,Department of Neurology, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | | | - Ming-Kai Pan
- Department and Graduate Institute of Pharmacology, National Taiwan University College of Medicine, Taipei, 10051, Taiwan.,Neurobiology and Cognitive Science Center, National Taiwan University, Taipei, 10617, Taiwan.,Department of Medical Research, National Taiwan University Hospital, Taipei, 10002, Taiwan.,Cerebellar Research Center, National Taiwan University Hospital, Yun-Lin Branch, Yun-Lin, 64041, Taiwan
| | - Sheng-Han Kuo
- Department of Neurology, Columbia University, New York, New York, 10032, USA.,Initiative for Columbia Ataxia and Tremor, Columbia University, New York, New York, 10032, USA
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Lee J, Kim J, Cortez J, Chang SY. Thalamo-cortical network is associated with harmaline-induced tremor in rodent model. Exp Neurol 2022; 358:114210. [PMID: 36007599 DOI: 10.1016/j.expneurol.2022.114210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 08/19/2022] [Indexed: 11/04/2022]
Abstract
Essential tremor (ET) is the most frequent form of pathologic tremor and one of the most common adult-onset neurologic impairments. However, underlying mechanisms by which structural alterations within the tremor circuit generate the pathological state and how rhythmic neuronal activities propagate and drive tremor remains unclear. Harmaline (HA)-induced tremor model has been most frequently utilized animal model for ET studies, however, there is still a dearth of knowledge over the degree to whether HA-induced tremor mimics the actual underlying pathophysiology of ET, particularly the involvement of thalamo-cortical region. In this study, we investigated the electrophysiological response of the motor circuit including the ventrolateral thalamus (vlTh) and the primary motor cortex (M1), and the modulatory effect of thalamic deep brain stimulation (DBS) using a rat HA-induced tremor model. We found that the theta and high-frequency oscillation (HFO) band power significantly increased after HA administration in both vlTh and M1, and the activity was modulated by the tremor suppression drug (propranolol) and the thalamic DBS. The theta band phase synchronization between the vlTh and M1 was significantly enhanced during the HA-induced tremor, and the transition of cross-frequency coupling in vlTh was found to be associated with the state of HA-induced tremor. Our findings support that the HA tremor could be useful as a valid preclinical model of ET in the context of thalamo-cortical neural network interaction.
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Affiliation(s)
- Jeyeon Lee
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - Jiwon Kim
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Joshua Cortez
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Su-Youne Chang
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA.
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Quantitative behavioral models for high-resolution measurement and characterization of tremor in rodents. Brain Res Bull 2022; 186:8-15. [PMID: 35487386 DOI: 10.1016/j.brainresbull.2022.04.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 04/16/2022] [Accepted: 04/20/2022] [Indexed: 01/25/2023]
Abstract
Tremor is an involuntary, rhythmic movement disorder. Despite its prevalence, the underlying pathophysiology remains poorly understood and effective treatment options are limited. Animal models are essential in enhancing our understanding of the mechanisms of tremorogenesis and developing new therapeutic interventions. Although tremor is amenable to measurement by automated systems, visual observation is still the most prevalent method for recording tremor in animal studies. This review gives a brief summary of two behavioral methods that enable quantitative measurement of forelimb tremor (the press-while-licking task) and whole-body tremor (the force-plate actometer) in rodents. These methods utilize force transducer and computing technologies to generate high-resolution force-time waveforms for automated detection and characterization of tremor. The focus will be on the sensitive, precise, and quantitative measurement of tremors induced in rodents by low-dose pharmacological agents, brain lesion, physical training, and genetic mutations. The methods reviewed here provide new tools that can facilitate preclinical assessment of treatment strategies for tremor.
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Kosmowska B, Wardas J. The Pathophysiology and Treatment of Essential Tremor: The Role of Adenosine and Dopamine Receptors in Animal Models. Biomolecules 2021; 11:1813. [PMID: 34944457 PMCID: PMC8698799 DOI: 10.3390/biom11121813] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/25/2021] [Accepted: 11/30/2021] [Indexed: 12/13/2022] Open
Abstract
Essential tremor (ET) is one of the most common neurological disorders that often affects people in the prime of their lives, leading to a significant reduction in their quality of life, gradually making them unable to independently perform the simplest activities. Here we show that current ET pharmacotherapy often does not sufficiently alleviate disease symptoms and is completely ineffective in more than 30% of patients. At present, deep brain stimulation of the motor thalamus is the most effective ET treatment. However, like any brain surgery, it can cause many undesirable side effects; thus, it is only performed in patients with an advanced disease who are not responsive to drugs. Therefore, it seems extremely important to look for new strategies for treating ET. The purpose of this review is to summarize the current knowledge on the pathomechanism of ET based on studies in animal models of the disease, as well as to present and discuss the results of research available to date on various substances affecting dopamine (mainly D3) or adenosine A1 receptors, which, due to their ability to modulate harmaline-induced tremor, may provide the basis for the development of new potential therapies for ET in the future.
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Affiliation(s)
| | - Jadwiga Wardas
- Department of Neuropsychopharmacology, Maj Institute of Pharmacology Polish Academy of Sciences, 31-343 Kraków, Poland;
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Batra D, Kamble N, Bhattacharya A, Sahoo L, Yadav R, Pal PK. Modulatory effect of continuous theta burst stimulation in patients with essential tremor. Parkinsonism Relat Disord 2021; 94:62-66. [PMID: 34890877 DOI: 10.1016/j.parkreldis.2021.11.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 11/20/2021] [Accepted: 11/23/2021] [Indexed: 10/19/2022]
Abstract
INTRODUCTION We aimed to study the cortical and intracortical functions in patients of ET using transcranial magnetic stimulation (TMS) and to evaluate the effect of continuous theta burst stimulation (cTBS) on the tremor characteristics. METHODS Ten ET and 20 healthy controls were included in the study. All the participants were evaluated with TMS with recording of resting motor threshold (RMT), central motor conduction time, contralateral silent period (cSP), short interval intracortical inhibition (SICI) and intracortical facilitation (ICF). Subsequently only ET patients underwent cTBS of the motor cortex (M1) followed by repeat TMS. RESULTS The mean age of the patients (46.5 ± 17.2 years) was comparable to healthy controls (55.4 ± 9.2 years; p = 0.16). There was a non-significant increase in RMT in ET patients (44 ± 12.5%) when compared to healthy controls (40.9 ± 6.9%; p = 0.48). There was a significant reduction of cSP in the ET group (102.03 ± 15.26 msec) compared to healthy controls (116.1 ± 15.2, p = 0.03). In addition, a significant reduction in ICF was observed in ET patients (0.9 ± 0.7) compared to healthy controls (1.8 ± 0.8, p = 0.01). Following cTBS there was a significant reduction in the tremor scores [FTMRS (Pre-cTBS: 29.3 ± 18.7, Post-cTBS: 25.3 ± 16.8; p < 0.001) and TETRAS (pre-cTBS: 34.4 ± 16.2, post-cTBS: 29.8 ± 12.1; p = 0.01)] and improvement (increase) of the duration of cSP (pre-cTBS: 102.03 ± 15.3 msec., post-cTBS: 119.4 ± 12.03 msec; p = 0.05). CONCLUSIONS Patients with ET have GABAergic and glutaminergic dysfunction as demonstrated by reduced cSP and ICF. However, only the cSP improved following cTBS of M1 region, with a corresponding improvement of tremor severity suggesting the effect of cTBS on the cerebello-thalamo-cortical network.
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Affiliation(s)
- Dhruv Batra
- Department of Neurology, National Institute of Mental Health & Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, Karnataka, India
| | - Nitish Kamble
- Department of Neurology, National Institute of Mental Health & Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, Karnataka, India
| | - Amitabh Bhattacharya
- Department of Neurology, National Institute of Mental Health & Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, Karnataka, India
| | - Lulup Sahoo
- Department of Neurology, National Institute of Mental Health & Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, Karnataka, India
| | - Ravi Yadav
- Department of Neurology, National Institute of Mental Health & Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, Karnataka, India
| | - Pramod Kumar Pal
- Department of Neurology, National Institute of Mental Health & Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, Karnataka, India.
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Bello EM, Blumenfeld M, Dao J, Krieg JDS, Wilmerding LK, Johnson MD. Considerations Using Harmaline for a Primate Model of Tremor. Tremor Other Hyperkinet Mov (N Y) 2021; 11:35. [PMID: 34611499 PMCID: PMC8447964 DOI: 10.5334/tohm.634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 08/25/2021] [Indexed: 11/20/2022] Open
Abstract
Background While harmaline has been used as a pharmacological model of essential tremor (ET) in rodents and pigs, less is known about the effects of this pharmacological treatment in awake-behaving non-human primates. In this study, we investigated the time-course, amplitude, frequency, and consistency of harmaline tremor in primates. Methods Three rhesus macaques were administered doses of harmaline ranging from 2-12 mg/kg (i.m.), and tremorous movements were quantified with accelerometers. One subject was also trained to perform a self-paced cued reaching task, with task engagement assessed under harmaline doses ranging from 2-8 mg/kg (i.m.). Results Whole-body tremors manifested within 30 minutes of threshold-dose administration, and peak oscillatory frequency ranged between 10-14 Hz. However, large differences in tremor intensity and intermittency were observed across individual subjects under similar dosing levels. Additionally, engagement with the reaching task was dependent on harmaline dose, with performance mostly unaffected at 2 mg/kg and with little task-engagement at 8 mg/kg. Discussion We provide a detailed assessment of factors that may underlie the heterogeneous responses to harmaline, and lay out important caveats towards the applicability of the behaving harmaline-tremoring non-human primate as a preclinical model for ET. Highlights The harmaline-primate is revisited for its potential as a preclinical model of tremor. Spontaneous tremor was heterogenous in amplitude across subjects despite similar harmaline doses, action tremors were not consistently observed, and performance on a behavioral task degraded with higher dosages.
