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Wang J, Zhang Y, Yang H, Tian E, Guo Z, Chen J, Qiao C, Jiang H, Guo J, Zhou Z, Luo Q, Shi S, Yao H, Lu Y, Zhang S. Advanced progress of vestibular compensation in vestibular neural networks. CNS Neurosci Ther 2024; 30:e70037. [PMID: 39268632 PMCID: PMC11393560 DOI: 10.1111/cns.70037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2024] [Revised: 08/12/2024] [Accepted: 08/27/2024] [Indexed: 09/17/2024] Open
Abstract
Vestibular compensation is the natural process of recovery that occurs with acute peripheral vestibular lesion. Here, we summarize the current understanding of the mechanisms underlying vestibular compensation, focusing on the role of the medial vestibular nucleus (MVN), the central hub of the vestibular system, and its associated neural networks. The disruption of neural activity balance between the bilateral MVNs underlies the vestibular symptoms after unilateral vestibular damage, and this balance disruption can be partially reversed by the mutual inhibitory projections between the bilateral MVNs, and their top-down regulation by other brain regions via different neurotransmitters. However, the detailed mechanism of how MVN is involved in vestibular compensation and regulated remains largely unknown. A deeper understanding of the vestibular neural network and the neurotransmitter systems involved in vestibular compensation holds promise for improving treatment outcomes and developing more effective interventions for vestibular disorders.
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Affiliation(s)
- Jun Wang
- Department of Otorhinolaryngology, Head and Neck Surgery, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
- National Clinical Research Center for Otolaryngologic Diseases, Jiangxi Branch Center, Nanchang, China
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yuejin Zhang
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Department of Physiology, School of Basic Medicine, Huazhong University of Science and Technology, Wuhan, China
| | - Huajing Yang
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - E Tian
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhaoqi Guo
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jingyu Chen
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Caijuan Qiao
- Department of Physiology, School of Basic Medicine, Huazhong University of Science and Technology, Wuhan, China
| | - Hongqun Jiang
- Department of Otorhinolaryngology, Head and Neck Surgery, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
- National Clinical Research Center for Otolaryngologic Diseases, Jiangxi Branch Center, Nanchang, China
| | - Jiaqi Guo
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhanghong Zhou
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qing Luo
- Department of Otorhinolaryngology, Head and Neck Surgery, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
- National Clinical Research Center for Otolaryngologic Diseases, Jiangxi Branch Center, Nanchang, China
| | - Shiyu Shi
- Department of Rehabilitation, Liyuan Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hongyi Yao
- Department of Rehabilitation, Liyuan Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yisheng Lu
- Department of Physiology, School of Basic Medicine, Huazhong University of Science and Technology, Wuhan, China
| | - Sulin Zhang
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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El-Saied S, Kaminer BM, Kaplan DM, Shitrit R, Manilis I, Amar A, Lewis EC. Trauma-Induced Vestibular Dysfunction: Improved Repair Under Local Treatment With α1-Antitrypsin. Otol Neurotol 2024; 45:818-823. [PMID: 38896787 DOI: 10.1097/mao.0000000000004231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
AIM To characterize vestibular recovery in a mouse model of unilateral labyrinthotomy under local AAT and dexamethasone treatment. BACKGROUND Alpha1-antitrypsin (AAT) is a circulating tissue-protective molecule that rises during inflammatory conditions and promotes inflammatory resolution. Its local concentration in human perilymph inversely correlates with the severity of inner ear dysfunction; concomitantly, mice that overexpress AAT and undergo inner ear trauma rapidly restore vestibular function. Locally applied AAT has yet to be examined in this context, nor has it been directly compared with anti-inflammatory corticosteroid treatment. METHODS Wild-type mice C57BL/6 underwent a unilateral inner ear injury. Nine microliters of saline, clinical-grade AAT (180 μg/site), dexamethasone (4 mg/site), or both were applied locally on Days 0, 1, and 2 (n = 5/group). Vestibular function was assessed for 7 days. An in vitro human epithelial gap closure assay was performed using A549 cells in the presence of AAT and/or dexamethasone. RESULTS Upon labyrinthotomy, all groups displayed severe vestibular dysfunction. Saline-treated mice showed the longest impairment. That group and the dexamethasone group displayed partial to no recovery, while AAT-treated mice exhibited complete recovery within 7 days; at this time point, dexamethasone-treated mice exhibited 50% recovery. Objective vestibular testing showed similar outcomes. In vitro, cotreatment with AAT and dexamethasone resulted in a gap closure dynamic that was superior to AAT alone at 6 h and superior to DEX alone at 48 h. CONCLUSION Locally applied AAT treatment is superior to locally applied dexamethasone in promoting vestibular recovery in vivo. Ongoing studies are exploring the potential advantages of AAT combined with early low-dose dexamethasone therapy.
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Affiliation(s)
- Sabri El-Saied
- Department of Otolaryngology-Head & Neck Surgery, Soroka University Medical Center, Israel
| | - Benyamin M Kaminer
- Department of Otolaryngology-Head & Neck Surgery, Soroka University Medical Center, Israel
| | - Daniel M Kaplan
- Department of Otolaryngology-Head & Neck Surgery, Soroka University Medical Center, Israel
| | - Rivka Shitrit
- Department of Clinical Biochemistry & Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Idan Manilis
- Department of Clinical Biochemistry & Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Amit Amar
- Department of Clinical Biochemistry & Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Eli C Lewis
- Department of Clinical Biochemistry & Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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Wu J, Xu X, Zhang S, Li M, Qiu Y, Lu G, Zheng Z, Huang H. Plastic Events of the Vestibular Nucleus: the Initiation of Central Vestibular Compensation. Mol Neurobiol 2024:10.1007/s12035-024-04208-2. [PMID: 38689145 DOI: 10.1007/s12035-024-04208-2] [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: 05/19/2023] [Accepted: 04/18/2024] [Indexed: 05/02/2024]
Abstract
Vestibular compensation is a physiological response of the vestibular organs within the inner ear. This adaptation manifests during consistent exposure to acceleration or deceleration, with the vestibular organs incrementally adjusting to such changes. The molecular underpinnings of vestibular compensation remain to be fully elucidated, yet emerging studies implicate associations with neuroplasticity and signal transduction pathways. Throughout the compensation process, the vestibular sensory neurons maintain signal transmission to the central equilibrium system, facilitating adaptability through alterations in synaptic transmission and neuronal excitability. Notable molecular candidates implicated in this process include variations in ion channels and neurotransmitter profiles, as well as neuronal and synaptic plasticity, metabolic processes, and electrophysiological modifications. This study consolidates the current understanding of the molecular events in vestibular compensation, augments the existing research landscape, and evaluates contemporary therapeutic strategies. Furthermore, this review posits potential avenues for future research that could enhance our comprehension of vestibular compensation mechanisms.
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Affiliation(s)
- Junyu Wu
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, No.58 Zhongshan Road 2, Guangzhou, 510080, China
| | - Xue Xu
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, No.58 Zhongshan Road 2, Guangzhou, 510080, China
| | - Shifeng Zhang
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, No.58 Zhongshan Road 2, Guangzhou, 510080, China
| | - Minping Li
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, No.58 Zhongshan Road 2, Guangzhou, 510080, China
| | - Yuemin Qiu
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, No.58 Zhongshan Road 2, Guangzhou, 510080, China
| | - Gengxin Lu
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, No.58 Zhongshan Road 2, Guangzhou, 510080, China
| | - Zhihui Zheng
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, No.58 Zhongshan Road 2, Guangzhou, 510080, China
| | - Haiwei Huang
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, No.58 Zhongshan Road 2, Guangzhou, 510080, China.
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Rastoldo G, Tighilet B. The Vestibular Nuclei: A Cerebral Reservoir of Stem Cells Involved in Balance Function in Normal and Pathological Conditions. Int J Mol Sci 2024; 25:1422. [PMID: 38338702 PMCID: PMC10855768 DOI: 10.3390/ijms25031422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 01/18/2024] [Accepted: 01/20/2024] [Indexed: 02/12/2024] Open
Abstract
In this review, we explore the intriguing realm of neurogenesis in the vestibular nuclei-a critical brainstem region governing balance and spatial orientation. We retrace almost 20 years of research into vestibular neurogenesis, from its discovery in the feline model in 2007 to the recent discovery of a vestibular neural stem cell niche. We explore the reasons why neurogenesis is important in the vestibular nuclei and the triggers for activating the vestibular neurogenic niche. We develop the symbiotic relationship between neurogenesis and gliogenesis to promote vestibular compensation. Finally, we examine the potential impact of reactive neurogenesis on vestibular compensation, highlighting its role in restoring balance through various mechanisms.
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Affiliation(s)
- Guillaume Rastoldo
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, 13331 Marseille, France;
| | - Brahim Tighilet
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, 13331 Marseille, France;
- GDR Vertige CNRS Unité GDR2074, 13331 Marseille, France
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Kunelskay NL, Ivanova GE, Baybakova EV, Guseva AL, Parfenov VA, Zamergrad MV, Zaitseva OV, Melnikov OA, Shmonin AA, Maltseva MN. [Vestibular rehabilitation for peripheral vestibular hypofunction: an interdisciplinary consensus]. Vestn Otorinolaringol 2024; 89:52-63. [PMID: 38506027 DOI: 10.17116/otorino20248901152] [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] [Indexed: 03/21/2024]
Abstract
The literature review presents approaches to the management of patients with vestibular disorders. The principles of organization of vestibular rehabilitation in peripheral vestibular hypofunction, indications for appointment, factors influencing its implementation, technique, methods of evaluating effectiveness are considered in detail. Attention is drawn to the fact that the selection of exercises and the duration of vestibular rehabilitation is carried out individually and depends on many factors, including the nature of vestibular deficiency and the specific characteristics of the patient. The possibilities of using additional pharmacological therapy with histamine preparations, which can accelerate the onset of vestibular compensation, are shown. It is noted that vestibular rehabilitation is a safe and effective method of treating peripheral vestibular hypofunction and should be recommended to patients of all ages with vestibular disorders leading to limited social and physical activity.
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Affiliation(s)
- N L Kunelskay
- Sverzhevsky Research Clinical Institute of Otorhinolaryngology, Moscow, Russia
- Pirogov Russian National Research Medical University, Moscow, Russia
| | - G E Ivanova
- Pirogov Russian National Research Medical University, Moscow, Russia
| | - E V Baybakova
- Sverzhevsky Research Clinical Institute of Otorhinolaryngology, Moscow, Russia
| | - A L Guseva
- Pirogov Russian National Research Medical University, Moscow, Russia
- Pirogov Municipal Clinical Hospital No. 1, Moscow, Russia
| | - V A Parfenov
- Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - M V Zamergrad
- Pirogov Russian National Research Medical University, Moscow, Russia
- Russian Medical Academy for Continuous Professional Education, Moscow, Russia
| | - O V Zaitseva
- National Medical Research Center for Otorhinolaryngology of the FMBA of Russia, Moscow, Russia
| | | | - A A Shmonin
- Pavlov First St. Petersburg State Medical University, St. Petersburg, Russia
| | - M N Maltseva
- Pavlov First St. Petersburg State Medical University, St. Petersburg, Russia
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Zaidel A. Multisensory Calibration: A Variety of Slow and Fast Brain Processes Throughout the Lifespan. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1437:139-152. [PMID: 38270858 DOI: 10.1007/978-981-99-7611-9_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
From before we are born, throughout development, adulthood, and aging, we are immersed in a multisensory world. At each of these stages, our sensory cues are constantly changing, due to body, brain, and environmental changes. While integration of information from our different sensory cues improves precision, this only improves accuracy if the underlying cues are unbiased. Thus, multisensory calibration is a vital and ongoing process. To meet this grand challenge, our brains have evolved a variety of mechanisms. First, in response to a systematic discrepancy between sensory cues (without external feedback) the cues calibrate one another (unsupervised calibration). Second, multisensory function is calibrated to external feedback (supervised calibration). These two mechanisms superimpose. While the former likely reflects a lower level mechanism, the latter likely reflects a higher level cognitive mechanism. Indeed, neural correlates of supervised multisensory calibration in monkeys were found in higher level multisensory cortical area VIP, but not in the relatively lower level multisensory area MSTd. In addition, even without a cue discrepancy (e.g., when experiencing stimuli from different sensory cues in series) the brain monitors supra-modal statistics of events in the environment and adapts perception cross-modally. This too comprises a variety of mechanisms, including confirmation bias to prior choices, and lower level cross-sensory adaptation. Further research into the neuronal underpinnings of the broad and diverse functions of multisensory calibration, with improved synthesis of theories is needed to attain a more comprehensive understanding of multisensory brain function.
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Affiliation(s)
- Adam Zaidel
- Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel.
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Tramontano M, Manzari L, Bustos ASO, De Angelis S, Montemurro R, Belluscio V, Bergamini E, Vannozzi G. Instrumental assessment of dynamic postural stability in patients with unilateral vestibular hypofunction during straight, curved, and blindfolded gait. Eur Arch Otorhinolaryngol 2024; 281:83-94. [PMID: 37382626 DOI: 10.1007/s00405-023-08082-x] [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: 03/02/2023] [Accepted: 06/15/2023] [Indexed: 06/30/2023]
Abstract
PURPOSE To characterise dynamic postural stability of gait in patients with vestibular hypofunction (PwVH) using a sensor-based assessment while performing dynamic tasks and to correlate the results of this evaluation with clinical scales. METHODS This cross-sectional study involved 22 adults between 18 and 70 years old from a healthcare hospital centre. Eleven patients suffering from chronic vestibular hypofunction (PwVH) and eleven healthy controls (HC) were evaluated through a combined inertial sensor-based and clinical scale assessment. Participants were equipped with five synchronised inertial measurement units (IMUs) (128 Hz, Opal, APDM, Portland, OR, USA): three IMUs were located on the occipital cranium bone, near the lambdoid suture of the head, at the centre of the sternum, and at L4/L5 level, just above the pelvis, and were used to quantify gait quality parameters, while the other two were located slightly above lateral malleoli and used to perform stride and step segmentation. Three different motor tasks were performed in a randomized order: the 10-m Walk Test (10mWT), the Figure of Eight Walk Test (Fo8WT) and the Fukuda Stepping Test (FST). A set of gait quality parameters related to stability, symmetry and smoothness of gait were extracted from IMU data and correlated with the clinical scale scores. PwVH and HC results were compared to test for significant between-group differences. RESULTS Significant differences were found for the three motor tasks (10mWT, Fo8WT and FST) when comparing PwVH and HC groups. For the 10mWT and the Fo8WT, significant differences between the PwVH and HC groups were found for the stability indexes. Considering the FST, significant differences between the PwVH and HC groups were also found in the stability and symmetry of gait. A significant correlation was found between the Dizziness Handicap Inventory and gait indices during the Fo8WT. CONCLUSIONS In this study, we characterized the dynamic postural stability alterations during linear, curved, and blindfolded walking/stepping in PwVH combining an instrumental IMU-based with traditional clinical scales approach. Combining instrumental and clinical evaluation for dynamic stability of gait alterations in PwVH is useful in thoroughly evaluating the effects of unilateral vestibular hypofunction.
