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Foster T, Lim P, Jones M, Wagle SR, Kovacevic B, Ionescu CM, Wong EYM, Mooranian A, Al-Salami H. Polymer-Based Nanoparticles for Inner Ear Targeted Trans Differentiation Gene Therapy. ChemMedChem 2024:e202400038. [PMID: 38818625 DOI: 10.1002/cmdc.202400038] [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: 01/11/2024] [Revised: 05/27/2024] [Accepted: 05/27/2024] [Indexed: 06/01/2024]
Abstract
Hearing loss is a significant disability that often goes under recognised, largely due to poor identification, prevention, and treatment. Steps are being made to amend these pitfalls in the investigation of hearing loss, however, the development of a cure to reverse advanced forms remains distant. This review details some current advances in the treatment of hearing loss, with a particular focus on genetic-based nanotechnology and how it may provide a useful avenue for further research. This review presents a broad background on the pathophysiology of hearing loss and some current interventions. We also highlight some potential genes that may be useful in the amelioration of hearing loss. Pathways of cellular differentiation from stem or supporting cell to functional hair cell are covered in detail, as this mechanism represents a key means of regenerating these cell types. Overall, we believe that polymer-based nanotechnology coupled with novel excipients represents a useful area of further research in the treatment of hearing loss, although further studies in this area are required.
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Affiliation(s)
- Thomas Foster
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, 6102, Western Australia, Australia
- Department of Clinical Biochemistry, Pathwest Laboratory Medicine, Royal Perth Hospital, Perth, 6000, Western Australia, Australia
| | - Patrick Lim
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, 6102, Western Australia, Australia
| | - Melissa Jones
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, 6102, Western Australia, Australia
- Hearing Therapeutics Department, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands 6009, Perth, Western Australia, Australia
| | - Susbin Raj Wagle
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, 6102, Western Australia, Australia
| | - Bozica Kovacevic
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, 6102, Western Australia, Australia
| | - Corina Mihaela Ionescu
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, 6102, Western Australia, Australia
| | - Elaine Y M Wong
- Hearing Therapeutics Department, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands 6009, Perth, Western Australia, Australia
| | - Armin Mooranian
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, 6102, Western Australia, Australia
- School of Pharmacy, University of Otago, Dunedin 9016, Otago, New Zealand
| | - Hani Al-Salami
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley, 6102, Western Australia, Australia
- Medical School, The University of Western Australia, Crawley, 6009, Western Australia, Australia
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Schaefer S, Sladen M, Nichani J, Millward K, Lockley M, O'Driscoll M, Kluk K, Bruce IA. Hearing preservation in paediatric cochlear implantation with the Nucleus Slim Straight Electrode - our experience. Int J Audiol 2024:1-8. [PMID: 38319187 DOI: 10.1080/14992027.2024.2306191] [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: 09/20/2021] [Accepted: 01/11/2024] [Indexed: 02/07/2024]
Abstract
OBJECTIVE to evaluate the levels of successful hearing preservation and preservation of functional hearing following cochlear implantation (HPCI) in children using the Cochlear Nucleus® Slim Straight Electrode (SSE). DESIGN retrospective case note review of paediatric HPCI cases in our CI centre from 2013 to 2023. Inclusion criteria were attempted hearing preservation surgery, SSE used for implantation, pre-operative hearing thresholds ≤80dBHL at 250 Hz, CI before 18 years of age. Patients were excluded if no postoperative unaided PTA was obtained (poor attendance). Primairy outcome was hearing preservation using the HEARRING group formula; secondary outcome was residual functional hearing (≤80dBHL at 250 Hz/<90dB LFPTA). STUDY SAMPLE 56 patients with 94 CI's were included for review. RESULTS Hearing preservation was achieved in 94.7% (89/94) of ears and complete preservation in 72% (68/94)). Average functional hearing was preserved in 89% using both criteria for preservation. Long-term follow up data was available for 36 ears (average 35.2 months), demonstrating 88.9% (32/36) complete preservation. CONCLUSION We have reliably achieved and maintained a high success rate of HPCI using the SSE in our paediatric population. The field of HPCI would benefit from unification of outcome reporting in order to optimise the evidence available to professionals, patients and their carers.
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Affiliation(s)
- Simone Schaefer
- Department of Paediatric Otolaryngology, Royal Manchester Children's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Mark Sladen
- Richard Ramsden Centre for Auditory Implants, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Jaya Nichani
- Department of Paediatric Otolaryngology, Royal Manchester Children's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Kerri Millward
- Richard Ramsden Centre for Auditory Implants, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Morag Lockley
- Richard Ramsden Centre for Auditory Implants, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Martin O'Driscoll
- Richard Ramsden Centre for Auditory Implants, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Karolina Kluk
- Manchester Centre for Audiology and Deafness (ManCAD), Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Iain A Bruce
- Department of Paediatric Otolaryngology, Royal Manchester Children's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
- Division of Infection, Immunity and Respiratory Medicine, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
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3
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Plontke SK, Girndt M, Meisner C, Fischer I, Böselt I, Löhler J, Ludwig-Kraus B, Richter M, Steighardt J, Reuter B, Böttcher C, Langer J, Pethe W, Seiwerth I, Jovanovic N, Großmann W, Kienle-Gogolok A, Boehm A, Neudert M, Diensthuber M, Müller A, Dazert S, Guntinas-Lichius O, Hornung J, Vielsmeier V, Stadler J, Rahne T. High-Dose Glucocorticoids for the Treatment of Sudden Hearing Loss. NEJM EVIDENCE 2024; 3:EVIDoa2300172. [PMID: 38320514 DOI: 10.1056/evidoa2300172] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
BACKGROUND: Systemic glucocorticoids are commonly used for primary therapy of idiopathic sudden sensorineural hearing loss (ISSNHL). However, the comparative effectiveness and risk profiles of high-dose over lower-dose regimens remain unknown. METHODS: We randomly assigned patients with sudden hearing loss of greater than or equal to 50 dB within 7 days from onset to receive either 5 days of high-dose intravenous prednisolone at 250 mg/d (HD-Pred), 5 days of high-dose oral dexamethasone at 40 mg/d (HD-Dex), or, as a control, 5 days of oral prednisolone (Pred-Control) at 60 mg/d followed by 5 days of tapering doses. The primary outcome was the change in hearing threshold (pure tone average) in the three most affected contiguous frequencies from baseline to day 30. Secondary outcomes included speech understanding, tinnitus, communication competence, quality of life, hypertension, and insulin resistance. RESULTS: A total of 325 patients were randomly assigned. Mean change in 3PTAmost affected hearing threshold from baseline to 30 days was 34.2 dB (95% CI, 28.4 to 40.0) in the HD-Pred group, 41.4 dB (95% CI, 35.6 to 47.2) in the HD-Dex group, and 41.0 dB (95% CI, 35.2 to 46.8) in the Pred-Control group (P=0.09 for analysis of variance). There were more adverse events related to trial medication in the HD-Pred (n=73) and HD-Dex (n=76) groups than in the Pred-Control group (n=46). CONCLUSIONS: Systemic high-dose glucocorticoid therapy was not superior to a lower-dose regimen in patients with ISSNHL, and it was associated with a higher risk of side effects. (Funded by the Federal Ministry of Education and Research [BMBF]; EudraCT number, 2015‐002602‐36.)
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Affiliation(s)
- Stefan K Plontke
- Department of Otorhinolaryngology, Head & Neck Surgery, University Medicine Halle, Halle (Saale), Germany
| | - Matthias Girndt
- Department of Internal Medicine, University Medicine Halle, Halle (Saale), Germany
| | - Christoph Meisner
- Robert Bosch Society for Medical Research, Robert Bosch Hospital, Stuttgart, Germany
| | - Imma Fischer
- Institute for Clinical Epidemiology and Applied Biometry, University of Tübingen, Tübingen, Germany
| | - Iris Böselt
- Coordination Centre for Clinical Trials, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Jan Löhler
- Scientific Institute for Applied Oto-Rhino-Laryngology of the German Professional Association of ENT Surgeons, Bad Bramstedt, Germany
| | - Beatrice Ludwig-Kraus
- Department of Laboratory Medicine, Central Laboratory, University Hospital Halle, Halle (Saale), Germany
| | - Michael Richter
- Coordination Centre for Clinical Trials, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Jörg Steighardt
- Coordination Centre for Clinical Trials, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Bernd Reuter
- Department of Otorhinolaryngology/Plastic Surgery, SRH Zentralklinikum Suhl, Suhl, Germany
| | - Christoph Böttcher
- Department of Otorhinolaryngology/Plastic Surgery, SRH Zentralklinikum Suhl, Suhl, Germany
- ENT Practice, Bad Neustadt, Germany
| | - Jörg Langer
- ENT Department, AMEOS Clinic Halberstadt, Halberstadt, Germany
| | - Wolfram Pethe
- ENT Department, AMEOS Clinic Halberstadt, Halberstadt, Germany
| | - Ingmar Seiwerth
- Department of Otorhinolaryngology, Head & Neck Surgery, University Medicine Halle, Halle (Saale), Germany
| | - Nebojsa Jovanovic
- Department of Otorhinolaryngology, Head and Neck Surgery, Plastic Surgery, University Hospital of Giessen and Marburg, Giessen, Germany
| | - Wilma Großmann
- Department of Otorhinolaryngology, Head and Neck Surgery "Otto Körner," Rostock University Medical Center, Rostock, Germany
| | | | - Andreas Boehm
- ENT Department, Hospital St. Georg gGmbH, Leipzig, Germany
| | - Marcus Neudert
- Department of Otorhinolaryngology, Head and Neck Surgery, Technical University Dresden, Faculty of Medicine and University Hospital Carl Gustav Carus, Dresden, Germany
| | - Marc Diensthuber
- Department of Otorhinolaryngology, Goethe University Frankfurt, University Hospital, Frankfurt, Germany
| | - Andreas Müller
- Department Otorhinolaryngology/Plastic Surgery, SRH Wald-Klinikum Gera gGmbH, Gera, Germany
| | - Stefan Dazert
- Department of Otorhinolaryngology, Head and Neck Surgery, St. Elisabeth Hospital, Ruhr University Bochum, Bochum, Germany
| | | | - Joachim Hornung
- Department of Otorhinolaryngology and Head and Neck Surgery, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Veronika Vielsmeier
- Department of Otorhinolaryngology, University of Regensburg, Regensburg, Germany
| | - Joachim Stadler
- Department of Otorhinolaryngology, Head and Neck Surgery, Heinrich-Braun-Klinikum gGmbH, Zwickau, Germany
| | - Torsten Rahne
- Department of Otorhinolaryngology, Head & Neck Surgery, University Medicine Halle, Halle (Saale), Germany
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Manohar S, Chen GD, Li L, Liu X, Salvi R. Chronic stress induced loudness hyperacusis, sound avoidance and auditory cortex hyperactivity. Hear Res 2023; 431:108726. [PMID: 36905854 DOI: 10.1016/j.heares.2023.108726] [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: 10/03/2022] [Revised: 02/22/2023] [Accepted: 02/28/2023] [Indexed: 03/06/2023]
Abstract
Hyperacusis, a debilitating loudness intolerance disorder, has been linked to chronic stress and adrenal insufficiency. To investigate the role of chronic stress, rats were chronically treated with corticosterone (CORT) stress hormone. Chronic CORT produced behavioral evidence of loudness hyperacusis, sound avoidance hyperacusis, and abnormal temporal integration of loudness. CORT treatment did not disrupt cochlear or brainstem function as reflected by normal distortion product otoacoustic emissions, compound action potentials, acoustic startle reflexex, and auditory brainstem responses. In contrast, the evoked response from the auditory cortex was enhanced up to three fold after CORT treatment. This hyperactivity was associated with a significant increase in glucocorticoid receptors in auditory cortex layers II/III and VI. Basal serum CORT levels remained normal after chronic CORT stress whereas reactive serum CORT levels evoked by acute restraint stress were blunted (reduced) after chronic CORT stress; similar changes were observed after chronic, intense noise stress. Taken together, our results show for the first time that chronic stress can induce hyperacusis and sound avoidance. A model is proposed in which chronic stress creates a subclinical state of adrenal insufficiency that establishes the necessary conditions for inducing hyperacusis.