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Affiliation(s)
- Edward M. Bello
- Biomedical Engineering Department, University of Minnesota, US
| | | | - Joan Dao
- Biomedical Engineering Department, University of Minnesota, US
| | | | | | - Matthew D. Johnson
- Biomedical Engineering Department, University of Minnesota, US
- Institute for Translational Neuroscience, University of Minnesota, US
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Abstract
PURPOSE OF REVIEW Tremor is a common neurological symptom with a plethora of potential etiologies. Apart from physiological tremor, the vast majority of tremor syndromes are linked to a pacemaker in the central nervous system (CNS) or, less common, in the peripheral nervous system. Myogenic tremor is a novel tremor entity, first reported in 2019 and believed to originate in the muscle itself. In this review, we describe the clinical properties of myogenic tremor and discuss its presumed pathogenesis on the basis of all of the patient cases published so far. RECENT FINDINGS Myogenic tremor manifests itself as a high frequency, postural, and kinetic tremor with onset in infancy. To date, only myopathies affecting the contractile elements, in particular myosin and a myosin-associated protein, have been recognized to feature myogenic tremor. The generator of the tremor is believed to be located in the sarcomere, with propagation and amplification of sarcomeric oscillatory activity through CNS reflex loops, similar to neuropathic tremor. SUMMARY True myogenic tremor must be distinguished from centrally mediated tremor due to myopathies with central nervous system involvement, i.e., mitochondrial myopathies or myotonic dystrophies. The presence of myogenic tremor strongly points toward a sarcomere-associated mutation and may thus be a valuable clinical tool for the differential diagnosis of myopathies.
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Objective detection of microtremors in netrin-G2 knockout mice. J Neurosci Methods 2021; 351:109074. [PMID: 33450333 DOI: 10.1016/j.jneumeth.2021.109074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 01/04/2021] [Accepted: 01/07/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND Essential tremor is the most prevalent movement disorder and is thought to be caused by abnormalities in the cerebellar system; however, its underlying neural mechanism is poorly understood. In this study, we found that mice lacking netrin-G2, a cell adhesion molecule which is expressed in neural circuits related to the cerebellar system, exhibited a microtremor resembling an essential tremor. However, it was difficult to quantify microtremors in netrin-G2 KO mice. NEW METHOD We developed a new tremor detector which can quantify the intensity and frequency of a tremor. RESULTS Using this system, we were able to characterize both the microtremors in netrin-G2 KO mice and low-dose harmaline-induced tremors which, to date, had been difficult to detect. Alcohol and anti-tremor drugs, which are effective in decreasing the symptoms of essential tremor in patients, were examined in netrin-G2 KO mice. We found that some drugs lowered the tremor frequency, but had little effect on tremor intensity. Forced swim as a stress stimulus in netrin-G2 KO mice dramatically enhanced tremor symptoms. COMPARISON WITH EXISTING METHODS The detection performance even for tremors induced by low-dose harmaline was similar to that in previous studies or more sensitive than the others. CONCLUSIONS Microtremors in netrin-G2 KO mice are reliably and quantitatively detected by our new tremor detection system. We found different effects of medicines and factors between human essential tremors and microtremors in netrin-G2 KO mice, suggesting that the causations, mechanisms, and symptoms of tremors vary and are heterogeneous, and the objective analyses are required.
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Wang Y, Wang H, Zhang L, Zhang Y, Deng G, Li S, Cao N, Guan H, Cheng X, Wang C. Potential mechanisms of tremor tolerance induced in rats by the repeated administration of total alkaloid extracts from the seeds of Peganum harmala Linn. JOURNAL OF ETHNOPHARMACOLOGY 2020; 262:113183. [PMID: 32730891 DOI: 10.1016/j.jep.2020.113183] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 06/14/2020] [Accepted: 07/12/2020] [Indexed: 06/11/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The seeds of Peganum harmala Linn have been widely used for the treatment of nervous, cardiovascular, gastrointestinal, respiratory, and endocrine diseases and many other human ailments. However, tremor toxicity occurs after overdose and is tolerated following multiple dosing. Thus far, little is known about the underlying mechanisms of tremors and tremor tolerance. AIM OF THE STUDY To investigate the potential mechanisms of tremors and tremor tolerance induced in rats by the repeated administration of total alkaloid extracts from the seeds of P. harmala (TAEP). MATERIALS AND METHODS A tremor model was induced in male Wistar rats by administering TAEP at a dose of 150 mg/kg/day. To evaluate tremor action, behavioral assessment was conducted by using a custom-built tremor acquisition and analysis system. To investigate the relationships between tremors and neurotransmitter levels in the brain, various neurotransmitters were simultaneously quantified by an ultra-performance liquid chromatography combined with electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) system, and the association between these two parameters was analyzed using Pearson correlation coefficients. To further elucidate the potential mechanisms of the alterations of neurotransmitter levels in cortical tissues, the protein expression levels of several important enzymes and transporters that are closely related to neurotransmitter levels were investigated. In addition, neuropathological analysis was conducted to assess the effect of TAEP on neurons in the brain. To further clarify the potential mechanisms of TAEP-induced neurodegeneration in the brain, c-fos was subjected to immunohistochemical analysis, and oxidative stress markers were examined. RESULTS Tremors initially occurred in rats after the oral administration of TAEP at a dose of 150 mg/kg/day. However, they were tolerated following repeated dosing. The levels of 5-hydroxytryptamine (5-HT) and glycine (Gly) in cortical tissues were most likely associated with the tremor response. Tremor tolerance also likely resulted from the degeneration of cerebellar Purkinje cells. Furthermore, the alteration of 5-HT levels was mainly attributed to the downregulated expression of monoamine oxidase A (MAO-A). The degeneration of Purkinje neurons might have resulted from the overexpression of c-fos and increased oxidative stress in the cerebellum after the multiple dosing of TAEP. CONCLUSION The tremor response induced by TAEP at high doses is closely related to the concentrations of 5-HT and Gly in cortical tissues. Tremor tolerance may also be attributed to the degeneration of cerebellar Purkinje cells after the repeated dosing of TAEP. Further studies should be conducted to elucidate the interaction of the alkaloids on the neurotransmitter receptors, the expression of related neurotransmitter receptors, the specific signaling pathway involved in regulating MAO-A, and the mechanism of the loss and functional recovery of cerebellar Purkinje neurons.
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Affiliation(s)
- Youxu Wang
- Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, The MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Centre for Standardization of Chinese Medicines, 1200 Cailun Road, Shanghai, 201203, China
| | - Hanxue Wang
- Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, The MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Centre for Standardization of Chinese Medicines, 1200 Cailun Road, Shanghai, 201203, China; Shanghai TCM-integrated Hospital, Shanghai University of Traditional Chinese Medicine, 230 Baoding Road, Shanghai, 200082, China
| | - Liuhong Zhang
- Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, The MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Centre for Standardization of Chinese Medicines, 1200 Cailun Road, Shanghai, 201203, China
| | - Yunpeng Zhang
- Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, The MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Centre for Standardization of Chinese Medicines, 1200 Cailun Road, Shanghai, 201203, China
| | - Gang Deng
- Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, The MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Centre for Standardization of Chinese Medicines, 1200 Cailun Road, Shanghai, 201203, China
| | - Shuping Li
- Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, The MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Centre for Standardization of Chinese Medicines, 1200 Cailun Road, Shanghai, 201203, China
| | - Ning Cao
- Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, The MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Centre for Standardization of Chinese Medicines, 1200 Cailun Road, Shanghai, 201203, China
| | - Huida Guan
- Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, The MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Centre for Standardization of Chinese Medicines, 1200 Cailun Road, Shanghai, 201203, China
| | - Xuemei Cheng
- Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, The MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Centre for Standardization of Chinese Medicines, 1200 Cailun Road, Shanghai, 201203, China
| | - Changhong Wang
- Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, The MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Centre for Standardization of Chinese Medicines, 1200 Cailun Road, Shanghai, 201203, China.
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Stocco MR, Tolledo C, Wadji FB, Gonzalez FJ, Miksys S, Tyndale RF. Human CYP2D6 in the Brain Is Protective Against Harmine-Induced Neurotoxicity: Evidence from Humanized CYP2D6 Transgenic Mice. Mol Neurobiol 2020; 57:4608-4621. [PMID: 32761352 PMCID: PMC8865091 DOI: 10.1007/s12035-020-02050-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 07/28/2020] [Indexed: 10/25/2022]
Abstract
CYP2D6 metabolically inactivates several neurotoxins, including beta-carbolines, which are implicated in neurodegenerative diseases. Variation in CYP2D6 within the brain may alter local inactivation of neurotoxic beta-carbolines, thereby influencing neurotoxicity. The beta-carboline harmine, which induces hypothermia and tremor, is metabolized by CYP2D6 to the non-hypothermic/non-tremorgenic harmol. Transgenic mice (TG), expressing human CYP2D6 in addition to their endogenous mouse CYP2D, experience less harmine-induced hypothermia and tremor compared with wild-type mice (WT). We first sought to elucidate the role of CYP2D in general within the brain in harmine-induced hypothermia and tremor severity. A 4-h intracerebroventricular (ICV) pretreatment with the CYP2D inhibitor propranolol increased harmine-induced hypothermia and tremor in TG and increased harmine-induced hypothermia in WT. We next sought to specifically demonstrate that human CYP2D6 expressed in TG brain altered harmine response severity. A 24-h ICV propranolol pretreatment, which selectively and irreversibly inhibits human CYP2D6 in TG brain, increased harmine-induced hypothermia. This 24-h pretreatment had no impact on harmine response in WT, as propranolol is not an irreversible inhibitor of mouse CYP2D in the brain, thus confirming no off-target effects of ICV propranolol pretreatment. Human CYP2D6 activity in TG brain was sufficient in vivo to mitigate harmine-induced neurotoxicity. These findings suggest that human CYP2D6 in the brain is protective against beta-carboline-induced neurotoxicity and that the extensive interindividual variability in CYP2D6 expression in human brain may contribute to variation in susceptibility to certain neurotoxin-associated neurodegenerative disorders.