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Affiliation(s)
- M Tramontano
- Fondazione Santa Lucia IRCCS, 00179, Rome, Italy
| | | | - A S Orejel Bustos
- Fondazione Santa Lucia IRCCS, 00179, Rome, Italy
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", 00135, Rome, Italy
| | - S De Angelis
- Fondazione Santa Lucia IRCCS, 00179, Rome, Italy
| | - R Montemurro
- Fondazione Santa Lucia IRCCS, 00179, Rome, Italy
| | - V Belluscio
- Fondazione Santa Lucia IRCCS, 00179, Rome, Italy
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", 00135, Rome, Italy
| | - E Bergamini
- Fondazione Santa Lucia IRCCS, 00179, Rome, Italy
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", 00135, Rome, Italy
| | - G Vannozzi
- Fondazione Santa Lucia IRCCS, 00179, Rome, Italy
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", 00135, Rome, Italy
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Tighilet B, Trico J, Marouane E, Zwergal A, Chabbert C. Histaminergic System and Vestibular Function in Normal and Pathological Conditions. Curr Neuropharmacol 2024; 22:1826-1845. [PMID: 38504566 PMCID: PMC11284731 DOI: 10.2174/1570159x22666240319123151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 09/20/2023] [Accepted: 10/13/2023] [Indexed: 03/21/2024] Open
Abstract
Most neurotransmitter systems are represented in the central and peripheral vestibular system and are thereby involved both in normal vestibular signal processing and the pathophysiology of vestibular disorders. However, there is a special relationship between the vestibular system and the histaminergic system. The purpose of this review is to document how the histaminergic system interferes with normal and pathological vestibular function. In particular, we will discuss neurobiological mechanisms such as neuroinflammation that involve histamine to modulate and allow restoration of balance function in the situation of a vestibular insult. These adaptive mechanisms represent targets of histaminergic pharmacological compounds capable of restoring vestibular function in pathological situations. The clinical use of drugs targeting the histaminergic system in various vestibular disorders is critically discussed.
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Affiliation(s)
- Brahim Tighilet
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Marseille, Groupe de Recherche Vertige (GDR#2074), France
| | - Jessica Trico
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Marseille, Groupe de Recherche Vertige (GDR#2074), France
| | - Emna Marouane
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Marseille, Groupe de Recherche Vertige (GDR#2074), France
- Normandie Université, UNICAEN, INSERM, COMETE, CYCERON, CHU Caen, 14000, Caen, France
| | - Andreas Zwergal
- Department of Neurology, LMU University Hospital, Munich, Germany
- German Center for Vertigo and Balance Disorders, LMU University Hospital, Munich, Germany
| | - Christian Chabbert
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Marseille, Groupe de Recherche Vertige (GDR#2074), France
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Zhang Y, Chu G, Leng Y, Lin X, Zhou H, Lu Y, Liu B. Parvalbumin-positive neurons in the medial vestibular nucleus contribute to vestibular compensation through commissural inhibition. Front Cell Neurosci 2023; 17:1260243. [PMID: 38026699 PMCID: PMC10663245 DOI: 10.3389/fncel.2023.1260243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 10/18/2023] [Indexed: 12/01/2023] Open
Abstract
Background The commissural inhibitory system between the bilateral medial vestibular nucleus (MVN) plays a key role in vestibular compensation. Calcium-binding protein parvalbumin (PV) is expressed in MVN GABAergic neurons. Whether these neurons are involved in vestibular compensation is still unknown. Methods After unilateral labyrinthectomy (UL), we measured the activity of MVN PV neurons by in vivo calcium imaging, and observed the projection of MVN PV neurons by retrograde neural tracing. After regulating PV neurons' activity by chemogenetic technique, the effects on vestibular compensation were evaluated by behavior analysis. Results We found PV expression and the activity of PV neurons in contralateral but not ipsilateral MVN increased 6 h following UL. ErbB4 is required to maintain GABA release for PV neurons, conditional knockout ErbB4 from PV neurons promoted vestibular compensation. Further investigation showed that vestibular compensation could be promoted by chemogenetic inhibition of contralateral MVN or activation of ipsilateral MVN PV neurons. Additional neural tracing study revealed that considerable MVN PV neurons were projecting to the opposite side of MVN, and that activating the ipsilateral MVN PV neurons projecting to contralateral MVN can promote vestibular compensation. Conclusion Contralateral MVN PV neuron activation after UL is detrimental to vestibular compensation, and rebalancing bilateral MVN PV neuron activity can promote vestibular compensation, via commissural inhibition from the ipsilateral MVN PV neurons. Our findings provide a new understanding of vestibular compensation at the neural circuitry level and a novel potential therapeutic target for vestibular disorders.
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Affiliation(s)
- Yuejin Zhang
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Guangpin Chu
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yangming Leng
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xueling Lin
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hong Zhou
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yisheng Lu
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Bo Liu
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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10
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Tighilet B, Chabbert C. Cellular and Molecular Mechanisms of Vestibular Ageing. J Clin Med 2023; 12:5519. [PMID: 37685587 PMCID: PMC10487907 DOI: 10.3390/jcm12175519] [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: 06/29/2023] [Revised: 08/16/2023] [Accepted: 08/22/2023] [Indexed: 09/10/2023] Open
Abstract
While age-related auditory deficits and cochlear alterations are well described, those affecting the vestibular sensory organs and more broadly the central vestibular pathways are much less documented. Although there is inter-individual heterogeneity in the phenomenon of vestibular ageing, common tissue alterations, such as losses of sensory hair cells or primary and secondary neurons during the ageing process, can be noted. In this review, we document the cellular and molecular processes that occur during ageing in the peripheral and central vestibular system and relate them to the impact of age-related vestibular deficits based on current knowledge.
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Affiliation(s)
- Brahim Tighilet
- Aix Marseille University-CNRS, Laboratory of Cognitive Neurosciences, UMR7291, Team Pathophysiology and Therapy of Vestibular Disorders, 13331 Marseille, France
- Research Group on Vestibular Pathophysiology, CNRS, Unit GDR2074, 13331 Marseille, France
| | - Christian Chabbert
- Aix Marseille University-CNRS, Laboratory of Cognitive Neurosciences, UMR7291, Team Pathophysiology and Therapy of Vestibular Disorders, 13331 Marseille, France
- Research Group on Vestibular Pathophysiology, CNRS, Unit GDR2074, 13331 Marseille, France
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Rastoldo G, Tighilet B. Thyroid Axis and Vestibular Physiopathology: From Animal Model to Pathology. Int J Mol Sci 2023; 24:9826. [PMID: 37372973 DOI: 10.3390/ijms24129826] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 06/02/2023] [Accepted: 06/03/2023] [Indexed: 06/29/2023] Open
Abstract
A recent work of our group has shown the significant effects of thyroxine treatment on the restoration of postural balance function in a rodent model of acute peripheral vestibulopathy. Based on these findings, we attempt to shed light in this review on the interaction between the hypothalamic-pituitary-thyroid axis and the vestibular system in normal and pathological situations. Pubmed database and relevant websites were searched from inception through to 4 February 2023. All studies relevant to each subsection of this review have been included. After describing the role of thyroid hormones in the development of the inner ear, we investigated the possible link between the thyroid axis and the vestibular system in normal and pathological conditions. The mechanisms and cellular sites of action of thyroid hormones on animal models of vestibulopathy are postulated and therapeutic options are proposed. In view of their pleiotropic action, thyroid hormones represent a target of choice to promote vestibular compensation at different levels. However, very few studies have investigated the relationship between thyroid hormones and the vestibular system. It seems then important to more extensively investigate the link between the endocrine system and the vestibule in order to better understand the vestibular physiopathology and to find new therapeutic leads.
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Affiliation(s)
- Guillaume Rastoldo
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, 13331 Marseille, France
| | - Brahim Tighilet
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, 13331 Marseille, France
- GDR Vertige CNRS Unité GDR2074, 13331 Marseille, France
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12
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El Mahmoudi N, Laurent C, Péricat D, Watabe I, Lapotre A, Jacob PY, Tonetto A, Tighilet B, Sargolini F. Long-lasting spatial memory deficits and impaired hippocampal plasticity following unilateral vestibular loss. Prog Neurobiol 2023; 223:102403. [PMID: 36821981 DOI: 10.1016/j.pneurobio.2023.102403] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 11/25/2022] [Accepted: 01/04/2023] [Indexed: 02/23/2023]
Abstract
Unilateral vestibular loss (UVL) induces a characteristic vestibular syndrome composed of various posturo-locomotor, oculomotor, vegetative and perceptivo-cognitive symptoms. Functional deficits are progressively recovered over time during vestibular compensation, that is supported by the expression of multiscale plasticity mechanisms. While the dynamic of post-UVL posturo-locomotor and oculomotor deficits is well characterized, the expression over time of the cognitive deficits, and in particular spatial memory deficits, is still debated. In this study we aimed at investigating spatial memory deficits and their recovery in a rat model of unilateral vestibular neurectomy (UVN), using a wide spectrum of behavioral tasks. In parallel, we analyzed markers of hippocampal plasticity involved in learning and memory. Our results indicate the UVN affects all domains of spatial memory, from working memory to reference memory and object-in-place recognition. These deficits are associated with long-lasting impaired plasticity in the ipsilesional hippocampus. These results highlight the crucial role of symmetrical vestibular information in spatial memory and contribute to a better understanding of the cognitive disorders observed in vestibular patients.
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Affiliation(s)
- Nada El Mahmoudi
- Aix-Marseille Université -CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France.
| | - Célia Laurent
- Aix-Marseille Université -CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
| | - David Péricat
- Université de Toulouse Paul Sabatier -CNRS, Institut de pharmacologie et de biologie structurale, Toulouse, France
| | - Isabelle Watabe
- Aix-Marseille Université -CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
| | - Agnès Lapotre
- Aix-Marseille Université -CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
| | - Pierre-Yves Jacob
- Aix-Marseille Université -CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
| | - Alain Tonetto
- Aix Marseille Université-CNRS, Centrale Marseille, FSCM (FR 1739), PRATIM, F-13397 Marseille, France
| | - Brahim Tighilet
- Aix-Marseille Université -CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
| | - Francesca Sargolini
- Aix-Marseille Université -CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France.
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13
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Sabzevar FT, Vautrelle N, Zheng Y, Smith PF. Vestibular modulation of the tail of the rat striatum. Sci Rep 2023; 13:4443. [PMID: 36932124 PMCID: PMC10023713 DOI: 10.1038/s41598-023-31289-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 03/09/2023] [Indexed: 03/19/2023] Open
Abstract
Fragmented and piecemeal evidence from animal and human studies suggests that vestibular information is transmitted to the striatum, a part of the basal ganglia that degenerates in Parkinson's Disease. Nonetheless, surprisingly little is known about the precise effects of activation of the vestibular system on the striatum. Electrophysiological studies have yielded inconsistent results, with many studies reporting only sparse responses to vestibular stimulation in the dorsomedial striatum. In this study, we sought to elucidate the effects of electrical stimulation of the peripheral vestibular system on electrophysiological responses in the tail of the rat striatum, a newly discovered region for sensory input. Rats were anaesthetised with urethane and a bipolar stimulating electrode was placed in the round window in order to activate the peripheral vestibular system. A recording electrode was positioned in the tail of the striatum. Local field potentials (LFPs) were recorded ipsilaterally and contralaterally to the stimulation using a range of current parameters. In order to confirm that the vestibular system was activated, video-oculography was used to monitor vestibular nystagmus. At current amplitudes that evoked vestibular nystagmus, clear triphasic LFPs were evoked in the bilateral tail of the striatum, with the first phase of the waveform exhibiting latencies of less than 22 ms. The LFP amplitude increased with increasing current amplitude (P ≤ 0.0001). In order to exclude the possibility that the LFPs were evoked by the activation of the auditory system, the cochlea was surgically lesioned in some animals. In these animals the LFPs persisted despite the cochlear lesions, which were verified histologically. Overall, the results obtained suggest that there are vestibular projections to the tail of the striatum, which could possibly arise from projections via the vestibular nucleus or cerebellum and the parafasicular nucleus of the thalamus.
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Affiliation(s)
| | - Nico Vautrelle
- Department of Anatomy, School of Biomedical Sciences, and Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Yiwen Zheng
- Department of Pharmacology and Toxicology, University of Otago, Dunedin, New Zealand
- The Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, New Zealand
| | - Paul F Smith
- Department of Pharmacology and Toxicology, University of Otago, Dunedin, New Zealand.
- The Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, New Zealand.
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14
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Oxytocin Disturbs Vestibular Compensation and Modifies Behavioral Strategies in a Rodent Model of Acute Vestibulopathy. Int J Mol Sci 2022; 23:ijms232315262. [PMID: 36499588 PMCID: PMC9738578 DOI: 10.3390/ijms232315262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 11/18/2022] [Accepted: 11/28/2022] [Indexed: 12/11/2022] Open
Abstract
Unilateral inner ear injury is followed by behavioral recovery due to central vestibular compensation. The therapeutic effect of oxytocin (OT) on vestibular compensation was investigated by behavioral testing in a rat model of unilateral vestibular neurectomy (UVN). Animals in the oxytocin group (UVN-OT) exhibited delayed vestibular compensation on the qualitative scale of vestibular deficits and aggravated static postural deficits (bearing surface) compared to animals in the NaCl group (UVN-NaCl). Surprisingly, oxytocin-treated animals adopt a different postural strategy than untreated animals. Instead of shifting their weight to the ipsilesional paws (left front and hind paws), they shift their weight to the front paws (right and left) without modification along the lateral axis. Furthermore, some locomotor strategies of the animals to compensate for the vestibular loss are also altered by oxytocin treatment. UVN-OT animals do not induce an increase in the distance traveled, their mean velocity is lower than that in the control group, and the ipsilesional body rotations do not increase from 7 to 30 days after UVN. This study reveals that oxytocin treatment hinders the restoration of some postural and locomotor deficits while improving others following vestibular lesions. The mechanisms of the action of oxytocin that support these behavioral changes remain to be elucidated.