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Affiliation(s)
- Senthilvelan Manohar
- Center for Hearing and Deafness, 137 Cary Hall, University at Buffalo, Buffalo, NY 14214, USA
| | - Guang-Di Chen
- Center for Hearing and Deafness, 137 Cary Hall, University at Buffalo, Buffalo, NY 14214, USA
| | - Li Li
- Center for Hearing and Deafness, 137 Cary Hall, University at Buffalo, Buffalo, NY 14214, USA
| | - Xiaopeng Liu
- Center for Hearing and Deafness, 137 Cary Hall, University at Buffalo, Buffalo, NY 14214, USA
| | - Richard Salvi
- Center for Hearing and Deafness, 137 Cary Hall, University at Buffalo, Buffalo, NY 14214, USA.
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Calis D, Hess M, Marchetta P, Singer W, Modro J, Nelissen E, Prickaerts J, Sandner P, Lukowski R, Ruth P, Knipper M, Rüttiger L. Acute deletion of the central MR/GR steroid receptor correlates with changes in LTP, auditory neural gain, and GC-A cGMP signaling. Front Mol Neurosci 2023; 16:1017761. [PMID: 36873102 PMCID: PMC9983609 DOI: 10.3389/fnmol.2023.1017761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 01/18/2023] [Indexed: 02/19/2023] Open
Abstract
The complex mechanism by which stress can affect sensory processes such as hearing is still poorly understood. In a previous study, the mineralocorticoid (MR) and/or glucocorticoid receptor (GR) were deleted in frontal brain regions but not cochlear regions using a CaMKIIα-based tamoxifen-inducible Cre ERT2/loxP approach. These mice exhibit either a diminished (MRTMXcKO) or disinhibited (GRTMXcKO) auditory nerve activity. In the present study, we observed that mice differentially were (MRTMXcKO) or were not (GRTMXcKO) able to compensate for altered auditory nerve activity in the central auditory pathway. As previous findings demonstrated a link between central auditory compensation and memory-dependent adaptation processes, we analyzed hippocampal paired-pulse facilitation (PPF) and long-term potentiation (LTP). To determine which molecular mechanisms may impact differences in synaptic plasticity, we analyzed Arc/Arg3.1, known to control AMPA receptor trafficking, as well as regulators of tissue perfusion and energy consumption (NO-GC and GC-A). We observed that the changes in PPF of MRTMXcKOs mirrored the changes in their auditory nerve activity, whereas changes in the LTP of MRTMXcKOs and GRTMXcKOs mirrored instead the changes in their central compensation capacity. Enhanced GR expression levels in MRTMXcKOs suggest that MRs typically suppress GR expression. We observed that hippocampal LTP, GC-A mRNA expression levels, and ABR wave IV/I ratio were all enhanced in animals with elevated GR (MRTMXcKOs) but were all lower or not mobilized in animals with impaired GR expression levels (GRTMXcKOs and MRGRTMXcKOs). This suggests that GC-A may link LTP and auditory neural gain through GR-dependent processes. In addition, enhanced NO-GC expression levels in MR, GR, and MRGRTMXcKOs suggest that both receptors suppress NO-GC; on the other hand, elevated Arc/Arg3.1 levels in MRTMXcKOs and MRGRTMXcKOs but not GRTMXcKOs suggest that MR suppresses Arc/Arg3.1 expression levels. Conclusively, MR through GR inhibition may define the threshold for hemodynamic responses for LTP and auditory neural gain associated with GC-A.
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Affiliation(s)
- Dila Calis
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Morgan Hess
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Philine Marchetta
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Wibke Singer
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Julian Modro
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Ellis Nelissen
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, Netherlands
| | - Jos Prickaerts
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, Netherlands
| | - Peter Sandner
- Bayer Health Care Pharmaceuticals, Global Drug Discovery Pharma Research Centre Wuppertal, Wuppertal, Germany
| | - Robert Lukowski
- Institute of Pharmacy, Pharmacology, Toxicology and Clinical Pharmacy, University of Tübingen, Tübingen, Germany
| | - Peter Ruth
- Institute of Pharmacy, Pharmacology, Toxicology and Clinical Pharmacy, University of Tübingen, Tübingen, Germany
| | - Marlies Knipper
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Lukas Rüttiger
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
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Barrallo-Gimeno A, Llorens J. Hair cell toxicology: With the help of a little fish. Front Cell Dev Biol 2022; 10:1085225. [PMID: 36582469 PMCID: PMC9793777 DOI: 10.3389/fcell.2022.1085225] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 11/28/2022] [Indexed: 12/15/2022] Open
Abstract
Hearing or balance loss are disabling conditions that have a serious impact in those suffering them, especially when they appear in children. Their ultimate cause is frequently the loss of function of mechanosensory hair cells in the inner ear. Hair cells can be damaged by environmental insults, like noise or chemical agents, known as ototoxins. Two of the most common ototoxins are life-saving medications: cisplatin against solid tumors, and aminoglycoside antibiotics to treat infections. However, due to their localization inside the temporal bone, hair cells are difficult to study in mammals. As an alternative animal model, zebrafish larvae have hair cells similar to those in mammals, some of which are located in a fish specific organ on the surface of the skin, the lateral line. This makes them easy to observe in vivo and readily accessible for ototoxins or otoprotective substances. These features have made possible advances in the study of the mechanisms mediating ototoxicity or identifying new potential ototoxins. Most importantly, the small size of the zebrafish larvae has allowed screening thousands of molecules searching for otoprotective agents in a scale that would be highly impractical in rodent models. The positive hits found can then start the long road to reach clinical settings to prevent hearing or balance loss.
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Affiliation(s)
- Alejandro Barrallo-Gimeno
- Department de Ciències Fisiològiques, Facultat de Medicina i Ciències de la Salut, Campus de Bellvitge, Universitat de Barcelona, L’Hospitalet de Llobregat, Spain,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain,Institut D'Investigació Biomèdica de Bellvitge, IDIBELL, L’Hospitalet de Llobregat, Spain,*Correspondence: Alejandro Barrallo-Gimeno,
| | - Jordi Llorens
- Department de Ciències Fisiològiques, Facultat de Medicina i Ciències de la Salut, Campus de Bellvitge, Universitat de Barcelona, L’Hospitalet de Llobregat, Spain,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain,Institut D'Investigació Biomèdica de Bellvitge, IDIBELL, L’Hospitalet de Llobregat, Spain
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Savitska D, Hess M, Calis D, Marchetta P, Harasztosi C, Fink S, Eckert P, Ruth P, Rüttiger L, Knipper M, Singer W. Stress Affects Central Compensation of Neural Responses to Cochlear Synaptopathy in a cGMP-Dependent Way. Front Neurosci 2022; 16:864706. [PMID: 35968392 PMCID: PMC9372611 DOI: 10.3389/fnins.2022.864706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 06/16/2022] [Indexed: 11/13/2022] Open
Abstract
In light of the increasing evidence supporting a link between hearing loss and dementia, it is critical to gain a better understanding of the nature of this relationship. We have previously observed that following cochlear synaptopathy, the temporal auditory processing (e.g., auditory steady state responses, ASSRs), is sustained when reduced auditory input is centrally compensated. This central compensation process was linked to elevated hippocampal long-term potentiation (LTP). We further observed that, independently of age, central responsiveness to cochlear synaptopathy can differ, resulting in either a low or high capacity to compensate for the reduced auditory input. Lower central compensation resulted in poorer temporal auditory processing, reduced hippocampal LTP, and decreased recruitment of activity-dependent brain-derived neurotrophic factor (BDNF) expression in hippocampal regions (low compensators). Higher central compensation capacity resulted in better temporal auditory processing, higher LTP responses, and increased activity-dependent BDNF expression in hippocampal regions. Here, we aimed to identify modifying factors that are potentially responsible for these different central responses. Strikingly, a poorer central compensation capacity was linked to lower corticosterone levels in comparison to those of high compensators. High compensators responded to repeated placebo injections with elevated blood corticosterone levels, reduced auditory brainstem response (ABR) wave I amplitude, reduced inner hair cell (IHC) ribbon number, diminished temporal processing, reduced LTP responses, and decreased activity-dependent hippocampal BDNF expression. In contrast, the same stress exposure through injection did not elevate blood corticosterone levels in low compensators, nor did it reduce IHC ribbons, ABR wave I amplitude, ASSR, LTP, or BDNF expression as seen in high compensators. Interestingly, in high compensators, the stress-induced responses, such as a decline in ABR wave I amplitude, ASSR, LTP, and BDNF could be restored through the “memory-enhancing” drug phosphodiesterase 9A inhibitor (PDE9i). In contrast, the same treatment did not improve these aspects in low compensators. Thus, central compensation of age-dependent cochlear synaptopathy is a glucocorticoid and cyclic guanosine-monophosphate (cGMP)-dependent neuronal mechanism that fails upon a blunted stress response.
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Affiliation(s)
- Daria Savitska
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Morgan Hess
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Dila Calis
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Philine Marchetta
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Csaba Harasztosi
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Stefan Fink
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Philipp Eckert
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Peter Ruth
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Lukas Rüttiger
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Marlies Knipper
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
- *Correspondence: Marlies Knipper
| | - Wibke Singer
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
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The protective effects of systemic dexamethasone on sensory epithelial damage and hearing loss in targeted Cx26-null mice. Cell Death Dis 2022; 13:545. [PMID: 35688810 PMCID: PMC9187686 DOI: 10.1038/s41419-022-04987-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 05/25/2022] [Accepted: 05/30/2022] [Indexed: 01/21/2023]
Abstract
Mutations in the GJB2 gene (encoding Connexin26(Cx26)) are the most common cause of hereditary deafness, accounting for about a quarter of all cases. Sensory epithelial damage is considered to be one of the main causes of deafness caused by GJB2 gene mutation. Dexamethasone (DEX) is widely used in the treatment of a variety of inner ear diseases including sudden sensorineural hearing loss (SSNHL), noise-induced hearing loss (NIHL), and deafness caused by ototoxic drugs. Whether DEX has a direct therapeutic effect on hereditary deafness, especially GJB2-related deafness, remains unclear. In this study, we revealed that DEX can effectively prevent hair cell death caused by oxidative stress in cochlear explants. Additionally, two distinct Cx26-null mouse models were established to investigate whether systemic administration of DEX alleviate the cochlear sensory epithelial injury or deafness in these models. In a specific longitudinally Cx26-null model that does not cause deafness, systemic administration of DEX prevents the degeneration of outer hair cells (OHCs) induced by Cx26 knockout. Similarly, in a targeted-Deiter's cells (DCs) Cx26-null mouse model that causes deafness, treatment with DEX can almost completely prevent OHCs loss and alleviates auditory threshold shifts at some frequencies. Additionally, we observed that DEX inhibited the recruitment of CD45-positive cells in the targeted-DCs Cx26-null mice. Taken together, our results suggest that the protective effect of dexamethasone on cochlear sensory epithelial damage and partially rescue auditory function may be related to the regulation of inner ear immune response in Cx26 deficiency mouse models.
