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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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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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Le Ray D, Guayasamin M. How Does the Central Nervous System for Posture and Locomotion Cope With Damage-Induced Neural Asymmetry? Front Syst Neurosci 2022; 16:828532. [PMID: 35308565 PMCID: PMC8927091 DOI: 10.3389/fnsys.2022.828532] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 02/07/2022] [Indexed: 12/28/2022] Open
Abstract
In most vertebrates, posture and locomotion are achieved by a biomechanical apparatus whose effectors are symmetrically positioned around the main body axis. Logically, motor commands to these effectors are intrinsically adapted to such anatomical symmetry, and the underlying sensory-motor neural networks are correspondingly arranged during central nervous system (CNS) development. However, many developmental and/or life accidents may alter such neural organization and acutely generate asymmetries in motor operation that are often at least partially compensated for over time. First, we briefly present the basic sensory-motor organization of posturo-locomotor networks in vertebrates. Next, we review some aspects of neural plasticity that is implemented in response to unilateral central injury or asymmetrical sensory deprivation in order to substantially restore symmetry in the control of posturo-locomotor functions. Data are finally discussed in the context of CNS structure-function relationship.
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Lacour M, Tardivet L, Thiry A. Posture Deficits and Recovery After Unilateral Vestibular Loss: Early Rehabilitation and Degree of Hypofunction Matter. Front Hum Neurosci 2022; 15:776970. [PMID: 35185493 PMCID: PMC8855301 DOI: 10.3389/fnhum.2021.776970] [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: 09/14/2021] [Accepted: 12/03/2021] [Indexed: 11/27/2022] Open
Abstract
Postural instability and balance impairment are disabling symptoms in patients with acute unilateral peripheral vestibular hypofunction (UVH). Vestibular rehabilitation (VR) is known to improve the vestibular compensation process, but (1) its effect on posture recovery remains poorly understood, (2) little is known about when VR must be done, and (3) whether the degree of vestibular loss matters is uncertain. We analyzed posture control under static (stable support) and dynamic (unstable support) postural tasks performed in different visual conditions [eye open (EO); eyes closed (EC); and optokinetic stimulation] using dynamic posturography. Non-linear analyses of the postural performance (wavelet transform, diffusion analysis, and fractal analysis) were performed in two groups of patients with UVH subjected to the same VR program based on the unidirectional rotation paradigm and performed either early (first 2 weeks) or later (fifth to the sixth week) after vertigo attack. Distribution of the angular horizontal vestibulo-ocular reflex (aVOR) gain values recorded on the hypofunction side before rehabilitation differentiated two distinct sub-groups (cluster analysis) with aVOR gains below or above 0.20. The postural performance of the four sub-groups of patients with UVH (early rehabilitation with aVOR gain <0.20: n = 25 or gain >0.20: n = 19; late rehabilitation with aVOR gain <0.20: n = 15 or gain >0.20: n = 10) tested before VR showed significantly altered postural parameters compared with healthy controls. Greater instability, higher energy to control posture, larger sway without feedback corrections, and lower time of automatic control of posture were observed in static conditions. The four sub-groups recovered near-normal postural performance after VR in the EO and EC conditions, but still exhibited altered postural performance with optokinetic stimulation. In dynamic posturography conditions and before VR, the percentage of patients able to perform the postural tasks with EC and optokinetic stimulation was significantly lower in the two sub-groups with aVOR gain <0.20. After VR, the improvement of the postural parameters depended on the stage of rehabilitation and the degree of vestibular hypofunction. The best balance function recovery was found in the sub-group with early VR and pre-rehabilitation aVOR gain above 0.20, the worst in the sub-group with late rehabilitation and aVOR gain below 0.20. These differences were seen when the vestibular input remains the main sensory cue to control balance, that is, on unstable support without vision or altered visual motion cues. These findings extend to dynamic balance recovery the crucial roles of early rehabilitation and degree of vestibular hypofunction which we have already highlighted for vestibulo-ocular reflex recovery.
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Affiliation(s)
- Michel Lacour
- Neurosciences Department, Aix-Marseille University/CNRS, Marseille, France
- 21 Impasse des Vertus, Fuveau, France
- *Correspondence: Michel Lacour,
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Fayat R, Delgado Betancourt V, Goyallon T, Petremann M, Liaudet P, Descossy V, Reveret L, Dugué GP. Inertial Measurement of Head Tilt in Rodents: Principles and Applications to Vestibular Research. SENSORS (BASEL, SWITZERLAND) 2021; 21:6318. [PMID: 34577524 PMCID: PMC8472891 DOI: 10.3390/s21186318] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/03/2021] [Accepted: 09/13/2021] [Indexed: 12/21/2022]
Abstract
Inertial sensors are increasingly used in rodent research, in particular for estimating head orientation relative to gravity, or head tilt. Despite this growing interest, the accuracy of tilt estimates computed from rodent head inertial data has never been assessed. Using readily available inertial measurement units mounted onto the head of freely moving rats, we benchmarked a set of tilt estimation methods against concurrent 3D optical motion capture. We show that, while low-pass filtered head acceleration signals only provided reliable tilt estimates in static conditions, sensor calibration combined with an appropriate choice of orientation filter and parameters could yield average tilt estimation errors below 1.5∘ during movement. We then illustrate an application of inertial head tilt measurements in a preclinical rat model of unilateral vestibular lesion and propose a set of metrics describing the severity of associated postural and motor symptoms and the time course of recovery. We conclude that headborne inertial sensors are an attractive tool for quantitative rodent behavioral analysis in general and for the study of vestibulo-postural functions in particular.
