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Anselmi C, Fuller GK, Stolfi A, Groves AK, Manni L. Sensory cells in tunicates: insights into mechanoreceptor evolution. Front Cell Dev Biol 2024; 12:1359207. [PMID: 38550380 PMCID: PMC10973136 DOI: 10.3389/fcell.2024.1359207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 03/04/2024] [Indexed: 04/04/2024] Open
Abstract
Tunicates, the sister group of vertebrates, offer a unique perspective for evolutionary developmental studies (Evo-Devo) due to their simple anatomical organization. Moreover, the separation of tunicates from vertebrates predated the vertebrate-specific genome duplications. As adults, they include both sessile and pelagic species, with very limited mobility requirements related mainly to water filtration. In sessile species, larvae exhibit simple swimming behaviors that are required for the selection of a suitable substrate on which to metamorphose. Despite their apparent simplicity, tunicates display a variety of mechanoreceptor structures involving both primary and secondary sensory cells (i.e., coronal sensory cells). This review encapsulates two decades of research on tunicate mechanoreception focusing on the coronal organ's sensory cells as prime candidates for understanding the evolution of vertebrate hair cells of the inner ear and the lateral line organ. The review spans anatomical, cellular and molecular levels emphasizing both similarity and differences between tunicate and vertebrate mechanoreception strategies. The evolutionary significance of mechanoreception is discussed within the broader context of Evo-Devo studies, shedding light on the intricate pathways that have shaped the sensory system in chordates.
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Affiliation(s)
- Chiara Anselmi
- Hopkins Marine Station, Institute for Stem Cell Biology and Regenerative Medicine, Stanford University, Pacific Grove, CA, United States
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, United States
| | - Gwynna K. Fuller
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Alberto Stolfi
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| | - Andrew K. Groves
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States
| | - Lucia Manni
- Dipartimento di Biologia, Università degli Studi di Padova, Padova, Italy
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2
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Li J, Yang J, Xia Y, Wang J, Xia Y. Effects of Astragaloside IV on Hearing, Inflammatory Factors, and Intestinal Flora in Mice Exposed to Noise. Metabolites 2024; 14:122. [PMID: 38393014 PMCID: PMC10890247 DOI: 10.3390/metabo14020122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/22/2024] [Accepted: 01/29/2024] [Indexed: 02/25/2024] Open
Abstract
Long-term exposure to noise can cause irreversible hearing loss. Considering that there is no effective drug treatment, it is important to seek preventive treatment for noise-induced hearing loss (NIHL). Although astragaloside IV (AS-IV) protects against NIHL by reducing serum inflammatory factors, there is scarce information on the regulation of inflammatory factors by AS-IV to prevent NIHL. We investigated the hearing thresholds and relationship between the serum levels of inflammatory cytokines and intestinal microbiota of c57bl/6j mice exposed to noise (103 dB SPL 4 h·d-1) for 7 days, treated with or without AS-IV. Our results revealed a lower hearing threshold and lower serum levels of TNF-α, TNF-γ, IL-6, IL-1β, and IFN-γ in the mice treated with AS-IV. Additionally, AS-IV increased the abundance levels of the phylum Firmicutes, class Bacillus, order Lactobacillus, and family Lactobacillus (p < 0.05), and decreased those of the phylum Bacteroidetes and order Bacteroidales (p < 0.05). Lactobacillus and Bacilli negatively correlated with TNF-α, TNF-γ, and IL-1β; Erysipelotrichaceae negatively correlated with INF-γ; and Clostridiales positively correlated with IL-1β. In conclusion, AS-IV reduces the elevation of hearing thresholds in mice, preventing hearing loss in mice exposed to noise, and under the intervention of AS-IV, changes in the levels of inflammatory factors correlate with intestinal flora. We suggest that AS-IV improves intestinal flora and reduces inflammation levels in c57bl/6j mice exposed to noise.
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Affiliation(s)
- Junyi Li
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou 510310, China
| | - Jian Yang
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou 510310, China
| | - Yun Xia
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou 510310, China
| | - Junyi Wang
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou 510310, China
| | - Yuan Xia
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou 510310, China
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3
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Zhao Y, Xu Z, Zhang R, Liu M, Lu C, Fan C, Wang J. Integrated scRNAseq analyses of mouse cochlear supporting cells reveal the involvement of Ezh2 in hair cell regeneration. Mol Biol Rep 2024; 51:217. [PMID: 38281217 DOI: 10.1007/s11033-023-09173-y] [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: 04/07/2023] [Accepted: 12/15/2023] [Indexed: 01/30/2024]
Abstract
BACKGROUND In lower vertebrates like fish, the inner ear and lateral line hair cells (HCs) can regenerate after being damaged by proliferation/differentiation of supporting cells (SCs). However, the HCs of mouse cochlear could only regenerate within one to two weeks after birth but not for adults. METHODS AND RESULTS To better understand the molecular foundations, we collected several public single-cell RNA sequencing (scRNAseq) data of mouse cochleae from E14 to P33 and extracted the prosensory and supporting cells specifically. Gene Set Enrichment Analysis (GSEA) results revealed a down-regulation of genes in Notch signaling pathway during postnatal stages (P7 and P33). We also identified 107 time-course co-expression genes correlated with developmental stage and predicated that EZH2 and KLF15 may be the key transcriptional regulators for these genes. Expressions of candidate target genes of EZH2 and KLF15 were also found in supporting cells of the auditory epithelia in chick and the neuromasts in zebrafish. Furthermore, inhibiting EZH2 suppressed regeneration of hair cells in zebrafish neuromasts and altered expressions of some developmental stage correlated genes. CONCLUSIONS Our results extended the understanding for molecular basis of hair cell regeneration ability and revealed the potential role of Ezh2 in it.
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Affiliation(s)
- Yifan Zhao
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai, China
- Institute for Marine Biosystem and Neuroscience, International Center for Marine Studies, Shanghai Ocean University, Shanghai, China
| | - Ze Xu
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai, China
- Institute for Marine Biosystem and Neuroscience, International Center for Marine Studies, Shanghai Ocean University, Shanghai, China
| | - Ran Zhang
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai, China
- Institute for Marine Biosystem and Neuroscience, International Center for Marine Studies, Shanghai Ocean University, Shanghai, China
| | - Mingli Liu
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, China
| | - Chengcheng Lu
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai, China
- Institute for Marine Biosystem and Neuroscience, International Center for Marine Studies, Shanghai Ocean University, Shanghai, China
- Shanghai Horizon Medical Technology Co. Ltd, Shanghai, China
| | - Chunxin Fan
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai, China.
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, China.
- Institute for Marine Biosystem and Neuroscience, International Center for Marine Studies, Shanghai Ocean University, Shanghai, China.
- Marine Biomedical Science and Technology Innovation Platform of Lingang New Area, Shanghai, China.
| | - Jian Wang
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai, China.
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, China.
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4
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Abstract
Orchestration of protein production and degradation and the regulation of protein lifetimes play a central role in many basic biological processes. Nearly all mammalian proteins are replenished by protein turnover in waves of synthesis and degradation. Protein lifetimes in vivo are typically measured in days, but a small number of extremely long-lived proteins (ELLPs) persist for months or even years. ELLPs are rare in all tissues but are enriched in tissues containing terminally differentiated post-mitotic cells and extracellular matrix. Consistently, emerging evidence suggests that the cochlea may be particularly enriched in ELLPs. Damage to ELLPs in specialized cell types, such as crystallin in the lens cells of the eye, causes organ failure such as cataracts. Similarly, damage to cochlear ELLPs is likely to occur with many insults, including acoustic overstimulation, drugs, anoxia, and antibiotics, and may play an underappreciated role in hearing loss. Furthermore, hampered protein degradation may contribute to acquired hearing loss. In this review, I highlight our knowledge of the lifetimes of cochlear proteins with an emphasis on ELLPs and the potential contribution that impaired cochlear protein degradation has on acquired hearing loss and the emerging relevance of ELLPs.
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Affiliation(s)
- Jeffrey N Savas
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
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5
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Smith-Cortinez N, Hendriksen FGJ, Ramekers D, Stokroos RJ, Versnel H, Straatman LV. Long-term survival of LGR5 expressing supporting cells after severe ototoxic trauma in the adult mouse cochlea. Front Cell Neurosci 2023; 17:1236894. [PMID: 37692553 PMCID: PMC10483136 DOI: 10.3389/fncel.2023.1236894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 08/07/2023] [Indexed: 09/12/2023] Open
Abstract
Introduction The leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5) is a tissue resident stem cell marker, which it is expressed in supporting cells (SCs) in the organ of Corti in the mammalian inner ear. These LGR5+ SCs can be used as an endogenous source of progenitor cells for regeneration of hair cells (HCs) to treat hearing loss and deafness. We have recently reported that LGR5+ SCs survive 1 week after ototoxic trauma. Here, we evaluated Lgr5 expression in the adult cochlea and long-term survival of LGR5+ SCs following severe hearing loss. Methods Lgr5GFP transgenic mice and wild type mice aged postnatal day 30 (P30) and P200 were used. P30 animals were deafened with a single dose of furosemide and kanamycin. Seven and 28 days after deafening, auditory brainstem responses (ABRs) were recorded. Cochleas were harvested to characterize mature HCs and LGR5+ SCs by immunofluorescence microscopy and quantitative reverse transcription PCR (q-RT-PCR). Results There were no significant age-related changes in Lgr5 expression when comparing normal-hearing (NH) mice aged P200 with P30. Seven and 28 days after ototoxic trauma, there was severe outer HC loss and LGR5 was expressed in the third row of Deiters' cells and in inner pillar cells. Seven days after induction of ototoxic trauma there was an up-regulation of the mRNA expression of Lgr5 compared to the NH condition; 28 days after ototoxic trauma Lgr5 expression was similar to NH levels. Discussion The presence of LGR5+ SCs in the adult mouse cochlea, which persists after severe HC loss, suggests potential regenerative capacity of endogenous cochlear progenitor cells in adulthood. To our knowledge, this is the first study showing not only long-term survival of LGR5+ SCs in the normal and ototoxically damaged cochlea, but also increased Lgr5 expression in the adult mouse cochlea after deafening, suggesting long-term availability of potential target cells for future regenerative therapies.