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Harrison RT, DeBacker JR, Trevino M, Bielefeld EC, Lobarinas E. Cochlear Preconditioning as a Modulator of Susceptibility to Hearing Loss. Antioxid Redox Signal 2022; 36:1215-1228. [PMID: 34011160 DOI: 10.1089/ars.2021.0055] [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] [Indexed: 11/12/2022]
Abstract
Significance: Acquired sensorineural hearing loss is a major public health problem worldwide. The leading causes of sensorineural hearing loss are noise, aging, and ototoxic medications, with the key underlying pathology being damage to the cochlea. The review focuses on the phenomenon of preconditioning, in which the susceptibility to cochlear injury is reduced by exposing the ear to a stressful stimulus. Recent Advances: Cochlear conditioning has focused on the use of mono-modal conditioning, specifically conditioning the cochlea with moderate noise exposures before a traumatic exposure that causes permanent hearing loss. Recently, cross-modal conditioning has been explored more thoroughly, to prevent not only noise-induced hearing loss, but also age-related and drug-induced hearing losses. Critical Issues: Noise exposures that cause only temporary threshold shifts (TTSs) can cause long-term synaptopathy, injury to the synapses between the inner hair cells and spiral ganglion cells. This discovery has the potential to significantly alter the field of cochlear preconditioning with noise. Further, cochlear preconditioning can be the gateway to the development of clinically deployable therapeutics. Therefore, understanding the underlying mechanisms of conditioning is crucial for optimizing clinical protection against sensorineural hearing loss. Future Directions: Before the discovery of synaptopathy, noise exposures that caused only TTSs were believed to be either harmless or potentially beneficial. Any considerations of preconditioning with noise must consider the potential for injury to the synapses. Further, the discovery of different methods to precondition the cochlea against injury will yield new avenues for protection against hearing loss in the vulnerable populations. Antioxid. Redox Signal. 36, 1215-1228.
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Affiliation(s)
- Ryan T Harrison
- Department of Speech and Hearing Science, The Ohio State University, Columbus, Ohio, USA
| | - J Riley DeBacker
- Department of Speech and Hearing Science, The Ohio State University, Columbus, Ohio, USA
| | - Monica Trevino
- Callier Center for Communication Disorders, School of Behavioral and Brain Sciences, The University of Texas at Dallas, Dallas, Texas, USA
| | - Eric C Bielefeld
- Department of Speech and Hearing Science, The Ohio State University, Columbus, Ohio, USA
| | - Edward Lobarinas
- Callier Center for Communication Disorders, School of Behavioral and Brain Sciences, The University of Texas at Dallas, Dallas, Texas, USA
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10
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Luo J, Lin X, Li L, Tan J, Li P. β-Cyclodextrin and Oligoarginine Peptide-Based Dendrimer-Entrapped Gold Nanoparticles for Improving Drug Delivery to the Inner Ear. Front Bioeng Biotechnol 2022; 10:844177. [PMID: 35480970 PMCID: PMC9038081 DOI: 10.3389/fbioe.2022.844177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 02/24/2022] [Indexed: 11/13/2022] Open
Abstract
Here, we developed a safe and highly effective nanocarrier using β-cyclodextrin (β-CD) and oligoarginine peptide (Arg8)-modified dendrimer-entrapped gold nanoparticles (Au@CD-PAMAM-Arg8), with a diameter of 5 nm, for improved delivery of dexamethasone (Dex) to the inner ear. The properties and in vivo distribution of the Au@CD-PAMAM-Arg8 were assessed in vitro, and a streptomycin (SM) ototoxicity model was used in vivo. Flow cytometry analysis of HEIOC1 cells treated with Au@CD-PAMAM-Arg8 and Au @CD-PAMAM at different time intervals indicated that cell uptake efficiency of the drug delivery carrier Au@CD-PAMAM-Arg8 was higher than that of Au @CD-PAMAM. Au@CD-PAMAM-Arg8 carrying Dex (Au@CD-PAMAM-Arg8/Dex) were mainly distributed in hair cells, the spiral ganglion, lateral wall, and nerve fibers and had stronger protective effects on the inner ear than Dex administration alone. In vivo tracer tests revealed that tympanic injection was significantly more effective than posterior ear injection, muscle injection, and tail vein injection, whereas clinical retro-auricular injection could not increase the efficiency of drug delivery into the ear. Electrocochleography results showed that Au@CD-PAMAM-Arg8/Dex significantly improved hearing in C57/BL6 mice after SM exposure. These findings indicate that Au@CD-PAMAM-Arg8 may be the useful drug carriers for the treatment of inner ear diseases.
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Affiliation(s)
- Jia Luo
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - XueXin Lin
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - LiLing Li
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - JingQian Tan
- Department of Otolaryngology Head and Neck Surgery, The Eighth Affiliated Hospital of Sun Yat-Sen University, Shenzhen, China
| | - Peng Li
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
- *Correspondence: Peng Li,
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11
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Marchetta P, Eckert P, Lukowski R, Ruth P, Singer W, Rüttiger L, Knipper M. Loss of central mineralocorticoid or glucocorticoid receptors impacts auditory nerve processing in the cochlea. iScience 2022; 25:103981. [PMID: 35281733 PMCID: PMC8914323 DOI: 10.1016/j.isci.2022.103981] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/26/2022] [Accepted: 02/21/2022] [Indexed: 02/08/2023] Open
Abstract
The key auditory signature that may associate peripheral hearing with central auditory cognitive defects remains elusive. Suggesting the involvement of stress receptors, we here deleted the mineralocorticoid and glucocorticoid receptors (MR and GR) using a CaMKIIα-based tamoxifen-inducible CreERT2/loxP approach to generate mice with single or double deletion of central but not cochlear MR and GR. Hearing thresholds of MRGRCaMKIIαCreERT2 conditional knockouts (cKO) were unchanged, whereas auditory nerve fiber (ANF) responses were larger and faster and auditory steady state responses were improved. Subsequent analysis of single MR or GR cKO revealed discrete roles for both, central MR and GR on cochlear functions. Limbic MR deletion reduced inner hair cell (IHC) ribbon numbers and ANF responses. In contrast, GR deletion shortened the latency and improved the synchronization to amplitude-modulated tones without affecting IHC ribbon numbers. These findings imply that stress hormone-dependent functions of central MR/GR contribute to “precognitive” sound processing in the cochlea. Top-down MR/GR signaling differentially contributes to cochlear sound processing Limbic MR stimulates auditory nerve fiber discharge rates Central GR deteriorates auditory nerve fiber synchrony
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Affiliation(s)
- Philine Marchetta
- University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | - Philipp Eckert
- University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | - Robert Lukowski
- University of Tübingen, Institute of Pharmacy, Pharmacology, Toxicology and Clinical Pharmacy, 72076 Tübingen, Germany
| | - Peter Ruth
- University of Tübingen, Institute of Pharmacy, Pharmacology, Toxicology and Clinical Pharmacy, 72076 Tübingen, Germany
| | - Wibke Singer
- University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | - Lukas Rüttiger
- University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | - Marlies Knipper
- University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
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12
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Zhang L, Wang J, Sun H, Feng G, Gao Z. Interactions between the hippocampus and the auditory pathway. Neurobiol Learn Mem 2022; 189:107589. [DOI: 10.1016/j.nlm.2022.107589] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 01/12/2022] [Accepted: 01/29/2022] [Indexed: 12/22/2022]
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13
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Knipper M, Singer W, Schwabe K, Hagberg GE, Li Hegner Y, Rüttiger L, Braun C, Land R. Disturbed Balance of Inhibitory Signaling Links Hearing Loss and Cognition. Front Neural Circuits 2022; 15:785603. [PMID: 35069123 PMCID: PMC8770933 DOI: 10.3389/fncir.2021.785603] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 12/08/2021] [Indexed: 12/19/2022] Open
Abstract
Neuronal hyperexcitability in the central auditory pathway linked to reduced inhibitory activity is associated with numerous forms of hearing loss, including noise damage, age-dependent hearing loss, and deafness, as well as tinnitus or auditory processing deficits in autism spectrum disorder (ASD). In most cases, the reduced central inhibitory activity and the accompanying hyperexcitability are interpreted as an active compensatory response to the absence of synaptic activity, linked to increased central neural gain control (increased output activity relative to reduced input). We here suggest that hyperexcitability also could be related to an immaturity or impairment of tonic inhibitory strength that typically develops in an activity-dependent process in the ascending auditory pathway with auditory experience. In these cases, high-SR auditory nerve fibers, which are critical for the shortest latencies and lowest sound thresholds, may have either not matured (possibly in congenital deafness or autism) or are dysfunctional (possibly after sudden, stressful auditory trauma or age-dependent hearing loss linked with cognitive decline). Fast auditory processing deficits can occur despite maintained basal hearing. In that case, tonic inhibitory strength is reduced in ascending auditory nuclei, and fast inhibitory parvalbumin positive interneuron (PV-IN) dendrites are diminished in auditory and frontal brain regions. This leads to deficits in central neural gain control linked to hippocampal LTP/LTD deficiencies, cognitive deficits, and unbalanced extra-hypothalamic stress control. Under these conditions, a diminished inhibitory strength may weaken local neuronal coupling to homeostatic vascular responses required for the metabolic support of auditory adjustment processes. We emphasize the need to distinguish these two states of excitatory/inhibitory imbalance in hearing disorders: (i) Under conditions of preserved fast auditory processing and sustained tonic inhibitory strength, an excitatory/inhibitory imbalance following auditory deprivation can maintain precise hearing through a memory linked, transient disinhibition that leads to enhanced spiking fidelity (central neural gain⇑) (ii) Under conditions of critically diminished fast auditory processing and reduced tonic inhibitory strength, hyperexcitability can be part of an increased synchronization over a broader frequency range, linked to reduced spiking reliability (central neural gain⇓). This latter stage mutually reinforces diminished metabolic support for auditory adjustment processes, increasing the risks for canonical dementia syndromes.
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Affiliation(s)
- Marlies Knipper
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
- *Correspondence: Marlies Knipper,
| | - Wibke Singer
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Kerstin Schwabe
- Experimental Neurosurgery, Department of Neurosurgery, Hannover Medical School, Hanover, Germany
| | - Gisela E. Hagberg
- Department of Biomedical Magnetic Resonance, University Hospital Tübingen (UKT), Tübingen, Germany
- High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Yiwen Li Hegner
- MEG Center, University of Tübingen, Tübingen, Germany
- Center of Neurology, Hertie-Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Lukas Rüttiger
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Christoph Braun
- MEG Center, University of Tübingen, Tübingen, Germany
- Center of Neurology, Hertie-Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Rüdiger Land
- Department of Experimental Otology, Institute for Audioneurotechnology, Hannover Medical School, Hanover, Germany
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Ng L, Liu Y, Liu H, Forrest D. Cochlear Fibrocyte and Osteoblast Lineages Expressing Type 2 Deiodinase Identified with a Dio2CreERt2 Allele. Endocrinology 2021; 162:bqab179. [PMID: 34436572 PMCID: PMC8475715 DOI: 10.1210/endocr/bqab179] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Indexed: 12/16/2022]
Abstract
Type 2 deiodinase (Dio2) amplifies levels of 3,5,3'-L-triiodothyronine (T3), the active form of thyroid hormone, and is essential for cochlear maturation and auditory development. However, cellular routes for endocrine signaling in the compartmentalized, anatomically complex cochlea are little understood. Dio2 generates T3 from thyroxine (T4), a more abundant thyroid hormone precursor in the circulation, and is dramatically induced in the cochlea before the onset of hearing. The evidence implies that specific Dio2-expressing cell types critically mediate T3 signaling but these cell types are poorly defined because Dio2 is expressed transiently at low levels. Here, using a Dio2CreERt2 knockin that activates a fluorescent reporter, we define Dio2-expressing cochlear cell types at high resolution in male or female mice. Dio2-positive cells were detected in vascularized supporting tissues but not in avascular internal epithelia, indicating segregation of T3-generating and T3-responding tissues. In the spiral ligament and spiral limbus, Dio2-positive fibrocytes clustered around vascular networks that convey T4 into cochlear tissues. In the otic capsule, Dio2-positive osteoblasts localized at cartilage surfaces as the bony labyrinth matures. We corroborated the identities of Dio2-positive lineages by RNA-sequencing of individual cells. The results suggest a previously unrecognized role for fibrocytes in mediating hormonal signaling. We discuss a model whereby fibrocytes mediate paracrine-like control of T3 signaling to the organ of Corti and epithelial target tissues.
