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Vincent PFY, Young ED, Edge ASB, Glowatzki E. Auditory hair cells and spiral ganglion neurons regenerate synapses with refined release properties in vitro. Proc Natl Acad Sci U S A 2024; 121:e2315599121. [PMID: 39058581 DOI: 10.1073/pnas.2315599121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Accepted: 06/12/2024] [Indexed: 07/28/2024] Open
Abstract
Ribbon synapses between inner hair cells (IHCs) and type I spiral ganglion neurons (SGNs) in the inner ear are damaged by noise trauma and with aging, causing "synaptopathy" and hearing loss. Cocultures of neonatal denervated organs of Corti and newly introduced SGNs have been developed to find strategies for improving IHC synapse regeneration, but evidence of the physiological normality of regenerated synapses is missing. This study utilizes IHC optogenetic stimulation and SGN recordings, showing that, when P3-5 denervated organs of Corti are cocultured with SGNs, newly formed IHC/SGN synapses are indeed functional, exhibiting glutamatergic excitatory postsynaptic currents. When using older organs of Corti at P10-11, synaptic activity probed by deconvolution showed more mature release properties, closer to the specialized mode of IHC synaptic transmission crucial for coding the sound signal. This functional assessment of newly formed IHC synapses developed here, provides a powerful tool for testing approaches to improve synapse regeneration.
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Affiliation(s)
- Philippe F Y Vincent
- The Center for Hearing and Balance, The Johns Hopkins School of Medicine, Baltimore, MD 21205
- Department of Otolaryngology Head and Neck Surgery, The Johns Hopkins School of Medicine, Baltimore, MD 21205
| | - Eric D Young
- The Center for Hearing and Balance, The Johns Hopkins School of Medicine, Baltimore, MD 21205
- Department of Otolaryngology Head and Neck Surgery, The Johns Hopkins School of Medicine, Baltimore, MD 21205
- Department of Neuroscience, The Johns Hopkins School of Medicine, Baltimore, MD 21205
- Department of Biomedical Engineering, The Johns Hopkins School of Medicine, Baltimore, MD 21205
| | - Albert S B Edge
- Department of Otolaryngology, Harvard Medical School, Boston, MA 02115
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear, Boston, MA 02114
- Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, MA 02115
- Harvard Stem Cell Institute, Cambridge, MA 02139
| | - Elisabeth Glowatzki
- The Center for Hearing and Balance, The Johns Hopkins School of Medicine, Baltimore, MD 21205
- Department of Otolaryngology Head and Neck Surgery, The Johns Hopkins School of Medicine, Baltimore, MD 21205
- Department of Neuroscience, The Johns Hopkins School of Medicine, Baltimore, MD 21205
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Vincent PF, Young ED, Edge AS, Glowatzki E. Auditory Hair Cells and Spiral Ganglion Neurons Regenerate Synapses with Refined Release Properties In Vitro. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.05.561095. [PMID: 38076928 PMCID: PMC10705289 DOI: 10.1101/2023.10.05.561095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Ribbon synapses between inner hair cells (IHCs) and type I spiral ganglion neurons (SGNs) in the inner ear are damaged by noise trauma and with aging, causing 'synaptopathy 'and hearing loss. Co-cultures of neonatal denervated organs of Corti and newly introduced SGNs have been developed to find strategies for improving IHC synapse regeneration, but evidence of the physiological normality of regenerated synapses is missing. This study utilizes IHC optogenetic stimulation and SGN recordings, showing that newly formed IHC synapses are indeed functional, exhibiting glutamatergic excitatory postsynaptic currents. When older organs of Corti were plated, synaptic activity probed by deconvolution, showed more mature release properties, closer to the highly specialized mode of IHC synaptic transmission that is crucial for coding the sound signal. This newly developed functional assessment of regenerated IHC synapses provides a powerful tool for testing approaches to improve synapse regeneration.
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Affiliation(s)
- Philippe F.Y. Vincent
- The Center for Hearing and Balance, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Otolaryngology Head and Neck Surgery, The Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Eric D. Young
- The Center for Hearing and Balance, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Otolaryngology Head and Neck Surgery, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Neuroscience, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Biomedical Engineering, The Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Albert S.B. Edge
- Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, USA
- Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, Massachusetts, USA
- Harvard Stem Cell Institute, Cambridge, Massachusetts, USA
| | - Elisabeth Glowatzki
- The Center for Hearing and Balance, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Otolaryngology Head and Neck Surgery, The Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Neuroscience, The Johns Hopkins School of Medicine, Baltimore, Maryland
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Protection of Cochlear Ribbon Synapses and Prevention of Hidden Hearing Loss. Neural Plast 2020; 2020:8815990. [PMID: 33204247 PMCID: PMC7652619 DOI: 10.1155/2020/8815990] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 10/08/2020] [Accepted: 10/21/2020] [Indexed: 01/21/2023] Open
Abstract
In the auditory system, ribbon synapses are vesicle-associated structures located between inner hair cells (IHCs) and spiral ganglion neurons that are implicated in the modulation of trafficking and fusion of synaptic vesicles at the presynaptic terminals. Synapse loss may result in hearing loss and difficulties with understanding speech in a noisy environment. This phenomenon happens without permanent hearing loss; that is, the cochlear synaptopathy is "hidden." Recent studies have reported that synapse loss might be critical in the pathogenesis of hidden hearing loss. A better understanding of the molecular mechanisms of the formation, structure, regeneration, and protection of ribbon synapses will assist in the design of potential therapeutic strategies. In this review, we describe and summarize the following aspects of ribbon synapses: (1) functional and structural features, (2) potential mechanisms of damage, (3) therapeutic research on protecting the synapses, and (4) the role of synaptic regeneration in auditory neuropathy and the current options for synapse rehabilitation.
