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Hemachandran S, Hu N, Kane CJ, Green SH. Cyclic AMP signaling promotes regeneration of cochlear synapses after excitotoxic or noise trauma. Front Cell Neurosci 2024; 18:1363219. [PMID: 38694536 PMCID: PMC11061447 DOI: 10.3389/fncel.2024.1363219] [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: 12/30/2023] [Accepted: 03/27/2024] [Indexed: 05/04/2024] Open
Abstract
Introduction Cochlear afferent synapses connecting inner hair cells to spiral ganglion neurons are susceptible to excitotoxic trauma on exposure to loud sound, resulting in a noise-induced cochlear synaptopathy (NICS). Here we assessed the ability of cyclic AMP-dependent protein kinase (PKA) signaling to promote cochlear synapse regeneration, inferred from its ability to promote axon regeneration in axotomized CNS neurons, another system refractory to regeneration. Methods We mimicked NICS in vitro by applying a glutamate receptor agonist, kainic acid (KA) to organotypic cochlear explant cultures and experimentally manipulated cAMP signaling to determine whether PKA could promote synapse regeneration. We then delivered the cAMP phosphodiesterase inhibitor rolipram via implanted subcutaneous minipumps in noise-exposed CBA/CaJ mice to test the hypothesis that cAMP signaling could promote cochlear synapse regeneration in vivo. Results We showed that the application of the cell membrane-permeable cAMP agonist 8-cpt-cAMP or the cAMP phosphodiesterase inhibitor rolipram promotes significant regeneration of synapses in vitro within twelve hours after their destruction by KA. This is independent of neurotrophin-3, which also promotes synapse regeneration. Moreover, of the two independent signaling effectors activated by cAMP - the cAMP Exchange Protein Activated by cAMP and the cAMP-dependent protein kinase - it is the latter that mediates synapse regeneration. Finally, we showed that systemic delivery of rolipram promotes synapse regeneration in vivo following NICS. Discussion In vitro experiments show that cAMP signaling promotes synapse regeneration after excitotoxic destruction of cochlear synapses and does so via PKA signaling. The cAMP phosphodiesterase inhibitor rolipram promotes synapse regeneration in vivo in noise-exposed mice. Systemic administration of rolipram or similar compounds appears to provide a minimally invasive therapeutic approach to reversing synaptopathy post-noise.
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Affiliation(s)
| | | | | | - Steven H. Green
- Department of Biology, University of Iowa, Iowa City, IA, United States
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Yu C, He Y, Liu Q, Qian X, Gao X, Yang D, Yang Y, Wan G. Thyroid hormone controls the timing of cochlear ribbon synapse maturation. Biochem Biophys Res Commun 2024; 704:149704. [PMID: 38430700 DOI: 10.1016/j.bbrc.2024.149704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 01/25/2024] [Accepted: 02/20/2024] [Indexed: 03/05/2024]
Abstract
Ribbon synapses in the cochlear hair cells are subject to extensive pruning and maturation processes before hearing onset. Previous studies have highlighted the pivotal role of thyroid hormone (TH) in this developmental process, yet the detailed mechanisms are largely unknown. In this study, we found that the thyroid hormone receptor α (Thrα) is expressed in both sensory epithelium and spiral ganglion neurons in mice. Hypothyroidism, induced by Pax8 gene knockout, significantly delays the synaptic pruning during postnatal development in mice. Detailed spatiotemporal analysis of ribbon synapse distribution reveals that synaptic maturation involves not only ribbon pruning but also their migration, both of which are notably delayed in the cochlea of Pax8 knockout mice. Intriguingly, postnatal hyperthyroidism, induced by intraperitoneal injections of liothyronine sodium (T3), accelerates the pruning of ribbon synapses to the mature state without affecting the auditory functions. Our findings suggest that thyroid hormone does not play a deterministic role but rather controls the timing of cochlear ribbon synapse maturation.
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Affiliation(s)
- Chaorong Yu
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical School, Nanjing University, Nanjing, 210061, China; MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of China, Nanjing University, Nanjing, 210061, China
| | - Yihan He
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical School, Nanjing University, Nanjing, 210061, China; MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of China, Nanjing University, Nanjing, 210061, China
| | - Qing Liu
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical School, Nanjing University, Nanjing, 210061, China; MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of China, Nanjing University, Nanjing, 210061, China; Research Institute of Otolaryngology, No. 321 Zhongshan Road, Nanjing, 210061, China
| | - Xiaoyun Qian
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical School, Nanjing University, Nanjing, 210061, China; Research Institute of Otolaryngology, No. 321 Zhongshan Road, Nanjing, 210061, China
| | - Xia Gao
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical School, Nanjing University, Nanjing, 210061, China; Research Institute of Otolaryngology, No. 321 Zhongshan Road, Nanjing, 210061, China
| | - Deye Yang
- Department of Cardiology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang, 310000, China.
| | - Ye Yang
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical School, Nanjing University, Nanjing, 210061, China; Research Institute of Otolaryngology, No. 321 Zhongshan Road, Nanjing, 210061, China.
| | - Guoqiang Wan
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical School, Nanjing University, Nanjing, 210061, China; MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of China, Nanjing University, Nanjing, 210061, China; Research Institute of Otolaryngology, No. 321 Zhongshan Road, Nanjing, 210061, China.
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3
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Wu PZ, Liberman LD, Liberman MC. Noise-induced synaptic loss and its post-exposure recovery in CBA/CaJ vs. C57BL/6J mice. Hear Res 2024; 445:108996. [PMID: 38547565 PMCID: PMC11024800 DOI: 10.1016/j.heares.2024.108996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/11/2024] [Accepted: 03/22/2024] [Indexed: 04/07/2024]
Abstract
Acute noise-induced loss of synapses between inner hair cells (IHCs) and auditory nerve fibers (ANFs) has been documented in several strains of mice, but the extent of post-exposure recovery reportedly varies dramatically. If such inter-strain heterogeneity is real, it could be exploited to probe molecular pathways mediating neural remodeling in the adult cochlea. Here, we compared synaptopathy repair in CBA/CaJ vs. C57BL/6J, which are at opposite ends of the reported recovery spectrum. We evaluated C57BL/6J mice 0 h, 24 h, 2 wks or 8 wks after exposure for 2 h to octave-band noise (8-16 kHz) at either 90, 94 or 98 dB SPL, to compare with analogous post-exposure results in CBA/CaJ at 98 or 101 dB. We counted pre- and post-synaptic puncta in immunostained cochleas, using machine learning to classify paired (GluA2 and CtBP2) vs. orphan (CtBP2 only) puncta, and batch-processing to quantify immunostaining intensity. At 98 dB, both strains show ongoing loss of ribbons and synapses between 0 and 24 h, followed by partial recovery, however the extent and degree of these changes were greater in C57BL/6J. Much of the synaptic recovery is due to transient reduction in GluA2 intensity in synaptopathic regions. In contrast, CtBP2 intensity showed only transient increases (at 2 wks). Neurofilament staining revealed transient extension of ANF terminals in C57BL/6J, but not in CBA/CaJ, peaking at 24 h and reverting by 2 wks. Thus, although interstrain differences in synapse recovery are dominated by reversible changes in GluA2 receptor levels, the neurite extension seen in C57BL/6J suggests a qualitative difference in regenerative capacity.
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Affiliation(s)
- Pei-Zhe Wu
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, MA 02114, USA; Department of Otolaryngology, Harvard Medical School, Boston, MA 02115, USA
| | - Leslie D Liberman
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, MA 02114, USA
| | - M Charles Liberman
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, MA 02114, USA; Department of Otolaryngology, Harvard Medical School, Boston, MA 02115, USA.
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Cassinotti LR, Ji L, Yuk MC, Desai AS, Cass ND, Amir ZA, Corfas G. Hidden hearing loss in hereditary demyelinating neuropathies: insights from Charcot-Marie-Tooth mouse models. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.14.571732. [PMID: 38168255 PMCID: PMC10760174 DOI: 10.1101/2023.12.14.571732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Hidden hearing loss (HHL) is a recently described auditory neuropathy characterized by normal audiometric thresholds but reduced sound-evoked potentials. It has been proposed that HHL contributes to hearing difficulty in noisy environments in people with normal audiometric thresholds, a widespread complaint. While most studies on HHL pathogenesis have focused on inner hair cell (IHC) synaptopathy, recent research suggests that transient auditory nerve (AN) demyelination may also cause HHL. To test the impact of myelinopathy in a clinically relevant model, we studied a mouse model of Charcot-Marie-Tooth type 1A (CMT1A), the most prevalent hereditary peripheral neuropathy in humans. CMT1A mice exhibit the functional hallmarks of HHL, together with disorganization of AN heminodes near the IHCs with minor loss of AN fibers. Our results support the hypothesis that mild disruptions of AN myelination can cause HHL, and that heminodal defects contribute to the alterations in action potential amplitudes and latencies seen in these models. Also, these findings suggest that patients with CMT1A or other mild peripheral neuropathies are likely to suffer from HHL. Furthermore, these results suggest that studies of hearing in CMT1A patients might help develop robust clinical tests for HHL, which are currently lacking.
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Saidia AR, François F, Casas F, Mechaly I, Venteo S, Veechi JT, Ruel J, Puel JL, Wang J. Oxidative Stress Plays an Important Role in Glutamatergic Excitotoxicity-Induced Cochlear Synaptopathy: Implication for Therapeutic Molecules Screening. Antioxidants (Basel) 2024; 13:149. [PMID: 38397748 PMCID: PMC10886292 DOI: 10.3390/antiox13020149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 01/12/2024] [Accepted: 01/20/2024] [Indexed: 02/25/2024] Open
Abstract
The disruption of the synaptic connection between the sensory inner hair cells (IHCs) and the auditory nerve fiber terminals of the type I spiral ganglion neurons (SGN) has been observed early in several auditory pathologies (e.g., noise-induced or ototoxic drug-induced or age-related hearing loss). It has been suggested that glutamate excitotoxicity may be an inciting element in the degenerative cascade observed in these pathological cochlear conditions. Moreover, oxidative damage induced by free hydroxyl radicals and nitric oxide may dramatically enhance cochlear damage induced by glutamate excitotoxicity. To investigate the underlying molecular mechanisms involved in cochlear excitotoxicity, we examined the molecular basis responsible for kainic acid (KA, a full agonist of AMPA/KA-preferring glutamate receptors)-induced IHC synapse loss and degeneration of the terminals of the type I spiral ganglion afferent neurons using a cochlear explant culture from P3 mouse pups. Our results demonstrated that disruption of the synaptic connection between IHCs and SGNs induced increased levels of oxidative stress, as well as altered both mitochondrial function and neurotrophin signaling pathways. Additionally, the application of exogenous antioxidants and neurotrophins (NT3, BDNF, and small molecule TrkB agonists) clearly increases synaptogenesis. These results suggest that understanding the molecular pathways involved in cochlear excitotoxicity is of crucial importance for the future clinical trials of drug interventions for auditory synaptopathies.
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Affiliation(s)
- Anissa Rym Saidia
- Institute for Neurosciences of Montpellier (INM), INSERM U1298, University Montpellier, 34295 Montpellier, France; (F.F.); (I.M.); (S.V.); (J.T.V.); (J.-L.P.)
| | - Florence François
- Institute for Neurosciences of Montpellier (INM), INSERM U1298, University Montpellier, 34295 Montpellier, France; (F.F.); (I.M.); (S.V.); (J.T.V.); (J.-L.P.)
| | - François Casas
- INRA, UMR 866 Dynamique Musculaire et Métabolisme, 34060 Montpellier, France;
| | - Ilana Mechaly
- Institute for Neurosciences of Montpellier (INM), INSERM U1298, University Montpellier, 34295 Montpellier, France; (F.F.); (I.M.); (S.V.); (J.T.V.); (J.-L.P.)
| | - Stéphanie Venteo
- Institute for Neurosciences of Montpellier (INM), INSERM U1298, University Montpellier, 34295 Montpellier, France; (F.F.); (I.M.); (S.V.); (J.T.V.); (J.-L.P.)
| | - Joseph T. Veechi
- Institute for Neurosciences of Montpellier (INM), INSERM U1298, University Montpellier, 34295 Montpellier, France; (F.F.); (I.M.); (S.V.); (J.T.V.); (J.-L.P.)
| | - Jérôme Ruel
- Centre de Recherche en CardioVasculaire et Nutrition, Aix-Marseille Université-INSERM, 1263-INRAE 1260, 13385 Marseille, France;
| | - Jean-Luc Puel
- Institute for Neurosciences of Montpellier (INM), INSERM U1298, University Montpellier, 34295 Montpellier, France; (F.F.); (I.M.); (S.V.); (J.T.V.); (J.-L.P.)
| | - Jing Wang
- Institute for Neurosciences of Montpellier (INM), INSERM U1298, University Montpellier, 34295 Montpellier, France; (F.F.); (I.M.); (S.V.); (J.T.V.); (J.-L.P.)
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Li L, Shen T, Liu S, Qi J, Zhao Y. Advancements and future prospects of adeno-associated virus-mediated gene therapy for sensorineural hearing loss. Front Neurosci 2024; 18:1272786. [PMID: 38327848 PMCID: PMC10847333 DOI: 10.3389/fnins.2024.1272786] [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: 08/04/2023] [Accepted: 01/12/2024] [Indexed: 02/09/2024] Open
Abstract
Sensorineural hearing loss (SNHL), a highly prevalent sensory impairment, results from a multifaceted interaction of genetic and environmental factors. As we continually gain insights into the molecular basis of auditory development and the growing compendium of deafness genes identified, research on gene therapy for SNHL has significantly deepened. Adeno-associated virus (AAV), considered a relatively secure vector for gene therapy in clinical trials, can deliver various transgenes based on gene therapy strategies such as gene replacement, gene silencing, gene editing, or gene addition to alleviate diverse types of SNHL. This review delved into the preclinical advances in AAV-based gene therapy for SNHL, spanning hereditary and acquired types. Particular focus is placed on the dual-AAV construction method and its application, the vector delivery route of mouse inner ear models (local, systemic, fetal, and cerebrospinal fluid administration), and the significant considerations in transforming from AAV-based animal model inner ear gene therapy to clinical implementation.