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Affiliation(s)
- Natalia Smith-Cortinez
- Department of Otorhinolaryngology-Head and Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands
- UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Ferry G. J. Hendriksen
- Department of Otorhinolaryngology-Head and Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands
| | - Dyan Ramekers
- Department of Otorhinolaryngology-Head and Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands
- UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Robert J. Stokroos
- Department of Otorhinolaryngology-Head and Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands
- UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Huib Versnel
- Department of Otorhinolaryngology-Head and Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands
- UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Louise V. Straatman
- Department of Otorhinolaryngology-Head and Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands
- UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
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Wagner EL, Im JS, Sala S, Nakahata MI, Imbery TE, Li S, Chen D, Nimchuk K, Noy Y, Archer DW, Xu W, Hashisaki G, Avraham KB, Oakes PW, Shin JB. Repair of noise-induced damage to stereocilia F-actin cores is facilitated by XIRP2 and its novel mechanosensor domain. eLife 2023; 12:e72681. [PMID: 37294664 PMCID: PMC10259482 DOI: 10.7554/elife.72681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 05/17/2023] [Indexed: 06/11/2023] Open
Abstract
Prolonged exposure to loud noise has been shown to affect inner ear sensory hair cells in a variety of deleterious manners, including damaging the stereocilia core. The damaged sites can be visualized as 'gaps' in phalloidin staining of F-actin, and the enrichment of monomeric actin at these sites, along with an actin nucleator and crosslinker, suggests that localized remodeling occurs to repair the broken filaments. Herein, we show that gaps in mouse auditory hair cells are largely repaired within 1 week of traumatic noise exposure through the incorporation of newly synthesized actin. We provide evidence that Xin actin binding repeat containing 2 (XIRP2) is required for the repair process and facilitates the enrichment of monomeric γ-actin at gaps. Recruitment of XIRP2 to stereocilia gaps and stress fiber strain sites in fibroblasts is force-dependent, mediated by a novel mechanosensor domain located in the C-terminus of XIRP2. Our study describes a novel process by which hair cells can recover from sublethal hair bundle damage and which may contribute to recovery from temporary hearing threshold shifts and the prevention of age-related hearing loss.
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Affiliation(s)
- Elizabeth L Wagner
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
- Department of Biochemistry & Molecular Genetics, University of VirginiaCharlottesvilleUnited States
| | - Jun-Sub Im
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
| | - Stefano Sala
- Department of Cell & Molecular Physiology, Stritch School of Medicine, Loyola University ChicagoChicagoUnited States
| | - Maura I Nakahata
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
| | - Terence E Imbery
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
- Department of Otolaryngology-Head & Neck Surgery, University of VirginiaCharlottesvilleUnited States
| | - Sihan Li
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
- Department of Biochemistry & Molecular Genetics, University of VirginiaCharlottesvilleUnited States
| | - Daniel Chen
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
| | - Katherine Nimchuk
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
| | - Yael Noy
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv UniversityTel AvivIsrael
| | - David W Archer
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
| | - Wenhao Xu
- Genetically Engineered Murine Model (GEMM) Core, University of VirginiaCharlottesvilleUnited States
| | - George Hashisaki
- Department of Otolaryngology-Head & Neck Surgery, University of VirginiaCharlottesvilleUnited States
| | - Karen B Avraham
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv UniversityTel AvivIsrael
| | - Patrick W Oakes
- Department of Cell & Molecular Physiology, Stritch School of Medicine, Loyola University ChicagoChicagoUnited States
| | - Jung-Bum Shin
- Department of Neuroscience, University of VirginiaCharlottesvilleUnited States
- Department of Biochemistry & Molecular Genetics, University of VirginiaCharlottesvilleUnited States
- Department of Otolaryngology-Head & Neck Surgery, University of VirginiaCharlottesvilleUnited States
- Department of Cell Biology, University of VirginiaCharlottesvilleUnited States
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7
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Oral Administration of TrkB Agonist, 7, 8-Dihydroxyflavone Regenerates Hair Cells and Restores Function after Gentamicin-Induced Vestibular Injury in Guinea Pig. Pharmaceutics 2023; 15:pharmaceutics15020493. [PMID: 36839815 PMCID: PMC9966733 DOI: 10.3390/pharmaceutics15020493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/24/2023] [Accepted: 01/30/2023] [Indexed: 02/05/2023] Open
Abstract
The causes of vestibular dysfunction include the loss of hair cells (HCs), synapses beneath the HCs, and nerve fibers. 7, 8-dihydroxyflavone (DHF) mimics the physiological functions of brain-derived neurotrophic factor. We investigated the effects of the orally-administered DHF in the guinea pig crista ampullaris after gentamicin (GM)-induced injury. Twenty animals treated with GM received daily administration of DHF or saline for 14 or 28 days (DHF (+) or DHF (-) group; N = 5, each). At 14 days after GM treatment, almost all of the HCs had disappeared in both groups. At 28 days, the HCs number in DHF (+) and DHF (-) groups was 74% and 49%, respectively, compared to GM-untreated control. In the ampullary nerves, neurofilament 200 positive rate in the DHF (+) group was 91% at 28 days, which was significantly higher than 42% in DHF (-). On day 28, the synaptic connections observed between C-terminal-binding protein 2-positive and postsynaptic density protein-95-positive puncta were restored, and caloric response was significantly improved in DHF (+) group (canal paresis: 57.4% in DHF (+) and 100% in DHF (-)). Taken together, the oral administration of DHF may be a novel therapeutic approach for treating vestibular dysfunction in humans.
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8
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Foster T, Lewkowicz M, Quintas C, Ionescu CM, Jones M, Wagle SR, Kovacevic B, Wong EYM, Mooranian A, Al-Salami H. Novel Nanoencapsulation Technology and its Potential Role in Bile Acid-Based Targeted Gene Delivery to the Inner Ear. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2204986. [PMID: 36538754 DOI: 10.1002/smll.202204986] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 10/05/2022] [Indexed: 06/17/2023]
Abstract
Hearing loss impacts a large proportion of the global population. Damage to the inner ear, in particular the sensitive hair cells, can impact individuals for the rest of their lives. There are very limited options for interventions after damage to these cells has occurred. Targeted gene delivery may provide an effective means to trigger appropriate differentiation of progenitor cells for effective replacement of these sensitive hair cells. There are several hurdles that need to be overcome to effectively deliver these genes. Nanoencapsulation technology has previously been used for the delivery of pharmaceuticals, proteins and nucleic acids, and may provide an effective means of delivering genes to trigger appropriate differentiation. This review investigates the background of hearing loss, current advancements and pitfalls of gene delivery, and how nanoencapsulation may be useful.