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15
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Chen Y, Gong X, Ibrahim SIA, Liang H, Zhang J. Convergent innervations of mesencephalic trigeminal and vestibular nuclei neurons onto oculomotor and pre-oculomotor neurons-Tract tracing and triple labeling in rats. PLoS One 2022; 17:e0278205. [PMID: 36441755 PMCID: PMC9704657 DOI: 10.1371/journal.pone.0278205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 11/13/2022] [Indexed: 11/29/2022] Open
Abstract
In studies of vestibulo-ocular reflex (VOR), the horizontal VOR circuit is much clearer than vertical-torsional VOR. The circuit and mechanism of gravity-related vertical-torsional VOR is probably weak. "Somatosensory vestibular interaction" is a known extra source to facilitate VOR, and cervico-ocular reflex is a representative for torsional VOR compensation. Whereas, how the cervical afferents finally reach the oculomotor system is less documented. Actually, when the head tilts, which generates cervico-ocular reflex, not only the neck muscle is activated, but also the jaw muscle is stretched by gravity dragged mandible and/or tissue-muscle connection between the mandible and clavicle. We have previously identified a projection from the jaw muscle afferent mesencephalic trigeminal nucleus (Vme) neurons to oculomotor nuclei (III/IV) and their premotor neurons in interstitial nucleus of Cajal (INC)-a well-known pre-oculomotor center manipulating vertical-torsional eye movements. We hypothesized that these projections may interact with vestibulo-ocular signals during vertical-torsional VOR, because effects of gravity on jaw muscles and bones has been reported. Thus, we injected different anterograde tracers into the Vme and medial vestibular nucleus (MVN)-the subnuclear area particularly harboring excitatory vestibulo-ocular neurons, and immunostained III/IV motoneurons. Retrograde tracer was injected into the III in the same animals after dual anterograde tracers' injections. Under confocal microscope, we observed the Vme and MVN neuronal endings simultaneously terminated onto the same III/IV motoneurons and the same INC pre-oculomotor neurons. We consider that jaw muscle proprioceptive Vme neurons projecting to the III/IV and INC would sense spindle activity if the jaw muscle is stretched by gravity dragged mandible or connection between mandible and clavicle during head rolling. Therefore, the convergent innervation of the Vme and MVN neurons onto the oculomotor and pre-oculomotor nuclei would be a neuroanatomic substrate for interaction of masticatory proprioception with the vestibulo-ocular signals upon the oculomotor system during vertical-torsional VOR.
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Affiliation(s)
- Yongmei Chen
- Department of Central Laboratory, Hubei University of Art and Science Medical Center, Xiangyang City, Hubei, China
- Institute of Neuroscience, Xiangyang Central Hospital, Affiliation of Hubei University of Art and Science, Xiangyang City, Hubei, China
| | - Xinrui Gong
- Institute of Neuroscience, Xiangyang Central Hospital, Affiliation of Hubei University of Art and Science, Xiangyang City, Hubei, China
- Department of Anesthesiology, Xiangyang Central Hospital, Affiliation of Hubei University of Art and Science, Xiangyang City, Hubei, China
- * E-mail: (XG); (JZ)
| | - Shaimaa I. A. Ibrahim
- Institute of Neuroscience, Xiangyang Central Hospital, Affiliation of Hubei University of Art and Science, Xiangyang City, Hubei, China
- Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, OH, United States of America
| | | | - Jingdong Zhang
- Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, OH, United States of America
- Xi’an BRIGHT Eye Hospital, Xi’an, Shaanxi, China
- * E-mail: (XG); (JZ)
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16
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Cerebrocortical activation following unilateral labyrinthectomy in mice characterized by whole-brain clearing: implications for sensory reweighting. Sci Rep 2022; 12:15424. [PMID: 36104440 PMCID: PMC9474865 DOI: 10.1038/s41598-022-19678-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 09/01/2022] [Indexed: 11/21/2022] Open
Abstract
Posture and gait are maintained by sensory inputs from the vestibular, visual, and somatosensory systems and motor outputs. Upon vestibular damage, the visual and/or somatosensory systems functionally substitute by cortical mechanisms called “sensory reweighting”. We investigated the cerebrocortical mechanisms underlying sensory reweighting after unilateral labyrinthectomy (UL) in mice. Arc-dVenus transgenic mice, in which the gene encoding the fluorescent protein dVenus is transcribed under the control of the promoter of the immediate early gene Arc, were used in combination with whole-brain three-dimensional (3D) imaging. Performance on the rotarod was measured as a behavioral correlate of sensory reweighting. Following left UL, all mice showed the head roll-tilt until UL10, indicating the vestibular periphery damage. The rotarod performance worsened in the UL mice from UL1 to UL3, which rapidly recovered. Whole-brain 3D imaging revealed that the number of activated neurons in S1, but not in V1, in UL7 was higher than that in sham-treated mice. At UL7, medial prefrontal cortex (mPFC) and agranular insular cortex (AIC) activation was also observed. Therefore, sensory reweighting to the somatosensory system could compensate for vestibular dysfunction following UL; further, mPFC and AIC contribute to the integration of sensory and motor functions to restore balance.
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17
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Dubois CJ, Cardoit L, Simmers J, Lambert FM, Thoby-Brisson M. Perinatal development of central vestibular neurons in mice. Front Neurosci 2022; 16:935166. [PMID: 36117641 PMCID: PMC9475070 DOI: 10.3389/fnins.2022.935166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 08/10/2022] [Indexed: 11/13/2022] Open
Abstract
Central circuitry of the vestibular nuclei integrates sensory inputs in the adaptive control of motor behaviors such as posture, locomotion, and gaze stabilization. Thus far, such circuits have been mostly examined at mature stages, whereas their emergence and early development have remained poorly described. Here, we focused on the perinatal period of murine development, from embryonic day E14.5 to post-natal day P5, to investigate the ontogeny of two functionally distinct vestibular neuronal groups, neurons projecting to the spinal cord via the lateral vestibulospinal tract (LVST) and commissural neurons of the medial vestibular nucleus that cross the midline to the contralateral nucleus. Using transgenic mice and retrograde labeling, we found that network-constitutive GABAergic and glycinergic neurons are already established in the two vestibular groups at embryonic stages. Although incapable of repetitive firing at E14.5, neurons of both groups can generate spike trains from E15.5 onward and diverge into previously established A or B subtypes according to the absence (A) or presence (B) of a two-stage spike after hyperpolarization. Investigation of several voltage-dependent membrane properties indicated that solely LVST neurons undergo significant maturational changes in their electrophysiological characteristics during perinatal development. The proportions of A vs B subtypes also evolve in both groups, with type A neurons remaining predominant at all stages, and type B commissural neurons appearing only post-natally. Together, our results indicate that vestibular neurons acquire their distinct morpho-functional identities after E14.5 and that the early maturation of membrane properties does not emerge uniformly in the different functional subpopulations of vestibulo-motor pathways.
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18
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Microglial Dynamics Modulate Vestibular Compensation in a Rodent Model of Vestibulopathy and Condition the Expression of Plasticity Mechanisms in the Deafferented Vestibular Nuclei. Cells 2022; 11:cells11172693. [PMID: 36078101 PMCID: PMC9454928 DOI: 10.3390/cells11172693] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 08/17/2022] [Accepted: 08/24/2022] [Indexed: 11/17/2022] Open
Abstract
Unilateral vestibular loss (UVL) induces a vestibular syndrome composed of posturo-locomotor, oculomotor, vegetative, and perceptivo-cognitive symptoms. With time, these functional deficits progressively disappear due to a phenomenon called vestibular compensation, known to be supported by the expression in the deafferented vestibular nuclei (VNs) of various adaptative plasticity mechanisms. UVL is known to induce a neuroinflammatory response within the VNs, thought to be caused by the structural alteration of primary vestibular afferents. The acute inflammatory response, expressed in the deafferented VNs was recently proven to be crucial for the expression of the endogenous plasticity supporting functional recovery. Neuroinflammation is supported by reactive microglial cells, known to have various phenotypes with adverse effects on brain tissue. Here, we used markers of pro-inflammatory and anti-inflammatory phenotypes of reactive microglia to study microglial dynamics following a unilateral vestibular neurectomy (UVN) in the adult rat. In addition, to highlight the role of acute inflammation in vestibular compensation and its underlying mechanisms, we enhanced the inflammatory state of the deafferented VNs using systemic injections of lipopolysaccharide (LPS) during the acute phase after a UVN. We observed that the UVN induced the expression of both M1 proinflammatory and M2 anti-inflammatory microglial phenotypes in the deafferented VNs. The acute LPS treatment exacerbated the inflammatory reaction and increased the M1 phenotype while decreasing M2 expression. These effects were associated with impaired postlesional plasticity in the deafferented VNs and exacerbated functional deficits. These results highlight the importance of a homeostatic inflammatory level in the expression of the adaptative plasticity mechanisms underlying vestibular compensation. Understanding the rules that govern neuroinflammation would provide therapeutic leads in neuropathologies associated with these processes.
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19
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Madhani A, Lewis RF, Karmali F. How Peripheral Vestibular Damage Affects Velocity Storage: a Causative Explanation. J Assoc Res Otolaryngol 2022; 23:551-566. [PMID: 35768706 PMCID: PMC9437187 DOI: 10.1007/s10162-022-00853-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 05/30/2022] [Indexed: 10/17/2022] Open
Abstract
Velocity storage is a centrally-mediated mechanism that processes peripheral vestibular inputs. One prominent aspect of velocity storage is its effect on dynamic responses to yaw rotation. Specifically, when normal human subjects are accelerated to constant angular yaw velocity, horizontal eye movements and perceived angular velocity decay exponentially with a time constant circa 15-30 s, even though the input from the vestibular periphery decays much faster (~ 6 s). Peripheral vestibular damage causes a time constant reduction, which is useful for clinical diagnoses, but a mechanistic explanation for the relationship between vestibular damage and changes in these behavioral dynamics is lacking. It has been hypothesized that Bayesian optimization determines ideal velocity storage dynamics based on statistics of vestibular noise and experienced motion. Specifically, while a longer time constant would make the central estimate of angular head velocity closer to actual head motion, it may also result in the accumulation of neural noise which simultaneously degrades precision. Thus, the brain may balance these two effects by determining the time constant that optimizes behavior. We applied a Bayesian optimal Kalman filter to determine the ideal velocity storage time constant for unilateral damage. Predicted time constants were substantially lower than normal and similar to patients. Building on our past work showing that Bayesian optimization explains age-related changes in velocity storage, we also modeled interactions between age-related hair cell loss and peripheral damage. These results provide a plausible mechanistic explanation for changes in velocity storage after peripheral damage. Results also suggested that even after peripheral damage, noise originating in the periphery or early central processing may remain relevant in neurocomputations. Overall, our findings support the hypothesis that the brain optimizes velocity storage based on the vestibular signal-to-noise ratio.
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Affiliation(s)
- Amsal Madhani
- Jenks Vestibular Physiology Lab, Massachusetts Eye and Ear Infirmary, Boston, MA USA
| | - Richard F. Lewis
- Jenks Vestibular Physiology Lab, Massachusetts Eye and Ear Infirmary, Boston, MA USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA USA
- Department of Neurology, Harvard Medical School, Boston, MA USA
| | - Faisal Karmali
- Jenks Vestibular Physiology Lab, Massachusetts Eye and Ear Infirmary, Boston, MA USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA USA
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20
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Bringuier CM, Hatat B, Boularand R, Chabbert C, Tighilet B. Characterization of Thyroid Hormones Antivertigo Effects in a Rat Model of Excitotoxically-Induced Vestibulopathy. Front Neurol 2022; 13:877319. [PMID: 35693004 PMCID: PMC9175002 DOI: 10.3389/fneur.2022.877319] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 04/12/2022] [Indexed: 11/20/2022] Open
Abstract
Impaired vestibular function induces disabling symptoms such as postural imbalance, impaired locomotion, vestibulo-ocular reflex alteration, impaired cognitive functions such as spatial disorientation, and vegetative deficits. These symptoms show up in sudden attacks in patients with Ménière or neuritis and may lead to emergency hospitalizations. To date, however, there is no curative solution to these pathologies and the effectiveness of treatments used to reduce symptoms in the management of patients is discussed. Thus, elucidating the biological mechanisms correlated to the expression kinetics of the vestibular syndrome is useful for the development of potential therapeutic candidates with a view to relieving patients and limiting emergency hospitalizations. Recently, a robust antivertigo effect of thyroxine (T4) was demonstrated in a rodent model of impaired vestibular function induced by unilateral surgical section of the vestibular nerve. The aim of the present study was to assess thyroid hormones L-T4 and triiodothyronine (T3) as well as the bioactive thyroid hormone metabolite TRIAC on a rodent model of acute unilateral vestibulopathy more representative of clinical vestibular pathology. To this end, a partial and transient unilateral suppression of peripheral vestibular inputs was induced by an excitotoxic lesion caused by transtympanic injection of kainic acid (TTK) into the inner ear of adult rats. Vestibular syndrome and functional recovery were studied by semi-quantitative and quantitative assessments of relevant posturo-locomotor parameters. In contrast to the effect previously demonstrated in the complete and irreversible vestibular injury model, administration of thyroxine in the TTK rodent model did not display significant antivertigo effect. However, it is noteworthy that administration of thyroxine showed trends to prevent posturo-locomotor alterations. Furthermore, the results of the current study suggested that a single dose of thyroxine is sufficient to induce the same effects on vestibular syndrome observed with sub-chronic administration, and that reducing the T4 dose may more efficiently prevent the appearance of vestibular deficits induced by the excitotoxic type lesion. Finally, comparison of the antivertigo effect of T4 in different vestibulopathy models enables us to determine the therapeutic indication in which thyroxine could be a potential therapeutic candidate.
