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Jarysta A, Tadenev ALD, Day M, Krawchuk B, Low BE, Wiles MV, Tarchini B. Inhibitory G proteins play multiple roles to polarize sensory hair cell morphogenesis. eLife 2024; 12:RP88186. [PMID: 38651641 PMCID: PMC11037916 DOI: 10.7554/elife.88186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024] Open
Abstract
Inhibitory G alpha (GNAI or Gαi) proteins are critical for the polarized morphogenesis of sensory hair cells and for hearing. The extent and nature of their actual contributions remains unclear, however, as previous studies did not investigate all GNAI proteins and included non-physiological approaches. Pertussis toxin can downregulate functionally redundant GNAI1, GNAI2, GNAI3, and GNAO proteins, but may also induce unrelated defects. Here, we directly and systematically determine the role(s) of each individual GNAI protein in mouse auditory hair cells. GNAI2 and GNAI3 are similarly polarized at the hair cell apex with their binding partner G protein signaling modulator 2 (GPSM2), whereas GNAI1 and GNAO are not detected. In Gnai3 mutants, GNAI2 progressively fails to fully occupy the sub-cellular compartments where GNAI3 is missing. In contrast, GNAI3 can fully compensate for the loss of GNAI2 and is essential for hair bundle morphogenesis and auditory function. Simultaneous inactivation of Gnai2 and Gnai3 recapitulates for the first time two distinct types of defects only observed so far with pertussis toxin: (1) a delay or failure of the basal body to migrate off-center in prospective hair cells, and (2) a reversal in the orientation of some hair cell types. We conclude that GNAI proteins are critical for hair cells to break planar symmetry and to orient properly before GNAI2/3 regulate hair bundle morphogenesis with GPSM2.
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Affiliation(s)
| | | | - Matthew Day
- The Jackson LaboratoryBar HarborUnited States
| | | | | | | | - Basile Tarchini
- The Jackson LaboratoryBar HarborUnited States
- Tufts University School of MedicineBostonUnited States
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2
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Carlton AJ, Jeng JY, Grandi FC, De Faveri F, Amariutei AE, De Tomasi L, O'Connor A, Johnson SL, Furness DN, Brown SDM, Ceriani F, Bowl MR, Mustapha M, Marcotti W. BAI1 localizes AMPA receptors at the cochlear afferent post-synaptic density and is essential for hearing. Cell Rep 2024; 43:114025. [PMID: 38564333 DOI: 10.1016/j.celrep.2024.114025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 01/25/2024] [Accepted: 03/15/2024] [Indexed: 04/04/2024] Open
Abstract
Type I spiral ganglion neurons (SGNs) convey sound information to the central auditory pathway by forming synapses with inner hair cells (IHCs) in the mammalian cochlea. The molecular mechanisms regulating the formation of the post-synaptic density (PSD) in the SGN afferent terminals are still unclear. Here, we demonstrate that brain-specific angiogenesis inhibitor 1 (BAI1) is required for the clustering of AMPA receptors GluR2-4 (glutamate receptors 2-4) at the PSD. Adult Bai1-deficient mice have functional IHCs but fail to transmit information to the SGNs, leading to highly raised hearing thresholds. Despite the almost complete absence of AMPA receptor subunits, the SGN fibers innervating the IHCs do not degenerate. Furthermore, we show that AMPA receptors are still expressed in the cochlea of Bai1-deficient mice, highlighting a role for BAI1 in trafficking or anchoring GluR2-4 to the PSDs. These findings identify molecular and functional mechanisms required for sound encoding at cochlear ribbon synapses.
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Affiliation(s)
- Adam J Carlton
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Jing-Yi Jeng
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Fiorella C Grandi
- Sorbonne Université, INSERM, Institute de Myologie, Centre de Recherche en Myologie, 75013 Paris, France
| | | | - Ana E Amariutei
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Lara De Tomasi
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Andrew O'Connor
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Stuart L Johnson
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK; Neuroscience Institute, University of Sheffield, Sheffield S10 2TN, UK
| | - David N Furness
- School of Life Sciences, Keele University, Keele ST5 5BG, UK
| | - Steve D M Brown
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Federico Ceriani
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Michael R Bowl
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Mirna Mustapha
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK; Neuroscience Institute, University of Sheffield, Sheffield S10 2TN, UK
| | - Walter Marcotti
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK; Neuroscience Institute, University of Sheffield, Sheffield S10 2TN, UK.
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3
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Beaulieu MO, Thomas ED, Raible DW. Transdifferentiation is uncoupled from progenitor pool expansion during hair cell regeneration in the zebrafish inner ear. bioRxiv 2024:2024.04.09.588777. [PMID: 38645220 PMCID: PMC11030336 DOI: 10.1101/2024.04.09.588777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Death of mechanosensory hair cells in the inner ear is a common cause of auditory and vestibular impairment in mammals, which have a limited ability to regrow these cells after damage. In contrast, non-mammalian vertebrates including zebrafish can robustly regenerate hair cells following severe organ damage. The zebrafish inner ear provides an understudied model system for understanding hair cell regeneration in organs that are highly conserved with their mammalian counterparts. Here we quantitatively examine hair cell addition during growth and regeneration of the larval zebrafish inner ear. We used a genetically encoded ablation method to induce hair cell death and observed gradual regeneration with correct spatial patterning over two weeks following ablation. Supporting cells, which surround and are a source of new hair cells, divide in response to hair cell ablation, expanding the possible progenitor pool. In parallel, nascent hair cells arise from direct transdifferentiation of progenitor pool cells uncoupled from progenitor division. These findings reveal a previously unrecognized mechanism of hair cell regeneration with implications for how hair cells may be encouraged to regenerate in the mammalian ear.
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Affiliation(s)
- Marielle O. Beaulieu
- Molecular and Cellular Biology Graduate Program, Seattle, WA
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology - Head and Neck Surgery, Seattle, WA
| | - Eric D. Thomas
- Neuroscience Graduate Program, Seattle, WA
- Department of Biological Structure University of Washington, Seattle, WA
| | - David W. Raible
- Molecular and Cellular Biology Graduate Program, Seattle, WA
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology - Head and Neck Surgery, Seattle, WA
- Neuroscience Graduate Program, Seattle, WA
- Department of Biological Structure University of Washington, Seattle, WA
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4
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Ratzan EM, Lee J, Madison MA, Zhu H, Zhou W, Géléoc GSG, Holt JR. TMC function, dysfunction, and restoration in mouse vestibular organs. Front Neurol 2024; 15:1356614. [PMID: 38638308 PMCID: PMC11024474 DOI: 10.3389/fneur.2024.1356614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 03/18/2024] [Indexed: 04/20/2024] Open
Abstract
Tmc1 and Tmc2 are essential pore-forming subunits of mechanosensory transduction channels localized to the tips of stereovilli in auditory and vestibular hair cells of the inner ear. To investigate expression and function of Tmc1 and Tmc2 in vestibular organs, we used quantitative polymerase chain reaction (qPCR), fluorescence in situ hybridization - hairpin chain reaction (FISH-HCR), immunostaining, FM1-43 uptake and we measured vestibular evoked potentials (VsEPs) and vestibular ocular reflexes (VORs). We found that Tmc1 and Tmc2 showed dynamic developmental changes, differences in regional expression patterns, and overall expression levels which differed between the utricle and saccule. These underlying changes contributed to unanticipated phenotypic loss of VsEPs and VORs in Tmc1 KO mice. In contrast, Tmc2 KO mice retained VsEPs despite the loss of the calcium buffering protein calretinin, a characteristic biomarker of mature striolar calyx-only afferents. Lastly, we found that neonatal Tmc1 gene replacement therapy is sufficient to restore VsEP in Tmc1 KO mice for up to six months post-injection.
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Affiliation(s)
- Evan M. Ratzan
- Department of Otolaryngology, F.M. Kirby Neurobiology Center, Boston Children’s Hospital and Harvard Medical School, Boston, MA, United States
| | - John Lee
- Department of Otolaryngology, F.M. Kirby Neurobiology Center, Boston Children’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Margot A. Madison
- Department of Otolaryngology, F.M. Kirby Neurobiology Center, Boston Children’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Hong Zhu
- Department of Otolaryngology - Head and Neck Surgery, University of Mississippi Medical Center, Jackson, MS, United States
| | - Wu Zhou
- Department of Otolaryngology - Head and Neck Surgery, University of Mississippi Medical Center, Jackson, MS, United States
| | - Gwenaëlle S. G. Géléoc
- Department of Otolaryngology, F.M. Kirby Neurobiology Center, Boston Children’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Jeffrey R. Holt
- Department of Otolaryngology, F.M. Kirby Neurobiology Center, Boston Children’s Hospital and Harvard Medical School, Boston, MA, United States
- Department of Neurology, Boston Children’s Hospital and Harvard Medical School, Boston, MA, United States
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5
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Slika E, Fuchs PA. Genetic tools for studying cochlear inhibition. Front Cell Neurosci 2024; 18:1372948. [PMID: 38560293 PMCID: PMC10978695 DOI: 10.3389/fncel.2024.1372948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 02/28/2024] [Indexed: 04/04/2024] Open
Abstract
Efferent feedback to the mammalian cochlea includes cholinergic medial olivocochlear neurons (MOCs) that release ACh to hyperpolarize and shunt the voltage change that drives electromotility of outer hair cells (OHCs). Via brainstem connectivity, MOCs are activated by sound in a frequency- and intensity-dependent manner, thereby reducing the amplification of cochlear vibration provided by OHC electromotility. Among other roles, this efferent feedback protects the cochlea from acoustic trauma. Lesion studies, as well as a variety of genetic mouse models, support the hypothesis of efferent protection from acoustic trauma. Genetic knockout and gain-of-function knockin of the unique α9α10-containing nicotinic acetylcholine receptor (nAChR) in hair cells show that acoustic protection correlates with the efficacy of cholinergic inhibition of OHCs. This protective effect was replicated by viral transduction of the gain-of-function α9L9'T nAChR into α9-knockout mice. Continued progress with "efferent gene therapy" will require a reliable method for visualizing nAChR expression in cochlear hair cells. To that end, mice expressing HA-tagged α9 or α10 nAChRs were generated using CRISPR technology. This progress will facilitate continued study of the hair cell nAChR as a therapeutic target to prevent hearing loss and potentially to ameliorate associated pathologies such as hyperacusis.
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Affiliation(s)
| | - Paul Albert Fuchs
- The Center for Hearing and Balance, Otolaryngology-Head and Neck Surgery, Johns Hopkins, University School of Medicine Baltimore, Baltimore, MD, United States
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6
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Jáuregui EJ, Scheinman KL, Bibriesca Mejia IK, Pruett L, Zaini H, Finkbeiner C, Phillips JA, Gantz JA, Nguyen TB, Phillips JO, Stone JS. Sensorineural correlates of failed functional recovery after natural regeneration of vestibular hair cells in adult mice. Front Neurol 2024; 15:1322647. [PMID: 38523617 PMCID: PMC10960365 DOI: 10.3389/fneur.2024.1322647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 02/23/2024] [Indexed: 03/26/2024] Open
Abstract
Vestibular hair cells (HCs) are mechanoreceptors that sense head motions by modulating the firing rate of vestibular ganglion neurons (VGNs), whose central processes project to vestibular nucleus neurons (VNNs) and cerebellar neurons. We explored vestibular function after HC destruction in adult Pou4f3+/DTR (DTR) mice, in which injections of high-dose (50 ng/g) diphtheria toxin (DT) destroyed most vestibular HCs within 2 weeks. At that time, DTR mice had lost the horizontal vestibulo-ocular reflex (aVORH), and their VNNs failed to upregulate nuclear cFos expression in response to a vestibular stimulus (centrifugation). Five months later, 21 and 14% of HCs were regenerated in utricles and horizontal ampullae, respectively. The vast majority of HCs present were type II. This degree of HC regeneration did not restore the aVORH or centrifugation-evoked cFos expression in VNNs. The failure to regain vestibular pathway function was not due to degeneration of VGNs or VNNs because normal neuron numbers were maintained after HC destruction. Furthermore, sinusoidal galvanic stimulation at the mastoid process evoked cFos protein expression in VNNs, indicating that VGNs were able to regulate VNN activity after HC loss. aVORH and cFos responses in VNNs were robust after low-dose (25 ng/g) DT, which compared to high-dose DT resulted in a similar degree of type II HC death and regeneration but spared more type I HCs in both organs. These findings demonstrate that having more type I HCs is correlated with stronger responses to vestibular stimulation and suggest that regenerating type I HCs may improve vestibular function after HC loss.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Jennifer S. Stone
- Department of Otolaryngology-Head and Neck Surgery and the Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA, United States
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7
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Schilder AGM, Wolpert S, Saeed S, Middelink LM, Edge ASB, Blackshaw H, Pastiadis K, Bibas AG. A phase I/IIa safety and efficacy trial of intratympanic gamma-secretase inhibitor as a regenerative drug treatment for sensorineural hearing loss. Nat Commun 2024; 15:1896. [PMID: 38429256 PMCID: PMC10907343 DOI: 10.1038/s41467-024-45784-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 02/01/2024] [Indexed: 03/03/2024] Open
Abstract
Inhibition of Notch signalling with a gamma-secretase inhibitor (GSI) induces mammalian hair cell regeneration and partial hearing restoration. In this proof-of-concept Phase I/IIa multiple-ascending dose open-label trial (ISRCTN59733689), adults with mild-moderate sensorineural hearing loss received 3 intratympanic injections of GSI LY3056480, in 1 ear over 2 weeks. Phase I primary outcome was safety and tolerability. Phase lla primary outcome was change from baseline to 12 weeks in average pure-tone air conduction threshold across 2,4,8 kHz. Secondary outcomes included this outcome at 6 weeks and change from baseline to 6 and 12 weeks in pure-tone thresholds at individual frequencies, speech reception thresholds (SRTs), Distortion Product Otoacoustic Emissions (DPOAE) amplitudes, Signal to Noise Ratios (SNRs) and distribution of categories normal, present-abnormal, absent and Hearing Handicap Inventory for Adults/Elderly (HHIA/E). In Phase I (N = 15, 1 site) there were no severe nor serious adverse events. In Phase IIa (N = 44, 3 sites) the average pure-tone threshold across 2,4,8 kHz did not change from baseline to 6 and 12 weeks (estimated change -0.87 dB; 95% CI -2.37 to 0.63; P = 0.252 and -0.46 dB; 95% CI -1.94 to 1.03; P = 0.545, respectively), nor did the means of secondary measures. DPOAE amplitudes, SNRs and distribution of categories did not change from baseline to 6 and 12 weeks, nor did SRTs and HHIA/E scores. Intratympanic delivery of LY3056480 is safe and well-tolerated; the trial's primary endpoint was not met.