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Affiliation(s)
- Linke Li
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Tian Shen
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Shixi Liu
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Jieyu Qi
- State Key Laboratory of Bioelectronics, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Yu Zhao
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
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Yang ZJ, Zhao CL, Liang WQ, Chen ZR, Du ZD, Gong SS. ROS-induced oxidative stress and mitochondrial dysfunction: a possible mechanism responsible for noise-induced ribbon synaptic damage. Am J Transl Res 2024; 16:272-284. [PMID: 38322575 PMCID: PMC10839402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 01/05/2024] [Indexed: 02/08/2024]
Abstract
Evidence suggests that damage to the ribbon synapses (RS) may be the main cause of auditory dysfunction in noise-induced hearing loss (NIHL). Oxidative stress is implicated in the pathophysiology of synaptic damage. However, the relationship between oxidative stress and RS damage in NIHL remains unclear. To investigate the hypothesis that noise-induced oxidative stress is a key factor in synaptic damage within the inner ear, we conducted a study using mice subjected to single or repeated noise exposure (NE). We assessed auditory function using auditory brainstem response (ABR) test and examined cochlear morphology by immunofluorescence staining. The results showed that mice that experienced a single NE exhibited a threshold shift and recovered within two weeks. The ABR wave I latencies were prolonged, and the amplitudes decreased, suggesting RS dysfunction. These changes were also demonstrated by the loss of RS as evidenced by immunofluorescence staining. However, we observed threshold shifts that did not return to baseline levels following secondary NE. Additionally, ABR wave I latencies and amplitudes exhibited notable changes. Immunofluorescence staining indicated not only severe damage to RS but also loss of outer hair cells. We also noted decreased T-AOC, ATP, and mitochondrial membrane potential levels, alongside increased hydrogen peroxide concentrations post-NE. Furthermore, the expression levels of 4-HNE and 8-OHdG in the cochlea were notably elevated. Collectively, our findings suggest that the production of reactive oxygen species leads to oxidative damage in the cochlea. This mitochondrial dysfunction consequently contributes to the loss of RS, precipitating an early onset of NIHL.
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Affiliation(s)
- Zi-Jing Yang
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical UniversityBeijing 100050, China
- Clinical Center for Hearing Loss, Capital Medical UniversityBeijing 100050, China
| | - Chun-Li Zhao
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical UniversityBeijing 100050, China
- Clinical Center for Hearing Loss, Capital Medical UniversityBeijing 100050, China
| | - Wen-Qi Liang
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical UniversityBeijing 100050, China
- Clinical Center for Hearing Loss, Capital Medical UniversityBeijing 100050, China
| | - Zhong-Rui Chen
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical UniversityBeijing 100050, China
- Clinical Center for Hearing Loss, Capital Medical UniversityBeijing 100050, China
| | - Zheng-De Du
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical UniversityBeijing 100050, China
- Clinical Center for Hearing Loss, Capital Medical UniversityBeijing 100050, China
| | - Shu-Sheng Gong
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical UniversityBeijing 100050, China
- Clinical Center for Hearing Loss, Capital Medical UniversityBeijing 100050, China
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Pressé MT, Malgrange B, Delacroix L. The cochlear matrisome: Importance in hearing and deafness. Matrix Biol 2024; 125:40-58. [PMID: 38070832 DOI: 10.1016/j.matbio.2023.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 11/20/2023] [Accepted: 12/06/2023] [Indexed: 02/12/2024]
Abstract
The extracellular matrix (ECM) consists in a complex meshwork of collagens, glycoproteins, and proteoglycans, which serves a scaffolding function and provides viscoelastic properties to the tissues. ECM acts as a biomechanical support, and actively participates in cell signaling to induce tissular changes in response to environmental forces and soluble cues. Given the remarkable complexity of the inner ear architecture, its exquisite structure-function relationship, and the importance of vibration-induced stimulation of its sensory cells, ECM is instrumental to hearing. Many factors of the matrisome are involved in cochlea development, function and maintenance, as evidenced by the variety of ECM proteins associated with hereditary deafness. This review describes the structural and functional ECM components in the auditory organ and how they are modulated over time and following injury.
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Affiliation(s)
- Mary T Pressé
- Developmental Neurobiology Unit, GIGA-Neurosciences, University of Liège, 15 avenue Hippocrate - CHU - B36 (1st floor), Liège B-4000, Belgium
| | - Brigitte Malgrange
- Developmental Neurobiology Unit, GIGA-Neurosciences, University of Liège, 15 avenue Hippocrate - CHU - B36 (1st floor), Liège B-4000, Belgium
| | - Laurence Delacroix
- Developmental Neurobiology Unit, GIGA-Neurosciences, University of Liège, 15 avenue Hippocrate - CHU - B36 (1st floor), Liège B-4000, Belgium.
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Vincent PF, Young ED, Edge AS, Glowatzki E. Auditory Hair Cells and Spiral Ganglion Neurons Regenerate Synapses with Refined Release Properties In Vitro. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.05.561095. [PMID: 38076928 PMCID: PMC10705289 DOI: 10.1101/2023.10.05.561095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Ribbon synapses between inner hair cells (IHCs) and type I spiral ganglion neurons (SGNs) in the inner ear are damaged by noise trauma and with aging, causing 'synaptopathy 'and hearing loss. Co-cultures of neonatal denervated organs of Corti and newly introduced SGNs have been developed to find strategies for improving IHC synapse regeneration, but evidence of the physiological normality of regenerated synapses is missing. This study utilizes IHC optogenetic stimulation and SGN recordings, showing that newly formed IHC synapses are indeed functional, exhibiting glutamatergic excitatory postsynaptic currents. When older organs of Corti were plated, synaptic activity probed by deconvolution, showed more mature release properties, closer to the highly specialized mode of IHC synaptic transmission that is crucial for coding the sound signal. This newly developed functional assessment of regenerated IHC synapses provides a powerful tool for testing approaches to improve synapse regeneration.
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Affiliation(s)
- Philippe F.Y. Vincent
- The Center for Hearing and Balance, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Otolaryngology Head and Neck Surgery, The Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Eric D. Young
- The Center for Hearing and Balance, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Otolaryngology Head and Neck Surgery, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Neuroscience, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Biomedical Engineering, The Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Albert S.B. Edge
- Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, USA
- Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, Massachusetts, USA
- Harvard Stem Cell Institute, Cambridge, Massachusetts, USA
| | - Elisabeth Glowatzki
- The Center for Hearing and Balance, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Otolaryngology Head and Neck Surgery, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Neuroscience, The Johns Hopkins School of Medicine, Baltimore, Maryland
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Vasilkov V, Caswell-Midwinter B, Zhao Y, de Gruttola V, Jung DH, Liberman MC, Maison SF. Evidence of cochlear neural degeneration in normal-hearing subjects with tinnitus. Sci Rep 2023; 13:19870. [PMID: 38036538 PMCID: PMC10689483 DOI: 10.1038/s41598-023-46741-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 11/04/2023] [Indexed: 12/02/2023] Open
Abstract
Tinnitus, reduced sound-level tolerance, and difficulties hearing in noisy environments are the most common complaints associated with sensorineural hearing loss in adult populations. This study aims to clarify if cochlear neural degeneration estimated in a large pool of participants with normal audiograms is associated with self-report of tinnitus using a test battery probing the different stages of the auditory processing from hair cell responses to the auditory reflexes of the brainstem. Self-report of chronic tinnitus was significantly associated with (1) reduced cochlear nerve responses, (2) weaker middle-ear muscle reflexes, (3) stronger medial olivocochlear efferent reflexes and (4) hyperactivity in the central auditory pathways. These results support the model of tinnitus generation whereby decreased neural activity from a damaged cochlea can elicit hyperactivity from decreased inhibition in the central nervous system.
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Affiliation(s)
- Viacheslav Vasilkov
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02114, USA
| | - Benjamin Caswell-Midwinter
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02114, USA
| | - Yan Zhao
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA
| | - Victor de Gruttola
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, 02114, USA
| | - David H Jung
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02114, USA
| | - M Charles Liberman
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02114, USA
| | - Stéphane F Maison
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA.
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02114, USA.
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Zhu G, Huang Y, Zhang L, Yan K, Qiu C, He Y, Liu Q, Zhu C, Morín M, Moreno‐Pelayo MÁ, Zhu M, Cao X, Zhou H, Qian X, Xu Z, Chen J, Gao X, Wan G. Cingulin regulates hair cell cuticular plate morphology and is required for hearing in human and mouse. EMBO Mol Med 2023; 15:e17611. [PMID: 37691516 PMCID: PMC10630877 DOI: 10.15252/emmm.202317611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 08/17/2023] [Accepted: 08/22/2023] [Indexed: 09/12/2023] Open
Abstract
Cingulin (CGN) is a cytoskeleton-associated protein localized at the apical junctions of epithelial cells. CGN interacts with major cytoskeletal filaments and regulates RhoA activity. However, physiological roles of CGN in development and human diseases are currently unknown. Here, we report a multi-generation family presenting with autosomal dominant non-syndromic hearing loss (ADNSHL) that co-segregates with a CGN heterozygous truncating variant, c.3330delG (p.Leu1110Leufs*17). CGN is normally expressed at the apical cell junctions of the organ of Corti, with enriched localization at hair cell cuticular plates and circumferential belts. In mice, the putative disease-causing mutation results in reduced expression and abnormal subcellular localization of the CGN protein, abolishes its actin polymerization activity, and impairs the normal morphology of hair cell cuticular plates and hair bundles. Hair cell-specific Cgn knockout leads to high-frequency hearing loss. Importantly, Cgn mutation knockin mice display noise-sensitive, progressive hearing loss and outer hair cell degeneration. In summary, we identify CGN c.3330delG as a pathogenic variant for ADNSHL and reveal essential roles of CGN in the maintenance of cochlear hair cell structures and auditory function.
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Affiliation(s)
- Guang‐Jie Zhu
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of ChinaNanjing UniversityNanjingChina
- Research Institute of OtolaryngologyNanjingChina
| | - Yuhang Huang
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of ChinaNanjing UniversityNanjingChina
| | - Linqing Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of ChinaNanjing UniversityNanjingChina
| | - Keji Yan
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology and Key Laboratory for Experimental Teratology of the Ministry of Education, School of Life SciencesShandong UniversityQingdaoChina
| | - Cui Qiu
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of ChinaNanjing UniversityNanjingChina
| | - Yihan He
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of ChinaNanjing UniversityNanjingChina
| | - Qing Liu
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of ChinaNanjing UniversityNanjingChina
- Research Institute of OtolaryngologyNanjingChina
| | - Chengwen Zhu
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of ChinaNanjing UniversityNanjingChina
- Research Institute of OtolaryngologyNanjingChina
| | - Matías Morín
- Servicio de GenéticaHospital Universitario Ramón y Cajal, IRYCISMadridSpain
- Centro de Investigación Biomédica en Red de Enfermedades RarasInstituto de Salud Carlos III (CB06/07/0048; CIBERER‐ISCIII)MadridSpain
| | - Miguel Ángel Moreno‐Pelayo
- Servicio de GenéticaHospital Universitario Ramón y Cajal, IRYCISMadridSpain
- Centro de Investigación Biomédica en Red de Enfermedades RarasInstituto de Salud Carlos III (CB06/07/0048; CIBERER‐ISCIII)MadridSpain
| | - Min‐Sheng Zhu
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of ChinaNanjing UniversityNanjingChina
- Research Institute of OtolaryngologyNanjingChina
| | - Xin Cao
- Department of Medical Genetics, School of Basic Medical ScienceNanjing Medical UniversityNanjingChina
| | - Han Zhou
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- Research Institute of OtolaryngologyNanjingChina
| | - Xiaoyun Qian
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- Research Institute of OtolaryngologyNanjingChina
| | - Zhigang Xu
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology and Key Laboratory for Experimental Teratology of the Ministry of Education, School of Life SciencesShandong UniversityQingdaoChina
| | - Jie Chen
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- Research Institute of OtolaryngologyNanjingChina
| | - Xia Gao
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- Research Institute of OtolaryngologyNanjingChina
| | - Guoqiang Wan
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical SchoolNanjing UniversityNanjingChina
- MOE Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, National Resource Center for Mutant Mice of ChinaNanjing UniversityNanjingChina
- Research Institute of OtolaryngologyNanjingChina
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12
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Gross J, Knipper M, Mazurek B. Candidate Key Proteins in Tinnitus: A Bioinformatic Study of Synaptic Transmission in Spiral Ganglion Neurons. Cell Mol Neurobiol 2023; 43:4189-4207. [PMID: 37736859 PMCID: PMC10661836 DOI: 10.1007/s10571-023-01405-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Accepted: 08/24/2023] [Indexed: 09/23/2023]
Abstract
To study key proteins associated with changes in synaptic transmission in the spiral ganglion in tinnitus, we build three gene lists from the GeneCard database: 1. Perception of sound (PoS), 2. Acoustic stimulation (AcouStim), and 3. Tinnitus (Tin). Enrichment analysis by the DAVID database resulted in similar Gene Ontology (GO) terms for cellular components in all gene lists, reflecting synaptic structures known to be involved in auditory processing. The STRING protein-protein interaction (PPI) network and the Cytoscape data analyzer were used to identify the top two high-degree proteins (HDPs) and their high-score interaction proteins (HSIPs) identified by the combined score (CS) of the corresponding edges. The top two protein pairs (key proteins) for the PoS are BDNF-GDNF and OTOF-CACNA1D and for the AcouStim process BDNF-NTRK2 and TH-CALB1. The Tin process showed BDNF and NGF as HDPs, with high-score interactions with NTRK1 and NGFR at a comparable level. Compared to the PoS and AcouStim process, the number of HSIPs of key proteins (CS > 90. percentile) increases strongly in Tin. In the PoS and AcouStim networks, BDNF receptor signaling is the dominant pathway, and in the Tin network, the NGF-signaling pathway is of similar importance. Key proteins and their HSIPs are good indicators of biological processes and of signaling pathways characteristic for the normal hearing on the one hand and tinnitus on the other.
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Affiliation(s)
- Johann Gross
- Tinnitus Center, Charité-Universitätsmedizin Berlin, Berlin, Germany.