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Affiliation(s)
- Romain Fayat
- Neurophysiologie des Circuits Cérébraux, Institut de Biologie de l’ENS (IBENS), Ecole Normale Supérieure, UMR CNRS 8197, INSERM U1024, Université PSL, 75005 Paris, France;
- Laboratoire MAP5, UMR CNRS 8145, Université Paris Descartes, 75006 Paris, France
| | | | - Thibault Goyallon
- Laboratoire Jean Kuntzmann, Université Grenoble Alpes, UMR CNRS 5224, INRIA, 38330 Montbonnot-Saint-Martin, France; (T.G.); (L.R.)
| | - Mathieu Petremann
- Preclinical Development, Sensorion SA, 34080 Montpellier, France; (V.D.B.); (M.P.); (P.L.); (V.D.)
| | - Pauline Liaudet
- Preclinical Development, Sensorion SA, 34080 Montpellier, France; (V.D.B.); (M.P.); (P.L.); (V.D.)
| | - Vincent Descossy
- Preclinical Development, Sensorion SA, 34080 Montpellier, France; (V.D.B.); (M.P.); (P.L.); (V.D.)
| | - Lionel Reveret
- Laboratoire Jean Kuntzmann, Université Grenoble Alpes, UMR CNRS 5224, INRIA, 38330 Montbonnot-Saint-Martin, France; (T.G.); (L.R.)
| | - Guillaume P. Dugué
- Neurophysiologie des Circuits Cérébraux, Institut de Biologie de l’ENS (IBENS), Ecole Normale Supérieure, UMR CNRS 8197, INSERM U1024, Université PSL, 75005 Paris, France;
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Lacour M, Thiry A, Tardivet L. Two conditions to fully recover dynamic canal function in unilateral peripheral vestibular hypofunction patients. J Vestib Res 2021; 31:407-421. [PMID: 33749626 DOI: 10.3233/ves-201557] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The crucial role of early vestibular rehabilitation (VR) to recover a dynamic semicircular canal function was recently highlighted in patients with unilateral vestibular hypofunction (UVH). However, wide inter-individual differences were observed, suggesting that parameters other than early rehabilitation are involved. OBJECTIVE The aim of the study was to determine to what extent the degree of vestibular loss assessed by the angular vestibulo-ocular reflex (aVOR) gain could be an additional parameter interfering with rehabilitation in the recovery process. And to examine whether different VR protocols have the same effectiveness with regard to the aVOR recovery. METHODS The aVOR gain and the percentage of compensatory saccades were recorded in 81 UVH patients with the passive head impulse test before and after early VR (first two weeks after vertigo onset: N = 43) or late VR (third to sixth week after onset: N = 38) performed twice a week for four weeks. VR was performed either with the unidirectional rotation paradigm or gaze stability exercises. Supplementary outcomes were the dizziness handicap inventory (DHI) score, and the static and dynamic subjective visual vertical. RESULTS The cluster analysis differentiated two distinct populations of UVH patients with pre-rehab aVOR gain values on the hypofunction side below 0.20 (N = 42) or above 0.20 (N = 39). The mean gain values were respectively 0.07±0.05 and 0.34±0.12 for the lateral canal (p < 0.0001), 0.09±0.06 and 0.44±0.19 for the anterior canal (p < 0.0001). Patients with aVOR gains above 0.20 and early rehab fully recovered dynamic horizontal canal function (0.84±0.14) and showed very few compensatory saccades (18.7% ±20.1%) while those with gains below 0.20 and late rehab did not improve their aVOR gain value (0.16±0.09) and showed compensatory saccades only (82.9% ±23.7%). Similar results were found for the anterior canal function. Recovery of the dynamic function of the lateral canal was found with both VR protocols while it was observed with the gaze stability exercises only for the anterior canal. All the patients reduced their DHI score, normalized their static SVV, and exhibited uncompensated dynamic SVV. CONCLUSIONS Early rehab is a necessary but not sufficient condition to fully recover dynamic canal function. The degree of vestibular loss plays a crucial role too, and to be effective rehabilitation protocols must be carried out in the plane of the semicircular canals.