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Affiliation(s)
- Marlaina R Stocco
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Cole Tolledo
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Fariba Baghai Wadji
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Frank J Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Sharon Miksys
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Rachel F Tyndale
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada.
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada.
- Department of Psychiatry, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
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12
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Abstract
Tremor and myoclonus are two common hyperkinetic movement disorders. Tremor is characterized by rhythmic oscillatory movements while myoclonic jerks are usually arrhythmic. Tremor can be classified into subtypes including the most common types: essential, enhanced physiological, and parkinsonian tremor. Myoclonus classification is based on its anatomic origin: cortical, subcortical, spinal, and peripheral myoclonus. The clinical presentations are unfortunately not always classic and electrophysiologic investigations can be helpful in making a phenotypic diagnosis. Video-polymyography is the main technique to (sub)classify the involuntary movements. In myoclonus, advanced electrophysiologic testing, such as back-averaging, coherence analysis, somatosensory-evoked potentials, and the C-reflex can be of additional value. Recent developments in tremor point toward a role for intermuscular coherence analysis to differentiate between tremor subtypes. Classification of the movement disorder based on clinical and electrophysiologic features is important, as it enables the search for an etiological diagnosis and guides tailored treatment.
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Affiliation(s)
- R Zutt
- Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands
| | - J W Elting
- Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands
| | - M A J Tijssen
- Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands.
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13
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Lee J, Chang SY. Altered Primary Motor Cortex Neuronal Activity in a Rat Model of Harmaline-Induced Tremor During Thalamic Deep Brain Stimulation. Front Cell Neurosci 2019; 13:448. [PMID: 31680866 PMCID: PMC6803555 DOI: 10.3389/fncel.2019.00448] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 09/19/2019] [Indexed: 01/30/2023] Open
Abstract
Although deep brain stimulation (DBS) is a clinically effective surgical treatment for essential tremor (ET), and its neurophysiological mechanisms are not fully understood. As the motor thalamus is the most popular DBS target for ET, and it is known that the thalamic nucleus plays a key role in relaying information about the external environment to the cerebral cortex, it is important to investigate mechanisms of thalamic DBS in the context of the cerebello-thalamo-cortical neuronal network. To examine this, we measured single-unit neuronal activities in the resting state in M1 during VL thalamic DBS in harmaline-induced tremor rats and analyzed neuronal activity patterns in the thalamo-cortical circuit. Four activity patterns - including oscillatory burst, oscillatory non-burst, irregular burst, and irregular non-burst - were identified by harmaline administration; and those firing patterns were differentially affected by VL thalamic DBS, which seems to drive pathologic cortical signals to signals in normal status. As specific neuronal firing patterns like oscillation or burst are considered important for information processing, our results suggest that VL thalamic DBS may modify pathophysiologic relay information rather than simply inhibit the information transmission.
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Affiliation(s)
- Jihyun Lee
- Laboratory of Brain & Cognitive Sciences for Convergence Medicine, College of Medicine, Hallym University, Anyang, South Korea
| | - Su-Youne Chang
- Department of Neurologic Surgery, Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
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14
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Lee J, Jo HJ, Kim I, Lee J, Min HK, In MH, Knight EJ, Chang SY. Mapping BOLD Activation by Pharmacologically Evoked Tremor in Swine. Front Neurosci 2019; 13:985. [PMID: 31619955 PMCID: PMC6759958 DOI: 10.3389/fnins.2019.00985] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 09/02/2019] [Indexed: 11/26/2022] Open
Abstract
Harmaline-induced tremor is one of the most commonly utilized disease models for essential tremor (ET). However, the underlying neural networks involved in harmaline-induced tremor and the degree to which these are a representative model of the pathophysiologic mechanism of ET are incompletely understood. In this study, we evaluated the functional brain network effects induced by systemic injection of harmaline using pharmacological functional magnetic resonance imaging (ph-fMRI) in the swine model. With harmaline administration, we observed significant activation changes in cerebellum, thalamus, and inferior olivary nucleus (ION). In addition, inter-regional correlations in activity between cerebellum and deep cerebellar nuclei and between cerebellum and thalamus were significantly enhanced. These harmaline-induced effects gradually decreased with repeated administration of drug, replicating the previously demonstrated ‘tolerance’ effect. This study demonstrates that harmaline-induced tremor is associated with activity changes in brain regions previously implicated in humans with ET. Thus, harmaline-induction of tremor in the swine may be a useful model to explore the neurological effects of novel therapeutic agents and/or neuromodulation techniques for ET.
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Affiliation(s)
- Jeyeon Lee
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States
| | - Hang Joon Jo
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States.,Department of Radiology, Mayo Clinic, Rochester, MN, United States.,Department of Neurology, Mayo Clinic, Rochester, MN, United States.,Department of Physiology, College of Medicine, Hanyang University, Seoul, South Korea
| | - Inyong Kim
- Department of Neurology, Mayo Clinic, Rochester, MN, United States
| | - Jihyun Lee
- Laboratory of Brain and Cognitive Sciences for Convergence Medicine, Hallym University College of Medicine, Anyang, South Korea
| | - Hoon-Ki Min
- Department of Radiology, Mayo Clinic, Rochester, MN, United States
| | - Myung-Ho In
- Department of Radiology, Mayo Clinic, Rochester, MN, United States
| | - Emily J Knight
- Department of Developmental Behavioral Pediatrics, University of Rochester, Rochester, NY, United States
| | - Su-Youne Chang
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States.,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
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15
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León Ruiz M, Benito-León J. The Top 50 Most-Cited Articles in Orthostatic Tremor: A Bibliometric Review. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2019; 9:tre-09-679. [PMID: 31413901 PMCID: PMC6691913 DOI: 10.7916/tohm.v0.679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 07/06/2019] [Indexed: 12/20/2022]
Abstract
Background Article-level citation count is a hallmark indicating scientific impact. We aimed to pinpoint and evaluate the top 50 most-cited articles in orthostatic tremor (OT). Methods The ISI Web of Knowledge database and 2017 Journal Citation Report Science Edition were used to retrieve the 50 top-cited OT articles published from 1984 to April 2019. Information was collected by the Analyze Tool on the Web of Science, including number of citations, publication title, journal name, publication year, and country and institution of origin. Supplementary analyses were undertaken to clarify authorship, study design, level of evidence, and category. Results Up to 66% of manuscripts were recovered from five journals: Movement Disorders (n = 18), Brain (n = 4), Journal of Clinical Neurophysiology (n = 4), Neurology (n = 4), and Clinical Neurophysiology (n = 3). Articles were published between 1984 and 2018, with expert opinion as the predominant design (n = 22) and review as category (n = 17). Most articles had level 5 evidence (n = 26). According to their countries of origin, 34% of articles belonged to the United States (n = 17) leading the list, followed by United Kingdom (n = 15). University College London yielded the greater number of articles (n = 12), followed by the University of Kiel (n = 9). Most popular authors were G. Deuschl (n = 10), C.D. Marsden (n = 6), J. Jankovic (n = 5), P.D. Thompson (n = 5), J.C. Rothwell (n = 5), L.J. Findley (n = 4), and P. Brown (n = 4), who together accounted for 48% of them. All papers were in English. Discussion Publishing high-cited OT articles could be facilitated by source journal, study design, category, publication language, and country and institution of origin.
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Affiliation(s)
| | - Julián Benito-León
- Department of Neurology, Hospital Universitario 12 de Octubre, Madrid, ES.,Department of Medicine, Faculty of Medicine, Universidad Complutense de Madrid, Madrid, ES.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, ES
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16
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Mohammadi F, Abedini Esfahlani M, Shabani M. Erythropoietin ameliorates harmaline-induced essential tremor and cognition disturbances. Neurosci Lett 2019; 704:153-158. [PMID: 30974232 DOI: 10.1016/j.neulet.2019.04.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 03/22/2019] [Accepted: 04/08/2019] [Indexed: 01/12/2023]
Abstract
There are conflicting reports concerning the association of motor disabilities with increased risk of mental disorders. This investigation will provide a good understanding about defining the possible association between tremor and risk of anxiety and cognitive alterations. Beside, a secondary objective of the current study was to determine the effect of erythropoietin (EPO) on harmaline-induced motor and cognitive impairments. Male Wistar rats were used for the present study. The animal model of Esential tremor (ET) was established by the intraperitoneal injection of harmaline. EPO (5000 U/kg, i.p.) administered to the animals 1 h prior to harmaline injection. Exploratory, balance, anxiety related behaviors and cognitive function were assessed using footprint, open field, wire grip, rotarod and shuttle box tests. Findings demonstrated EPO ameliorated tremor scores that was induced by harmaline. Harmaline impaired cognitive functions of the treated rats, whereas EPO showed a promising effect against the cognitive impairments induced by harmaline. EPO can be offered as a potential neuroprotective agent in the treatment of patients with ET that manifest locomotor and cognitive impairments; however, further studies are needed to clarify the exact mechanisms.