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Affiliation(s)
- Lily Ng
- Laboratory of Endocrinology and Receptor Biology, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ye Liu
- Laboratory of Endocrinology and Receptor Biology, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA
| | - Hong Liu
- Laboratory of Endocrinology and Receptor Biology, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA
| | - Douglas Forrest
- Laboratory of Endocrinology and Receptor Biology, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA
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15
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Lee CJ, Chen HC, Shih CP, Lin YY, Kuo CY, Liu SC. Combined Acupuncture-Hyperbaric Oxygen-Steroids Therapy for Idiopathic Sudden Sensorineural Hearing Loss: A Retrospective Observational Study. J Altern Complement Med 2021; 27:588-595. [PMID: 33945302 DOI: 10.1089/acm.2020.0330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Objectives: Acupuncture, widely used in Chinese society, has been studied as an adjunct treatment of idiopathic sudden sensorineural hearing loss (ISSNHL). The purpose of this study is to investigate the effectiveness of combined acupuncture and hyperbaric oxygen therapy (HBOT) with conventional steroid therapy for ISSNHL. Methods: This retrospective chart review enrolled 154 patients who met the ISSNHL criteria and were categorized into three groups according to the different treatment regimens. Among these patients, 43 underwent steroid therapy only (S) group, 74 received steroid and HBOT (S-H) group, and the remaining 37 were treated with combined acupuncture-HBOT in addition to steroid therapy (S-H-A) group. The outcome was determined by comparing the differences in pure-tone thresholds and absolute hearing gains after treatment calculated at each audiometric octave frequency or grouped frequencies of audiograms. Hearing recoveries classified into three grades: complete, partial, and poor were also analyzed and compared among different treatment groups. Results: All subjects presented with initial severe hearing loss with averaged hearing thresholds >70 dB. The S-H-A group exhibited good hearing improvement outcomes at each audiometric octave frequency and grouped frequencies of audiograms, with greater hearing gain and had more favorable outcomes in hearing recovery grades compared with the S group and the S-H group. Conclusions: The results obtained in this study revealed a preliminary finding of ISSNHL patients benefiting from combined acupuncture, HBOT, and conventional steroid therapy. Acupuncture is a safe and nonpharmacologic treatment option and can be considered as an initial treatment strategy in such a clinical scenario.
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Affiliation(s)
- Che-Jui Lee
- Department of Otolaryngology-Head and Neck Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Hsin-Chien Chen
- Department of Otolaryngology-Head and Neck Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Cheng-Ping Shih
- Department of Otolaryngology-Head and Neck Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Yuan-Yung Lin
- Department of Otolaryngology-Head and Neck Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Chao-Yin Kuo
- Department of Otolaryngology-Head and Neck Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Shao-Cheng Liu
- Department of Otolaryngology-Head and Neck Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
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16
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The Physiologic Role of Corticosteroids in Menière's Disease: An Update on Glucocorticoid-mediated Pathophysiology and Corticosteroid Inner Ear Distribution. Otol Neurotol 2021; 41:271-276. [PMID: 31821251 DOI: 10.1097/mao.0000000000002467] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
: There are multiple treatment options for Ménière's disease (MD), including dietary modifications, aminoglycoside therapy, and surgery. All have limitations, ranging from limited effectiveness to permanent hearing loss. Corticosteroids have long been used to manage MD due to their relative efficacy and tolerability, but the exact mechanism for disease alleviation is uncertain. Until recently, the precise distribution and role that glucocorticoid receptors play in inner ear diseases have remained largely uninvestigated. Several studies propose they influence mechanisms of fluid regulation through ion and water homeostasis. This review will provide an update on the basic science literature describing the activity of endogenous glucocorticoids and exogenous corticosteroids in the inner ear and the relevance to MD, as well as early clinical trial data pertaining to the application of novel technologies for more effective administration of corticosteroids for the treatment of MD.
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Mansour M, Abo El Ezz TA, Fattoh FN, AbouelFadl DM, Gad HA. Delineating the usage of dexamethasone-loaded cubosomes as a therapeutic armamentarium for hearing loss versus its protective effect: In-vitro and in-vivo animal study. J Drug Deliv Sci Technol 2021. [DOI: 10.1016/j.jddst.2020.102244] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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18
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Domarecka E, Olze H, Szczepek AJ. Auditory Brainstem Responses (ABR) of Rats during Experimentally Induced Tinnitus: Literature Review. Brain Sci 2020; 10:brainsci10120901. [PMID: 33255266 PMCID: PMC7760291 DOI: 10.3390/brainsci10120901] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/16/2020] [Accepted: 11/21/2020] [Indexed: 12/31/2022] Open
Abstract
Tinnitus is a subjective phantom sound perceived only by the affected person and a symptom of various auditory and non-auditory conditions. The majority of methods used in clinical and basic research for tinnitus diagnosis are subjective. To better understand tinnitus-associated changes in the auditory system, an objective technique measuring auditory sensitivity-the auditory brainstem responses (ABR)-has been suggested. Therefore, the present review aimed to summarize ABR's features in a rat model during experimentally induced tinnitus. PubMed, Web of Science, Science Direct, and Scopus databanks were searched using Medical Subject Heading (MeSH) terms: auditory brainstem response, tinnitus, rat. The search identified 344 articles, and 36 of them were selected for the full-text analyses. The experimental protocols and results were evaluated, and the gained knowledge was synthesized. A high level of heterogeneity between the studies was found regarding all assessed areas. The most consistent finding of all studies was a reduction in the ABR wave I amplitude following exposure to noise and salicylate. Simultaneously, animals with salicylate-induced but not noise-induced tinnitus had an increased amplitude of wave IV. Furthermore, the present study identified a need to develop a consensus experimental ABR protocol applied in future tinnitus studies using the rat model.
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Affiliation(s)
- Ewa Domarecka
- Department of Otorhinolaryngology, Head and Neck Surgery, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10117 Berlin, Germany; (E.D.); (H.O.)
| | - Heidi Olze
- Department of Otorhinolaryngology, Head and Neck Surgery, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10117 Berlin, Germany; (E.D.); (H.O.)
| | - Agnieszka J. Szczepek
- Department of Otorhinolaryngology, Head and Neck Surgery, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10117 Berlin, Germany; (E.D.); (H.O.)
- Faculty of Medicine and Health Sciences, University of Zielona Gora, 65-046 Zielona Gora, Poland
- Correspondence:
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19
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Yang CH, Hwang CF, Chuang JH, Lian WS, Wang FS, Huang EI, Yang MY. Constant Light Dysregulates Cochlear Circadian Clock and Exacerbates Noise-Induced Hearing Loss. Int J Mol Sci 2020; 21:E7535. [PMID: 33066038 PMCID: PMC7589695 DOI: 10.3390/ijms21207535] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 09/30/2020] [Accepted: 10/09/2020] [Indexed: 02/08/2023] Open
Abstract
Noise-induced hearing loss is one of the major causes of acquired sensorineural hearing loss in modern society. While people with excessive exposure to noise are frequently the population with a lifestyle of irregular circadian rhythms, the effects of circadian dysregulation on the auditory system are still little known. Here, we disturbed the circadian clock in the cochlea of male CBA/CaJ mice by constant light (LL) or constant dark. LL significantly repressed circadian rhythmicity of circadian clock genes Per1, Per2, Rev-erbα, Bmal1, and Clock in the cochlea, whereas the auditory brainstem response thresholds were unaffected. After exposure to low-intensity (92 dB) noise, mice under LL condition initially showed similar temporary threshold shifts to mice under normal light-dark cycle, and mice under both conditions returned to normal thresholds after 3 weeks. However, LL augmented high-intensity (106 dB) noise-induced permanent threshold shifts, particularly at 32 kHz. The loss of outer hair cells (OHCs) and the reduction of synaptic ribbons were also higher in mice under LL after noise exposure. Additionally, LL enhanced high-intensity noise-induced 4-hydroxynonenal in the OHCs. Our findings convey new insight into the deleterious effect of an irregular biological clock on the auditory system.
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Affiliation(s)
- Chao-Hui Yang
- Department of Otolaryngology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan;
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 33302, Taiwan; (J.-H.C.); (F.-S.W.)
| | - Chung-Feng Hwang
- Department of Otolaryngology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan;
| | - Jiin-Haur Chuang
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 33302, Taiwan; (J.-H.C.); (F.-S.W.)
- Division of Pediatric Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan
| | - Wei-Shiung Lian
- Core Laboratory for Phenomics & Diagnostics, Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan;
| | - Feng-Sheng Wang
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 33302, Taiwan; (J.-H.C.); (F.-S.W.)
- Core Laboratory for Phenomics & Diagnostics, Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan;
| | - Ethan I. Huang
- Department of Otolaryngology, Chang Gung Memorial Hospital, Chiayi 61363, Taiwan;
| | - Ming-Yu Yang
- Department of Otolaryngology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan;
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 33302, Taiwan; (J.-H.C.); (F.-S.W.)
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Hsp70/Bmi1-FoxO1-SOD Signaling Pathway Contributes to the Protective Effect of Sound Conditioning against Acute Acoustic Trauma in a Rat Model. Neural Plast 2020; 2020:8823785. [PMID: 33082778 PMCID: PMC7556106 DOI: 10.1155/2020/8823785] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 07/27/2020] [Accepted: 08/05/2020] [Indexed: 02/06/2023] Open
Abstract
Sound conditioning (SC) is defined as “toughening” to lower levels of sound over time, which reduces a subsequent noise-induced threshold shift. Although the protective effect of SC in mammals is generally understood, the exact mechanisms involved have not yet been elucidated. To confirm the protective effect of SC against noise exposure (NE) and the stress-related signaling pathway of its rescue, we observed target molecule changes caused by SC of low frequency prior to NE as well as histology analysis in vivo and verified the suggested mechanisms in SGNs in vitro. Further, we investigated the potential role of Hsp70 and Bmi1 in SC by targeting SOD1 and SOD2 which are regulated by the FoxO1 signaling pathway based on mitochondrial function and reactive oxygen species (ROS) levels. Finally, we sought to identify the possible molecular mechanisms associated with the beneficial effects of SC against noise-induced trauma. Data from the rat model were evaluated by western blot, immunofluorescence, and RT-PCR. The results revealed that SC upregulated Hsp70, Bmi1, FoxO1, SOD1, and SOD2 expression in spiral ganglion neurons (SGNs). Moreover, the auditory brainstem responses (ABRs) and electron microscopy revealed that SC could protect against acute acoustic trauma (AAT) based on a significant reduction of hearing impairment and visible reduction in outer hair cell loss as well as ultrastructural changes in OHCs and SGNs. Collectively, these results suggested that the contribution of Bmi1 toward decreased sensitivity to noise-induced trauma following SC was triggered by Hsp70 induction and associated with enhancement of the antioxidant system and decreased mitochondrial superoxide accumulation. This contribution of Bmi1 was achieved by direct targeting of SOD1 and SOD2, which was regulated by FoxO1. Therefore, the Hsp70/Bmi1-FoxO1-SOD signaling pathway might contribute to the protective effect of SC against AAT in a rat model.
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21
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Xu X, Lin K, Wang Y, Xu K, Sun Y, Yang X, Yang M, He Z, Zhang Y, Zheng H, Chen X. A metal-organic framework based inner ear delivery system for the treatment of noise-induced hearing loss. NANOSCALE 2020; 12:16359-16365. [PMID: 32725028 DOI: 10.1039/d0nr04860g] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Noise-induced hearing loss (NIHL) is associated with both acute and chronic noise exposure. The application of steroid hormones is the first-line treatment for NIHL. However, a high dose of steroid hormone in the body is necessary to maintain its efficacy and causes side effects, such as headache and osteoporosis. In this work, we prepared a zeolitic imidazolate framework (ZIF)-based system for steroid hormone delivery in the inner ear. Methylprednisolone (MP), a typical steroid hormone, was encapsulated into ZIF-90 nanoparticles (NPs) using one-pot synthesis method. The obtained MP@ZIF-90 NPs are negatively charged and 120 nm in size and showed good biocompatibility and stability at a pH value of 7.4. After intraperitoneal injection, ZIF-90 could efficiently protect drugs during peripheral blood circulation, enter the inner ear via the blood labyrinthine barrier (BLB) and slowly release the drugs. Auditory brainstem response (ABR) tests indicated that MP@ZIF-90 exhibits better protection of mice from noise than those using the free MP and ZIF-8 with encapsulated MP (MP@ZIF-8). More importantly, MP@ZIF-90 showed no defects to the inner ear after being treated for noise and low nephrotoxicity during therapy, which demonstrates the biocompatibility of this material. We believe the ZIF-90 based delivery system is an efficient strategy for inner ear therapy of NIHL.
