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Kokash J, Rumschlag JA, Razak KA. Cortical region-specific recovery of auditory temporal processing following noise-induced hearing loss. Neuroscience 2024; 560:143-157. [PMID: 39284433 DOI: 10.1016/j.neuroscience.2024.09.011] [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: 06/20/2024] [Revised: 08/21/2024] [Accepted: 09/04/2024] [Indexed: 09/30/2024]
Abstract
Noise-induced hearing loss (NIHL) studies have focused on the lemniscal auditory pathway, but little is known about how NIHL impacts different cortical regions. Here we compared response recovery trajectories in the auditory and frontal cortices (AC, FC) of mice following NIHL. We recorded EEG responses from awake mice (male n = 15, female n = 14) before and following NIHL (longitudinal design) to quantify event related potentials and gap-in-noise temporal processing. Hearing loss was verified by measuring the auditory brainstem response (ABR) before and at 1-, 10-, 23-, and 45-days after noise-exposure. Resting EEG, event related potentials (ERP) and auditory steady state responses (ASSR) were recorded at the same time-points after NIHL. The inter-trial phase coherence (ITPC) of the ASSR was measured to quantify the ability of AC and FC to synchronize responses to short gaps embedded in noise. Despite the absence of click-evoked ABRs up to 90 dB SPL and up to 45-days post-exposure, ERPs from the AC and FC showed full recovery in ∼ 50 % of the mice to pre-NIHL levels in both AC and FC. The ASSR ITPC was reduced following NIHL in AC and FC in all the mice on day 1 after NIHL. The AC showed full recovery of ITPC over 45-days. Despite ERP amplitude recovery, the FC does not show recovery of ASSR ITPC. These results indicate post-NIHL plasticity with similar response amplitude recovery across AC and FC, but cortical region-specific trajectories in temporal processing recovery.
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Affiliation(s)
- J Kokash
- Graduate Neuroscience Program, University of California, Riverside, United States
| | - J A Rumschlag
- Graduate Neuroscience Program, University of California, Riverside, United States
| | - K A Razak
- Graduate Neuroscience Program, University of California, Riverside, United States; Department of Psychology, University of California, Riverside, United States.
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Lutze RD, Ingersoll MA, Thotam A, Joseph A, Fernandes J, Teitz T. ERK1/2 Inhibition via the Oral Administration of Tizaterkib Alleviates Noise-Induced Hearing Loss While Tempering down the Immune Response. Int J Mol Sci 2024; 25:6305. [PMID: 38928015 PMCID: PMC11204379 DOI: 10.3390/ijms25126305] [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: 05/17/2024] [Revised: 06/02/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024] Open
Abstract
Noise-induced hearing loss (NIHL) is a major cause of hearing impairment and is linked to dementia and mental health conditions, yet no FDA-approved drugs exist to prevent it. Downregulating the mitogen-activated protein kinase (MAPK) cellular pathway has emerged as a promising approach to attenuate NIHL, but the molecular targets and the mechanism of protection are not fully understood. Here, we tested specifically the role of the kinases ERK1/2 in noise otoprotection using a newly developed, highly specific ERK1/2 inhibitor, tizaterkib, in preclinical animal models. Tizaterkib is currently being tested in phase 1 clinical trials for cancer treatment and has high oral bioavailability and low predicted systemic toxicity in mice and humans. In this study, we performed dose-response measurements of tizaterkib's efficacy against permanent NIHL in adult FVB/NJ mice, and its minimum effective dose (0.5 mg/kg/bw), therapeutic index (>50), and window of opportunity (<48 h) were determined. The drug, administered orally twice daily for 3 days, 24 h after 2 h of 100 dB or 106 dB SPL noise exposure, at a dose equivalent to what is prescribed currently for humans in clinical trials, conferred an average protection of 20-25 dB SPL in both female and male mice. The drug shielded mice from the noise-induced synaptic damage which occurs following loud noise exposure. Equally interesting, tizaterkib was shown to decrease the number of CD45- and CD68-positive immune cells in the mouse cochlea following noise exposure. This study suggests that repurposing tizaterkib and the ERK1/2 kinases' inhibition could be a promising strategy for the treatment of NIHL.
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Affiliation(s)
- Richard D. Lutze
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA; (R.D.L.); (M.A.I.); (A.T.); (A.J.); (J.F.)
| | - Matthew A. Ingersoll
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA; (R.D.L.); (M.A.I.); (A.T.); (A.J.); (J.F.)
| | - Alena Thotam
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA; (R.D.L.); (M.A.I.); (A.T.); (A.J.); (J.F.)
| | - Anjali Joseph
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA; (R.D.L.); (M.A.I.); (A.T.); (A.J.); (J.F.)
| | - Joshua Fernandes
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA; (R.D.L.); (M.A.I.); (A.T.); (A.J.); (J.F.)
| | - Tal Teitz
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA; (R.D.L.); (M.A.I.); (A.T.); (A.J.); (J.F.)
- The Scintillon Research Institute, San Diego, CA 92121, USA
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Lutze RD, Ingersoll MA, Kelmann RG, Teitz T. Trametinib, a MEK1/2 Inhibitor, Protects Mice from Cisplatin- and Noise-Induced Hearing Loss. Pharmaceuticals (Basel) 2024; 17:735. [PMID: 38931403 PMCID: PMC11206450 DOI: 10.3390/ph17060735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Revised: 05/30/2024] [Accepted: 06/04/2024] [Indexed: 06/28/2024] Open
Abstract
Hearing loss is one of the most common types of disability; however, there is only one FDA-approved drug to prevent any type of hearing loss. Treatment with the highly effective chemotherapy agent, cisplatin, and exposure to high-decibel noises are two of the most common causes of hearing loss. The mitogen-activated protein kinase (MAPK) pathway, a phosphorylation cascade consisting of RAF, MEK1/2, and ERK1/2, has been implicated in both types of hearing loss. Pharmacologically inhibiting BRAF or ERK1/2 is protective against noise- and cisplatin-induced hearing loss in multiple mouse models. Trametinib, a MEK1/2 inhibitor, protects from cisplatin-induced outer hair cell death in mouse cochlear explants; however, to the best of our knowledge, inhibiting MEK1/2 has not yet been shown to be protective against hearing loss in vivo. In this study, we demonstrate that trametinib protects against cisplatin-induced hearing loss in a translationally relevant mouse model and does not interfere with cisplatin's tumor-killing efficacy in cancer cell lines. Higher doses of trametinib were toxic to mice when combined with cisplatin, but lower doses of the drug were protective against hearing loss without any known toxicity. Trametinib also protected mice from noise-induced hearing loss and synaptic damage. This study shows that MEK1/2 inhibition protects against both insults of hearing loss, as well as that targeting all three kinases in the MAPK pathway protects mice from cisplatin- and noise-induced hearing loss.
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Affiliation(s)
- Richard D. Lutze
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA; (R.D.L.); (M.A.I.); (R.G.K.)
| | - Matthew A. Ingersoll
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA; (R.D.L.); (M.A.I.); (R.G.K.)
| | - Regina G. Kelmann
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA; (R.D.L.); (M.A.I.); (R.G.K.)
| | - Tal Teitz
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA; (R.D.L.); (M.A.I.); (R.G.K.)