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Affiliation(s)
- Michel Lacour
- Neurosciences Department, Aix-Marseille University, CNRS, Marseille, France
| | - Alain Thiry
- Physiotherapist, Bd Dubouchage, Nice, France
| | - Laurent Tardivet
- Otorhinolaryngology Department, CHU Nice, Voie Romaine, Nice, France
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Zhang Y, Zhang Y, Tian K, Wang Y, Fan X, Pan Q, Qin G, Zhang D, Chen L, Zhou J. Calcitonin gene-related peptide facilitates sensitization of the vestibular nucleus in a rat model of chronic migraine. J Headache Pain 2020; 21:72. [PMID: 32522232 PMCID: PMC7288551 DOI: 10.1186/s10194-020-01145-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 06/01/2020] [Indexed: 12/23/2022] Open
Abstract
Background Vestibular migraine has recently been recognized as a novel subtype of migraine. However, the mechanism that relate vestibular symptoms to migraine had not been well elucidated. Thus, the present study investigated vestibular dysfunction in a rat model of chronic migraine (CM), and to dissect potential mechanisms between migraine and vertigo. Methods Rats subjected to recurrent intermittent administration of nitroglycerin (NTG) were used as the CM model. Migraine- and vestibular-related behaviors were analyzed. Immunofluorescent analyses and quantitative real-time polymerase chain reaction were employed to detect expressions of c-fos and calcitonin gene-related peptide (CGRP) in the trigeminal nucleus caudalis (TNC) and vestibular nucleus (VN). Morphological changes of vestibular afferent terminals was determined under transmission electron microscopy. FluoroGold (FG) and CTB-555 were selected as retrograde tracers and injected into the VN and TNC, respectively. Lentiviral vectors comprising CGRP short hairpin RNA (LV-CGRP) was injected into the trigeminal ganglion. Results CM led to persistent thermal hyperalgesia, spontaneous facial pain, and prominent vestibular dysfunction, accompanied by the upregulation of c-fos labeling neurons and CGRP immunoreactivity in the TNC (c-fos: vehicle vs. CM = 2.9 ± 0.6 vs. 45.5 ± 3.4; CGRP OD: vehicle vs. CM = 0.1 ± 0.0 vs. 0.2 ± 0.0) and VN (c-fos: vehicle vs. CM = 2.3 ± 0.8 vs. 54.0 ± 2.1; CGRP mRNA: vehicle vs. CM = 1.0 ± 0.1 vs. 2.4 ± 0.1). Furthermore, FG-positive neurons was accumulated in the superficial layer of the TNC, and the number of c-fos+/FG+ neurons were significantly increased in rats with CM compared to the vehicle group (vehicle vs. CM = 25.3 ± 2.2 vs. 83.9 ± 3.0). Meanwhile, CTB-555+ neurons dispersed throughout the VN. The structure of vestibular afferent terminals was less pronounced after CM compared with the peripheral vestibular dysfunction model. In vivo knockdown of CGRP in the trigeminal ganglion significantly reduced the number of c-fos labeling neurons (LV-CGRP vs. LV-NC = 9.9 ± 3.0 vs. 60.0 ± 4.5) and CGRP mRNA (LV-CGRP vs. LV-NC = 1.0 ± 0.1 vs. 2.1 ± 0.2) in the VN, further attenuating vestibular dysfunction after CM. Conclusions These data demonstrates the possibility of sensitization of vestibular nucleus neurons to impair vestibular function after CM, and anti-CGRP treatment to restore vestibular dysfunction in patients with CM.
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Affiliation(s)
- Yun Zhang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 1st Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Yixin Zhang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 1st Youyi Road, Yuzhong District, Chongqing, 400016, China.