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Affiliation(s)
- Fatemeh Mohammadi
- Neuroscience Research Center, Neuropharmacology Institute, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohsen Abedini Esfahlani
- Department of Anatomical Sciences, Afzalipour Medical Faculty, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohammad Shabani
- Neuroscience Research Center, Neuropharmacology Institute, Kerman University of Medical Sciences, Kerman, Iran.
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17
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Bareš M, Apps R, Avanzino L, Breska A, D'Angelo E, Filip P, Gerwig M, Ivry RB, Lawrenson CL, Louis ED, Lusk NA, Manto M, Meck WH, Mitoma H, Petter EA. Consensus paper: Decoding the Contributions of the Cerebellum as a Time Machine. From Neurons to Clinical Applications. CEREBELLUM (LONDON, ENGLAND) 2019; 18:266-286. [PMID: 30259343 DOI: 10.1007/s12311-018-0979-5] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Time perception is an essential element of conscious and subconscious experience, coordinating our perception and interaction with the surrounding environment. In recent years, major technological advances in the field of neuroscience have helped foster new insights into the processing of temporal information, including extending our knowledge of the role of the cerebellum as one of the key nodes in the brain for this function. This consensus paper provides a state-of-the-art picture from the experts in the field of the cerebellar research on a variety of crucial issues related to temporal processing, drawing on recent anatomical, neurophysiological, behavioral, and clinical research.The cerebellar granular layer appears especially well-suited for timing operations required to confer millisecond precision for cerebellar computations. This may be most evident in the manner the cerebellum controls the duration of the timing of agonist-antagonist EMG bursts associated with fast goal-directed voluntary movements. In concert with adaptive processes, interactions within the cerebellar cortex are sufficient to support sub-second timing. However, supra-second timing seems to require cortical and basal ganglia networks, perhaps operating in concert with cerebellum. Additionally, sensory information such as an unexpected stimulus can be forwarded to the cerebellum via the climbing fiber system, providing a temporally constrained mechanism to adjust ongoing behavior and modify future processing. Patients with cerebellar disorders exhibit impairments on a range of tasks that require precise timing, and recent evidence suggest that timing problems observed in other neurological conditions such as Parkinson's disease, essential tremor, and dystonia may reflect disrupted interactions between the basal ganglia and cerebellum.The complex concepts emerging from this consensus paper should provide a foundation for further discussion, helping identify basic research questions required to understand how the brain represents and utilizes time, as well as delineating ways in which this knowledge can help improve the lives of those with neurological conditions that disrupt this most elemental sense. The panel of experts agrees that timing control in the brain is a complex concept in whom cerebellar circuitry is deeply involved. The concept of a timing machine has now expanded to clinical disorders.
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Affiliation(s)
- Martin Bareš
- First Department of Neurology, St. Anne's University Hospital and Faculty of Medicine, Masaryk University, Brno, Czech Republic.
- Department of Neurology, School of Medicine, University of Minnesota, Minneapolis, USA.
| | - Richard Apps
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Laura Avanzino
- Department of Experimental Medicine, Section of Human Physiology and Centro Polifunzionale di Scienze Motorie, University of Genoa, Genoa, Italy
- Centre for Parkinson's Disease and Movement Disorders, Ospedale Policlinico San Martino, Genoa, Italy
| | - Assaf Breska
- Department of Psychology and Helen Wills Neuroscience Institute, University of California, Berkeley, USA
| | - Egidio D'Angelo
- Neurophysiology Unit, Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
- Brain Connectivity Center, Fondazione Istituto Neurologico Nazionale Casimiro Mondino (IRCCS), Pavia, Italy
| | - Pavel Filip
- First Department of Neurology, St. Anne's University Hospital and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Marcus Gerwig
- Department of Neurology, University of Duisburg-Essen, Duisburg, Germany
| | - Richard B Ivry
- Department of Psychology and Helen Wills Neuroscience Institute, University of California, Berkeley, USA
| | - Charlotte L Lawrenson
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Elan D Louis
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA
- Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, USA
| | - Nicholas A Lusk
- Department of Psychology and Neuroscience, Duke University, Durham, NC, USA
| | - Mario Manto
- Department of Neurology, CHU-Charleroi, Charleroi, Belgium -Service des Neurosciences, UMons, Mons, Belgium
| | - Warren H Meck
- Department of Psychology and Neuroscience, Duke University, Durham, NC, USA
| | - Hiroshi Mitoma
- Medical Education Promotion Center, Tokyo Medical University, Tokyo, Japan
| | - Elijah A Petter
- Department of Psychology and Neuroscience, Duke University, Durham, NC, USA
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18
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Boonstra FM, Noffs G, Perera T, Jokubaitis VG, Vogel AP, Moffat BA, Butzkueven H, Evans A, van der Walt A, Kolbe SC. Functional neuroplasticity in response to cerebello-thalamic injury underpins the clinical presentation of tremor in multiple sclerosis. Mult Scler 2019; 26:696-705. [PMID: 30907236 DOI: 10.1177/1352458519837706] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Tremor is present in almost half of multiple sclerosis (MS) patients. The lack of understanding of its pathophysiology is hampering progress in development of treatments. OBJECTIVES To clarify the structural and functional brain changes associated with the clinical phenotype of upper limb tremor in people with MS. METHODS Fifteen healthy controls (46.1 ± 15.4 years), 27 MS participants without tremor (46.7 ± 11.6 years) and 42 with tremor (46.6 ± 11.5 years) were included. Tremor was quantified using the Bain score (0-10) for overall severity, handwriting and Archimedes spiral drawing. Functional magnetic resonance imaging activations were compared between participants groups during performance of a joystick task designed to isolate tremulous movement. Inflammation and atrophy of cerebello-thalamo-cortical brain structures were quantified. RESULTS Tremor participants were found to have atrophy of the cerebellum and thalamus, and higher ipsilateral cerebellar lesion load compared to participants without tremor (p < 0.020). We found higher ipsilateral activation in the inferior parietal lobule, the premotor cortex and supplementary motor area in MS tremor participants compared to MS participants without tremor during the joystick task. Finally, stronger activation in those areas was associated with lower tremor severity. CONCLUSION Subcortical neurodegeneration and inflammation along the cerebello-thalamo-cortical and cortical functional neuroplasticity contribute to the severity of tremor in MS.
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Affiliation(s)
- Frederique Mc Boonstra
- Department of Medicine and Radiology, University of Melbourne, Parkville, VIC, Australia
| | - Gustavo Noffs
- Department of Neurology, Royal Melbourne Hospital, Parkville, VIC, Australia/Centre for Neuroscience of Speech, University of Melbourne, Parkville, VIC, Australia
| | - Thushara Perera
- The Bionics Institute, East Melbourne, VIC, Australia/Department of Medical Bionics, University of Melbourne, Parkville, VIC, Australia
| | - Vilija G Jokubaitis
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Adam P Vogel
- Centre for Neuroscience of Speech, University of Melbourne, Parkville, VIC, Australia/The Bionics Institute, East Melbourne, VIC, Australia/Department of Neurodegeneration, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany/Redenlab, Melbourne, VIC, Australia
| | - Bradford A Moffat
- Department of Medicine and Radiology, University of Melbourne, Parkville, VIC, Australia
| | - Helmut Butzkueven
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Andrew Evans
- Department of Neurology, Royal Melbourne Hospital, Parkville, VIC, Australia/The Bionics Institute, East Melbourne, VIC, Australia
| | - Anneke van der Walt
- Department of Neurology, Royal Melbourne Hospital, Parkville, VIC, Australia/The Bionics Institute, East Melbourne, VIC, Australia/Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Scott C Kolbe
- Department of Medicine and Radiology, University of Melbourne, Parkville, VIC, Australia/Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia
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19
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Hopfner F, Deuschl G. Is essential tremor a single entity? Eur J Neurol 2017; 25:71-82. [DOI: 10.1111/ene.13454] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Accepted: 09/01/2017] [Indexed: 12/18/2022]
Affiliation(s)
- F. Hopfner
- Department of Neurology; Universitätsklinikum Schleswig-Holstein; Kiel Campus Germany
- Christian-Albrechts Universität; Kiel Germany
| | - G. Deuschl
- Department of Neurology; Universitätsklinikum Schleswig-Holstein; Kiel Campus Germany
- Christian-Albrechts Universität; Kiel Germany
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20
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Filip P, Lungu OV, Manto MU, Bareš M. Linking Essential Tremor to the Cerebellum: Physiological Evidence. THE CEREBELLUM 2017; 15:774-780. [PMID: 26530223 DOI: 10.1007/s12311-015-0740-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Essential tremor (ET), clinically characterized by postural and kinetic tremors, predominantly in the upper extremities, originates from pathological activity in the dynamic oscillatory network comprising the majority of nodes in the central motor network. Evidence indicates dysfunction in the thalamus, the olivocerebellar loops, and intermittent cortical engagement. Pathology of the cerebellum, a structure with architecture intrinsically predisposed to oscillatory activity, has also been implicated in ET as shown by clinical, neuroimaging, and pathological studies. Despite electrophysiological studies assessing cerebellar impairment in ET being scarce, their impact is tangible, as summarized in this review. The electromyography-magnetoencephalography combination provided the first direct evidence of pathological alteration in cortico-subcortical communication, with a significant emphasis on the cerebellum. Furthermore, complex electromyography studies showed disruptions in the timing of agonist and antagonist muscle activation, a process generally attributed to the cerebellum. Evidence pointing to cerebellar engagement in ET has also been found in electrooculography measurements, cerebellar repetitive transcranial magnetic stimulation studies, and, indirectly, in complex analyses of the activity of the ventral intermediate thalamic nucleus (an area primarily receiving inputs from the cerebellum), which is also used in the advanced treatment of ET. In summary, further progress in therapy will require comprehensive electrophysiological and physiological analyses to elucidate the precise mechanisms leading to disease symptoms. The cerebellum, as a major node of this dynamic oscillatory network, requires further study to aid this endeavor.