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Affiliation(s)
| | | | | | - Christian Chabbert
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Marseille, France
| | - Brahim Tighilet
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Marseille, France
- *Correspondence: Brahim Tighilet
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21
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Maudoux A, Vitry S, El-Amraoui A. Vestibular Deficits in Deafness: Clinical Presentation, Animal Modeling, and Treatment Solutions. Front Neurol 2022; 13:816534. [PMID: 35444606 PMCID: PMC9013928 DOI: 10.3389/fneur.2022.816534] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 02/23/2022] [Indexed: 11/13/2022] Open
Abstract
The inner ear is responsible for both hearing and balance. These functions are dependent on the correct functioning of mechanosensitive hair cells, which convert sound- and motion-induced stimuli into electrical signals conveyed to the brain. During evolution of the inner ear, the major changes occurred in the hearing organ, whereas the structure of the vestibular organs remained constant in all vertebrates over the same period. Vestibular deficits are highly prevalent in humans, due to multiple intersecting causes: genetics, environmental factors, ototoxic drugs, infections and aging. Studies of deafness genes associated with balance deficits and their corresponding animal models have shed light on the development and function of these two sensory systems. Bilateral vestibular deficits often impair individual postural control, gaze stabilization, locomotion and spatial orientation. The resulting dizziness, vertigo, and/or falls (frequent in elderly populations) greatly affect patient quality of life. In the absence of treatment, prosthetic devices, such as vestibular implants, providing information about the direction, amplitude and velocity of body movements, are being developed and have given promising results in animal models and humans. Novel methods and techniques have led to major progress in gene therapies targeting the inner ear (gene supplementation and gene editing), 3D inner ear organoids and reprograming protocols for generating hair cell-like cells. These rapid advances in multiscale approaches covering basic research, clinical diagnostics and therapies are fostering interdisciplinary research to develop personalized treatments for vestibular disorders.
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Affiliation(s)
- Audrey Maudoux
- Unit Progressive Sensory Disorders, Pathophysiology and Therapy, Institut Pasteur, Institut de l'Audition, Université de Paris, INSERM-UMRS1120, Paris, France
- Center for Balance Evaluation in Children (EFEE), Otolaryngology Department, Assistance Publique des Hôpitaux de Paris, Robert-Debré University Hospital, Paris, France
| | - Sandrine Vitry
- Unit Progressive Sensory Disorders, Pathophysiology and Therapy, Institut Pasteur, Institut de l'Audition, Université de Paris, INSERM-UMRS1120, Paris, France
| | - Aziz El-Amraoui
- Unit Progressive Sensory Disorders, Pathophysiology and Therapy, Institut Pasteur, Institut de l'Audition, Université de Paris, INSERM-UMRS1120, Paris, France
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22
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Nguyen TT, Nam GS, Han GC, Le C, Oh SY. The Effect of Galvanic Vestibular Stimulation on Visuospatial Cognition in an Incomplete Bilateral Vestibular Deafferentation Mouse Model. Front Neurol 2022; 13:857736. [PMID: 35370874 PMCID: PMC8971559 DOI: 10.3389/fneur.2022.857736] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 02/15/2022] [Indexed: 11/13/2022] Open
Abstract
ObjectivesTo evaluate the efficacy of galvanic vestibular stimulation (GVS) for recovering from the locomotor and spatial memory deficits of a murine bilateral vestibular deafferentation (BVD) model.MethodsMale C57BL/6 mice (n = 36) were assigned to three groups: bilateral labyrinthectomy with (BVD_GVS group) and without (BVD_non-GVS group) the GVS intervention, and a control group with the sham operation. We used the open field and Y maze, and Morris water maze (MWM) tests to assess locomotor and visuospatial cognitive performance before (baseline) and 3, 7, and 14 days after surgical bilateral labyrinthectomy. For the GVS group, a sinusoidal current at the frequency at 1 Hz and amplitude 0.1 mA was delivered for 30 min daily from the postoperative day (POD) 0 to 4 via electrodes inserted subcutaneously close to both the bony labyrinths.ResultsShort-term spatial memory was significantly impaired in bilaterally labyrinthectomized mice (BVD_non-GVS group), as reflected by decreased spontaneous alternation performance in the place recognition test and time spent in the novel arm and increased same arm return in the Y-maze test, compared with the control. Long-term spatial memory was also impaired, as indicated by a longer escape latency in the hidden platform trial and a lower percentage of time spent in the target quadrant in the probe trial of the MWM. GVS application significantly accelerated the recovery of locomotion and short-term and long-term spatial memory deficits in the BVD mice.ConclusionsOur data demonstrate that locomotion, short-term, and long-term (at least 2 weeks) spatial memory were impaired in BVD mice. The early administration of sinusoidal GVS accelerated the recovery of those locomotion and spatial memory deficiencies. GVS could be applied to patients with BVD to improve their locomotion and vestibular cognitive functioning.
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Affiliation(s)
- Thanh Tin Nguyen
- Jeonbuk National University College of Medicine, Jeonju, South Korea
- Department of Neurology, Jeonbuk National University Hospital and School of Medicine, Jeonju, South Korea
- Department of Pharmacology, Hue University of Medicine and Pharmacy, Hue University, Hue, Vietnam
| | - Gi-Sung Nam
- Department of Neurology, Jeonbuk National University Hospital and School of Medicine, Jeonju, South Korea
- Department of Otorhinolaryngology-Head and Neck Surgery, Chosun University College of Medicine, Gwangju, South Korea
| | - Gyu Cheol Han
- Department of Otolaryngology-Head and Neck Surgery, Gachon University of Medicine and Science, Graduate School of Medicine, Incheon, South Korea
| | - Chuyen Le
- Department of Pharmacology, Hue University of Medicine and Pharmacy, Hue University, Hue, Vietnam
- Department of General-Endocrinology and Internal Medicine, Hue University Hospital, Hue, Vietnam
- *Correspondence: Chuyen Le ;
| | - Sun-Young Oh
- Jeonbuk National University College of Medicine, Jeonju, South Korea
- Department of Neurology, Jeonbuk National University Hospital and School of Medicine, Jeonju, South Korea
- Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju, South Korea
- Sun-Young Oh
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Ibitoye RT, Mallas EJ, Bourke NJ, Kaski D, Bronstein AM, Sharp DJ. The human vestibular cortex: functional anatomy of OP2, its connectivity and the effect of vestibular disease. Cereb Cortex 2022; 33:567-582. [PMID: 35235642 PMCID: PMC9890474 DOI: 10.1093/cercor/bhac085] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 01/31/2022] [Accepted: 02/01/2022] [Indexed: 02/04/2023] Open
Abstract
Area OP2 in the posterior peri-sylvian cortex has been proposed to be the core human vestibular cortex. We investigated the functional anatomy of OP2 and adjacent areas (OP2+) using spatially constrained independent component analysis (ICA) of functional magnetic resonance imaging (fMRI) data from the Human Connectome Project. Ten ICA-derived subregions were identified. OP2+ responses to vestibular and visual motion were analyzed in 17 controls and 17 right-sided vestibular neuritis patients who had previously undergone caloric and optokinetic stimulation during fMRI. In controls, a posterior part of right OP2+ showed: (i) direction-selective responses to visual motion and (ii) activation during caloric stimulation that correlated positively with perceived self-motion, and negatively with visual dependence and peak slow-phase nystagmus velocity. Patients showed abnormal OP2+ activity, with an absence of visual or caloric activation of the healthy ear and no correlations with vertigo or visual dependence-despite normal slow-phase nystagmus responses to caloric stimulation. Activity in a lateral part of right OP2+ correlated with chronic visually induced dizziness in patients. In summary, distinct functional subregions of right OP2+ show strong connectivity to other vestibular areas and a profile of caloric and visual responses, suggesting a central role for vestibular function in health and disease.
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Affiliation(s)
- Richard T Ibitoye
- Computational, Cognitive and Clinical Neuroimaging Laboratory, Department of Brain Sciences, Imperial College London, London W12 0NN, United Kingdom,Neuro-otology Unit, Department of Brain Sciences, Imperial College London, London W6 8RP, United Kingdom
| | - Emma-Jane Mallas
- Computational, Cognitive and Clinical Neuroimaging Laboratory, Department of Brain Sciences, Imperial College London, London W12 0NN, United Kingdom,UK Dementia Research Institute, Care Research & Technology Centre, Imperial College London, London W12 0BZ, United Kingdom
| | - Niall J Bourke
- Computational, Cognitive and Clinical Neuroimaging Laboratory, Department of Brain Sciences, Imperial College London, London W12 0NN, United Kingdom
| | - Diego Kaski
- Department of Clinical and Motor Neurosciences, Centre for Vestibular and Behavioural Neurosciences, University College London, London WC1N 3BG, United Kingdom
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L-Thyroxine Improves Vestibular Compensation in a Rat Model of Acute Peripheral Vestibulopathy: Cellular and Behavioral Aspects. Cells 2022; 11:cells11040684. [PMID: 35203333 PMCID: PMC8869897 DOI: 10.3390/cells11040684] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Revised: 02/08/2022] [Accepted: 02/10/2022] [Indexed: 02/07/2023] Open
Abstract
Unilateral vestibular lesions induce a vestibular syndrome, which recovers over time due to vestibular compensation. The therapeutic effect of L-Thyroxine (L-T4) on vestibular compensation was investigated by behavioral testing and immunohistochemical analysis in a rat model of unilateral vestibular neurectomy (UVN). We demonstrated that a short-term L-T4 treatment reduced the vestibular syndrome and significantly promoted vestibular compensation. Thyroid hormone receptors (TRα and TRβ) and type II iodothyronine deiodinase (DIO2) were present in the vestibular nuclei (VN), supporting a local action of L-T4. We confirmed the T4-induced metabolic effects by demonstrating an increase in the number of cytochrome oxidase-labeled neurons in the VN three days after the lesion. L-T4 treatment modulated glial reaction by decreasing both microglia and oligodendrocytes in the deafferented VN three days after UVN and increased cell proliferation. Survival of newly generated cells in the deafferented vestibular nuclei was not affected, but microglial rather than neuronal differentiation was favored by L-T4 treatment.
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25
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Vestibular Rehabilitation for Peripheral Vestibular Hypofunction: An Updated Clinical Practice Guideline From the Academy of Neurologic Physical Therapy of the American Physical Therapy Association. J Neurol Phys Ther 2021; 46:118-177. [PMID: 34864777 PMCID: PMC8920012 DOI: 10.1097/npt.0000000000000382] [Citation(s) in RCA: 91] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Background: Uncompensated vestibular hypofunction can result in symptoms of dizziness, imbalance, and/or oscillopsia, gaze and gait instability, and impaired navigation and spatial orientation; thus, may negatively impact an individual's quality of life, ability to perform activities of daily living, drive, and work. It is estimated that one-third of adults in the United States have vestibular dysfunction and the incidence increases with age. There is strong evidence supporting vestibular physical therapy for reducing symptoms, improving gaze and postural stability, and improving function in individuals with vestibular hypofunction. The purpose of this revised clinical practice guideline is to improve quality of care and outcomes for individuals with acute, subacute, and chronic unilateral and bilateral vestibular hypofunction by providing evidence-based recommendations regarding appropriate exercises. Methods: These guidelines are a revision of the 2016 guidelines and involved a systematic review of the literature published since 2015 through June 2020 across 6 databases. Article types included meta-analyses, systematic reviews, randomized controlled trials, cohort studies, case-control series, and case series for human subjects, published in English. Sixty-seven articles were identified as relevant to this clinical practice guideline and critically appraised for level of evidence. Results: Based on strong evidence, clinicians should offer vestibular rehabilitation to adults with unilateral and bilateral vestibular hypofunction who present with impairments, activity limitations, and participation restrictions related to the vestibular deficit. Based on strong evidence and a preponderance of harm over benefit, clinicians should not include voluntary saccadic or smooth-pursuit eye movements in isolation (ie, without head movement) to promote gaze stability. Based on moderate to strong evidence, clinicians may offer specific exercise techniques to target identified activity limitations and participation restrictions, including virtual reality or augmented sensory feedback. Based on strong evidence and in consideration of patient preference, clinicians should offer supervised vestibular rehabilitation. Based on moderate to weak evidence, clinicians may prescribe weekly clinic visits plus a home exercise program of gaze stabilization exercises consisting of a minimum of: (1) 3 times per day for a total of at least 12 minutes daily for individuals with acute/subacute unilateral vestibular hypofunction; (2) 3 to 5 times per day for a total of at least 20 minutes daily for 4 to 6 weeks for individuals with chronic unilateral vestibular hypofunction; (3) 3 to 5 times per day for a total of 20 to 40 minutes daily for approximately 5 to 7 weeks for individuals with bilateral vestibular hypofunction. Based on moderate evidence, clinicians may prescribe static and dynamic balance exercises for a minimum of 20 minutes daily for at least 4 to 6 weeks for individuals with chronic unilateral vestibular hypofunction and, based on expert opinion, for a minimum of 6 to 9 weeks for individuals with bilateral vestibular hypofunction. Based on moderate evidence, clinicians may use achievement of primary goals, resolution of symptoms, normalized balance and vestibular function, or plateau in progress as reasons for stopping therapy. Based on moderate to strong evidence, clinicians may evaluate factors, including time from onset of symptoms, comorbidities, cognitive function, and use of medication that could modify rehabilitation outcomes. Discussion: Recent evidence supports the original recommendations from the 2016 guidelines. There is strong evidence that vestibular physical therapy provides a clear and substantial benefit to individuals with unilateral and bilateral vestibular hypofunction. Limitations: The focus of the guideline was on peripheral vestibular hypofunction; thus, the recommendations of the guideline may not apply to individuals with central vestibular disorders. One criterion for study inclusion was that vestibular hypofunction was determined based on objective vestibular function tests. This guideline may not apply to individuals who report symptoms of dizziness, imbalance, and/or oscillopsia without a diagnosis of vestibular hypofunction. Disclaimer: These recommendations are intended as a guide to optimize rehabilitation outcomes for individuals undergoing vestibular physical therapy. The contents of this guideline were developed with support from the American Physical Therapy Association and the Academy of Neurologic Physical Therapy using a rigorous review process. The authors declared no conflict of interest and maintained editorial independence. Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A369).