| | - Ke Tian
- Department of Vascular Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yunfeng Wang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 1st Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Xiaoping Fan
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 1st Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Qi Pan
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 1st Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Guangcheng Qin
- Laboratory Research Center, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Dunke Zhang
- Laboratory Research Center, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Lixue Chen
- Department of Vascular Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jiying Zhou
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 1st Youyi Road, Yuzhong District, Chongqing, 400016, China
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Cassel R, Bordiga P, Carcaud J, Simon F, Beraneck M, Le Gall A, Benoit A, Bouet V, Philoxene B, Besnard S, Watabe I, Pericat D, Hautefort C, Assie A, Tonetto A, Dyhrfjeld-Johnsen J, Llorens J, Tighilet B, Chabbert C. Morphological and functional correlates of vestibular synaptic deafferentation and repair in a mouse model of acute-onset vertigo. Dis Model Mech 2019; 12:dmm.039115. [PMID: 31213478 PMCID: PMC6679379 DOI: 10.1242/dmm.039115] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 06/06/2019] [Indexed: 12/25/2022] Open
Abstract
Damage to cochlear primary afferent synapses has been shown to be a key factor in various auditory pathologies. Similarly, the selective lesioning of primary vestibular synapses might be an underlying cause of peripheral vestibulopathies that cause vertigo and dizziness, for which the pathophysiology is currently unknown. To thoroughly address this possibility, we selectively damaged the synaptic contacts between hair cells and primary vestibular neurons in mice through the transtympanic administration of a glutamate receptor agonist. Using a combination of histological and functional approaches, we demonstrated four key findings: (1) selective synaptic deafferentation is sufficient to generate acute vestibular syndrome with characteristics similar to those reported in patients; (2) the reduction of the vestibulo-ocular reflex and posturo-locomotor deficits mainly depends on spared synapses; (3) damaged primary vestibular synapses can be repaired over the days and weeks following deafferentation; and (4) the synaptic repair process occurs through the re-expression and re-pairing of synaptic proteins such as CtBP2 and SHANK-1. Primary synapse repair might contribute to re-establishing the initial sensory network. Deciphering the molecular mechanism that supports synaptic repair could offer a therapeutic opportunity to rescue full vestibular input and restore gait and balance in patients. Summary: The molecular rearrangements of the synaptic proteins that accompany the deafferentation and subsequent reafferentation of the inner ear sensors following an excitotoxic insult are demonstrated for the first time.
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Affiliation(s)
- Raphaelle Cassel
- Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Sensorielles et Cognitives - Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, 13000 France
| | - Pierrick Bordiga
- Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Sensorielles et Cognitives - Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, 13000 France
| | - Julie Carcaud
- Integrative Neuroscience and Cognition Center, UMR 8002, CNRS, 75006 Paris, France
| | - François Simon
- Integrative Neuroscience and Cognition Center, UMR 8002, CNRS, 75006 Paris, France.,Sorbonne Paris Cité, Université Paris Descartes, 75006 Paris, France
| | - Mathieu Beraneck
- Integrative Neuroscience and Cognition Center, UMR 8002, CNRS, 75006 Paris, France.,Sorbonne Paris Cité, Université Paris Descartes, 75006 Paris, France
| | | | | | | | | | | | - Isabelle Watabe
- Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Sensorielles et Cognitives - Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, 13000 France
| | - David Pericat
- Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Sensorielles et Cognitives - Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, 13000 France
| | | | - Axel Assie
- Aix-Marseille Université, CNRS, Centrale Marseille, FSCM (FR1739), PRATIM, Marseille, 13000 France
| | - Alain Tonetto
- Aix-Marseille Université, CNRS, Centrale Marseille, FSCM (FR1739), PRATIM, Marseille, 13000 France
| | | | | | - Brahim Tighilet
- Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Sensorielles et Cognitives - Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, 13000 France
| | - Christian Chabbert
- Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Sensorielles et Cognitives - Equipe Physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, 13000 France
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Martins-Lopes V, Bellmunt A, Greguske EA, Maroto AF, Boadas-Vaello P, Llorens J. Quantitative Assessment of Anti-Gravity Reflexes to Evaluate Vestibular Dysfunction in Rats. J Assoc Res Otolaryngol 2019; 20:553-563. [PMID: 31297642 DOI: 10.1007/s10162-019-00730-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 06/20/2019] [Indexed: 12/18/2022] Open
Abstract
The tail-lift reflex and the air-righting reflex are anti-gravity reflexes in rats that depend on vestibular function. To obtain objective and quantitative measures of performance, we recorded these reflexes with slow-motion video in two experiments. In the first experiment, vestibular dysfunction was elicited by acute exposure to 0 (control), 400, 600, or 1000 mg/kg of 3,3'-iminodipropionitrile (IDPN), which causes dose-dependent hair cell degeneration. In the second, rats were exposed to sub-chronic IDPN in the drinking water for 0 (control), 4, or 8 weeks; this causes reversible or irreversible loss of vestibular function depending on exposure time. In the tail-lift test, we obtained the minimum angle defined during the lift and descent maneuver by the nose, the back of the neck, and the base of the tail. In the air-righting test, we obtained the time to right the head. We also obtained vestibular dysfunction ratings (VDRs) using a previously validated behavioral test battery. Each measure, VDR, tail-lift angle, and air-righting time demonstrated dose-dependent loss of vestibular function after acute IDPN and time-dependent loss of vestibular function after sub-chronic IDPN. All measures showed high correlations between each other, and maximal correlation coefficients were found between VDRs and tail-lift angles. In scanning electron microscopy evaluation of the vestibular sensory epithelia, the utricle and the saccule showed diverse pathological outcomes, suggesting that they have a different role in these reflexes. We conclude that these anti-gravity reflexes provide useful objective and quantitative measures of vestibular function in rats that are open to further development.