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Tang PC, Hashino E, Nelson RF. Progress in Modeling and Targeting Inner Ear Disorders with Pluripotent Stem Cells. Stem Cell Reports 2020; 14:996-1008. [PMID: 32442531 PMCID: PMC7355141 DOI: 10.1016/j.stemcr.2020.04.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 04/21/2020] [Accepted: 04/22/2020] [Indexed: 12/12/2022] Open
Abstract
Sensorineural hearing loss and vestibular dysfunction are caused by damage to neurons and mechanosensitive hair cells, which do not regenerate to any clinically relevant extent in humans. Several protocols have been devised to direct pluripotent stem cells (PSCs) into inner ear hair cells and neurons, which display many properties of their native counterparts. The efficiency, reproducibility, and scalability of these protocols are enhanced by incorporating knowledge of inner ear development. Modeling human diseases in vitro through genetic manipulation of PSCs is already feasible, thereby permitting the elucidation of mechanistic understandings of a wide array of disease etiologies. Early studies on transplantation of PSC-derived otic progenitors have been successful in certain animal models, yet restoration of function and long-term cell survival remain unrealized. Through further research, PSC-based approaches will continue to revolutionize our understanding of inner ear biology and contribute to the development of therapeutic treatments for inner ear disorders.
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Affiliation(s)
- Pei-Ciao Tang
- 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
| | - Rick F Nelson
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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Organotypic Cocultures of Human Pluripotent Stem Cell Derived-Neurons with Mammalian Inner Ear Hair Cells and Cochlear Nucleus Slices. Stem Cells Int 2019; 2019:8419493. [PMID: 31827535 PMCID: PMC6886346 DOI: 10.1155/2019/8419493] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 08/29/2019] [Accepted: 09/21/2019] [Indexed: 11/27/2022] Open
Abstract
Stem cells have been touted as a source of potential replacement neurons for inner ear degeneration for almost two decades now; yet to date, there are few studies describing the use of human pluripotent stem cells (hPSCs) for this purpose. If stem cell therapies are to be used clinically, it is critical to validate the usefulness of hPSC lines in vitro and in vivo. Here, we present the first quantitative evidence that differentiated hPSC-derived neurons that innervate both the inner ear hair cells and cochlear nucleus neurons in coculture, with significantly more new synaptic contacts formed on target cell types. Nascent contacts between stem cells and hair cells were immunopositive for both synapsin I and VGLUT1, closely resembling expression of these puncta in endogenous postnatal auditory neurons and control cocultures. When hPSCs were cocultured with cochlear nucleus brainstem slice, significantly greater numbers of VGLUT1 puncta were observed in comparison to slice alone. New VGLUT1 puncta in cocultures with cochlear nucleus slice were not significantly different in size, only in quantity. This experimentation describes new coculture models for assessing auditory regeneration using well-characterised hPSC-derived neurons and highlights useful methods to quantify the extent of innervation on different cell types in the inner ear and brainstem.
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Chen J, Hong F, Zhang C, Li L, Wang C, Shi H, Fu Y, Wang J. Differentiation and transplantation of human induced pluripotent stem cell-derived otic epithelial progenitors in mouse cochlea. Stem Cell Res Ther 2018; 9:230. [PMID: 30157937 PMCID: PMC6116394 DOI: 10.1186/s13287-018-0967-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 07/12/2018] [Accepted: 08/01/2018] [Indexed: 12/24/2022] Open
Abstract
Background Inner ear hair cells as mechanoreceptors are extremely important for hearing. Defects in hair cells are a major cause of deafness. Induced pluripotent stem cells (iPSCs) are promising for regenerating inner ear hair cells and treating hearing loss. Here, we investigated migration, differentiation, and synaptic connections of transplanted otic epithelial progenitors (OEPs) derived from human iPSCs in mouse cochlea. Methods Human urinary cells isolated from a healthy donor were reprogramed to form iPSCs that were induced to differentiate into OEPs and hair cell-like cells. Immunocytochemistry, electrophysiological examination, and scanning electron microscopy were used to examine characteristics of induced hair cell-like cells. OEP-derived hair cell-like cells were cocultured with spiral ganglion neurons (SGNs), and the markers of synaptic connections were detected using immunocytochemistry and transmission electron microscope. In vivo, OEPs derived from iPSCs were transplanted into the cochlea of mice by injection through the round window. Migration, differentiation, and synaptic connections of transplanted cells were also examined by thin cochlear sectioning and immunohistochemistry. Results The induced hair cell-like cells displayed typical morphological characteristics and electrophysiological properties specific to inner hair cells. In vitro, OEP-derived hair cell-like cells formed synaptic connections with SGNs in coculture. In vivo, some of the transplanted cells migrated to the site of the resident hair cells in the organ of Corti, differentiated into hair cell-like cells, and formed synaptic connections with native SGNs. Conclusions We conclude that the transplantation of OEPs is feasible for the regeneration of hair cells. These results present a substantial reference for a cell-based therapy for the loss of hair cells.