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Marouane E, El Mahmoudi N, Rastoldo G, Péricat D, Watabe I, Lapôtre A, Tonetto A, Xavier F, Dumas O, Chabbert C, Artzner V, Tighilet B. Sensorimotor Rehabilitation Promotes Vestibular Compensation in a Rodent Model of Acute Peripheral Vestibulopathy by Promoting Microgliogenesis in the Deafferented Vestibular Nuclei. Cells 2021; 10:3377. [PMID: 34943885 PMCID: PMC8699190 DOI: 10.3390/cells10123377] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 11/26/2021] [Accepted: 11/29/2021] [Indexed: 12/16/2022] Open
Abstract
Acute peripheral vestibulopathy leads to a cascade of symptoms involving balance and gait disorders that are particularly disabling for vestibular patients. Vestibular rehabilitation protocols have proven to be effective in improving vestibular compensation in clinical practice. Yet, the underlying neurobiological correlates remain unknown. The aim of this study was to highlight the behavioural and cellular consequences of a vestibular rehabilitation protocol adapted to a rat model of unilateral vestibular neurectomy. We developed a progressive sensory-motor rehabilitation task, and the behavioural consequences were quantified using a weight-distribution device. This analysis method provides a precise and ecological analysis of posturolocomotor vestibular deficits. At the cellular level, we focused on the analysis of plasticity mechanisms expressed in the vestibular nuclei. The results obtained show that vestibular rehabilitation induces a faster recovery of posturolocomotor deficits during vestibular compensation associated with a decrease in neurogenesis and an increase in microgliogenesis in the deafferented medial vestibular nucleus. This study reveals for the first time a part of the underlying adaptative neuroplasticity mechanisms of vestibular rehabilitation. These original data incite further investigation of the impact of rehabilitation on animal models of vestibulopathy. This new line of research should improve the management of vestibular patients.
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Affiliation(s)
- Emna Marouane
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint-Charles Case C, 3 Place Victor Hugo, CEDEX 03, 13331 Marseille, France; (E.M.); (N.E.M.); (G.R.); (I.W.); (A.L.); (F.X.); (C.C.)
- BIOSEB ALLCAT Instruments, Couperigne, 13127 Vitrolles, France;
| | - Nada El Mahmoudi
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint-Charles Case C, 3 Place Victor Hugo, CEDEX 03, 13331 Marseille, France; (E.M.); (N.E.M.); (G.R.); (I.W.); (A.L.); (F.X.); (C.C.)
| | - Guillaume Rastoldo
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint-Charles Case C, 3 Place Victor Hugo, CEDEX 03, 13331 Marseille, France; (E.M.); (N.E.M.); (G.R.); (I.W.); (A.L.); (F.X.); (C.C.)
| | - David Péricat
- Institute of Pharmacology and Structural Biology (IPBS), University of Toulouse, CNRS, 31400 Toulouse, France;
| | - Isabelle Watabe
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint-Charles Case C, 3 Place Victor Hugo, CEDEX 03, 13331 Marseille, France; (E.M.); (N.E.M.); (G.R.); (I.W.); (A.L.); (F.X.); (C.C.)
| | - Agnès Lapôtre
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint-Charles Case C, 3 Place Victor Hugo, CEDEX 03, 13331 Marseille, France; (E.M.); (N.E.M.); (G.R.); (I.W.); (A.L.); (F.X.); (C.C.)
| | - Alain Tonetto
- Fédération de Recherche Sciences Chimiques Marseille FR 1739, Pôle 18 PRATIM, CEDEX 03, 13331 Marseille, France;
| | - Frédéric Xavier
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint-Charles Case C, 3 Place Victor Hugo, CEDEX 03, 13331 Marseille, France; (E.M.); (N.E.M.); (G.R.); (I.W.); (A.L.); (F.X.); (C.C.)
- GDR Physiopathologie Vestibulaire—Unité GDR2074, CNRS, 13003 Marseille, France;
| | - Olivier Dumas
- GDR Physiopathologie Vestibulaire—Unité GDR2074, CNRS, 13003 Marseille, France;
| | - Christian Chabbert
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint-Charles Case C, 3 Place Victor Hugo, CEDEX 03, 13331 Marseille, France; (E.M.); (N.E.M.); (G.R.); (I.W.); (A.L.); (F.X.); (C.C.)
- GDR Physiopathologie Vestibulaire—Unité GDR2074, CNRS, 13003 Marseille, France;
| | - Vincent Artzner
- BIOSEB ALLCAT Instruments, Couperigne, 13127 Vitrolles, France;
| | - Brahim Tighilet
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint-Charles Case C, 3 Place Victor Hugo, CEDEX 03, 13331 Marseille, France; (E.M.); (N.E.M.); (G.R.); (I.W.); (A.L.); (F.X.); (C.C.)
- GDR Physiopathologie Vestibulaire—Unité GDR2074, CNRS, 13003 Marseille, France;
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Gordy C, Straka H. Vestibular Influence on Vertebrate Skeletal Symmetry and Body Shape. Front Syst Neurosci 2021; 15:753207. [PMID: 34690711 PMCID: PMC8526847 DOI: 10.3389/fnsys.2021.753207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 09/17/2021] [Indexed: 11/15/2022] Open
Abstract
Vestibular endorgans in the vertebrate inner ear form the principal sensors for head orientation and motion in space. Following the evolutionary appearance of these organs in pre-vertebrate ancestors, specific sensory epithelial patches, such as the utricle, which is sensitive to linear acceleration and orientation of the head with respect to earth’s gravity, have become particularly important for constant postural stabilization. This influence operates through descending neuronal populations with evolutionarily conserved hindbrain origins that directly and indirectly control spinal motoneurons of axial and limb muscles. During embryogenesis and early post-embryonic periods, bilateral otolith signals contribute to the formation of symmetric skeletal elements through a balanced activation of axial muscles. This role has been validated by removal of otolith signals on one side during a specific developmental period in Xenopus laevis tadpoles. This intervention causes severe scoliotic deformations that remain permanent and extend into adulthood. Accordingly, the functional influence of weight-bearing otoconia, likely on utricular hair cells and resultant afferent discharge, represents a mechanism to ensure a symmetric muscle tonus essential for establishing a normal body shape. Such an impact is presumably occurring within a critical period that is curtailed by the functional completion of central vestibulo-motor circuits and by the modifiability of skeletal elements before ossification of the bones. Thus, bilateral otolith organs and their associated sensitivity to head orientation and linear accelerations are not only indispensable for real time postural stabilization during motion in space but also serve as a guidance for the ontogenetic establishment of a symmetric body.
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Affiliation(s)
- Clayton Gordy
- Department Biology II, Ludwig-Maximilians-University Munich, Munich, Germany.,Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Hans Straka
- Department Biology II, Ludwig-Maximilians-University Munich, Munich, Germany
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28
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Tighilet B. [Vestibular compensation and aging: An example of cellular and behavioral resilience over time]. Med Sci (Paris) 2021; 37:851-862. [PMID: 34647873 DOI: 10.1051/medsci/2021144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The vestibular system has a remarkable capacity of self-repair. Vestibular compensation, a model of post-lesional plasticity of the central nervous system, refers to a set of endogenous neuroplasticity mechanisms in the vestibular nuclei in response to damage to the peripheral vestibular system, and underlying functional recovery. During aging, this "homeostatic" plasticity, although still present, diminishes and is accompanied by sensorimotor and cognitive disturbances. Regardless of age, vestibular compensation can be improved by pharmacological therapy but also by rehabilitation based on strengthening other sensory modalities such as visual and proprioceptive modalities, but also cognitive and motor components. In this article, we will first discuss neurobiological mechanisms of vestibular compensation, then document the impact of aging on this adaptive plasticity.
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Affiliation(s)
- Brahim Tighilet
- Aix Marseille Université-CNRS UMR 7291, laboratoire de neurosciences cognitives, équipe physiopathologie et thérapie des désordres vestibulaires, groupe de recherche Vertige (GDR#2074), 3 place Victor Hugo, 13000 Marseille, France
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Nam GS, Nguyen TT, Kang JJ, Han GC, Oh SY. Effects of Galvanic Vestibular Stimulation on Vestibular Compensation in Unilaterally Labyrinthectomized Mice. Front Neurol 2021; 12:736849. [PMID: 34539564 PMCID: PMC8446527 DOI: 10.3389/fneur.2021.736849] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 08/02/2021] [Indexed: 12/01/2022] Open
Abstract
Objectives: To investigate the ameliorating effects of sinusoidal galvanic vestibular stimulation (GVS) on vestibular compensation from unilateral vestibular deafferentation (UVD) using a mouse model of unilateral labyrinthectomy (UL). Methods: Sixteen male C57BL/6 mice were allocated into two groups that comprise UL groups with GVS (GVS group, n = 9) and without GVS intervention (non-GVS group, n = 7). In the experimental groups, we assessed vestibulo-ocular reflex (VOR) recovery before (baseline) and at 3, 7, and 14 days after surgical unilateral labyrinthectomy. In the GVS group, stimulation was applied for 30 min daily from postoperative days (PODs) 0–4 via electrodes inserted subcutaneously next to both bony labyrinths. Results: Locomotion and VOR were significantly impaired in the non-GVS group compared to baseline. The mean VOR gain of the non-GVS group was attenuated to 0.23 at POD 3 and recovered continuously to the value of 0.54 at POD 14, but did not reach the baseline values at any frequency. GVS intervention significantly accelerated recovery of locomotion, as assessed by the amount of circling and total path length in the open field tasks compared to the non-GVS groups on PODs 3 (p < 0.001 in both amount of circling and total path length) and 7 (p < 0.01 in amount of circling and p < 0.001 in total path length, Mann–Whitney U-test). GVS also significantly improved VOR gain compared to the non-GVS groups at PODs 3 (p < 0.001), 7 (p < 0.001), and 14 (p < 0.001, independent t-tests) during sinusoidal rotations. In addition, the recovery of the phase responses and asymmetry of the VOR was significantly better in the GVS group than in the non-GVS group until 2 weeks after UVD (phase, p = 0.001; symmetry, p < 0.001 at POD 14). Conclusion: Recoveries for UVD-induced locomotion and VOR deficits were accelerated by an early intervention with GVS, which implies that GVS has the potential to improve vestibular compensation in patients with acute unilateral vestibular failure.
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Affiliation(s)
- Gi-Sung Nam
- Jeonbuk National University College of Medicine, Jeonju, South Korea.,Department of Otorhinolaryngology-Head and Neck Surgery, Chosun University College of Medicine, Gwangju, South Korea
| | - Thanh Tin Nguyen
- Jeonbuk National University College of Medicine, Jeonju, South Korea.,Department of Neurology, Jeonbuk National University Hospital & School of Medicine, Jeonju, South Korea.,Department of Pharmacology, Hue University of Medicine and Pharmacy, Hue University, Hue, Vietnam
| | - Jin-Ju Kang
- Jeonbuk National University College of Medicine, Jeonju, South Korea.,Department of Neurology, Jeonbuk National University Hospital & School of Medicine, Jeonju, South Korea.,Research Institute of Clinical Medicine of Jeonbuk National University-Jeonbuk National University Hospital, Jeonju, South Korea
| | - Gyu Cheol Han
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Gachon University of Medicine and Science, Incheon, South Korea
| | - Sun-Young Oh
- Jeonbuk National University College of Medicine, Jeonju, South Korea.,Department of Neurology, Jeonbuk National University Hospital & School of Medicine, Jeonju, South Korea.,Research Institute of Clinical Medicine of Jeonbuk National University-Jeonbuk National University Hospital, Jeonju, South Korea
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30
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El Mahmoudi N, Rastoldo G, Marouane E, Péricat D, Watabe I, Tonetto A, Hautefort C, Chabbert C, Sargolini F, Tighilet B. Breaking a dogma: acute anti-inflammatory treatment alters both post-lesional functional recovery and endogenous adaptive plasticity mechanisms in a rodent model of acute peripheral vestibulopathy. J Neuroinflammation 2021; 18:183. [PMID: 34419105 PMCID: PMC8380392 DOI: 10.1186/s12974-021-02222-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 07/19/2021] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Due to their anti-inflammatory action, corticosteroids are the reference treatment for brain injuries and many inflammatory diseases. However, the benefits of acute corticotherapy are now being questioned, particularly in the case of acute peripheral vestibulopathies (APV), characterized by a vestibular syndrome composed of sustained spinning vertigo, spontaneous ocular nystagmus and oscillopsia, perceptual-cognitive, posturo-locomotor, and vegetative disorders. We assessed the effectiveness of acute corticotherapy, and the functional role of acute inflammation observed after sudden unilateral vestibular loss. METHODS We used the rodent model of unilateral vestibular neurectomy, mimicking the syndrome observed in patients with APV. We treated the animals during the acute phase of the vestibular syndrome, either with placebo or methylprednisolone, an anti-inflammatory corticosteroid. At the cellular level, impacts of methylprednisolone on endogenous plasticity mechanisms were assessed through analysis of cell proliferation and survival, glial reactions, neuron's membrane excitability, and stress marker. At the behavioral level, vestibular and posturo-locomotor functions' recovery were assessed with appropriate qualitative and quantitative evaluations. RESULTS We observed that acute treatment with methylprednisolone significantly decreases glial reactions, cell proliferation and survival. In addition, stress and excitability markers were significantly impacted by the treatment. Besides, vestibular syndrome's intensity was enhanced, and vestibular compensation delayed under acute methylprednisolone treatment. CONCLUSIONS We show here, for the first time, that acute anti-inflammatory treatment alters the expression of the adaptive plasticity mechanisms in the deafferented vestibular nuclei and generates enhanced and prolonged vestibular and postural deficits. These results strongly suggest a beneficial role for acute endogenous neuroinflammation in vestibular compensation. They open the way to a change in dogma for the treatment and therapeutic management of vestibular patients.