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Affiliation(s)
- Vanessa Martins-Lopes
- Departament de Ciències Fisiològiques, Institut de Neurociènces, Universitat de Barcelona, Feixa Llarga s/n, 08907, L'Hospitalet de Llobregat, Catalunya, Spain
| | - Anna Bellmunt
- Departament de Ciències Fisiològiques, Institut de Neurociènces, Universitat de Barcelona, Feixa Llarga s/n, 08907, L'Hospitalet de Llobregat, Catalunya, Spain
| | - Erin A Greguske
- Departament de Ciències Fisiològiques, Institut de Neurociènces, Universitat de Barcelona, Feixa Llarga s/n, 08907, L'Hospitalet de Llobregat, Catalunya, Spain.,Institut d'Investigació Biomèdica de Bellvitge, IDIBELL, 08907, L'Hospitalet de Llobregat, Catalunya, Spain
| | - Alberto F Maroto
- Departament de Ciències Fisiològiques, Institut de Neurociènces, Universitat de Barcelona, Feixa Llarga s/n, 08907, L'Hospitalet de Llobregat, Catalunya, Spain.,Institut d'Investigació Biomèdica de Bellvitge, IDIBELL, 08907, L'Hospitalet de Llobregat, Catalunya, Spain
| | - Pere Boadas-Vaello
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Departament de Ciències Mèdiques, Facultat de Medicina, Universitat de Girona, 17003, Girona, Catalunya, Spain
| | - Jordi Llorens
- Departament de Ciències Fisiològiques, Institut de Neurociènces, Universitat de Barcelona, Feixa Llarga s/n, 08907, L'Hospitalet de Llobregat, Catalunya, Spain. .,Institut d'Investigació Biomèdica de Bellvitge, IDIBELL, 08907, L'Hospitalet de Llobregat, Catalunya, Spain.
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10
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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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11
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Qian S, Wang Y, Zhang X. Inhibiting Histamine Signaling Ameliorates Vertigo Induced by Sleep Deprivation. J Mol Neurosci 2019; 67:411-417. [DOI: 10.1007/s12031-018-1244-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 12/11/2018] [Indexed: 10/27/2022]
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12
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Calyx junction dismantlement and synaptic uncoupling precede hair cell extrusion in the vestibular sensory epithelium during sub-chronic 3,3'-iminodipropionitrile ototoxicity in the mouse. Arch Toxicol 2018; 93:417-434. [PMID: 30377733 DOI: 10.1007/s00204-018-2339-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 10/23/2018] [Indexed: 10/28/2022]
Abstract
The cellular and molecular events that precede hair cell (HC) loss in the vestibular epithelium during chronic ototoxic exposure have not been widely studied. To select a study model, we compared the effects of sub-chronic exposure to different concentrations of 3,3'-iminodipropionitrile (IDPN) in the drinking water of two strains of mice and of both sexes. In subsequent experiments, male 129S1/SvImJ mice were exposed to 30 mM IDPN for 5 or 8 weeks; animals were euthanized at the end of the exposure or after a washout period of 13 weeks. In behavioral tests, IDPN mice showed progressive vestibular dysfunction followed by recovery during washout. In severely affected animals, light and electron microscopy observations of the vestibular epithelia revealed HC extrusion towards the endolymphatic cavity. Comparison of functional and ultrastructural data indicated that animals with fully reversible dysfunction did not have significant HC loss or stereociliary damage, but reversible dismantlement of the calyceal junctions that characterize the contact between type I HCs (HCI) and their calyx afferents. Immunofluorescent analysis revealed the loss of calyx junction proteins, Caspr1 and Tenascin-C, during exposure and their recovery during washout. Synaptic uncoupling was also recorded, with loss of pre-synaptic Ribeye and post-synaptic GluA2 puncta, and differential reversibility among the three different kinds of synaptic contacts existing in the epithelium. qRT-PCR analyses demonstrated that some of these changes are at least in part explained by gene expression modifications. We concluded that calyx junction dismantlement and synaptic uncoupling are early events in the mouse vestibular sensory epithelium during sub-chronic IDPN ototoxicity.
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13
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Cassel R, Wiener-Vacher S, El Ahmadi A, Tighilet B, Chabbert C. Reduced Balance Restoration Capacities Following Unilateral Vestibular Insult in Elderly Mice. Front Neurol 2018; 9:462. [PMID: 29988508 PMCID: PMC6026628 DOI: 10.3389/fneur.2018.00462] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/30/2018] [Indexed: 11/16/2022] Open
Abstract
Acute vestibular syndrome (AVS) is characterized by severe posturo-locomotor and vestibulo-oculomotor impairment and accompanies several types of peripheral vestibulopathies (PVP). We know very little about its etiology, how its various symptoms are expressed and how it evolves with age. Robust repair capabilities of primary vestibular synapses have recently been shown to restore behavioral functionality. In this study, we used a mouse model of an excitotoxically induced unilateral vestibular lesion to compare the ability to restore balance and posture between old and young adult mice. We compared the temporal evolution of the evoked vestibular syndrome using a battery of behavioral tests to follow the evolution of postural-locomotor alterations and equilibrium. For the first time, we show that young adult (3 months) and elderly (22 months) mice are together able to restore normal postural-locomotor function following transient unilateral excitotoxic vestibular insult, though with different time courses. This animal study paves way for future, more detailed studies of how the early postural and locomotor disturbances following a unilateral insult are compensated for by various plasticity mechanisms, and in particular how age influences these mechanisms.