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Affiliation(s)
- Anne G M Schilder
- National Institute for Health Research University College London Hospitals Biomedical Research Centre, London, UK
- Ear Institute, University College London, London, UK
- Royal National ENT and Eastman Dental Hospitals, University College London Hospitals Trust, London, UK
| | - Stephan Wolpert
- Department of Otolaryngology, Head and Neck Surgery, University of Tübingen, Tübingen, Germany.
| | - Shakeel Saeed
- National Institute for Health Research University College London Hospitals Biomedical Research Centre, London, UK
- Ear Institute, University College London, London, UK
- Royal National ENT and Eastman Dental Hospitals, University College London Hospitals Trust, London, UK
| | | | - Albert S B Edge
- Department of Otolaryngology, Harvard Medical School, Boston, USA
| | - Helen Blackshaw
- National Institute for Health Research University College London Hospitals Biomedical Research Centre, London, UK
- Ear Institute, University College London, London, UK
| | - Kostas Pastiadis
- 1st Department of Otolaryngology, Hippocration Hospital Athens, National & Kapodistrian University of Athens, Athens, Greece
| | - Athanasios G Bibas
- 1st Department of Otolaryngology, Hippocration Hospital Athens, National & Kapodistrian University of Athens, Athens, Greece
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8
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Jukic A, Lei Z, Cebul ER, Pinter K, Mosqueda N, David S, Tarchini B, Kindt K. Presynaptic Nrxn3 is essential for ribbon-synapse assembly in hair cells. bioRxiv 2024:2024.02.14.580267. [PMID: 38410471 PMCID: PMC10896334 DOI: 10.1101/2024.02.14.580267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Hair cells of the inner ear rely on specialized ribbon synapses to transmit sensory information to the central nervous system. The molecules required to assemble these synapses are not fully understood. We show that Nrxn3, a presynaptic adhesion molecule, is critical for ribbon-synapse assembly in hair cells. In both mouse and zebrafish models, loss of Nrxn3 results in significantly fewer intact ribbon synapses. In zebrafish we demonstrate that a 60% loss of synapses in nrxn3 mutants dramatically reduces both presynaptic responses in hair cells and postsynaptic responses in afferent neurons. Despite a reduction in synapse function in this model, we find no deficits in the acoustic startle response, a behavior reliant on these synapses. Overall, this work demonstrates that Nrxn3 is a critical and conserved molecule required to assemble ribbon synapses. Understanding how ribbon synapses assemble is a key step towards generating novel therapies to treat forms of age-related and noise-induced hearing loss that occur due to loss of ribbon synapses.
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Affiliation(s)
- Alma Jukic
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | - Zhengchang Lei
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | - Elizabeth R Cebul
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | - Katherine Pinter
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | - Natalie Mosqueda
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | - Sandeep David
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
| | | | - Katie Kindt
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, Bethesda, MD, 20892, USA
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9
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Lee JH, Perez-Flores MC, Park S, Kim HJ, Chen Y, Kang M, Kersigo J, Choi J, Thai PN, Woltz RL, Perez-Flores DC, Perkins G, Sihn CR, Trinh P, Zhang XD, Sirish P, Dong Y, Feng WW, Pessah IN, Dixon RE, Sokolowski B, Fritzsch B, Chiamvimonvat N, Yamoah EN. The Piezo channel is a mechano-sensitive complex component in the mammalian inner ear hair cell. Nat Commun 2024; 15:526. [PMID: 38228630 PMCID: PMC10791687 DOI: 10.1038/s41467-023-44230-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 12/04/2023] [Indexed: 01/18/2024] Open
Abstract
The inner ear is the hub where hair cells (HCs) transduce sound, gravity, and head acceleration stimuli to the brain. Hearing and balance rely on mechanosensation, the fastest sensory signals transmitted to the brain. The mechanoelectrical transducer (MET) channel is the entryway for the sound-balance-brain interface, but the channel-complex composition is not entirely known. Here, we report that the mouse utilizes Piezo1 (Pz1) and Piezo2 (Pz2) isoforms as MET-complex components. The Pz channels, expressed in HC stereocilia, and cell lines are co-localized and co-assembled with MET complex partners. Mice expressing non-functional Pz1 and Pz2 at the ROSA26 locus have impaired auditory and vestibular traits that can only be explained if the Pzs are integral to the MET complex. We suggest that Pz subunits constitute part of the MET complex and that interactions with other MET complex components yield functional MET units to generate HC MET currents.
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Affiliation(s)
- Jeong Han Lee
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Maria C Perez-Flores
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Seojin Park
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
- Prestige Biopharma, 11-12F, 44, Myongjigukje7-ro, Gangseo-gu, Busan, 67264, South Korea
| | - Hyo Jeong Kim
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Yingying Chen
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Mincheol Kang
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
- Prestige Biopharma, 11-12F, 44, Myongjigukje7-ro, Gangseo-gu, Busan, 67264, South Korea
| | | | - Jinsil Choi
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Phung N Thai
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of California, Davis, CA, 95616, USA
| | - Ryan L Woltz
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of California, Davis, CA, 95616, USA
| | | | - Guy Perkins
- National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, CA, 92093, USA
| | - Choong-Ryoul Sihn
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Pauline Trinh
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of California, Davis, CA, 95616, USA
| | - Xiao-Dong Zhang
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of California, Davis, CA, 95616, USA
| | - Padmini Sirish
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of California, Davis, CA, 95616, USA
| | - Yao Dong
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, 1089 VM3B, Davis, CA, 95616, USA
| | - Wayne Wei Feng
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, 1089 VM3B, Davis, CA, 95616, USA
| | - Isaac N Pessah
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, 1089 VM3B, Davis, CA, 95616, USA
| | - Rose E Dixon
- Department of Physiology & Membrane Biology, Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA
| | - Bernd Sokolowski
- Department of Otolaryngology-Head and Neck Surgery, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA
| | - Bernd Fritzsch
- Department of Biology, University of Iowa, Iowa City, IA, USA
| | - Nipavan Chiamvimonvat
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of California, Davis, CA, 95616, USA
- VA Northern California Healthcare System, Sacramento, USA
| | - Ebenezer N Yamoah
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA.
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10
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Yoon HS, Hyun KT, Hong S, Park S, Han E, Baek HW, Lee YK, Lim KH, Rah YC, Choi J. Exploring Embryo-Ototoxic Effects: Insights into Deodorant-Induced Hair Cell Damage in Zebrafish. Int J Mol Sci 2024; 25:948. [PMID: 38256022 PMCID: PMC10815967 DOI: 10.3390/ijms25020948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 01/06/2024] [Accepted: 01/10/2024] [Indexed: 01/24/2024] Open
Abstract
Our study investigated the embryo-ototoxic effects of deodorant2 (DA2) on zebrafish embryos, which serve as valuable model organisms due to genetic and physiological similarities to humans. We focused on understanding DA2's impact on zebrafish hair cells, which are vital for sensory perception and balance regulation. DA2, provided by the Ministry of Environment, Republic of Korea, was used at 460 μg/mL in dimethyl sulfoxide (DMSO), with a 0.43% DMSO solvent control group. Three experiments, each using 10 zebrafish specimens from each group, showed an initial 13% hair cell count reduction in the DA2-exposed group. Subsequent experiments demonstrated reductions of 37% and 22%, each with one mortality case. Statistical analysis revealed a significant 24% hair cell count reduction in the DA2-exposed group. We also assessed DA2's impact on zebrafish behavior. Although not statistically significant, differences in distances traveled (0.33-0.39, 95% confidence interval: -0.46-1.1, p = 0.2033) and latencies (-0.016-0.018, 95% confidence interval: -0.052-0.021, p = 0.1917) hinted at negative effects. These results highlight DA2's ototoxic properties affecting zebrafish auditory systems and behavior. Further investigation into DA2's effects on aquatic organisms and potential mitigation strategies are essential. These findings contribute to understanding DA2's safety profile, benefiting aquatic ecosystems and human health assessments.
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Affiliation(s)
- Hee Soo Yoon
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Ansan Hospital, Ansan 15355, Republic of Korea; (H.S.Y.); (K.T.H.); (S.H.); (S.P.); (E.H.); (H.w.B.); (Y.K.L.); (K.H.L.); (Y.C.R.)
| | - Kyung Tae Hyun
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Ansan Hospital, Ansan 15355, Republic of Korea; (H.S.Y.); (K.T.H.); (S.H.); (S.P.); (E.H.); (H.w.B.); (Y.K.L.); (K.H.L.); (Y.C.R.)
| | - Sumin Hong
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Ansan Hospital, Ansan 15355, Republic of Korea; (H.S.Y.); (K.T.H.); (S.H.); (S.P.); (E.H.); (H.w.B.); (Y.K.L.); (K.H.L.); (Y.C.R.)
| | - Saemi Park
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Ansan Hospital, Ansan 15355, Republic of Korea; (H.S.Y.); (K.T.H.); (S.H.); (S.P.); (E.H.); (H.w.B.); (Y.K.L.); (K.H.L.); (Y.C.R.)
| | - Eunjung Han
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Ansan Hospital, Ansan 15355, Republic of Korea; (H.S.Y.); (K.T.H.); (S.H.); (S.P.); (E.H.); (H.w.B.); (Y.K.L.); (K.H.L.); (Y.C.R.)
| | - Hyun woo Baek
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Ansan Hospital, Ansan 15355, Republic of Korea; (H.S.Y.); (K.T.H.); (S.H.); (S.P.); (E.H.); (H.w.B.); (Y.K.L.); (K.H.L.); (Y.C.R.)
| | - Yun Kyoung Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Ansan Hospital, Ansan 15355, Republic of Korea; (H.S.Y.); (K.T.H.); (S.H.); (S.P.); (E.H.); (H.w.B.); (Y.K.L.); (K.H.L.); (Y.C.R.)
- Biomedical Research Center, Korea University College of Medicine, Ansan Hospital, Ansan 15355, Republic of Korea
| | - Kang Hyeon Lim
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Ansan Hospital, Ansan 15355, Republic of Korea; (H.S.Y.); (K.T.H.); (S.H.); (S.P.); (E.H.); (H.w.B.); (Y.K.L.); (K.H.L.); (Y.C.R.)
| | - Yoon Chan Rah
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Ansan Hospital, Ansan 15355, Republic of Korea; (H.S.Y.); (K.T.H.); (S.H.); (S.P.); (E.H.); (H.w.B.); (Y.K.L.); (K.H.L.); (Y.C.R.)
| | - June Choi
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Ansan Hospital, Ansan 15355, Republic of Korea; (H.S.Y.); (K.T.H.); (S.H.); (S.P.); (E.H.); (H.w.B.); (Y.K.L.); (K.H.L.); (Y.C.R.)
- Zebrafish Translational Medical Research Center, Korea University, Ansan 15355, Republic of Korea
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11
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Liu YC, Xu K. Macrophage-related immune responses in inner ear: a potential therapeutic target for sensorineural hearing loss. Front Neurosci 2024; 17:1339134. [PMID: 38274500 PMCID: PMC10808290 DOI: 10.3389/fnins.2023.1339134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 12/22/2023] [Indexed: 01/27/2024] Open
Abstract
Hearing loss is the most common sensory disorder in human beings. Cochlear sensory cells are the basis of hearing. Cochlear sensory cells suffer from various acute or chronic injuries, such as excessive sound stimulation, ototoxic drugs, and age-related degeneration. In response to these stresses, the cochlea develops an immune response. In recent years, studies have shown that the immune response of the inner ear has been regarded as one of the important pathological mechanisms of inner ear injury. Therapeutic interventions for inflammatory responses can effectively alleviate different types of inner ear injury. As the main immune cells in the inner ear, macrophages are involved in the process of inner ear injury caused by various exogenous factors. However, its specific role in the immune response of the inner ear is still unclear. This review focuses on discusses the dynamic changes of macrophages during different types of inner ear injury, and clarifies the potential role of macrophage-related immune response in inner ear injury.
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Affiliation(s)
- Yu-Chen Liu
- Queen Mary School, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Kai Xu
- Department of Otolaryngology, Head and Neck Surgery, The Second Affiliated Hospital of Nanchang University, Jiangxi Medical College, Nanchang University, Nanchang, China
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12
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Tan F, Li X, Li X, Xu M, Shahzad KA, Hou L. GelMA/PEDOT:PSS Composite Conductive Hydrogel-Based Generation and Protection of Cochlear Hair Cells through Multiple Signaling Pathways. Biomolecules 2024; 14:95. [PMID: 38254695 PMCID: PMC10812993 DOI: 10.3390/biom14010095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 12/18/2023] [Accepted: 01/05/2024] [Indexed: 01/24/2024] Open
Abstract
Recent advances in cochlear implantology are exemplified by novel functional strategies such as bimodal electroacoustic stimulation, in which the patient has intact low-frequency hearing and profound high-frequency hearing pre-operatively. Therefore, the synergistic restoration of dysfunctional cochlear hair cells and the protection of hair cells from ototoxic insults have become a persistent target pursued for this hybrid system. In this study, we developed a composite GelMA/PEDOT:PSS conductive hydrogel that is suitable as a coating for the cochlear implant electrode for the potential local delivery of otoregenerative and otoprotective drugs. Various material characterization methods (e.g., 1H NMR spectroscopy, FT-IR, EIS, and SEM), experimental models (e.g., murine cochlear organoid and aminoglycoside-induced ototoxic HEI-OC1 cellular model), and biological analyses (e.g., confocal laser scanning microscopy, real time qPCR, flow cytometry, and bioinformatic sequencing) were used. The results demonstrated decent material properties of the hydrogel, such as mechanical (e.g., high tensile stress and Young's modulus), electrochemical (e.g., low impedance and high conductivity), biocompatibility (e.g., satisfactory cochlear cell interaction and free of systemic toxicity), and biosafety (e.g., minimal hemolysis and cell death) features. In addition, the CDR medicinal cocktail sustainably released by the hydrogel not only promoted the expansion of the cochlear stem cells but also boosted the trans-differentiation from cochlear supporting cells into hair cells. Furthermore, hydrogel-based drug delivery protected the hair cells from oxidative stress and various forms of programmed cell death (e.g., apoptosis and ferroptosis). Finally, using large-scale sequencing, we enriched a complex network of signaling pathways that are potentially downstream to various metabolic processes and abundant metabolites. In conclusion, we present a conductive hydrogel-based local delivery of bifunctional drug cocktails, thereby serving as a potential solution to intracochlear therapy of bimodal auditory rehabilitation and diseases beyond.
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Affiliation(s)
- Fei Tan
- Department of ORL-HNS, Shanghai Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200070, China; (X.L.); (M.X.); (K.A.S.)
- Plasma Medicine and Surgical Implants Center, School of Medicine, Tongji University, Shanghai 200070, China
- Department of ORL-HNS, The Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland
- Department of ORL-HNS, The Royal College of Surgeons of England, London WC2A 3PE, UK
| | - Xuran Li
- Department of ORL-HNS, Shanghai Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200070, China; (X.L.); (M.X.); (K.A.S.)