- The Scintillon Research Institute, San Diego, CA 92121, USA
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Lutze RD, Ingersoll MA, Kelmann RG, Teitz T. FDA-Approved MEK1/2 Inhibitor, Trametinib, Protects Mice from Cisplatin and Noise-Induced Hearing Loss. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.20.595056. [PMID: 38826449 PMCID: PMC11142120 DOI: 10.1101/2024.05.20.595056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Hearing loss is one of the most common types of disability; however, there is only one FDA-approved drug to prevent any type of hearing loss. Treatment with the highly effective chemotherapy agent, cisplatin, and exposure to high decibel noises are two of the most common causes of hearing loss. The mitogen activated protein kinase (MAPK) pathway, a phosphorylation cascade consisting of RAF, MEK1/2, and ERK1/2, has been implicated in both types of hearing loss. Pharmacologically inhibiting BRAF or ERK1/2 is protective from noise and cisplatin-induced hearing loss in multiple mouse models. Trametinib, a MEK1/2 inhibitor, protects from cisplatin induced outer hair cell death in mouse cochlear explants; however, to the best of our knowledge, inhibiting MEK1/2 has not yet been shown to be protective from hearing loss in vivo. In this study, we demonstrate that trametinib protects from cisplatin-induced hearing loss in a translationally relevant mouse model and does not interfere with cisplatin's tumor killing efficacy in cancer cell lines. Higher doses of trametinib were toxic to mice when combined with cisplatin but lower doses of the drug were protective from hearing loss without any known toxicity. Trametinib also protected mice from noise-induced hearing loss and synaptic damage. This study shows that MEK1/2 inhibition protects from both insults of hearing loss and that targeting all three kinases in the MAPK pathway protect from cisplatin and noise-induced hearing loss in mice.
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Affiliation(s)
- Richard D. Lutze
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA
| | - Matthew A. Ingersoll
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA
| | - Regina G. Kelmann
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA
| | - Tal Teitz
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA
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Sailor-Longsworth E, Lutze RD, Ingersoll MA, Kelmann RG, Ly K, Currier D, Chen T, Zuo J, Teitz T. Oseltamivir (Tamiflu), a Commonly Prescribed Antiviral Drug, Mitigates Hearing Loss in Mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.06.592815. [PMID: 38765999 PMCID: PMC11100672 DOI: 10.1101/2024.05.06.592815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Hearing loss affects up to 10% of all people worldwide, but currently there is only one FDA-approved drug for its prevention in a subgroup of cisplatin-treated pediatric patients. Here, we performed an unbiased screen of 1,300 FDA-approved drugs for protection against cisplatin-induced cell death in an inner ear cell line, and identified oseltamivir phosphate (brand name Tamiflu), a common influenza antiviral drug, as a top candidate. Oseltamivir phosphate was found to be otoprotective by oral delivery in multiple established cisplatin and noise exposure mouse models. The drug conferred permanent hearing protection of 15-25 dB SPL for both female and male mice. Oseltamivir treatment reduced in mice outer hair cells death after cisplatin treatment and mitigated cochlear synaptopathy after noise exposure. A potential binding protein, ERK1/2, associated with inflammation, was shown to be activated with cisplatin treatment and reduced by oseltamivir cotreatment in cochlear explants. Importantly, the number of infiltrating immune cells to the cochleae in mice post noise exposure, were significantly reduced with oseltamivir treatment, suggesting an anti-inflammatory mechanism of action. Our results support oseltamivir, a widespread drug for influenza with low side effects, as a promising otoprotective therapeutic candidate in both cisplatin chemotherapy and traumatic noise exposure.
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Affiliation(s)
- Emma Sailor-Longsworth
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA
| | - Richard D. Lutze
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA
| | - Matthew A. Ingersoll
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA
| | - Regina G. Kelmann
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA
| | - Kristina Ly
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA
| | - Duane Currier
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, Memphis, TN, 38105, USA
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, Memphis, TN, 38105, USA
| | - Jian Zuo
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, NE 68178, USA
| | - Tal Teitz
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE 68178, USA
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Avcı AU. Hearing Loss in Space Flights: A Review of Noise Regulations and Previous Outcomes. J Int Adv Otol 2024; 20:171-174. [PMID: 39158074 PMCID: PMC11114227 DOI: 10.5152/iao.2024.231434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 01/03/2024] [Indexed: 08/20/2024] Open
Abstract
Noise is the primary cause of hearing loss during space flight. Throughout every phase of flight, particularly during launch, a significant amount of noise is generated and transferred via the vehicle's structure to the places inhabited by the crew. The results of the previous studies provide insights into space flights that may have significant effects on hearing loss. Certain precautions must be taken to ensure the habitability of the spacecraft and prevent potential hearing loss in astronauts or space flight participants.
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Affiliation(s)
- Ahmet Uğur Avcı
- Department of Aerospace Medicine, Gülhane Training and Research Hospital, Ankara, Turkey
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Bovee S, Klump GM, Pyott SJ, Sielaff C, Köppl C. Cochlear Ribbon Synapses in Aged Gerbils. Int J Mol Sci 2024; 25:2738. [PMID: 38473985 DOI: 10.3390/ijms25052738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 02/15/2024] [Accepted: 02/21/2024] [Indexed: 03/14/2024] Open
Abstract
In mammalian hearing, type-I afferent auditory nerve fibers comprise the basis of the afferent auditory pathway. They are connected to inner hair cells of the cochlea via specialized ribbon synapses. Auditory nerve fibers of different physiological types differ subtly in their synaptic location and morphology. Low-spontaneous-rate auditory nerve fibers typically connect on the modiolar side of the inner hair cell, while high-spontaneous-rate fibers are typically found on the pillar side. In aging and noise-damaged ears, this fine-tuned balance between auditory nerve fiber populations can be disrupted and the functional consequences are currently unclear. Here, using immunofluorescent labeling of presynaptic ribbons and postsynaptic glutamate receptor patches, we investigated changes in synaptic morphology at three different tonotopic locations along the cochlea of aging gerbils compared to those of young adults. Quiet-aged gerbils showed about 20% loss of afferent ribbon synapses. While the loss was random at apical, low-frequency cochlear locations, at the basal, high-frequency location it almost exclusively affected the modiolar-located synapses. The subtle differences in volumes of pre- and postsynaptic elements located on the inner hair cell's modiolar versus pillar side were unaffected by age. This is consistent with known physiology and suggests a predominant, age-related loss in the low-spontaneous-rate auditory nerve population in the cochlear base, but not the apex.
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Affiliation(s)
- Sonny Bovee
- Department of Neuroscience, School of Medicine and Health Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
| | - Georg M Klump
- Department of Neuroscience, School of Medicine and Health Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
- Cluster of Excellence "Hearing4all", Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
- Research Centre Neurosensory Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
| | - Sonja J Pyott
- Department of Otorhinolaryngology/Head and Neck Surgery, University Medical Center Groningen, University of Groningen, P.O. Box 30.001, 9700 RB Groningen, The Netherlands
| | - Charlotte Sielaff
- Department of Neuroscience, School of Medicine and Health Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
- Fraunhofer Institute for Toxicology and Experimental Medicine (ITEM), 30625 Hannover, Germany
| | - Christine Köppl
- Department of Neuroscience, School of Medicine and Health Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
- Cluster of Excellence "Hearing4all", Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
- Research Centre Neurosensory Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
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Penn C, Mayilsamy K, Zhu XX, Bauer MA, Mohapatra SS, Frisina RD, Mohapatra S. A mouse model of repeated traumatic brain injury-induced hearing impairment: Early cochlear neurodegeneration in the absence of hair cell loss. Hear Res 2023; 436:108832. [PMID: 37364367 DOI: 10.1016/j.heares.2023.108832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/05/2023] [Accepted: 06/13/2023] [Indexed: 06/28/2023]
Abstract
PURPOSE Traumatic Brain Injury (TBI) is a major cause of death and disability worldwide. Mounting evidence suggests that even mild TBI injuries, which comprise >75% of all TBIs, can cause chronic post-concussive neurological symptoms, especially when experienced repetitively (rTBI). The most common post-concussive symptoms include auditory dysfunction in the form of hearing loss, tinnitus, or impaired auditory processing, which can occur even in the absence of direct damage to the auditory system at the time of injury. The mechanism by which indirect damage causes loss of auditory function is poorly understood, and treatment is currently limited to symptom management rather than preventative care. We reasoned that secondary injury mechanisms, such as inflammation, may lead to damage of the inner ear and parts of the brain used for hearing after rTBI. Herein, we established a model of indirect damage to the auditory system induced by rTBI and characterized the pathology of hearing loss. METHODS We established a mouse model of rTBI in order to determine a timeline of auditory pathology following multiple mild injuries. Mice were subject to controlled cortical impact at the skull midline once every 48 h, for a total of 5 hits. Auditory function was assessed via the auditory brainstem response (ABR) at various timepoints post injury. Brain and cochleae were collected to establish a timeline of cellular pathology. RESULTS We observed increased ABR thresholds and decreased (ABR) P1 amplitudes in rTBI vs sham animals at 14 days post-impact (dpi). This effect persisted for up to 60 days (dpi). Auditory temporal processing was impaired beginning at 30 dpi. Spiral ganglion degeneration was evident at 14 dpi. No loss of hair cells was detected at this time, suggesting that neuronal loss is one of the earliest notable events in hearing loss caused by this type of rTBI. CONCLUSIONS We conclude that rTBI results in chronic auditory dysfunction via damage to the spiral ganglion which occurs in the absence of any reduction in hair cell number. This suggests early neuronal damage that may be caused by systemic mechanisms similar to those leading to the spread of neuronal death in the brain following TBI. This TBI-hearing loss model provides an important first step towards identifying therapeutic targets to attenuate damage to the auditory system following head injury.