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Affiliation(s)
- Pavel Filip
- First Department of Neurology, Faculty of Medicine, Masaryk University and St. Anne's Teaching Hospital, Pekařská 53, 656 91, Brno, Czech Republic.,Central European Institute of Technology, CEITEC MU, Behavioral and Social Neuroscience Research Group, Masaryk University, Brno, Czech Republic
| | - Ovidiu V Lungu
- Department of Psychiatry, Université de Montréal, Montréal, Québec, Canada.,Functional Neuroimaging Unit, Research Center of the Geriatric Institute Affiliated with the Université de Montréal, Montréal, Québec, Canada
| | | | - Martin Bareš
- First Department of Neurology, Faculty of Medicine, Masaryk University and St. Anne's Teaching Hospital, Pekařská 53, 656 91, Brno, Czech Republic. .,Central European Institute of Technology, CEITEC MU, Behavioral and Social Neuroscience Research Group, Masaryk University, Brno, Czech Republic. .,Department of Neurology, School of Medicine, University of Minnesota, Minneapolis, MN, USA.
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21
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Azevedo MFAD, Meyer A. [Essential tremor in endemic disease control agents exposed to pesticides: a case-control study]. CAD SAUDE PUBLICA 2017; 33:e00194915. [PMID: 28832787 DOI: 10.1590/0102-311x00194915] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 10/25/2016] [Indexed: 11/22/2022] Open
Abstract
Tremor is the most frequent movement disorder in the population and can be associated with pesticide exposure. The aim was to assess the odds of essential tremor in 442 endemic disease control agents in Rio de Janeiro State, Brazil, exposed to pesticides. Fifty-one cases and 204 controls were selected (1:4). All participants answered a questionnaire on socio-demographic, occupational, and toxicological items. The influence of pesticide exposure on the development of tremor was estimated by non-conditional logistic regression, adjusted for selected covariables. Mean age of the study population was 49 (SD = 7) years, and the difference between cases (mean = 50.8; SD = 6.9) and controls (mean = 48.5; SD = 6.9) was statistically significant (p = 0.03). Those with 16 to 16.9 years of pesticide use showed the highest odds of essential tremor (adjusted OR = 4.60; 95%CI: 1.29-16.41). Our results suggest that 16 to 16.9 years of pesticide exposure had a major impact on the development of essential tremor.
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Affiliation(s)
| | - Armando Meyer
- Instituto de Estudos em Saúde Coletiva, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil
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22
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Gövert F, Becktepe JS, Deuschl G. Current concepts of essential tremor. Rev Neurol (Paris) 2016; 172:416-422. [PMID: 27561441 DOI: 10.1016/j.neurol.2016.07.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 07/18/2016] [Indexed: 01/27/2023]
Abstract
Essential tremor is clinically defined but there is increasing evidence that it is not a unique entity. Its pathophysiology has been studied with many methods but may also vary between subtypes. Neurophysiologically, there is strong evidence that a specific cerebello-thalamo-cortical loop is abnormally oscillating. The cause of its uncontrolled oscillation is not yet understood. The clear proof of a degenerative cause is still lacking and abnormal receptors or other causes of altered non-progressive functional disturbance cannot be excluded. Strong evidence supports the major involvement of the cerebellum and there is ample evidence that GABA is the main neurotransmitter involved in the pathophysiology in ET. Genetics have provided so far only a few rare subtypes which are due to specific mutations but there is no doubt that it is mostly a hereditary condition. There is evidence that the large subgroup of late onset tremor is a separate condition and this tremor is an independent risk factor for earlier mortality and comes with signs of premature aging (aging-related tremor). It will be important to improve phenotyping of patients in more detail possibly to include not only features of the tremor itself but also other clinical assessments like force measurements or cognitive testing. Based on these variables, we may be able to better understand the presumably different mechanisms underlying different variants of the disease.
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Affiliation(s)
- F Gövert
- Department of Neurology, Christian-Albrecht University of Kiel, Universitätsklinikum Schleswig-Holstein, Kiel Campus, Schittenhelmstrasse 10, 24105 Kiel, Germany
| | - J S Becktepe
- Department of Neurology, Christian-Albrecht University of Kiel, Universitätsklinikum Schleswig-Holstein, Kiel Campus, Schittenhelmstrasse 10, 24105 Kiel, Germany
| | - G Deuschl
- Department of Neurology, Christian-Albrecht University of Kiel, Universitätsklinikum Schleswig-Holstein, Kiel Campus, Schittenhelmstrasse 10, 24105 Kiel, Germany.
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23
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Ben-Soussan TD, Glicksohn J, Berkovich-Ohana A. From Cerebellar Activation and Connectivity to Cognition: A Review of the Quadrato Motor Training. BIOMED RESEARCH INTERNATIONAL 2015; 2015:954901. [PMID: 26539545 PMCID: PMC4619922 DOI: 10.1155/2015/954901] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 05/06/2015] [Indexed: 11/18/2022]
Abstract
The importance of the cerebellum is increasingly recognized, not only in motor control but also in cognitive learning and function. Nevertheless, the relationship between training-induced cerebellar activation and electrophysiological and structural changes in humans has yet to be established. In the current paper, we suggest a general model tying cerebellar function to cognitive improvement, via neuronal synchronization, as well as biochemical and anatomical changes. We then suggest that sensorimotor training provides an optimal paradigm to test the proposed model and review supporting evidence of Quadrato Motor Training (QMT), a sensorimotor training aimed at increasing attention and coordination. Subsequently, we discuss the possible mechanisms through which QMT may exert its beneficial effects on cognition (e.g., increased creativity, reflectivity, and reading), focusing on cerebellar alpha activity as a possible mediating mechanism allowing cognitive improvement, molecular and anatomical changes. Using the example of QMT research, this paper emphasizes the importance of investigating whole-body sensorimotor training paradigms utilizing a multidisciplinary approach and its implications to healthy brain development.
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Affiliation(s)
- Tal Dotan Ben-Soussan
- The Leslie and Susan Gonda (Goldschmied) Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
- Research Institute for Neuroscience, Education and Didactics, Patrizio Paoletti Foundation, Rome, Italy
| | - Joseph Glicksohn
- The Leslie and Susan Gonda (Goldschmied) Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
- Department of Criminology, Bar-Ilan University, Ramat Gan, Israel
| | - Aviva Berkovich-Ohana
- Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
- Department of Physiology and Pharmacology, University of Rome “La Sapienza”, Rome, Italy
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24
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News and controversies regarding essential tremor. Rev Neurol (Paris) 2015; 171:415-25. [DOI: 10.1016/j.neurol.2015.02.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/01/2015] [Accepted: 02/02/2015] [Indexed: 01/08/2023]
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25
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Assessment of Movement Disorders in Rodents. Mov Disord 2015. [DOI: 10.1016/b978-0-12-405195-9.00004-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Paek SB, Min HK, Kim I, Knight EJ, Baek JJ, Bieber AJ, Lee KH, Chang SY. Frequency-dependent functional neuromodulatory effects on the motor network by ventral lateral thalamic deep brain stimulation in swine. Neuroimage 2014; 105:181-8. [PMID: 25451479 DOI: 10.1016/j.neuroimage.2014.09.064] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 09/03/2014] [Accepted: 09/27/2014] [Indexed: 01/07/2023] Open
Abstract
Thalamic deep brain stimulation (DBS) is an FDA-approved neurosurgical treatment for medication-refractory essential tremor. Its therapeutic benefit is highly dependent upon stimulation frequency and voltage parameters. We investigated these stimulation parameter-dependent effects on neural network activation by performing functional magnetic resonance imaging (fMRI) during DBS of the ventral lateral (VL) thalamus and comparing the blood oxygenation level-dependent (BOLD) signals induced by multiple stimulation parameter combinations in a within-subject study of swine. Low (10 Hz) and high (130 Hz) frequency stimulation was applied at 3, 5, and 7 V in the VL thalamus of normal swine (n = 5). We found that stimulation frequency and voltage combinations differentially modulated the brain network activity in the sensorimotor cortex, the basal ganglia, and the cerebellum in a parameter-dependent manner. Notably, in the motor cortex, high frequency stimulation generated a negative BOLD response, while low frequency stimulation increased the positive BOLD response. These frequency-dependent differential effects suggest that the VL thalamus is an exemplary target for investigating functional network connectivity associated with therapeutic DBS.
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Affiliation(s)
- Seungleal B Paek
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Hoon-Ki Min
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Inyong Kim
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Emily J Knight
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
| | - James J Baek
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Allan J Bieber
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA; Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - Kendall H Lee
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA.
| | - Su-Youne Chang
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA.