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Affiliation(s)
- Raphaelle Cassel
- Laboratoire de Neurosciences Sensorielles et Cognitives - Equipe physiopathologie et Thérapie des Désordres Vestibulaire, Centre National de la Recherche Scientifique, Aix Marseille Université, UMR 7260, Marseille, France
| | - Sylvette Wiener-Vacher
- Laboratoire d'Exploration Fonctionnel de l'Équilibre chez l'Enfant, APHP, Université Paris VII, Paris, France
| | - A El Ahmadi
- Laboratoire de Neurosciences Sensorielles et Cognitives - Equipe physiopathologie et Thérapie des Désordres Vestibulaire, Centre National de la Recherche Scientifique, Aix Marseille Université, UMR 7260, Marseille, France
| | - Brahim Tighilet
- Laboratoire de Neurosciences Sensorielles et Cognitives - Equipe physiopathologie et Thérapie des Désordres Vestibulaire, Centre National de la Recherche Scientifique, Aix Marseille Université, UMR 7260, Marseille, France
| | - Christian Chabbert
- Laboratoire de Neurosciences Sensorielles et Cognitives - Equipe physiopathologie et Thérapie des Désordres Vestibulaire, Centre National de la Recherche Scientifique, Aix Marseille Université, UMR 7260, Marseille, France
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14
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Llorens J, Callejo A, Greguske EA, Maroto AF, Cutillas B, Martins-Lopes V. Physiological assesment of vestibular function and toxicity in humans and animals. Neurotoxicology 2018; 66:204-212. [PMID: 29428870 DOI: 10.1016/j.neuro.2018.02.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 01/29/2018] [Accepted: 02/04/2018] [Indexed: 01/15/2023]
Abstract
Physiological methods that can be similarly recorded in humans and animals have a major role in sensory toxicology, as they provide a bridge between human sensory perception data and the molecular and cellular data obtained in animal studies. Vestibular toxicity research lags well behind other sensory systems in many aspects, including the availability of methods for functional assessment in animals that could be robustly translated to human significance. Here we review the methods available for the assessment of vestibular function in both humans and laboratory animals, with an emphasis on their similarity or divergence, to highlight their potential utility for the predictive assessment of vestibular toxicity.
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Affiliation(s)
- Jordi Llorens
- Department de Ciències Fisiològiques, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08907 Hospitalet de Llobregat, Catalonia, Spain; Institute of Neuroscience, Universitat de Barcelona, Catalonia, Spain; Institut d'Investigació Biomèdica de Bellvitge, IDIBELL, 08907 Hospitalet de Llobregat, Catalonia, Spain.
| | - Angela Callejo
- Department de Ciències Fisiològiques, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08907 Hospitalet de Llobregat, Catalonia, Spain
| | - Erin A Greguske
- Department de Ciències Fisiològiques, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08907 Hospitalet de Llobregat, Catalonia, Spain; Institute of Neuroscience, Universitat de Barcelona, Catalonia, Spain; Institut d'Investigació Biomèdica de Bellvitge, IDIBELL, 08907 Hospitalet de Llobregat, Catalonia, Spain
| | - Alberto F Maroto
- Department de Ciències Fisiològiques, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08907 Hospitalet de Llobregat, Catalonia, Spain
| | - Blanca Cutillas
- Institut d'Investigació Biomèdica de Bellvitge, IDIBELL, 08907 Hospitalet de Llobregat, Catalonia, Spain; Department d'Infermeria Fonamental i Medicoquirúrgica, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08907 Hospitalet de Llobregat, Catalonia, Spain
| | - Vanessa Martins-Lopes
- Department de Ciències Fisiològiques, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08907 Hospitalet de Llobregat, Catalonia, Spain
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15
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Tighilet B, Péricat D, Frelat A, Cazals Y, Rastoldo G, Boyer F, Dumas O, Chabbert C. Adjustment of the dynamic weight distribution as a sensitive parameter for diagnosis of postural alteration in a rodent model of vestibular deficit. PLoS One 2017; 12:e0187472. [PMID: 29112981 PMCID: PMC5675415 DOI: 10.1371/journal.pone.0187472] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 10/20/2017] [Indexed: 11/18/2022] Open
Abstract
Vestibular disorders, by inducing significant posturo-locomotor and cognitive disorders, can significantly impair the most basic tasks of everyday life. Their precise diagnosis is essential to implement appropriate therapeutic countermeasures. Monitoring their evolution is also very important to validate or, on the contrary, to adapt the undertaken therapeutic actions. To date, the diagnosis methods of posturo-locomotor impairments are restricted to examinations that most often lack sensitivity and precision. In the present work we studied the alterations of the dynamic weight distribution in a rodent model of sudden and complete unilateral vestibular loss. We used a system of force sensors connected to a data analysis system to quantify in real time and in an automated way the weight bearing of the animal on the ground. We show here that sudden, unilateral, complete and permanent loss of the vestibular inputs causes a severe alteration of