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Affiliation(s)
- Courtney Penn
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; James A Haley VA Hospital, Tampa, FL 33612, USA
| | - Karthick Mayilsamy
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; James A Haley VA Hospital, Tampa, FL 33612, USA
| | - Xiao Xia Zhu
- Department of Medical Engineering, College of Engineering and Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Mark A Bauer
- Department of Medical Engineering, College of Engineering and Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Shyam S Mohapatra
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; James A Haley VA Hospital, Tampa, FL 33612, USA
| | - Robert D Frisina
- Department of Medical Engineering, College of Engineering and Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA.
| | - Subhra Mohapatra
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; James A Haley VA Hospital, Tampa, FL 33612, USA.
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Wagner EL, Im JS, Sala S, Nakahata MI, Imbery TE, Li S, Chen D, Nimchuk K, Noy Y, Archer DW, Xu W, Hashisaki G, Avraham KB, Oakes PW, Shin JB. Repair of noise-induced damage to stereocilia F-actin cores is facilitated by XIRP2 and its novel mechanosensor domain. eLife 2023; 12:e72681. [PMID: 37294664 PMCID: PMC10259482 DOI: 10.7554/elife.72681] [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: 08/01/2021] [Accepted: 05/17/2023] [Indexed: 06/11/2023] Open
Abstract
Prolonged exposure to loud noise has been shown to affect inner ear sensory hair cells in a variety of deleterious manners, including damaging the stereocilia core. The damaged sites can be visualized as 'gaps' in phalloidin staining of F-actin, and the enrichment of monomeric actin at these sites, along with an actin nucleator and crosslinker, suggests that localized remodeling occurs to repair the broken filaments. Herein, we show that gaps in mouse auditory hair cells are largely repaired within 1 week of traumatic noise exposure through the incorporation of newly synthesized actin. We provide evidence that Xin actin binding repeat containing 2 (XIRP2) is required for the repair process and facilitates the enrichment of monomeric γ-actin at gaps. Recruitment of XIRP2 to stereocilia gaps and stress fiber strain sites in fibroblasts is force-dependent, mediated by a novel mechanosensor domain located in the C-terminus of XIRP2. Our study describes a novel process by which hair cells can recover from sublethal hair bundle damage and which may contribute to recovery from temporary hearing threshold shifts and the prevention of age-related hearing loss.
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Affiliation(s)
- Elizabeth L Wagner
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
- Department of Biochemistry & Molecular Genetics, University of VirginiaCharlottesvilleUnited States
| | - Jun-Sub Im
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
| | - Stefano Sala
- Department of Cell & Molecular Physiology, Stritch School of Medicine, Loyola University ChicagoChicagoUnited States
| | - Maura I Nakahata
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
| | - Terence E Imbery
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
- Department of Otolaryngology-Head & Neck Surgery, University of VirginiaCharlottesvilleUnited States
| | - Sihan Li
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
- Department of Biochemistry & Molecular Genetics, University of VirginiaCharlottesvilleUnited States
| | - Daniel Chen
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
| | - Katherine Nimchuk
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
| | - Yael Noy
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv UniversityTel AvivIsrael
| | - David W Archer
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
| | - Wenhao Xu
- Genetically Engineered Murine Model (GEMM) Core, University of VirginiaCharlottesvilleUnited States
| | - George Hashisaki
- Department of Otolaryngology-Head & Neck Surgery, University of VirginiaCharlottesvilleUnited States
| | - Karen B Avraham
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv UniversityTel AvivIsrael
| | - Patrick W Oakes
- Department of Cell & Molecular Physiology, Stritch School of Medicine, Loyola University ChicagoChicagoUnited States
| | - Jung-Bum Shin
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
- Department of Biochemistry & Molecular Genetics, University of VirginiaCharlottesvilleUnited States
- Department of Otolaryngology-Head & Neck Surgery, University of VirginiaCharlottesvilleUnited States
- Department of Cell Biology, University of VirginiaCharlottesvilleUnited States
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Mauriac SA, Peineau T, Zuberi A, Lutz C, Géléoc GSG. Loss of Pex1 in Inner Ear Hair Cells Contributes to Cochlear Synaptopathy and Hearing Loss. Cells 2022; 11:cells11243982. [PMID: 36552747 PMCID: PMC9777190 DOI: 10.3390/cells11243982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 12/04/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022] Open
Abstract
Peroxisome Biogenesis Disorders (PBD) and Zellweger syndrome spectrum disorders (ZSD) are rare genetic multisystem disorders that include hearing impairment and are associated with defects in peroxisome assembly, function, or both. Mutations in 13 peroxin (PEX) genes have been found to cause PBD-ZSD with ~70% of patients harboring mutations in PEX1. Limited research has focused on the impact of peroxisomal disorders on auditory function. As sensory hair cells are particularly vulnerable to metabolic changes, we hypothesize that mutations in PEX1 lead to oxidative stress affecting hair cells of the inner ear, subsequently resulting in hair cell degeneration and hearing loss. Global deletion of the Pex1 gene is neonatal lethal in mice, impairing any postnatal studies. To overcome this limitation, we created conditional knockout mice (cKO) using Gfi1Creor VGlut3Cre expressing mice crossed to floxed Pex1 mice to allow for selective deletion of Pex1 in the hair cells of the inner ear. We find that Pex1 excision in inner hair cells (IHCs) leads to progressive hearing loss associated with significant decrease in auditory brainstem responses (ABR), specifically ABR wave I amplitude, indicative of synaptic defects. Analysis of IHC synapses in cKO mice reveals a decrease in ribbon synapse volume and functional alterations in exocytosis. Concomitantly, we observe a decrease in peroxisomal number, indicative of oxidative stress imbalance. Taken together, these results suggest a critical function of Pex1 in development and maturation of IHC-spiral ganglion synapses and auditory function.