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Affiliation(s)
- Jianling Chen
- Institute of Cell and Development, College of Life Sciences, Zi-Jin-Gang Campus of Zhejiang University, Room 307, No.866, Yuhangtang Road, Hangzhou, 310058, Zhejiang, China
| | - Fanfan Hong
- Institute of Cell and Development, College of Life Sciences, Zi-Jin-Gang Campus of Zhejiang University, Room 307, No.866, Yuhangtang Road, Hangzhou, 310058, Zhejiang, China
| | - Cui Zhang
- Institute of Cell and Development, College of Life Sciences, Zi-Jin-Gang Campus of Zhejiang University, Room 307, No.866, Yuhangtang Road, Hangzhou, 310058, Zhejiang, China
| | - Liang Li
- Institute of Cell and Development, College of Life Sciences, Zi-Jin-Gang Campus of Zhejiang University, Room 307, No.866, Yuhangtang Road, Hangzhou, 310058, Zhejiang, China
| | - Cuicui Wang
- Institute of Cell and Development, College of Life Sciences, Zi-Jin-Gang Campus of Zhejiang University, Room 307, No.866, Yuhangtang Road, Hangzhou, 310058, Zhejiang, China
| | - Haosong Shi
- Department of Otorhinolaryngology, the Sixth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Yong Fu
- Department of ENT, Head and Neck Surgery, the Children's Hospital, Zhejiang University School of Medicine, Zhejiang, China. .,Department of Otolaryngology, the Children Hospital, School of Medicine, Bin-Jiang Campus of Zhejiang University, No. 3333, Binsheng Road, Hangzhou, 310051, Zhejiang, China.
| | - Jinfu Wang
- Institute of Cell and Development, College of Life Sciences, Zi-Jin-Gang Campus of Zhejiang University, Room 307, No.866, Yuhangtang Road, Hangzhou, 310058, Zhejiang, China.
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Liu Z, Jiang Y, Li X, Hu Z. Embryonic Stem Cell-Derived Peripheral Auditory Neurons Form Neural Connections with Mouse Central Auditory Neurons In Vitro via the α2δ1 Receptor. Stem Cell Reports 2018; 11:157-170. [PMID: 29887365 PMCID: PMC6066995 DOI: 10.1016/j.stemcr.2018.05.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 05/07/2018] [Accepted: 05/08/2018] [Indexed: 01/21/2023] Open
Abstract
Integration of stem cell-derived neurons into the central nervous system (CNS) remains a challenge. A co-culture system is developed to understand whether mouse embryonic stem cell (ESC)-derived spiral ganglion neuron (SGN)-like cells (ESNs) synapse with native mouse cochlear nucleus (CN) neurons. A Cre system is used to generate Cop-GFP ESCs, which are induced into ESNs expressing features similar to auditory SGNs. Neural connections are observed between ESNs and CN neurons 4–6 days after co-culturing, which is stimulated by thrombospondin-1 (TSP1). Antagonist and loss-of-function small hairpin RNA studies indicate that the α2δ1 receptor is critical for TSP1-induced synaptogenesis effects. Newly generated synapse-like structures express pre- and post-synaptic proteins. Synaptic vesicle recycling, pair recording, and blocker electrophysiology suggest functional synaptic vesicles, transsynaptic activities, and formation of glutamatergic synapses. These results demonstrate the synaptogenesis capability of ESNs, which is important for pluripotent ESC-derived neurons to form functional synaptic connections to CNS neurons. Embryonic stem cell-derived neurons form functional synapses with CNS neurons Thrombospondin-1 stimulates stem cell-based synaptogenesis via the α2δ1 receptor A co-culture system is developed to study stem cell-based synapse formation Stem cell-based synaptogenesis exhibits functional synapse features
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Affiliation(s)
- Zhenjie Liu
- Department of Otolaryngology-HNS, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Yiyun Jiang
- Department of Otolaryngology-HNS, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Xiaoyang Li
- Department of Otolaryngology-HNS, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Zhengqing Hu
- Department of Otolaryngology-HNS, Wayne State University School of Medicine, Detroit, MI 48201, USA.
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Mammalian Cochlear Hair Cell Regeneration and Ribbon Synapse Reformation. Neural Plast 2016; 2016:2523458. [PMID: 28119785 PMCID: PMC5227174 DOI: 10.1155/2016/2523458] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 11/29/2016] [Accepted: 12/01/2016] [Indexed: 01/29/2023] Open
Abstract
Hair cells (HCs) are the sensory preceptor cells in the inner ear, which play an important role in hearing and balance. The HCs of organ of Corti are susceptible to noise, ototoxic drugs, and infections, thus resulting in permanent hearing loss. Recent approaches of HCs regeneration provide new directions for finding the treatment of sensor neural deafness. To have normal hearing function, the regenerated HCs must be reinnervated by nerve fibers and reform ribbon synapse with the dendrite of spiral ganglion neuron through nerve regeneration. In this review, we discuss the research progress in HC regeneration, the synaptic plasticity, and the reinnervation of new regenerated HCs in mammalian inner ear.