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Affiliation(s)
- Thomas Foster
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Perth, Western Australia, Australia
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands 6009, Perth, Western Australia, Australia
| | - Michael Lewkowicz
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Perth, Western Australia, Australia
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands 6009, Perth, Western Australia, Australia
| | - Christina Quintas
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Perth, Western Australia, Australia
| | - Corina Mihaela Ionescu
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Perth, Western Australia, Australia
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands 6009, Perth, Western Australia, Australia
| | - Melissa Jones
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Perth, Western Australia, Australia
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands 6009, Perth, Western Australia, Australia
| | - Susbin Raj Wagle
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Perth, Western Australia, Australia
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands 6009, Perth, Western Australia, Australia
| | - Bozica Kovacevic
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Perth, Western Australia, Australia
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands 6009, Perth, Western Australia, Australia
| | - Elaine Y M Wong
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands 6009, Perth, Western Australia, Australia
| | - Armin Mooranian
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Perth, Western Australia, Australia
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands 6009, Perth, Western Australia, Australia
- School of Pharmacy, University of Otago, Dunedin, Otago, 9016, New Zealand
| | - Hani Al-Salami
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School & Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Perth, Western Australia, Australia
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands 6009, Perth, Western Australia, Australia
- Medical School, University of Western Australia, Perth, Western Australia, Australia
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9
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Fogliano C, Motta CM, Avallone B. Salicylate attenuates gentamicin-induced ototoxicity and facilitates the recovery in the basilar papilla of the lizard Podarcis siculus. Neurotoxicology 2022; 93:301-310. [DOI: 10.1016/j.neuro.2022.10.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 10/24/2022] [Accepted: 10/24/2022] [Indexed: 11/15/2022]
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10
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Tao L, Segil N. CDK2 regulates aminoglycoside-induced hair cell death through modulating c-Jun activity: Inhibiting CDK2 to preserve hearing. Front Mol Neurosci 2022; 15:1013383. [PMID: 36311033 PMCID: PMC9606710 DOI: 10.3389/fnmol.2022.1013383] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Accepted: 09/27/2022] [Indexed: 11/13/2022] Open
Abstract
Sensory hair cell death caused by the ototoxic side effects of many clinically used drugs leads to permanent sensorineural hearing loss in patients. Aminoglycoside antibiotics are widely used and well-known for their ototoxicity, but the molecular mechanisms of aminoglycoside-induced hair cell death are not well understood. This creates challenges in our attempts to alleviate or prevent such adverse side effects. Here, we report a regulatory role of CDK2 in aminoglycoside-induced hair cell death. Utilizing organotypic cultures of cochleae from neonatal mice, we show that blocking CDK2 activity by either pharmaceutical inhibition or by Cdk2 gene knockout protects hair cells against the ototoxicity of gentamicin—one of the most commonly used aminoglycoside antibiotics—by interfering with intrinsic programmed cell death processes. Specifically, we show that CDK2 inhibition delays the collapse of mitochondria and the activation of a caspase cascade. Furthermore, at the molecular level, inhibition of CDK2 activity influences proapoptotic JNK signaling by reducing the protein level of c-Jun and suppressing the gentamicin-induced upregulation of c-Jun target genes Jun and Bim. Our in vivo studies reveal that Cdk2 gene knockout animals are significantly less sensitive to gentamicin ototoxicity compared to wild-type littermates. Altogether, our work ascertains the non-cell cycle role of CDK2 in regulating aminoglycoside-induced hair cell apoptosis and sheds lights on new potential strategies for hearing protection against ototoxicity.
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Affiliation(s)
- Litao Tao
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
- USC Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
- *Correspondence: Litao Tao,
| | - Neil Segil
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
- USC Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
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11
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Febles NK, Bauer MA, Ding B, Zhu X, Gallant ND, Frisina RD. A combinatorial approach to protect sensory tissue against cisplatin-induced ototoxicity. Hear Res 2022; 415:108430. [PMID: 35051751 PMCID: PMC8810742 DOI: 10.1016/j.heares.2022.108430] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 12/22/2021] [Accepted: 01/03/2022] [Indexed: 12/23/2022]
Abstract
Sensorineural Hearing Loss (SNHL) is a highly prevalent disorder involving permanent damage or loss to the inner ear's mechano-sensory hair cells and nerve fibers. Major contributing causes are ototoxic drugs, loud noises, and aging. Drug-induced hearing loss (DIHL), affects over 25% of patients treated with common therapeutics such as aminoglycoside antibiotics, loop diuretics or chemotherapeutics. A commonly used chemotherapeutic agent, cisplatin, is very effective for treating malignant tumors, but results in a majority of patients experiencing irreversible hearing loss and/or tinnitus. Additionally, since there is currently no FDA-approved treatments for SNHL, attenuation of ototoxicity is a major area of investigation in oncology, otolaryngology and hearing research. Several potential otoprotective agents have been investigated at the clinical trial stage, but none have progressed to a full FDA-approval. In this study, we investigated a combinatorial approach comprised of an antioxidant, a p53 inhibitor and a neurotrophin, as a multifactorial otoprotective treatment for cisplatin exposure. In vitro, HEI-OC1 cells, an immortalized organ of Corti epithelial cell line, pre-treated with this biotherapeutic cocktail had significantly reduced cisplatin-induced cell death, DNA fragmentation, and apoptotic activation. In an ex vivo study, rat pup D2-D3 organ of Corti explants, significant protection against cisplatin-based hair cell and neuronal loss was achieved by delivery of the same combinatorial pretreatment. Interestingly, the hair cell protection was localized to the basal and middle regions of the organ of Corti. Together, these findings highlight a novel approach to attenuate cisplatin ototoxicity and potentially prevent DIHL by addressing biological mechanisms of cisplatin ototoxicity.
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Affiliation(s)
- Nicole K. Febles
- Department of Medical Engineering, University of South Florida, Tampa, FL 33620,Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33602
| | - Mark A. Bauer
- Department of Medical Engineering, University of South Florida, Tampa, FL 33620,Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33602
| | - Bo Ding
- Department of Communicative Sciences and Disorders, University of South Florida, Tampa, FL 33602,Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33602
| | - Xiaoxia Zhu
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33602
| | - Nathan D. Gallant
- Department of Mechanical Engineering, University of South Florida, Tampa, FL 33602,Address for all correspondence: Robert Frisina, Ph.D., Department of Medical Engineering, University of South Florida, 4202 E Fowler Avenue, ENG 030, Tampa, FL 33620, Tel: 813-974-4013, , Nathan D. Gallant, Ph.D., Department of Mechanical Engineering, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620, Tel: 813-974-5840,
| | - Robert D. Frisina
- Department of Medical Engineering, University of South Florida, Tampa, FL 33620,Department of Communicative Sciences and Disorders, University of South Florida, Tampa, FL 33602,Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33602,Address for all correspondence: Robert Frisina, Ph.D., Department of Medical Engineering, University of South Florida, 4202 E Fowler Avenue, ENG 030, Tampa, FL 33620, Tel: 813-974-4013, , Nathan D. Gallant, Ph.D., Department of Mechanical Engineering, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620, Tel: 813-974-5840,
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12
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Rai V, Tu S, Frank JR, Zuo J. Molecular Pathways Modulating Sensory Hair Cell Regeneration in Adult Mammalian Cochleae: Progress and Perspectives. Int J Mol Sci 2021; 23:ijms23010066. [PMID: 35008497 PMCID: PMC8745006 DOI: 10.3390/ijms23010066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/20/2021] [Accepted: 12/20/2021] [Indexed: 12/30/2022] Open
Abstract
Noise-induced, drug-related, and age-related disabling hearing loss is a major public health problem and affect approximately 466 million people worldwide. In non-mammalian vertebrates, the death of sensory hair cells (HCs) induces the proliferation and transdifferentiation of adjacent supporting cells into new HCs; however, this capacity is lost in juvenile and adult mammalian cochleae leading to permanent hearing loss. At present, cochlear implants and hearing devices are the only available treatments and can help patients to a certain extent; however, no biological approach or FDA-approved drug is effective to treat disabling hearing loss and restore hearing. Recently, regeneration of mammalian cochlear HCs by modulating molecular pathways or transcription factors has offered some promising results, although the immaturity of the regenerated HCs remains the biggest concern. Furthermore, most of the research done is in neonates and not in adults. This review focuses on critically summarizing the studies done in adult mammalian cochleae and discusses various strategies to elucidate novel transcription factors for better therapeutics.
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Affiliation(s)
| | | | | | - Jian Zuo
- Correspondence: ; Tel.: +1-(402)-280-2916
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13
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Smith-Cortinez N, Yadak R, Hendriksen FGJ, Sanders E, Ramekers D, Stokroos RJ, Versnel H, Straatman LV. LGR5-Positive Supporting Cells Survive Ototoxic Trauma in the Adult Mouse Cochlea. Front Mol Neurosci 2021; 14:729625. [PMID: 34675775 PMCID: PMC8523910 DOI: 10.3389/fnmol.2021.729625] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 09/07/2021] [Indexed: 11/13/2022] Open
Abstract
Sensorineural hearing loss is mainly caused by irreversible damage to sensory hair cells (HCs). A subgroup of supporting cells (SCs) in the cochlea express leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5), a marker for tissue-resident stem cells. LGR5+ SCs could be used as an endogenous source of stem cells for regeneration of HCs to treat hearing loss. Here, we report long-term presence of LGR5+ SCs in the mature adult cochlea and survival of LGR5+ SCs after severe ototoxic trauma characterized by partial loss of inner HCs and complete loss of outer HCs. Surviving LGR5+ SCs (confirmed by GFP expression) were located in the third row of Deiters' cells. We observed a change in the intracellular localization of GFP, from the nucleus in normal-hearing to cytoplasm and membrane in deafened mice. These data suggests that the adult mammalian cochlea possesses properties essential for regeneration even after severe ototoxic trauma.