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Affiliation(s)
- Stephanie A. Mauriac
- Department of Otolaryngology, Boston Children’s Hospital, Boston, MA 02115, USA
- Kirby Neurobiology Center, Harvard Medical School, Boston, MA 02115, USA
| | - Thibault Peineau
- Department of Otolaryngology, Boston Children’s Hospital, Boston, MA 02115, USA
- Kirby Neurobiology Center, Harvard Medical School, Boston, MA 02115, USA
| | - Aamir Zuberi
- Rare Disease Translational Center, The Jackson Laboratory, Bar Harbor, ME 04609, USA
- Technology Evaluation and Development Research Laboratory, The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Cathleen Lutz
- Rare Disease Translational Center, The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Gwénaëlle S. G. Géléoc
- Department of Otolaryngology, Boston Children’s Hospital, Boston, MA 02115, USA
- Kirby Neurobiology Center, Harvard Medical School, Boston, MA 02115, USA
- Correspondence: ; Tel.: +1-617-919-4061
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Li Y, Yu H, Zhou X, Jin L, Li W, Li GL, Shen X. Multiple Sevoflurane Exposures During the Neonatal Period Cause Hearing Impairment and Loss of Hair Cell Ribbon Synapses in Adult Mice. Front Neurosci 2022; 16:945277. [PMID: 35911996 PMCID: PMC9329801 DOI: 10.3389/fnins.2022.945277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 06/24/2022] [Indexed: 11/13/2022] Open
Abstract
Objectives This study aims to investigate the effects of multiple sevoflurane exposures in neonatal mice on hearing function in the later life and explores the underlying mechanisms and protective strategies. Materials and Methods Neonatal Kunming mice were exposed to sevoflurane for 3 days. Auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) tests, immunofluorescence, patch-clamp recording, and quantitative real-time PCR were performed to observe hearing function, hair cells, ribbon synapses, nerve fibers, spiral ganglion neurons, and oxidative stress. Results Compared to control group, multiple sevoflurane exposures during the neonatal time significantly elevated ABR thresholds at 8 kHz (35.42 ± 1.57 vs. 41.76 ± 1.97 dB, P = 0.0256), 16 kHz (23.33 ± 1.28 vs. 33.53 ± 2.523 dB, P = 0.0012), 24 kHz (30.00 ± 2.04 vs. 46.76 ± 3.93 dB, P = 0.0024), and 32 kHz (41.25 ± 2.31 vs. 54.41 ± 2.94 dB, P = 0.0028) on P30, caused ribbon synapse loss on P15 (13.10 ± 0.43 vs. 10.78 ± 0.52, P = 0.0039) and P30 (11.24 ± 0.56 vs. 8.50 ± 0.84, P = 0.0141), and degenerated spiral ganglion neuron (SGN) nerve fibers on P30 (110.40 ± 16.23 vs. 55.04 ± 8.13, P = 0.0073). In addition, the Vhalf of calcium current become more negative (−21.99 ± 0.70 vs. −27.17 ± 0.60 mV, P < 0.0001), exocytosis was reduced (105.40 ± 19.97 vs. 59.79 ± 10.60 fF, P < 0.0001), and Lpo was upregulated (P = 0.0219) in sevoflurane group than those in control group. N-acetylcysteine (NAC) reversed hearing impairment induced by sevoflurane. Conclusion The findings suggest that multiple sevoflurane exposures during neonatal time may cause hearing impairment in adult mice. The study also demonstrated that elevated oxidative stress led to ribbon synapses impairment and SGN nerve fibers degeneration, and the interventions of antioxidants alleviated the sevoflurane-induced hearing impairment.
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Affiliation(s)
- Yufeng Li
- Department of Anesthesiology, Eye & ENT Hospital, Fudan University, Shanghai, China
| | - Huiqian Yu
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China
| | - Xuehua Zhou
- Department of Anesthesiology, Eye & ENT Hospital, Fudan University, Shanghai, China
| | - Lin Jin
- Department of Anesthesiology, Eye & ENT Hospital, Fudan University, Shanghai, China
| | - Wen Li
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China
| | - Geng-Lin Li
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
- *Correspondence: Geng-Lin Li,
| | - Xia Shen
- Department of Anesthesiology, Eye & ENT Hospital, Fudan University, Shanghai, China
- Xia Shen,
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Shehabi AM, Prendergast G, Plack CJ. The Relative and Combined Effects of Noise Exposure and Aging on Auditory Peripheral Neural Deafferentation: A Narrative Review. Front Aging Neurosci 2022; 14:877588. [PMID: 35813954 PMCID: PMC9260498 DOI: 10.3389/fnagi.2022.877588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Animal studies have shown that noise exposure and aging cause a reduction in the number of synapses between low and medium spontaneous rate auditory nerve fibers and inner hair cells before outer hair cell deterioration. This noise-induced and age-related cochlear synaptopathy (CS) is hypothesized to compromise speech recognition at moderate-to-high suprathreshold levels in humans. This paper evaluates the evidence on the relative and combined effects of noise exposure and aging on CS, in both animals and humans, using histopathological and proxy measures. In animal studies, noise exposure seems to result in a higher proportion of CS (up to 70% synapse loss) compared to aging (up to 48% synapse loss). Following noise exposure, older animals, depending on their species, seem to either exhibit significant or little further synapse loss compared to their younger counterparts. In humans, temporal bone studies suggest a possible age- and noise-related auditory nerve fiber loss. Based on the animal data obtained from different species, we predict that noise exposure may accelerate age-related CS to at least some extent in humans. In animals, noise-induced and age-related CS in separation have been consistently associated with a decreased amplitude of wave 1 of the auditory brainstem response, reduced middle ear muscle reflex strength, and degraded temporal processing as demonstrated by lower amplitudes of the envelope following response. In humans, the individual effects of noise exposure and aging do not seem to translate clearly into deficits in electrophysiological, middle ear muscle reflex, and behavioral measures of CS. Moreover, the evidence on the combined effects of noise exposure and aging on peripheral neural deafferentation in humans using electrophysiological and behavioral measures is even more sparse and inconclusive. Further research is necessary to establish the individual and combined effects of CS in humans using temporal bone, objective, and behavioral measures.
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Affiliation(s)
- Adnan M. Shehabi
- Manchester Centre for Audiology and Deafness, University of Manchester, Manchester, United Kingdom
- Department of Audiology and Speech Therapy, Birzeit University, Birzeit, Palestine
| | - Garreth Prendergast
- Manchester Centre for Audiology and Deafness, University of Manchester, Manchester, United Kingdom
| | - Christopher J. Plack
- Manchester Centre for Audiology and Deafness, University of Manchester, Manchester, United Kingdom
- Department of Psychology, Lancaster University, Lancaster, United Kingdom
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Mahdi P, Pourbakht A, Karimi Yazdi A, Rabbani Anari M, Pirhajati Mahabadi V, Kamali M. Metabotropic glutamate receptor: A new possible therapeutic target for cochlear synaptopathy. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2022; 25:75-83. [PMID: 35656439 PMCID: PMC9118270 DOI: 10.22038/ijbms.2021.59970.13296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 11/24/2021] [Indexed: 11/08/2022]
Abstract
Objectives Cochlear synaptopathy is a common cause of auditory disorders in which glutamate over-activation occurs. Modulating glutamatergic pathways has been proposed to down-regulate post-synaptic excitation. Materials and Methods 12-guinea pigs as sham and test groups were exposed to a 4-kHz noise at 104 dB SPL, for 2 hr. Pre-exposure intra-tympanic injection with LY354740 and normal saline 9% was applied in the test and sham groups. The amplitude growth of ABR-wave-I and wave-III latency shift with noise were considered in pre- and post-exposure times. The synapses were observed by transmission electron-microscopy. Results ABR thresholds recovered 1-week post-exposure in both groups. The reduction of wave-I amplitude at 4, 6, and 8 kHz were statistically different between pre- and 1- day post-exposure and recovered mostly in the sham group. The amount of latency shift in masked ABR was different between pre- and all post-exposure, and the response could not be detected at higher than 50 dB SL noise. However, the response detectability increased to 60 dB SL noise, and the significance of differences between pre- and post-exposure persisted only at the high level of noise in the test group. In electron-microscopy of sham samples, the size of the ribbon was larger, spherical with an irregularity, and hollow. The post-synaptic density was thicker and missed its flat orientation. Conclusion The higher slope of the ABR-wave I amplitude, the more tolerance of noise in masked ABR, concomitant with the histological finding that revealed less synaptic damage, confirmed the therapeutic effect of LY354740 in cochlear synaptopathy.