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Innervation of Cochlear Hair Cells by Human Induced Pluripotent Stem Cell-Derived Neurons In Vitro. Stem Cells Int 2016; 2016:1781202. [PMID: 26966437 PMCID: PMC4761396 DOI: 10.1155/2016/1781202] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 12/31/2015] [Indexed: 01/09/2023] Open
Abstract
Induced pluripotent stem cells (iPSCs) may serve as an autologous source of replacement neurons in the injured cochlea, if they can be successfully differentiated and reconnected with residual elements in the damaged auditory system. Here, we explored the potential of hiPSC-derived neurons to innervate early postnatal hair cells, using established in vitro assays. We compared two hiPSC lines against a well-characterized hESC line. After ten days' coculture in vitro, hiPSC-derived neural processes contacted inner and outer hair cells in whole cochlear explant cultures. Neural processes from hiPSC-derived neurons also made contact with hair cells in denervated sensory epithelia explants and expressed synapsin at these points of contact. Interestingly, hiPSC-derived neurons cocultured with hair cells at an early stage of differentiation formed synapses with a higher number of hair cells, compared to hiPSC-derived neurons cocultured at a later stage of differentiation. Notable differences in the innervation potentials of the hiPSC-derived neurons were also observed and variations existed between the hiPSC lines in their innervation efficiencies. Collectively, these data illustrate the promise of hiPSCs for auditory neuron replacement and highlight the need to develop methods to mitigate variabilities observed amongst hiPSC lines, in order to achieve reliable clinical improvements for patients.
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Gillespie LN, Richardson RT, Nayagam BA, Wise AK. Treating hearing disorders with cell and gene therapy. J Neural Eng 2015; 11:065001. [PMID: 25420002 DOI: 10.1088/1741-2560/11/6/065001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Hearing loss is an increasing problem for a substantial number of people and, with an aging population, the incidence and severity of hearing loss will become more significant over time. There are very few therapies currently available to treat hearing loss, and so the development of new therapeutic strategies for hearing impaired individuals is of paramount importance to address this unmet clinical need. Most forms of hearing loss are progressive in nature and therefore an opportunity exists to develop novel therapeutic approaches to slow or halt hearing loss progression, or even repair or replace lost hearing function. Numerous emerging technologies have potential as therapeutic options. This paper details the potential of cell- and gene-based therapies to provide therapeutic agents to protect sensory and neural cells from various insults known to cause hearing loss; explores the potential of replacing lost sensory and nerve cells using gene and stem cell therapy; and describes the considerations for clinical translation and the challenges that need to be overcome.
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Ishikawa M, Ohnishi H, Skerleva D, Sakamoto T, Yamamoto N, Hotta A, Ito J, Nakagawa T. Transplantation of neurons derived from human iPS cells cultured on collagen matrix into guinea-pig cochleae. J Tissue Eng Regen Med 2015. [PMID: 26205474 DOI: 10.1002/term.2072] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The present study examined the efficacy of a neural induction method for human induced pluripotent stem (iPS) cells to eliminate undifferentiated cells and to determine the feasibility of transplanting neurally induced cells into guinea-pig cochleae for replacement of spiral ganglion neurons (SGNs). A stepwise method for differentiation of human iPS cells into neurons was used. First, a neural induction method was established on Matrigel-coated plates; characteristics of cell populations at each differentiation step were assessed. Second, neural stem cells were differentiated into neurons on a three-dimensional (3D) collagen matrix, using the same protocol of culture on Matrigel-coated plates; neuron subtypes in differentiated cells on a 3D collagen matrix were examined. Then, human iPS cell-derived neurons cultured on a 3D collagen matrix were transplanted into intact guinea-pig cochleae, followed by histological analysis. In vitro analyses revealed successful induction of neural stem cells from human iPS cells, with no retention of undifferentiated cells expressing OCT3/4. After the neural differentiation of neural stem cells, approximately 70% of cells expressed a neuronal marker, 90% of which were positive for vesicular glutamate transporter 1 (VGLUT1). The expression pattern of neuron subtypes in differentiated cells on a 3D collagen matrix was identical to that of the differentiated cells on Matrigel-coated plates. In addition, the survival of transplant-derived neurons was achieved when inflammatory responses were appropriately controlled. Our preparation method for human iPS cell-derived neurons efficiently eliminated undifferentiated cells and contributed to the settlement of transplant-derived neurons expressing VGLUT1 in guinea-pig cochleae. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Masaaki Ishikawa
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Japan
| | - Hiroe Ohnishi
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Japan
| | - Desislava Skerleva
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Japan
| | - Tatsunori Sakamoto
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Japan
| | - Norio Yamamoto
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Japan
| | - Akitsu Hotta
- Centre for iPS Cell Research and Application, Kyoto University, Japan
| | - Juichi Ito
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Japan
| | - Takayuki Nakagawa
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Japan
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Wan G, Corfas G. No longer falling on deaf ears: mechanisms of degeneration and regeneration of cochlear ribbon synapses. Hear Res 2015; 329:1-10. [PMID: 25937135 DOI: 10.1016/j.heares.2015.04.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 04/01/2015] [Accepted: 04/20/2015] [Indexed: 01/02/2023]
Abstract
Cochlear ribbon synapses are required for the rapid and precise neural transmission of acoustic signals from inner hair cells to the spiral ganglion neurons. Emerging evidence suggests that damage to these synapses represents an important form of cochlear neuropathy that might be highly prevalent in sensorineural hearing loss. In this review, we discuss our current knowledge on how ribbon synapses are damaged by noise and during aging, as well as potential strategies to promote ribbon synapse regeneration for hearing restoration.