- Leibniz Society of Science Berlin, Berlin, Germany.
| | - Marlies Knipper
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
- Leibniz Society of Science Berlin, Berlin, Germany
| | - Birgit Mazurek
- Tinnitus Center, Charité-Universitätsmedizin Berlin, Berlin, Germany
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Lai R, Fang Q, Wu F, Pan S, Haque K, Sha SH. Prevention of noise-induced hearing loss by calpain inhibitor MDL-28170 is associated with upregulation of PI3K/Akt survival signaling pathway. Front Cell Neurosci 2023; 17:1199656. [PMID: 37484825 PMCID: PMC10359991 DOI: 10.3389/fncel.2023.1199656] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 06/14/2023] [Indexed: 07/25/2023] Open
Abstract
Introduction Noise-induced calcium overload in sensory hair cells has been well documented as an early step in the pathogenesis of noise-induced hearing loss (NIHL). Alterations in cellular calcium homeostasis mediate a series of cellular events, including activation of calcium-dependent protein kinases and phosphatases. Using cell-membrane- and blood-brain-barrier-permeable calpain-1 (μ-calpain) and calpain-2 (m-calpain) inhibitor MDL-28170, we tested the involvement of calpains, a family of calcium-dependent cysteine proteases, and the potential of MDL-28170 in preventing NIHL. Methods CBA/J mice at the age of 12 weeks were exposed to broadband noise with a frequency spectrum from 2-20 kHz for 2 h at 101 dB sound pressure level to induce permanent hearing loss as measured by auditory brainstem response and distortion product otoacoustic emissions. Morphological damage was assessed by quantification of remaining sensory hair cells and inner hair cell synapses 2 weeks after the exposure. Results MDL-28170 treatment by intraperitoneal injection significantly attenuated noise-induced functional deficits and cochlear pathologies. MDL-28170 treatment also prevented noise-induced cleavage of alpha-fodrin, a substrate for calpain-1. Furthermore, MDL-28170 treatment prevented reduction of PI3K/Akt signaling after exposure to noise and upregulated p85α and p-Akt (S473) in outer hair cells. Discussion These results indicate that noise-induced calpain activation negatively regulates PI3K/Akt downstream signaling, and that prevention of NIHL by treatment with MDL-28170 is associated with upregulation of PI3K/Akt survival signaling pathways.
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Affiliation(s)
- Ruosha Lai
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
- Department of Otolaryngology, Head and Neck Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Qiaojun Fang
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Fan Wu
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Song Pan
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Khujista Haque
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Su-Hua Sha
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
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14
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Kempfle JS, Jung DH. Experimental drugs for the prevention or treatment of sensorineural hearing loss. Expert Opin Investig Drugs 2023; 32:643-654. [PMID: 37598357 DOI: 10.1080/13543784.2023.2242253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 07/26/2023] [Indexed: 08/22/2023]
Abstract
INTRODUCTION Sensorineural hearing loss results in irreversible loss of inner ear hair cells and spiral ganglion neurons. Reduced sound detection and speech discrimination can span all ages, and sensorineural hearing rehabilitation is limited to amplification with hearing aids or cochlear implants. Recent insights into experimental drug treatments for inner ear regeneration and otoprotection have paved the way for clinical trials in order to restore a more physiological hearing experience. Paired with the development of innovative minimally invasive approaches for drug delivery to the inner ear, new, emerging treatments for hearing protection and restoration are within reach. AREAS COVERED This expert opinion provides an overview of the latest experimental drug therapies to protect from and to restore sensorineural hearing loss. EXPERT OPINION The degree and type of cellular damage to the cochlea, the responsiveness of remaining, endogenous cells to regenerative treatments, and the duration of drug availability within cochlear fluids will determine the success of hearing protection or restoration.
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Affiliation(s)
- Judith S Kempfle
- Department of Otolaryngology, Massachusetts Eye and Ear, Boston, MA, USA
- Department of Otolaryngology, Head & Neck Surgery, Harvard Medical School, Boston, MA, USA
- Department of Otolaryngology, UMass Memorial Medical Center, Worcester, MA, USA
- Department of Otolaryngology, Head & Neck Surgery, University of Massachusetts Medical School, Worcester, MA, USA
| | - David H Jung
- Department of Otolaryngology, Massachusetts Eye and Ear, Boston, MA, USA
- Department of Otolaryngology, Head & Neck Surgery, Harvard Medical School, Boston, MA, USA
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15
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Xu K, Xu B, Gu J, Wang X, Yu D, Chen Y. Intrinsic mechanism and pharmacologic treatments of noise-induced hearing loss. Theranostics 2023; 13:3524-3549. [PMID: 37441605 PMCID: PMC10334830 DOI: 10.7150/thno.83383] [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: 02/09/2023] [Accepted: 06/12/2023] [Indexed: 07/15/2023] Open
Abstract
Noise accounts for one-third of hearing loss worldwide. Regretfully, noise-induced hearing loss (NIHL) is deemed to be irreversible due to the elusive pathogenic mechanisms that have not been fully elucidated. The complex interaction between genetic and environmental factors, which influences numerous downstream molecular and cellular events, contributes to the NIHL. In clinical settings, there are no effective therapeutic drugs other than steroids, which are the only treatment option for patients with NIHL. Therefore, the need for treatment of NIHL that is currently unmet, along with recent progress in our understanding of the underlying regulatory mechanisms, has led to a lot of new literatures focusing on this therapeutic field. The emergence of novel technologies that modify local drug delivery to the inner ear has led to the development of promising therapeutic approaches, which are currently under clinical investigation. In this comprehensive review, we focus on outlining and analyzing the basics and potential therapeutics of NIHL, as well as the application of biomaterials and nanomedicines in inner ear drug delivery. The objective of this review is to provide an incentive for NIHL's fundamental research and future clinical translation.
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Affiliation(s)
- Ke Xu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Ear Institute, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Baoying Xu
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, China
| | - Jiayi Gu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Ear Institute, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Xueling Wang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Ear Institute, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Dehong Yu
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, China
| | - Yu Chen
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, China
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16
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Uribe PM, Hudson AM, Lockard G, Jiang M, Harding J, Steyger PS, Coffin AB. Hepatocyte growth factor mimetic confers protection from aminoglycoside-induced hair cell death in vitro. Hear Res 2023; 434:108786. [PMID: 37192594 DOI: 10.1016/j.heares.2023.108786] [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: 08/09/2022] [Revised: 04/18/2023] [Accepted: 05/05/2023] [Indexed: 05/18/2023]
Abstract
Loss of sensory hair cells from exposure to certain licit drugs, such as aminoglycoside antibiotics, can result in permanent hearing damage. Exogenous application of the neurotrophic molecule hepatocyte growth factor (HGF) promotes neuronal cell survival in a variety of contexts, including protecting hair cells from aminoglycoside ototoxicity. HGF itself is not an ideal therapeutic due to a short half-life and limited blood-brain barrier permeability. MM-201 is a chemically stable, blood-brain barrier permeable, synthetic HGF mimetic that serves as a functional ligand to activate the HGF receptor and its downstream signaling cascade. We previously demonstrated that MM-201 robustly protects zebrafish lateral line hair cells from aminoglycoside ototoxicity. Here, we examined the ability of MM-201 to protect mammalian sensory hair cells from aminoglycoside damage to further evaluate MM-201's clinical potential. We found that MM-201 exhibited dose-dependent protection from neomycin and gentamicin ototoxicity in mature mouse utricular explants. MM-201's protection was reduced following inhibition of mTOR, a downstream target of HGF receptor activation, implicating the activation of endogenous intracellular substrates by MM-201 as critical for the observed protection. We then asked if MM-201 altered the bactericidal properties of aminoglycosides. Using either plate or liquid growth assays we found that MM-201 did not alter the bactericidal efficacy of aminoglycoside antibiotics at therapeutically relevant concentrations. We therefore assessed the protective capacity of MM-201 in an in vivo mouse model of kanamycin ototoxicity. In contrast to our in vitro data, MM-201 did not attenuate kanamycin ototoxicity in vivo. Further, we found that MM-201 was ototoxic to mice across the dose range tested here. These data suggest species- and tissue-specific differences in otoprotective capacity. Next generation HGF mimetics are in clinical trials for neurodegenerative diseases and show excellent safety profiles, but neither preclinical studies nor clinical trials have examined hearing loss as a potential consequence of pharmaceutical HGF activation. Further research is needed to determine the consequences of systemic MM-201 application on the auditory system.
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Affiliation(s)
- Phillip M Uribe
- Department of Integrative Physiology and Neuroscience, Washington State University, 14204 NE Salmon Creek Ave, Vancouver, WA 98686 USA
| | - Alexandria M Hudson
- Department of Integrative Physiology and Neuroscience, Washington State University, 14204 NE Salmon Creek Ave, Vancouver, WA 98686 USA
| | - Gavin Lockard
- Department of Integrative Physiology and Neuroscience, Washington State University, 14204 NE Salmon Creek Ave, Vancouver, WA 98686 USA
| | - Meiyan Jiang
- Oregon Hearing Research Center, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Joseph Harding
- Department of Integrative Physiology and Neuroscience, Washington State University, Pullman, WA 99164 USA
| | - Peter S Steyger
- Translational Hearing Center, Creighton University, Omaha, NE, 68178, USA
| | - Allison B Coffin
- Department of Integrative Physiology and Neuroscience, Washington State University, 14204 NE Salmon Creek Ave, Vancouver, WA 98686 USA.
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Smith-Cortinez N, Tan AK, Stokroos RJ, Versnel H, Straatman LV. Regeneration of Hair Cells from Endogenous Otic Progenitors in the Adult Mammalian Cochlea: Understanding Its Origins and Future Directions. Int J Mol Sci 2023; 24:ijms24097840. [PMID: 37175547 PMCID: PMC10177935 DOI: 10.3390/ijms24097840] [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: 03/13/2023] [Revised: 04/20/2023] [Accepted: 04/21/2023] [Indexed: 05/15/2023] Open
Abstract
Sensorineural hearing loss is caused by damage to sensory hair cells and/or spiral ganglion neurons. In non-mammalian species, hair cell regeneration after damage is observed, even in adulthood. Although the neonatal mammalian cochlea carries regenerative potential, the adult cochlea cannot regenerate lost hair cells. The survival of supporting cells with regenerative potential after cochlear trauma in adults is promising for promoting hair cell regeneration through therapeutic approaches. Targeting these cells by manipulating key signaling pathways that control mammalian cochlear development and non-mammalian hair cell regeneration could lead to regeneration of hair cells in the mammalian cochlea. This review discusses the pathways involved in the development of the cochlea and the impact that trauma has on the regenerative capacity of the endogenous progenitor cells. Furthermore, it discusses the effects of manipulating key signaling pathways targeting supporting cells with progenitor potential to promote hair cell regeneration and translates these findings to the human situation. To improve hearing recovery after hearing loss in adults, we propose a combined approach targeting (1) the endogenous progenitor cells by manipulating signaling pathways (Wnt, Notch, Shh, FGF and BMP/TGFβ signaling pathways), (2) by manipulating epigenetic control, and (3) by applying neurotrophic treatments to promote reinnervation.
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Affiliation(s)
- Natalia Smith-Cortinez
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
- UMC Utrecht Brain Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
| | - A Katherine Tan
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
- UMC Utrecht Brain Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
| | - Robert J Stokroos
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
- UMC Utrecht Brain Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
| | - Huib Versnel
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
- UMC Utrecht Brain Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
| | - Louise V Straatman
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
- UMC Utrecht Brain Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
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18
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Pisani A, Paciello F, Del Vecchio V, Malesci R, De Corso E, Cantone E, Fetoni AR. The Role of BDNF as a Biomarker in Cognitive and Sensory Neurodegeneration. J Pers Med 2023; 13:jpm13040652. [PMID: 37109038 PMCID: PMC10140880 DOI: 10.3390/jpm13040652] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/04/2023] [Accepted: 04/08/2023] [Indexed: 04/29/2023] Open
Abstract
Brain-derived neurotrophic factor (BDNF) has a crucial function in the central nervous system and in sensory structures including olfactory and auditory systems. Many studies have highlighted the protective effects of BDNF in the brain, showing how it can promote neuronal growth and survival and modulate synaptic plasticity. On the other hand, conflicting data about BDNF expression and functions in the cochlear and in olfactory structures have been reported. Several clinical and experimental research studies showed alterations in BDNF levels in neurodegenerative diseases affecting the central and peripheral nervous system, suggesting that BDNF can be a promising biomarker in most neurodegenerative conditions, including Alzheimer's disease, shearing loss, or olfactory impairment. Here, we summarize current research concerning BDNF functions in brain and in sensory domains (olfaction and hearing), focusing on the effects of the BDNF/TrkB signalling pathway activation in both physiological and pathological conditions. Finally, we review significant studies highlighting the possibility to target BDNF as a biomarker in early diagnosis of sensory and cognitive neurodegeneration, opening new opportunities to develop effective therapeutic strategies aimed to counteract neurodegeneration.
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Affiliation(s)
- Anna Pisani
- Department of Otolaryngology Head and Neck Surgery, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
| | - Fabiola Paciello
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Valeria Del Vecchio
- Department of Neuroscience, Reproductive Sciences and Dentistry-Audiology Section, University of Naples Federico II, 80131 Naples, Italy
| | - Rita Malesci
- Department of Neuroscience, Reproductive Sciences and Dentistry-Audiology Section, University of Naples Federico II, 80131 Naples, Italy
| | - Eugenio De Corso
- Department of Otolaryngology Head and Neck Surgery, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Elena Cantone
- Department of Neuroscience, Reproductive Sciences and Dentistry-ENT Section, University of Naples Federico II, 80131 Naples, Italy
| | - Anna Rita Fetoni
- Department of Neuroscience, Reproductive Sciences and Dentistry-Audiology Section, University of Naples Federico II, 80131 Naples, Italy
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19
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Al Aameri RFH, Alanisi EMA, Oluwatosin A, Al Sallami D, Sheth S, Alberts I, Patel S, Rybak LP, Ramkumar V. Targeting CXCL1 chemokine signaling for treating cisplatin ototoxicity. Front Immunol 2023; 14:1125948. [PMID: 37063917 PMCID: PMC10102581 DOI: 10.3389/fimmu.2023.1125948] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Accepted: 03/17/2023] [Indexed: 04/03/2023] Open
Abstract
Cisplatin is chemotherapy used for solid tumor treatment like lung, bladder, head and neck, ovarian and testicular cancers. However, cisplatin-induced ototoxicity limits the utility of this agent in cancer patients, especially when dose escalations are needed. Ototoxicity is associated with cochlear cell death through DNA damage, the generation of reactive oxygen species (ROS) and the consequent activation of caspase, glutamate excitotoxicity, inflammation, apoptosis and/or necrosis. Previous studies have demonstrated a role of CXC chemokines in cisplatin ototoxicity. In this study, we investigated the role of CXCL1, a cytokine which increased in the serum and cochlea by 24 h following cisplatin administration. Adult male Wistar rats treated with cisplatin demonstrated significant hearing loss, assessed by auditory brainstem responses (ABRs), hair cell loss and loss of ribbon synapse. Immunohistochemical studies evaluated the levels of CXCL1 along with increased presence of CD68 and CD45-positive immune cells in cochlea. Increases in CXCL1 was time-dependent in the spiral ganglion neurons and organ of Corti and was associated with progressive increases in CD45, CD68 and IBA1-positive immune cells. Trans-tympanic administration of SB225002, a chemical inhibitor of CXCR2 (receptor target for CXCL1) reduced immune cell migration, protected against cisplatin-induced hearing loss and preserved hair cell integrity. We show that SB225002 reduced the expression of CXCL1, NOX3, iNOS, TNF-α, IL-6 and COX-2. Similarly, knockdown of CXCR2 by trans-tympanic administration of CXCR2 siRNA protected against hearing loss and loss of outer hair cells and reduced ribbon synapses. In addition, SB225002 reduced the expression of inflammatory mediators induced by cisplatin. These results implicate the CXCL1 chemokine as an early player in cisplatin ototoxicity, possibly by initiating the immune cascade, and indicate that CXCR2 is a relevant target for treating cisplatin ototoxicity.