- Plasma Medicine and Surgical Implants Center, School of Medicine, Tongji University, Shanghai 200070, China
| | - Xiao Li
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry, Chemical Engineering and Biotechnology & Center for Advanced Low-Dimension Materials, Donghua University, Shanghai 200051, China; (X.L.); (L.H.)
| | - Maoxiang Xu
- Department of ORL-HNS, Shanghai Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200070, China; (X.L.); (M.X.); (K.A.S.)
- Plasma Medicine and Surgical Implants Center, School of Medicine, Tongji University, Shanghai 200070, China
| | - Khawar Ali Shahzad
- Department of ORL-HNS, Shanghai Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200070, China; (X.L.); (M.X.); (K.A.S.)
- Plasma Medicine and Surgical Implants Center, School of Medicine, Tongji University, Shanghai 200070, China
| | - Lei Hou
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry, Chemical Engineering and Biotechnology & Center for Advanced Low-Dimension Materials, Donghua University, Shanghai 200051, China; (X.L.); (L.H.)
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13
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Han L, Wang Z, Wang D, Gao Z, Hu S, Shi D, Shu Y. Mechanisms and otoprotective strategies of programmed cell death on aminoglycoside-induced ototoxicity. Front Cell Dev Biol 2024; 11:1305433. [PMID: 38259515 PMCID: PMC10800616 DOI: 10.3389/fcell.2023.1305433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Accepted: 12/14/2023] [Indexed: 01/24/2024] Open
Abstract
Aminoglycosides are commonly used for the treatment of life-threatening bacterial infections, however, aminoglycosides may cause irreversible hearing loss with a long-term clinical therapy. The mechanism and prevention of the ototoxicity of aminoglycosides are still limited although amounts of studies explored widely. Specifically, advancements in programmed cell death (PCD) provide more new perspectives. This review summarizes the general signal pathways in programmed cell death, including apoptosis, autophagy, and ferroptosis, as well as the mechanisms of aminoglycoside-induced ototoxicity. Additionally, novel interventions, especially gene therapy strategies, are also investigated for the prevention or treatment of aminoglycoside-induced hearing loss with prospective clinical applications.
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Affiliation(s)
- Lei Han
- Department of Otorhinolaryngology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
- ENT Institute and Department of Otorhinolaryngology, Eye and 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
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, China
| | - Zijing Wang
- Department of Otorhinolaryngology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
- ENT Institute and Department of Otorhinolaryngology, Eye and 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
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, China
| | - Daqi Wang
- ENT Institute and Department of Otorhinolaryngology, Eye and 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
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, China
| | - Ziwen Gao
- ENT Institute and Department of Otorhinolaryngology, Eye and 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
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, China
| | - Shaowei Hu
- ENT Institute and Department of Otorhinolaryngology, Eye and 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
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, China
| | - Dazhi Shi
- Department of Otorhinolaryngology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
| | - Yilai Shu
- Department of Otorhinolaryngology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
- ENT Institute and Department of Otorhinolaryngology, Eye and 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
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, China
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14
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Qi J, Tan F, Zhang L, Zhou Y, Zhang Z, Sun Q, Li N, Fang Y, Chen X, Wu Y, Zhong G, Chai R. Critical role of TPRN rings in the stereocilia for hearing. Mol Ther 2024; 32:204-217. [PMID: 37952086 PMCID: PMC10787140 DOI: 10.1016/j.ymthe.2023.11.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 09/29/2023] [Accepted: 11/09/2023] [Indexed: 11/14/2023] Open
Abstract
Inner ear hair cells detect sound vibration through the deflection of mechanosensory stereocilia. Cytoplasmic protein TPRN has been shown to localize at the taper region of the stereocilia, and mutations in TPRN cause hereditary hearing loss through an unknown mechanism. Here, using biochemistry and dual stimulated emission depletion microscopy imaging, we show that the TPRN, together with its binding proteins CLIC5 and PTPRQ, forms concentric rings in the taper region of stereocilia. The disruption of TPRN rings, triggered by the competitive inhibition of the interaction of TPRN and CLIC5 or exogenous TPRN overexpression, leads to stereocilia degeneration and severe hearing loss. Most importantly, restoration of the TPRN rings can rescue the damaged auditory function of Tprn knockout mice by exogenously expressing TPRN at an appropriate level in HCs via promoter recombinant adeno-associated virus (AAV). In summary, our results reveal highly structured TPRN rings near the taper region of stereocilia that are crucial for stereocilia function and hearing. Also, TPRN ring restoration in stereocilia by AAV-Tprn effectively repairs damaged hearing, which lays the foundation for the clinical application of AAV-mediated gene therapy in patients with TPRN mutation.
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Affiliation(s)
- Jieyu Qi
- State Key Laboratory of Digital Medical Engineering, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, School of Medicine, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China; Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, China; School of Life Science, Beijing Institute of Technology, Beijing 100081, China.
| | - Fangzhi Tan
- State Key Laboratory of Digital Medical Engineering, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, School of Medicine, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China.
| | - Liyan Zhang
- State Key Laboratory of Digital Medical Engineering, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, School of Medicine, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China
| | - Yinyi Zhou
- State Key Laboratory of Digital Medical Engineering, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, School of Medicine, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China
| | - Ziyu Zhang
- State Key Laboratory of Digital Medical Engineering, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, School of Medicine, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China
| | - Qiuhan Sun
- State Key Laboratory of Digital Medical Engineering, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, School of Medicine, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China
| | - Nianci Li
- State Key Laboratory of Digital Medical Engineering, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, School of Medicine, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China
| | - Yuan Fang
- State Key Laboratory of Digital Medical Engineering, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, School of Medicine, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China
| | - Xin Chen
- State Key Laboratory of Digital Medical Engineering, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, School of Medicine, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China
| | - Yunhao Wu
- State Key Laboratory of Digital Medical Engineering, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, School of Medicine, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China
| | - Guisheng Zhong
- iHuman Institute, ShanghaiTech University, Shanghai 201210, China; School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.
| | - Renjie Chai
- State Key Laboratory of Digital Medical Engineering, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, School of Medicine, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China; Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, China; School of Life Science, Beijing Institute of Technology, Beijing 100081, China; Department of Otolaryngology Head and Neck Surgery, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu 610072, China; Southeast University Shenzhen Research Institute, Shenzhen 518063, China.
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15
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Lye J, Delaney DS, Leith FK, Sardesai VS, McLenachan S, Chen FK, Atlas MD, Wong EYM. Recent Therapeutic Progress and Future Perspectives for the Treatment of Hearing Loss. Biomedicines 2023; 11:3347. [PMID: 38137568 PMCID: PMC10741758 DOI: 10.3390/biomedicines11123347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 12/06/2023] [Accepted: 12/11/2023] [Indexed: 12/24/2023] Open
Abstract
Up to 1.5 billion people worldwide suffer from various forms of hearing loss, with an additional 1.1 billion people at risk from various insults such as increased consumption of recreational noise-emitting devices and ageing. The most common type of hearing impairment is sensorineural hearing loss caused by the degeneration or malfunction of cochlear hair cells or spiral ganglion nerves in the inner ear. There is currently no cure for hearing loss. However, emerging frontier technologies such as gene, drug or cell-based therapies offer hope for an effective cure. In this review, we discuss the current therapeutic progress for the treatment of hearing loss. We describe and evaluate the major therapeutic approaches being applied to hearing loss and summarize the key trials and studies.
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Affiliation(s)
- Joey Lye
- Hearing Therapeutics, Ear Science Institute Australia, Nedlands, WA 6009, Australia; (J.L.); (D.S.D.); (F.K.L.); (V.S.S.); (M.D.A.)
- Centre for Ear Sciences, Medical School, The University of Western Australia, Nedlands, WA 6009, Australia
| | - Derek S. Delaney
- Hearing Therapeutics, Ear Science Institute Australia, Nedlands, WA 6009, Australia; (J.L.); (D.S.D.); (F.K.L.); (V.S.S.); (M.D.A.)
- Faculty of Health Sciences, Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6102, Australia
| | - Fiona K. Leith
- Hearing Therapeutics, Ear Science Institute Australia, Nedlands, WA 6009, Australia; (J.L.); (D.S.D.); (F.K.L.); (V.S.S.); (M.D.A.)
- Centre for Ear Sciences, Medical School, The University of Western Australia, Nedlands, WA 6009, Australia
| | - Varda S. Sardesai
- Hearing Therapeutics, Ear Science Institute Australia, Nedlands, WA 6009, Australia; (J.L.); (D.S.D.); (F.K.L.); (V.S.S.); (M.D.A.)
| | - Samuel McLenachan
- Ocular Tissue Engineering Laboratory, Lions Eye Institute, Nedlands, WA 6009, Australia; (S.M.); (F.K.C.)
- Centre for Ophthalmology and Visual Sciences, The University of Western Australia, Nedlands, WA 6009, Australia
| | - Fred K. Chen
- Ocular Tissue Engineering Laboratory, Lions Eye Institute, Nedlands, WA 6009, Australia; (S.M.); (F.K.C.)
- Centre for Ophthalmology and Visual Sciences, The University of Western Australia, Nedlands, WA 6009, Australia
- Vitroretinal Surgery, Royal Perth Hospital, Perth, WA 6000, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, East Melbourne, VIC 3002, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, VIC 3002, Australia
| | - Marcus D. Atlas
- Hearing Therapeutics, Ear Science Institute Australia, Nedlands, WA 6009, Australia; (J.L.); (D.S.D.); (F.K.L.); (V.S.S.); (M.D.A.)
- Centre for Ear Sciences, Medical School, The University of Western Australia, Nedlands, WA 6009, Australia
| | - Elaine Y. M. Wong
- Hearing Therapeutics, Ear Science Institute Australia, Nedlands, WA 6009, Australia; (J.L.); (D.S.D.); (F.K.L.); (V.S.S.); (M.D.A.)
- Centre for Ear Sciences, Medical School, The University of Western Australia, Nedlands, WA 6009, Australia
- Curtin Medical School, Faculty of Health Sciences, Curtin University, Bentley, WA 6102, Australia
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16
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Suzuki J, Hemmi T, Maekawa M, Watanabe M, Inada H, Ikushima H, Oishi T, Ikeda R, Honkura Y, Kagawa Y, Kawase T, Mano N, Owada Y, Osumi N, Katori Y. Fatty acid binding protein type 7 deficiency preserves auditory function in noise-exposed mice. Sci Rep 2023; 13:21494. [PMID: 38057582 PMCID: PMC10700610 DOI: 10.1038/s41598-023-48702-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 11/29/2023] [Indexed: 12/08/2023] Open
Abstract
Fatty acid-binding protein 7 (FABP7) is vital for uptake and trafficking of fatty acids in the nervous system. To investigate the involvement of FABP7 in noise-induced hearing loss (NIHL) pathogenesis, we used Fabp7 knockout (KO) mice generated via CRISPR/Cas9 in the C57BL/6 background. Initial auditory brainstem response (ABR) measurements were conducted at 9 weeks, followed by noise exposure at 10 weeks. Subsequent ABRs were performed 24 h later, with final measurements at 12 weeks. Inner ears were harvested 24 h after noise exposure for RNA sequencing and metabolic analyses. We found no significant differences in initial ABR measurements, but Fabp7 KO mice showed significantly lower thresholds in the final ABR measurements. Hair cell survival was also enhanced in Fabp7 KO mice. RNA sequencing revealed that genes associated with the electron transport chain were upregulated or less impaired in Fabp7 KO mice. Metabolomic analysis revealed various alterations, including decreased glutamate and aspartate in Fabp7 KO mice. In conclusion, FABP7 deficiency mitigates cochlear damage following noise exposure. This protective effect was supported by the changes in gene expression of the electron transport chain, and in several metabolites, including excitotoxic neurotransmitters. Our study highlights the potential therapeutic significance of targeting FABP7 in NIHL.
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Affiliation(s)
- Jun Suzuki
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan.
| | - Tomotaka Hemmi
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Masamitsu Maekawa
- Department of Pharmaceutical Sciences, Tohoku University Hospital, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
- Graduate School of Pharmaceutical Sciences, Tohoku University, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Masahiro Watanabe
- Graduate School of Pharmaceutical Sciences, Tohoku University, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Hitoshi Inada
- Department of Developmental Neuroscience, Centers for Neuroscience, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Hiroyuki Ikushima
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Tetsuya Oishi
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Ryoukichi Ikeda
- Department of Otolaryngology, Head and Neck Surgery, Iwate Medical University School of Medicine, 19-1 Odori, Yahaba, Shiwa, 020-8505, Japan
| | - Yohei Honkura
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Yoshiteru Kagawa
- Department of Organ Anatomy, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Tetsuaki Kawase
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Nariyasu Mano
- Department of Pharmaceutical Sciences, Tohoku University Hospital, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
- Graduate School of Pharmaceutical Sciences, Tohoku University, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Yuji Owada
- Department of Organ Anatomy, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Noriko Osumi
- Department of Developmental Neuroscience, Centers for Neuroscience, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Yukio Katori
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
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17
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Saegusa C, Kakegawa W, Miura E, Aimi T, Mogi S, Harada T, Yamashita T, Yuzaki M, Fujioka M. Brain-Specific Angiogenesis Inhibitor 3 Is Expressed in the Cochlea and Is Necessary for Hearing Function in Mice. Int J Mol Sci 2023; 24:17092. [PMID: 38069416 PMCID: PMC10707444 DOI: 10.3390/ijms242317092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 11/27/2023] [Accepted: 11/29/2023] [Indexed: 12/18/2023] Open
Abstract
Mammalian auditory hair cells transduce sound-evoked traveling waves in the cochlea into nerve stimuli, which are essential for hearing function. Pillar cells located between the inner and outer hair cells are involved in the formation of the tunnel of Corti, which incorporates outer-hair-cell-driven fluid oscillation and basilar membrane movement, leading to the fine-tuned frequency-specific perception of sounds by the inner hair cells. However, the detailed molecular mechanism underlying the development and maintenance of pillar cells remains to be elucidated. In this study, we examined the expression and function of brain-specific angiogenesis inhibitor 3 (Bai3), an adhesion G-protein-coupled receptor, in the cochlea. We found that Bai3 was expressed in hair cells in neonatal mice and pillar cells in adult mice, and, interestingly, Bai3 knockout mice revealed the abnormal formation of pillar cells, with the elevation of the hearing threshold in a frequency-dependent manner. Furthermore, old Bai3 knockout mice showed the degeneration of hair cells and spiral ganglion neurons in the basal turn. The results suggest that Bai3 plays a crucial role in the development and/or maintenance of pillar cells, which, in turn, are necessary for normal hearing function. Our results may contribute to understanding the mechanisms of hearing loss in human patients.