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Affiliation(s)
- Guoqiang Wan
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109, USA
| | - Gabriel Corfas
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109, USA.
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Taurine Enhances Excitability of Mouse Cochlear Neural Stem Cells by Selectively Promoting Differentiation of Glutamatergic Neurons Over GABAergic Neurons. Neurochem Res 2015; 40:924-31. [DOI: 10.1007/s11064-015-1546-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Revised: 02/14/2015] [Accepted: 02/19/2015] [Indexed: 12/31/2022]
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Ren HM, Ren J, Liu W. Recognition and control of the progression of age-related hearing loss. Rejuvenation Res 2014; 16:475-86. [PMID: 23915327 DOI: 10.1089/rej.2013.1435] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Recent breakthroughs have provided notable insights into both the pathogenesis and therapeutic strategies for age-related hearing loss (ARHL). Simultaneously, these breakthroughs enhance our knowledge about this neurodegenerative disease and raise the question of whether the disorder is preventable or even treatable. Discoveries relating to ARHL have revealed a unique link between ARHL and the underlying pathologies. Therefore, we need to better understand the pathogenesis or the mechanism of ARHL and learn how to take full advantage of various therapeutic strategies to prevent the progression of ARHL.
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Affiliation(s)
- Hong Miao Ren
- Department of Otolaryngology Head and Neck Surgery, the Second Xiangya Hospital, Central South University , Changsha, Hunan, P.R. China
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Hu Z, Ulfendahl M. The potential of stem cells for the restoration of auditory function in humans. Regen Med 2014; 8:309-18. [PMID: 23627825 DOI: 10.2217/rme.13.32] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hearing loss is one of the most common disabilities, affecting approximately 10% of the population. Hair cells and spiral ganglion neurons are usually damaged in most cases of hearing loss. Currently, there is virtually no biological approach to replace damaged hearing cells. Recent developments in stem cell technology provide new opportunities for the treatment of deafness. Two major strategies have been investigated: differentiation of endogenous stem cells into new hair cells; and introduction of exogenous cells into the inner ear to substitute injured hearing neurons. Although there is still a learning curve in stem cell-based replacement, the probability exists to utilize personalized stem cells to eventually provide a novel intervention for patients with deafness in future clinical research trials.
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Affiliation(s)
- Zhengqing Hu
- Department of Otolaryngology-HNS, Wayne State University, MI, USA.
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Sensational placodes: neurogenesis in the otic and olfactory systems. Dev Biol 2014; 389:50-67. [PMID: 24508480 PMCID: PMC3988839 DOI: 10.1016/j.ydbio.2014.01.023] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 01/27/2014] [Accepted: 01/28/2014] [Indexed: 11/22/2022]
Abstract
For both the intricate morphogenetic layout of the sensory cells in the ear and the elegantly radial arrangement of the sensory neurons in the nose, numerous signaling molecules and genetic determinants are required in concert to generate these specialized neuronal populations that help connect us to our environment. In this review, we outline many of the proteins and pathways that play essential roles in the differentiation of otic and olfactory neurons and their integration into their non-neuronal support structures. In both cases, well-known signaling pathways together with region-specific factors transform thickened ectodermal placodes into complex sense organs containing numerous, diverse neuronal subtypes. Olfactory and otic placodes, in combination with migratory neural crest stem cells, generate highly specialized subtypes of neuronal cells that sense sound, position and movement in space, odors and pheromones throughout our lives.
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Novozhilova E, Olivius P, Siratirakun P, Lundberg C, Englund-Johansson U. Neuronal differentiation and extensive migration of human neural precursor cells following co-culture with rat auditory brainstem slices. PLoS One 2013; 8:e57301. [PMID: 23505423 PMCID: PMC3591396 DOI: 10.1371/journal.pone.0057301] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Accepted: 01/21/2013] [Indexed: 11/18/2022] Open
Abstract
Congenital or acquired hearing loss is often associated with a progressive degeneration of the auditory nerve (AN) in the inner ear. The AN is composed of processes and axons of the bipolar spiral ganglion neurons (SGN), forming the connection between the hair cells in the inner ear cochlea and the cochlear nuclei (CN) in the brainstem (BS). Therefore, replacement of SGNs for restoring the AN to improve hearing function in patients who receive a cochlear implantation or have severe AN malfunctions is an attractive idea. A human neural precursor cell (HNPC) is an appropriate donor cell to investigate, as it can be isolated and expanded in vitro with maintained potential to form neurons and glia. We recently developed a post-natal rodent in vitro auditory BS slice culture model including the CN and the central part of the AN for initial studies of candidate cells. Here we characterized the survival, distribution, phenotypic differentiation, and integration capacity of HNPCs into the auditory circuitry in vitro. HNPC aggregates (spheres) were deposited adjacent to or on top of the BS slices or as a monoculture (control). The results demonstrate that co-cultured HNPCs compared to monocultures (1) survive better, (2) distribute over a larger area, (3) to a larger extent and in a shorter time-frame form mature neuronal and glial phenotypes. HNPC showed the ability to extend neurites into host tissue. Our findings suggest that the HNPC-BS slice co-culture is appropriate for further investigations on the integration capacity of HNPCs into the auditory circuitry.