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Affiliation(s)
- Natalia Smith-Cortinez
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands.,UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Rana Yadak
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands.,UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Ferry G J Hendriksen
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands
| | - Eefje Sanders
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands
| | - Dyan Ramekers
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands.,UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Robert J Stokroos
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands.,UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Huib Versnel
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands.,UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Louise V Straatman
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands.,UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
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14
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Montalbano G, Olivotto I, Germanà A, Randazzo B. Evaluation of the hair cell regeneration and claudin b and phoenix gene expression during exposure to low concentrations of cadmium and zinc in early developing zebrafish larvae. Comp Biochem Physiol C Toxicol Pharmacol 2021; 248:109116. [PMID: 34182097 DOI: 10.1016/j.cbpc.2021.109116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 06/14/2021] [Accepted: 06/18/2021] [Indexed: 12/28/2022]
Abstract
Zebrafish possess hair cells on the body surface similar to that of mammals inner hear, in particular in the neuromasts, and due to its ability in regenerating damaged hair cells, is regularly used as a powerful animal model to study in vivo cytotoxicity. Among the factors leading to hair cell disruption, metal ions are of particular concern since they are important environmental pollutants. To date, several studies on zebrafish hair cell regeneration after metal exposure exist, while no data on regeneration during continuous metal exposure are available. In the present study, neuromast hair cell disruption and regeneration were assessed in zebrafish larvae for the first time during zinc (Zn) and cadmium (Cd) continuous exposure and a visual and molecular approach was adopted. Fluorescent vital dye DASPEI was used to assess hair cell regeneration and the gene expression of claudin b (cldnb) and phoenix (pho), was analyzed. Metallotionein-2 (mt2) gene expression was used as standard molecular marker of metal toxicity and confirmed the higher toxicity of Cd compared to Zn. In addition, Cd caused a delay in hair cell regeneration compared to Zn. Molecular analysis showed cldnb gene expression increased in relation to the metal concentrations used, confirming the involvement of this gene in hair cell regeneration. On the contrary, a dramatic decrease of pho gene expression was observed in Cd exposed groups, suggesting a negative impact of Cd on pho expression, thus negatively interfering with hair cell regeneration in zebrafish larvae exposed to this metal.
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Affiliation(s)
| | - Ike Olivotto
- Polytechnic University of Marche, Department of Life and Environmental Sciences, Ancona, Italy
| | - Antonino Germanà
- Messina Study University, Department of Veterinary Sciences, Messina, Italy
| | - Basilio Randazzo
- Polytechnic University of Marche, Department of Life and Environmental Sciences, Ancona, Italy.
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15
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González-Garrido A, Pujol R, López-Ramírez O, Finkbeiner C, Eatock RA, Stone JS. The Differentiation Status of Hair Cells That Regenerate Naturally in the Vestibular Inner Ear of the Adult Mouse. J Neurosci 2021; 41:7779-7796. [PMID: 34301830 PMCID: PMC8445055 DOI: 10.1523/jneurosci.3127-20.2021] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 07/07/2021] [Accepted: 07/19/2021] [Indexed: 11/21/2022] Open
Abstract
Aging, disease, and trauma can lead to loss of vestibular hair cells and permanent vestibular dysfunction. Previous work showed that, following acute destruction of ∼95% of vestibular hair cells in adult mice, ∼20% regenerate naturally (without exogenous factors) through supporting cell transdifferentiation. There is, however, no evidence for the recovery of vestibular function. To gain insight into the lack of functional recovery, we assessed functional differentiation in regenerated hair cells for up to 15 months, focusing on key stages in stimulus transduction and transmission: hair bundles, voltage-gated conductances, and synaptic contacts. Regenerated hair cells had many features of mature type II vestibular hair cells, including polarized mechanosensitive hair bundles with zone-appropriate stereocilia heights, large voltage-gated potassium currents, basolateral processes, and afferent and efferent synapses. Regeneration failed, however, to recapture the full range of properties of normal populations, and many regenerated hair cells had some properties of immature hair cells, including small transduction currents, voltage-gated sodium currents, and small or absent HCN (hyperpolarization-activated cyclic nucleotide-gated) currents. Furthermore, although mouse vestibular epithelia normally have slightly more type I hair cells than type II hair cells, regenerated hair cells acquired neither the low-voltage-activated potassium channels nor the afferent synaptic calyces that distinguish mature type I hair cells from type II hair cells and confer distinctive physiology. Thus, natural regeneration of vestibular hair cells in adult mice is limited in total cell number, cell type diversity, and extent of cellular differentiation, suggesting that manipulations are needed to promote full regeneration with the potential for recovery of vestibular function.SIGNIFICANCE STATEMENT Death of inner ear hair cells in adult mammals causes permanent loss of hearing and balance. In adult mice, the sudden death of most vestibular hair cells stimulates the production of new hair cells but does not restore balance. We investigated whether the lack of systems-level function reflects functional deficiencies in the regenerated hair cells. The regenerated population acquired mechanosensitivity, voltage-gated channels, and afferent synapses, but did not reproduce the full range of hair cell types. Notably, no regenerated cells acquired the distinctive properties of type I hair cells, a major functional class in amniote vestibular organs. To recover vestibular system function in adults, we may need to solve how to regenerate the normal variety of mature hair cells.
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Affiliation(s)
| | - Rémy Pujol
- The Virginia Merrill Bloedel Hearing Research Center and the Department of Otolaryngology Head and Neck Surgery, University of Washington, Seattle, Washington 98195
- Institute for Neurosciences of Montpellier-Institut National de la Santé et de la Recherche Médicale Unit 1052, University of Montpellier, 34091 Montpellier, France
| | - Omar López-Ramírez
- Department of Neurobiology, University of Chicago, Chicago, Illinois 60637
| | - Connor Finkbeiner
- The Virginia Merrill Bloedel Hearing Research Center and the Department of Otolaryngology Head and Neck Surgery, University of Washington, Seattle, Washington 98195
| | - Ruth Anne Eatock
- Department of Neurobiology, University of Chicago, Chicago, Illinois 60637
| | - Jennifer S Stone
- The Virginia Merrill Bloedel Hearing Research Center and the Department of Otolaryngology Head and Neck Surgery, University of Washington, Seattle, Washington 98195
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16
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Tasdemir-Yilmaz OE, Druckenbrod NR, Olukoya OO, Dong W, Yung AR, Bastille I, Pazyra-Murphy MF, Sitko AA, Hale EB, Vigneau S, Gimelbrant AA, Kharchenko PV, Goodrich LV, Segal RA. Diversity of developing peripheral glia revealed by single-cell RNA sequencing. Dev Cell 2021; 56:2516-2535.e8. [PMID: 34469751 DOI: 10.1016/j.devcel.2021.08.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 05/31/2021] [Accepted: 08/06/2021] [Indexed: 12/22/2022]
Abstract
The peripheral nervous system responds to a wide variety of sensory stimuli, a process that requires great neuronal diversity. These diverse neurons are closely associated with glial cells originating from the neural crest. However, the molecular nature and diversity among peripheral glia are not understood. Here, we used single-cell RNA sequencing to profile developing and mature glia from somatosensory dorsal root ganglia and auditory spiral ganglia. We found that glial precursors (GPs) in these two systems differ in their transcriptional profiles. Despite their unique features, somatosensory and auditory GPs undergo convergent differentiation to generate molecularly uniform myelinating and non-myelinating Schwann cells. By contrast, somatosensory and auditory satellite glial cells retain system-specific features. Lastly, we identified a glial signature gene set, providing new insights into commonalities among glia across the nervous system. This survey of gene expression in peripheral glia constitutes a resource for understanding functions of glia across different sensory modalities.
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Affiliation(s)
- Ozge E Tasdemir-Yilmaz
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Noah R Druckenbrod
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | | | - Weixiu Dong
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA 02115, USA
| | - Andrea R Yung
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Isle Bastille
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Maria F Pazyra-Murphy
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Austen A Sitko
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Evan B Hale
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Sébastien Vigneau
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | | | - Peter V Kharchenko
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA 02115, USA
| | - Lisa V Goodrich
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
| | - Rosalind A Segal
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
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17
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Impact of Processing Conditions on Rheology, Tribology and Wet Lubrication Performance of a Novel Amino Lipid Hair Conditioner. COSMETICS 2021. [DOI: 10.3390/cosmetics8030077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The objective of this work was to carry out a comprehensive evaluation of the performance of a novel cationic amino lipid surfactant, Brassicyl Valinate Esylate (BVE), in contrast to conventional alkyl quaternary ammonium surfactants (quats), through a study of the effects of process mixing speed on its overall rheological, tribological and wet lubrication performance in comparison to BTAC and CTAC, two cationic surfactants widely used in cosmetics. The major cosmetic application of cationic surfactants is in the preparation of hair conditioners. Hence, this analysis was done firstly by conducting tensile combing tests to evaluate reduction in wet lubrication which translates to conditioning performance. The combing results serve as a testing metric that adequately corresponds to consumer perception of conditioned hair. To correlate this technically, yield stress measurements were conducted to establish rheologic profiles of the conditioner formulations, and in vitro tribological testing of the emulsion systems between two steel surfaces were done to technically simulate the spreading and rubbing of conditioner on the hair. The effect of processing conditions on the formulations was then evaluated. BVE was found to be an effective conditioning surfactant suitable as an eco-friendly replacement for BTAC and CTAC in hair conditioner formulations. The results showed that higher shear mixing rates during formulation lead to poorer performance effects evident through decreased yield stress values, lower percentage reduction in combing force and a higher coefficient of friction.