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Affiliation(s)
- Chika Saegusa
- Department of Molecular Genetics, Kitasato University School of Medicine, Kanagawa 252-0374, Japan;
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Wataru Kakegawa
- Department of Physiology, Keio University School of Medicine, Tokyo 160-8582, Japan; (W.K.); (E.M.); (T.A.); (M.Y.)
| | - Eriko Miura
- Department of Physiology, Keio University School of Medicine, Tokyo 160-8582, Japan; (W.K.); (E.M.); (T.A.); (M.Y.)
| | - Takahiro Aimi
- Department of Physiology, Keio University School of Medicine, Tokyo 160-8582, Japan; (W.K.); (E.M.); (T.A.); (M.Y.)
| | - Sachiyo Mogi
- Department of Otorhinolaryngology, Head and Neck Surgery, Kitasato University, Kanagawa 252-0374, Japan; (S.M.); (T.Y.)
| | - Tatsuhiko Harada
- Department of Otolaryngology, International University of Health and Welfare, Shizuoka 413-0012, Japan;
| | - Taku Yamashita
- Department of Otorhinolaryngology, Head and Neck Surgery, Kitasato University, Kanagawa 252-0374, Japan; (S.M.); (T.Y.)
| | - Michisuke Yuzaki
- Department of Physiology, Keio University School of Medicine, Tokyo 160-8582, Japan; (W.K.); (E.M.); (T.A.); (M.Y.)
| | - Masato Fujioka
- Department of Molecular Genetics, Kitasato University School of Medicine, Kanagawa 252-0374, Japan;
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo 160-8582, Japan
- Clinical and Translational Research Center, Keio University Hospital, Tokyo 162-8582, Japan
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18
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Moser T, Karagulyan N, Neef J, Jaime Tobón LM. Diversity matters - extending sound intensity coding by inner hair cells via heterogeneous synapses. EMBO J 2023; 42:e114587. [PMID: 37800695 PMCID: PMC10690447 DOI: 10.15252/embj.2023114587] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 06/26/2023] [Accepted: 08/07/2023] [Indexed: 10/07/2023] Open
Abstract
Our sense of hearing enables the processing of stimuli that differ in sound pressure by more than six orders of magnitude. How to process a wide range of stimulus intensities with temporal precision is an enigmatic phenomenon of the auditory system. Downstream of dynamic range compression by active cochlear micromechanics, the inner hair cells (IHCs) cover the full intensity range of sound input. Yet, the firing rate in each of their postsynaptic spiral ganglion neurons (SGNs) encodes only a fraction of it. As a population, spiral ganglion neurons with their respective individual coding fractions cover the entire audible range. How such "dynamic range fractionation" arises is a topic of current research and the focus of this review. Here, we discuss mechanisms for generating the diverse functional properties of SGNs and formulate testable hypotheses. We postulate that an interplay of synaptic heterogeneity, molecularly distinct subtypes of SGNs, and efferent modulation serves the neural decomposition of sound information and thus contributes to a population code for sound intensity.
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Affiliation(s)
- Tobias Moser
- Institute for Auditory Neuroscience and InnerEarLabUniversity Medical Center GöttingenGöttingenGermany
- Auditory Neuroscience and Synaptic Nanophysiology GroupMax Planck Institute for Multidisciplinary SciencesGöttingenGermany
- Cluster of Excellence “Multiscale Bioimaging of Excitable Cells”GöttingenGermany
| | - Nare Karagulyan
- Institute for Auditory Neuroscience and InnerEarLabUniversity Medical Center GöttingenGöttingenGermany
- Auditory Neuroscience and Synaptic Nanophysiology GroupMax Planck Institute for Multidisciplinary SciencesGöttingenGermany
- Hertha Sponer CollegeCluster of Excellence “Multiscale Bioimaging of Excitable Cells” Cluster of ExcellenceGöttingenGermany
| | - Jakob Neef
- Institute for Auditory Neuroscience and InnerEarLabUniversity Medical Center GöttingenGöttingenGermany
- Auditory Neuroscience and Synaptic Nanophysiology GroupMax Planck Institute for Multidisciplinary SciencesGöttingenGermany
| | - Lina María Jaime Tobón
- Institute for Auditory Neuroscience and InnerEarLabUniversity Medical Center GöttingenGöttingenGermany
- Auditory Neuroscience and Synaptic Nanophysiology GroupMax Planck Institute for Multidisciplinary SciencesGöttingenGermany
- Hertha Sponer CollegeCluster of Excellence “Multiscale Bioimaging of Excitable Cells” Cluster of ExcellenceGöttingenGermany
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19
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Zhou LY, Jin CX, Wang WX, Song L, Shin JB, Du TT, Wu H. Differential regulation of hair cell actin cytoskeleton mediated by SRF and MRTFB. eLife 2023; 12:e90155. [PMID: 37982489 PMCID: PMC10703445 DOI: 10.7554/elife.90155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 11/17/2023] [Indexed: 11/21/2023] Open
Abstract
The MRTF-SRF pathway has been extensively studied for its crucial role in driving the expression of a large number of genes involved in actin cytoskeleton of various cell types. However, the specific contribution of MRTF-SRF in hair cells remains unknown. In this study, we showed that hair cell-specific deletion of Srf or Mrtfb, but not Mrtfa, leads to similar defects in the development of stereocilia dimensions and the maintenance of cuticular plate integrity. We used fluorescence-activated cell sorting-based hair cell RNA-Seq analysis to investigate the mechanistic underpinnings of the changes observed in Srf and Mrtfb mutants, respectively. Interestingly, the transcriptome analysis revealed distinct profiles of genes regulated by Srf and Mrtfb, suggesting different transcriptional regulation mechanisms of actin cytoskeleton activities mediated by Srf and Mrtfb. Exogenous delivery of calponin 2 using Adeno-associated virus transduction in Srf mutants partially rescued the impairments of stereocilia dimensions and the F-actin intensity of cuticular plate, suggesting the involvement of Cnn2, as an Srf downstream target, in regulating the hair bundle morphology and cuticular plate actin cytoskeleton organization. Our study uncovers, for the first time, the unexpected differential transcriptional regulation of actin cytoskeleton mediated by Srf and Mrtfb in hair cells, and also demonstrates the critical role of SRF-CNN2 in modulating actin dynamics of the stereocilia and cuticular plate, providing new insights into the molecular mechanism underlying hair cell development and maintenance.
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Affiliation(s)
- Ling-Yun Zhou
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Ear Institute, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghaiChina
| | - Chen-Xi Jin
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Ear Institute, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghaiChina
| | - Wen-Xiao Wang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Ear Institute, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghaiChina
| | - Lei Song
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Ear Institute, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghaiChina
| | - Jung-Bum Shin
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
| | - Ting-Ting Du
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Ear Institute, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghaiChina
| | - Hao Wu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Ear Institute, Shanghai Jiao Tong University School of MedicineShanghaiChina
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghaiChina
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20
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Smith ET, Sun P, Yu SK, Raible DW, Nicolson T. Differential expression of mechanotransduction complex genes in auditory/vestibular hair cells in zebrafish. Front Mol Neurosci 2023; 16:1274822. [PMID: 38035267 PMCID: PMC10682102 DOI: 10.3389/fnmol.2023.1274822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 10/23/2023] [Indexed: 12/02/2023] Open
Abstract
Ciliated sensory cells such as photo- and olfactory receptors employ multiple types of opsins or hundreds of unique olfactory G-protein coupled receptors to respond to various wavelengths of light or odorants. With respect to hearing and balance, the mechanotransduction machinery involves fewer variants; however, emerging evidence suggests that specialization occurs at the molecular level. To address how the mechanotransduction complex varies in the inner ear, we characterized the expression of paralogous genes that encode components required for mechanotransduction in zebrafish hair cells using RNA-FISH and bioinformatic analysis. Our data indicate striking zonal differences in the expression of two components of the mechanotransduction complex which are known to physically interact, the transmembrane channel-like 1 and 2 (tmc1/2) family members and the calcium and integrin binding 2 and 3 (cib2/3) paralogues. tmc1, tmc2b, and cib3 are largely expressed in peripheral or extrastriolar hair cells, whereas tmc2a and cib2 are enriched in central or striolar hair cells. In addition, a gene implicated in deaf-blindness, ush1c, is highly enriched in a subset of extrastriolar hair cells. These results indicate that specific combinations of these components may optimize responses to mechanical stimuli in subtypes of sensory receptors within the inner ear.
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Affiliation(s)
- Eliot T. Smith
- Department of Otolaryngology-HNS, Stanford University, Stanford, CA, United States
| | - Peng Sun
- Department of Otolaryngology-HNS, Stanford University, Stanford, CA, United States
| | - Shengyang Kevin Yu
- Department of Otolaryngology-HNS and Biological Structure, Viginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA, United States
| | - David W. Raible
- Department of Otolaryngology-HNS and Biological Structure, Viginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA, United States
| | - Teresa Nicolson
- Department of Otolaryngology-HNS, Stanford University, Stanford, CA, United States
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21
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Derudas M, O’Reilly M, Kirkwood NK, Kenyon EJ, Grimsey S, Kitcher SR, Workman S, Bull JC, Ward SE, Kros CJ, Richardson GP. Charge and lipophilicity are required for effective block of the hair-cell mechano-electrical transducer channel by FM1-43 and its derivatives. Front Cell Dev Biol 2023; 11:1247324. [PMID: 37900280 PMCID: PMC10601989 DOI: 10.3389/fcell.2023.1247324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 09/19/2023] [Indexed: 10/31/2023] Open
Abstract
The styryl dye FM1-43 is widely used to study endocytosis but behaves as a permeant blocker of the mechano-electrical transducer (MET) channel in sensory hair cells, loading rapidly and specifically into the cytoplasm of hair cells in a MET channel-dependent manner. Patch clamp recordings of mouse outer hair cells (OHCs) were used to determine how a series of structural modifications of FM1-43 affect MET channel block. Fluorescence microscopy was used to assess how the modifications influence hair-cell loading in mouse cochlear cultures and zebrafish neuromasts. Cochlear cultures were also used to evaluate otoprotective potential of the modified FM1-43 derivatives. Structure-activity relationships reveal that the lipophilic tail and the cationic head group of FM1-43 are both required for MET channel block in mouse cochlear OHCs; neither moiety alone is sufficient. The extent of MET channel block is augmented by increasing the lipophilicity/bulkiness of the tail, by reducing the number of positive charges in the head group from two to one, or by increasing the distance between the two charged head groups. Loading assays with zebrafish neuromasts and mouse cochlear cultures are broadly in accordance with these observations but reveal a loss of hair-cell specific labelling with increasing lipophilicity. Although FM1-43 and many of its derivatives are generally cytotoxic when tested on cochlear cultures in the presence of an equimolar concentration of the ototoxic antibiotic gentamicin (5 µM), at a 10-fold lower concentration (0.5 µM), two of the derivatives protect OHCs from cell death caused by 48 h-exposure to 5 µM gentamicin.
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Affiliation(s)
- Marco Derudas
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
- Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Molly O’Reilly
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
- Department of Experimental Cardiology, Academic Medical Center, Amsterdam, Netherlands
| | - Nerissa K. Kirkwood
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
- School of Biosciences, University of Kent, Canterbury, United Kingdom
| | - Emma J. Kenyon
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
- School of Medicine, Institute of Life Sciences, Swansea University, Swansea, United Kingdom
| | - Sybil Grimsey
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Siân R. Kitcher
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
- Section on Neuronal Circuitry, National Institute on Deafness and Other Communication Disorders NIH, Bethesda, MD, United States
| | - Shawna Workman
- Department of Biosciences, College of Science, Swansea University, Swansea, United Kingdom
| | - James C. Bull
- Department of Biosciences, College of Science, Swansea University, Swansea, United Kingdom
| | - Simon E. Ward
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
- Medicines Discovery Institute, Cardiff University, Cardiff, United Kingdom
| | - Corné J. Kros
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Guy P. Richardson
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
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22
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Liao A, Wang C, Wang B, Lin Y, Chuang H, Liu H, Shih C. Combined use of microbubbles of various sizes and single-transducer dual-frequency ultrasound for safe and efficient inner ear drug delivery. Bioeng Transl Med 2023; 8:e10450. [PMID: 37693043 PMCID: PMC10487305 DOI: 10.1002/btm2.10450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 10/29/2022] [Accepted: 11/08/2022] [Indexed: 11/17/2022] Open
Abstract
We have previously applied ultrasound (US) with microbubbles (MBs) to enhance inner ear drug delivery, with most experiments conducted using single-frequency, high-power density US, and multiple treatments. In the present study, the treatment efficacy was enhanced and safety concerns were addressed using a combination of low-power-density, single-transducer, dual-frequency US (I SPTA = 213 mW/cm2) and MBs of different sizes coated with insulin-like growth factor 1 (IGF-1). This study is the first to investigate the drug-coating capacity of human serum albumin (HSA) MBs of different particle sizes and their drug delivery efficiency. The concentration of HSA was adjusted to produce different MB sizes. The drug-coating efficiency was significantly higher for large-sized MBs than for smaller MBs. In vitro Franz diffusion experiments showed that the combination of dual-frequency US and large MB size delivered the most IGF-1 (24.3 ± 0.47 ng/cm2) to the receptor side at the second hour of treatment. In an in vivo guinea pig experiment, the efficiency of IGF-1 delivery into the inner ear was 15.9 times greater in animals treated with the combination of dual-frequency US and large MBs (D-USMB) than in control animals treated with round window soaking (RWS). The IGF-1 delivery efficiency was 10.15 times greater with the combination of single-frequency US and large size MBs (S-USMB) than with RWS. Confocal microscopy of the cochlea showed a stronger distribution of IGF-1 in the basal turn in the D-USMB and S-USMB groups than in the RWS group. In the second and third turns, the D-USMB group showed the greatest IGF-1 distribution. Hearing assessments revealed no significant differences among the D-USMB, S-USMB, and RWS groups. In conclusion, the combination of single-transducer dual-frequency US and suitably sized MBs can significantly reduce US power density while enhancing the delivery of large molecular weight drugs, such as IGF-1, to the inner ear.