the dynamic ground weight distribution of vestibulo lesioned rodents. Characteristics of alterations in the dynamic weight distribution vary over time and follow the sequence of appearance and disappearance of the various symptoms that compose the vestibular syndrome. This study reveals for the first time that dynamic weight bearing is a very sensitive parameter for evaluating posturo-locomotor function impairment. Associated with more classical vestibular examinations, this paradigm can considerably enrich the methods for assessing and monitoring vestibular disorders. Systematic application of this type of evaluation to the dizzy or unstable patient could improve the detection of vestibular deficits and allow predicting better their impact on posture and walk. Thus it could also allow a better follow-up of the therapeutic approaches for rehabilitating gait and balance.
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Affiliation(s)
- Brahim Tighilet
- Aix Marseille Université, CNRS, Integrative and Adaptative Neurosciences UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France
- * E-mail: (CC); (BT)
| | - David Péricat
- Aix Marseille Université, CNRS, Integrative and Adaptative Neurosciences UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France
| | - Alais Frelat
- Aix Marseille Université, CNRS, Integrative and Adaptative Neurosciences UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France
| | - Yves Cazals
- Aix Marseille Université, CNRS, Integrative and Adaptative Neurosciences UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France
| | - Guillaume Rastoldo
- Aix Marseille Université, CNRS, Integrative and Adaptative Neurosciences UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France
| | - Florent Boyer
- Aix Marseille Université, CNRS, Integrative and Adaptative Neurosciences UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France
| | - Olivier Dumas
- Aix Marseille Université, CNRS, Integrative and Adaptative Neurosciences UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France
| | - Christian Chabbert
- Aix Marseille Université, CNRS, Integrative and Adaptative Neurosciences UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France
- * E-mail: (CC); (BT)
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16
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Cassel R, Bordiga P, Pericat D, Hautefort C, Tighilet B, Chabbert C. New mouse model for inducing and evaluating unilateral vestibular deafferentation syndrome. J Neurosci Methods 2017; 293:128-135. [PMID: 28911857 DOI: 10.1016/j.jneumeth.2017.09.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 09/06/2017] [Accepted: 09/11/2017] [Indexed: 11/19/2022]
Abstract
BACKGROUND Unilateral vestibular deafferentation syndrome (uVDS) holds a particular place in the vestibular pathology domain. Due to its suddenness, the violence of its symptoms that often result in emergency hospitalization, and its associated original neurophysiological properties, this syndrome is a major source of questioning for the otoneurology community. Also, its putative pathogenic causes remain to be determined. There is currently a strong medical need for the development of targeted and effective countermeasures to improve the therapeutic management of uVDS. NEW METHODS The present study reports the development of a new mouse model for inducing and evaluating uVDS. Both the method for generating controlled excitotoxic-type peripheral vestibular damages, through transtympanic administration of the glutamate receptors agonist kainate (TTK), and the procedure for evaluating the ensuing clinical signs are detailed. COMPARISON WITH EXISTING METHODS Through extensive analysis of the clinical symptoms characteristics, this new animal model provides the opportunity to better follow the temporal evolution of various uVDS specific symptoms, while better appreciating the different phases that composed this syndrome. RESULTS The uVDS evoked in the TTK mouse model displays two main phases distinguishable by their kinetics and amplitudes. Several parameters of the altered vestibular behaviour mimic those observed in the human syndrome. CONCLUSION This new murine model brings concrete information about how uVDS develops and how it affects global behaviour. In addition, it opens new opportunity to decipher the etiopathological substrate of this pathology by authorizing the use of genetically modified mouse models.
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Affiliation(s)
- R Cassel
- Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Intégratives et Adaptatives - Equipe physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France
| | - P Bordiga
- Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Intégratives et Adaptatives - Equipe physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France
| | - D Pericat
- Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Intégratives et Adaptatives - Equipe physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France
| | | | - B Tighilet
- Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Intégratives et Adaptatives - Equipe physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France
| | - C Chabbert
- Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Intégratives et Adaptatives - Equipe physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France.