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18
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Enhancer decommissioning imposes an epigenetic barrier to sensory hair cell regeneration. Dev Cell 2021; 56:2471-2485.e5. [PMID: 34331868 DOI: 10.1016/j.devcel.2021.07.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 06/24/2021] [Accepted: 07/08/2021] [Indexed: 01/02/2023]
Abstract
Adult mammalian tissues such as heart, brain, retina, and the sensory structures of the inner ear do not effectively regenerate, although a latent capacity for regeneration exists at embryonic and perinatal times. We explored the epigenetic basis for this latent regenerative potential in the mouse inner ear and its rapid loss during maturation. In perinatal supporting cells, whose fate is maintained by Notch-mediated lateral inhibition, the hair cell enhancer network is epigenetically primed (H3K4me1) but silenced (active H3K27 de-acetylation and trimethylation). Blocking Notch signaling during the perinatal period of plasticity rapidly eliminates epigenetic silencing and allows supporting cells to transdifferentiate into hair cells. Importantly, H3K4me1 priming of the hair cell enhancers in supporting cells is removed during the first post-natal week, coinciding with the loss of transdifferentiation potential. We hypothesize that enhancer decommissioning during cochlear maturation contributes to the failure of hair cell regeneration in the mature organ of Corti.
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19
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Maharajan N, Cho GW, Jang CH. Therapeutic Application of Mesenchymal Stem Cells for Cochlear Regeneration. In Vivo 2021; 35:13-22. [PMID: 33402445 DOI: 10.21873/invivo.12227] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 09/27/2020] [Accepted: 09/30/2020] [Indexed: 12/11/2022]
Abstract
Hearing loss is one of the major worldwide health problems that seriously affects human social and cognitive development. In the auditory system, three components outer ear, middle ear and inner ear are essential for the hearing mechanism. In the inner ear, sensory hair cells and ganglion neuronal cells are the essential supporters for hearing mechanism. Damage to these cells can be caused by long-term exposure of excessive noise, ototoxic drugs (aminoglycosides), ear tumors, infections, heredity and aging. Since mammalian cochlear hair cells do not regenerate naturally, some therapeutic interventions may be required to replace the damaged or lost cells. Cochlear implants and hearing aids are the temporary solutions for people suffering from severe hearing loss. The current discoveries in gene therapy may provide a deeper understanding in essential genes for the inner ear regeneration. Stem cell migration, survival and differentiation to supporting cells, cochlear hair cells and spiral ganglion neurons are the important foundation in understanding stem cell therapy. Moreover, mesenchymal stem cells (MSCs) from different sources (bone marrow, umbilical cord, adipose tissue and placenta) could be used in inner ear therapy. Transplanted MSCs in the inner ear can recruit homing factors at the damaged sites to induce transdifferentiation into inner hair cells and ganglion neurons or regeneration of sensory hair cells, thus enhancing the cochlear function. This review summarizes the potential application of mesenchymal stem cells in hearing restoration and combining stem cell and molecular therapeutic strategies can also be used in the recovery of cochlear function.
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Affiliation(s)
- Nagarajan Maharajan
- Department of Biology, College of Natural Science, BK21-Plus Research Team for Bioactive Control Technology, Chosun University, Gwangju, Republic of Korea
| | - Gwang Won Cho
- Department of Biology, College of Natural Science, BK21-Plus Research Team for Bioactive Control Technology, Chosun University, Gwangju, Republic of Korea
| | - Chul Ho Jang
- Department of Otolaryngology, Chonnam National University Medical School, Gwangju, Republic of Korea
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20
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Kastan N, Gnedeva K, Alisch T, Petelski AA, Huggins DJ, Chiaravalli J, Aharanov A, Shakked A, Tzahor E, Nagiel A, Segil N, Hudspeth AJ. Small-molecule inhibition of Lats kinases may promote Yap-dependent proliferation in postmitotic mammalian tissues. Nat Commun 2021; 12:3100. [PMID: 34035288 PMCID: PMC8149661 DOI: 10.1038/s41467-021-23395-3] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 04/20/2021] [Indexed: 02/04/2023] Open
Abstract
Hippo signaling is an evolutionarily conserved pathway that restricts growth and regeneration predominantly by suppressing the activity of the transcriptional coactivator Yap. Using a high-throughput phenotypic screen, we identified a potent and non-toxic activator of Yap. In vitro kinase assays show that the compound acts as an ATP-competitive inhibitor of Lats kinases-the core enzymes in Hippo signaling. The substance prevents Yap phosphorylation and induces proliferation of supporting cells in the murine inner ear, murine cardiomyocytes, and human Müller glia in retinal organoids. RNA sequencing indicates that the inhibitor reversibly activates the expression of transcriptional Yap targets: upon withdrawal, a subset of supporting-cell progeny exits the cell cycle and upregulates genes characteristic of sensory hair cells. Our results suggest that the pharmacological inhibition of Lats kinases may promote initial stages of the proliferative regeneration of hair cells, a process thought to be permanently suppressed in the adult mammalian inner ear.
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MESH Headings
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Animals
- Cell Line
- Cell Line, Tumor
- Cell Proliferation/drug effects
- Cell Proliferation/genetics
- Ependymoglial Cells/cytology
- Ependymoglial Cells/drug effects
- Ependymoglial Cells/metabolism
- HEK293 Cells
- Hair Cells, Auditory, Inner/cytology
- Hair Cells, Auditory, Inner/drug effects
- Hair Cells, Auditory, Inner/metabolism
- Humans
- Mice, Knockout
- Mice, Transgenic
- Myocytes, Cardiac/cytology
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/metabolism
- Protein Serine-Threonine Kinases/antagonists & inhibitors
- Protein Serine-Threonine Kinases/metabolism
- Signal Transduction/drug effects
- Signal Transduction/genetics
- Small Molecule Libraries/pharmacology
- Tumor Suppressor Proteins/antagonists & inhibitors
- Tumor Suppressor Proteins/metabolism
- YAP-Signaling Proteins
- Mice
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Affiliation(s)
- Nathaniel Kastan
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
- Laboratory of Sensory Neuroscience, The Rockefeller University, New York, NY, USA
| | - Ksenia Gnedeva
- Tina and Rick Caruso Department of Otolaryngology-Head and Neck Surgery, University of Southern California, Los Angles, CA, USA.
| | - Theresa Alisch
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
- Laboratory of Sensory Neuroscience, The Rockefeller University, New York, NY, USA
| | - Aleksandra A Petelski
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
- Laboratory of Sensory Neuroscience, The Rockefeller University, New York, NY, USA
- Department of Bioengineering and Barnett Institute, Northeastern University, Boston, MA, USA
| | - David J Huggins
- Tri-Institutional Therapeutics Discovery Institute, New York, NY, USA
- Department of Physiology and Biophysics, Weill Cornell Medical College of Cornell University, New York, NY, USA
| | - Jeanne Chiaravalli
- High-Throughput Screening Resource Center, The Rockefeller University, New York, NY, USA
- Institut Pasteur, Paris, France
| | - Alla Aharanov
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Avraham Shakked
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Eldad Tzahor
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Aaron Nagiel
- Department of Surgery Children's Hospital Los Angeles, Vision Center, Los Angeles, CA, USA
- Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, CA, USA
- USC Roski Eye Institute, Department of Ophthalmology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Neil Segil
- Tina and Rick Caruso Department of Otolaryngology-Head and Neck Surgery, University of Southern California, Los Angles, CA, USA
- Eli and Edythe Broad CIRM Center for Regenerative Medicine and Stem Cell Research, University of Southern California, Los Angles, CA, USA
| | - A J Hudspeth
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
- Laboratory of Sensory Neuroscience, The Rockefeller University, New York, NY, USA
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21
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Sound-level Monitoring Earphones With Smartphone Feedback as an Intervention to Promote Healthy Listening Behaviors in Young Adults. Ear Hear 2021; 42:1173-1182. [PMID: 33974781 DOI: 10.1097/aud.0000000000001029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES More than a billion adolescents and youngsters are estimated to be at risk of acquiring recreational noise-induced hearing loss (RNIHL) due to the unsafe use of personal audio systems. RNIHL is preventable; therefore, the present study aimed to determine (i) the accuracy and reliability of dbTrack (Westone) sound-level monitoring earphones and (ii) the effect of sound-level monitoring earphones with smartphone feedback and hearing-health information as an intervention to promote healthy listening behaviors in young adults. DESIGN The study consisted of two phases: the first phase investigated the accuracy and reliability of dbTrack sound-level monitoring earphones. Accuracy was determined by comparing earphone measurements to sound level meter measurements. Intradevice reliability was determined by comparing earphone measurements during test-retest conditions. Nineteen participants were recruited through convenience sampling to determine within-subject reliability by comparing in-ear sound levels measured by the earphones during test-retest conditions. For the second phase of the study, a single-group pretest-posttest design was utilized. Forty participants, recruited through snowball sampling, utilized the sound-level monitoring earphones with the accompanying dbTrack smartphone application for 4 weeks. The application's smartphone feedback was disabled during the first 2 weeks (pretest condition) and enabled during the last 2 weeks (posttest condition). Average daily intensities, durations, and sound dosages measured during pre- and posttest conditions were compared. RESULTS Phase 1 dbTrack earphone measurements were within 1 dB when compared with sound level meter measurements. Earphones were also within 1 dB in repeated measures across earphones and across participants. Phase 2 posttest average daily intensity decreased by 8.7 dB (18.3 SD), duration decreased by 7.6 minutes (46.6 SD), and sound dose decreased by 4128.4% (24965.5% SD). Differences in intensity and sound dose were significantly lower with a small and medium effect size, respectively. CONCLUSIONS This study's preliminary data indicate that dbTrack (Westone) sound-level monitoring earphones with a calibrated in-ear microphone can reliably and accurately measure personal audio systems sound exposure. Preliminary results also suggest that feedback on sound exposure using the accurate sound-level monitoring earphones with the accompanying dbTrack application can potentially promote safe listening behavior in young adults and reduce the risk of acquiring an RNIHL.