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Bendersky D, Ajler P, Yampolsky C. [The use of neuromodulation for the treatment of tremor]. Surg Neurol Int 2014; 5:S232-46. [PMID: 25165613 PMCID: PMC4138824 DOI: 10.4103/2152-7806.137944] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 11/29/2012] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Tremor may be a disabling disorder and pharmacologic treatment is the first-line therapy for these patients. Nevertheless, this treatment may lead to a satisfactory tremor reduction in only 50% of patients with essential tremor. Thalamotomy was the treatment of choice for tremor refractory to medical therapy until deep brain stimulation (DBS) of the ventral intermedius nucleus (Vim) of the thalamus has started being used. Nowadays, thalamotomy is rarely performed. METHODS This article is a non-systematic review of the indications, results, programming parameters and surgical technique of DBS of the Vim for the treatment of tremor. RESULTS In spite of the fact that it is possible to achieve similar clinical results using thalamotomy or DBS of the Vim, the former causes more adverse effects than the latter. Furthermore, DBS can be used bilaterally, whereas thalamotomy has a high risk of causing disartria when it is performed in both sides. DBS of the Vim achieved an adequate tremor improvement in several series of patients with tremor caused by essential tremor, Parkinson's disease or multiple sclerosis. Besides the Vim, there are other targets, which are being used by some authors, such as the zona incerta and the prelemniscal radiations. CONCLUSION DBS of the Vim is a useful treatment for disabling tremor refractory to medical therapy. It is essential to carry out an accurate patient selection as well as to use a proper surgical technique. The best stereotactic target for tremor is still unknown, although the Vim is the most used one.
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Affiliation(s)
- Damián Bendersky
- Department of Neurosurgery, Hospital Italiano de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
| | - Pablo Ajler
- Department of Neurosurgery, Hospital Italiano de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
| | - Claudio Yampolsky
- Department of Neurosurgery, Hospital Italiano de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
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Schmouth JF, Dion PA, Rouleau GA. Genetics of essential tremor: From phenotype to genes, insights from both human and mouse studies. Prog Neurobiol 2014; 119-120:1-19. [DOI: 10.1016/j.pneurobio.2014.05.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 04/16/2014] [Accepted: 05/02/2014] [Indexed: 11/30/2022]
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Philippens IH, Joosen MJ, Ahnaou A, Andres I, Drinkenburg W(PH. Anti-Parkinson effects of a selective alpha2C-adrenoceptor antagonist in the MPTP marmoset model. Behav Brain Res 2014; 269:81-6. [DOI: 10.1016/j.bbr.2014.04.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 04/14/2014] [Accepted: 04/18/2014] [Indexed: 01/08/2023]
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Ossowska K, Wardas J, Berghauzen-Maciejewska K, Głowacka U, Kuter K, Pilc A, Zorn SH, Doller D. Lu AF21934, a positive allosteric modulator of mGlu4 receptors, reduces the harmaline-induced hyperactivity but not tremor in rats. Neuropharmacology 2014; 83:28-35. [PMID: 24726309 DOI: 10.1016/j.neuropharm.2014.03.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 02/18/2014] [Accepted: 03/31/2014] [Indexed: 12/19/2022]
Abstract
Harmaline induces tremor in animals resembling essential tremor which has been suggested to result from activation of the glutamatergic olivo-cerebellar projection. The aim of the present study was to examine the effects of systemic administration of Lu AF21934, a brain-penetrating positive allosteric modulator of the metabotropic glutamate receptor 4 (mGlu4), on the harmaline-induced tremor and other forms of motor activity in rats using fully automated Force Plate Actimeters. The influence of harmaline on the mGlu4 mRNA expression in the cerebellum and inferior olive was analysed by in situ hybridization. Harmaline at a dose of 15 mg/kg (ip) triggered tremor which was manifested by an increase in the power within 9-15 Hz band and in the tremor index (a difference in power between bands 9-15 Hz and 0-8 Hz). Harmaline induced a biphasic effect on mobility, initially inhibiting the exploratory locomotor activity of rats (0-30 min after administration), followed by an increase in their basic activity. Lu AF21934 (0.5-5 mg/kg sc) did not influence tremor but at doses of 0.5 and 2.5 mg/kg reversed harmaline-induced hyperactivity. MGlu4 mRNA expression was high in the cerebellar cortex and low in the inferior olive. Repeated harmaline (15 mg/kg ip once a day for 5 days] decreased mGlu4 mRNA in the cerebellum and inferior olive. The present study indicates that the mGlu4 stimulation counteracts hyperactivity induced by harmaline which suggests the involvement of cerebellar glutamatergic transmission in this process. In contrast, neuronal mechanisms involved in tremor seem to be insensitive to the stimulation of mGlu4.
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Affiliation(s)
- Krystyna Ossowska
- Department of Neuro-Psychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna St., 31-343 Kraków, Poland.
| | - Jadwiga Wardas
- Department of Neuro-Psychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna St., 31-343 Kraków, Poland
| | - Klemencja Berghauzen-Maciejewska
- Department of Neuro-Psychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna St., 31-343 Kraków, Poland
| | - Urszula Głowacka
- Department of Neuro-Psychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna St., 31-343 Kraków, Poland
| | - Katarzyna Kuter
- Department of Neuro-Psychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna St., 31-343 Kraków, Poland
| | - Andrzej Pilc
- Department of Neurobiology, Institute of Pharmacology, Polish Academy of Sciences, 12, Smętna St., 31-343 Kraków, Poland
| | - Stevin H Zorn
- Discovery Chemistry & DMPK, Lundbeck Research USA, 215 College Road, Paramus, NJ 07652, USA
| | - Dario Doller
- Discovery Chemistry & DMPK, Lundbeck Research USA, 215 College Road, Paramus, NJ 07652, USA
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Effects of alprazolam on cortical activity and tremors in patients with essential tremor. PLoS One 2014; 9:e93159. [PMID: 24667763 PMCID: PMC3965529 DOI: 10.1371/journal.pone.0093159] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 03/01/2014] [Indexed: 11/19/2022] Open
Abstract
Background Essential tremor (ET) is characterised by postural and action tremors with a frequency of 4–12 Hz. Previous studies suggest that the tremor activity originates in the cerebello-thalamocortical pathways. Alprazolam is a short-acting benzodiazepine that attenuates tremors in ET. The mechanisms that mediate the therapeutic action of alprazolam are unknown; however, in healthy subjects, benzodiazepines increase cortical beta activity. In this study, we investigated the effect of alprazolam both on beta and tremor-related cortical activity and on alterations in tremor presentation in ET patients. Therefore, we characterised the dynamics of tremor and cortical activity in ET patients after alprazolam intake. Methods We recorded hand tremors and contralateral cortical activity in four recordings before and after a single dose of alprazolam. We then computed the changes in tremors, cortico-muscular coherence, and cortical activity at the tremor frequency and in the beta band. Results Alprazolam significantly attenuated tremors (EMG: 76.2±22.68%), decreased cortical activity in the tremor frequency range and increased cortical beta activity in all patients (P<0.05). At the same time, the cortico-muscular coherence at the tremor frequency became non-significant (P<0.05). We also found a significant correlation (r = 0.757, P<0.001) between the reduction in tremor severity and the increased ratio of cortical activity in the beta band to the activity observed in the tremor frequency range. Conclusions This study provides the first quantitative analysis of tremor reduction following alprazolam intake. We observed that the tremor severity decreased in association with an increased ratio of beta to tremor-related cortical activity. We hypothesise that the increase in cortical beta activity may act as a blocking mechanism and may dampen the pathological oscillatory activity, which in turn attenuates the observed tremor.
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Gallego JÁ, Rocon E, Belda-Lois JM, Pons JL. A neuroprosthesis for tremor management through the control of muscle co-contraction. J Neuroeng Rehabil 2013; 10:36. [PMID: 23587119 PMCID: PMC3661364 DOI: 10.1186/1743-0003-10-36] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 03/25/2013] [Indexed: 11/16/2022] Open
Abstract
Background Pathological tremor is the most prevalent movement disorder. Current treatments do not attain a significant tremor reduction in a large proportion of patients, which makes tremor a major cause of loss of quality of life. For instance, according to some estimates, 65% of those suffering from upper limb tremor report serious difficulties during daily living. Therefore, novel forms for tremor management are required. Since muscles intrinsically behave as a low pass filter, and tremor frequency is above that of volitional movements, the authors envisioned the exploitation of these properties as a means of developing a novel treatment alternative. This treatment would rely on muscle co-contraction for tremor management, similarly to the strategy employed by the intact central nervous system to stabilize a limb during certain tasks. Methods We implemented a neuroprosthesis that regulated the level of muscle co-contraction by injecting current at a pair of antagonists through transcutaneous neurostimulation. Co-contraction was adapted to the instantaneous parameters of tremor, which were estimated from the raw recordings of a pair of solid state gyroscopes with a purposely designed adaptive algorithm. For the experimental validation, we enrolled six patients suffering from parkinsonian or essential tremor of different severity, and evaluated the effect of the neuroprosthesis during standard tasks employed for neurological examination. Results The neuroprosthesis attained significant attenuation of tremor (p<0.001), and reduced its amplitude up to a 52.33±25.48%. Furthermore, it alleviated both essential and parkinsonian tremor in spite of their different etiology and symptomatology. Tremor severity was not a limiting factor on the performance of the neuroprosthesis, although there was a subtle trend towards larger attenuation of more severe tremors. Tremor frequency was not altered during neurostimulation, as expected from the central origin of Parkinson’s disease and essential tremor. All patients showed a good tolerance to neurostimulation in terms of comfort and absence of pain, and some spontaneously reported that they felt that tremor was reduced when the neuroprosthesis was activated. Conclusions The results presented herein demonstrate that the neuroprosthesis provides systematic attenuation of the two major types of tremor, irrespectively from their severity. This study sets the basis for the validation of the neuroprosthesis as an alternative, non-invasive means for tremor management.