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Affiliation(s)
- Raheem F. H. Al Aameri
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Entkhab M. A. Alanisi
- Department of Pharmaceutical Sciences, Larkin University College of Pharmacy, Miami, FL, United States
| | - Adu Oluwatosin
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Dheyaa Al Sallami
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Sandeep Sheth
- Department of Pharmaceutical Sciences, Larkin University College of Pharmacy, Miami, FL, United States
| | - Ian Alberts
- Medical Microbiology, Immunology and Cell Biology (MMICB), Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Shree Patel
- Medical Microbiology, Immunology and Cell Biology (MMICB), Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Leonard P. Rybak
- Department of Surgery, Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Vickram Ramkumar
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, United States
- *Correspondence: Vickram Ramkumar,
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20
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Martins LC, Silva MDS, Pinheiro EF, da Penha LKRL, Passos ADCF, de Moraes SAS, Batista EDJO, Herculano AM, Oliveira KRHM. COCHLEAR GLIAL CELLS MEDIATES GLUTAMATE UPTAKE THROUGH A SODIUM-INDEPENDENT TRANSPORTER. Hear Res 2023; 432:108753. [PMID: 37054532 DOI: 10.1016/j.heares.2023.108753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 03/17/2023] [Accepted: 03/27/2023] [Indexed: 03/30/2023]
Abstract
Since glutamate is the primary excitatory neurotransmitter in the mammalian cochlea, the mechanisms for the removal of glutamate from the synaptic and extrasynaptic spaces are critical for maintaining normal function of this region. Glial cells of inner ear are crucial for regulation of synaptic transmission throughout since it closely interacts with neurons along the entire auditory pathway, however little is known about the activity and expression of glutamate transporters in the cochlea. In this study, using primary cochlear glial cells cultures obtained from newborn Balb/C mice, we determined the activity of a sodium-dependent and sodium-independent glutamate uptake mechanisms by means of High Performance Liquid Chromatography. The sodium-independent glutamate transport has a prominent contribution in cochlear glial cells which is similar to what has been demonstrated in other sensory organs, but it is not found in tissues less susceptible to continuous glutamate-mediated injuries. Our results showed that xCG- system is expressed in CGCs and is the main responsible for sodium-independent glutamate uptake. The identification and characterization of the xCG- transporter in the cochlea suggests a possible role of this transporter in the control of extracellular glutamate concentrations and regulation of redox state, that may aid in the preservation of auditory function.
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Affiliation(s)
- Luana Carvalho Martins
- Laboratory of Experimental Neuropharmacology, Biological Science Institute, UFPa. Belém, PA CEP:66075-110, Brazil
| | - Mateus Dos Santos Silva
- Laboratory of Experimental Neuropharmacology, Biological Science Institute, UFPa. Belém, PA CEP:66075-110, Brazil
| | - Emerson Feio Pinheiro
- Laboratory of Experimental Neuropharmacology, Biological Science Institute, UFPa. Belém, PA CEP:66075-110, Brazil
| | | | | | | | | | - Anderson Manoel Herculano
- Laboratory of Experimental Neuropharmacology, Biological Science Institute, UFPa. Belém, PA CEP:66075-110, Brazil
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21
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Lu ZJ, Ye JG, Wang DL, Li MK, Zhang QK, Liu Z, Huang YJ, Pan CN, Lin YH, Shi ZX, Zheng YF. Integrative Single-Cell RNA-Seq and ATAC-Seq Analysis of Mouse Corneal Epithelial Cells. Invest Ophthalmol Vis Sci 2023; 64:30. [PMID: 36943152 PMCID: PMC10043503 DOI: 10.1167/iovs.64.3.30] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023] Open
Abstract
Purpose Corneal epithelial homeostasis is maintained by coordinated gene expression across distinct cell populations, but the gene regulatory programs underlying this cellular diversity remain to be characterized. Here we applied single-cell multi-omics analysis to delineate the gene regulatory profile of mouse corneal epithelial cells under normal homeostasis. Methods Single cells isolated from the cornea epithelium (with marginal conjunctiva) of adult mice were subjected to scRNA-seq and scATAC-seq using the 10×Genomics platform. Cell types were clustered by the graph-based visualization method uniform manifold approximation and projection and unbiased computational informatics analysis. The scRNA-seq and scATAC-seq datasets were integrated following the integration pipeline described in ArchR and Seurat. Results We characterized diverse corneal epithelial cell types based on gene expression signatures and chromatin accessibility. We found that cell type-specific accessibility regions were mainly located at distal regions, suggesting essential roles of distal regulatory elements in determining corneal epithelial cell diversity. Trajectory analyses revealed a continuum of cell state transition and higher coordination between transcription factor (TF) motif accessibility and gene expression during corneal epithelial cell differentiation. By integrating transcriptomic and chromatin accessibility analysis, we identified cell type-specific and shared gene regulation programs. We also uncovered critical TFs driving corneal epithelial cell differentiation, such as nuclear factor I (NFI) family members, Rarg, Elf3. We found that nuclear factor-κB (NF-κB) family members were positive TFs in limbal cells and some superficial cells, but they were involved in regulating distinct biological processes. Conclusions Our study presents a comprehensive gene regulatory landscape of mouse cornea epithelial cells, and provides valuable foundations for future investigation of corneal epithelial homeostasis in the context of cornea pathologies and regenerative medicine.
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Affiliation(s)
- Zhao-Jing Lu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
- Research Unit of Ocular Development and Regeneration, Chinese Academy of Medical Sciences, China
| | - Jin-Guo Ye
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Dong-Liang Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Meng-Ke Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Qi-Kai Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Zhong Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yan-Jing Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Cai-Neng Pan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yu-Heng Lin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Zhuo-Xing Shi
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Ying-Feng Zheng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
- Research Unit of Ocular Development and Regeneration, Chinese Academy of Medical Sciences, China
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22
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Barnes CC, Yee KT, Vetter DE. Conditional Ablation of Glucocorticoid and Mineralocorticoid Receptors from Cochlear Supporting Cells Reveals Their Differential Roles for Hearing Sensitivity and Dynamics of Recovery from Noise-Induced Hearing Loss. Int J Mol Sci 2023; 24:3320. [PMID: 36834731 PMCID: PMC9961551 DOI: 10.3390/ijms24043320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023] Open
Abstract
Endogenous glucocorticoids (GC) are known to modulate basic elements of cochlear physiology. These include both noise-induced injury and circadian rhythms. While GC signaling in the cochlea can directly influence auditory transduction via actions on hair cells and spiral ganglion neurons, evidence also indicates that GC signaling exerts effects via tissue homeostatic processes that can include effects on cochlear immunomodulation. GCs act at both the glucocorticoid receptor (GR) and the mineralocorticoid receptor (MR). Most cell types in the cochlea express both receptors sensitive to GCs. The GR is associated with acquired sensorineural hearing loss (SNHL) through its effects on both gene expression and immunomodulatory programs. The MR has been associated with age-related hearing loss through dysfunction of ionic homeostatic balance. Cochlear supporting cells maintain local homeostatic requirements, are sensitive to perturbation, and participate in inflammatory signaling. Here, we have used conditional gene manipulation techniques to target Nr3c1 (GR) or Nr3c2 (MR) for tamoxifen-induced gene ablation in Sox9-expressing cochlear supporting cells of adult mice to investigate whether either of the receptors sensitive to GCs plays a role in protecting against (or exacerbating) noise-induced cochlear damage. We have selected mild intensity noise exposure to examine the role of these receptors related to more commonly experienced noise levels. Our results reveal distinct roles of these GC receptors for both basal auditory thresholds prior to noise exposure and during recovery from mild noise exposure. Prior to noise exposure, auditory brainstem responses (ABRs) were measured in mice carrying the floxed allele of interest and the Cre recombinase transgene, but not receiving tamoxifen injections (defined as control (no tamoxifen treatment), versus conditional knockout (cKO) mice, defined as mice having received tamoxifen injections. Results revealed hypersensitive thresholds to mid- to low-frequencies after tamoxifen-induced GR ablation from Sox9-expressing cochlear supporting cells compared to control (no tamoxifen) mice. GR ablation from Sox9-expressing cochlear supporting cells resulted in a permanent threshold shift in mid-basal cochlear frequency regions after mild noise exposure that produced only a temporary threshold shift in both control (no tamoxifen) f/fGR:Sox9iCre+ and heterozygous f/+GR:Sox9iCre+ tamoxifen-treated mice. A similar comparison of basal ABRs measured in control (no tamoxifen) and tamoxifen-treated, floxed MR mice prior to noise exposure indicated no difference in baseline thresholds. After mild noise exposure, MR ablation was initially associated with a complete threshold recovery at 22.6 kHz by 3 days post-noise. Threshold continued to shift to higher sensitivity over time such that by 30 days post-noise exposure the 22.6 kHz ABR threshold was 10 dB more sensitive than baseline. Further, MR ablation produced a temporary reduction in peak 1 neural amplitude one day post-noise. While supporting cell GR ablation trended towards reducing numbers of ribbon synapses, MR ablation reduced ribbon synapse counts but did not exacerbate noise-induced damage including synapse loss at the experimental endpoint. GR ablation from the targeted supporting cells increased the basal resting number of Iba1-positive (innate) immune cells (no noise exposure) and decreased the number of Iba1-positive cells seven days following noise exposure. MR ablation did not alter innate immune cell numbers at seven days post-noise exposure. Taken together, these findings support differential roles of cochlear supporting cell MR and GR expression at basal, resting conditions and especially during recovery from noise exposure.
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Affiliation(s)
- Charles C. Barnes
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Kathleen T. Yee
- Department of Otolaryngology–Head and Neck Surgery, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Douglas E. Vetter
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS 39216, USA
- Department of Otolaryngology–Head and Neck Surgery, University of Mississippi Medical Center, Jackson, MS 39216, USA
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23
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Generation of innervated cochlear organoid recapitulates early development of auditory unit. Stem Cell Reports 2022; 18:319-336. [PMID: 36584686 PMCID: PMC9860115 DOI: 10.1016/j.stemcr.2022.11.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 11/28/2022] [Accepted: 11/30/2022] [Indexed: 12/30/2022] Open
Abstract
Functional cochlear hair cells (HCs) innervated by spiral ganglion neurons (SGNs) are essential for hearing, whereas robust models that recapitulate the peripheral auditory circuity are still lacking. Here, we developed cochlear organoids with functional peripheral auditory circuity in a staging three-dimensional (3D) co-culture system by initially reprogramming cochlear progenitor cells (CPCs) with increased proliferative potency that could be long-term expanded, then stepwise inducing the differentiation of cochlear HCs, as well as the outgrowth of neurites from SGNs. The function of HCs and synapses within organoids was confirmed by a series of morphological and electrophysiological evaluations. Single-cell mRNA sequencing revealed the differentiation trajectories of CPCs toward the major cochlear cell types and the dynamic gene expression during organoid HC development, which resembled the pattern of native HCs. We established the cochlear organoids with functional synapses for the first time, which provides a platform for deciphering the mechanisms of sensorineural hearing loss.
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24
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Cassinotti LR, Ji L, Borges BC, Cass ND, Desai AS, Kohrman DC, Liberman MC, Corfas G. Cochlear Neurotrophin-3 overexpression at mid-life prevents age-related inner hair cell synaptopathy and slows age-related hearing loss. Aging Cell 2022; 21:e13708. [PMID: 36088647 PMCID: PMC9577954 DOI: 10.1111/acel.13708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 08/02/2022] [Accepted: 08/21/2022] [Indexed: 01/25/2023] Open
Abstract
Age-related hearing loss (ARHL) is the most prevalent sensory deficit in the elderly. This progressive pathology often has psychological and medical comorbidities, including social isolation, depression, and cognitive decline. Despite ARHL's enormous societal and economic impact, no therapies to prevent or slow its progression exist. Loss of synapses between inner hair cells (IHCs) and spiral ganglion neurons (SGNs), a.k.a. IHC synaptopathy, is an early event in cochlear aging, preceding neuronal and hair cell loss. To determine if age-related IHC synaptopathy can be prevented, and if this impacts the time-course of ARHL, we tested the effects of cochlear overexpression of neurotrophin-3 (Ntf3) starting at middle age. We chose Ntf3 because this neurotrophin regulates the formation of IHC-SGN synapses in the neonatal period. We now show that triggering Ntf3 overexpression by IHC supporting cells starting in middle age rapidly increases the amplitude of sound-evoked neural potentials compared with age-matched controls, indicating that Ntf3 produces a positive effect on cochlear function when the pathology is minimal. Furthermore, near the end of their lifespan, Ntf3-overexpressing mice have milder ARHL, with larger sound-evoked potentials along the ascending auditory pathway and reduced IHC synaptopathy compared with age-matched controls. Our results also provide evidence that an age-related decrease in cochlear Ntf3 expression contributes to ARHL and that Ntf3 supplementation could serve as a therapeutic for this prevalent disorder. Furthermore, these findings suggest that factors that regulate synaptogenesis during development could prevent age-related synaptopathy in the brain, a process involved in several central nervous system degenerative disorders.