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Affiliation(s)
- Parvane Mahdi
- Department of Audiology, School of Rehabilitation Sciences, Iran University of Medical Sciences. Tehran, Iran
| | - Akram Pourbakht
- Department of Audiology, School of Rehabilitation Sciences, Iran University of Medical Sciences. Tehran, Iran,Rehabilitation Research Center, Department of Audiology, School of Rehabilitation Sciences, Iran University of Medical Sciences. Tehran, Iran,Corresponding author: Akram Pourbakht. Rehabilitation Research Center, Department of Audiology, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran. Tel: +98-21-22250541;
| | - Alireza Karimi Yazdi
- Department of Otorhinolaryngology-Head and Neck Surgery, Imam Khomeini Educational Hospital Complex, Tehran University of Medical Sciences. Tehran, Iran
| | - Mahtab Rabbani Anari
- Otorhinolaryngology Research Center, Amir-Alam Educational Complex, Tehran University of Medical Sciences. Tehran, Iran
| | - Vahid Pirhajati Mahabadi
- Department of Neurosciences, School of Medicine. Iran University of Medical Sciences. Tehran, Iran
| | - Mohammad Kamali
- Department of Rehabilitation Management, School of Rehabilitation Sciences, Iran University of Medical Sciences. Tehran, Iran
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14
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Boero LE, Payne S, Gómez-Casati ME, Rutherford MA, Goutman JD. Noise Exposure Potentiates Exocytosis From Cochlear Inner Hair Cells. Front Synaptic Neurosci 2021; 13:740368. [PMID: 34658832 PMCID: PMC8511412 DOI: 10.3389/fnsyn.2021.740368] [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: 07/13/2021] [Accepted: 09/10/2021] [Indexed: 11/19/2022] Open
Abstract
Noise-induced hearing loss has gained relevance as one of the most common forms of hearing impairment. The anatomical correlates of hearing loss, principally cell damage and/or death, are relatively well-understood histologically. However, much less is known about the physiological aspects of damaged, surviving cells. Here we addressed the functional consequences of noise exposure on the capacity of inner hair cells (IHCs) to release synaptic vesicles at synapses with spiral ganglion neurons (SGNs). Mice of either sex at postnatal day (P) 15–16 were exposed to 1–12 kHz noise at 120 dB sound pressure level (SPL), for 1 h. Exocytosis was measured by tracking changes in membrane capacitance (ΔCm) from IHCs of the apical cochlea. Upon IHC depolarization to different membrane potentials, ΔCm showed the typical bell-shaped curve that mirrors the voltage dependence of Ca2+ influx, in both exposed and unexposed cells. Surprisingly, from IHCs at 1-day after exposure (d.a.e.), we found potentiation of exocytosis at the peak of the bell-shaped curve. The increase in exocytosis was not accompanied by changes in whole-cell Ca2+ influx, suggesting a modification in coupling between Ca2+ channels and synaptic vesicles. Consistent with this notion, noise exposure also changed the Ca2+-dependence of exocytosis from linear to supralinear. Noise exposure did not cause loss of IHCs, but did result in a small reduction in the number of IHC-SGN synapses at 1-d.a.e. which recovered by 14-d.a.e. In contrast, a strong reduction in auditory brainstem response wave-I amplitude (representing synchronous firing of SGNs) and distortion product otoacoustic emissions (reflecting outer hair cell function) indicated a profound hearing loss at 1- and 14-d.a.e. To determine the role of glutamate release in the noise-induced potentiation of exocytosis, we evaluated vesicular glutamate transporter-3 (Vglut3) knock-out (KO) mice. Unlike WT, IHCs from Vglut3KO mice showed a noise-induced reduction in ΔCm and Ca2+ influx with no change in the Ca2+-dependence of exocytosis. Together, these results indicate that traumatic noise exposure triggers changes of IHC synaptic function including a Vglut3-dependent potentiation of exocytosis.
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Affiliation(s)
- Luis E Boero
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres" (INGEBI), Buenos Aires, Argentina.,Instituto de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Shelby Payne
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO, United States
| | | | - Mark A Rutherford
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO, United States
| | - Juan D Goutman
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres" (INGEBI), Buenos Aires, Argentina
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15
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Jongkamonwiwat N, Ramirez MA, Edassery S, Wong ACY, Yu J, Abbott T, Pak K, Ryan AF, Savas JN. Noise Exposures Causing Hearing Loss Generate Proteotoxic Stress and Activate the Proteostasis Network. Cell Rep 2020; 33:108431. [PMID: 33238128 PMCID: PMC7722268 DOI: 10.1016/j.celrep.2020.108431] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 09/24/2020] [Accepted: 11/04/2020] [Indexed: 12/20/2022] Open
Abstract
Exposure to excessive sound causes noise-induced hearing loss through complex mechanisms and represents a common and unmet neurological condition. We investigate how noise insults affect the cochlea with proteomics and functional assays. Quantitative proteomics reveals that exposure to loud noise causes proteotoxicity. We identify and confirm hundreds of proteins that accumulate, including cytoskeletal proteins, and several nodes of the proteostasis network. Transcriptomic analysis reveals that a subset of the genes encoding these proteins also increases acutely after noise exposure, including numerous proteasome subunits. Global cochlear protein ubiquitylation levels build up after exposure to excess noise, and we map numerous posttranslationally modified lysines residues. Several collagen proteins decrease in abundance, and Col9a1 specifically localizes to pillar cell heads. After two weeks of recovery, the cochlea selectively elevates the abundance of the protein synthesis machinery. We report that overstimulation of the auditory system drives a robust cochlear proteotoxic stress response.
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Affiliation(s)
- Nopporn Jongkamonwiwat
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Miguel A Ramirez
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Seby Edassery
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Ann C Y Wong
- Departments of Surgery and Neuroscience, University of California San Diego and Veterans Administration Medical Center, La Jolla, CA 92093, USA; Translational Neuroscience Facility, Department of Physiology, NSW Australia, Sydney, NSW 2052, Australia
| | - Jintao Yu
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Tirzah Abbott
- Northwestern University Atomic and Nanoscale Characterization Experimental (NUANCE) Center, Northwestern University, Evanston, IL 60208, USA
| | - Kwang Pak
- Departments of Surgery and Neuroscience, University of California San Diego and Veterans Administration Medical Center, La Jolla, CA 92093, USA
| | - Allen F Ryan
- Departments of Surgery and Neuroscience, University of California San Diego and Veterans Administration Medical Center, La Jolla, CA 92093, USA
| | - Jeffrey N Savas
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
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16
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Patel S, Shah L, Dang N, Tan X, Almudevar A, White PM. SIRT3 promotes auditory function in young adult FVB/nJ mice but is dispensable for hearing recovery after noise exposure. PLoS One 2020; 15:e0235491. [PMID: 32658908 PMCID: PMC7357743 DOI: 10.1371/journal.pone.0235491] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 06/16/2020] [Indexed: 01/08/2023] Open
Abstract
Noise-induced hearing loss (NIHL) affects millions of people worldwide and presents a large social and personal burden. Pharmacological activation of SIRT3, a regulator of the mitochondrial oxidative stress response, has a protective effect on hearing thresholds after traumatic noise damage in mice. In contrast, the role of endogenously activated SIRT3 in hearing recovery has not been established. Here we tested the hypothesis that SIRT3 is required in mice for recovery of auditory thresholds after a noise exposure that confers a temporary threshold shift (TTS). SIRT3-specific immunoreactivity is present in outer hair cells, around the post-synaptic regions of inner hair cells, and faintly within inner hair cells. Prior to noise exposure, homozygous Sirt3-KO mice have slightly but significantly higher thresholds than their wild-type littermates measured by the auditory brainstem response (ABR), but not by distortion product otoacoustic emissions (DPOAE). Moreover, homozygous Sirt3-KO mice display a significant reduction in the progression of their peak 1 amplitude at higher frequencies prior to noise exposure. After exposure to a single sub-traumatic noise dose that does not permanently reduce cochlear function, compromise cell survival, or damage synaptic structures in wild-type mice, there was no difference in hearing function between the two genotypes, measured by ABR and DPOAE. The numbers of hair cells and auditory synapses were similar in both genotypes before and after noise exposure. These loss-of-function studies complement previously published gain-of-function studies and help refine our understanding of SIRT3’s role in cochlear homeostasis under different damage paradigms. They suggest that SIRT3 may promote spiral ganglion neuron function. They imply that cellular mechanisms of homeostasis, in addition to the mitochondrial oxidative stress response, act to restore hearing after TTS. Finally, we present a novel application of a biomedical statistical analysis for identifying changes between peak 1 amplitude progressions in ABR waveforms after damage.