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Affiliation(s)
- Xiaoxiang Xu
- Department of Otorhinolaryngology-Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China.
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Yu YF, Zhang YM, Shi C, Pan C. The role of caloric testing and the vestibular evoked myogenic potential in the efficacy of intratympanic dexamethasone injection in 201 patients with unilateral Meniere's disease. Clin Otolaryngol 2020; 45:634-642. [PMID: 32304344 DOI: 10.1111/coa.13552] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 04/05/2020] [Accepted: 04/13/2020] [Indexed: 11/28/2022]
Affiliation(s)
- Ya-Feng Yu
- Department of Otolaryngology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Yun-Mei Zhang
- Department of Otolaryngology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Chen Shi
- Department of Otolaryngology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Chen Pan
- Department of Otolaryngology, The First Affiliated Hospital of Soochow University, Suzhou, China
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Li P, Bing D, Wang S, Chen J, Du Z, Sun Y, Qi F, Zhang Y, Chu H. Sleep Deprivation Modifies Noise-Induced Cochlear Injury Related to the Stress Hormone and Autophagy in Female Mice. Front Neurosci 2019; 13:1297. [PMID: 31849600 PMCID: PMC6896935 DOI: 10.3389/fnins.2019.01297] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 11/18/2019] [Indexed: 12/20/2022] Open
Abstract
A lack of sleep is linked with a range of inner ear diseases, including hearing loss and tinnitus. Here, we used a mouse model to investigate the effects of sleep deprivation (SD) on noise vulnerability, and explored the mechanisms that might be involved in vitro, focusing particularly corticosterone levels and autophagic flux in cells. Female BALB/c mice were divided into six groups [control, acoustic trauma (AT)-alone, 1 day (d) SD-alone, 1d SD pre-AT, 5d SD-alone, and 5d SD pre-AT]. Cochlear damage was then assessed by analyzing auditory brainstem response (ABR), and by counting outer hair cells (OHCs) and the synaptic ribbons of inner hair cells (IHCs). In addition, we measured levels of serum corticosterone and autophagy protein expression in the basilar membranes by ELISA kits, and western blotting, respectively. We found that SD-alone temporarily elevated ABR wave I amplitude, but had no permanent effect on hearing level or IHC ribbon numbers. Combined with AT, the number of synaptic ribbons in the 1d SD pre-AT group was significantly higher than that in the AT-alone group, whereas the 5d SD pre-AT group showed more severe synaptopathy, and a greater loss of OHCs after 2 weeks than the other experimental groups exposed to noise. Correspondingly, the levels of corticosterone in the AT-alone group were higher than those of the 1d SD pre-AT group, but lower than those of the 5d SD pre-AT group. The 1d SD pre-AT group showed a marked elevation in the expression of microtubule-associated protein 1 light chain 3B (LC3B), whereas the AT-alone group exhibited only a mild increase. In contrast, the levels of LC3B did not change in the 5d SD pre-AT group. Experiments with HEI-OC-1 cells and cochlear basilar membrane cultures showed that high-concentrations of dexamethasone, and the inhibition of autophagy, aggravated cellular apoptosis induced by oxidative stress. In conclusion, noise-induced synaptopathy and hair cell loss can be mitigated by preceding 1d SD, but will be aggravated by preceding 5d SD. These findings may be attributable to corticosterone levels and the extent of autophagy.
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Affiliation(s)
- Pengjun Li
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Dan Bing
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Sumei Wang
- Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jin Chen
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhihui Du
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yanbo Sun
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Fan Qi
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yingmiao Zhang
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, China
| | - Hanqi Chu
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Solid Lipid Nanoparticles Loaded with Glucocorticoids Protect Auditory Cells from Cisplatin-Induced Ototoxicity. J Clin Med 2019; 8:jcm8091464. [PMID: 31540035 PMCID: PMC6780793 DOI: 10.3390/jcm8091464] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 08/23/2019] [Accepted: 09/12/2019] [Indexed: 12/18/2022] Open
Abstract
Cisplatin is a chemotherapeutic agent that causes the irreversible death of auditory sensory cells, leading to hearing loss. Local administration of cytoprotective drugs is a potentially better option co-therapy for cisplatin, but there are strong limitations due to the difficulty of accessing the inner ear. The use of nanocarriers for the efficient delivery of drugs to auditory cells is a novel approach for this problem. Solid lipid nanoparticles (SLNs) are biodegradable and biocompatible nanocarriers with low solubility in aqueous media. We show here that stearic acid-based SLNs have the adequate particle size, polydispersity index and ζ-potential, to be considered optimal nanocarriers for drug delivery. Stearic acid-based SLNs were loaded with the fluorescent probe rhodamine to show that they are efficiently incorporated by auditory HEI-OC1 (House Ear Institute-Organ of Corti 1) cells. SLNs were not ototoxic over a wide dose range. Glucocorticoids are used to decrease cisplatin-induced ototoxicity. Therefore, to test SLNs’ drug delivery efficiency, dexamethasone and hydrocortisone were tested either alone or loaded into SLNs and tested in a cisplatin-induced ototoxicity in vitro assay. Our results indicate that the encapsulation in SLNs increases the protective effect of low doses of hydrocortisone and lengthens the survival of HEI-OC1 cells treated with cisplatin.
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Cochlear Glucocorticoid Receptor and Serum Corticosterone Expression in a Rodent Model of Noise-induced Hearing Loss: Comparison of Timing of Dexamethasone Administration. Sci Rep 2019; 9:12646. [PMID: 31477769 PMCID: PMC6718671 DOI: 10.1038/s41598-019-49133-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 08/14/2019] [Indexed: 12/20/2022] Open
Abstract
Glucocorticoid (GC) is a steroid hormone secreted from the adrenal cortex in response to stress, which acts by binding to cytoplasmic glucocorticoid receptors (GRs). Dexamethasone (DEX) is a synthetic GC exhibiting immunosuppressive effects in both human and rodent models of hearing loss. While clinical evidence has shown the effectiveness of DEX for treatment of various inner ear diseases, its mechanisms of action and the optimal timing of treatment are not well understood. In the present study, intergroup comparisons were conducted based on the time point of treatment with DEX: (1) pretreatment; (2) posttreatment; and (3) pre&post-noise. The pre&post DEX treatment group showed a significant improvement in threshold shift at 1 day post-noise exposure as compared to the TTS (transient threshold shift)-only group at 8 and 16 kHz. Both TTS and PTS (permanent threshold shift) significantly reduced cochlear GR mRNA expression and increased serum corticosterone and cochlear inflammatory cytokines. The pre&post DEX treatment group showed a significant decrease in serum corticosterone level as compared to other DEX treatment groups and TTS-treated group at 3 days after acoustic trauma. Our results suggest that the timing of DEX administration differentially modulates systemic steroid levels, GR expression and cochlear cytokine expression.
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26
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Cederroth CR, Park JS, Basinou V, Weger BD, Tserga E, Sarlus H, Magnusson AK, Kadri N, Gachon F, Canlon B. Circadian Regulation of Cochlear Sensitivity to Noise by Circulating Glucocorticoids. Curr Biol 2019; 29:2477-2487.e6. [PMID: 31353184 PMCID: PMC6904421 DOI: 10.1016/j.cub.2019.06.057] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 05/21/2019] [Accepted: 06/20/2019] [Indexed: 01/27/2023]
Abstract
The cochlea possesses a robust circadian clock machinery that regulates auditory function. How the cochlear clock is influenced by the circadian system remains unknown. Here, we show that cochlear rhythms are system driven and require local Bmal1 as well as central input from the suprachiasmatic nuclei (SCN). SCN ablations disrupted the circadian expression of the core clock genes in the cochlea. Because the circadian secretion of glucocorticoids (GCs) is controlled by the SCN and GCs are known to modulate auditory function, we assessed their influence on circadian gene expression. Removal of circulating GCs by adrenalectomy (ADX) did not have a major impact on core clock gene expression in the cochlea. Rather it abolished the transcription of clock-controlled genes involved in inflammation. ADX abolished the known differential auditory sensitivity to day and night noise trauma and prevented the induction of GABA-ergic and glutamate receptors mRNA transcripts. However, these improvements were unrelated to changes at the synaptic level, suggesting other cochlear functions may be involved. Due to this circadian regulation of noise sensitivity by GCs, we evaluated the actions of the synthetic glucocorticoid dexamethasone (DEX) at different times of the day. DEX was effective in protecting from acute noise trauma only when administered during daytime, when circulating glucocorticoids are low, indicating that chronopharmacological approaches are important for obtaining optimal treatment strategies for hearing loss. GCs appear as a major regulator of the differential sensitivity to day or night noise trauma, a mechanism likely involving the circadian control of inflammatory responses.
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Affiliation(s)
| | - Jung-Sub Park
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm 17177, Sweden; Department of Otolaryngology, Ajou University School of Medicine, 164, Worldcup-ro, Yeongtong-gu, Suwon 16499, Korea
| | - Vasiliki Basinou
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm 17177, Sweden
| | - Benjamin D Weger
- Department of Diabetes and Circadian Rhythms, Nestlé Institute of Health Sciences, 1015 Lausanne, Switzerland
| | - Evangelia Tserga
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm 17177, Sweden
| | - Heela Sarlus
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm 17177, Sweden
| | - Anna K Magnusson
- Department of Clinical Science Intervention and Technology, Karolinska Institutet, Stockholm 17177, Sweden
| | - Nadir Kadri
- Department of Laboratory Medicine, Karolinska Institutet, Stockholm 17177, Sweden
| | - Frédéric Gachon
- Department of Diabetes and Circadian Rhythms, Nestlé Institute of Health Sciences, 1015 Lausanne, Switzerland; School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Barbara Canlon
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm 17177, Sweden
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Selleck AM, Park LR, Choudhury B, Teagle HFB, Woodard JS, Gagnon EB, Brown KD. Hearing Preservation in Pediatric Recipients of Cochlear Implants. Otol Neurotol 2019; 40:e277-e282. [DOI: 10.1097/mao.0000000000002120] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
Sensorineural hearing impairment is the most common sensory disorder and a major health and socio-economic issue in industrialized countries. It is primarily due to the degeneration of mechanosensory hair cells and spiral ganglion neurons in the cochlea via complex pathophysiological mechanisms. These occur following acute and/or chronic exposure to harmful extrinsic (e.g., ototoxic drugs, noise...) and intrinsic (e.g., aging, genetic) causative factors. No clinical therapies currently exist to rescue the dying sensorineural cells or regenerate these cells once lost. Recent studies have, however, provided renewed hope, with insights into the therapeutic targets allowing the prevention and treatment of ototoxic drug- and noise-induced, age-related hearing loss as well as cochlear cell degeneration. Moreover, genetic routes involving the replacement or corrective editing of mutant sequences or defected genes are showing promise, as are cell-replacement therapies to repair damaged cells for the future restoration of hearing in deaf people. This review begins by recapitulating our current understanding of the molecular pathways that underlie cochlear sensorineural damage, as well as the survival signaling pathways that can provide endogenous protection and tissue rescue. It then guides the reader through to the recent discoveries in pharmacological, gene and cell therapy research towards hearing protection and restoration as well as their potential clinical application.