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Affiliation(s)
- Ai‐Ho Liao
- Graduate Institute of Biomedical EngineeringNational Taiwan University of Science and TechnologyTaipeiTaiwan
- Department of Biomedical EngineeringNational Defense Medical CenterTaipeiTaiwan
| | - Chih‐Hung Wang
- Department of Otolaryngology‐Head and Neck Surgery, Tri‐Service General HospitalNational Defense Medical CenterTaipeiTaiwan
- Graduate Institute of Medical SciencesNational Defense Medical CenterTaipeiTaiwan
| | - Bo‐Han Wang
- Department of Mechanical EngineeringNational Taipei University of TechnologyTaipeiTaiwan
| | - Yi‐Chun Lin
- Graduate Institute of Medical SciencesNational Defense Medical CenterTaipeiTaiwan
| | - Ho‐Chiao Chuang
- Department of Mechanical EngineeringNational Taipei University of TechnologyTaipeiTaiwan
| | - Hao‐Li Liu
- Department of Electrical EngineeringNational Taiwan UniversityTaipeiTaiwan
| | - Cheng‐Ping Shih
- Department of Otolaryngology‐Head and Neck Surgery, Tri‐Service General HospitalNational Defense Medical CenterTaipeiTaiwan
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23
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Makrogkikas S, Cheng RK, Lu H, Roy S. A conserved function of Pkhd1l1, a mammalian hair cell stereociliary coat protein, in regulating hearing in zebrafish. J Neurogenet 2023; 37:85-92. [PMID: 36960824 DOI: 10.1080/01677063.2023.2187792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 03/02/2023] [Indexed: 03/25/2023]
Abstract
Pkhd1l1 is predicted to encode a very large type-I transmembrane protein, but its function has largely remained obscure. Recently, it was shown that Pkhdl1l1 is a component of the coat that decorates stereocilia of outer hair cells in the mouse ear. Consistent with this localization, conditional deletion of Pkhd1l1 specifically from hair cells, was associated with progressive hearing loss. In the zebrafish, there are two paralogous pkhd1l1 genes - pkhd1l1α and pkhd1l1β. Using CRISPR-Cas9 mediated gene editing, we generated loss-of-function alleles for both and show that the double mutants exhibit nonsense-mediated-decay (NMD) of the RNAs. With behavioural assays, we demonstrate that zebrafish pkhd1l1 genes also regulate hearing; however, in contrast to Pkhd1l1 mutant mice, which develop progressive hearing loss, the double mutant zebrafish exhibited statistically significant hearing loss even from the larval stage. Our data highlight a conserved function of Pkhd1l1 in hearing and based on these findings from animal models, we postulate that PKHD1L1 could be a candidate gene for sensorineural hearing loss (SNHL) in humans.
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Affiliation(s)
- Stylianos Makrogkikas
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Ruey-Kuang Cheng
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Hao Lu
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Sudipto Roy
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
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24
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Vinay, Moore BCJ. Exploiting individual differences to assess the role of place and phase locking cues in auditory frequency discrimination at 2 kHz. Sci Rep 2023; 13:13801. [PMID: 37612303 PMCID: PMC10447419 DOI: 10.1038/s41598-023-40571-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 08/13/2023] [Indexed: 08/25/2023] Open
Abstract
The relative role of place and temporal mechanisms in auditory frequency discrimination was assessed for a centre frequency of 2 kHz. Four measures of frequency discrimination were obtained for 63 normal-hearing participants: detection of frequency modulation using modulation rates of 2 Hz (FM2) and 20 Hz (FM20); detection of a change in frequency across successive pure tones (difference limen for frequency, DLF); and detection of changes in the temporal fine structure of bandpass filtered complex tones centred at 2 kHz (TFS). Previous work has suggested that: FM2 depends on the use of both temporal and place cues; FM20 depends primarily on the use of place cues because the temporal mechanism cannot track rapid changes in frequency; DLF depends primarily on temporal cues; TFS depends exclusively on temporal cues. This led to the following predicted patterns of the correlations of scores across participants: DLF and TFS should be highly correlated; FM2 should be correlated with DLF and TFS; FM20 should not be correlated with DLF or TFS. The results were broadly consistent with these predictions and with the idea that frequency discrimination at 2 kHz depends partly or primarily on temporal cues except for frequency modulation detection at a high rate.
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Affiliation(s)
- Vinay
- Audiology Group, Department of Neuromedicine and Movement Science, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Tungasletta 2, 7491, Trondheim, Norway.
| | - Brian C J Moore
- Cambridge Hearing Group, Department of Psychology, University of Cambridge, Cambridge, UK
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25
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Wang X, Llamas J, Trecek T, Shi T, Tao L, Makmura W, Crump JG, Segil N, Gnedeva K. SoxC transcription factors shape the epigenetic landscape to establish competence for sensory differentiation in the mammalian organ of Corti. Proc Natl Acad Sci U S A 2023; 120:e2301301120. [PMID: 37585469 PMCID: PMC10450657 DOI: 10.1073/pnas.2301301120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 06/28/2023] [Indexed: 08/18/2023] Open
Abstract
The auditory organ of Corti is comprised of only two major cell types-the mechanosensory hair cells and their associated supporting cells-both specified from a single pool of prosensory progenitors in the cochlear duct. Here, we show that competence to respond to Atoh1, a transcriptional master regulator necessary and sufficient for induction of mechanosensory hair cells, is established in the prosensory progenitors between E12.0 and 13.5. The transition to the competent state is rapid and is associated with extensive remodeling of the epigenetic landscape controlled by the SoxC group of transcription factors. Conditional loss of Sox4 and Sox11-the two homologous family members transiently expressed in the inner ear at the time of competence establishment-blocks the ability of prosensory progenitors to differentiate as hair cells. Mechanistically, we show that Sox4 binds to and establishes accessibility of early sensory lineage-specific regulatory elements, including ones associated with Atoh1 and its direct downstream targets. Consistent with these observations, overexpression of Sox4 or Sox11 prior to developmental establishment of competence precociously induces hair cell differentiation in the cochlear progenitors. Further, reintroducing Sox4 or Sox11 expression restores the ability of postnatal supporting cells to differentiate as hair cells in vitro and in vivo. Our findings demonstrate the pivotal role of SoxC family members as agents of epigenetic and transcriptional changes necessary for establishing competence for sensory receptor differentiation in the inner ear.
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Affiliation(s)
- Xizi Wang
- Caruso Department of Otolaryngology–Head and Neck Surgery, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
| | - Juan Llamas
- Caruso Department of Otolaryngology–Head and Neck Surgery, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
| | - Talon Trecek
- Caruso Department of Otolaryngology–Head and Neck Surgery, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
| | - Tuo Shi
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
| | - Litao Tao
- Caruso Department of Otolaryngology–Head and Neck Surgery, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
| | - Welly Makmura
- Caruso Department of Otolaryngology–Head and Neck Surgery, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
| | - J. Gage Crump
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
| | - Neil Segil
- Caruso Department of Otolaryngology–Head and Neck Surgery, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
| | - Ksenia Gnedeva
- Caruso Department of Otolaryngology–Head and Neck Surgery, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA90033
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26
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Peters CW, Hanlon KS, Ivanchenko MV, Zinn E, Linarte EF, Li Y, Levy JM, Liu DR, Kleinstiver BP, Indzhykulian AA, Corey DP. Rescue of hearing by adenine base editing in a humanized mouse model of Usher syndrome type 1F. Mol Ther 2023; 31:2439-2453. [PMID: 37312453 PMCID: PMC10421997 DOI: 10.1016/j.ymthe.2023.06.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 04/03/2023] [Accepted: 06/08/2023] [Indexed: 06/15/2023] Open
Abstract
Usher syndrome type 1F (USH1F), characterized by congenital lack of hearing and balance and progressive loss of vision, is caused by mutations in the PCDH15 gene. In the Ashkenazi population, a recessive truncation mutation accounts for a large proportion of USH1F cases. The truncation is caused by a single C→T mutation, which converts an arginine codon to a stop (R245X). To test the potential for base editors to revert this mutation, we developed a humanized Pcdh15R245X mouse model for USH1F. Mice homozygous for the R245X mutation were deaf and exhibited profound balance deficits, while heterozygous mice were unaffected. Here we show that an adenine base editor (ABE) is capable of reversing the R245X mutation to restore the PCDH15 sequence and function. We packaged a split-intein ABE into dual adeno-associated virus (AAV) vectors and delivered them into cochleas of neonatal USH1F mice. Hearing was not restored in a Pcdh15 constitutive null mouse despite base editing, perhaps because of early disorganization of cochlear hair cells. However, injection of vectors encoding the split ABE into a late-deletion conditional Pcdh15 knockout rescued hearing. This study demonstrates the ability of an ABE to correct the PCDH15 R245X mutation in the cochlea and restore hearing.
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Affiliation(s)
- Cole W Peters
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Killian S Hanlon
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School and Massachusetts General Hospital, Boston, MA 02114, USA
| | | | - Eric Zinn
- Grousbeck Gene Therapy Center, Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, MA 02114, USA
| | | | - Yaqiao Li
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Jonathan M Levy
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA; Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - David R Liu
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA; Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - Benjamin P Kleinstiver
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Pathology, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Pathology, Harvard Medical School, Boston, MA 02115, USA
| | - Artur A Indzhykulian
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA; Department of Otolaryngology - Head and Neck Surgery, Harvard Medical School and Massachusetts Eye and Ear, Boston, MA 02114, USA
| | - David P Corey
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
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Siebald C, Vincent PFY, Bottom RT, Sun S, Reijntjes DOJ, Manca M, Glowatzki E, Müller U. Molecular signatures define subtypes of auditory afferents with distinct peripheral projection patterns and physiological properties. Proc Natl Acad Sci U S A 2023; 120:e2217033120. [PMID: 37487063 PMCID: PMC10400978 DOI: 10.1073/pnas.2217033120] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 06/06/2023] [Indexed: 07/26/2023] Open
Abstract
Type I spiral ganglion neurons (SGNs) are the auditory afferents that transmit sound information from cochlear inner hair cells (IHCs) to the brainstem. These afferents consist of physiological subtypes that differ in their spontaneous firing rate (SR), activation threshold, and dynamic range and have been described as low, medium, and high SR fibers. Lately, single-cell RNA sequencing experiments have revealed three molecularly defined type I SGN subtypes. The extent to which physiological type I SGN subtypes correspond to molecularly defined subtypes is unclear. To address this question, we have generated mouse lines expressing CreERT2 in SGN subtypes that allow for a physiological assessment of molecular subtypes. We show that Lypd1-CreERT2 expressing SGNs represent a well-defined group of neurons that preferentially innervate the IHC modiolar side and exhibit a narrow range of low SRs. In contrast, Calb2-CreERT2 expressing SGNs preferentially innervate the IHC pillar side and exhibit a wider range of SRs, thus suggesting that a strict stratification of all SGNs into three molecular subclasses is not obvious, at least not with the CreERT2 tools used here. Genetically marked neuronal subtypes refine their innervation specificity onto IHCs postnatally during the time when activity is required to refine their molecular phenotype. Type I SGNs thus consist of genetically defined subtypes with distinct physiological properties and innervation patterns. The molecular subtype-specific lines characterized here will provide important tools for investigating the role of the physiologically distinct type I SGNs in encoding sound signals.
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Affiliation(s)
- Caroline Siebald
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD21205
| | - Philippe F. Y. Vincent
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD21205
| | - Riley T. Bottom
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD21205
| | - Shuohao Sun
- National Institute of Biological Science, Beijing102206, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing100084, China
| | - Daniel O. J. Reijntjes
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD21205
| | - Marco Manca
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD21205
| | - Elisabeth Glowatzki
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD21205
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD21205
| | - Ulrich Müller
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD21205
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28
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Vartanian V, Krey JF, Chatterjee P, Curtis A, Six M, Rice SPM, Jones SM, Sampath H, Allen CN, Ryals RC, Lloyd RS, Barr‐Gillespie PG. Spontaneous allelic variant in deafness-blindness gene Ush1g resulting in an expanded phenotype. Genes Brain Behav 2023; 22:e12849. [PMID: 37328946 PMCID: PMC10393423 DOI: 10.1111/gbb.12849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/05/2023] [Accepted: 05/07/2023] [Indexed: 06/18/2023]
Abstract
Relationships between novel phenotypic behaviors and specific genetic alterations are often discovered using target-specific, directed mutagenesis or phenotypic selection following chemical mutagenesis. An alternative approach is to exploit deficiencies in DNA repair pathways that maintain genetic integrity in response to spontaneously induced damage. Mice deficient in the DNA glycosylase NEIL1 show elevated spontaneous mutations, which arise from translesion DNA synthesis past oxidatively induced base damage. Several litters of Neil1 knockout mice included animals that were distinguished by their backwards-walking behavior in open-field environments, while maintaining frantic forward movements in their home cage environment. Other phenotypic manifestations included swim test failures, head tilting and circling. Mapping of the mutation that conferred these behaviors showed the introduction of a stop codon at amino acid 4 of the Ush1g gene. Ush1gbw/bw null mice displayed auditory and vestibular defects that are commonly seen with mutations affecting inner-ear hair-cell function, including a complete lack of auditory brainstem responses and vestibular-evoked potentials. As in other Usher syndrome type I mutant mouse lines, hair cell phenotypes included disorganized and split hair bundles, as well as altered distribution of proteins for stereocilia that localize to the tips of row 1 or row 2. Disruption to the bundle and kinocilium displacement suggested that USH1G is essential for forming the hair cell's kinocilial links. Consistent with other Usher type 1 models, Ush1gbw/bw mice had no substantial retinal degeneration compared with Ush1gbw /+ controls. In contrast to previously described Ush1g alleles, this new allele provides the first knockout model for this gene.
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Affiliation(s)
- Vladimir Vartanian
- Oregon Institute of Occupational Health SciencesOregon Health & Science UniversityPortlandOregonUSA
| | - Jocelyn F. Krey
- Oregon Hearing Research Center and Vollum InstituteOregon Health & Science UniversityPortlandOregonUSA
| | - Paroma Chatterjee
- Oregon Hearing Research Center and Vollum InstituteOregon Health & Science UniversityPortlandOregonUSA
| | - Allison Curtis
- Department of Ophthalmology, Casey Eye InstituteOregon Health & Science UniversityPortlandOregonUSA
| | - Makayla Six
- Department of Ophthalmology, Casey Eye InstituteOregon Health & Science UniversityPortlandOregonUSA
| | - Sean P. M. Rice
- Oregon Institute of Occupational Health Sciences and School of Public HealthOregon Health & Science University‐Portland State UniversityPortlandOregonUSA
| | - Sherri M. Jones
- Department of Special Education and Communication DisordersUniversity of Nebraska‐LincolnLincolnNebraskaUSA
| | - Harini Sampath
- Department of Nutritional Sciences and New Jersey Institute for Food, Nutrition, and HealthRutgers UniversityNew BrunswickNew JerseyUSA
| | - Charles N. Allen
- Oregon Institute of Occupational Health Sciences and Department of Behavioral NeuroscienceOregon Health & Science UniversityPortlandOregonUSA
| | - Renee C. Ryals
- Department of Ophthalmology, Casey Eye InstituteOregon Health & Science UniversityPortlandOregonUSA
| | - R. Stephen Lloyd
- Oregon Institute of Occupational Health SciencesOregon Health & Science UniversityPortlandOregonUSA
- Department of Molecular and Medical GeneticsOregon Health & Science UniversityPortlandOregonUSA
| | - Peter G. Barr‐Gillespie
- Oregon Hearing Research Center and Vollum InstituteOregon Health & Science UniversityPortlandOregonUSA
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29
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Zou S, Liu W, Sun Y, Zheng Q, He Z. Editorial: Gene therapy for hearing loss: from mechanism to clinic. Front Neurosci 2023; 17:1235627. [PMID: 37502684 PMCID: PMC10369341 DOI: 10.3389/fnins.2023.1235627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 07/03/2023] [Indexed: 07/29/2023] Open
Affiliation(s)
- Shengyu Zou
- Department of Otorhinolaryngology-Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Wenwen Liu
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, China
| | - Yu Sun
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qingyin Zheng
- Department of Otolaryngology-Head & Neck Surgery, Case Western Reserve University, Cleveland, OH, United States
| | - Zuhong He
- Department of Otorhinolaryngology-Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China
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30
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Moore ST, Nakamura T, Nie J, Solivais AJ, Aristizábal-Ramírez I, Ueda Y, Manikandan M, Reddy VS, Romano DR, Hoffman JR, Perrin BJ, Nelson RF, Frolenkov GI, Chuva de Sousa Lopes SM, Hashino E. Generating high-fidelity cochlear organoids from human pluripotent stem cells. Cell Stem Cell 2023; 30:950-961.e7. [PMID: 37419105 PMCID: PMC10695300 DOI: 10.1016/j.stem.2023.06.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 05/15/2023] [Accepted: 06/14/2023] [Indexed: 07/09/2023]
Abstract
Mechanosensitive hair cells in the cochlea are responsible for hearing but are vulnerable to damage by genetic mutations and environmental insults. The paucity of human cochlear tissues makes it difficult to study cochlear hair cells. Organoids offer a compelling platform to study scarce tissues in vitro; however, derivation of cochlear cell types has proven non-trivial. Here, using 3D cultures of human pluripotent stem cells, we sought to replicate key differentiation cues of cochlear specification. We found that timed modulations of Sonic Hedgehog and WNT signaling promote ventral gene expression in otic progenitors. Ventralized otic progenitors subsequently give rise to elaborately patterned epithelia containing hair cells with morphology, marker expression, and functional properties consistent with both outer and inner hair cells in the cochlea. These results suggest that early morphogenic cues are sufficient to drive cochlear induction and establish an unprecedented system to model the human auditory organ.