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Affiliation(s)
- Juan Álvaro Gallego
- Bioengineering Group, Consejo Superior de Investigaciones Científicas (CSIC), Ctra Campo Real km 0.2-La Poveda, 28500 Arganda del Rey, Spain.
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Podurgiel S, Collins-Praino LE, Yohn S, Randall PA, Roach A, Lobianco C, Salamone JD. Tremorolytic effects of safinamide in animal models of drug-induced parkinsonian tremor. Pharmacol Biochem Behav 2013; 105:105-11. [DOI: 10.1016/j.pbb.2013.01.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2012] [Revised: 01/16/2013] [Accepted: 01/19/2013] [Indexed: 01/02/2023]
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Rahimi Shourmasti F, Goudarzi I, Lashkarbolouki T, Abrari K, Elahdadi Salmani M, Goudarzi A. Effects of riluzole on harmaline induced tremor and ataxia in rats: Biochemical, histological and behavioral studies. Eur J Pharmacol 2012; 695:40-7. [DOI: 10.1016/j.ejphar.2012.08.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 08/26/2012] [Accepted: 08/27/2012] [Indexed: 11/30/2022]
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Schniepp R, Jakl V, Wuehr M, Havla J, Kümpfel T, Dieterich M, Strupp M, Jahn K. Treatment with 4-aminopyridine improves upper limb tremor of a patient with multiple sclerosis: a video case report. Mult Scler 2012; 19:506-8. [PMID: 23069878 DOI: 10.1177/1352458512461394] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The reversible potassium channel blocker 4-aminopyridine is effective in the treatment of numerous cerebellar dysfunctions, such as episodic ataxia type 2 and downbeat nystagmus syndrome. In 2011, its sustained release form, dalfampridine, was admitted in Europe for the treatment of walking difficulties in patients with multiple sclerosis (MS). Here we report the case of a 44-year old patient with a progressive MS whose upper limb tremor was markedly reduced under treatment with 4-aminopyridine, as documented in a Tremor Activities of Daily Living questionnaire and in the 9-Hole Peg test. Hand accelerations decreased in the left hand from 10.9 m/sec(2) to 2.2 m/sec(2) and in the right hand from 4.2 m/sec(2) to 0.9 m/sec(2). This case report indicates for the first time that 4-aminopyridine might be effective in the symptomatic treatment of tremor entities in patients with MS. The finding calls for further prospective studies to determine the usefulness of 4-aminopyridine or its sustained-release form dalfampridine in treating patients with tremor and MS.
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Affiliation(s)
- Roman Schniepp
- Department of Neurology, University of Munich, Munich, Germany.
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Labiano-Fontcuberta A, Benito-León J. Understanding tremor in multiple sclerosis: prevalence, pathological anatomy, and pharmacological and surgical approaches to treatment. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2012; 2. [PMID: 23439953 PMCID: PMC3500135 DOI: 10.7916/d8z60mr3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/02/2012] [Accepted: 07/06/2012] [Indexed: 12/01/2022]
Abstract
Background Given that tremor is one of the most prevalent and disabling features of multiple sclerosis (MS), we will review the most significant milestones in tremor in this disease in recent years, focusing on prevalence, clinical features, anatomical basis, and treatment. Methods Data for this review were identified by searching MEDLINE with the search terms “multiple sclerosis” and “tremor”. References were also identified from relevant articles published between January 1966 and May 2012. Results The predominant type of MS tremor is a large-amplitude, postural, and kinetic tremor, which most commonly affects the arms, although tremor can also involve head, neck, vocal cords, and trunk. Involvement of the tongue, jaw, or palate has not been reported. Although the anatomical basis underlying tremor in MS is poorly understood, the link between the cerebellum and the MS-related tremor is supported by clinical and experimental studies. Currently available medication is often unsuccessful in most cases. Surgical treatment can be a satisfactory alternative to treat severe and disabling tremor. Discussion Tremor in MS patients could be considered as an advanced consequence of the disease and its presence suggests a more aggressive course. MS tremor can be severe and very disabling for a small group of patients. Treatment of MS tremor remains a great challenge. Recent studies suggest that dissociating tremor from cerebellar dysfunction using selected clinical tests would be the key issue to successful surgical treatment. Understanding the pathophysiology and biochemistry of tremor production in MS may lead to new therapeutic approaches.
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Affiliation(s)
- Andrés Labiano-Fontcuberta
- Department of Neurology, University Hospital "12 de Octubre", Madrid, Spain ; Department of Medicine, Complutense University, Madrid, Spain
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Collins-Praino LE, Podurgiel SJ, Kovner R, Randall PA, Salamone JD. Extracellular GABA in globus pallidus increases during the induction of oral tremor by haloperidol but not by muscarinic receptor stimulation. Behav Brain Res 2012; 234:129-35. [DOI: 10.1016/j.bbr.2012.06.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 06/07/2012] [Accepted: 06/12/2012] [Indexed: 11/28/2022]
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Dovzhenok A, Rubchinsky LL. On the origin of tremor in Parkinson's disease. PLoS One 2012; 7:e41598. [PMID: 22848541 PMCID: PMC3407214 DOI: 10.1371/journal.pone.0041598] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 06/25/2012] [Indexed: 11/19/2022] Open
Abstract
The exact origin of tremor in Parkinson’s disease remains unknown. We explain why the existing data converge on the basal ganglia-thalamo-cortical loop as a tremor generator and consider a conductance-based model of subthalamo-pallidal circuits embedded into a simplified representation of the basal ganglia-thalamo-cortical circuit to investigate the dynamics of this loop. We show how variation of the strength of dopamine-modulated connections in the basal ganglia-thalamo-cortical loop (representing the decreasing dopamine level in Parkinson’s disease) leads to the occurrence of tremor-like burst firing. These tremor-like oscillations are suppressed when the connections are modulated back to represent a higher dopamine level (as it would be the case in dopaminergic therapy), as well as when the basal ganglia-thalamo-cortical loop is broken (as would be the case for ablative anti-parkinsonian surgeries). Thus, the proposed model provides an explanation for the basal ganglia-thalamo-cortical loop mechanism of tremor generation. The strengthening of the loop leads to tremor oscillations, while the weakening or disconnection of the loop suppresses them. The loop origin of parkinsonian tremor also suggests that new tremor-suppression therapies may have anatomical targets in different cortical and subcortical areas as long as they are within the basal ganglia-thalamo-cortical loop.
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Affiliation(s)
- Andrey Dovzhenok
- Department of Mathematical Sciences and Center for Mathematical Biosciences, Indiana University Purdue University Indianapolis, Indianapolis, Indiana, United States of America
| | - Leonid L. Rubchinsky
- Department of Mathematical Sciences and Center for Mathematical Biosciences, Indiana University Purdue University Indianapolis, Indianapolis, Indiana, United States of America
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- * E-mail:
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Cavallo G, Campolo D, Keller F, Guglielmelli E. A Modular Platform for In-plane Ground Reaction Forces Detection in a Mouse Model: Design, Development and Verification. Adv Robot 2012. [DOI: 10.1163/156855308x291872] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Giuseppe Cavallo
- a Biomedical Robotics & Biomicrosystem Lab, Università Campus Bio-Medico di Roma, 00128 Trigoni (Rome), Italy;,
| | - Domenico Campolo
- b Biomedical Robotics & Biomicrosystem Lab, Università Campus Bio-Medico di Roma, 00128 Trigoni (Rome), Italy
| | - Flavio Keller
- c Developmental Neuroscience and Neural Plasticity Lab, Università Campus Bio-Medico di Roma, 0100 Rome, Italy
| | - Eugenio Guglielmelli
- d Biomedical Robotics & Biomicrosystem Lab, Università Campus Bio-Medico di Roma, 00128 Trigoni (Rome), Italy
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Miwa H, Kondo T. T-type calcium channel as a new therapeutic target for tremor. THE CEREBELLUM 2012; 10:563-9. [PMID: 21479969 DOI: 10.1007/s12311-011-0277-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Voltage-gated calcium channels play an important role in many physiological and pathological processes. Accumulating studies suggest that the T-type calcium channel is a potential target for the treatment of various neurological disorders, such as epilepsy, insomnia, and neuropathic pain. Here, we highlight recent advances in our understanding of T-type calcium channel regulation and their implications for tremor disorders. Several T-type calcium channel blockers effectively suppressed experimental tremors that have been suggested to originate from either the cerebellum or basal ganglia. Among T-type calcium channel blockers that have been used clinically, the anti-tremor efficacy of zonisamide garnered our attention. Based on both basic and clinical studies, the possibility is emerging that T-type calcium channel blockers that transit into the central nervous system may have therapeutic potentials for tremor disorders.
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Affiliation(s)
- Hideto Miwa
- Department of Neurology, Wakayama Medical University, 811-1 Kimiidera, Wakayama, 641-8510, Japan.