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Affiliation(s)
- Jing Wang
- INSERM UMR 1051, Institute for Neurosciences of Montpellier, Montpellier, France; and University of Montpellier, Montpellier, France
| | - Jean-Luc Puel
- INSERM UMR 1051, Institute for Neurosciences of Montpellier, Montpellier, France; and University of Montpellier, Montpellier, France
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Mutlu A, Ocal FCA, Erbek S, Ozluoglu L. The protective effect of adrenocorticotropic hormone treatment against noise-induced hearing loss. Auris Nasus Larynx 2018; 45:929-935. [DOI: 10.1016/j.anl.2017.12.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 11/27/2017] [Accepted: 12/13/2017] [Indexed: 10/17/2022]
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Rujescu D, Hartmann AM, Giegling I, Konte B, Herrling M, Himmelein S, Strupp M. Genome-Wide Association Study in Vestibular Neuritis: Involvement of the Host Factor for HSV-1 Replication. Front Neurol 2018; 9:591. [PMID: 30079052 PMCID: PMC6062961 DOI: 10.3389/fneur.2018.00591] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 07/02/2018] [Indexed: 12/11/2022] Open
Abstract
Objective: In order to identify genetic variants associated with vestibular neuritis, a common cause of peripheral vertigo with a potential causative link to the reactivation of herpes simplex type 1 (HSV-1), we conducted a genome-wide association study. Methods: Association was assessed using approximately 8 million variants. 131 patients with vestibular neuritis and 2,609 controls of European ancestry were included. Results: Genome-wide associations with vestibular neuritis were detected in 4 regions containing protein coding genes assignable to two functional groups: virus hypothesis and insulin metabolism. Genes of set 1 are related to viral processes: nuclear receptor subfamily 3 group C member 2 (NR3C2) is a receptor for mineralocorticoids and glucocorticoids and was shown to be a host factor for HSV-1 replication. Ankyrin repeat domain 30A (ANKRD30A) encodes a host factor for human immunodeficiency virus-1 (HIV-1) infection. It shows rapid evolution and is induced by interferon stimulation. Mediator complex 30 (MED30), an important member of the mediator complex, has been shown to be involved in replication of HIV-1, a knockdown leading to impaired viral replication. The second set of genes LIM homeobox transcription factor 1 alpha (LMX1A), solute carrier family 30 member 8 (SLC30A8) is associated with insulin metabolism and resistance, a feature of some patients in whom type 2 diabetes is an accompanying comorbidity of vestibular neuritis. Conclusions: Using a GWAS approach to evaluate the etiology of vestibular neuritis these findings provide another piece of evidence that it may be caused by a viral inflammation.
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Affiliation(s)
- Dan Rujescu
- German Center for Vertigo and Balance Disorders, University Hospital Munich, Munich, Germany.,Department of Psychiatry, Psychotherapy and Psychosomatics, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Annette M Hartmann
- Department of Psychiatry, Psychotherapy and Psychosomatics, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Ina Giegling
- German Center for Vertigo and Balance Disorders, University Hospital Munich, Munich, Germany.,Department of Psychiatry, Psychotherapy and Psychosomatics, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Bettina Konte
- Department of Psychiatry, Psychotherapy and Psychosomatics, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Marko Herrling
- German Center for Vertigo and Balance Disorders, University Hospital Munich, Munich, Germany
| | - Susanne Himmelein
- German Center for Vertigo and Balance Disorders, University Hospital Munich, Munich, Germany.,Department of Neurology, University Hospital Munich, Munich, Germany
| | - Michael Strupp
- German Center for Vertigo and Balance Disorders, University Hospital Munich, Munich, Germany.,Department of Neurology, University Hospital Munich, Munich, Germany
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Sutton L, Schartinger V, Url C, Schmutzhard J, Lechner D, Kavasogullari C, Sandhu JS, Shaida A, Laszig R, Loehler J, Plontke S, Riechelmann H, Lechner M. Intratympanic steroid use for idiopathic sudden sensorineural hearing loss: current otolaryngology practice in Germany and Austria. Eur Arch Otorhinolaryngol 2018; 275:1103-1110. [PMID: 29605865 DOI: 10.1007/s00405-018-4958-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/27/2018] [Indexed: 01/23/2023]
Abstract
AIMS The frequency of the use of intratympanic steroids (ITS) as a treatment for idiopathic sudden sensorineural hearing loss (ISSNHL) in Europe is still unknown and remains a contentious issue amongst otolaryngologists. We undertook a survey of otolaryngologists in Germany and Austria to establish if there is any professional consensus with which to form a protocol for its use. METHODS A survey of 21 questions was distributed electronically to otolaryngologists in Germany and Austria and data on demographics, indications for intratympanic treatment, procedure, follow-up, and outcomes were analysed. RESULTS We received 908 responses. 49.1% of otolaryngologists used ITS for ISSNHL. Of those otolaryngologists who use ITS, 73.7% do not use it as primary treatment. 20.6% use ITS in conjunction with oral steroids for primary treatment and only 5.8% use ITS as monotherapy for primary treatment. 90.5% use ITS as salvage therapy. 81.1% do not consider the use of ITS after 2 weeks from the onset of symptoms. 8.3% used a tympanostomy tube and while the most commonly used steroid was dexamethasone at a concentration of 4 mg/ml (61%), a wide variety or other steroids and concentrations were used. CONCLUSIONS This survey illustrates wide variation of current practice of intratympanic corticosteroid injection for ISSHL in Germany and Austria. In the absence of high-level evidence, knowing what current practice is allows clinicians to assess what they do against what their colleagues are doing, and if they do something very different, make them question their practice. Moreover, the obtained data will help to direct future clinical trials with the aim to compare the outcomes of more commonly used protocols.
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Affiliation(s)
- L Sutton
- Head and Neck Centre, University College London Hospitals NHS Trust, Euston Road, London, NW1 2PG, UK
- UCL Cancer Institute, University College London, 72 Huntley Street, London, WC1E 6DD, UK
| | - V Schartinger
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital of Innsbruck, Anichstr., Innsbruck, Austria
| | - C Url
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital of Innsbruck, Anichstr., Innsbruck, Austria
| | - J Schmutzhard
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital of Innsbruck, Anichstr., Innsbruck, Austria
| | - D Lechner
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital of Innsbruck, Anichstr., Innsbruck, Austria
| | | | - J S Sandhu
- Northern General Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, S5 7AT, UK
| | - A Shaida
- Royal National Throat, Nose and Ear Hospital, University College London Hospitals NHS Trust, 330 Grays Inn Road, London, WC1X 8DA, UK
| | - R Laszig
- Department of Otorhinolaryngology, University Hospital of Freiburg, Breisacher Str., Freiburg, Germany
| | - J Loehler
- ENT Clinic, Maienbeeck, Bad Bramstedt, Germany
| | - S Plontke
- Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Halle, Ernst-Grube-Str., Halle, Germany
| | - H Riechelmann
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital of Innsbruck, Anichstr., Innsbruck, Austria
| | - M Lechner
- Head and Neck Centre, University College London Hospitals NHS Trust, Euston Road, London, NW1 2PG, UK.
- UCL Cancer Institute, University College London, 72 Huntley Street, London, WC1E 6DD, UK.
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital of Innsbruck, Anichstr., Innsbruck, Austria.
- Royal National Throat, Nose and Ear Hospital, University College London Hospitals NHS Trust, 330 Grays Inn Road, London, WC1X 8DA, UK.
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Singer W, Kasini K, Manthey M, Eckert P, Armbruster P, Vogt MA, Jaumann M, Dotta M, Yamahara K, Harasztosi C, Zimmermann U, Knipper M, Rüttiger L. The glucocorticoid antagonist mifepristone attenuates sound-induced long-term deficits in auditory nerve response and central auditory processing in female rats. FASEB J 2018; 32:3005-3019. [PMID: 29401591 DOI: 10.1096/fj.201701041rrr] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Systemic corticosteroids have been the mainstay of treatment for various hearing disorders for more than 30 yr. Accordingly, numerous studies have described glucocorticoids (GCs) and stressors to be protective in the auditory organ against damage associated with a variety of health conditions, including noise exposure. Conversely, stressors are also predictive risk factors for hearing disorders. How both of these contrasting stress actions are linked has remained elusive. Here, we demonstrate that higher corticosterone levels during acoustic trauma in female rats is highly correlated with a decline of auditory fiber responses in high-frequency cochlear regions, and that hearing thresholds and the outer hair cell functions (distortion products of otoacoustic emissions) are left unaffected. Moreover, when GC receptor (GR) or mineralocorticoid receptor (MR) activation was antagonized by mifepristone or spironolactone, respectively, GR, but not MR, inhibition significantly and permanently attenuated trauma-induced effects on auditory fiber responses, including inner hair cell ribbon loss and related reductions of early and late auditory brainstem responses. These findings strongly imply that higher corticosterone stress levels profoundly impair auditory nerve processing, which may influence central auditory acuity. These changes are likely GR mediated as they are prevented by mifepristone.-Singer, W., Kasini, K., Manthey, M., Eckert, P., Armbruster, P., Vogt, M. A., Jaumann, M., Dotta, M., Yamahara, K., Harasztosi, C., Zimmermann, U., Knipper, M., Rüttiger, L. The glucocorticoid antagonist mifepristone attenuates sound-induced long-term deficits in auditory nerve response and central auditory processing in female rats.
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Affiliation(s)
- Wibke Singer
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
| | - Kamyar Kasini
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
| | - Marie Manthey
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
| | - Philipp Eckert
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
| | - Philipp Armbruster
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
| | - Miriam Annika Vogt
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
| | - Mirko Jaumann
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
| | - Michela Dotta
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
| | - Kohei Yamahara
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany.,Section of Physiological Acoustics and Communication, Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Csaba Harasztosi
- Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
| | - Ulrike Zimmermann
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
| | - Marlies Knipper
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
| | - Lukas Rüttiger
- Molecular Physiology of Hearing, Department of Otolaryngology, Tübingen Hearing Research Centre, University of Tübingen, Tübingen, Germany
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Abstract
Local drug application to the inner ear offers a number of advantages over systemic delivery. Local drug therapy currently encompasses extracochlear administration (i. e., through intratympanic injection), intracochlear administration (particularly for gene and stem cell therapy), as well as various combinations with auditory neurosensory prostheses, either evaluated in preclinical or clinical studies, or off-label. To improve rehabilitation with cochlear implants (CI), one focus is the development of drug-releasing electrode carriers, e. g., for delivery of glucocorticosteroids, antiapoptotic substances, or neurotrophins to the inner ear. The performance of cochlear implants may thus be improved by protecting neuronal structures from insertion trauma, reducing fibrosis in the inner ear, and by stimulating growth of neuronal structures in the direction of the electrodes. Controlled drug release after extracochlear or intracochlear application in conjunction with a CI can also be achieved by use of a biocompatible, resorbable controlled-release drug-delivery system. Two case reports for intracochlear controlled release drug delivery in combination with cochlear implants are presented. In order to treat progressive reduction in speech discrimination and increased impedance, two cochlear implant patients successfully underwent intracochlear placement of a biocompatible, resorbable drug-delivery system for controlled release of dexamethasone. The drug levels reached in inner ear fluids after different types of local drug application strategies can be calculated using a computer model. The intracochlear drug concentrations calculated in this way were compared for different dexamethasone application strategies.
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Aminophylline restores glucocorticoid sensitivity in a guinea pig model of sudden sensorineural hearing loss induced by lipopolysaccharide. Sci Rep 2017; 7:2736. [PMID: 28578424 PMCID: PMC5457401 DOI: 10.1038/s41598-017-02956-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 04/21/2017] [Indexed: 11/08/2022] Open
Abstract
Glucocorticoids have been used to treat hearing loss and vestibular dysfunction for many years. However, some reports have indicated that a subset of patients with these disorders exhibit glucocorticoid insensitivity or resistance. A reduction in histone deacetylase 2 (HDAC2) activity and expression has been reported to play a critical role in glucocorticoid resistance. Here, we investigated the protective effects of aminophylline on HDAC2 expression and glucocorticoid sensitivity in lipopolysaccharide (LPS)-induced sudden sensorineural hearing loss in guinea pigs. We assessed hearing recovery in LPS-applied guinea pigs, which were either left untreated or were systemically treated with either dexamethasone, aminophylline, or a combination of the two. We utilized fluorescence microscopy and enzyme-linked immunosorbent assay to analyze the distribution patterns of HDAC2 and detect its levels in the cochlea. We used hematoxylin-eosin staining to examine cochlear histopathological changes. In the absence of treatment, significant hearing loss was detected in LPS-exposed animals. A synergistic effect was observed between aminophylline and dexamethasone in maintaining HDAC2 expression levels, preventing hearing loss in LPS-exposed animals and reducing cochlear damage. This study indicates that aminophylline can restore glucocorticoid sensitivity, which provides a new approach to treating patients with hearing disorders who are refractory to glucocorticoids.