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Affiliation(s)
- Ekaterina Novozhilova
- Division of Oto-Rhino-Laryngology and Head and Neck Surgery, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
- Center for Hearing and Communication Research, Karolinska University Hospital, Stockholm, Sweden
- Department of Clinical Neuroscience, Section of Otorhinolaryngology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
| | - Petri Olivius
- Department of ENT—Head and Neck Surgery, UHL, County Council of Östergötland, Linköping, Sweden
- Division of Oto-Rhino-Laryngology and Head and Neck Surgery, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
- Center for Hearing and Communication Research, Karolinska University Hospital, Stockholm, Sweden
- Department of Clinical Neuroscience, Section of Otorhinolaryngology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
- * E-mail:
| | - Piyaporn Siratirakun
- Center for Hearing and Communication Research, Karolinska University Hospital, Stockholm, Sweden
- Department of Clinical Neuroscience, Section of Otorhinolaryngology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
| | - Cecilia Lundberg
- CNS Gene Therapy Unit, Dept. of Experimental Medical Science, Lund University, Lund, Sweden
| | - Ulrica Englund-Johansson
- Department of Ophthalmology, Institution of Clinical Sciences in Lund, Lund University, Lund, Sweden
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Needham K, Minter RL, Shepherd RK, Nayagam BA. Challenges for stem cells to functionally repair the damaged auditory nerve. Expert Opin Biol Ther 2013; 13:85-101. [PMID: 23094991 PMCID: PMC3543850 DOI: 10.1517/14712598.2013.728583] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
INTRODUCTION In the auditory system, a specialized subset of sensory neurons are responsible for correctly relaying precise pitch and temporal cues to the brain. In individuals with severe-to-profound sensorineural hearing impairment these sensory auditory neurons can be directly stimulated by a cochlear implant, which restores sound input to the brainstem after the loss of hair cells. This neural prosthesis therefore depends on a residual population of functional neurons in order to function effectively. AREAS COVERED In severe cases of sensorineural hearing loss where the numbers of auditory neurons are significantly depleted, the benefits derived from a cochlear implant may be minimal. One way in which to restore function to the auditory nerve is to replace these lost neurons using differentiated stem cells, thus re-establishing the neural circuit required for cochlear implant function. Such a therapy relies on producing an appropriate population of electrophysiologically functional neurons from stem cells, and on these cells integrating and reconnecting in an appropriate manner in the deaf cochlea. EXPERT OPINION Here we review progress in the field to date, including some of the key functional features that stem cell-derived neurons would need to possess and how these might be enhanced using electrical stimulation from a cochlear implant.
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Affiliation(s)
- Karina Needham
- University of Melbourne, Department of Otolaryngology, East Melbourne, Australia.
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Gunewardene N, Dottori M, Nayagam BA. The convergence of cochlear implantation with induced pluripotent stem cell therapy. Stem Cell Rev Rep 2012; 8:741-54. [PMID: 21956409 DOI: 10.1007/s12015-011-9320-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
According to 2010 estimates from The National Institute on Deafness and other Communication Disorders, approximately 17% (36 million) American adults have reported some degree of hearing loss. Currently, the only clinical treatment available for those with severe-to-profound hearing loss is a cochlear implant, which is designed to electrically stimulate the auditory nerve in the absence of hair cells. Whilst the cochlear implant has been revolutionary in terms of providing hearing to the severe-to-profoundly deaf, there are variations in cochlear implant performance which may be related to the degree of degeneration of auditory neurons following hearing loss. Hence, numerous experimental studies have focused on enhancing the efficacy of cochlear implants by using neurotrophins to preserve the auditory neurons, and more recently, attempting to replace these dying cells with new neurons derived from stem cells. As a result, several groups are now investigating the potential for both embryonic and adult stem cells to replace the degenerating sensory elements in the deaf cochlea. Recent advances in our knowledge of stem cells and the development of induced pluripotency by Takahashi and Yamanaka in 2006, have opened a new realm of science focused on the use of induced pluripotent stem (iPS) cells for therapeutic purposes. This review will provide a broad overview of the potential benefits and challenges of using iPS cells in combination with a cochlear implant for the treatment of hearing loss, including differentiation of iPS cells into an auditory neural lineage and clinically relevant transplantation approaches.