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Affiliation(s)
- Nada El Mahmoudi
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
- Centre Saint-Charles, Aix-Marseille Université CNRS, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
| | - Guillaume Rastoldo
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
- Centre Saint-Charles, Aix-Marseille Université CNRS, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
| | - Emna Marouane
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
- Centre Saint-Charles, Aix-Marseille Université CNRS, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
| | - David Péricat
- Institut de Pharmacologie Et de Biologie Structurale, Université de Toulouse Paul Sabatier-CNRS, Toulouse, France
| | - Isabelle Watabe
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
- Centre Saint-Charles, Aix-Marseille Université CNRS, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
| | - Alain Tonetto
- Centrale Marseille, FSCM (FR 1739), PRATIM, Aix Marseille Université-CNRS, 13397, Marseille, France
| | - Charlotte Hautefort
- Department of Head and Neck Surgery, Lariboisière University Hospital, Paris, France
| | - Christian Chabbert
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
- Centre Saint-Charles, Aix-Marseille Université CNRS, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
- GDR Physiopathologie Vestibulaire-Unité GDR2074 CNRS, Marseille, France
| | - Francesca Sargolini
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France
| | - Brahim Tighilet
- Aix-Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives, LNC UMR 7291, Centre Saint Charles, Case C; 3 Place Victor Hugo, 13331, Marseille Cedex 03, France.
- GDR Physiopathologie Vestibulaire-Unité GDR2074 CNRS, Marseille, France.
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Nguyen TT, Nam GS, Kang JJ, Han GC, Kim JS, Dieterich M, Oh SY. Galvanic Vestibular Stimulation Improves Spatial Cognition After Unilateral Labyrinthectomy in Mice. Front Neurol 2021; 12:716795. [PMID: 34393985 PMCID: PMC8358680 DOI: 10.3389/fneur.2021.716795] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 06/29/2021] [Indexed: 11/18/2022] Open
Abstract
Objectives: To investigate the deficits of spatial memory and navigation from unilateral vestibular deafferentation (UVD) and to determine the efficacy of galvanic vestibular stimulation (GVS) for recovery from these deficits using a mouse model of unilateral labyrinthectomy (UL). Methods: Thirty-six male C57BL/6 mice were allocated into three groups that comprise a control group and two experimental groups, UVD with (GVS group) and without GVS intervention (non-GVS group). In the experimental groups, we assessed the locomotor and cognitive behavioral function before (baseline) and 3, 7, and 14 days after surgical UL, using the open field (OF), Y maze, and Morris water maze (MWM) tests. In the GVS group, the stimulations were applied for 30 min daily from postoperative day (POD) 0–4 via the electrodes inserted subcutaneously close to both bony labyrinths. Results: Locomotion and spatial cognition were significantly impaired in the mice with UVD non-GVS group compared to the control group. GVS significantly accelerated recovery of locomotion compared to the control and non-GVS groups on PODs 3 (p < 0.001) and 7 (p < 0.05, Kruskal–Wallis and Mann–Whitney U tests) in the OF and Y maze tests. The mice in the GVS group were better in spatial working memory assessed with spontaneous alternation performance and spatial reference memory assessed with place recognition during the Y maze test than those in the non-GVS group on POD 3 (p < 0.001). In addition, the recovery of long-term spatial navigation deficits during the MWM, as indicated by the escape latency and the probe trial, was significantly better in the GVS group than in the non-GVS group 2 weeks after UVD (p < 0.01). Conclusions: UVD impairs spatial memory, navigation, and motor coordination. GVS accelerated recoveries in short- and long-term spatial memory and navigation, as well as locomotor function in mice with UVD, and may be applied to the patients with acute unilateral vestibular failure.
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Affiliation(s)
- Thanh Tin Nguyen
- Jeonbuk National University College of Medicine, Jeonju, South Korea.,Department of Neurology, Jeonbuk National University Hospital & School of Medicine, Jeonju, South Korea.,Department of Pharmacology, Hue University of Medicine and Pharmacy, Hue University, Hue, Vietnam
| | - Gi-Sung Nam
- Department of Neurology, Jeonbuk National University Hospital & School of Medicine, Jeonju, South Korea.,Department of Otorhinolaryngology-Head and Neck Surgery, Chosun University College of Medicine, Kwangju, South Korea
| | - Jin-Ju Kang
- Department of Neurology, Jeonbuk National University Hospital & School of Medicine, Jeonju, South Korea.,Research Institute of Clinical Medicine of Jeonbuk National University-Jeonbuk National University Hospital, Jeonju, South Korea
| | - Gyu Cheol Han
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Gachon University of Medicine and Science, Incheon, South Korea
| | - Ji-Soo Kim
- Department of Neurology, Seoul National University Hospital & School of Medicine, Seoul, South Korea
| | - Marianne Dieterich
- Department of Neurology, University Hospital, Ludwig-Maximilians-Universität, Munich, Germany.,German Center for Vertigo and Balance Disorders-IFB, University Hospital, Ludwig-Maximilians-Universität, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Sun-Young Oh
- Jeonbuk National University College of Medicine, Jeonju, South Korea.,Department of Neurology, Jeonbuk National University Hospital & School of Medicine, Jeonju, South Korea.,Research Institute of Clinical Medicine of Jeonbuk National University-Jeonbuk National University Hospital, Jeonju, South Korea
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32
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Neural Interruption by Unilateral Labyrinthectomy Biases the Directional Preference of Otolith-Related Vestibular Neurons. Brain Sci 2021; 11:brainsci11080987. [PMID: 34439606 PMCID: PMC8393366 DOI: 10.3390/brainsci11080987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/13/2021] [Accepted: 07/22/2021] [Indexed: 11/17/2022] Open
Abstract
Background: The directional preference of otolith-related vestibular neurons elucidates the neuroanatomical link of labyrinths, but few direct experimental data have been provided. Methods: The directional preference of otolith-related vestibular neurons was measured in the vestibular nucleus using chemically induced unilateral labyrinthectomy (UL). For the model evaluation, static and dynamic behavioral tests as well as a histological test were performed. Extracellular neural activity was recorded for the neuronal responses to the horizontal head rotation and the linear head translation. Results: Seventy-seven neuronal activities were recorded, and the total population was divided into three groups: left UL (20), sham (35), and right UL (22). Based on directional preference, two sub-groups were again classified as contra- and ipsi-preferred neurons. There was no significance in the number of those sub-groups (contra-, 15/35, 43%; ipsi-, 20/35, 57%) in the sham (p = 0.155). However, more ipsi-preferred neurons (19/22, 86%) were observed after right UL (p = 6.056 × 10−5), while left UL caused more contra-preferred neurons (13/20, 65%) (p = 0.058). In particular, the convergent neurons mainly led this biased difference (ipsi-, 100% after right UL and contra-, 89% after left UL) (p < 0.002). Conclusions: The directional preference of the neurons depended on the side of the lesion, and its dominance was mainly led by the convergent neurons.
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33
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Facchini J, Rastoldo G, Xerri C, Péricat D, El Ahmadi A, Tighilet B, Zennou-Azogui Y. Unilateral vestibular neurectomy induces a remodeling of somatosensory cortical maps. Prog Neurobiol 2021; 205:102119. [PMID: 34246703 DOI: 10.1016/j.pneurobio.2021.102119] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 06/23/2021] [Accepted: 07/06/2021] [Indexed: 10/20/2022]
Abstract
Unilateral Vestibular Neurectomy (UVN) induces a postural syndrome whose compensation over time is underpinned by multimodal sensory substitution processes. However, at a chronic stage of compensation, UVN rats exhibit an enduring postural asymmetry expressed by an increase in the body weight on the ipsilesional paws. Given the anatomo-functional links between the vestibular nuclei and the primary somatosensory cortex (S1), we explored the interplay of vestibular and somatosensory cortical inputs following acute and chronic UVN. We determined whether the enduring imbalance in tactilo-plantar inputs impacts response properties of S1 cortical neurons and organizational features of somatotopic maps. We performed electrophysiological mapping of the hindpaw cutaneous representations in S1, immediately and one month after UVN. In parallel, we assessed the posturo-locomotor imbalance during the compensation process. UVN immediately induces an expansion of the cortical neuron cutaneous receptive fields (RFs) leading to a partial dedifferentiation of somatotopic maps. This effect was demonstrated for the ventral skin surface representations and was greater on the contralesional hindpaw for which the neuronal threshold to skin pressure strongly decreased. The RF enlargement was amplified for the representation of the ipsilesional hindpaw in relation to persistent postural asymmetries, but was transitory for the contralesional one. Our study shows, for the first time, that vestibular inputs exert a modulatory influence on S1 neuron's cutaneous responses. The lesion-induced cortical malleability highlights the influence of vestibular inputs on tactile processing related to postural control.
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Affiliation(s)
- Justine Facchini
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France
| | - Guillaume Rastoldo
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France
| | - Christian Xerri
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France
| | - David Péricat
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France
| | - Abdessadek El Ahmadi
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France
| | - Brahim Tighilet
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France.
| | - Yoh'i Zennou-Azogui
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Cognitives (LNC), UMR 7291, Marseille, France.
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34
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Montardy Q, Wei M, Liu X, Yi T, Zhou Z, Lai J, Zhao B, Besnard S, Tighilet B, Chabbert C, Wang L. Selective optogenetic stimulation of glutamatergic, but not GABAergic, vestibular nuclei neurons induces immediate and reversible postural imbalance in mice. Prog Neurobiol 2021; 204:102085. [PMID: 34171443 DOI: 10.1016/j.pneurobio.2021.102085] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 04/21/2021] [Accepted: 05/25/2021] [Indexed: 11/24/2022]
Abstract
Glutamatergic and GABAergic neurons represent the neural components of the medial vestibular nuclei. We assessed the functional role of glutamatergic and GABAergic neuronal pathways arising from the vestibular nuclei (VN) in the maintenance of gait and balance by optogenetically stimulating the VN in VGluT2-cre and GAD2-cre mice. We demonstrate that glutamatergic, but not GABAergic VN neuronal subpopulation is responsible for immediate and strong posturo-locomotor deficits, comparable to unilateral vestibular deafferentation models. During optogenetic stimulation, the support surface dramatically increased in VNVGluT2+ mice, and rapidly fell back to baseline after stimulation, whilst it remained unchanged during similar stimulation of VNGAD2+ mice. This effect persisted when vestibular tactilo kinesthesic plantar inputs were removed. Posturo-locomotor alterations evoked in VNVGluT2+ animals were still present immediately after stimulation, while they disappeared 1 h later. Overall, these results indicate a fundamental role for VNVGluT2+ neurons in balance and posturo-locomotor functions, but not for VNGAD2+ neurons, in this specific context. This new optogenetic approach will be useful to characterize the role of the different VN neuronal populations involved in vestibular physiology and pathophysiology.
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Affiliation(s)
- Q Montardy
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China; GDR Physiopathologie Vestibulaire - unité GDR2074 CNRS, France
| | - M Wei
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - X Liu
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China
| | - T Yi
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China
| | - Z Zhou
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China; McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - J Lai
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China
| | - B Zhao
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China
| | - S Besnard
- Aix Marseille University-CNRS, Laboratory of Sensory and Cognitive Neurosciences, UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France; Université de Caen Normandie, CHU de Caen, Caen, France; GDR Physiopathologie Vestibulaire - unité GDR2074 CNRS, France
| | - B Tighilet
- Aix Marseille University-CNRS, Laboratory of Sensory and Cognitive Neurosciences, UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France; GDR Physiopathologie Vestibulaire - unité GDR2074 CNRS, France.
| | - C Chabbert
- Aix Marseille University-CNRS, Laboratory of Sensory and Cognitive Neurosciences, UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France; GDR Physiopathologie Vestibulaire - unité GDR2074 CNRS, France.
| | - L Wang
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China.
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35
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Manzari L, Koch G, Tramontano M. Selective Asymmetry of Ocular Vestibular-Evoked Myogenic Potential in Patients with Acute Utricular Macula Loss. J Int Adv Otol 2021; 17:58-63. [PMID: 33605223 PMCID: PMC7901419 DOI: 10.5152/iao.2020.18012020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 11/02/2020] [Accepted: 11/05/2020] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES We retrospectively evaluated a chart review of 3,525 patients evaluated for any acute disturbance. A total of 1,504 patients with acute vestibular syndrome (AVS) received an instrumental vestibular assessment within 72 h from the onset of the symptoms evaluated using simultaneously a combination of ocular vestibular-evoked myogenic potential (oVEMPs), cervical vestibular-evoked myogenic potential (cVEMPs), video head-impulse test (vHIT), and subjective visual vertical (SVV) were included in this study. MATERIALS AND METHODS A total of 41 patients with AVS that showed a normal horizontal canal function tested with vHIT, a normal cVEMP function, unilaterally reduced or absent oVEMP n10, and an altered SVV were enrolled. RESULTS We found that although these patients referred acute vertigo and presented spontaneous nystagmus, they showed physiological values of vHIT and a normal saccular function, as shown by symmetrical cVEMPs. CONCLUSION Our findings support the hypothesis that a percentage of patients evaluated during an AVS using an instrumental vestibular assessment could present selective utricular macula dysfunction.
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Affiliation(s)
| | - Giacomo Koch
- Fondazione Santa Lucia IRCCS, Rome, Italy;Department of Neuroscience and Rehabilitation, University of Ferrara, Ferrara, Italy
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36
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Tozzi A, Bellingacci L, Pettorossi VE. Rapid Estrogenic and Androgenic Neurosteroids Effects in the Induction of Long-Term Synaptic Changes: Implication for Early Memory Formation. Front Neurosci 2020; 14:572511. [PMID: 33192257 PMCID: PMC7653679 DOI: 10.3389/fnins.2020.572511] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 08/21/2020] [Indexed: 11/17/2022] Open
Abstract
Mounting experimental evidence demonstrate that sex neuroactive steroids (neurosteroids) are essential for memory formation. Neurosteroids have a profound impact on the function and structure of neural circuits and their local synthesis is necessary for the induction of both long-term potentiation (LTP) and long-term depression (LTD) of synaptic transmission and for neural spine formation in different areas of the central nervous system (CNS). Several studies demonstrated that in the hippocampus, 17β-estradiol (E2) is necessary for inducing LTP, while 5α-dihydrotestosterone (DHT) is necessary for inducing LTD. This contribution has been proven by administering sex neurosteroids in rodent models and by using blocking agents of their synthesis or of their specific receptors. The general opposite role of sex neurosteroids in synaptic plasticity appears to be dependent on their different local availability in response to low or high frequency of synaptic stimulation, allowing the induction of bidirectional synaptic plasticity. The relevant contribution of these neurosteroids to synaptic plasticity has also been described in other brain regions involved in memory processes such as motor learning, as in the case of the vestibular nuclei, the cerebellum, and the basal ganglia, or as the emotional circuit of the amygdala. The rapid effects of sex neurosteroids on neural synaptic plasticity need the maintenance of a tonic or phasic local steroid synthesis determined by neural activity but might also be influenced by circulating hormones, age, and gender. To disclose the exact mechanisms how sex neurosteroids participate in finely tuning long-term synaptic changes and spine remodeling, further investigation is required.