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Affiliation(s)
- Sally Patel
- Department of Neuroscience, Ernest J. Del Monte Institute for Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Lisa Shah
- Department of Neuroscience, Ernest J. Del Monte Institute for Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Natalie Dang
- Department of Neuroscience, Ernest J. Del Monte Institute for Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Xiaodong Tan
- Department of Otolaryngology-Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Anthony Almudevar
- Department of Biostatistics and Computational Biology, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Patricia M. White
- Department of Neuroscience, Ernest J. Del Monte Institute for Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
- * E-mail:
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17
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Liu X, Li L, Chen GD, Salvi R. How low must you go? Effects of low-level noise on cochlear neural response. Hear Res 2020; 392:107980. [DOI: 10.1016/j.heares.2020.107980] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 04/17/2020] [Accepted: 04/21/2020] [Indexed: 10/24/2022]
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18
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Preventing presbycusis in mice with enhanced medial olivocochlear feedback. Proc Natl Acad Sci U S A 2020; 117:11811-11819. [PMID: 32393641 DOI: 10.1073/pnas.2000760117] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
"Growing old" is the most common cause of hearing loss. Age-related hearing loss (ARHL) (presbycusis) first affects the ability to understand speech in background noise, even when auditory thresholds in quiet are normal. It has been suggested that cochlear denervation ("synaptopathy") is an early contributor to age-related auditory decline. In the present work, we characterized age-related cochlear synaptic degeneration and hair cell loss in mice with enhanced α9α10 cholinergic nicotinic receptors gating kinetics ("gain of function" nAChRs). These mediate inhibitory olivocochlear feedback through the activation of associated calcium-gated potassium channels. Cochlear function was assessed via distortion product otoacoustic emissions and auditory brainstem responses. Cochlear structure was characterized in immunolabeled organ of Corti whole mounts using confocal microscopy to quantify hair cells, auditory neurons, presynaptic ribbons, and postsynaptic glutamate receptors. Aged wild-type mice had elevated acoustic thresholds and synaptic loss. Afferent synapses were lost from inner hair cells throughout the aged cochlea, together with some loss of outer hair cells. In contrast, cochlear structure and function were preserved in aged mice with gain-of-function nAChRs that provide enhanced olivocochlear inhibition, suggesting that efferent feedback is important for long-term maintenance of inner ear function. Our work provides evidence that olivocochlear-mediated resistance to presbycusis-ARHL occurs via the α9α10 nAChR complexes on outer hair cells. Thus, enhancement of the medial olivocochlear system could be a viable strategy to prevent age-related hearing loss.
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19
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Loss of inner hair cell ribbon synapses and auditory nerve fiber regression in Cldn14 knockout mice. Hear Res 2020; 391:107950. [PMID: 32251970 DOI: 10.1016/j.heares.2020.107950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 02/06/2020] [Accepted: 03/10/2020] [Indexed: 11/21/2022]
Abstract
Proper functioning of the auditory nerve is of critical importance for auditory rehabilitation by cochlear implants. Here we used the Cldn14-/- mouse to study in detail the effects of Claudin 14 loss on auditory synapses and the auditory nerve. Mutations in the tight junction protein Claudin 14 cause autosomal recessive non-syndromic hearing loss (DFNB29) in humans and mice, due to extensive degeneration of outer and inner hair cells. Here we show that massive inner hair cell loss in Cldn14-/- mice starts after the third postnatal week. Immunohistochemical analysis, using presynaptic Ribeye and postsynaptic GluR2 or PSD 95 as markers, revealed the degeneration of full ribbon synapses in inner hair cells from apical cochlear regions already at postnatal day 12 (P12). At P20, significant reduction in number of ribbon synapses has been observed for all cochlear regions and the loss of synaptic ribbons becomes even more prominent in residual inner hair cells from middle and apical cochlear regions at P45, which by then lost more than 40% of all ribbon synapses. In contrast to excessive noise exposure, loss of Claudin 14 does not cause an increase in "orphan" ribbons with no postsynaptic counterpart due to a reduction of postsynaptic structures. Hair cell loss in Cldn14-/- mice is associated with regression of peripheral auditory nerve processes, especially of outer radial fibers, which normally innervate the outer hair cells. The number of spiral ganglion neurons per area, however, was unchanged between the genotypes. Different effects were observed in the cochlear nucleus complex (CNC), the central projection area of the auditory nerve. While the dorsal cochlear nucleus (DCN) showed a significant 19.7% volume reduction, VGLUT-1 input was reduced by 34.4% in the ventral cochlear nucleus (VCN) but not in the DCN of Cldn14-/- mice. Taken together, massive inner hair cell loss starts after the third postnatal week in Cldn14-/- mice, but is preceded by the loss of ribbon synapses, which may be a first sign of an ongoing degeneration process in otherwise morphologically inconspicuously inner hair cells. In addition to the regression of peripheral nerve processes, reduced levels of VGLUT-1 in the VCN of Cldn14-/- mice suggests that Claudin 14 loss does not only cause hair cell loss but also affects peripheral and central connectivity of the auditory nerve.
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20
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Reijntjes DOJ, Köppl C, Pyott SJ. Volume gradients in inner hair cell-auditory nerve fiber pre- and postsynaptic proteins differ across mouse strains. Hear Res 2020; 390:107933. [PMID: 32203820 DOI: 10.1016/j.heares.2020.107933] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 02/12/2020] [Accepted: 02/26/2020] [Indexed: 02/04/2023]
Abstract
In different animal models, auditory nerve fibers display variation in spontaneous activity and response threshold. Functional and structural differences among inner hair cell ribbon synapses are believed to contribute to this variation. The relative volumes of synaptic proteins at individual synapses might be one such difference. This idea is based on the observation of opposing volume gradients of the presynaptic ribbons and associated postsynaptic glutamate receptor patches in mice along the pillar modiolar axis of the inner hair cell, the same axis along which fibers were shown to vary in their physiological properties. However, it is unclear whether these opposing gradients are expressed consistently across animal models. In addition, such volume gradients observed for separate populations of presynaptic ribbons and postsynaptic glutamate receptor patches suggest different relative volumes of these synaptic structures at individual synapses; however, these differences have not been examined in mice. Furthermore, it is unclear whether such gradients are limited to these synaptic proteins. Therefore, we analyzed organs of Corti isolated from CBA/CaJ, C57BL/6, and FVB/NJ mice using immunofluorescence, confocal microscopy, and quantitative image analysis. We find consistent expression of presynaptic volume gradients across strains of mice and inconsistent expression of postsynaptic volume gradients. We find differences in the relative volume of synaptic proteins, but these are different between CBA/CaJ mice, and C57BL/6 and FVB/NJ mice. We find similar results in C57BL/6 and FVB/NJ mice when using other postsynaptic density proteins (Shank1, Homer, and PSD95). These results have implications for the mechanisms by which volumes of synaptic proteins contribute to variations in the physiology of individual auditory nerve fibers and their vulnerability to excitotoxicity.