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Affiliation(s)
- Niliksha Gunewardene
- Department of Otolaryngology, University of Melbourne, Melbourne, Victoria, Australia
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Nayagam BA, Edge AS, Needham K, Hyakumura T, Leung J, Nayagam DAX, Dottori M. An in vitro model of developmental synaptogenesis using cocultures of human neural progenitors and cochlear explants. Stem Cells Dev 2012; 22:901-12. [PMID: 23078657 DOI: 10.1089/scd.2012.0082] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
In mammals, the sensory hair cells and auditory neurons do not spontaneously regenerate and their loss results in permanent hearing impairment. Stem cell therapy is one emerging strategy that is being investigated to overcome the loss of sensory cells after hearing loss. To successfully replace auditory neurons, stem cell-derived neurons must be electrically active, capable of organized outgrowth of processes, and of making functional connections with appropriate tissues. We have developed an in vitro assay to test these parameters using cocultures of developing cochlear explants together with neural progenitors derived from human embryonic stem cells (hESCs). We found that these neural progenitors are electrically active and extend their neurites toward the sensory hair cells in cochlear explants. Importantly, this neurite extension was found to be significantly greater when neural progenitors were predifferentiated toward a neural crest-like lineage. When grown in coculture with hair cells only (denervated cochlear explants), stem cell-derived processes were capable of locating and growing along the hair cell rows in an en passant-like manner. Many presynaptic terminals (synapsin 1-positive) were observed between hair cells and stem cell-derived processes in vitro. These results suggest that differentiated hESC-derived neural progenitors may be useful for developing therapies directed at auditory nerve replacement, including complementing emerging hair cell regeneration therapies.
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Affiliation(s)
- Bryony A Nayagam
- Department of Otolaryngology, The University of Melbourne, Melbourne, Parkville, Australia.
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22
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Okano T, Kelley MW. Stem cell therapy for the inner ear: recent advances and future directions. Trends Amplif 2012; 16:4-18. [PMID: 22514095 DOI: 10.1177/1084713812440336] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In vertebrates, perception of sound, motion, and balance is mediated through mechanosensory hair cells located within the inner ear. In mammals, hair cells are only generated during a short period of embryonic development. As a result, loss of hair cells as a consequence of injury, disease, or genetic mutation, leads to permanent sensory deficits. At present, cochlear implantation is the only option for profound hearing loss. However, outcomes are still variable and even the best implant cannot provide the acuity of a biological ear. The recent emergence of stem cell technology has the potential to open new approaches for hair cell regeneration. The goal of this review is to summarize the current state of inner ear stem cell research from a viewpoint of its clinical application for inner ear disorders to illustrate how complementary studies have the potential to promote and refine stem cell therapies for inner ear diseases. The review initially discusses our current understanding of the genetic pathways that regulate hair cell formation from inner ear progenitors during normal development. Subsequent sections discuss the possible use of endogenous inner ear stem cells to induce repair as well as the initial studies aimed at transplanting stem cells into the ear.
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Nishimura K, Nakagawa T, Sakamoto T, Ito J. Fates of murine pluripotent stem cell-derived neural progenitors following transplantation into mouse cochleae. Cell Transplant 2012; 21:763-71. [PMID: 22305181 DOI: 10.3727/096368911x623907] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
This study evaluated the tumorigenesis risk of induced pluripotent stem (iPS) cells after transplantation into the cochlea. One mouse embryonic stem (ES) cell line and three mouse iPS cell lines, one derived from adult mouse tail-tip fibroblasts (TTFs) and two from mouse embryonic fibroblasts (MEFs), were neurally induced by stromal cell-inducing activity. Before transplantation, the efficiency of neural induction and the proportion of residual undifferentiated cells were evaluated using immunocytochemistry, and no significant differences were observed in the ratios of colonies expressing βIII tubulin, nestin, or octamer (Oct)3/4. Four weeks after transplantation into the cochleae of neonatal mice, the number of surviving transplants of TTF-derived iPS cells generated by retroviral infection was significantly higher than those of MEF-derived iPS cells generated by plasmid transfection. Teratoma formation was identified in one of five cochleae transplanted with TTF-derived iPS cells. However, no significant differences were found in the cell proliferation activity or the extent of differentiation into mature neurons among the cell lines. These findings emphasize the necessity of selecting appropriate iPS cell lines and developing methods to eliminate undifferentiated cells after neural induction, in order to establish safe iPS cell-based therapy for the inner ear.
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Affiliation(s)
- Koji Nishimura
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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He S, Yang J. Maturation of neurotransmission in the developing rat cochlea: immunohistochemical evidence from differential expression of synaptophysin and synaptobrevin 2. Eur J Histochem 2011; 55:e2. [PMID: 21556117 PMCID: PMC3167347 DOI: 10.4081/ejh.2011.e2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Revised: 10/31/2010] [Accepted: 11/12/2010] [Indexed: 01/08/2023] Open
Abstract
Synaptophysin and synaptobrevin 2 associate closely with packaging and storage of synaptic vesicles and transmitter release, and both play important roles in the development of rat cochlea. We examined the differential expression of synaptophysin and synaptobrevin 2 in the developing Sprague-Dawley rat cochlea, and investigated the relationship between their expression and auditory development. The expression of synaptophysin and synaptobrevin 2 was not observed in Kolliker's and Corti's organ at postnatal 1 day (P1) and P5, and the top turn of the cochlea at P10. Expression was detected in the outer spiral bundle (OSB), the inner spiral bundle (ISB), and the medial wall of the Deiters' cell of the cochlea at P14, and P28, and in the middle or the basal turn of Corti's organ at P10. Synaptobrevin 2 was expressed in the top of the inner hair cells (IHCs) in Corti's organ of both P14 and P28 rats. All spiral ganglion neurons (SGNs) were stained at all ages examined. The localization of synaptophysin and synaptobrevin 2 in the cochlea was closely associated with the distribution of nerve fibers and neural activity (the docking and release of synaptic vesicles). Synaptophysin and synaptobrevin 2 were expressed in a dynamic manner during the development of rat cochlea. Their expression differences during the development were in favor of the configuration course constructed between nerve endings and target cells. It also played a key role in the formation of the correct coding of auditory information during auditory system development.