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Affiliation(s)
- Alessandro Tozzi
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Laura Bellingacci
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
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37
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Curthoys IS. The Anatomical and Physiological Basis of Clinical Tests of Otolith Function. A Tribute to Yoshio Uchino. Front Neurol 2020; 11:566895. [PMID: 33193004 PMCID: PMC7606994 DOI: 10.3389/fneur.2020.566895] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 09/18/2020] [Indexed: 12/15/2022] Open
Abstract
Otolithic receptors are stimulated by gravitoinertial force (GIF) acting on the otoconia resulting in deflections of the hair bundles of otolithic receptor hair cells. The GIF is the sum of gravitational force and the inertial force due to linear acceleration. The usual clinical and experimental tests of otolith function have used GIFs (roll tilts re gravity or linear accelerations) as test stimuli. However, the opposite polarization of receptors across each otolithic macula is puzzling since a GIF directed across the otolith macula will excite receptors on one side of the line of polarity reversal (LPR at the striola) and simultaneously act to silence receptors on the opposite side of the LPR. It would seem the two neural signals from the one otolith macula should cancel. In fact, Uchino showed that instead of canceling, the simultaneous stimulation of the oppositely polarized hair cells enhances the otolithic response to GIF—both in the saccular macula and the utricular macula. For the utricular system there is also commissural inhibitory interaction between the utricular maculae in each ear. The results are that the one GIF stimulus will cause direct excitation of utricular receptors in the activated sector in one ear as well as indirect excitation resulting from the disfacilitation of utricular receptors in the corresponding sector on the opposite labyrinth. There are effectively two complementary parallel otolithic afferent systems—the sustained system concerned with signaling low frequency GIF stimuli such as roll head tilts and the transient system which is activated by sound and vibration. Clinical tests of the sustained otolith system—such as ocular counterrolling to roll-tilt or tests using linear translation—do not show unilateral otolithic loss reliably, whereas tests of transient otolith function [vestibular evoked myogenic potentials (VEMPs) to brief sound and vibration stimuli] do show unilateral otolithic loss. The opposing sectors of the maculae also explain the results of galvanic vestibular stimulation (GVS) where bilateral mastoid galvanic stimulation causes ocular torsion position similar to the otolithic response to GIF. However, GVS stimulates canal afferents as well as otolithic afferents so the eye movement response is complex.
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Affiliation(s)
- Ian S Curthoys
- Vestibular Research Laboratory, School of Psychology, The University of Sydney, Sydney, NSW, Australia
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38
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Smith PF. Why the cerebellar shutdown/clampdown hypothesis of vestibular compensation is inconsistent with neurophysiological evidence. J Vestib Res 2020; 30:295-303. [PMID: 33044204 DOI: 10.3233/ves-200715] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Vestibular compensation is the process by which the central nervous system (CNS) attempts to adapt to the loss of vestibular sensory inputs. As such, the compensation process is critically involved in the vestibular rehabilitation programs that are implemented by physical therapists for patients with vestibular disorders. One hypothesis regarding vestibular compensation, which has persisted in some of the published vestibular compensation literature and particularly on some vestibular and physical therapy websites, is the 'cerebellar shutdown' or 'cerebellar clampdown' hypothesis proposed by McCabe and Ryu in 1969. This hypothesis proposes that the cerebellum inhibits neuronal activity in the bilateral vestibular nuclei (VN) following unilateral vestibular loss (UVL), causing the VN contralateral to the UVL to be electrically silent during the early phases of vestibular compensation. Despite a wealth of evidence against this idea, it has gained traction amongst some physical therapists and has implications for vestibular rehabilitation early in the compensation process. CONCLUSIONS In this paper it is argued that the 'cerebellar shutdown' or 'clampdown' hypothesis is inconsistent with well accepted neurophysiological and imaging evidence and that it is also logically flawed.
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Affiliation(s)
- Paul F Smith
- Department of Pharmacology and Toxicology, and Brain Health Research Centre, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.,The Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, New Zealand
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39
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Soupiadou P, Gordy C, Forsthofer M, Sanchez-Gonzalez R, Straka H. Acute consequences of a unilateral VIIIth nerve transection on vestibulo-ocular and optokinetic reflexes in Xenopus laevis tadpoles. J Neurol 2020; 267:62-75. [PMID: 32915311 PMCID: PMC7718200 DOI: 10.1007/s00415-020-10205-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 08/28/2020] [Accepted: 08/29/2020] [Indexed: 12/12/2022]
Abstract
Loss of peripheral vestibular function provokes severe impairments of gaze and posture stabilization in humans and animals. However, relatively little is known about the extent of the instantaneous deficits. This is mostly due to the fact that in humans a spontaneous loss often goes unnoticed initially and targeted lesions in animals are performed under deep anesthesia, which prevents immediate evaluation of behavioral deficits. Here, we use isolated preparations of Xenopus laevis tadpoles with functionally intact vestibulo-ocular (VOR) and optokinetic reflexes (OKR) to evaluate the acute consequences of unilateral VIIIth nerve sections. Such in vitro preparations allow lesions to be performed in the absence of anesthetics with the advantage to instantly evaluate behavioral deficits. Eye movements, evoked by horizontal sinusoidal head/table rotation in darkness and in light, became reduced by 30% immediately after the lesion and were diminished by 50% at 1.5 h postlesion. In contrast, the sinusoidal horizontal OKR, evoked by large-field visual scene motion, remained unaltered instantaneously but was reduced by more than 50% from 1.5 h postlesion onwards. The further impairment of the VOR beyond the instantaneous effect, along with the delayed decrease of OKR performance, suggests that the immediate impact of the sensory loss is superseded by secondary consequences. These potentially involve homeostatic neuronal plasticity among shared VOR-OKR neuronal elements that are triggered by the ongoing asymmetric activity. Provided that this assumption is correct, a rehabilitative reduction of the vestibular asymmetry might restrict the extent of the secondary detrimental effect evoked by the principal peripheral impairment.
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Affiliation(s)
- Parthena Soupiadou
- Department Biology II, Ludwig-Maximilians-University Munich, Großhaderner Str. 2, 82152, Planegg, Germany.,Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, Großhaderner Str. 2, 82152, Planegg, Germany
| | - Clayton Gordy
- Department Biology II, Ludwig-Maximilians-University Munich, Großhaderner Str. 2, 82152, Planegg, Germany.,Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, Großhaderner Str. 2, 82152, Planegg, Germany
| | - Michael Forsthofer
- Department Biology II, Ludwig-Maximilians-University Munich, Großhaderner Str. 2, 82152, Planegg, Germany.,Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, Großhaderner Str. 2, 82152, Planegg, Germany
| | - Rosario Sanchez-Gonzalez
- Department Biology II, Ludwig-Maximilians-University Munich, Großhaderner Str. 2, 82152, Planegg, Germany
| | - Hans Straka
- Department Biology II, Ludwig-Maximilians-University Munich, Großhaderner Str. 2, 82152, Planegg, Germany.
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40
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El-Saied S, Zaknoun M, Alatawna O, Joshua BZ, Kabahaa N, Kaplan DM, Lewis EC. Trauma-induced vestibular dysfunction: Possible functional repair under α1-antitrypsin-rich conditions. Cell Immunol 2020; 356:104150. [PMID: 32823037 DOI: 10.1016/j.cellimm.2020.104150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 05/26/2020] [Accepted: 05/29/2020] [Indexed: 11/18/2022]
Abstract
Transient vestibular organ deafferentation, such that is caused by traumatic tissue injury, is presently addressed by corticosteroid therapy. However, restoration of neurophysiological properties is rarely achieved. Here, it was hypothesized that the tissue-protective attributes of α1-antityrpsin (AAT) may promote restoration of neuronal function. Inner ear injury was inflicted by unilateral labyrinthotomy in wild-type mice and in mice overexpressing human AAT. A 2-week-long assessment of vestibular signs followed. All animals responded with peak vestibular dysfunction scores within 4 h after local trauma. While wild-type animals displayed partial or no recovery across 7 days post-injury, AAT-rich group exhibited early recovery: from behavioral score 9-out-of-9 at peak to 4.8 ± 0.44 (mean ± SD) within 8 h from injury, a time when wild-type mice scored 8.6 ± 0.54 (p < 0.0001), and from vestibular score 15-out-of-15 to 7.8 ± 2.2 within 24 h, when wild-type mice scored 13.0 ± 2.0 (p < 0.01). Thus, recovery and functional normalisation of an injured vestibular compartment is achievable without corticosteroid therapy; expedited tissue repair processes appear to result from elevated circulating AAT levels. This study lays the foundation for exploring the molecular and cellular mediators of AAT within the repair processes of the delicate microscopic structures of the vestibular end organ.
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Affiliation(s)
- Sabri El-Saied
- Department of Otolaryngology-Head & Neck Surgery, Soroka University Medical Center, Beer-Sheva, Israel; Department of Clinical Biochemistry & Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
| | - Melodie Zaknoun
- Department of Clinical Biochemistry & Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Osama Alatawna
- Department of Clinical Biochemistry & Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Ben-Zion Joshua
- Department of Otolaryngology-Head & Neck Surgery, Soroka University Medical Center, Beer-Sheva, Israel
| | - Noor Kabahaa
- Department of Clinical Biochemistry & Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Daniel M Kaplan
- Department of Otolaryngology-Head & Neck Surgery, Soroka University Medical Center, Beer-Sheva, Israel
| | - Eli C Lewis
- Department of Clinical Biochemistry & Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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Tighilet B, Rastoldo G, Chabbert C. [The adult brain produces new neurons to restore balance after vestibular loss]. Med Sci (Paris) 2020; 36:581-591. [PMID: 32614308 DOI: 10.1051/medsci/2020112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Following partial or total loss of peripheral vestibular inputs, a phenomenon called central vestibular compensation takes place in the hours and days following the injury. This neuroplasticity process involves a mosaic of profound rearrangements within the brain stem vestibular nuclei. Among them, the setting of a new neuronal network is maybe the most original and unexpected, as it involves an adult reactive neurogenesis in a brain area not reported as neurogenic so far. Both the survival and functionality of this newly generated neuronal network will depend on its integration to pre-existing networks in the deafferented structure. Far from being aberrant, this new structural organization allows the use of inputs from other sensory modalities (vision and proprioception) to promote the restoration of the posture and equilibrium. We choose here to detail this model, which does not belong to the traditional niches of adult neurogenesis, but it is the best example so far of the reparative role of the adult neurogenesis. Not only it represents an original neuroplasticity mechanism, interesting for basic neuroscience, but it also opens new medical perspectives for the development of therapeutic approaches to alleviate vestibular disorders.
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Affiliation(s)
- Brahim Tighilet
- Aix Marseille Université-CNRS, Laboratoire de neurosciences sensorielles et cognitives, LNSC UMR 7260. Équipe Physiopathologie et Thérapie des Désordres Vestibulaires, Groupe de Recherche Vertige (GDR#2074), 3 place Victor Hugo, 13331 Marseille Cedex 3, France
| | - Guillaume Rastoldo
- Aix Marseille Université-CNRS, Laboratoire de neurosciences sensorielles et cognitives, LNSC UMR 7260. Équipe Physiopathologie et Thérapie des Désordres Vestibulaires, Groupe de Recherche Vertige (GDR#2074), 3 place Victor Hugo, 13331 Marseille Cedex 3, France
| | - Christian Chabbert
- Aix Marseille Université-CNRS, Laboratoire de neurosciences sensorielles et cognitives, LNSC UMR 7260. Équipe Physiopathologie et Thérapie des Désordres Vestibulaires, Groupe de Recherche Vertige (GDR#2074), 3 place Victor Hugo, 13331 Marseille Cedex 3, France
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Surgical techniques and functional evaluation for vestibular lesions in the mouse: unilateral labyrinthectomy (UL) and unilateral vestibular neurectomy (UVN). J Neurol 2020; 267:51-61. [PMID: 32556569 PMCID: PMC7718198 DOI: 10.1007/s00415-020-09960-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/26/2020] [Accepted: 05/28/2020] [Indexed: 12/22/2022]
Abstract
OBJECTIVE Unilateral labyrinthectomy (UL) and unilateral vestibular neurectomy (UVN) are two surgical methods to produce vestibular lesions in the mouse. The objective of this study was to describe the surgical technique of both methods, and compare functional compensation using vestibulo-ocular reflex-based tests. METHODS UL and UVN were each performed on groups of seven and ten mice, respectively. Main surgical landmarks were the facial nerve, the external auditory canal and the sternomastoid and digastric muscles. For UL, the sternomastoid muscle was elevated to expose the mastoid, which was drilled to destroy the labyrinth. For UVN, the bulla was drilled opened and a transcochlear approach enabled the identification of the vestibulo-cochlear nerve exiting the brainstem, which was sectioned and the ganglion of Scarpa suctioned. Behaviour and vestibular function were analysed before surgery and at 1, 4, 7 days and at 1 month postlesion using sinusoidal rotation, off-vertical axis rotation, static head tilts and angular velocity steps. RESULTS UL is a faster and safer procedure than UVN (operative time 16.3 vs 20.5 min, p = 0.19; survival rate 86% vs 60%, p = 0.25). UVN was more severe with significantly worse behavioural scores at day 4 and day 7 (p < 0.001). Vestibular compensation was overall similar during the first week and at 1 month (non-statistically significant difference). CONCLUSION Both UL and UVN procedures can routinely be performed in the mouse with similar post-operative recovery and behavioural compensation. The operative risk of vascular or neurological damage is smaller in UL compared to UVN. UVN may be required for specific research protocols studying central cellular process specifically related to the destruction of the ganglion of Scarpa and following vestibular nerve degeneration.