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22
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Mittal R, Bencie N, Liu G, Eshraghi N, Nisenbaum E, Blanton SH, Yan D, Mittal J, Dinh CT, Young JI, Gong F, Liu XZ. Recent advancements in understanding the role of epigenetics in the auditory system. Gene 2020; 761:144996. [PMID: 32738421 DOI: 10.1016/j.gene.2020.144996] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 07/21/2020] [Indexed: 11/19/2022]
Abstract
Sensorineural deafness in mammals is most commonly caused by damage to inner ear sensory epithelia, or hair cells, and can be attributed to genetic and environmental causes. After undergoing trauma, many non-mammalian organisms, including reptiles, birds, and zebrafish, are capable of regenerating damaged hair cells. Mammals, however, are not capable of regenerating damaged inner ear sensory epithelia, so that hair cell damage is permanent and can lead to hearing loss. The field of epigenetics, which is the study of various phenotypic changes caused by modification of genetic expression rather than alteration of DNA sequence, has seen numerous developments in uncovering biological mechanisms of gene expression and creating various medical treatments. However, there is a lack of information on the precise contribution of epigenetic modifications in the auditory system, specifically regarding their correlation with development of inner ear (cochlea) and consequent hearing impairment. Current studies have suggested that epigenetic modifications influence differentiation, development, and protection of auditory hair cells in cochlea, and can lead to hair cell degeneration. The objective of this article is to review the existing literature and discuss the advancements made in understanding epigenetic modifications of inner ear sensory epithelial cells. The analysis of the emerging epigenetic mechanisms related to inner ear sensory epithelial cells development, differentiation, protection, and regeneration will pave the way to develop novel therapeutic strategies for hearing loss.
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Affiliation(s)
- Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Nicole Bencie
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - George Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Nicolas Eshraghi
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Eric Nisenbaum
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Susan H Blanton
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA; Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jeenu Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Christine T Dinh
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Juan I Young
- Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Feng Gong
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Xue Zhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA; Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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23
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Recent advancements in understanding the role of epigenetics in the auditory system. Gene 2020. [DOI: 10.1016/j.gene.2020.144996
expr 848609818 + 898508594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
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24
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Fanaei H, Pourbakht A, Jafarzadeh S. Bilateral Carotid Artery Occlusion and Cochlear Oxidative Stress and Hearing Loss in Rats. Basic Clin Neurosci 2020; 11:821-829. [PMID: 33850619 PMCID: PMC8019843 DOI: 10.32598/bcn.11.6.1154.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/10/2018] [Accepted: 05/06/2019] [Indexed: 11/20/2022] Open
Abstract
Introduction: This study aimed to evaluate the effects of bilateral carotid artery occlusion on cochlear oxidative stress and hearing status in rats. Methods: The rats were divided into two sets. The first set was used for electrophysiological recording (click and 4 kHz tone burst auditory brainstem responses and electrocochleography) on the day before surgery and then on the first, fourth, and seventh days after surgery. Animals of the second set were used for biochemical analysis. The cochlea of animals in the second set was collected on the first, fourth, and seventh days after carotids occlusion for biochemical analysis. For the control groups, no carotids occlusion was done. For ischemia induction, both common carotid arteries were occluded for 20 minutes. Results: Electrophysiological analysis showed that burst auditory brainstem thresholds significantly elevated after common carotid arteries occlusion on the first, fourth, and seventh days after surgery with abnormal electrocochleography results at 75%, 70%, and 85% on the first, fourth, and seventh days after surgery, respectively. The electrophysiological finding confirmed by biochemical results that showed malondialdehyde and nitric oxide levels increased and superoxide dismutase and catalase activities decreased after occlusion in cochlea tissue. Conclusion: This study showed that bilateral common carotid artery occlusion increases cochlear oxidative stress and induces hearing loss in rats.
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Affiliation(s)
- Hamed Fanaei
- Department of Clinical Physiology, Faculty of Medical Sciences, Zahedan University of Medical Sciences, Zahedan, Iran
| | - Akram Pourbakht
- Department of Audiology, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran
| | - Sadegh Jafarzadeh
- Department of Audiology, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
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25
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Zhang Y, Zhang S, Zhang Z, Dong Y, Ma X, Qiang R, Chen Y, Gao X, Zhao C, Chen F, He S, Chai R. Knockdown of Foxg1 in Sox9+ supporting cells increases the trans-differentiation of supporting cells into hair cells in the neonatal mouse utricle. Aging (Albany NY) 2020; 12:19834-19851. [PMID: 33099273 PMCID: PMC7655167 DOI: 10.18632/aging.104009] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 08/15/2020] [Indexed: 05/30/2023]
Abstract
Foxg1 plays important roles in regeneration of hair cell (HC) in the cochlea of neonatal mouse. Here, we used Sox9-CreER to knock down Foxg1 in supporting cells (SCs) in the utricle in order to investigate the role of Foxg1 in HC regeneration in the utricle. We found Sox9 an ideal marker of utricle SCs and bred Sox9CreER/+Foxg1loxp/loxp mice to conditionally knock down Foxg1 in utricular SCs. Conditional knockdown (cKD) of Foxg1 in SCs at postnatal day one (P01) led to increased number of HCs at P08. These regenerated HCs had normal characteristics, and could survive to at least P30. Lineage tracing showed that a significant portion of newly regenerated HCs originated from SCs in Foxg1 cKD mice compared to the mice subjected to the same treatment, which suggested SCs trans-differentiate into HCs in the Foxg1 cKD mouse utricle. After neomycin treatment in vitro, more HCs were observed in Foxg1 cKD mice utricle compared to the control group. Together, these results suggest that Foxg1 cKD in utricular SCs may promote HC regeneration by inducing trans-differentiation of SCs. This research therefore provides theoretical basis for the effects of Foxg1 in trans-differentiation of SCs and regeneration of HCs in the mouse utricle.
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Affiliation(s)
- Yuan Zhang
- MOE Key Laboratory for Developmental Genes and Human Disease, School of Life Sciences and Technology, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Shasha Zhang
- MOE Key Laboratory for Developmental Genes and Human Disease, School of Life Sciences and Technology, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Zhonghong Zhang
- Department of Ophthalmology, Zhongda Hospital, Southeast University, Nanjing, China
| | - Ying Dong
- MOE Key Laboratory for Developmental Genes and Human Disease, School of Life Sciences and Technology, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Xiangyu Ma
- MOE Key Laboratory for Developmental Genes and Human Disease, School of Life Sciences and Technology, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Ruiying Qiang
- MOE Key Laboratory for Developmental Genes and Human Disease, School of Life Sciences and Technology, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Yin Chen
- Department of Otolaryngology Head and Neck Surgery, Affiliated Drum Tower Hospital of Nanjing University Medical School, Jiangsu Provincial Key Medical Discipline (Laboratory), Nanjing, China
| | - Xia Gao
- Department of Otolaryngology Head and Neck Surgery, Affiliated Drum Tower Hospital of Nanjing University Medical School, Jiangsu Provincial Key Medical Discipline (Laboratory), Nanjing, China
| | - Chunjie Zhao
- MOE Key Laboratory for Developmental Genes and Human Disease, School of Life Sciences and Technology, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Fangyi Chen
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, China
| | - Shuangba He
- Department of Otolaryngology Head and Neck, Nanjing Tongren Hospital, School of Medicine, Southeast University, China
| | - Renjie Chai
- MOE Key Laboratory for Developmental Genes and Human Disease, School of Life Sciences and Technology, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
- Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Science, Beijing, China
- Beijing Key Laboratory of Neural Regeneration and Repair, Capital Medical University, Beijing, China
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26
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Gu S, Olszewski R, Taukulis I, Wei Z, Martin D, Morell RJ, Hoa M. Characterization of rare spindle and root cell transcriptional profiles in the stria vascularis of the adult mouse cochlea. Sci Rep 2020; 10:18100. [PMID: 33093630 PMCID: PMC7581811 DOI: 10.1038/s41598-020-75238-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 10/12/2020] [Indexed: 12/20/2022] Open
Abstract
The stria vascularis (SV) in the cochlea generates and maintains the endocochlear potential, thereby playing a pivotal role in normal hearing. Knowing transcriptional profiles and gene regulatory networks of SV cell types establishes a basis for studying the mechanism underlying SV-related hearing loss. While we have previously characterized the expression profiles of major SV cell types in the adult mouse, transcriptional profiles of rare SV cell types remained elusive due to the limitation of cell capture in single-cell RNA-Seq. The role of these rare cell types in the homeostatic function of the adult SV remain largely undefined. In this study, we performed single-nucleus RNA-Seq on the adult mouse SV in conjunction with sample preservation treatments during the isolation steps. We distinguish rare SV cell types, including spindle cells and root cells, from other cell types, and characterize their transcriptional profiles. Furthermore, we also identify and validate novel specific markers for these rare SV cell types. Finally, we identify homeostatic gene regulatory networks within spindle and root cells, establishing a basis for understanding the functional roles of these cells in hearing. These novel findings will provide new insights for future work in SV-related hearing loss and hearing fluctuation.