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Ballivet de Régloix S, Crambert A, Maurin O, Lisan Q, Marty S, Pons Y. Blast injury of the ear by massive explosion: a review of 41 cases. J ROY ARMY MED CORPS 2017; 163:333-338. [DOI: 10.1136/jramc-2016-000733] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 12/27/2016] [Accepted: 01/11/2017] [Indexed: 11/03/2022]
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Bas E, Bohorquez J, Goncalves S, Perez E, Dinh CT, Garnham C, Hessler R, Eshraghi AA, Van De Water TR. Electrode array-eluted dexamethasone protects against electrode insertion trauma induced hearing and hair cell losses, damage to neural elements, increases in impedance and fibrosis: A dose response study. Hear Res 2016; 337:12-24. [DOI: 10.1016/j.heares.2016.02.003] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 12/30/2015] [Accepted: 02/11/2016] [Indexed: 12/13/2022]
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Sun C, Wang X, Chen D, Lin X, Yu D, Wu H. Dexamethasone loaded nanoparticles exert protective effects against Cisplatin-induced hearing loss by systemic administration. Neurosci Lett 2016; 619:142-8. [PMID: 26971701 DOI: 10.1016/j.neulet.2016.03.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 02/24/2016] [Accepted: 03/07/2016] [Indexed: 01/25/2023]
Abstract
Ototoxicity is one of the most important adverse effects of cisplatin chemotherapy. As a common treatment of acute sensorineural hearing loss, systemic administration of steroids was demonstrated ineffective against cisplatin-induced hearing loss (CIHL) in published studies. The current study aimed to evaluate the potential protective effect of dexamethasone (DEX) encapsulated in polyethyleneglycol-coated polylactic acid (PEG-PLA) nanoparticles (DEX-NPs) against cisplatin-induced hearing loss following systemic administration. DEX was fabricated into PEG-PLA nanoparticles using emulsion and evaporation technique as previously reported. DEX or DEX-NPs was administered intraperitoneally to guinea pigs 1h before cisplatin administration. Auditory brainstem response (ABR) threshold shifts were measured at four frequencies (4, 8, 16, and 24kHz) 1 day before and three days after cisplatin injection. Cochlear morphology was examined to evaluate inner ear injury induced by cisplatin exposure. A single dose of DEX-NPs 1h before cisplatin treatment resulted in a significant preservation of the functional and structural properties of the cochlea, which was equivalent to the effect of multidose (3 days) DEX injection. In contrast, no significant protective effect was observed by single dose injection of DEX. The results of histological examination of the cochleae were consistent with the functional measurements. In conclusion, a single dose DEX-NPs significantly attenuated cisplatin ototoxicity in guinea pigs after systemic administration at both histological and functional levels indicating the potential therapeutic benefits of these nanoparticles for enhancing the delivery of DEX in acute sensorineural hearing loss.
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Affiliation(s)
- Changling Sun
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose diseases, Shanghai 200092, China; Department of Otolaryngology-Head and Neck Surgery, Affiliated Hospital of Jiangnan University, The Fourth People's Hospital of Wuxi City, Wuxi 214062, China
| | - Xueling Wang
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose diseases, Shanghai 200092, China
| | - Dongye Chen
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose diseases, Shanghai 200092, China
| | - Xin Lin
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose diseases, Shanghai 200092, China
| | - Dehong Yu
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose diseases, Shanghai 200092, China.
| | - Hao Wu
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose diseases, Shanghai 200092, China.
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Mühlmeier G, Maier S, Maier M, Maier H. [Intratympanic injection therapy for therapy refractory acute hearing loss: A safe option for secondary treatment]. HNO 2015; 63:698-700, 702-6. [PMID: 26395186 DOI: 10.1007/s00106-015-0067-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND High-dose corticosteroids are currently recommended for idiopathic sudden sensorineural hearing loss (ISSNHL) treatment. Intratympanic injections (ITI) are of growing importance, especially in cases of therapy resistance. The selection of patients for this procedure in SSNHL has not been adequately examined so far. STUDY DESIGN A total of 77 patients with ISSNHL after ineffective systemic pretreatment underwent intratympanic administration of dexamethasone and hyaluronic acid. Improvement after treatment was determined by pure tone audiometry for both ears before and of the treated ear after ITI. RESULTS In this study 34 female and 43 male patients with mean age of 57 years showed a pre-ITI hearing loss of 35 dB in the lower frequencies and 69 dB in the higher frequencies. The mean hearing gain was 10 dB and the response rate was 62%. Absolute hearing gain revealed significant improvements at 500 Hz, 1 kHz and 2 kHz. Under inclusion of contralateral thresholds there were hardly any differences up to 4 kHz. In a detailed analysis of responders moderate improvements could be observed even in higher frequencies. Overall, no relevant adverse events occurred. CONCLUSION Treatment of ISSNHL resistant to systemic regimens by ITI of steroids provides an option that offers additional prospects of auditory improvement for affected patients. The presented results indicate that these modalities are also valid for patients with pancochlear ISSNHL.
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Affiliation(s)
- G Mühlmeier
- Hals-Nasen-Ohren-Heilkunde, Kopf- und Halschirurgie, Bundeswehrkrankenhaus Ulm, Oberer Eselsberg 40, 89081, Ulm, Deutschland.
| | - S Maier
- Hals-Nasen-Ohren-Heilkunde, Kopf- und Halschirurgie, Bundeswehrkrankenhaus Ulm, Oberer Eselsberg 40, 89081, Ulm, Deutschland
| | - M Maier
- Hals-Nasen-Ohren-Klinik, Universitätsklinikum Heidelberg, Heidelberg, Deutschland
| | - H Maier
- Hals-Nasen-Ohren-Heilkunde, Kopf- und Halschirurgie, Bundeswehrkrankenhaus Ulm, Oberer Eselsberg 40, 89081, Ulm, Deutschland
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Chen J, Zhao Y, Zhou X, Tan L, Ou Z, Yu Y, Wang Y. Methylprednisolone use during radiotherapy extenuates hearing loss in patients with nasopharyngeal carcinoma. Laryngoscope 2015; 126:100-3. [PMID: 26309227 DOI: 10.1002/lary.25527] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/30/2015] [Indexed: 11/08/2022]
Abstract
OBJECTIVES/HYPOTHESIS To investigate the hearing protective effects of methylprednisolone use during radiotherapy in patients with nasopharyngeal carcinoma. STUDY DESIGN Prospective, controlled clinical study. METHODS Fifty-three patients with nasopharyngeal carcinoma (106 ears). Twenty-five patients (50 ears) received radiotherapy with intravenous methylprednisolone for 14 days, and another 28 patients (56 ears) received radiotherapy alone. Pure tone audiometry, distortion product otoacoustic emission (DPOAE), and auditory brainstem responses (ABR) results were reviewed before and 1 year after radiotherapy. RESULT One year after radiotherapy, the air-and-bone conduction pure tone hearing thresholds increased, and the DPOAE levels decreased in the control group. There was no difference in the ABR wave I, III, and V latencies and the I to V interwave latencies before and 1 year after radiotherapy. The pure tone air conduction thresholds decreased, and the DPOAE levels increased in the treatment group compared with the control group. CONCLUSION Early sensorineural hearing loss after radiotherapy primarily affected the outer hair cells. The use of methylprednisolone during radiotherapy can extenuate early sensorineural hearing loss caused by irradiation.
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Affiliation(s)
- Junming Chen
- Department of Otolaryngology, The First People's Hospital of Foshan, Foshan, People's Republic of China
| | - Yuanxin Zhao
- Department of Otolaryngology, The First People's Hospital of Foshan, Foshan, People's Republic of China
| | | | - Lingmei Tan
- Department of Otolaryngology, The First People's Hospital of Foshan, Foshan, People's Republic of China
| | - Zeying Ou
- Department of Otolaryngology, The First People's Hospital of Foshan, Foshan, People's Republic of China
| | - Youjun Yu
- Department of Otolaryngology, The First People's Hospital of Foshan, Foshan, People's Republic of China
| | - Yuejian Wang
- Department of Otolaryngology, The First People's Hospital of Foshan, Foshan, People's Republic of China
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Svedbrant J, Bark R, Hultcrantz M, Hederstierna C. Hearing decline in menopausal women--a 10-year follow-up. Acta Otolaryngol 2015; 135:807-13. [PMID: 25891312 DOI: 10.3109/00016489.2015.1023354] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONCLUSIONS An unexpected rapid hearing decline remained after the 10-year follow up, similar to the hearing decline in 70-year-old women in reference materials. No clear changes concerning hearing in the peri- and postmenopausal period were noted. OBJECTIVE To assess whether hearing decline correlates with menopause and/or cortisol blood levels. METHODS A prospective individual longitudinal study of peri-menopausal women followed for 10 years was performed at baseline, and after 2, 7 and 10 years, respectively. With a starting age of around 51 years, 100 women remained in the study after 10 years. Pure-tone audiometry and cortisol blood testing were performed at all visits. RESULTS A continuous hearing decline, at all frequencies, was found during the follow-up time. The rate of decline during the menopausal period was higher than compared with reference materials for the same age group. The correlation with time for menopause is most apparent at 1 and 3 kHz where the hearing decline is more rapid after menopause than before. Serum cortisol levels did not correlate with rate of hearing decline.
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Affiliation(s)
- Johan Svedbrant
- Department of Clinical Sciences, Intervention and Technology, CLINTEC, Karolinska Institutet
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Eggermont JJ, Roberts LE. Tinnitus: animal models and findings in humans. Cell Tissue Res 2015; 361:311-36. [PMID: 25266340 PMCID: PMC4487353 DOI: 10.1007/s00441-014-1992-8] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 08/14/2014] [Indexed: 12/19/2022]
Abstract
Chronic tinnitus (ringing of the ears) is a medically untreatable condition that reduces quality of life for millions of individuals worldwide. Most cases are associated with hearing loss that may be detected by the audiogram or by more sensitive measures. Converging evidence from animal models and studies of human tinnitus sufferers indicates that, while cochlear damage is a trigger, most cases of tinnitus are not generated by irritative processes persisting in the cochlea but by changes that take place in central auditory pathways when auditory neurons lose their input from the ear. Forms of neural plasticity underlie these neural changes, which include increased spontaneous activity and neural gain in deafferented central auditory structures, increased synchronous activity in these structures, alterations in the tonotopic organization of auditory cortex, and changes in network behavior in nonauditory brain regions detected by functional imaging of individuals with tinnitus and corroborated by animal investigations. Research on the molecular mechanisms that underlie neural changes in tinnitus is in its infancy and represents a frontier for investigation.
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Affiliation(s)
- Jos J Eggermont
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, and Department of Psychology, University of Calgary, 2500 University Drive N.W, Calgary, AB, Canada,
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Vetter DE. Cellular signaling protective against noise-induced hearing loss – A role for novel intrinsic cochlear signaling involving corticotropin-releasing factor? Biochem Pharmacol 2015; 97:1-15. [PMID: 26074267 DOI: 10.1016/j.bcp.2015.06.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 06/08/2015] [Indexed: 12/11/2022]
Abstract
Hearing loss afflicts approximately 15% of the world's population, and crosses all socioeconomic boundaries. While great strides have been made in understanding the genetic components of syndromic and non-syndromic hearing loss, understanding of the mechanisms underlying noise-induced hearing loss (NIHL) have come much more slowly. NIHL is not simply a mechanism by which older individuals loose their hearing. Significantly, the incidence of NIHL is increasing, and is now involving ever younger populations. This may predict future increased occurrences of hearing loss. Current research has shown that even short-term exposures to loud sounds generating what was previously considered temporary hearing loss, actually produces an almost immediate and permanent loss of specific populations of auditory nerve fibers. Additionally, recurrent exposures to intense sound may hasten age-related hearing loss. While NIHL is a significant medical concern, to date, few compounds have delivered significant protection, arguing that new targets need to be identified. In this commentary, we will explore cellular signaling processes taking place in the cochlea believed to be involved in protection against hearing loss, and highlight new data suggestive of novel signaling not previously recognized as occurring in the cochlea, that is perhaps protective of hearing. This includes a recently described local hypothalamic-pituitary-adrenal axis (HPA)-like signaling system fully contained in the cochlea. This system may represent a local cellular stress-response system based on stress hormone release similar to the systemic HPA axis. Its discovery may hold hope for new drug therapies that can be delivered directly to the cochlea, circumventing systemic side effects.