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Affiliation(s)
- Luis R. Cassinotti
- Kresge Hearing Research Institute and Department of Otolaryngology‐Head and Neck SurgeryUniversity of MichiganAnn ArborMichiganUSA
| | - Lingchao Ji
- Kresge Hearing Research Institute and Department of Otolaryngology‐Head and Neck SurgeryUniversity of MichiganAnn ArborMichiganUSA
- Present address:
Peking University Shenzhen HospitalShenzhenChina
| | - Beatriz C. Borges
- Kresge Hearing Research Institute and Department of Otolaryngology‐Head and Neck SurgeryUniversity of MichiganAnn ArborMichiganUSA
| | - Nathan D. Cass
- Kresge Hearing Research Institute and Department of Otolaryngology‐Head and Neck SurgeryUniversity of MichiganAnn ArborMichiganUSA
- Present address:
The Otology Group of Vanderbilt, Vanderbilt University Medical Center Department of OtolaryngologyNashvilleTennesseeUSA
| | - Aditi S. Desai
- Kresge Hearing Research Institute and Department of Otolaryngology‐Head and Neck SurgeryUniversity of MichiganAnn ArborMichiganUSA
| | - David C. Kohrman
- Kresge Hearing Research Institute and Department of Otolaryngology‐Head and Neck SurgeryUniversity of MichiganAnn ArborMichiganUSA
| | - M. Charles Liberman
- Eaton‐Peabody Laboratories, Massachusetts Eye & Ear, and Department of Otolaryngology, Head and Neck SurgeryHarvard Medical SchoolBostonMassachusettsUSA
| | - Gabriel Corfas
- Kresge Hearing Research Institute and Department of Otolaryngology‐Head and Neck SurgeryUniversity of MichiganAnn ArborMichiganUSA
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25
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Auditory neuropathy: from etiology to management. Curr Opin Otolaryngol Head Neck Surg 2022; 30:332-338. [PMID: 35939320 DOI: 10.1097/moo.0000000000000829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
PURPOSE OF REVIEW Auditory neuropathy is a disorder of auditory dysfunction characterized by the normal function of the outer hair cells and malfunction of the inner hair cells, synapses, postsynapses and/or auditory afferent nervous system. This review summarizes the process of discovery and naming of auditory neuropathy and describes the acquired, associated genetic disorders and management available. RECENT FINDINGS In the last 40 years, auditory neuropathy has undergone a process of discovery, naming and progressive elucidation of its complex pathological mechanisms. Recent studies have revealed numerous acquired and inherited causative factors associated with auditory neuropathy. Studies have analyzed the pathogenic mechanisms of various genes and the outcomes of cochlear implantation. New therapeutic approaches, such as stem cell therapy and gene therapy are the future trends in the treatment of auditory neuropathy. SUMMARY A comprehensive understanding of the pathogenic mechanisms is crucial in illustrating auditory neuropathy and assist in developing future management strategies.
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26
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Effects of pyrroloquinoline quinone on noise-induced and age-related hearing loss in mice. Sci Rep 2022; 12:15911. [PMID: 36151123 PMCID: PMC9508078 DOI: 10.1038/s41598-022-19842-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 09/05/2022] [Indexed: 11/10/2022] Open
Abstract
We investigated whether the oxidoreductase cofactor pyrroloquinoline quinone (PQQ) prevents noise-induced and age-related hearing loss (NIHL and ARHL) in mice. To assess NIHL, 8 week-old mice with and without PQQ administration were exposed to noise for 4 h. PQQ was orally administered for one week before and after noise exposure and subcutaneously once before noise exposure. For ARHL evaluation, mice were given drinking water with or without PQQ starting at 2 months of age. In the NIHL model, PQQ-treated mice had auditory brainstem response (ABR) thresholds of significantly reduced elevation at 8 kHz, a significantly increased number of hair cells at the basal turn, and significantly better maintained synapses beneath the inner hair cells compared to controls. In the ARHL model, PQQ significantly attenuated the age-related increase in ABR thresholds at 8 and 32 kHz at 10 months of age compared to controls. In addition, the hair cells, spiral ganglion cells, ribbon synapses, stria vascularis and nerve fibers were all significantly better maintained in PQQ-treated animals compared to controls at 10 months of age. These physiological and histological results demonstrate that PQQ protects the auditory system from NIHL and ARHL in mice.
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27
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Ren H, Hu B, Jiang G. Advancements in prevention and intervention of sensorineural hearing loss. Ther Adv Chronic Dis 2022; 13:20406223221104987. [PMID: 35782345 PMCID: PMC9243368 DOI: 10.1177/20406223221104987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 05/16/2022] [Indexed: 11/28/2022] Open
Abstract
The inner ear is a complex and difficult organ to study, and sensorineural hearing loss (SNHL) is a multifactorial sensorineural disorder with characteristics of impaired speech discrimination, recognition, sound detection, and localization. Till now, SNHL is recognized as an incurable disease because the potential mechanisms underlying SNHL have not been elucidated. The risk of developing SNHL is no longer viewed as primarily due to environmental factors. Instead, SNHL seems to result from a complicated interplay of genetic and environmental factors affecting numerous fundamental cellular processes. The complexity of SNHL is presented as an inability to make an early diagnosis at the earliest stages of the disease and difficulties in the management of symptoms during the process. To date, there are no treatments that slow the neurodegenerative process. In this article, we review the recent advances about SHNL and discuss the complexities and challenges of prevention and intervention of SNHL.
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Affiliation(s)
- Hongmiao Ren
- Otorhinolaryngology Hospital, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, Guangdong, P.R. China
| | - Bing Hu
- Department of Otolaryngology Head and Neck Surgery, The First Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
| | - Guangli Jiang
- Otorhinolaryngology Hospital, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
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28
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Bieniussa L, Kahraman B, Skornicka J, Schulte A, Voelker J, Jablonka S, Hagen R, Rak K. Pegylated Insulin-Like Growth Factor 1 attenuates Hair Cell Loss and promotes Presynaptic Maintenance of Medial Olivocochlear Cholinergic Fibers in the Cochlea of the Progressive Motor Neuropathy Mouse. Front Neurol 2022; 13:885026. [PMID: 35720065 PMCID: PMC9203726 DOI: 10.3389/fneur.2022.885026] [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: 02/27/2022] [Accepted: 04/26/2022] [Indexed: 11/13/2022] Open
Abstract
The progressive motor neuropathy (PMN) mouse is a model of an inherited motor neuropathy disease with progressive neurodegeneration. Axon degeneration associates with homozygous mutations of the TBCE gene encoding the tubulin chaperone E protein. TBCE is responsible for the correct dimerization of alpha and beta-tubulin. Strikingly, the PMN mouse also develops a progressive hearing loss after normal hearing onset, characterized by degeneration of the auditory nerve and outer hair cell (OHC) loss. However, the development of this neuronal and cochlear pathology is not fully understood yet. Previous studies with pegylated insulin-like growth factor 1 (peg-IGF-1) treatment in this mouse model have been shown to expand lifespan, weight, muscle strength, and motor coordination. Accordingly, peg-IGF-1 was evaluated for an otoprotective effect. We investigated the effect of peg-IGF-1 on the auditory system by treatment starting at postnatal day 15 (p15). Histological analysis revealed positive effects on OHC synapses of medial olivocochlear (MOC) neuronal fibers and a short-term attenuation of OHC loss. Peg-IGF-1 was able to conditionally restore the disorganization of OHC synapses and maintain the provision of cholinergic acetyltransferase in presynapses. To assess auditory function, frequency-specific auditory brainstem responses and distortion product otoacoustic emissions were recorded in animals on p21 and p28. However, despite the positive effect on MOC fibers and OHC, no restoration of hearing could be achieved. The present work demonstrates that the synaptic pathology of efferent MOC fibers in PMN mice represents a particular form of “efferent auditory neuropathy.” Peg-IGF-1 showed an otoprotective effect by preventing the degeneration of OHCs and efferent synapses. However, enhanced efforts are needed to optimize the treatment to obtain detectable improvements in hearing performances.
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Affiliation(s)
- Linda Bieniussa
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University Hospital Würzburg, Würzburg, Germany
| | - Baran Kahraman
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University Hospital Würzburg, Würzburg, Germany
| | - Johannes Skornicka
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University Hospital Würzburg, Würzburg, Germany
| | - Annemarie Schulte
- Department of Neurology, University Hospital Würzburg, Würzburg, Germany
| | - Johannes Voelker
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University Hospital Würzburg, Würzburg, Germany
| | - Sibylle Jablonka
- Institute of Clinical Neurobiology, University of Würzburg, Würzburg, Germany
| | - Rudolf Hagen
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University Hospital Würzburg, Würzburg, Germany
| | - Kristen Rak
- Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University Hospital Würzburg, Würzburg, Germany
- *Correspondence: Kristen Rak
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29
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Mukhopadhyay M, Pangrsic T. Synaptic transmission at the vestibular hair cells of amniotes. Mol Cell Neurosci 2022; 121:103749. [PMID: 35667549 DOI: 10.1016/j.mcn.2022.103749] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 05/09/2022] [Accepted: 06/01/2022] [Indexed: 11/19/2022] Open
Abstract
A harmonized interplay between the central nervous system and the five peripheral end organs is how the vestibular system helps organisms feel a sense of balance and motion in three-dimensional space. The receptor cells of this system, much like their cochlear equivalents, are the specialized hair cells. However, research over the years has shown that the vestibular endorgans and hair cells evolved very differently from their cochlear counterparts. The structurally unique calyceal synapse, which appeared much later in the evolutionary time scale, and continues to intrigue researchers, is now known to support several forms of synaptic neurotransmission. The conventional quantal transmission is believed to employ the ribbon structures, which carry several tethered vesicles filled with neurotransmitters. However, the field of vestibular hair cell synaptic molecular anatomy is still at a nascent stage and needs further work. In this review, we will touch upon the basic structure and function of the peripheral vestibular system, with the focus on the various modes of neurotransmission at the type I vestibular hair cells. We will also shed light on the current knowledge about the molecular anatomy of the vestibular hair cell synapses and vestibular synaptopathy.
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Affiliation(s)
- Mohona Mukhopadhyay
- Experimental Otology Group, InnerEarLab, Department of Otolaryngology, University Medical Center Göttingen, and Institute for Auditory Neuroscience, 37075 Göttingen, Germany
| | - Tina Pangrsic
- Experimental Otology Group, InnerEarLab, Department of Otolaryngology, University Medical Center Göttingen, and Institute for Auditory Neuroscience, 37075 Göttingen, Germany; Auditory Neuroscience Group, Max Planck Institute for Multidisciplinary Sciences, 37075 Göttingen, Germany; Collaborative Research Center 889, University of Göttingen, Göttingen, Germany; Multiscale Bioimaging Cluster of Excellence (MBExC), University of Göttingen, 37075 Göttingen, Germany.
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St. Peter M, Brough DE, Lawrence A, Nelson-Brantley J, Huang P, Harre J, Warnecke A, Staecker H. Improving Control of Gene Therapy-Based Neurotrophin Delivery for Inner Ear Applications. Front Bioeng Biotechnol 2022; 10:892969. [PMID: 35721868 PMCID: PMC9204055 DOI: 10.3389/fbioe.2022.892969] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 04/27/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Survival and integrity of the spiral ganglion is vital for hearing in background noise and for optimal functioning of cochlear implants. Numerous studies have demonstrated that supplementation of supraphysiologic levels of the neurotrophins BDNF and NT-3 by pumps or gene therapy strategies supports spiral ganglion survival. The endogenous physiological levels of growth factors within the inner ear, although difficult to determine, are likely extremely low within the normal inner ear. Thus, novel approaches for the long-term low-level delivery of neurotrophins may be advantageous. Objectives: This study aimed to evaluate the long-term effects of gene therapy-based low-level neurotrophin supplementation on spiral ganglion survival. Using an adenovirus serotype 28-derived adenovector delivery system, the herpes latency promoter, a weak, long expressing promoter system, has been used to deliver the BDNF or NTF3 genes to the inner ear after neomycin-induced ototoxic injury in mice. Results: Treatment of the adult mouse inner ear with neomycin resulted in acute and chronic changes in endogenous neurotrophic factor gene expression and led to a degeneration of spiral ganglion cells. Increased survival of spiral ganglion cells after adenoviral delivery of BDNF or NTF3 to the inner ear was observed. Expression of BDNF and NT-3 could be demonstrated in the damaged organ of Corti after gene delivery. Hearing loss due to overexpression of neurotrophins in the normal hearing ear was avoided when using this novel vector–promoter combination. Conclusion: Combining supporting cell-specific gene delivery via the adenovirus serotype 28 vector with a low-strength long expressing promoter potentially can provide long-term neurotrophin delivery to the damaged inner ear.
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Affiliation(s)
| | | | - Anna Lawrence
- Department of Otolaryngology, University of Kansas School of Medicine, Kansas City, KS, United States
| | | | - Peixin Huang
- Department of Otolaryngology, University of Kansas School of Medicine, Kansas City, KS, United States
| | - Jennifer Harre
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Athanasia Warnecke
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Hinrich Staecker
- Department of Otolaryngology, University of Kansas School of Medicine, Kansas City, KS, United States
- *Correspondence: Hinrich Staecker,
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31
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Le Prell CG. Prevention of Noise-Induced Hearing Loss Using Investigational Medicines for the Inner Ear: Previous Trial Outcomes Should Inform Future Trial Design. Antioxid Redox Signal 2022; 36:1171-1202. [PMID: 34346254 PMCID: PMC9221155 DOI: 10.1089/ars.2021.0166] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 07/25/2021] [Indexed: 11/13/2022]
Abstract
Significance: Noise-induced hearing loss (NIHL) is an important public health issue resulting in decreased quality of life for affected individuals, and significant costs to employers and governmental agencies. Recent Advances: Advances in the mechanistic understanding of NIHL have prompted a growing number of proposed, in-progress, and completed clinical trials for possible protections against NIHL via antioxidants and other drug agents. Thirty-one clinical trials evaluating prevention of either temporary or permanent NIHL were identified and are reviewed. Critical Issues: This review revealed little consistency in the noise-exposed populations in which drugs are evaluated or the primary outcomes used to measure NIHL prevention. Changes in pure-tone thresholds were the most common primary outcomes; specific threshold metrics included both average hearing loss and incidence of significant hearing loss. Changes in otoacoustic emission (OAE) amplitude were relatively common secondary outcomes. Extended high-frequency (EHF) hearing and speech-in-noise perception are commonly adversely affected by noise exposure but are not consistently included in clinical trials assessing prevention of NIHL. Future Directions: Multiple criteria are available for monitoring NIHL, but the specific criterion to be used to define clinically significant otoprotection remains a topic of discussion. Audiogram-based primary outcome measures can be combined with secondary outcomes, including OAE amplitude, EHF hearing, speech-in-noise testing, tinnitus surveys, and patient-reported outcomes. Standardization of test protocols for the above primary and secondary outcomes, and associated reporting criterion for each, would facilitate clinical trial design and comparison of results across investigational drug agents. Antioxid. Redox Signal. 36, 1171-1202.