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Affiliation(s)
- Daniël O J Reijntjes
- University of Groningen, University Medical Center Groningen, Groningen, Department of Otorhinolaryngology and Head/Neck Surgery, 9713 GZ, Groningen, the Netherlands.
| | - Christine Köppl
- Cluster of Excellence "Hearing4all" and Research Centre Neurosensory Science, Department of Neuroscience, School of Medicine and Health Science, Carl von Ossietzky University Oldenburg, Germany
| | - Sonja J Pyott
- University of Groningen, University Medical Center Groningen, Groningen, Department of Otorhinolaryngology and Head/Neck Surgery, 9713 GZ, Groningen, the Netherlands
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Amanipour RM, Zhu X, Duvey G, Celanire S, Walton JP, Frisina RD. Noise-Induced Hearing Loss in Mice: Effects of High and Low Levels of Noise Trauma in CBA Mice. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2018; 2018:1210-1213. [PMID: 30440607 DOI: 10.1109/embc.2018.8512525] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Acoustic trauma can induce temporary or permanent noise-induced hearing loss (NIHL). Noise exposed animal models allow us to study the effects of various noise trauma insults on the cochlea and auditory pathways. Here we studied the short-term and long-term functional changes occurring in the auditory system following exposure to two different noise traumas. Several measures of hearing function known to change following noise exposure were examined: Temporary (TTS) and permanent (PTS) threshold shifts were measured using auditory brainstem responses (ABR), outer hair cell function was examined using distortion product otoacoustic emissions (DPOAEs), and auditory temporal processing was assessed using a gap-in-noise (GIN) ABR paradigm. Physiological measures were made before and after the exposure (24 hours, 2 weeks, 4 weeks, and 1 year). The animals were perfused and their brain, and cochlea were collected for future biomarker studies. Young adult mice were exposed to 110 dB and 116 dB octave-band noise levels for 45 minutes, and both groups demonstrated significant threshold shifts 1 day post-noise exposure across all frequencies. However 2 weeks postexposure, PTS within the 110 dB group was significantly reduced compared to 1 day post trauma, this improvement in thresholds was not as great in the 116 dB exposure group. At 2 weeks post-trauma, differences between the measured PTS in the two groups was significant for 4 of the 7 measured frequencies. At this 1 year time point after exposure, mice in the 110 dB group showed very minor PTS, but the 116 dB group showed a large PTS comparable to their 2 and 4 week PTS. At this time point, PTS variation between the two groups was significant across all frequencies. DPOAE amplitudes measured 2 weeks post exposure showed recovery for all frequencies within 10 dB (average) of the baseline in the 110 dB group, however for the 116 dB exposure DP amplitudes were elevated by about 30 dB. The differences in DPOAE amplitudes between the 110 dB and 116 dB groups were significant at 2 weeks, 4 weeks, and 1 year post-trauma in the mid frequency range. At 2 weeks, 4 weeks, and 1 year, DPOAE thresholds returned to within 10 dB of the baseline for the 110 dB group in the low and mid frequency range, whereas the 116 dB group still showed shifts of 30 dB for all frequency ranges. For Gap ABRs, there was a significant decrease in both noise burst 1 (NB1) and noise burst 2 (NB2) amplitudes for peaks 1 and 4 in the 116 dB group relative to the 110 dB group when measured at 1 year post trauma. These results indicate that a 6 dB increase in noise exposure intensity results in a significant increased ototrauma in both the peripheral and central auditory systems.
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Sheppard A, Liu X, Ding D, Salvi R. Auditory central gain compensates for changes in cochlear output after prolonged low-level noise exposure. Neurosci Lett 2018; 687:183-188. [PMID: 30273699 DOI: 10.1016/j.neulet.2018.09.054] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 09/13/2018] [Accepted: 09/27/2018] [Indexed: 01/11/2023]
Abstract
Remarkably, the central auditory system can modify the strength of its sound-evoked neural response based on prior acoustic experiences, a phenomenon referred to as central gain. Gain changes are well documented following traumatic noise exposure, but much less is known about central gain dynamics following prolonged exposure to low-level noise, a common acoustic experience in many urban and work environments. We recently reported that the neural output of the cochlea is reduced, while gain was enhanced in the inferior colliculus (IC) following a 5-week exposure to 75 dB noise. To determine if similar effects were present at even lower intensities, we exposed rats to a 65 dB noise expecting to see little to no change in the cochlea or IC. The exposure had little effect on distortion product otoacoustic emissions and did not cause any hair cell loss. However, the amplitude of the CAP, which reflects the neural output of cochlea, was depressed by 50-75%. Surprisingly, neural responses from the IC were enhanced up to 70%, mainly at frequencies within the noise exposure band. One-week post-exposure, CAP amplitudes returned to normal at frequencies within or above the exposure band, whereas responses evoked by frequencies below the exposure band were enhanced by more than 80%. In contrast, IC responses below the exposure frequency were depressed 10-20% whereas responses within the exposure frequency band were enhanced 10-20%. Thus, the central auditory system dynamically up- and down-regulates its gain to maintain supra-threshold neural responses within a narrow homeostatic range; a function that likely contributes to the prevention of sounds from being perceived as muffled or too loud.
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Affiliation(s)
- Adam Sheppard
- Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA.
| | - Xiaopeng Liu
- Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Dalian Ding
- Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Richard Salvi
- Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA; Department of Speech Pathology and Audiology, Asia University, Taiwan
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23
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Kindt KS, Sheets L. Transmission Disrupted: Modeling Auditory Synaptopathy in Zebrafish. Front Cell Dev Biol 2018; 6:114. [PMID: 30258843 PMCID: PMC6143809 DOI: 10.3389/fcell.2018.00114] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/23/2018] [Indexed: 01/04/2023] Open
Abstract
Sensorineural hearing loss is the most common form of hearing loss in humans, and results from either dysfunction in hair cells, the sensory receptors of sound, or the neurons that innervate hair cells. A specific type of sensorineural hearing loss, referred to as auditory synaptopathy, occurs when hair cells are able to detect sound but fail to transmit sound stimuli at the hair-cell synapse. Auditory synaptopathy can originate from genetic alterations that specifically disrupt hair-cell synapse function. Additionally, environmental factors such as noise exposure can leave hair cells intact but result in loss of hair-cell synapses, and represent an acquired form of auditory synaptopathy. The zebrafish model has emerged as a valuable system for studies of hair-cell function, and specifically hair-cell synaptopathy. In this review, we describe the experimental tools that have been developed to study hair-cell synapses in zebrafish. We discuss how zebrafish genetics has helped identify and define the roles of hair-cell synaptic proteins crucial for hearing in humans, and highlight how studies in zebrafish have contributed to our understanding of hair-cell synapse formation and function. In addition, we also discuss work that has used noise exposure or pharmacological mimic of noise-induced excitotoxicity in zebrafish to define cellular mechanisms underlying noise-induced hair-cell damage and synapse loss. Lastly, we highlight how future studies in zebrafish could enhance our understanding of the pathological processes underlying synapse loss in both genetic and acquired auditory synaptopathy. This knowledge is critical in order to develop therapies that protect or repair auditory synaptic contacts.