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Péricat D, Farina A, Agavnian-Couquiaud E, Chabbert C, Tighilet B. Complete and irreversible unilateral vestibular loss: A novel rat model of vestibular pathology. J Neurosci Methods 2017; 283:83-91. [DOI: 10.1016/j.jneumeth.2017.04.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 03/26/2017] [Accepted: 04/01/2017] [Indexed: 01/10/2023]
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18
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Callejo A, Durochat A, Bressieux S, Saleur A, Chabbert C, Domènech Juan I, Llorens J, Gaboyard-Niay S. Dose-dependent cochlear and vestibular toxicity of trans-tympanic cisplatin in the rat. Neurotoxicology 2017; 60:1-9. [PMID: 28223157 DOI: 10.1016/j.neuro.2017.02.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 02/10/2017] [Accepted: 02/10/2017] [Indexed: 11/18/2022]
Abstract
In vivo studies are needed to study cisplatin ototoxicity and to evaluate candidate protective treatments. Rats and mice are the preferred species for toxicological and pharmacological pre-clinical research, but systemic administration of cisplatin causes high morbidity in these species. We hypothesized that trans-tympanic administration of cisplatin would provide a good model for studying its auditory and vestibular toxicity in the rat. Cisplatin was administered by the trans-tympanic route in one ear (50μl, 0.5-2mg/ml) of rats of both sexes and two different strains. Cochlear toxicity was corroborated by histological means. Vestibular toxicity was demonstrated by behavioral and histological analysis. Cisplatin concentrations were assessed in inner ear after trans-tympanic and i.v. administration. In all experiments, no lethality and only scant body weight loss were recorded. Cisplatin caused dose-dependent cochlear toxicity, as demonstrated by hair cell counts in the apical and middle turns of the cochlea, and vestibular toxicity, as demonstrated by behavioral analysis and hair cell counts in utricles. High concentrations of cisplatin were found in the inner ear after trans-tympanic administration. In comparison, i.v. administration resulted in lower inner ear concentrations. We conclude that trans-tympanic administration provides an easy, reproducible and safe model to study the cochlear and vestibular toxicity of cisplatin in the rat. This route of exposure may be useful to address particular questions on cisplatin induced ototoxicity and to test candidate protective treatments.
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Affiliation(s)
- Angela Callejo
- Departament de Ciències Fisiològiques, Universitat de Barcelona, 08907 L'Hospitalet de Llobregat, Catalonia, Spain; Unitat Funcional d'Otorinolaringologia i Al·lèrgia, Institut Universtiari Dexeus, 08028 Barcelona, Catalonia, Spain
| | | | | | | | | | - Ivan Domènech Juan
- Unitat Funcional d'Otorinolaringologia i Al·lèrgia, Institut Universtiari Dexeus, 08028 Barcelona, Catalonia, Spain; Institut de Neurociències, Universitat de Barcelona, Catalonia, Spain
| | - Jordi Llorens
- Departament de Ciències Fisiològiques, Universitat de Barcelona, 08907 L'Hospitalet de Llobregat, Catalonia, Spain; Institut de Neurociències, Universitat de Barcelona, Catalonia, Spain; Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), 08907 L'Hospitalet de Llobregat, Catalonia, Spain.
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Abstract
Future prospects continue to be strong for research using the rat as a model organism. New technology has enabled the proliferation of many new transgenic and knockout rat strains, the genomes of more than 40 rat strains have been sequenced, publications using the rat as a model continue to be produced at a steady rate, and discoveries of disease-associated genes and mechanisms from rat experiments abound, frequently with conservation of function between rats and humans. However, advances in genome technology have led to increasing insights into human disease directly from human genetic studies, pulling more and more researchers into the human genetics arena and placing funding for model organisms and their databases under threat. This, therefore, is a pivotal time for rat-based biomedical research - a timely moment to review progress and prospects - providing the inspiration for a new Special Collection focused on the impact of the model on translational science, launched in this issue of Disease Models & Mechanisms. What disease areas are most appropriate for research using rats? Why should the rat be favoured over other model organisms, and should the present levels of funding be continued? Which approaches should we expect to yield biologically and medically useful insights in the coming years? These are key issues that are addressed in the original Research Articles and reviews published in this Special Collection, and in this introductory Editorial. These exemplar articles serve as a landmark for the present status quo after a decade of major advances using the rat model and could help to guide the direction of rat research in the coming decade.
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Affiliation(s)
- Tim Aitman
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Paraminder Dhillon
- Disease Models & Mechanisms, The Company of Biologists, Bidder Building, Station Road, Histon, Cambridge CB24 9LF, UK
| | - Aron M Geurts
- Department of Physiology and Genome Editing Rat Resource Center, Medical College of Wisconsin, Milwaukee, WI 53226, USA
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