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Xiang Z, Thompson AD, Brogan JT, Schulte ML, Melancon BJ, Mi D, Lewis LM, Zou B, Yang L, Morrison R, Santomango T, Byers F, Brewer K, Aldrich JS, Yu H, Dawson ES, Li M, McManus O, Jones CK, Daniels JS, Hopkins CR, Xie XS, Conn PJ, Weaver CD, Lindsley CW. The Discovery and Characterization of ML218: A Novel, Centrally Active T-Type Calcium Channel Inhibitor with Robust Effects in STN Neurons and in a Rodent Model of Parkinson's Disease. ACS Chem Neurosci 2011; 2:730-742. [PMID: 22368764 DOI: 10.1021/cn200090z] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
T-type Ca(2+) channel inhibitors hold tremendous therapeutic potential for the treatment of pain, epilepsy, sleep disorders, essential tremor and other neurological disorders; however, a lack of truly selective tools has hindered basic research, and selective tools from the pharmaceutical industry are potentially burdened with intellectual property (IP) constraints. Thus, an MLPCN high-throughput screen (HTS) was conducted to identify novel T-type Ca(2+) channel inhibitors free from IP constraints, and freely available through the MLPCN, for use by the biomedical community to study T-type Ca(2+) channels. While the HTS provided numerous hits, these compounds could not be optimized to the required level of potency to be appropriate tool compounds. Therefore, a scaffold hopping approach, guided by SurflexSim, ultimately afforded ML218 (CID 45115620) a selective T-Type Ca(2+) (Ca(v)3.1, Ca(v)3.2, Ca(v)3.3) inhibitor (Ca(v)3.2, IC(50) = 150 nM in Ca(2+) flux; Ca(v)3.2 IC(50) = 310 nM and Ca(v)3.3 IC(50) = 270 nM, respectively in patch clamp electrophysiology) with good DMPK properties, acceptable in vivo rat PK and excellent brain levels. Electrophysiology studies in subthalamic nucleus (STN) neurons demonstrated robust effects of ML218 on the inhibition of T-Type calcium current, inhibition of low threshold spike and rebound burst activity. Based on the basal ganglia circuitry in Parkinson's disease (PD), the effects of ML218 in STN neurons suggest a therapeutic role for T-type Ca(2+) channel inhibitors, and ML218 was found to be orally efficacious in haloperidol-induced catalepsy, a preclinical PD model, with comparable efficacy to an A(2A) antagonist, a clinically validated PD target. ML218 proves to be a powerful new probe to study T-Type Ca(2+) function in vitro and in vivo, and freely available.
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Affiliation(s)
| | | | | | | | | | | | | | - Bende Zou
- AfaSci Research Laboratory, AfaSci, Inc., Redwood, California 94063, United States
| | - Liya Yang
- AfaSci Research Laboratory, AfaSci, Inc., Redwood, California 94063, United States
| | | | | | | | | | | | | | | | | | | | | | | | | | - Ximin Simon Xie
- AfaSci Research Laboratory, AfaSci, Inc., Redwood, California 94063, United States
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Collins-Praino LE, Paul NE, Rychalsky KL, Hinman JR, Chrobak JJ, Senatus PB, Salamone JD. Pharmacological and physiological characterization of the tremulous jaw movement model of parkinsonian tremor: potential insights into the pathophysiology of tremor. Front Syst Neurosci 2011; 5:49. [PMID: 21772815 PMCID: PMC3131529 DOI: 10.3389/fnsys.2011.00049] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 06/03/2011] [Indexed: 11/13/2022] Open
Abstract
Tremor is a cardinal symptom of parkinsonism, occurring early on in the disease course and affecting more than 70% of patients. Parkinsonian resting tremor occurs in a frequency range of 3-7 Hz and can be resistant to available pharmacotherapy. Despite its prevalence, and the significant decrease in quality of life associated with it, the pathophysiology of parkinsonian tremor is poorly understood. The tremulous jaw movement (TJM) model is an extensively validated rodent model of tremor. TJMs are induced by conditions that also lead to parkinsonism in humans (i.e., striatal DA depletion, DA antagonism, and cholinomimetic activity) and reversed by several antiparkinsonian drugs (i.e., DA precursors, DA agonists, anticholinergics, and adenosine A(2A) antagonists). TJMs occur in the same 3-7 Hz frequency range seen in parkinsonian resting tremor, a range distinct from that of dyskinesia (1-2 Hz), and postural tremor (8-14 Hz). Overall, these drug-induced TJMs share many characteristics with human parkinsonian tremor, but do not closely resemble tardive dyskinesia. The current review discusses recent advances in the validation of the TJM model, and illustrates how this model is being used to develop novel therapeutic strategies, both surgical and pharmacological, for the treatment of parkinsonian resting tremor.
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Affiliation(s)
- Lyndsey E Collins-Praino
- Behavioral Neuroscience Division, Department of Psychology, University of Connecticut Storrs, CT, USA
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Barbe MT, Liebhart L, Runge M, Deyng J, Florin E, Wojtecki L, Schnitzler A, Allert N, Sturm V, Fink GR, Maarouf M, Timmermann L. Deep brain stimulation of the ventral intermediate nucleus in patients with essential tremor: Stimulation below intercommissural line is more efficient but equally effective as stimulation above. Exp Neurol 2011; 230:131-7. [DOI: 10.1016/j.expneurol.2011.04.005] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 03/14/2011] [Accepted: 04/07/2011] [Indexed: 11/26/2022]
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Iseri PK, Karson A, Gullu KM, Akman O, Kokturk S, Yardýmoglu M, Erturk S, Ates N. The effect of memantine in harmaline-induced tremor and neurodegeneration. Neuropharmacology 2011; 61:715-23. [PMID: 21640732 DOI: 10.1016/j.neuropharm.2011.05.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2011] [Revised: 05/12/2011] [Accepted: 05/16/2011] [Indexed: 10/18/2022]
Abstract
Essential tremor (ET) is one of the most common and most disabling movement disorders among adults. The drug treatment of ET remains unsatisfactory. Additional therapies are required for patients with inadequate response or intolerable side effects. The current study aims to investigate the anti-tremogenic and neuroprotective effects of memantine (NMDA receptor antagonist) on the harmaline model of transient action tremor. The effects of memantine were further compared with ethanol. Three separate groups of male Wistar rats were injected either with saline, ethanol (1.5 gr/kg), or memantine (5 mg/kg) 15 min prior to a single intraperitoneal injection of harmaline (20 mg/kg). Tremor and locomotion were evaluated by a custom-built tremor and locomotion analysis system. After 24 h of harmaline injection, cellular viability, and apoptosis were assessed using crystal violet staining, and caspase-3 immunostaining, respectively. Harmaline caused neuronal cell loss and caspase-3 mediated apoptosis in cerebellar granular and purkinje cells as well as the inferior olivary neurons. Despite a reduction in tremor intensity and duration with ethanol, this compound resulted in cell loss in cerebellum and olivary nucleus. Memantine exhibited neuroprotective efficacy on cerebellar and inferior olivary neurons albeit weaker anti-tremor effect compared to ethanol. In conclusion, anti-tremogenic and neuroprotective effects do not necessarily overlap. Memantine is a potential treatment for ET particularly given its neuroprotective efficacy.
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Affiliation(s)
- Pervin K Iseri
- Department of Neurology, Kocaeli University Medical School, Kocaeli, Turkey.
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Head tremor secondary to MS resolved with rituximab. Neurol Sci 2011; 32:1157-60. [PMID: 21556869 DOI: 10.1007/s10072-011-0600-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Accepted: 04/22/2011] [Indexed: 10/18/2022]
Abstract
We describe the case of a 33-year-old woman who presented with a 2-month history of worsening head tremor. The medical evaluation led to the new diagnosis of MS and the MRI of brain demonstrated prominently active disease. Intravenous rituximab was started according to the HERMES trial, and significant improvement was noted. She has received additional rituximab dosing approximately every 6 months, and at the 2-year follow-up the tremor has not recurred. The resolution of head tremor likely resulted from the complete suppression of MS disease activity, which must have allowed restoration of normal neural circuitry. In agreement with a growing body of evidence that supports early control of MS disease activity to prevent accumulation of fixed disability, this case advocates for aggressive immunological therapy at the onset of tremor in MS patients.
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Abstract
Tremor is the most common movement disorder presenting to an outpatient neurology practice and is defined as a rhythmical, involuntary oscillatory movement of a body part. The authors review the clinical examination, classification, and diagnosis of tremor. The pathophysiology of the more common forms of tremor is outlined, and treatment options are discussed. Essential tremor is characterized primarily by postural and action tremors, may be a neurodegenerative disorder with pathologic changes in the cerebellum, and can be treated with a wide range of pharmacologic and nonpharmacologic methods. Tremor at rest is typical for Parkinson's disease, but may arise independently of a dopaminergic deficit. Enhanced physiologic tremor, intention tremor, and dystonic tremor are discussed. Further differential diagnoses described in this review include drug- or toxin-induced tremor, neuropathic tremor, psychogenic tremor, orthostatic tremor, palatal tremor, tremor in Wilson's disease, and tremor secondary to cerebral lesions, such as Holmes' tremor (midbrain tremor). An individualized approach to treatment of tremor patients is important, taking into account the degree of disability, including social embarrassment, which the tremor causes in the patient's life.
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Effects of T-type calcium channel blockers on a parkinsonian tremor model in rats. Pharmacol Biochem Behav 2011; 97:656-9. [DOI: 10.1016/j.pbb.2010.11.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 11/15/2010] [Accepted: 11/18/2010] [Indexed: 11/19/2022]
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Gironell A, Pagonabarraga J, Pascual-Sedano B, Kulisevsky J. Lacosamide, another therapeutic failure in essential tremor: an open-label trial. Mov Disord 2010; 26:183-4. [PMID: 20925072 DOI: 10.1002/mds.23296] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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