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Affiliation(s)
- Colleen G. Le Prell
- Department of Speech, Language, and Hearing Science, University of Texas at Dallas, Richardson, Texas, USA
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32
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Abstract
INTRODUCTION More than 5% of the world's population have a disabling hearing loss which can be managed by hearing aids or implanted electrical devices. However, outcomes are highly variable, and the sound perceived by recipients is far from perfect. Sparked by the discovery of progenitor cells in the cochlea and rapid progress in drug delivery to the cochlea, biological and pharmaceutical therapies are currently in development to improve the function of the cochlear implant or eliminate the need for it altogether. AREAS COVERED This review highlights progress in emerging regenerative strategies to restore hearing and adjunct therapies to augment the cochlear implant. Novel approaches include the reprogramming of progenitor cells to restore the sensory hair cell population in the cochlea, gene therapy and gene editing to treat hereditary and acquired hearing loss. A detailed review of optogenetics is also presented as a technique that could enable optical stimulation of the spiral ganglion neurons, replacing or complementing electrical stimulation. EXPERT OPINION Increasing evidence of substantial reversal of hearing loss in animal models, alongside rapid advances in delivery strategies to the cochlea and learnings from clinical trials will amalgamate into a biological or pharmaceutical therapy to replace or complement the cochlear implant.
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Affiliation(s)
- Elise Ajay
- Bionics Institute, East Melbourne, Victoria, Australia.,University of Melbourne, Department of Engineering
| | | | - Rachael Richardson
- Bionics Institute, East Melbourne, Victoria, Australia.,University of Melbourne, Medical Bionics Department, Parkville, Victoria, Australia.,University of Melbourne, Department of Surgery (Otolaryngology), East Melbourne, Victoria, Australia
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33
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Wu F, Hill K, Fang Q, He Z, Zheng H, Wang X, Xiong H, Sha SH. Traumatic-noise-induced hair cell death and hearing loss is mediated by activation of CaMKKβ. Cell Mol Life Sci 2022; 79:249. [PMID: 35438341 PMCID: PMC9844253 DOI: 10.1007/s00018-022-04268-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 03/14/2022] [Accepted: 03/20/2022] [Indexed: 01/19/2023]
Abstract
BACKGROUND The Ca2+/calmodulin-dependent protein kinase kinases (CaMKKs) are serine/threonine-directed protein kinases that are activated following increases in intracellular calcium, playing a critical role in neuronal signaling. Inner-ear-trauma-induced calcium overload in sensory hair cells has been well documented in the pathogenesis of traumatic noise-induced hair cell death and hearing loss, but there are no established pharmaceutical therapies available due to a lack of specific therapeutic targets. In this study, we investigated the activation of CaMKKβ in the inner ear after traumatic noise exposure and assessed the prevention of noise-induced hearing loss (NIHL) with RNA silencing. RESULTS Treatment with short hairpin RNA of CaMKKβ (shCaMKKβ) via adeno-associated virus transduction significantly knocked down CaMKKβ expression in the inner ear. Knockdown of CaMKKβ significantly attenuated noise-induced hair cell loss and hearing loss (NIHL). Additionally, pretreatment with naked CaMKKβ small interfering RNA (siCaMKKβ) attenuated noise-induced losses of inner hair cell synapses and OHCs and NIHL. Furthermore, traumatic noise exposure activates CaMKKβ in OHCs as demonstrated by immunolabeling for p-CaMKI. CaMKKβ mRNA assessed by fluorescence in-situ hybridization and immunolabeling for CaMKKβ in OHCs also increased after the exposure. Finally, pretreatment with siCaMKKβ diminished noise-induced activation of AMPKα in OHCs. CONCLUSIONS These findings demonstrate that traumatic-noise-induced OHC loss and hearing loss occur primarily via activation of CaMKKβ. Targeting CaMKKβ is a key strategy for prevention of noise-induced hearing loss. Furthermore, our data suggest that noise-induced activation of AMPKα in OHCs occurs via the CaMKKβ pathway.
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Affiliation(s)
- Fan Wu
- Department of Pathology and Laboratory Medicine, The Medical University of South Carolina, Charleston, SC 29425, USA.,Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Kayla Hill
- Department of Pathology and Laboratory Medicine, The Medical University of South Carolina, Charleston, SC 29425, USA
| | - Qiaojun Fang
- Department of Pathology and Laboratory Medicine, The Medical University of South Carolina, Charleston, SC 29425, USA.,School of Life Sciences and Technology, Southeast University, Nanjing 210096, China
| | - Zuhong He
- Department of Pathology and Laboratory Medicine, The Medical University of South Carolina, Charleston, SC 29425, USA
| | - Hongwei Zheng
- Department of Pathology and Laboratory Medicine, The Medical University of South Carolina, Charleston, SC 29425, USA
| | - Xianren Wang
- Department of Pathology and Laboratory Medicine, The Medical University of South Carolina, Charleston, SC 29425, USA
| | - Hao Xiong
- Department of Pathology and Laboratory Medicine, The Medical University of South Carolina, Charleston, SC 29425, USA
| | - Su-Hua Sha
- Department of Pathology and Laboratory Medicine, The Medical University of South Carolina, Charleston, SC 29425, USA.,Correspondence should be addressed to: Dr. Su-Hua Sha • Department of Pathology and Laboratory Medicine • Medical University of South Carolina • Walton Research Building, Room 403-E • 39 Sabin Street, Charleston, SC 29425, USA. Telephone: 843-792-8324; Fax: 843-792-0368;
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34
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Mukherjee S, Kuroiwa M, Oakden W, Paul BT, Noman A, Chen J, Lin V, Dimitrijevic A, Stanisz G, Le TN. Local magnetic delivery of adeno-associated virus AAV2(quad Y-F)-mediated BDNF gene therapy restores hearing after noise injury. Mol Ther 2022; 30:519-533. [PMID: 34298130 PMCID: PMC8821893 DOI: 10.1016/j.ymthe.2021.07.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 05/11/2021] [Accepted: 07/14/2021] [Indexed: 02/04/2023] Open
Abstract
Moderate noise exposure may cause acute loss of cochlear synapses without affecting the cochlear hair cells and hearing threshold; thus, it remains "hidden" to standard clinical tests. This cochlear synaptopathy is one of the main pathologies of noise-induced hearing loss (NIHL). There is no effective treatment for NIHL, mainly because of the lack of a proper drug-delivery technique. We hypothesized that local magnetic delivery of gene therapy into the inner ear could be beneficial for NIHL. In this study, we used superparamagnetic iron oxide nanoparticles (SPIONs) and a recombinant adeno-associated virus (AAV) vector (AAV2(quad Y-F)) to deliver brain-derived neurotrophic factor (BDNF) gene therapy into the rat inner ear via minimally invasive magnetic targeting. We found that the magnetic targeting effectively accumulates and distributes the SPION-tagged AAV2(quad Y-F)-BDNF vector into the inner ear. We also found that AAV2(quad Y-F) efficiently transfects cochlear hair cells and enhances BDNF gene expression. Enhanced BDNF gene expression substantially recovers noise-induced BDNF gene downregulation, auditory brainstem response (ABR) wave I amplitude reduction, and synapse loss. These results suggest that magnetic targeting of AAV2(quad Y-F)-mediated BDNF gene therapy could reverse cochlear synaptopathy after NIHL.
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Affiliation(s)
- Subhendu Mukherjee
- Biological Sciences Platform, Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
| | - Maya Kuroiwa
- Department of Otolaryngology Head & Neck Surgery, Faculty of Medicine, University of Toronto, ON M5S 1A1, Canada
| | - Wendy Oakden
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
| | - Brandon T. Paul
- Evaluative Clinical Sciences Platform, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
| | - Ayesha Noman
- Biological Sciences Platform, Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
| | - Joseph Chen
- Department of Otolaryngology Head & Neck Surgery, Faculty of Medicine, University of Toronto, ON M5S 1A1, Canada
| | - Vincent Lin
- Biological Sciences Platform, Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada,Department of Otolaryngology Head & Neck Surgery, Faculty of Medicine, University of Toronto, ON M5S 1A1, Canada
| | - Andrew Dimitrijevic
- Evaluative Clinical Sciences Platform, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada,Department of Otolaryngology Head & Neck Surgery, Faculty of Medicine, University of Toronto, ON M5S 1A1, Canada
| | - Greg Stanisz
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
| | - Trung N. Le
- Biological Sciences Platform, Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada,Department of Otolaryngology Head & Neck Surgery, Faculty of Medicine, University of Toronto, ON M5S 1A1, Canada,Corresponding author: Trung N. Le, Biological Sciences Platform, Hurvitz Brain Sciences Program, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Room M1 102, Toronto, ON M4N 3M5, Canada.
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35
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Li W, Quan Y, Huang M, Wei W, Shu Y, Li H, Chen ZY. A Novel in vitro Model Delineating Hair Cell Regeneration and Neural Reinnervation in Adult Mouse Cochlea. Front Mol Neurosci 2022; 14:757831. [PMID: 35082601 PMCID: PMC8785685 DOI: 10.3389/fnmol.2021.757831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 12/07/2021] [Indexed: 11/13/2022] Open
Abstract
The study of an adult mammalian auditory system, such as regeneration, has been hampered by the lack of an in vitro system in which hypotheses can be tested efficiently. This is primarily due to the fact that the adult inner ear is encased in the toughest bone of the body, whereas its removal leads to the death of the sensory epithelium in culture. We hypothesized that we could take advantage of the integral cochlear structure to maintain the overall inner ear architecture and improve sensory epithelium survival in culture. We showed that by culturing adult mouse cochlea with the (surrounding) bone intact, the supporting cells (SCs) survived and almost all hair cells (HCs) degenerated. To evaluate the utility of the explant culture system, we demonstrated that the overexpression of Atoh1, an HC fate-determining factor, is sufficient to induce transdifferentiation of adult SCs to HC-like cells (HCLCs). Transdifferentiation-derived HCLCs resemble developmentally young HCs and are able to attract adult ganglion neurites. Furthermore, using a damage model, we showed that degenerated adult ganglions respond to regenerated HCLCs by directional neurite outgrowth that leads to HCLC-neuron contacts, strongly supporting the intrinsic properties of the HCLCs in establishing HCLC-neuron connections. The adult whole cochlear explant culture is suitable for diverse studies of the adult inner ear including regeneration, HC-neuron pathways, and inner ear drug screening.
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Affiliation(s)
- Wenyan Li
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, United States
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, MA, United States
- ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
- Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Yizhou Quan
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, United States
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, MA, United States
| | - Mingqian Huang
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, United States
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, MA, United States
| | - Wei Wei
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, United States
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, MA, United States
| | - Yilai Shu
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, United States
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, MA, United States
- ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
- Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Huawei Li
- ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
- Institutes of Biomedical Sciences, Fudan University, Shanghai, China
- *Correspondence: Huawei Li,
| | - Zheng-Yi Chen
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, United States
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, MA, United States
- Zheng-Yi Chen,
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36
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Zhang L, Chen S, Sun Y. Mechanism and Prevention of Spiral Ganglion Neuron Degeneration in the Cochlea. Front Cell Neurosci 2022; 15:814891. [PMID: 35069120 PMCID: PMC8766678 DOI: 10.3389/fncel.2021.814891] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Accepted: 12/09/2021] [Indexed: 12/14/2022] Open
Abstract
Sensorineural hearing loss (SNHL) is one of the most prevalent sensory deficits in humans, and approximately 360 million people worldwide are affected. The current treatment option for severe to profound hearing loss is cochlear implantation (CI), but its treatment efficacy is related to the survival of spiral ganglion neurons (SGNs). SGNs are the primary sensory neurons, transmitting complex acoustic information from hair cells to second-order sensory neurons in the cochlear nucleus. In mammals, SGNs have very limited regeneration ability, and SGN loss causes irreversible hearing loss. In most cases of SNHL, SGN damage is the dominant pathogenesis, and it could be caused by noise exposure, ototoxic drugs, hereditary defects, presbycusis, etc. Tremendous efforts have been made to identify novel treatments to prevent or reverse the damage to SGNs, including gene therapy and stem cell therapy. This review summarizes the major causes and the corresponding mechanisms of SGN loss and the current protection strategies, especially gene therapy and stem cell therapy, to promote the development of new therapeutic methods.
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Affiliation(s)
- Li Zhang
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Sen Chen
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yu Sun
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Institute of Otorhinolaryngology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- *Correspondence: Yu Sun,
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37
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Yu C, Gao HM, Wan G. Macrophages Are Dispensable for Postnatal Pruning of the Cochlear Ribbon Synapses. Front Cell Neurosci 2021; 15:736120. [PMID: 34744631 PMCID: PMC8566810 DOI: 10.3389/fncel.2021.736120] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 10/05/2021] [Indexed: 11/15/2022] Open
Abstract
Ribbon synapses of cochlear hair cells undergo pruning and maturation before the hearing onset. In the central nervous system (CNS), synaptic pruning was mediated by microglia, the brain-resident macrophages, via activation of the complement system. Whether a similar mechanism regulates ribbon synapse pruning is currently unknown. In this study, we report that the densities of cochlear macrophages surrounding hair cells were highest at around P8, corresponding well to the completion of ribbon synaptic pruning by P8–P9. Surprisingly, using multiple genetic mouse models, we found that postnatal pruning of the ribbon synapses and auditory functions were unaffected by the knockout of the complement receptor 3 (CR3) or by ablations of macrophages expressing either LysM or Cx3cr1. Our results suggest that unlike microglia in the CNS, macrophages in the cochlea do not mediate pruning of the cochlear ribbon synapses.