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Affiliation(s)
- Shoujun Gu
- Auditory Development and Restoration Program, National Institutes on Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, 35 Convent Dr., Room 1F-226, Bethesda, MD, 20892, USA
| | - Rafal Olszewski
- Auditory Development and Restoration Program, National Institutes on Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, 35 Convent Dr., Room 1F-226, Bethesda, MD, 20892, USA
| | - Ian Taukulis
- Auditory Development and Restoration Program, National Institutes on Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, 35 Convent Dr., Room 1F-226, Bethesda, MD, 20892, USA
| | - Zheng Wei
- Biomedical Research Informatics Office, National Institute of Dental and Craniofacial Research, NIH, Bethesda, MD, 20892, USA
| | - Daniel Martin
- Biomedical Research Informatics Office, National Institute of Dental and Craniofacial Research, NIH, Bethesda, MD, 20892, USA
| | - Robert J Morell
- Computational Biology and Genomics Core, National Institutes on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Michael Hoa
- Auditory Development and Restoration Program, National Institutes on Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, 35 Convent Dr., Room 1F-226, Bethesda, MD, 20892, USA.
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27
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Menendez L, Trecek T, Gopalakrishnan S, Tao L, Markowitz AL, Yu HV, Wang X, Llamas J, Huang C, Lee J, Kalluri R, Ichida J, Segil N. Generation of inner ear hair cells by direct lineage conversion of primary somatic cells. eLife 2020; 9:e55249. [PMID: 32602462 PMCID: PMC7326493 DOI: 10.7554/elife.55249] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 05/27/2020] [Indexed: 02/06/2023] Open
Abstract
The mechanoreceptive sensory hair cells in the inner ear are selectively vulnerable to numerous genetic and environmental insults. In mammals, hair cells lack regenerative capacity, and their death leads to permanent hearing loss and vestibular dysfunction. Their paucity and inaccessibility has limited the search for otoprotective and regenerative strategies. Growing hair cells in vitro would provide a route to overcome this experimental bottleneck. We report a combination of four transcription factors (Six1, Atoh1, Pou4f3, and Gfi1) that can convert mouse embryonic fibroblasts, adult tail-tip fibroblasts and postnatal supporting cells into induced hair cell-like cells (iHCs). iHCs exhibit hair cell-like morphology, transcriptomic and epigenetic profiles, electrophysiological properties, mechanosensory channel expression, and vulnerability to ototoxin in a high-content phenotypic screening system. Thus, direct reprogramming provides a platform to identify causes and treatments for hair cell loss, and may help identify future gene therapy approaches for restoring hearing.
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Affiliation(s)
- Louise Menendez
- Department of Stem Cell and Regenerative Medicine, University of Southern CaliforniaLos AngelesUnited States
- Eli and Edythe Broad Center, University of Southern CaliforniaLos AngelesUnited States
- Zilkha Neurogenetic Institute, University of Southern CaliforniaLos AngelesUnited States
| | - Talon Trecek
- Department of Stem Cell and Regenerative Medicine, University of Southern CaliforniaLos AngelesUnited States
- Eli and Edythe Broad Center, University of Southern CaliforniaLos AngelesUnited States
| | - Suhasni Gopalakrishnan
- Department of Stem Cell and Regenerative Medicine, University of Southern CaliforniaLos AngelesUnited States
- Eli and Edythe Broad Center, University of Southern CaliforniaLos AngelesUnited States
- Zilkha Neurogenetic Institute, University of Southern CaliforniaLos AngelesUnited States
| | - Litao Tao
- Department of Stem Cell and Regenerative Medicine, University of Southern CaliforniaLos AngelesUnited States
- Eli and Edythe Broad Center, University of Southern CaliforniaLos AngelesUnited States
| | - Alexander L Markowitz
- Zilkha Neurogenetic Institute, University of Southern CaliforniaLos AngelesUnited States
- USC Caruso Department of Otolaryngology – Head and Neck Surgery, University of Southern CaliforniaLos AngelesUnited States
| | - Haoze V Yu
- Department of Stem Cell and Regenerative Medicine, University of Southern CaliforniaLos AngelesUnited States
- Eli and Edythe Broad Center, University of Southern CaliforniaLos AngelesUnited States
| | - Xizi Wang
- Department of Stem Cell and Regenerative Medicine, University of Southern CaliforniaLos AngelesUnited States
- Eli and Edythe Broad Center, University of Southern CaliforniaLos AngelesUnited States
| | - Juan Llamas
- Department of Stem Cell and Regenerative Medicine, University of Southern CaliforniaLos AngelesUnited States
- Eli and Edythe Broad Center, University of Southern CaliforniaLos AngelesUnited States
| | | | - James Lee
- DRVision TechnologiesBellevueUnited States
| | - Radha Kalluri
- Zilkha Neurogenetic Institute, University of Southern CaliforniaLos AngelesUnited States
- USC Caruso Department of Otolaryngology – Head and Neck Surgery, University of Southern CaliforniaLos AngelesUnited States
| | - Justin Ichida
- Department of Stem Cell and Regenerative Medicine, University of Southern CaliforniaLos AngelesUnited States
- Eli and Edythe Broad Center, University of Southern CaliforniaLos AngelesUnited States
- Zilkha Neurogenetic Institute, University of Southern CaliforniaLos AngelesUnited States
| | - Neil Segil
- Department of Stem Cell and Regenerative Medicine, University of Southern CaliforniaLos AngelesUnited States
- Eli and Edythe Broad Center, University of Southern CaliforniaLos AngelesUnited States
- USC Caruso Department of Otolaryngology – Head and Neck Surgery, University of Southern CaliforniaLos AngelesUnited States
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28
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Wan L, Lovett M, Warchol ME, Stone JS. Vascular endothelial growth factor is required for regeneration of auditory hair cells in the avian inner ear. Hear Res 2020; 385:107839. [PMID: 31760261 DOI: 10.1016/j.heares.2019.107839] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 10/30/2019] [Accepted: 11/01/2019] [Indexed: 12/12/2022]
Abstract
Hair cells in the auditory organ of the vertebrate inner ear are the sensory receptors that convert acoustic stimuli into electrical signals that are conveyed along the auditory nerve to the brainstem. Hair cells are highly susceptible to ototoxic drugs, infection, and acoustic trauma, which can cause cellular degeneration. In mammals, hair cells that are lost after damage are not replaced, leading to permanent hearing impairments. By contrast, supporting cells in birds and other non-mammalian vertebrates regenerate hair cells after damage, which restores hearing function. The cellular mechanisms that regulate hair cell regeneration are not well understood. We investigated the role of vascular endothelial growth factor (VEGF) during regeneration of auditory hair cells in chickens after ototoxic injury. Using RNA-Seq, immunolabeling, and in situ hybridization, we found that VEGFA, VEGFC, VEGFR1, VEGFR2, and VEGFR3 were expressed in the auditory epithelium, with VEGFA expressed in hair cells and VEGFR1 and VEGFR2 expressed in supporting cells. Using organotypic cultures of the chicken cochlear duct, we found that blocking VEGF receptor activity during hair cell injury reduced supporting cell proliferation as well as the numbers of regenerated hair cells. By contrast, addition of recombinant human VEGFA to organ cultures caused an increase in both supporting cell division and hair cell regeneration. VEGF's effects on supporting cells were preserved in isolated supporting cell cultures, indicating that VEGF can act directly upon supporting cells. These observations demonstrate a heretofore uncharacterized function for VEGF signaling as a critical positive regulator of hair cell regeneration in the avian inner ear.
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Affiliation(s)
- Liangcai Wan
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology-Head and Neck Surgery, University of Washington, Seattle, WA, 98195, United States.
| | - Michael Lovett
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, United States.
| | - Mark E Warchol
- Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine, St. Louis, MO, 63110, United States.
| | - Jennifer S Stone
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology-Head and Neck Surgery, University of Washington, Seattle, WA, 98195, United States.
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29
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Kros CJ, Steyger PS. Aminoglycoside- and Cisplatin-Induced Ototoxicity: Mechanisms and Otoprotective Strategies. Cold Spring Harb Perspect Med 2019; 9:cshperspect.a033548. [PMID: 30559254 DOI: 10.1101/cshperspect.a033548] [Citation(s) in RCA: 98] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Ototoxicity refers to damage of inner ear structures (i.e., the cochlea and vestibule) and their function (hearing and balance) following exposure to specific in-hospital medications (i.e., aminoglycoside antibiotics, platinum-based drugs), as well as a variety of environmental or occupational exposures (e.g., metals and solvents). This review provides a narrative derived from relevant papers describing factors contributing to (or increasing the risk of) aminoglycoside and cisplatin-induced ototoxicity. We also review current strategies to protect against ototoxicity induced by these indispensable pharmacotherapeutic treatments for life-threatening infections and solid tumors. We end by highlighting several interventional strategies that are currently in development, as well as the diverse challenges that still need to be overcome to prevent drug-induced hearing loss.