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Affiliation(s)
- Katie S. Kindt
- Section on Sensory Cell Development and Function, NIDCD/National Institutes of Health, Bethesda, MD, United States
| | - Lavinia Sheets
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO, United States
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24
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Barbee CM, James JA, Park JH, Smith EM, Johnson CE, Clifton S, Danhauer JL. Effectiveness of Auditory Measures for Detecting Hidden Hearing Loss and/or Cochlear Synaptopathy: A Systematic Review. Semin Hear 2018; 39:172-209. [PMID: 29915454 DOI: 10.1055/s-0038-1641743] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Standard audiometric evaluations are not sensitive enough to identify hidden hearing loss (HHL) and/or cochlear synaptopathy (CS). Patients with either of these conditions frequently present with difficulty understanding speech in noise or other complaints such as tinnitus. The purpose of this systematic review is to identify articles in peer-reviewed journals that assessed the sensitivity of audiologic measures for detecting HHL and/or CS, and which showed potential for use in a clinical test battery for these disorders. A reference librarian submitted specific boolean terminology to MEDLINE, Embase, and Web of Science. The authors used a consensus approach with specially designed score sheets for the selection of titles, abstracts, and then articles for inclusion in the systematic review and for quality assessment. Fifteen articles were included in the systematic review. Seven articles involved humans; seven involved animals, and one study used both humans and animals. Results showed that pure-tone audiometry to 20 kHz, otoacoustic emissions, electrocochleography, auditory brainstem response (ABR), electrophysiological tests, speech recognition in noise with and without temporal distortion, interviews, and self-report measures have been used to assess HHL and/or CS. For HHL, ultra-high-frequency audiometry may help identify persons with sensory hair cell loss that does not show up on standard audiograms. Promising nonbehavioral measures for CS included ABR wave I amplitude, the summating potential-to-action potential ratio, and speech recognition in noise with and without temporal distortion. Self-report questionnaires also may help identify auditory dysfunction in persons with normal hearing.
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Affiliation(s)
- Christi M Barbee
- Hearing Evaluation, Rehabilitation, and Outcomes Laboratory, Department of Communication Sciences and Disorders, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Jessica A James
- Hearing Evaluation, Rehabilitation, and Outcomes Laboratory, Department of Communication Sciences and Disorders, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Jin Hyung Park
- Hearing Evaluation, Rehabilitation, and Outcomes Laboratory, Department of Communication Sciences and Disorders, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Emily M Smith
- Hearing Evaluation, Rehabilitation, and Outcomes Laboratory, Department of Communication Sciences and Disorders, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Carole E Johnson
- Hearing Evaluation, Rehabilitation, and Outcomes Laboratory, Department of Communication Sciences and Disorders, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Shari Clifton
- Hearing Evaluation, Rehabilitation, and Outcomes Laboratory, Department of Communication Sciences and Disorders, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Jeffrey L Danhauer
- Department of Speech and Hearing Sciences, University of California Santa Barbara, Santa Barbara, California
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25
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Eggermont JJ. Effects of long-term non-traumatic noise exposure on the adult central auditory system. Hearing problems without hearing loss. Hear Res 2017; 352:12-22. [DOI: 10.1016/j.heares.2016.10.015] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 10/18/2016] [Accepted: 10/21/2016] [Indexed: 11/27/2022]
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26
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Severe hearing loss and outer hair cell death in homozygous Foxo3 knockout mice after moderate noise exposure. Sci Rep 2017; 7:1054. [PMID: 28432353 PMCID: PMC5430619 DOI: 10.1038/s41598-017-01142-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 03/22/2017] [Indexed: 12/22/2022] Open
Abstract
Noise induced hearing loss (NIHL) is a disease that affects millions of Americans. Identifying genetic pathways that influence recovery from noise exposure is an important step forward in understanding NIHL. The transcription factor Foxo3 integrates the cellular response to oxidative stress and plays a role in extending lifespan in many organisms, including humans. Here we show that Foxo3 is required for auditory function after noise exposure in a mouse model system, measured by ABR. Absent Foxo3, outer hair cells are lost throughout the middle and higher frequencies. SEM reveals persistent damage to some surviving outer hair cell stereocilia. However, DPOAE analysis reveals that some function is preserved in low frequency outer hair cells, despite concomitant profound hearing loss. Inner hair cells, auditory synapses and spiral ganglion neurons are all present after noise exposure in the Foxo3KO/KO fourteen days post noise (DPN). We also report anti-Foxo3 immunofluorescence in adult human outer hair cells. Taken together, these data implicate Foxo3 and its transcriptional targets in outer hair cell survival after noise damage. An additional role for Foxo3 in preserving hearing is likely, as low frequency auditory function is absent in noise exposed Foxo3KO/KOs even though all cells and structures are present.
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27
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Hickox AE, Larsen E, Heinz MG, Shinobu L, Whitton JP. Translational issues in cochlear synaptopathy. Hear Res 2017; 349:164-171. [PMID: 28069376 DOI: 10.1016/j.heares.2016.12.010] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 12/15/2016] [Accepted: 12/16/2016] [Indexed: 10/20/2022]
Abstract
Understanding the biology of the previously underappreciated sensitivity of cochlear synapses to noise insult, and its clinical consequences, is becoming a mission for a growing number of auditory researchers. In addition, several research groups have become interested in developing therapeutic approaches that can reverse synaptopathy and restore hearing function. One of the major challenges to realizing the potential of synaptopathy rodent models is that current clinical audiometric approaches cannot yet reveal the presence of this subtle cochlear pathology in humans. This has catalyzed efforts, both from basic and clinical perspectives, to investigate novel means for diagnosing synaptopathy and to determine the main functional consequences for auditory perception and hearing abilities. Such means, and a strong concordance between findings in pre-clinical animal models and clinical studies in humans, are important for developing and realizing therapeutics. This paper frames the key outstanding translational questions that need to be addressed to realize this ambitious goal.
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Affiliation(s)
- Ann E Hickox
- Decibel Therapeutics, 215 First St, Cambridge, MA, 02142, USA.
| | - Erik Larsen
- Decibel Therapeutics, 215 First St, Cambridge, MA, 02142, USA.
| | - Michael G Heinz
- Speech, Language, and Hearing Sciences and Biomedical Engineering, Purdue University, 715 Clinic Drive, West Lafayette, IN, 47907, USA.
| | - Leslie Shinobu
- Decibel Therapeutics, 215 First St, Cambridge, MA, 02142, USA.
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28
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Ohlemiller KK, Jones SM, Johnson KR. Application of Mouse Models to Research in Hearing and Balance. J Assoc Res Otolaryngol 2016; 17:493-523. [PMID: 27752925 PMCID: PMC5112220 DOI: 10.1007/s10162-016-0589-1] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 09/15/2016] [Indexed: 01/10/2023] Open
Abstract
Laboratory mice (Mus musculus) have become the major model species for inner ear research. The major uses of mice include gene discovery, characterization, and confirmation. Every application of mice is founded on assumptions about what mice represent and how the information gained may be generalized. A host of successes support the continued use of mice to understand hearing and balance. Depending on the research question, however, some mouse models and research designs will be more appropriate than others. Here, we recount some of the history and successes of the use of mice in hearing and vestibular studies and offer guidelines to those considering how to apply mouse models.
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Affiliation(s)
- Kevin K Ohlemiller
- Department of Otolaryngology, Central Institute for the Deaf, Fay and Carl Simons Center for Hearing and Deafness, Washington University School of Medicine, 660 S. Euclid, Saint Louis, MO, 63110, USA.
| | - Sherri M Jones
- Department of Special Education and Communication Disorders, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
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