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Affiliation(s)
- Chaorong Yu
- MOE Key Laboratory of Model Animal for Disease Study, Department of Otorhinolaryngology-Head and Neck Surgery, The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical School, Nanjing University, Nanjing, China.,Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Hui-Ming Gao
- MOE Key Laboratory of Model Animal for Disease Study, Department of Otorhinolaryngology-Head and Neck Surgery, The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical School, Nanjing University, Nanjing, China.,Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China.,Institute for Brain Sciences, Nanjing University, Nanjing, China
| | - Guoqiang Wan
- MOE Key Laboratory of Model Animal for Disease Study, Department of Otorhinolaryngology-Head and Neck Surgery, The Affiliated Drum Tower Hospital of Medical School, Model Animal Research Center of Medical School, Nanjing University, Nanjing, China.,Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China.,Institute for Brain Sciences, Nanjing University, Nanjing, China.,Research Institute of Otolaryngology, Nanjing, China
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38
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Holmgren M, Ravicz ME, Hancock KE, Strelkova O, Kallogjeri D, Indzhykulian AA, Warchol ME, Sheets L. Mechanical overstimulation causes acute injury and synapse loss followed by fast recovery in lateral-line neuromasts of larval zebrafish. eLife 2021; 10:69264. [PMID: 34665127 PMCID: PMC8555980 DOI: 10.7554/elife.69264] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 10/18/2021] [Indexed: 12/14/2022] Open
Abstract
Excess noise damages sensory hair cells, resulting in loss of synaptic connections with auditory nerves and, in some cases, hair-cell death. The cellular mechanisms underlying mechanically induced hair-cell damage and subsequent repair are not completely understood. Hair cells in neuromasts of larval zebrafish are structurally and functionally comparable to mammalian hair cells but undergo robust regeneration following ototoxic damage. We therefore developed a model for mechanically induced hair-cell damage in this highly tractable system. Free swimming larvae exposed to strong water wave stimulus for 2 hr displayed mechanical injury to neuromasts, including afferent neurite retraction, damaged hair bundles, and reduced mechanotransduction. Synapse loss was observed in apparently intact exposed neuromasts, and this loss was exacerbated by inhibiting glutamate uptake. Mechanical damage also elicited an inflammatory response and macrophage recruitment. Remarkably, neuromast hair-cell morphology and mechanotransduction recovered within hours following exposure, suggesting severely damaged neuromasts undergo repair. Our results indicate functional changes and synapse loss in mechanically damaged lateral-line neuromasts that share key features of damage observed in noise-exposed mammalian ear. Yet, unlike the mammalian ear, mechanical damage to neuromasts is rapidly reversible.
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Affiliation(s)
- Melanie Holmgren
- Department of Otolaryngology, Washington University School of Medicine, St Louis, United States
| | - Michael E Ravicz
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear, Boston, United States.,Department of Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston, United States
| | - Kenneth E Hancock
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear, Boston, United States.,Department of Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston, United States
| | - Olga Strelkova
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear, Boston, United States.,Department of Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston, United States
| | - Dorina Kallogjeri
- Department of Otolaryngology, Washington University School of Medicine, St Louis, United States
| | - Artur A Indzhykulian
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear, Boston, United States.,Department of Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston, United States
| | - Mark E Warchol
- Department of Otolaryngology, Washington University School of Medicine, St Louis, United States.,Department of Neuroscience, Washington University School of Medicine, St Louis, United States
| | - Lavinia Sheets
- Department of Otolaryngology, Washington University School of Medicine, St Louis, United States.,Department of Developmental Biology, Washington University School of Medicine, St. Louis, United States
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39
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Hosoya M, Fujioka M, Murayama AY, Ozawa H, Okano H, Ogawa K. Neuronal development in the cochlea of a nonhuman primate model, the common marmoset. Dev Neurobiol 2021; 81:905-938. [PMID: 34545999 PMCID: PMC9298346 DOI: 10.1002/dneu.22850] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 08/25/2021] [Accepted: 09/13/2021] [Indexed: 01/02/2023]
Abstract
Precise cochlear neuronal development is vital to hearing ability. Understanding the developmental process of the spiral ganglion is useful for studying hearing loss aimed at aging or regenerative therapy. Although interspecies differences have been reported between rodents and humans, to date, most of our knowledge about the development of cochlear neuronal development has been obtained from rodent models because of the difficulty in using human fetal samples in this field. In this study, we investigated cochlear neuronal development in a small New World monkey species, the common marmoset (Callithrix jacchus). We examined more than 25 genes involved in the neuronal development of the cochlea and described the critical developmental steps of these neurons. We also revealed similarities and differences between previously reported rodent models and this primate animal model. Our results clarified that this animal model of cochlear neuronal development is more similar to humans than rodents and is suitable as an alternative for the analysis of human cochlear development. The time course established in this report will be a useful tool for studying primate‐specific neuronal biology of the inner ear, which could eventually lead to new treatment strategies for human hearing loss.
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Affiliation(s)
- Makoto Hosoya
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Masato Fujioka
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Ayako Y Murayama
- Department of Physiology, Keio University School of Medicine, Tokyo, Japan.,Laboratory for Marmoset Neural Architecture, Center for Brain Science, RIKEN, Wako, Japan
| | - Hiroyuki Ozawa
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, Tokyo, Japan.,Laboratory for Marmoset Neural Architecture, Center for Brain Science, RIKEN, Wako, Japan
| | - Kaoru Ogawa
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan
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40
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Kempfle JS. Endoscopic-Assisted Drug Delivery for Inner Ear Regeneration. Otolaryngol Clin North Am 2021; 54:189-200. [PMID: 33243375 DOI: 10.1016/j.otc.2020.09.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sensorineural hearing loss is caused by irreversible loss of auditory hair cells and/or neurons and is increasing in prevalence. Hair cells and neurons do not regenerate after damage, but novel regeneration therapies based on small molecule drugs, gene therapy, and cell replacement strategies offer promising therapeutic options. Endogenous and exogenous regeneration techniques are discussed in context of their feasibility for hair cell and neuron regeneration. Gene therapy and treatment of synaptopathy represent promising future therapies. Minimally invasive endoscopic ear surgery offers a viable approach to aid in delivery of pharmacologic compounds, cells, or viral vectors to the inner ear for all of these techniques.
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Affiliation(s)
- Judith S Kempfle
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Eaton-Peabody Laboratories, C360, 243 Charles Street, Boston, MA 02114, USA.
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Kempfle JS, Duro MV, Zhang A, Amador CD, Kuang R, Lu R, Kashemirov BA, Edge AS, McKenna CE, Jung DH. A Novel Small Molecule Neurotrophin-3 Analogue Promotes Inner Ear Neurite Outgrowth and Synaptogenesis In vitro. Front Cell Neurosci 2021; 15:666706. [PMID: 34335184 PMCID: PMC8319950 DOI: 10.3389/fncel.2021.666706] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 06/18/2021] [Indexed: 11/15/2022] Open
Abstract
Sensorineural hearing loss is irreversible and is associated with the loss of spiral ganglion neurons (SGNs) and sensory hair cells within the inner ear. Improving spiral ganglion neuron (SGN) survival, neurite outgrowth, and synaptogenesis could lead to significant gains for hearing-impaired patients. There has therefore been intense interest in the use of neurotrophic factors in the inner ear to promote both survival of SGNs and re-wiring of sensory hair cells by surviving SGNs. Neurotrophin-3 (NT-3) and brain-derived neurotrophic factor (BDNF) represent the primary neurotrophins in the inner ear during development and throughout adulthood, and have demonstrated potential for SGN survival and neurite outgrowth. We have pioneered a hybrid molecule approach to maximize SGN stimulation in vivo, in which small molecule analogues of neurotrophins are linked to bisphosphonates, which in turn bind to cochlear bone. We have previously shown that a small molecule BDNF analogue coupled to risedronate binds to bone matrix and promotes SGN neurite outgrowth and synaptogenesis in vitro. Because NT-3 has been shown in a variety of contexts to have a greater regenerative capacity in the cochlea than BDNF, we sought to develop a similar approach for NT-3. 1Aa is a small molecule analogue of NT-3 that has been shown to activate cells through TrkC, the NT-3 receptor, although its activity on SGNs has not previously been described. Herein we describe the design and synthesis of 1Aa and a covalent conjugate of 1Aa with risedronate, Ris-1Aa. We demonstrate that both 1Aa and Ris-1Aa stimulate neurite outgrowth in SGN cultures at a significantly higher level compared to controls. Ris-1Aa maintained its neurotrophic activity when bound to hydroxyapatite, the primary mineral component of bone. Both 1Aa and Ris-1Aa promote significant synaptic regeneration in cochlear explant cultures, and both 1Aa and Ris-1Aa appear to act at least partly through TrkC. Our results provide the first evidence that a small molecule analogue of NT-3 can stimulate SGNs and promote regeneration of synapses between SGNs and inner hair cells. Our findings support the promise of hydroxyapatite-targeting bisphosphonate conjugation as a novel strategy to deliver neurotrophic agents to SGNs encased within cochlear bone.
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Affiliation(s)
- Judith S Kempfle
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States.,Department of Otolaryngology, University Medical Center Tübingen, Tübingen, Germany
| | - Marlon V Duro
- Department of Chemistry, University of Southern California, Los Angeles, CA, United States
| | - Andrea Zhang
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States
| | - Carolina D Amador
- Department of Chemistry, University of Southern California, Los Angeles, CA, United States
| | - Richard Kuang
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States
| | - Ryan Lu
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States
| | - Boris A Kashemirov
- Department of Chemistry, University of Southern California, Los Angeles, CA, United States
| | - Albert S Edge
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States
| | - Charles E McKenna
- Department of Chemistry, University of Southern California, Los Angeles, CA, United States
| | - David H Jung
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States
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Zhang C, Li Q, Chen M, Lu T, Min S, Li S. The role of oxidative stress in the susceptibility of noise-impaired cochleae to synaptic loss induced by intracochlear electrical stimulation. Neuropharmacology 2021; 196:108707. [PMID: 34246683 DOI: 10.1016/j.neuropharm.2021.108707] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 06/15/2021] [Accepted: 07/06/2021] [Indexed: 11/20/2022]
Abstract
Intracochlear electrical stimulation (ES) generated by cochlear implants (CIs) is used to activate auditory nerves to restore hearing perception in deaf subjects and those with residual hearing who use electroacoustic stimulation (EAS) technology. Approximately 1/3 of EAS recipients experience loss of residual hearing a few months after ES activation, but the underlying mechanism is unknown. Clinical evidence indicates that the loss is related to the previous history of noise-induced hearing loss (NIHL). In this report, we investigated the impact of intracochlear ES on oxidative stress levels and synaptic counts in inner hair cells (IHCs) of the apical, middle and basal regions of guinea pigs with normal hearing (NH) and NIHL. Our results demonstrated that intracochlear ES with an intensity of 6 dB above the thresholds of electrically evoked compound action potentials (ECAPs) could induce the elevation of oxidative stress levels, resulting in a loss of IHC synapses near the electrodes in the basal and middle regions of the NH cochleae. Furthermore, the apical region of cochleae with NIHL were more susceptible to synaptic loss induced by relatively low-intensity ES than that of NH cochleae, resulting from the additional elevation of oxidative stress levels and the reduced antioxidant capability throughout the whole cochlea.
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Affiliation(s)
- Chen Zhang
- Department of Otolaryngology - Head and Neck Surgery, Eye & ENT Hospital of Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Shanghai, China
| | - Qiang Li
- Department of Otolaryngology - Head and Neck Surgery, Eye & ENT Hospital of Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Shanghai, China
| | - Min Chen
- Department of Otolaryngology - Head and Neck Surgery, Eye & ENT Hospital of Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Shanghai, China
| | - Tianhao Lu
- Department of Otolaryngology - Head and Neck Surgery, Eye & ENT Hospital of Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Shanghai, China
| | - Shiyao Min
- Department of Otolaryngology - Head and Neck Surgery, Eye & ENT Hospital of Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Shanghai, China
| | - Shufeng Li
- Department of Otolaryngology - Head and Neck Surgery, Eye & ENT Hospital of Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Shanghai, China.
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Noise-Induced Hearing Loss: Updates on Molecular Targets and Potential Interventions. Neural Plast 2021; 2021:4784385. [PMID: 34306060 PMCID: PMC8279877 DOI: 10.1155/2021/4784385] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 06/12/2021] [Indexed: 12/18/2022] Open
Abstract
Noise overexposure leads to hair cell loss, synaptic ribbon reduction, and auditory nerve deterioration, resulting in transient or permanent hearing loss depending on the exposure severity. Oxidative stress, inflammation, calcium overload, glutamate excitotoxicity, and energy metabolism disturbance are the main contributors to noise-induced hearing loss (NIHL) up to now. Gene variations are also identified as NIHL related. Glucocorticoid is the only approved medication for NIHL treatment. New pharmaceuticals targeting oxidative stress, inflammation, or noise-induced neuropathy are emerging, highlighted by the nanoparticle-based drug delivery system. Given the complexity of the pathogenesis behind NIHL, deeper and more comprehensive studies still need to be fulfilled.
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Kim YG, Bak MS, Kim A, Kim Y, Chae YC, Kim YL, Chun YS, An JY, Seo SB, Kim SJ, Lee YS. Kdm3b haploinsufficiency impairs the consolidation of cerebellum-dependent motor memory in mice. Mol Brain 2021; 14:106. [PMID: 34217333 PMCID: PMC8254933 DOI: 10.1186/s13041-021-00815-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/16/2021] [Indexed: 11/10/2022] Open
Abstract
Histone modifications are a key mechanism underlying the epigenetic regulation of gene expression, which is critically involved in the consolidation of multiple forms of memory. However, the roles of histone modifications in cerebellum-dependent motor learning and memory are not well understood. To test whether changes in histone methylation are involved in cerebellar learning, we used heterozygous Kdm3b knockout (Kdm3b+/-) mice, which show reduced lysine 9 on histone 3 (H3K9) demethylase activity. H3K9 di-methylation is significantly increased selectively in the granule cell layer of the cerebellum of Kdm3b+/- mice. In the cerebellum-dependent optokinetic response (OKR) learning, Kdm3b+/- mice show deficits in memory consolidation, whereas they are normal in basal oculomotor performance and OKR acquisition. In addition, RNA-seq analyses revealed that the expression levels of several plasticity-related genes were altered in the mutant cerebellum. Our study suggests that active regulation of histone methylation is critical for the consolidation of cerebellar motor memory.