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Affiliation(s)
- Stephen T Moore
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Takashi Nakamura
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Otolaryngology-Head & Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Jing Nie
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Alexander J Solivais
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | | | - Yoshitomo Ueda
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Mayakannan Manikandan
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - V Shweta Reddy
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Daniel R Romano
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - John R Hoffman
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Benjamin J Perrin
- Department of Biology, Purdue School of Science, Indianapolis, IN 46202, USA
| | - Rick F Nelson
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | | | | | - Eri Hashino
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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31
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Fettiplace R. Cochlear tonotopy from proteins to perception. Bioessays 2023:e2300058. [PMID: 37329318 DOI: 10.1002/bies.202300058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 06/01/2023] [Indexed: 06/19/2023]
Abstract
A ubiquitous feature of the auditory organ in amniotes is the longitudinal mapping of neuronal characteristic frequencies (CFs), which increase exponentially with distance along the organ. The exponential tonotopic map reflects variation in hair cell properties according to cochlear location and is thought to stem from concentration gradients in diffusible morphogenic proteins during embryonic development. While in all amniotes the spatial gradient is initiated by sonic hedgehog (SHH), released from the notochord and floorplate, subsequent molecular pathways are not fully understood. In chickens, BMP7 is one such morphogen, secreted from the distal end of the cochlea. In mammals, the developmental mechanism differs from birds and may depend on cochlear location. A consequence of exponential maps is that each octave occupies an equal distance on the cochlea, a spacing preserved in the tonotopic maps in higher auditory brain regions. This may facilitate frequency analysis and recognition of acoustic sequences.
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Affiliation(s)
- Robert Fettiplace
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
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32
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Wang C, Wang X, Zheng H, Yao J, Xiang Y, Liu D. The ndrg2 Gene Regulates Hair Cell Morphogenesis and Auditory Function during Zebrafish Development. Int J Mol Sci 2023; 24:10002. [PMID: 37373150 PMCID: PMC10297845 DOI: 10.3390/ijms241210002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 05/30/2023] [Accepted: 06/05/2023] [Indexed: 06/29/2023] Open
Abstract
Damages of sensory hair cells (HCs) are mainly responsible for sensorineural hearing loss, however, its pathological mechanism is not yet fully understood due to the fact that many potential deafness genes remain unidentified. N-myc downstream-regulated gene 2 (ndrg2) is commonly regarded as a tumor suppressor and a cell stress-responsive gene extensively involved in cell proliferation, differentiation, apoptosis and invasion, while its roles in zebrafish HC morphogenesis and hearing remains unclear. Results of this study suggested that ndrg2 was highly expressed in the HCs of the otic vesicle and neuromasts via in situ hybridization and single-cell RNA sequencing. Ndrg2 loss-of-function larvae showed decreased crista HCs, shortened cilia, and reduced neuromasts and functional HCs, which could be rescued by the microinjection of ndrg2 mRNA. Moreover, ndrg2 deficiency induced attenuated startle response behaviors to sound vibration stimuli. Mechanistically, there were no detectable HC apoptosis and supporting cell changes in the ndrg2 mutants, and HCs were capable of recovering by blocking the Notch signaling pathway, suggesting that ndrg2 was implicated in HC differentiation mediated by Notch. Overall, our study demonstrates that ndrg2 plays crucial roles in HC development and auditory sensory function utilizing the zebrafish model, which provides new insights into the identification of potential deafness genes and regulation mechanism of HC development.
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Affiliation(s)
- Cheng Wang
- Nantong Laboratory of Development and Diseases, School of Life Sciences, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, China; (C.W.); (J.Y.); (Y.X.)
| | - Xin Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Nantong University, Nantong 226001, China;
| | - Hao Zheng
- School of Medicine, Nantong University, Nantong 226001, China;
| | - Jia Yao
- Nantong Laboratory of Development and Diseases, School of Life Sciences, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, China; (C.W.); (J.Y.); (Y.X.)
| | - Yuqing Xiang
- Nantong Laboratory of Development and Diseases, School of Life Sciences, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, China; (C.W.); (J.Y.); (Y.X.)
| | - Dong Liu
- Nantong Laboratory of Development and Diseases, School of Life Sciences, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, China; (C.W.); (J.Y.); (Y.X.)
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Nantong University, Nantong 226001, China;
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33
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Amariutei AE, Jeng JY, Safieddine S, Marcotti W. Recent advances and future challenges in gene therapy for hearing loss. R Soc Open Sci 2023; 10:230644. [PMID: 37325593 PMCID: PMC10265000 DOI: 10.1098/rsos.230644] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 05/19/2023] [Indexed: 06/17/2023]
Abstract
Hearing loss is the most common sensory deficit experienced by humans and represents one of the largest chronic health conditions worldwide. It is expected that around 10% of the world's population will be affected by disabling hearing impairment by 2050. Hereditary hearing loss accounts for most of the known forms of congenital deafness, and over 25% of adult-onset or progressive hearing loss. Despite the identification of well over 130 genes associated with deafness, there is currently no curative treatment for inherited deafness. Recently, several pre-clinical studies in mice that exhibit key features of human deafness have shown promising hearing recovery through gene therapy involving the replacement of the defective gene with a functional one. Although the potential application of this therapeutic approach to humans is closer than ever, substantial further challenges need to be overcome, including testing the safety and longevity of the treatment, identifying critical therapeutic time windows and improving the efficiency of the treatment. Herein, we provide an overview of the recent advances in gene therapy and highlight the current hurdles that the scientific community need to overcome to ensure a safe and secure implementation of this therapeutic approach in clinical trials.
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Affiliation(s)
- Ana E. Amariutei
- School of Biomedical Science, University of Sheffield, Sheffield S10 2TN, UK
| | - Jing-Yi Jeng
- School of Biomedical Science, University of Sheffield, Sheffield S10 2TN, UK
| | - Saaid Safieddine
- Institut Pasteur, Université Paris Cité, Inserm, Institut de l'Audition, F-75012 Paris, France
| | - Walter Marcotti
- School of Biomedical Science, University of Sheffield, Sheffield S10 2TN, UK
- Neuroscience Institute, University of Sheffield, Sheffield S10 2TN, UK
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34
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Jia S, Ratzan EM, Goodrich EJ, Abrar R, Heiland L, Tarchini B, Deans MR. The dark kinase STK32A regulates hair cell planar polarity opposite of EMX2 in the developing mouse inner ear. eLife 2023; 12:e84910. [PMID: 37144879 PMCID: PMC10202454 DOI: 10.7554/elife.84910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 05/03/2023] [Indexed: 05/06/2023] Open
Abstract
The vestibular maculae of the inner ear contain sensory receptor hair cells that detect linear acceleration and contribute to equilibrioception to coordinate posture and ambulatory movements. These hair cells are divided between two groups, separated by a line of polarity reversal (LPR), with oppositely oriented planar-polarized stereociliary bundles that detect motion in opposite directions. The transcription factor EMX2 is known to establish this planar polarized organization in mouse by regulating the distribution of the transmembrane receptor GPR156 at hair cell boundaries in one group of cells. However, the genes regulated by EMX2 in this context were previously not known. Using mouse as a model, we have identified the serine threonine kinase STK32A as a downstream effector negatively regulated by EMX2. Stk32a is expressed in hair cells on one side of the LPR in a pattern complementary to Emx2 expression in hair cells on the opposite side. Stk32a is necessary to align the intrinsic polarity of the bundle with the core planar cell polarity (PCP) proteins in EMX2-negative regions, and is sufficient to reorient bundles when ectopically expressed in neighboring EMX2-positive regions. We demonstrate that STK32A reinforces LPR formation by regulating the apical localization of GPR156. These observations support a model in which bundle orientation is determined through separate mechanisms in hair cells on opposite sides of the maculae, with EMX2-mediated repression of Stk32a determining the final position of the LPR.
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Affiliation(s)
- Shihai Jia
- Department of Neurobiology, Spencer Fox Eccles School of Medicine at the University of UtahSalt Lake CityUnited States
| | - Evan M Ratzan
- Interdepartmental Program in Neuroscience, Spencer Fox Eccles School of Medicine at the University of UtahSalt Lake CityUnited States
- Departments of Otolaryngology and Neurology, Boston Children’s Hospital and Harvard Medical SchoolBostonUnited States
| | - Ellison J Goodrich
- Department of Neurobiology, Spencer Fox Eccles School of Medicine at the University of UtahSalt Lake CityUnited States
| | - Raisa Abrar
- Department of Neurobiology, Spencer Fox Eccles School of Medicine at the University of UtahSalt Lake CityUnited States
| | - Luke Heiland
- Department of Otolaryngology, Spencer Fox Eccles School of Medicine at the University of UtahSalt Lake CityUnited States
| | - Basile Tarchini
- The Jackson LaboratoryBar HarborUnited States
- Tufts University School of MedicineBostonUnited States
| | - Michael R Deans
- Department of Neurobiology, Spencer Fox Eccles School of Medicine at the University of UtahSalt Lake CityUnited States
- Department of Otolaryngology, Spencer Fox Eccles School of Medicine at the University of UtahSalt Lake CityUnited States
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35
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Li J, Liu C, Müller U, Zhao B. Autophagy proteins are essential for aminoglycoside-induced hearing loss. Autophagy 2023; 19:1599-1600. [PMID: 36184596 PMCID: PMC10240987 DOI: 10.1080/15548627.2022.2127525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 09/19/2022] [Accepted: 09/19/2022] [Indexed: 11/02/2022] Open
Abstract
Aminoglycosides (AGs) are widely used to treat severe infections. However, systemically administered AGs preferentially kill cochlear hair cells, resulting in irreversible hearing loss. Recently, we found that AGs bind to RIPOR2 and trigger its rapid translocation in cochlear hair cells. Reducing RIPOR2 expression entirely prevents AG-induced hair cell death and subsequent hearing loss in mice. Next using yeast two-hybrid screening, we found that RIPOR2 interacts with GABARAP, a key macroautophagy/autophagy pathway protein. Following AG treatment, RIPOR2 colocalizes with GABARAP and regulates the activation of autophagy. Remarkably, reducing the expression of GABARAP, or another key autophagy protein MAP1LC3B/LC3B, entirely prevents AG-induced hair cell death and subsequent hearing loss in mice. Furthermore, we found that AGs activate the autophagy pathway specific to mitochondria. Reducing the expression of PINK1 or PRKN/parkin, two key mitophagy proteins, protects hair cells against AG toxicity. Thus, our findings demonstrated that RIPOR2-mediated autophagic dysfunction is essential for AG-induced hearing loss and provided potential therapeutic strategies for preventing AG toxicity.
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Affiliation(s)
- Jinan Li
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Chang Liu
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Ulrich Müller
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Bo Zhao
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
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36
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Mathur PD, Zou J, Neiswanger G, Zhu D, Wang Y, Almishaal AA, Vashist D, Hammond HK, Park AH, Yang J. Adenylyl cyclase 6 plays a minor role in the mouse inner ear and retina. Sci Rep 2023; 13:7075. [PMID: 37127773 PMCID: PMC10151359 DOI: 10.1038/s41598-023-34361-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Accepted: 04/28/2023] [Indexed: 05/03/2023] Open
Abstract
Adenylyl cyclase 6 (AC6) synthesizes second messenger cAMP in G protein-coupled receptor (GPCR) signaling. In cochlear hair cells, AC6 distribution relies on an adhesion GPCR, ADGRV1, which is associated with Usher syndrome (USH), a condition of combined hearing and vision loss. ADGRV1 is a component of the USH type 2 (USH2) protein complex in hair cells and photoreceptors. However, the role of AC6 in the inner ear and retina has not been explored. Here, we found that AC6 distribution in hair cells depends on the USH2 protein complex integrity. Several known AC6 regulators and effectors, which were previously reported to participate in ADGRV1 signaling in vitro, are localized to the stereociliary compartments that overlap with AC6 distribution in hair cells. In young AC6 knockout (Adcy6-/-) mice, the activity of cAMP-dependent protein kinase, but not Akt kinase, is altered in cochleas, while both kinases are normal in vestibular organs. Adult Adcy6-/- mice however exhibit normal hearing function. AC6 is expressed in mouse retinas but rarely in photoreceptors. Adcy6-/- mice have slightly enhanced photopic but normal scotopic vision. Therefore, AC6 may participate in the ADGRV1 signaling in hair cells but AC6 is not essential for cochlear and retinal development and maintenance.
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Affiliation(s)
- Pranav Dinesh Mathur
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah, Salt Lake City, UT, 84132, USA
- Department of Neurobiology, University of Utah, Salt Lake City, UT, 84132, USA
- Vecprobio Inc., San Diego, CA, 92126, USA
| | - Junhuang Zou
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah, Salt Lake City, UT, 84132, USA
| | - Grace Neiswanger
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah, Salt Lake City, UT, 84132, USA
| | - Daniel Zhu
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah, Salt Lake City, UT, 84132, USA
| | - Yong Wang
- Division of Otolaryngology, Department of Surgery, University of Utah, Salt Lake City, UT, 84132, USA
| | - Ali A Almishaal
- Department of Communication Sciences and Disorders, University of Utah, Salt Lake City, UT, 84112, USA
- Department of Speech-Language Pathology and Audiology, College of Applied Medical Sciences, University of Hail, Hail, 81451, Saudi Arabia
| | - Deepti Vashist
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah, Salt Lake City, UT, 84132, USA
| | - H Kirk Hammond
- Division of Cardiovascular Medicine, Department of Medicine, University of California, San Diego, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Albert H Park
- Division of Otolaryngology, Department of Surgery, University of Utah, Salt Lake City, UT, 84132, USA
| | - Jun Yang
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah, Salt Lake City, UT, 84132, USA.