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A 10-week yoga practice has no effect on cognition, but improves balance and motor learning by attenuating brain-derived neurotrophic factor levels in older adults. Exp Gerontol 2020; 138:110998. [PMID: 32544572 DOI: 10.1016/j.exger.2020.110998] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 05/28/2020] [Accepted: 06/01/2020] [Indexed: 12/23/2022]
Abstract
Despite studies investigating the effect of yoga on cognitive and motor functioning in older adults, the effect on dual-task performance and motor learning and the specific mechanisms underlying the positive effect of yoga remain unclear. Thus, the aim of this study was to investigate the effects of yoga on cognition, balance under single- and dual-task conditions, and motor learning. The potential role of brain-derived neurotrophic factor (BDNF) in induced improvement was also explored. Participants aged 60-79 years were randomized to either a control group (n = 15) or a yoga group (n = 18) for a 10-week period. The yoga group received 90-min duration yoga classes two times per week. Changes in cognition, balance under single- and dual-task conditions, and learning fast and accurate reaching movements were assessed. Yoga practice decreased (P < 0.05) the velocity vector of the center of pressure under single- and dual-task conditions, whereas no changes in cognitive performance were observed. Although reaction and movement times during learning were decreased in both groups (P < 0.05), a faster reaction time (P < 0.05) and shorter movement time (P < 0.05) were observed in the yoga group than in the control group. Significant moderate relationships (P < 0.05) between changes in BDNF levels and functional improvements were observed. Thus, 10 weeks of yoga practice resulted in improved balance and learning in the speed-accuracy motor task that were mediated by increased BDNF levels, but had no impact on cognition in older adults.
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Rastoldo G, Marouane E, El Mahmoudi N, Péricat D, Bourdet A, Timon-David E, Dumas O, Chabbert C, Tighilet B. Quantitative Evaluation of a New Posturo-Locomotor Phenotype in a Rodent Model of Acute Unilateral Vestibulopathy. Front Neurol 2020; 11:505. [PMID: 32582016 PMCID: PMC7291375 DOI: 10.3389/fneur.2020.00505] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 05/07/2020] [Indexed: 12/19/2022] Open
Abstract
Vestibular pathologies are difficult to diagnose. Existing devices make it possible to quantify and follow the evolution of posturo-locomotor symptoms following vestibular loss in static conditions. However, today, there are no diagnostic tools allowing the quantitative and spontaneous analysis of these symptoms in dynamic situations. With this in mind, we used an open-field video tracking test aiming at identifying specific posturo-locomotor markers in a rodent model of vestibular pathology. Using Ethovision XT 14 software (Noldus), we identified and quantified several behavioral parameters typical of unilateral vestibular lesions in a rat model of vestibular pathology. The unilateral vestibular neurectomy (UVN) rat model reproduces the symptoms of acute unilateral peripheral vestibulopathy in humans. Our data show deficits in locomotion velocity, distance traveled and animal mobility in the first day after the injury. We also highlighted alterations in several parameters, such as head and body acceleration, locomotor pattern, and position of the body, as well as “circling” behavior after vestibular loss. Here, we provide an enriched posturo-locomotor phenotype specific to full and irreversible unilateral vestibular loss. This test helps to strengthen the quantitative evaluation of vestibular disorders in unilateral vestibular lesion rat model. It may also be useful for testing pharmacological compounds promoting the restoration of balance. Transfer of these novel evaluation parameters to human pathology may improve the diagnosis of acute unilateral vestibulopathies and could better follow the evolution of the symptoms upon pharmacological and physical rehabilitation.
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Affiliation(s)
- Guillaume Rastoldo
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Groupe de Recherche Vertige (GDR#2074), Marseille, France
| | - Emna Marouane
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Groupe de Recherche Vertige (GDR#2074), Marseille, France
| | - Nada El Mahmoudi
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Groupe de Recherche Vertige (GDR#2074), Marseille, France
| | - David Péricat
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Groupe de Recherche Vertige (GDR#2074), Marseille, France
| | - Audrey Bourdet
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Groupe de Recherche Vertige (GDR#2074), Marseille, France
| | - Elise Timon-David
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Groupe de Recherche Vertige (GDR#2074), Marseille, France
| | - Olivier Dumas
- Société Française de Kinésithérapie Vestibulaire, Lyon, France
| | - Christian Chabbert
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Groupe de Recherche Vertige (GDR#2074), Marseille, France
| | - Brahim Tighilet
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Groupe de Recherche Vertige (GDR#2074), Marseille, France
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Marouane E, Rastoldo G, El Mahmoudi N, Péricat D, Chabbert C, Artzner V, Tighilet B. Identification of New Biomarkers of Posturo-Locomotor Instability in a Rodent Model of Vestibular Pathology. Front Neurol 2020; 11:470. [PMID: 32547480 PMCID: PMC7273747 DOI: 10.3389/fneur.2020.00470] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 04/29/2020] [Indexed: 01/08/2023] Open
Abstract
The vestibular system plays a crucial role in maintaining postural balance. Unilateral vestibular lesions result in a typical syndrome characterized by postural imbalance, altered locomotor patterns and gaze stabilization, as well as cognitive and neurovegetative disorders. One of the main difficulties encountered in the development of new anti-vertigo drugs is the lack of sensitivity in the evaluation of this syndrome. Qualitative assessments of the vestibular syndrome have been developed, but methods of conducting quantitative evaluations are critically lacking. Recently, assessments with a dynamic weight-bearing device (DWB®, Bioseb) revealed postural alterations in rats subjected to unilateral vestibular neurectomy (UVN). Our team is evaluating a new version of this device capable of quantifying additional parameters of postural and locomotor equilibrium. The objective of this study was to use this device to assess these new posturo-locomotor parameters in a rat model of a vestibular pathology. The biomarkers measured by this device are as follows: the barycenter, the support surface and the weight distribution of the rats when they were moving or stationary. Before UVN, the rats showed a symmetric distribution of their weight along the lateral axis. In the acute phase after UVN on the left side, the rats distributed more weight on the right side than on the left side and then distributed more weight on the left side. These results corroborate those presented in our previous study. The support surface of the rats increased between 1 day and 30 days after UVN, and the barycenter distribution reflected the weight distribution. In addition, our results show smaller changes in the weight distributions when the animals are moving compared with when they are stationary in the acute phase after UVN. This study provides new information on the static and dynamic postural balance patterns observed after unilateral vestibular loss in rats. These data are relevant because they objectively quantify the posturo-locomotor component of vestibular syndrome as well as the compensatory strategies used after vestibular loss. These results may guide the development of rehabilitation protocols for vestibular patients and the validation of pharmacological compounds favoring the restoration of equilibrium.
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Affiliation(s)
- Emna Marouane
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France.,BIOSEB SAS, Vitrolles, France
| | - Guillaume Rastoldo
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France
| | - Nada El Mahmoudi
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France
| | - David Péricat
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France
| | - Christian Chabbert
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France
| | | | - Brahim Tighilet
- Aix Marseille Université-CNRS, Laboratoire de Neurosciences Sensorielles et Cognitives, LNSC UMR 7260, Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France
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Clément GR, Boyle RD, George KA, Nelson GA, Reschke MF, Williams TJ, Paloski WH. Challenges to the central nervous system during human spaceflight missions to Mars. J Neurophysiol 2020; 123:2037-2063. [DOI: 10.1152/jn.00476.2019] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Space travel presents a number of environmental challenges to the central nervous system, including changes in gravitational acceleration that alter the terrestrial synergies between perception and action, galactic cosmic radiation that can damage sensitive neurons and structures, and multiple factors (isolation, confinement, altered atmosphere, and mission parameters, including distance from Earth) that can affect cognition and behavior. Travelers to Mars will be exposed to these environmental challenges for up to 3 years, and space-faring nations continue to direct vigorous research investments to help elucidate and mitigate the consequences of these long-duration exposures. This article reviews the findings of more than 50 years of space-related neuroscience research on humans and animals exposed to spaceflight or analogs of spaceflight environments, and projects the implications and the forward work necessary to ensure successful Mars missions. It also reviews fundamental neurophysiology responses that will help us understand and maintain human health and performance on Earth.
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Affiliation(s)
| | - Richard D. Boyle
- National Aeronautics and Space Administration, Ames Research Center, Moffett Field, California
| | | | - Gregory A. Nelson
- Division of Biomedical Engineering Sciences, School of Medicine Loma Linda University, Loma Linda, California
| | - Millard F. Reschke
- National Aeronautics and Space Administration, Johnson Space Center, Houston, Texas
| | - Thomas J. Williams
- National Aeronautics and Space Administration, Johnson Space Center, Houston, Texas
| | - William H. Paloski
- National Aeronautics and Space Administration, Johnson Space Center, Houston, Texas
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Guajardo‐Vergara C, Perez‐Fernandez N. A New and Faster Method to Assess Vestibular Compensation: A Cross‐Sectional Study. Laryngoscope 2020; 130:E911-E917. [DOI: 10.1002/lary.28505] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 12/27/2019] [Accepted: 12/30/2019] [Indexed: 01/03/2023]
Affiliation(s)
- Carlos Guajardo‐Vergara
- Department of Otorhinolaryngology Clínica Universidad de Navarra Pamplona Spain
- Escuela de Fonoaudiología, Universidad Austral de Chile Sede Puerto Montt Chile
| | - Nicolas Perez‐Fernandez
- Department of Otorhinolaryngology Clínica Universidad de Navarra Madrid Spain
- Research Group Interdisciplinar Theragnosis and Radiosomics, University of Navarra Madrid Spain
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Oliveira LNDR, Oliveira CLDA, Lopes KDC, Ganança FF. Diagnostic assessment of patients with Meniere's disease through caloric testing and the video-head-impulse test. Braz J Otorhinolaryngol 2019; 87:428-433. [PMID: 31870737 PMCID: PMC9422366 DOI: 10.1016/j.bjorl.2019.10.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 09/11/2019] [Accepted: 10/08/2019] [Indexed: 11/17/2022] Open
Abstract
Introduction Meniere's disease is a labyrinth disease that usually presents with episodes of spontaneous vertigo associated with sensorineural hearing loss, tinnitus and ipsi- and unilateral aural fullness in most cases. Vestibular function tests, video-head-impulse test and the caloric test, are not specific for diagnosis of the disease, but may show alterations that help to evaluate the functional impairment. Objective To describe the results obtained at the caloric test and video-head-impulse test in patients with definite Meniere's disease and compare them between symptomatic, asymptomatic ears and those of the control group. Methods Cross-sectional and observational study including patients with definite Meniere's disease diagnosed according to the Bárány Society criteria (2015) and healthy individuals (control group) undergoing caloric test and video-head-impulse test. All subjects were assessed by neurotological anamnesis and audiological evaluation (pure-tone, vocal and immittance audiometry) to characterize the sample. The findings obtained at the caloric test and video-head-impulse test were described and compared between the symptomatic and asymptomatic ears of patients with Meniere's disease and those of the control group. Results Thirty-two patients with definite Meniere's disease were evaluated, with a mean age of 45.7 years, mostly females (68.8%) and unilateral disease. The control group consisted of 20 healthy individuals, with a mean age of 44.7 years, mostly females (70.0%). The groups were homogeneous in relation to age and gender. The patients’ main complaint was vertigo (71.9%), and most patients had more than six episodes in the last six months (71.9%). Moderate sensorineural hearing loss was present in 38.5% of patients. The prevalence of hyporeflexia at the caloric test was higher in symptomatic (56.4%) and asymptomatic (36%) ears of patients with Meniere's disease compared to the ears of control subjects (7.5%), p < 0.001 and p = 0.004, respectively. Video-head-impulse test alterations in the lateral semicircular canals were more frequent in the symptomatic ears of patients with Meniere's disease than in the ears of control subjects (p = 0.026). Conclusion Most patients with definite Meniere's disease showed hyporeflexia at the caloric test and video-head-impulse test with normal function in the symptomatic ear. Vestibular hyporeflexia at the caloric test was more frequent in the symptomatic and asymptomatic ears of patients with Meniere's disease than in the control group. The video-head-impulse test showed more alterations in the lateral semicircular canals.
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Affiliation(s)
- Lívia Noleto de Rezende Oliveira
- Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina, Disciplina de Otologia e Otoneurologia, São Paulo, SP, Brazil.
| | | | - Karen de Carvalho Lopes
- Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina, Disciplina de Otologia e Otoneurologia, São Paulo, SP, Brazil
| | - Fernando Freitas Ganança
- Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina, Disciplina de Otologia e Otoneurologia, São Paulo, SP, Brazil
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Curthoys IS. Concepts and Physiological Aspects of the Otolith Organ in Relation to Electrical Stimulation. Audiol Neurootol 2019; 25:25-34. [PMID: 31553977 DOI: 10.1159/000502712] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 08/13/2019] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND This paper discusses some of the concepts and major physiological issues in developing a means of electrically stimulating the otolithic system, with the final goal being the electrical stimulation of the otoliths in human patients. It contrasts the challenges of electrical stimulation of the otolith organs as compared to stimulation of the semicircular canals. Electrical stimulation may consist of trains of short-duration pulses (e.g., 0.1 ms duration at 400 Hz) by selective electrodes on otolith maculae or otolithic afferents, or unselective maintained DC stimulation by large surface electrodes on the mastoids - surface galvanic stimulation. SUMMARY Recent anatomical and physiological results are summarized in order to introduce some of the unique issues in electrical stimulation of the otoliths. The first challenge is that each otolithic macula contains receptors with opposite polarization (opposing preferred directions of stimulation), unlike the uniform polarization of receptors in each semicircular canal crista. The puzzle is that in response to the one linear acceleration in the one macula, some otolithic afferents have an increased activation whereas others have decreased activation. Key Messages: At the vestibular nucleus this opposite receptor hair cell polarization and consequent opposite afferent input allow enhanced response to the one linear acceleration, via a "push-pull" neural mechanism in a manner analogous to the enhancement of semicircular canal responses to angular acceleration. Within each otolithic macula there is not just one uniform otolithic neural input to the brain - there are very distinctly different channels of otolithic neural inputs transferring the neural data to the brainstem. As a simplification these channels are characterized as the sustained and transient systems. Afferents in each system have different responses to stimulus onset and maintained stimulation and likely different projections, and most importantly different thresholds for activation by electrical stimulation and different adaptation rates to maintained stimulation. The implications of these differences are considered.
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Affiliation(s)
- Ian S Curthoys
- Vestibular Research Laboratory, School of Psychology, University of Sydney, Sydney, New South Wales, Australia,
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50
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Peripheral vestibular plasticity vs central compensation: evidence and questions. J Neurol 2019; 266:27-32. [DOI: 10.1007/s00415-019-09388-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 05/15/2019] [Accepted: 05/17/2019] [Indexed: 12/18/2022]
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