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Affiliation(s)
- Yong Gyu Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Korea
| | - Myeong Seong Bak
- Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Korea
| | - Ahbin Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Korea
| | - Yujin Kim
- Department of Biosystems and Biomedical Sciences, College of Health Sciences, Korea University, Seoul, 02841, Korea
- Department of Integrated Biomedical and Life Sciences, College of Health Sciences, Korea University, Seoul, Korea
| | - Yun-Cheol Chae
- Department of Life Science, College of Natural Science, Chung-Ang University, Seoul, 06974, Korea
| | - Ye Lee Kim
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Korea
- Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, 03080, Korea
| | - Yang-Sook Chun
- Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Korea
- Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, 03080, Korea
| | - Joon-Yong An
- Department of Biosystems and Biomedical Sciences, College of Health Sciences, Korea University, Seoul, 02841, Korea
- Department of Integrated Biomedical and Life Sciences, College of Health Sciences, Korea University, Seoul, Korea
| | - Sang-Beom Seo
- Department of Life Science, College of Natural Science, Chung-Ang University, Seoul, 06974, Korea
| | - Sang Jeong Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, Korea.
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Korea.
- Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, 03080, Korea.
| | - Yong-Seok Lee
- Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, Korea.
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Korea.
- Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, 03080, Korea.
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Disruption of the autism-related gene Pak1 causes stereocilia disorganization, hair cell loss, and deafness in mice. J Genet Genomics 2021; 48:324-332. [PMID: 34049799 DOI: 10.1016/j.jgg.2021.03.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/18/2021] [Accepted: 03/12/2021] [Indexed: 01/06/2023]
Abstract
Several clinical studies have reported that hearing loss is correlated with autism in children. However, little is known about the underlying mechanism between hearing loss and autism. p21-activated kinases (PAKs) are a family of serine/threonine kinases that can be activated by multiple signaling molecules, particularly the Rho family of small GTPases. Previous studies have shown that Pak1 mutations are associated with autism. In the present study, we take advantage of Pak1 knockout (Pak1-/-) mice to investigate the role of PAK1 in hearing function. We find that PAK1 is highly expressed in the postnatal mouse cochlea and that PAK1 deficiency leads to hair cell (HC) apoptosis and severe hearing loss. Further investigation indicates that PAK1 deficiency downregulates the phosphorylation of cofilin and ezrin-radixin-moesin and the expression of βII-spectrin, which further decreases the HC synapse density in the basal turn of cochlea and disorganized the HC stereocilia in all three turns of cochlea in Pak1-/- mice. Overall, our work demonstrates that the autism-related gene Pak1 plays a crucial role in hearing function. As the first candidate gene linking autism and hearing loss, Pak1 may serve as a potential target for the clinical diagnosis of autism-related hearing loss.
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Stabenau KA, Zimmermann MT, Mathison A, Zeighami A, Samuels TL, Chun RH, Papsin BC, McCormick ME, Johnston N, Kerschner JE. RNA Sequencing and Pathways Analyses of Middle Ear Epithelia From Patients With Otitis Media. Laryngoscope 2021; 131:2590-2597. [PMID: 33844317 DOI: 10.1002/lary.29551] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/04/2021] [Accepted: 03/23/2021] [Indexed: 01/24/2023]
Abstract
OBJECTIVES Otitis media (OM) is the most common pediatric diagnosis in the United States. However, our understanding of the molecular pathogenesis of OM remains relatively poor. Investigation of molecular pathways involved in OM may improve the understanding of this disease process and elucidate novel therapeutic targets. In this study, RNA sequencing (RNA-Seq) was used to discern cellular changes associated with OME compared to healthy middle ear epithelium (MEE). STUDY DESIGN Ex vivo case-control translational. METHODS Middle ear epithelia was collected from five pediatric patients diagnosed with OME undergoing tympanostomy tube placement and five otherwise healthy pediatric patients undergoing cochlear implantation. Specimens underwent RNA-Seq and pathways analyses. RESULTS A total of 1,292 genes exhibited differential expression in MEE from OME patients compared to controls including genes involved in inflammation, immune response to bacterial OM pathogens, mucociliary clearance, regulation of proliferation and transformation, and auditory cell differentiation. Top networks identified in OME were organismal injury and abnormalities, cell morphology, and auditory disease. Top Ingenuity canonical pathways identified were axonal guidance signaling, which contains genes associated with auditory development and disease and nicotine degradation II and III pathways. Associated upstream regulators included β-estradiol, dexamethasone, and G-protein-coupled estrogen receptor-1 (GPER1), which are associated with otoprotection or inflammation during insult. CONCLUSIONS RNA-Seq demonstrates differential gene expression in MEE from patients with OME compared to healthy controls with important implications for infection susceptibility, hearing loss, and a role for tobacco exposure in the development and/or severity of OME in pediatric patients. LEVEL OF EVIDENCE 4 Laryngoscope, 2021.
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Affiliation(s)
- Kaleigh A Stabenau
- Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A
| | - Michael T Zimmermann
- Bioinformatics Research and Development Laboratory, Genomic Sciences and Precision Medicine Center, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A.,Clinical and Translational Science Institute, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A
| | - Angela Mathison
- Bioinformatics Research and Development Laboratory, Genomic Sciences and Precision Medicine Center, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A
| | - Atefeh Zeighami
- Bioinformatics Research and Development Laboratory, Genomic Sciences and Precision Medicine Center, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A
| | - Tina L Samuels
- Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A
| | - Robert H Chun
- Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A
| | - Blake C Papsin
- Archie's Cochlear Implant Laboratory, Department of Otolaryngology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Michael E McCormick
- Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A
| | - Nikki Johnston
- Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A.,Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A
| | - Joseph E Kerschner
- Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A
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47
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Zu M, Guo WW, Cong T, Ji F, Zhang SL, Zhang Y, Song X, Sun W, He DZZ, Shi WG, Yang SM. SCN11A gene deletion causes sensorineural hearing loss by impairing the ribbon synapses and auditory nerves. BMC Neurosci 2021; 22:18. [PMID: 33752606 PMCID: PMC7986359 DOI: 10.1186/s12868-021-00613-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 01/20/2021] [Indexed: 11/10/2022] Open
Abstract
Background The SCN11A gene, encoded Nav1.9 TTX resistant sodium channels, is a main effector in peripheral inflammation related pain in nociceptive neurons. The role of SCN11A gene in the auditory system has not been well characterized. We therefore examined the expression of SCN11A in the murine cochlea, the morphological and physiological features of Nav1.9 knockout (KO) ICR mice. Results Nav1.9 expression was found in the primary afferent endings beneath the inner hair cells (IHCs). The relative quantitative expression of Nav1.9 mRNA in modiolus of wild-type (WT) mice remains unchanged from P0 to P60. The number of presynaptic CtBP2 puncta in Nav1.9 KO mice was significantly lower than WT. In addition, the number of SGNs in Nav1.9 KO mice was also less than WT in the basal turn, but not in the apical and middle turns. There was no lesion in the somas and stereocilia of hair cells in Nav1.9 KO mice. Furthermore, Nav1.9 KO mice showed higher and progressive elevated ABR threshold at 16 kHz, and a significant increase in CAP thresholds. Conclusions These data suggest a role of Nav1.9 in regulating the function of ribbon synapses and the auditory nerves. The impairment induced by Nav1.9 gene deletion mimics the characters of cochlear synaptopathy.
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Affiliation(s)
- Mian Zu
- College of Otolaryngology Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Science, Ministry of Education, Beijing, China.,Beijing Key Lab of Hearing Impairment for Prevention and Treatment, Beijing, China
| | - Wei-Wei Guo
- College of Otolaryngology Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Science, Ministry of Education, Beijing, China.,Beijing Key Lab of Hearing Impairment for Prevention and Treatment, Beijing, China
| | - Tao Cong
- College of Otolaryngology Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Science, Ministry of Education, Beijing, China.,Beijing Key Lab of Hearing Impairment for Prevention and Treatment, Beijing, China
| | - Fei Ji
- College of Otolaryngology Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Science, Ministry of Education, Beijing, China.,Beijing Key Lab of Hearing Impairment for Prevention and Treatment, Beijing, China
| | - Shi-Li Zhang
- Clinical Hearing Center of Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Yue Zhang
- College of Otolaryngology Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Science, Ministry of Education, Beijing, China.,Beijing Key Lab of Hearing Impairment for Prevention and Treatment, Beijing, China
| | - Xin Song
- College of Otolaryngology Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Science, Ministry of Education, Beijing, China.,Beijing Key Lab of Hearing Impairment for Prevention and Treatment, Beijing, China
| | - Wei Sun
- Department of Communicative Disorders and Sciences, Center for Hearing and Deafness, The State University of New York at Buffalo, Buffalo, NY, USA
| | - David Z Z He
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, NE, 68178, USA
| | - Wei-Guo Shi
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing, China.
| | - Shi-Ming Yang
- College of Otolaryngology Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China. .,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China. .,Key Lab of Hearing Science, Ministry of Education, Beijing, China. .,Beijing Key Lab of Hearing Impairment for Prevention and Treatment, Beijing, China.
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48
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Bankoti K, Generotti C, Hwa T, Wang L, O'Malley BW, Li D. Advances and challenges in adeno-associated viral inner-ear gene therapy for sensorineural hearing loss. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2021; 21:209-236. [PMID: 33850952 PMCID: PMC8010215 DOI: 10.1016/j.omtm.2021.03.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
There is growing attention and effort focused on treating the root cause of sensorineural hearing loss rather than managing associated secondary characteristic features. With recent substantial advances in understanding sensorineural hearing-loss mechanisms, gene delivery has emerged as a promising strategy for the biological treatment of hearing loss associated with genetic dysfunction. There are several successful and promising proof-of-principle examples of transgene deliveries in animal models; however, there remains substantial further progress to be made in these avenues before realizing their clinical application in humans. Herein, we review different aspects of development, ongoing preclinical studies, and challenges to the clinical transition of transgene delivery of the inner ear toward the restoration of lost auditory and vestibular function.
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Affiliation(s)
- Kamakshi Bankoti
- Department of Otorhinolaryngology, Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Charles Generotti
- Department of Otorhinolaryngology, Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Tiffany Hwa
- Department of Otorhinolaryngology, Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Lili Wang
- Department of Medicine, Gene Therapy Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Bert W O'Malley
- Department of Otorhinolaryngology, Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Daqing Li
- Department of Otorhinolaryngology, Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Kohrman DC, Borges BC, Cassinotti LR, Ji L, Corfas G. Axon-glia interactions in the ascending auditory system. Dev Neurobiol 2021; 81:546-567. [PMID: 33561889 DOI: 10.1002/dneu.22813] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 11/25/2020] [Accepted: 02/05/2021] [Indexed: 11/09/2022]
Abstract
The auditory system detects and encodes sound information with high precision to provide a high-fidelity representation of the environment and communication. In mammals, detection occurs in the peripheral sensory organ (the cochlea) containing specialized mechanosensory cells (hair cells) that initiate the conversion of sound-generated vibrations into action potentials in the auditory nerve. Neural activity in the auditory nerve encodes information regarding the intensity and frequency of sound stimuli, which is transmitted to the auditory cortex through the ascending neural pathways. Glial cells are critical for precise control of neural conduction and synaptic transmission throughout the pathway, allowing for the precise detection of the timing, frequency, and intensity of sound signals, including the sub-millisecond temporal fidelity is necessary for tasks such as sound localization, and in humans, for processing complex sounds including speech and music. In this review, we focus on glia and glia-like cells that interact with hair cells and neurons in the ascending auditory pathway and contribute to the development, maintenance, and modulation of neural circuits and transmission in the auditory system. We also discuss the molecular mechanisms of these interactions, their impact on hearing and on auditory dysfunction associated with pathologies of each cell type.
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Affiliation(s)
- David C Kohrman
- Department of Otolaryngology - Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
| | - Beatriz C Borges
- Department of Otolaryngology - Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
| | - Luis R Cassinotti
- Department of Otolaryngology - Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
| | - Lingchao Ji
- Department of Otolaryngology - Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
| | - Gabriel Corfas
- Department of Otolaryngology - Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
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50
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Fernandez KA, Watabe T, Tong M, Meng X, Tani K, Kujawa SG, Edge AS. Trk agonist drugs rescue noise-induced hidden hearing loss. JCI Insight 2021; 6:142572. [PMID: 33373328 PMCID: PMC7934864 DOI: 10.1172/jci.insight.142572] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 12/16/2020] [Indexed: 12/21/2022] Open
Abstract
TrkB agonist drugs are shown here to have a significant effect on the regeneration of afferent cochlear synapses after noise-induced synaptopathy. The effects were consistent with regeneration of cochlear synapses that we observed in vitro after synaptic loss due to kainic acid-induced glutamate toxicity and were elicited by administration of TrkB agonists, amitriptyline, and 7,8-dihydroxyflavone, directly into the cochlea via the posterior semicircular canal 48 hours after exposure to noise. Synaptic counts at the inner hair cell and wave 1 amplitudes in the auditory brainstem response (ABR) were partially restored 2 weeks after drug treatment. Effects of amitriptyline on wave 1 amplitude and afferent auditory synapse numbers in noise-exposed ears after systemic (as opposed to local) delivery were profound and long-lasting; synapses in the treated animals remained intact 1 year after the treatment. However, the effect of systemically delivered amitriptyline on synaptic rescue was dependent on dose and the time window of administration: it was only effective when given before noise exposure at the highest injected dose. The long-lasting effect and the efficacy of postexposure treatment indicate a potential broad application for the treatment of synaptopathy, which often goes undetected until well after the original damaging exposures.
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Affiliation(s)
- Katharine A Fernandez
- Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, Massachusetts, USA
| | - Takahisa Watabe
- Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, Massachusetts, USA
| | - Mingjie Tong
- Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, Massachusetts, USA
| | - Xiankai Meng
- Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, Massachusetts, USA
| | - Kohsuke Tani
- Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, Massachusetts, USA
| | - Sharon G Kujawa
- Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, Massachusetts, USA.,Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, Massachusetts, USA
| | - Albert Sb Edge
- Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, Massachusetts, USA.,Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, Massachusetts, USA.,Harvard Stem Cell Institute, Cambridge, Massachusetts, USA
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