- Department of Neurobiology, University of Utah, Salt Lake City, UT, 84132, USA.
- Division of Otolaryngology, Department of Surgery, University of Utah, Salt Lake City, UT, 84132, USA.
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Gao Y, Khan YA, Mo W, White KI, Perkins M, Pfuetzner RA, Trapani JG, Brunger AT, Nicolson T. Sensory deficit screen identifies nsf mutation that differentially affects SNARE recycling and quality control. Cell Rep 2023; 42:112345. [PMID: 37027300 PMCID: PMC10524599 DOI: 10.1016/j.celrep.2023.112345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 02/24/2023] [Accepted: 03/21/2023] [Indexed: 04/08/2023] Open
Abstract
The AAA+ NSF complex is responsible for SNARE complex disassembly both before and after membrane fusion. Loss of NSF function results in pronounced developmental and degenerative defects. In a genetic screen for sensory deficits in zebrafish, we identified a mutation in nsf, I209N, that impairs hearing and balance in a dosage-dependent manner without accompanying defects in motility, myelination, and innervation. In vitro experiments demonstrate that while the I209N NSF protein recognizes SNARE complexes, the effects on disassembly are dependent upon the type of SNARE complex and I209N concentration. Higher levels of I209N protein produce a modest decrease in binary (syntaxin-SNAP-25) SNARE complex disassembly and residual ternary (syntaxin-1A-SNAP-25-synaptobrevin-2) disassembly, whereas at lower concentrations binary disassembly activity is strongly reduced and ternary disassembly activity is absent. Our study suggests that the differential effect on disassembly of SNARE complexes leads to selective effects on NSF-mediated membrane trafficking and auditory/vestibular function.
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Affiliation(s)
- Yan Gao
- Department of Otolaryngology, Head and Neck Surgery, Stanford Medical School, 300 Pasteur Drive, Stanford, CA 94303, USA
| | - Yousuf A Khan
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Center for Biomedical Informatics Research, Stanford University, Stanford, CA, USA
| | - Weike Mo
- Graduate Program Biomedical Sciences, Oregon Hearing Research Center and Vollum Institute, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - K Ian White
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Matthew Perkins
- Department of Biology and Neuroscience Program, Amherst College, Amherst, MA 01002, USA
| | - Richard A Pfuetzner
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Josef G Trapani
- Department of Biology and Neuroscience Program, Amherst College, Amherst, MA 01002, USA
| | - Axel T Brunger
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Teresa Nicolson
- Department of Otolaryngology, Head and Neck Surgery, Stanford Medical School, 300 Pasteur Drive, Stanford, CA 94303, USA.
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Zine A, Fritzsch B. Early Steps towards Hearing: Placodes and Sensory Development. Int J Mol Sci 2023; 24:6994. [PMID: 37108158 PMCID: PMC10139157 DOI: 10.3390/ijms24086994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/03/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
Sensorineural hearing loss is the most prevalent sensory deficit in humans. Most cases of hearing loss are due to the degeneration of key structures of the sensory pathway in the cochlea, such as the sensory hair cells, the primary auditory neurons, and their synaptic connection to the hair cells. Different cell-based strategies to replace damaged inner ear neurosensory tissue aiming at the restoration of regeneration or functional recovery are currently the subject of intensive research. Most of these cell-based treatment approaches require experimental in vitro models that rely on a fine understanding of the earliest morphogenetic steps that underlie the in vivo development of the inner ear since its initial induction from a common otic-epibranchial territory. This knowledge will be applied to various proposed experimental cell replacement strategies to either address the feasibility or identify novel therapeutic options for sensorineural hearing loss. In this review, we describe how ear and epibranchial placode development can be recapitulated by focusing on the cellular transformations that occur as the inner ear is converted from a thickening of the surface ectoderm next to the hindbrain known as the otic placode to an otocyst embedded in the head mesenchyme. Finally, we will highlight otic and epibranchial placode development and morphogenetic events towards progenitors of the inner ear and their neurosensory cell derivatives.
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Affiliation(s)
- Azel Zine
- LBN, Laboratory of Bioengineering and Nanoscience, University of Montpellier, 34193 Montpellier, France
| | - Bernd Fritzsch
- Department of Biology, CLAS, University of Iowa, Iowa City, IA 52242, USA
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Abstract
Hair cells of the mammalian cochlea are specialized mechanosensory cells that convert mechanical stimuli into electrical signals to initiate the neuronal responses that lead to the perception of sound. The mechanoelectrical transduction (MET) machinery of cochlear hair cells is a multimeric protein complex that consists of the pore forming subunits of the MET channel and several essential accessory subunits that are crucial to regulate channel function and render the channel mechanically sensitive. Mutations have been discovered in the genes that encode all known components of the MET machinery. These mutations cause hearing loss with or without vestibular dysfunction. Some mutations also affect other tissues such as the retina. In this brief review, we will summarize gene mutations that affect the MET machinery of hair cells and how the study of the affected genes has illuminated our understanding of the physiological role of the encoded proteins.
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Affiliation(s)
- Jinsei Jung
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Otorhinolaryngology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Ulrich Müller
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Scharr AL, Ó Maoiléidigh D, Ricci AJ. Coupling between the Stereocilia of Rat Sensory Inner-Hair-Cell Hair Bundles Is Weak, Shaping Their Sensitivity to Stimulation. J Neurosci 2023; 43:2053-2074. [PMID: 36746628 PMCID: PMC10039747 DOI: 10.1523/jneurosci.1588-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 01/16/2023] [Accepted: 01/31/2023] [Indexed: 02/08/2023] Open
Abstract
The hair bundle is the universal mechanosensory organelle of auditory, vestibular, and lateral-line systems. A bundle comprises mechanically coupled stereocilia, whose displacements in response to stimulation activate a receptor current. The similarity of stereociliary displacements within a bundle regulates fundamental properties of the receptor current like its speed, magnitude, and sensitivity. However, the dynamics of individual stereocilia from the mammalian cochlea in response to a known bundle stimulus has not been quantified. We developed a novel high-speed system, which dynamically stimulates and tracks individual inner-hair-cell stereocilia from male and female rats. Stimulating two to three of the tallest stereocilia within a bundle (nonuniform stimulation) caused dissimilar stereociliary displacements. Stereocilia farther from the stimulator moved less, but with little delay, implying that there is little slack in the system. Along the axis of mechanical sensitivity, stereocilium displacements peaked and reversed direction in response to a step stimulus. A viscoelastic model explained the observed displacement dynamics, which implies that coupling between the tallest stereocilia is effectively viscoelastic. Coupling elements between the tallest inner-hair-cell stereocilia were two to three times stronger than elements anchoring stereocilia to the surface of the cell but were 100-10,000 times weaker than those of a well-studied noncochlear hair bundle. Coupling was too weak to ensure that stereocilia move similarly in response to nonuniform stimulation at auditory frequencies. Our results imply that more uniform stimulation across the tallest stereocilia of an inner-hair-cell bundle in vivo is required to ensure stereociliary displacement similarity, increasing the speed, sensitivity, and magnitude of the receptor current.SIGNIFICANCE STATEMENT Generation of the receptor current of the hair cell is the first step in electrically encoding auditory information in the hearing organs of all vertebrates. The receptor current is shaped by mechanical coupling between stereocilia in the hair bundle of each hair cell. Here, we provide foundational information on the mechanical coupling between stereocilia of cochlear inner-hair cells. In contrast to other types of hair cell, coupling between inner-hair-cell stereocilia is weak, causing slower, smaller, and less sensitive receptor currents in response to stimulation of few, rather than many, stereocilia. Our results imply that inner-hair cells need many stereocilia to be stimulated in vivo to ensure fast, large, and sensitive receptor currents.
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Affiliation(s)
| | | | - Anthony J Ricci
- Department of Otolaryngology
- Neuroscience Graduate Program
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305
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41
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Qiu X, Liang X, Llongueras JP, Cunningham C, Müller U. The tetraspan LHFPL5 is critical to establish maximal force sensitivity of the mechanotransduction channel of cochlear hair cells. Cell Rep 2023; 42:112245. [PMID: 36917610 DOI: 10.1016/j.celrep.2023.112245] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 01/28/2023] [Accepted: 02/27/2023] [Indexed: 03/14/2023] Open
Abstract
The mechanoelectrical transduction (MET) channel of cochlear hair cells is gated by the tip link, but the mechanisms that establish the exquisite force sensitivity of this MET channel are not known. Here, we show that the tetraspan lipoma HMGIC fusion partner-like 5 (LHFPL5) directly couples the tip link to the MET channel. Disruption of these interactions severely perturbs MET. Notably, the N-terminal cytoplasmic domain of LHFPL5 binds to an amphipathic helix in TMC1, a critical gating domain conserved between different MET channels. Mutations in the amphipathic helix of TMC1 or in the N-terminus of LHFPL5 that perturb interactions of LHFPL5 with the amphipathic helix affect channel responses to mechanical force. We conclude that LHFPL5 couples the tip link to the MET channel and that channel gating depends on a structural element in TMC1 that is evolutionarily conserved between MET channels. Overall, our findings support a tether model for transduction channel gating by the tip link.
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Chatterjee P, Morgan CP, Krey JF, Benson C, Goldsmith J, Bateschell M, Ricci AJ, Barr-Gillespie PG. GIPC3 couples to MYO6 and PDZ domain proteins and shapes the hair cell apical region. bioRxiv 2023:2023.02.28.530466. [PMID: 36909580 PMCID: PMC10002731 DOI: 10.1101/2023.02.28.530466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Abstract
GIPC3 has been implicated in auditory function. Initially localized to the cytoplasm of inner and outer hair cells of the cochlea, GIPC3 increasingly concentrated in cuticular plates and at cell junctions during postnatal development. Early postnatal Gipc3 KO/KO mice had mostly normal mechanotransduction currents, but had no auditory brainstem response at one month of age. Cuticular plates of Gipc3 KO/KO hair cells did not flatten during development as did those of controls; moreover, hair bundles were squeezed along the cochlear axis in mutant hair cells. Junctions between inner hair cells and adjacent inner phalangeal cells were also severely disrupted in Gipc3 KO/KO cochleas. GIPC3 bound directly to MYO6, and the loss of MYO6 led to altered distribution of GIPC3. Immunoaffinity purification of GIPC3 from chicken inner ear extracts identified co-precipitating proteins associated with adherens junctions, intermediate filament networks, and the cuticular plate. Several of immunoprecipitated proteins contained GIPC-family consensus PDZ binding motifs (PBMs), including MYO18A, which binds directly to the PDZ domain of GIPC3. We propose that GIPC3 and MYO6 couple to PBMs of cytoskeletal and cell-junction proteins to shape the cuticular plate. Summary statement The PDZ-domain protein GIPC3 couples the molecular motors MYO6 and MYO18A to actin cytoskeleton structures in hair cells. GIPC3 is necessary for shaping the hair cell’s cuticular plate and hence the arrangement of the stereocilia in the hair bundle.
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Affiliation(s)
- Paroma Chatterjee
- Oregon Hearing Research Center & Vollum Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Clive P. Morgan
- Oregon Hearing Research Center & Vollum Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Jocelyn F. Krey
- Oregon Hearing Research Center & Vollum Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Connor Benson
- Oregon Hearing Research Center & Vollum Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Jennifer Goldsmith
- Oregon Hearing Research Center & Vollum Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Michael Bateschell
- Oregon Hearing Research Center & Vollum Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Anthony J. Ricci
- Department of Otolaryngology—Head & Neck Surgery, Stanford University, Stanford, California 94305, USA ss
| | - Peter G. Barr-Gillespie
- Oregon Hearing Research Center & Vollum Institute, Oregon Health & Science University, Portland, Oregon, USA
- Manuscript correspondence at
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Poppi LA, Bigland MJ, Cresswell ET, Tabatabaee H, Lorincz D, Drury HR, Callister RJ, Holt JC, Lim R, Brichta AM, Smith DW. Molecular and functional changes to postsynaptic cholinergic signaling in the vestibular sensory organs of aging C57BL/6 mice. J Gerontol A Biol Sci Med Sci 2023:7058229. [PMID: 36840917 DOI: 10.1093/gerona/glad067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Indexed: 02/26/2023] Open
Abstract
Cholinergic circuits in the central nervous system are vulnerable to age-related functional decline, but it is not known if aging impacts cholinergic signaling in the vestibular sensory organs, which are critically important to balance maintenance and visual gaze stability. We have previously shown cholinergic neurotransmission between vestibular efferent terminals and type II mechanosensory hair cells requires the alpha9 (Chrna9) nicotinic receptor subunit. Homozygous knockout of the alpha9 subunit causes vestibulo-ocular reflex adaptation deficits that mirror those observed in aged mice. This prompted examination of cholinergic signaling in the vestibular sensory organs of aged mice. We confirmed older (>24 months) mice had impaired performance in a balance beam task compared to young (3-4 months) adult mice. While there was no qualitative loss of cholinergic axon varicosities in the crista ampullaris of old mice, qPCR analysis revealed reduced expression of nicotinic receptor subunit genes Chrna1, Chrna9, and Chrna10 in the cristae of old relative to young mice. Functionally, single-cell patch clamp recordings taken from type II vestibular hair cells exposed to acetylcholine show reduced conductance through alpha9/10 subunit-containing nicotinic receptors in older mice, despite preserved passive membrane properties and voltage-activated conductances. These findings suggest that cholinergic signaling in the peripheral vestibular sensory organs is vulnerable to aging processes, manifesting in dynamic molecular and functional age-related changes. Given the importance of these organs to our everyday activities, and the dramatic increase in fall incidence in the elderly, further investigation into the mechanisms of altered peripheral vestibular function in older humans is warranted.