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Affiliation(s)
- S He
- Department of Otorhinolaryngology-Head & Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University, China
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Appler JM, Goodrich LV. Connecting the ear to the brain: Molecular mechanisms of auditory circuit assembly. Prog Neurobiol 2011; 93:488-508. [PMID: 21232575 DOI: 10.1016/j.pneurobio.2011.01.004] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Revised: 12/09/2010] [Accepted: 01/03/2011] [Indexed: 12/21/2022]
Abstract
Our sense of hearing depends on precisely organized circuits that allow us to sense, perceive, and respond to complex sounds in our environment, from music and language to simple warning signals. Auditory processing begins in the cochlea of the inner ear, where sounds are detected by sensory hair cells and then transmitted to the central nervous system by spiral ganglion neurons, which faithfully preserve the frequency, intensity, and timing of each stimulus. During the assembly of auditory circuits, spiral ganglion neurons establish precise connections that link hair cells in the cochlea to target neurons in the auditory brainstem, develop specific firing properties, and elaborate unusual synapses both in the periphery and in the CNS. Understanding how spiral ganglion neurons acquire these unique properties is a key goal in auditory neuroscience, as these neurons represent the sole input of auditory information to the brain. In addition, the best currently available treatment for many forms of deafness is the cochlear implant, which compensates for lost hair cell function by directly stimulating the auditory nerve. Historically, studies of the auditory system have lagged behind other sensory systems due to the small size and inaccessibility of the inner ear. With the advent of new molecular genetic tools, this gap is narrowing. Here, we summarize recent insights into the cellular and molecular cues that guide the development of spiral ganglion neurons, from their origin in the proneurosensory domain of the otic vesicle to the formation of specialized synapses that ensure rapid and reliable transmission of sound information from the ear to the brain.
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Affiliation(s)
- Jessica M Appler
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
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Abstract
Sensory hair cells of the inner ear are responsible for translating auditory or vestibular stimuli into electrical energy that can be perceived by the nervous system. Although hair cells are exquisitely mechanically sensitive, they can be easily damaged by excessive stimulation by ototoxic drugs and by the effects of aging. In mammals, auditory hair cells are never replaced, such that cumulative damage to the ear causes progressive and permanent deafness. In contrast, non-mammalian vertebrates are capable of replacing lost hair cells, which has led to efforts to understand the molecular and cellular basis of regenerative responses in different vertebrate species. In this review, we describe recent progress in understanding the limits to hair cell regeneration in mammals and discuss the obstacles that currently exist for therapeutic approaches to hair cell replacement.
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Affiliation(s)
- Andrew K Groves
- Department of Neuroscience, Baylor College of Medicine, BCM 295, 1 Baylor Plaza, Houston, TX 77030, USA.
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Abstract
PURPOSE OF REVIEW This review will focus on 'self-repair' of the mammalian inner ear sensory epithelium, including recruiting the in-situ proliferation and differentiation of endogenous cells at the damaged site and the autologous transplantation RECENT FINDINGS Self-repair refers to a favorable structural and functional outcome of damaged inner ear sensory epithelium. Our advanced ability of manipulating the fate of inner ear sensory cells makes in-situ proliferation a possible candidate of hearing restoration. A practical alternative of the unavoidable immune rejection is to introduce autologous cells. Ependymal cells, induced pluripotent stem cells, and olfactory neuroepithelial cells have been recognized as promising sources, which will spur ongoing efforts to evaluate these new cell sources for cell replacement therapy. SUMMARY Further exploration of the innate advantages of in-situ proliferation and use of novel cell sources for autologous transplantation may serve as rehearsals for clinical trials in the near future.
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Abstract
This study examined the potential of induced pluripotent stem (iPS) cells for use as a source of transplants for the restoration of auditory spiral ganglion neurons. We monitored neurite outgrowth from iPS cell-derived neural progenitors toward cochlear hair cells ex vivo, and followed their survival and fates after transplantation into mouse cochleae in vivo. Neurons derived from iPS cells projected neurites toward cochlear hair cells. The settlement of iPS cell-derived neurons was observed 1 week after transplantation into the cochlea. Some transplants expressed vesicular glutamate transporter 1, which is a marker for glutamatergic neurons. These findings indicate that iPS cells can be used as a source of transplants for the regeneration of spiral ganglion neurons.
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Current world literature. Curr Opin Otolaryngol Head Neck Surg 2009; 17:412-8. [PMID: 19755872 DOI: 10.1097/moo.0b013e3283318f24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Glavaski-Joksimovic A, Thonabulsombat C, Wendt M, Eriksson M, Ma H, Olivius P. Morphological differentiation of tau–green fluorescent protein embryonic stem cells into neurons after co-culture with auditory brain stem slices. Neuroscience 2009; 162:472-81. [DOI: 10.1016/j.neuroscience.2009.04.070] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2009] [Revised: 04/12/2009] [Accepted: 04/28/2009] [Indexed: 01/29/2023]
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