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Affiliation(s)
- Douglas E Vetter
- University of Mississippi Medical Center, Department of Neurobiology and Anatomical Sciences, 2500 N. State St., Jackson, MS 39216, USA.
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Sun C, Wang X, Zheng Z, Chen D, Wang X, Shi F, Yu D, Wu H. A single dose of dexamethasone encapsulated in polyethylene glycol-coated polylactic acid nanoparticles attenuates cisplatin-induced hearing loss following round window membrane administration. Int J Nanomedicine 2015; 10:3567-79. [PMID: 25999718 PMCID: PMC4437605 DOI: 10.2147/ijn.s77912] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
This study aimed to investigate the sustained drug release properties and hearing protection effect of polyethylene glycol-coated polylactic acid (PEG-PLA) stealth nanoparticles loaded with dexamethasone (DEX). DEX was fabricated into PEG-PLA nanoparticles using an emulsion and evaporation technique, as previously reported. The DEX-loaded PEG-PLA nanoparticles (DEX-NPs) had a hydrodynamic diameter of 130±4.78 nm, and a zeta potential of −26.13±3.28 mV. The in vitro release of DEX from DEX-NPs lasted 24 days in phosphate buffered saline (pH 7.4), 5 days in artificial perilymph (pH 7.4), and 1 day in rat plasma. Coumarin 6-labeled NPs placed onto the round window membrane (RWM) of guinea pigs penetrated RWM quickly and accumulated to the organs of Corti, stria vascularis, and spiral ganglion cells after 1 hour of administration. The DEX-NPs locally applied onto the RWM of guinea pigs by a single-dose administration continuously released DEX in 48 hours, which was significantly longer than the free DEX that was cleared out within 12 hours after administration at the same dose. Further functional studies showed that locally administrated single-dose DEX-NPs effectively preserved outer hair cells in guinea pigs after cisplatin insult and thus significantly attenuated hearing loss at 4 kHz and 8 kHz frequencies when compared to the control of free DEX formulation. Histological analyses indicated that the administration of DEX-NPs did not induce local inflammatory responses. Therefore, prolonged delivery of DEX by PEG-PLA nanoparticles through local RWM diffusion (administration) significantly protected the hair cells and auditory function in guinea pigs from cisplatin toxicity, as determined at both histological and functional levels, suggesting the potential therapeutic benefits in clinical applications.
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Affiliation(s)
- Changling Sun
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, People's Republic of China ; Department of Otolaryngology-Head and Neck Surgery, Affiliated Hospital of Jiangnan University, The Fourth People's Hospital of Wuxi City, Wuxi, People's Republic of China
| | - Xueling Wang
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, People's Republic of China
| | - Zhaozhu Zheng
- National Engineering Laboratory for Modern Silk, Soochow University, Suzhou, People's Republic of China
| | - Dongye Chen
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, People's Republic of China
| | - Xiaoqin Wang
- National Engineering Laboratory for Modern Silk, Soochow University, Suzhou, People's Republic of China
| | - Fuxin Shi
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, People's Republic of China
| | - Dehong Yu
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, People's Republic of China
| | - Hao Wu
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, People's Republic of China
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Heinrich UR, Strieth S, Schmidtmann I, Stauber R, Helling K. Dexamethasone prevents hearing loss by restoring glucocorticoid receptor expression in the guinea pig cochlea. Laryngoscope 2015; 126:E29-34. [DOI: 10.1002/lary.25345] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/30/2015] [Indexed: 12/20/2022]
Affiliation(s)
- Ulf-Rüdiger Heinrich
- Department of Otorhinolaryngology, Head and Neck Surgery; University Medical Center of the Johannes Gutenberg-University; Mainz Germany
| | - Sebastian Strieth
- Department of Otorhinolaryngology, Head and Neck Surgery; University Medical Center of the Johannes Gutenberg-University; Mainz Germany
| | - Irene Schmidtmann
- Institute for Medical Statistics, Epidemiology and Informatics; University Medical Center of the Johannes Gutenberg-University; Mainz Germany
| | - Roland Stauber
- Department of Otorhinolaryngology, Head and Neck Surgery; University Medical Center of the Johannes Gutenberg-University; Mainz Germany
| | - Kai Helling
- Department of Otorhinolaryngology, Head and Neck Surgery; University Medical Center of the Johannes Gutenberg-University; Mainz Germany
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Martin-Sanz E, Esteban-Sanchez J, Rodrigañez-Riesco L, Sanz-Fernández R. Transitory effect on endolymphatic hydrops of the intratympanic steroids for Ménière's disease. Laryngoscope 2014; 125:1183-8. [PMID: 25429741 DOI: 10.1002/lary.25057] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 10/29/2014] [Accepted: 11/03/2014] [Indexed: 11/06/2022]
Abstract
OBJECTIVES/HYPOTHESIS This study aimed to evaluate the changes in electrocochleography (EcohG) measurements after intratympanic (IT) dexamethasone therapy and to correlate them with the long-term effects on the control of vertigo. STUDY DESIGN Prospective outcomes research. METHODS This study included 62 patients with unilateral Ménière's Disease (MD) refractory to medical therapy for at least 1 year. Each patient was treated with a fixed protocol of three consecutive weekly injections of a commercial 4 mg/mL dexamethasone preparation. The 1995 American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) criteria for reporting treatment outcomes for MD were used. Electrocochleography (EcohG) measurements were performed 1 month before and 1 and 12 months after IT steroid therapy. Caloric test and vestibular evoked myogenic potential (VEMPs) were performed before the IT treatment. The summating potential/action potential (SP/AP) ratio was measured before and after the IT treatment. A Kaplan-Meier analysis was used to evaluate the control of vertigo over a 2-year period. RESULTS Complete vertigo control (class A) was achieved in 26 patients (41.9%) at the 12-month follow-up and in 12 patients (19.3%) at the 24-month follow-up. A significant reduction (P < 0.01) in the SP/AP ratio after the IT steroid treatment was observed in the first-month determination, but no significant differences were found when the initial and 12-month determination were compared. CONCLUSIONS IT dexamethasone provides an alternative treatment for patients with Ménière's Disease. A transitory reduction of the endolymphatic hydrops is detected by the EcohG 1 month after treatment. The hydrops levels returned to their initial values in the 1-year EcohG follow-up. LEVEL OF EVIDENCE 2b.
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Smith AR, Kwon JH, Navarro M, Hurley LM. Acoustic trauma triggers upregulation of serotonin receptor genes. Hear Res 2014; 315:40-8. [PMID: 24997228 PMCID: PMC4140997 DOI: 10.1016/j.heares.2014.06.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 05/20/2014] [Accepted: 06/22/2014] [Indexed: 11/17/2022]
Abstract
Hearing loss induces plasticity in excitatory and inhibitory neurotransmitter systems in auditory brain regions. Excitatory-inhibitory balance is also influenced by a range of neuromodulatory regulatory systems, but less is known about the effects of auditory damage on these networks. In this work, we studied the effects of acoustic trauma on neuromodulatory plasticity in the auditory midbrain of CBA/J mice. Quantitative PCR was used to measure the expression of serotonergic and GABAergic receptor genes in the inferior colliculus (IC) of mice that were unmanipulated, sham controls with no hearing loss, and experimental individuals with hearing loss induced by exposure to a 116 dB, 10 kHz pure tone for 3 h. Acoustic trauma induced substantial hearing loss that was accompanied by selective upregulation of two serotonin receptor genes in the IC. The Htr1B receptor gene was upregulated tenfold following trauma relative to shams, while the Htr1A gene was upregulated threefold. In contrast, no plasticity in serotonin receptor gene expression was found in the hippocampus, a region also innervated by serotonergic projections. Analyses in the IC demonstrated that acoustic trauma also changed the coexpression of genes in relation to each other, leading to an overexpression of Htr1B compared to other genes. These data suggest that acoustic trauma induces serotonergic plasticity in the auditory system, and that this plasticity may involve comodulation of functionally-linked receptor genes.
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Affiliation(s)
- Adam R Smith
- Department of Biology, Indiana University, Bloomington, IN 47405, USA.
| | - Jae Hyun Kwon
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | - Marco Navarro
- Department of Biology, Indiana University, Bloomington, IN 47405, USA; Department of Biology, Saint Louis University, Saint Louis, MO 63103, USA
| | - Laura M Hurley
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
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Chen L, Dean C, Gandolfi M, Nahm E, Mattiace L, Kim AH. Dexamethasone's effect in the retrocochlear auditory centers of a noise-induced hearing loss mouse model. Otolaryngol Head Neck Surg 2014; 151:667-74. [PMID: 25113508 DOI: 10.1177/0194599814545771] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE Examine prophylactic effects of dexamethasone (Dex) in retrocochlear auditory centers in a noise-induced hearing loss (NIHL) mouse model. STUDY DESIGN Prospective animal study. SETTING Academic research center. SUBJECTS AND METHODS Thirty-two mice were divided into control, untreated, saline (2 and 10 µL), and Dex (2 and 10 µL) groups. Dex was applied intratympanically (IT) prior to 110 to 120 dB noise over 6 hours. Auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) were performed at 1 day, 1 week, 1 month, and 2 months. Retrocochlear neuronal cells were labeled with FluoroGold and counted. Hair cells of the organ of Corti were labeled with fluorescein isothiocyanate-conjugated phalloidin and counted. RESULTS Auditory brainstem response thresholds of untreated NIHL, 2 and 10 µL IT saline, and 2 and 10 µL IT Dex were 21.7 ± 2.9 dB, 20 ± 0 dB, 20 ± 5 dB, 18.3 ± 2.9 dB, and 18.3 ± 2.9 dB, respectively. At 1-day post NIHL, all groups demonstrated profound hearing loss. At 2 weeks, 2 and 10 µL Dex thresholds improved to 47.5 ± 3.5 dB and 48.8 ± 18.9 dB, respectively, whereas the untreated and saline groups remained unchanged. Mean cell counts in the cochlear nucleus (CN), superior olivary complex (SOC), and lateral lemniscus (LL) of control mice were 1483 ± 190, 2807 ± 67, and 112 ± 20, respectively. After acoustic trauma, the untreated, saline, and 2 µL Dex groups yielded decreased neuronal counts in the SOC. In contrast, the 10 µL Dex group had 1883 ± 186 (CN), 2774 ± 182 (SOC), and 166 ± 18 (LL). There was sporadic hair cell loss for all traumatized groups. CONCLUSION Our NIHL mouse model demonstrated dose-dependent Dex pretreatment otoprotection against NIHL with preservation of retrocochlear auditory neurons.
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Affiliation(s)
- Leon Chen
- Department of Otolaryngology-Head and Neck Surgery, New York Eye and Ear Infirmary, New York, New York, USA
| | - Clare Dean
- Department of Otolaryngology-Head and Neck Surgery, New York Eye and Ear Infirmary, New York, New York, USA
| | - Michele Gandolfi
- Department of Otolaryngology-Head and Neck Surgery, New York Eye and Ear Infirmary, New York, New York, USA
| | - Edmund Nahm
- Department of Otolaryngology-Head and Neck Surgery, New York Eye and Ear Infirmary, New York, New York, USA
| | - Linda Mattiace
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, New York, USA
| | - Ana H Kim
- Department of Otolaryngology-Head and Neck Surgery, New York Eye and Ear Infirmary, New York, New York, USA Department of Cell Biology and Anatomy, New York Medical College, Valhalla, New York, USA
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