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Affiliation(s)
- Lauren A Poppi
- Neurobiology of Ageing and Dementia Laboratory, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Newcastle, NSW, Australia.,Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Mark J Bigland
- Neurobiology of Ageing and Dementia Laboratory, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Newcastle, NSW, Australia.,Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Ethan T Cresswell
- Neurobiology of Ageing and Dementia Laboratory, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Newcastle, NSW, Australia.,Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Hessam Tabatabaee
- Neurobiology of Ageing and Dementia Laboratory, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Newcastle, NSW, Australia.,Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - David Lorincz
- Neurobiology of Ageing and Dementia Laboratory, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Newcastle, NSW, Australia.,Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Hannah R Drury
- Neurobiology of Ageing and Dementia Laboratory, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Newcastle, NSW, Australia.,Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Robert J Callister
- Neurobiology of Ageing and Dementia Laboratory, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Newcastle, NSW, Australia.,Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Joseph C Holt
- Department of Otolaryngology, University of Rochester Medical Centre, Rochester, NY, USA
| | - Rebecca Lim
- Neurobiology of Ageing and Dementia Laboratory, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Newcastle, NSW, Australia.,Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Alan M Brichta
- Neurobiology of Ageing and Dementia Laboratory, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Newcastle, NSW, Australia.,Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Doug W Smith
- Neurobiology of Ageing and Dementia Laboratory, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Newcastle, NSW, Australia.,Hunter Medical Research Institute, Newcastle, NSW, Australia
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Carlton AJ, Jeng J, Grandi FC, De Faveri F, Ceriani F, De Tomasi L, Underhill A, Johnson SL, Legan KP, Kros CJ, Richardson GP, Mustapha M, Marcotti W. A critical period of prehearing spontaneous Ca 2+ spiking is required for hair-bundle maintenance in inner hair cells. EMBO J 2023; 42:e112118. [PMID: 36594367 PMCID: PMC9929643 DOI: 10.15252/embj.2022112118] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 11/22/2022] [Accepted: 11/28/2022] [Indexed: 01/04/2023] Open
Abstract
Sensory-independent Ca2+ spiking regulates the development of mammalian sensory systems. In the immature cochlea, inner hair cells (IHCs) fire spontaneous Ca2+ action potentials (APs) that are generated either intrinsically or by intercellular Ca2+ waves in the nonsensory cells. The extent to which either or both of these Ca2+ signalling mechansims are required for IHC maturation is unknown. We find that intrinsic Ca2+ APs in IHCs, but not those elicited by Ca2+ waves, regulate the maturation and maintenance of the stereociliary hair bundles. Using a mouse model in which the potassium channel Kir2.1 is reversibly overexpressed in IHCs (Kir2.1-OE), we find that IHC membrane hyperpolarization prevents IHCs from generating intrinsic Ca2+ APs but not APs induced by Ca2+ waves. Absence of intrinsic Ca2+ APs leads to the loss of mechanoelectrical transduction in IHCs prior to hearing onset due to progressive loss or fusion of stereocilia. RNA-sequencing data show that pathways involved in morphogenesis, actin filament-based processes, and Rho-GTPase signaling are upregulated in Kir2.1-OE mice. By manipulating in vivo expression of Kir2.1 channels, we identify a "critical time period" during which intrinsic Ca2+ APs in IHCs regulate hair-bundle function.
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Affiliation(s)
| | - Jing‐Yi Jeng
- School of BiosciencesUniversity of SheffieldSheffieldUK
| | | | | | | | | | | | - Stuart L Johnson
- School of BiosciencesUniversity of SheffieldSheffieldUK
- Neuroscience InstituteUniversity of SheffieldSheffieldUK
| | - Kevin P Legan
- School of Life SciencesUniversity of Sussex, FalmerBrightonUK
| | - Corné J Kros
- School of Life SciencesUniversity of Sussex, FalmerBrightonUK
| | | | - Mirna Mustapha
- School of BiosciencesUniversity of SheffieldSheffieldUK
- Neuroscience InstituteUniversity of SheffieldSheffieldUK
| | - Walter Marcotti
- School of BiosciencesUniversity of SheffieldSheffieldUK
- Neuroscience InstituteUniversity of SheffieldSheffieldUK
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Giunta R, Cheli G, Spaiardi P, Russo G, Masetto S. Pimozide Increases a Delayed Rectifier K + Conductance in Chicken Embryo Vestibular Hair Cells. Biomedicines 2023; 11:biomedicines11020488. [PMID: 36831024 PMCID: PMC9953418 DOI: 10.3390/biomedicines11020488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/31/2023] [Accepted: 02/02/2023] [Indexed: 02/11/2023] Open
Abstract
Pimozide is a conventional antipsychotic drug largely used in the therapy for schizophrenia and Tourette's syndrome. Pimozide is assumed to inhibit synaptic transmission at the CNS by acting as a dopaminergic D2 receptor antagonist. Moreover, pimozide has been shown to block voltage-gated Ca2+ and K+ channels in different cells. Despite its widespread clinical use, pimozide can cause several adverse effects, including extrapyramidal symptoms and cardiac arrhythmias. Dizziness and loss of balance are among the most common side effects of pimozide. By using the patch-clamp whole-cell technique, we investigated the effect of pimozide [3 μM] on K+ channels expressed by chicken embryo vestibular type-II hair cells. We found that pimozide slightly blocks a transient outward rectifying A-type K+ current but substantially increases a delayed outward rectifying K+ current. The net result was a significant hyperpolarization of type-II hair cells at rest and a strong reduction of their response to depolarizing stimuli. Our findings are consistent with an inhibitory effect of pimozide on the afferent synaptic transmission by type-II hair cells. Moreover, they provide an additional key to understanding the beneficial/collateral pharmacological effects of pimozide. The finding that pimozide can act as a K+ channel opener provides a new perspective for the use of this drug.
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Affiliation(s)
- Roberta Giunta
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy
| | - Giulia Cheli
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy
| | - Paolo Spaiardi
- Department of Biology and Biotechnology, University of Pavia, 27100 Pavia, Italy
| | - Giancarlo Russo
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy
| | - Sergio Masetto
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy
- Correspondence:
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Zhao J, Yin N, Li GL. Comparative study of ionic currents and exocytosis in hair cells of the basilar and amphibian papilla in bullfrogs. Front Cell Neurosci 2023; 16:1064886. [PMID: 36700157 PMCID: PMC9868640 DOI: 10.3389/fncel.2022.1064886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Accepted: 12/13/2022] [Indexed: 01/11/2023] Open
Abstract
Hearing organs in the peripheral of different vertebrate species are extremely diverse in shape and function. In particular, while the basilar papilla (BP) is elongated and covers the sounds of both low and high frequencies in turtles and birds, it is round and responds to high frequencies only in frogs, leaving the low frequencies to the amphibian papilla (AP). In this study, we performed patch-clamp recordings in hair cells of both hearing organs in bullfrogs and conducted a comparative study of their ionic currents and exocytosis. Compared to hair cells in AP with a large tetraethylammonium (TEA)-sensitive slow-activating K+ current (I K), those in BP exhibited a small 4-aminopyridine (4-AP)-sensitive fast-inactivating K+ current (I A). Furthermore, hair cells in BP exhibited a significantly smaller Ca2+ current with a more positive half-activation voltage (Vhalf) and a slower slope of voltage dependency (k). In response to step depolarization, exocytosis (ΔCm) in BP hair cells was also significantly smaller, but the Ca2+ efficiency, assessed with the ratio between ΔCm and Ca2+ charge (QCa), was comparable to that of AP hair cells. Finally, we applied a paired-step depolarization and varied the interval in between, and we found that the replenishment of synaptic vesicles was significantly slower in BP hair cells. Together, our findings suggest that hair cells tuned to high frequencies in bullfrogs release less synaptic vesicles and recycle synaptic vesicles more slowly, allowing them to cope well with the large DC component found in their receptor potentials in vivo.
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Affiliation(s)
- Jingjing Zhao
- ENT Institute and Department of Otorhinolaryngology, Eye and ENT Hospital, Fudan University, Shanghai, China
| | - Ning Yin
- ENT Institute and Department of Otorhinolaryngology, Eye and ENT Hospital, Fudan University, Shanghai, China
| | - Geng-Lin Li
- ENT Institute and Department of Otorhinolaryngology, Eye and ENT Hospital, Fudan University, Shanghai, China,NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, China,State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China,*Correspondence: Geng-Lin Li,
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Shi T, Beaulieu MO, Saunders LM, Fabian P, Trapnell C, Segil N, Crump JG, Raible DW. Single-cell transcriptomic profiling of the zebrafish inner ear reveals molecularly distinct hair cell and supporting cell subtypes. eLife 2023; 12:82978. [PMID: 36598134 PMCID: PMC9851615 DOI: 10.7554/elife.82978] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 01/04/2023] [Indexed: 01/05/2023] Open
Abstract
A major cause of human deafness and vestibular dysfunction is permanent loss of the mechanosensory hair cells of the inner ear. In non-mammalian vertebrates such as zebrafish, regeneration of missing hair cells can occur throughout life. While a comparative approach has the potential to reveal the basis of such differential regenerative ability, the degree to which the inner ears of fish and mammals share common hair cells and supporting cell types remains unresolved. Here, we perform single-cell RNA sequencing of the zebrafish inner ear at embryonic through adult stages to catalog the diversity of hair cells and non-sensory supporting cells. We identify a putative progenitor population for hair cells and supporting cells, as well as distinct hair and supporting cell types in the maculae versus cristae. The hair cell and supporting cell types differ from those described for the lateral line system, a distributed mechanosensory organ in zebrafish in which most studies of hair cell regeneration have been conducted. In the maculae, we identify two subtypes of hair cells that share gene expression with mammalian striolar or extrastriolar hair cells. In situ hybridization reveals that these hair cell subtypes occupy distinct spatial domains within the three macular organs, the utricle, saccule, and lagena, consistent with the reported distinct electrophysiological properties of hair cells within these domains. These findings suggest that primitive specialization of spatially distinct striolar and extrastriolar hair cells likely arose in the last common ancestor of fish and mammals. The similarities of inner ear cell type composition between fish and mammals validate zebrafish as a relevant model for understanding inner ear-specific hair cell function and regeneration.
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Affiliation(s)
- Tuo Shi
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - Marielle O Beaulieu
- Department of Otolaryngology-Head and Neck Surgery, University of WashingtonSeattleUnited States
| | - Lauren M Saunders
- Department of Genome Sciences, University of WashingtonSeattleUnited States
| | - Peter Fabian
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - Cole Trapnell
- Department of Genome Sciences, University of WashingtonSeattleUnited States
| | - Neil Segil
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - J Gage Crump
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - David W Raible
- Department of Otolaryngology-Head and Neck Surgery, University of WashingtonSeattleUnited States
- Department of Genome Sciences, University of WashingtonSeattleUnited States
- Department of Biological Structure, University of WashingtonSeattleUnited States
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Wang X, Fan Q, Yu X, Wang Y. Cellular distribution of the Fragile X mental retardation protein in the inner ear: a developmental and comparative study in the mouse, rat, gerbil, and chicken. J Comp Neurol 2023; 531:149-169. [PMID: 36222577 PMCID: PMC9691623 DOI: 10.1002/cne.25420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 09/08/2022] [Accepted: 09/16/2022] [Indexed: 11/11/2022]
Abstract
The Fragile X mental retardation protein (FMRP) is an mRNA binding protein that is essential for neural circuit assembly and synaptic plasticity. Loss of functional FMRP leads to Fragile X syndrome (FXS), a neurodevelopmental disorder characterized by sensory dysfunction including abnormal auditory processing. While the central mechanisms of FMRP regulation have been studied in the brain, whether FMRP is expressed in the auditory periphery and how it develops and functions remains unknown. In this study, we characterized the spatiotemporal distribution pattern of FMRP immunoreactivity in the inner ear of mice, rats, gerbils, and chickens. Across species, FMRP was expressed in hair cells and supporting cells, with a particularly high level in immature hair cells during the prehearing period. Interestingly, the distribution of cytoplasmic FMRP displayed an age-dependent translocation in hair cells, and this feature was conserved across species. In the auditory ganglion (AG), FMRP immunoreactivity was detected in neuronal cell bodies as well as their peripheral and central processes. Distinct from hair cells, FMRP intensity in AG neurons was high both during development and after maturation. Additionally, FMRP was evident in mature glial cells surrounding AG neurons. Together, these observations demonstrate distinct developmental trajectories across cell types in the auditory periphery. Given the importance of peripheral inputs to the maturation of auditory circuits, these findings implicate involvement of FMRP in inner ear development as well as a potential contribution of periphery FMRP to the generation of auditory dysfunction in FXS.
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Affiliation(s)
- Xiaoyu Wang
- Division of Histology & Embryology, Key Laboratory for Regenerative Medicine of the Ministry of Education, College of Medicine, Jinan University, Guangzhou 510632, China
- Program in Neuroscience, Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306, USA
| | - Qiwei Fan
- Division of Histology & Embryology, Key Laboratory for Regenerative Medicine of the Ministry of Education, College of Medicine, Jinan University, Guangzhou 510632, China
| | - Xiaoyan Yu
- Program in Neuroscience, Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306, USA
| | - Yuan Wang
- Program in Neuroscience, Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306, USA
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Xia M, Ma J, Wu M, Guo L, Chen Y, Li GL, Sun S, Chai R, Li H, Li W. Generation of innervated cochlear organoid recapitulates early development of auditory unit. Stem Cell Reports 2023; 18:319-36. [PMID: 36584686 DOI: 10.1016/j.stemcr.2022.11.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [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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James B, Piekarz P, Moya-Díaz J, Lagnado L. The Impact of Multivesicular Release on the Transmission of Sensory Information by Ribbon Synapses. J Neurosci 2022; 42:9401-14. [PMID: 36344266 DOI: 10.1523/JNEUROSCI.0717-22.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 10/01/2022] [Accepted: 10/06/2022] [Indexed: 11/09/2022] Open
Abstract
The statistics of vesicle release determine how synapses transfer information, but the classical Poisson model of independent release does not always hold at the first stages of vision and hearing. There, ribbon synapses also encode sensory signals as events comprising two or more vesicles released simultaneously. The implications of such coordinated multivesicular release (MVR) for spike generation are not known. Here we investigate how MVR alters the transmission of sensory information compared with Poisson synapses using a pure rate-code. We used leaky integrate-and-fire models incorporating the statistics of release measured experimentally from glutamatergic synapses of retinal bipolar cells in zebrafish (both sexes) and compared these with models assuming Poisson inputs constrained to operate at the same average rates. We find that MVR can increase the number of spikes generated per vesicle while reducing interspike intervals and latency to first spike. The combined effect was to increase the efficiency of information transfer (bits per vesicle) over a range of conditions mimicking target neurons of different size. MVR was most advantageous in neurons with short time constants and reliable synaptic inputs, when less convergence was required to trigger spikes. In the special case of a single input driving a neuron, as occurs in the auditory system of mammals, MVR increased information transfer whenever spike generation required more than one vesicle. This study demonstrates how presynaptic integration of vesicles by MVR can increase the efficiency with which sensory information is transmitted compared with a rate-code described by Poisson statistics.SIGNIFICANCE STATEMENT Neurons communicate by the stochastic release of vesicles at the synapse and the statistics of this process will determine how information is represented by spikes. The classical model is that vesicles are released independently by a Poisson process, but this does not hold at ribbon-type synapses specialized to transmit the first electrical signals in vision and hearing, where two or more vesicles can fuse in a single event by a process termed coordinated multivesicular release. This study shows that multivesicular release can increase the number of spikes generated per vesicle and the efficiency of information transfer (bits per vesicle) over a range of conditions found in the retina and peripheral auditory system.
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