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Affiliation(s)
- Corné J Kros
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, United Kingdom
| | - Peter S Steyger
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, Oregon 97239.,National Center for Rehabilitative Auditory Research, VA Portland Health Care System, Portland, Oregon 97239
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30
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AAV-ie enables safe and efficient gene transfer to inner ear cells. Nat Commun 2019; 10:3733. [PMID: 31427575 PMCID: PMC6700137 DOI: 10.1038/s41467-019-11687-8] [Citation(s) in RCA: 122] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 07/17/2019] [Indexed: 12/17/2022] Open
Abstract
Hearing loss is the most common sensory disorder. While gene therapy has emerged as a promising treatment of inherited diseases like hearing loss, it is dependent on the identification of gene delivery vectors. Adeno-associated virus (AAV) vector-mediated gene therapy has been approved in the US for treating a rare inherited eye disease but no safe and efficient vectors have been identified that can target the diverse types of inner ear cells. Here, we identify an AAV variant, AAV-inner ear (AAV-ie), for gene delivery in mouse inner ear. Our results show that AAV-ie transduces the cochlear supporting cells (SCs) with high efficiency, representing a vast improvement over conventional AAV serotypes. Furthermore, after AAV-ie-mediated transfer of the Atoh1 gene, we find that many SCs trans-differentiated into new HCs. Our results suggest that AAV-ie is a useful tool for the cochlear gene therapy and for investigating the mechanism of HC regeneration. There are currently few AAV vectors that can effectively target the diverse cell types of the inner ear. Here the authors design AAV-ie for gene delivery to the mouse cochlea, targeting cochlear supporting cells.
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31
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Wagner EL, Shin JB. Mechanisms of Hair Cell Damage and Repair. Trends Neurosci 2019; 42:414-424. [PMID: 30992136 DOI: 10.1016/j.tins.2019.03.006] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 03/04/2019] [Accepted: 03/13/2019] [Indexed: 01/22/2023]
Abstract
Sensory hair cells of the inner ear are exposed to continuous mechanical stress, causing damage over time. The maintenance of hair cells is further challenged by damage from a variety of other ototoxic factors, including loud noise, aging, genetic defects, and ototoxic drugs. This damage can manifest in many forms, from dysfunction of the hair cell mechanotransduction complex to loss of specialized ribbon synapses, and may even result in hair cell death. Given that mammalian hair cells do not regenerate, the repair of hair cell damage is important for continued auditory function throughout life. Here, we discuss how several key hair cell structures can be damaged, and what is known about how they are repaired.
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Affiliation(s)
- Elizabeth L Wagner
- Department of Neuroscience, University of Virginia-School of Medicine, Charlottesville, VA 22908, USA; Department of Biochemistry and Molecular Genetics, University of Virginia-School of Medicine, Charlottesville, VA 22908, USA
| | - Jung-Bum Shin
- Department of Neuroscience, University of Virginia-School of Medicine, Charlottesville, VA 22908, USA.
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32
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Lenz DR, Gunewardene N, Abdul-Aziz DE, Wang Q, Gibson TM, Edge ASB. Applications of Lgr5-Positive Cochlear Progenitors (LCPs) to the Study of Hair Cell Differentiation. Front Cell Dev Biol 2019; 7:14. [PMID: 30873406 PMCID: PMC6401656 DOI: 10.3389/fcell.2019.00014] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 01/31/2019] [Indexed: 01/05/2023] Open
Abstract
The mouse cochlea contains approximately 15,000 hair cells. Its dimensions and location, and the small number of hair cells, make mechanistic, developmental and cellular replacement studies difficult. We recently published a protocol to expand and differentiate murine neonatal cochlear progenitor cells into 3D organoids that recapitulate developmental pathways and can generate large numbers of hair cells with intact stereociliary bundles, molecular markers of the native cells and mechanotransduction channel activity, as indicated by FM1-43 uptake. Here, we elaborate on the method and application of these Lgr5-positive cochlear progenitors, termed LCPs, to the study of inner ear development and differentiation. We demonstrate the use of these cells for testing several drug candidates, gene silencing and overexpression, as well as genomic modification using CRISPR/Cas9. We thus establish LCPs as a valuable in vitro tool for the analysis of progenitor cell manipulation and hair cell differentiation.
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Affiliation(s)
- Danielle R Lenz
- Department of Otolaryngology, Harvard Medical School, Boston, MA, United States.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, MA, United States
| | - Niliksha Gunewardene
- Department of Otolaryngology, Harvard Medical School, Boston, MA, United States.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, MA, United States
| | - Dunia E Abdul-Aziz
- Department of Otolaryngology, Harvard Medical School, Boston, MA, United States.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, MA, United States
| | - Quan Wang
- Department of Otolaryngology, Harvard Medical School, Boston, MA, United States.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, MA, United States
| | - Tyler M Gibson
- Department of Otolaryngology, Harvard Medical School, Boston, MA, United States.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, MA, United States
| | - Albert S B Edge
- Department of Otolaryngology, Harvard Medical School, Boston, MA, United States.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, MA, United States.,Harvard Stem Cell Institute, Cambridge, MA, United States
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33
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Abstract
Hearing loss is present in millions of people worldwide. Current treatment for patients with severe to profound hearing loss consists of cochlear implantation. Providing the cochlear nerve is intact, patients generally benefit greatly from this intervention, frequently achieving significant improvements in speech comprehension. There are, however, some cases where current technology does not provide patients with adequate benefit. Ongoing research in cell transplantation and gene therapy promises to lead to new developments that will improve the function of cochlear implants. Translation of these experimental approaches is presently at an early stage. This review focuses on the application of biological therapies in severe hearing loss and discusses some of the barriers to translating basic scientific research into clinical reality. We emphasize the application of these novel therapies to cochlear implantation.
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Affiliation(s)
- A Roemer
- Klinik für Hals-Nasen-Ohren-Heilkunde OE 6500, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
| | - H Staecker
- Department of Otolaryngology - Head and Neck Surgery, University of Kansas School of Medicine, Kansas City, KS, USA
| | - S Sasse
- Klinik für Hals-Nasen-Ohren-Heilkunde OE 6500, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - T Lenarz
- Klinik für Hals-Nasen-Ohren-Heilkunde OE 6500, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - A Warnecke
- Klinik für Hals-Nasen-Ohren-Heilkunde OE 6500, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
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34
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Sirko P, Gale JE, Ashmore JF. Intercellular Ca 2+ signalling in the adult mouse cochlea. J Physiol 2018; 597:303-317. [PMID: 30318615 PMCID: PMC6312409 DOI: 10.1113/jp276400] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 10/12/2018] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Intercellular Ca2+ waves are increases in cytoplasmic Ca2+ levels that propagate between cells. Periodic Ca2+ waves have been linked to gene regulation and are thought to play a crucial role in the development of our hearing epithelium, the organ of Corti and the acquisition of hearing. We observed regular periodic intercellular Ca2+ waves in supporting cells of an ex vivo preparation of the adult mouse organ of Corti, and these waves were found to propagate independently of extracellular ATP and were inhibited by the gap junction blockers 1-octanol and carbenoxolone. Our results establish that the existence of periodic Ca2+ waves in the organ of Corti is not restricted to the prehearing period. ABSTRACT We have investigated wave-like cytoplasmic calcium (Ca2+ ) signalling in an ex vivo preparation of the adult mouse organ of Corti. Two types of intercellular Ca2+ waves that differ in propagation distance and speed were observed. One type was observed to travel up to 100 μm with an average velocity of 7 μm/s. Such waves were initiated by local tissue damage in the outer hair cell region. The propagation distance was decreased when the purinergic receptor antagonists pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS; 50 μm) or suramin (150 μm) were added to the extracellular buffer. Immunocytochemical analysis and experiments with calcium indicator dyes showed that both P2X and P2Y receptors were present in supporting cells. A second class of waves identified to travel longitudinally along the organ of Corti propagated at a lower velocity of 1-3 μm/s. These 'slow' Ca2+ waves were particularly evident in the inner sulcus and Deiters' cells. They travelled for distances of up to 500 μm. The slow Ca2+ signalling varied periodically (approximately one wave every 10 min) and was maintained for more than 3 h. The slow waves were not affected by apyrase, or by the P2 receptor agonists suramin (150 μm) or PPADS (50 μm) but were blocked by the connexin channel blockers octanol (1 mm) and carbenoxolone (100 μm). It is proposed that the observed Ca2+ waves might be a physiological response to a change in extracellular environment and may be involved in critical gene regulation activities in the supporting cells of the cochlea.
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Affiliation(s)
- Piotr Sirko
- UCL Ear Institute, 332 Gray's Inn Road, London, WC1X 8EE, UK
| | - Jonathan E Gale
- UCL Ear Institute, 332 Gray's Inn Road, London, WC1X 8EE, UK.,Department of Cell & Developmental Biology, UCL, Gower St., London, WC1E 6BT, UK
| | - Jonathan F Ashmore
- UCL Ear Institute, 332 Gray's Inn Road, London, WC1X 8EE, UK.,Department of Neuroscience, Physiology & Pharmacology, UCL, Gower St., London, WC1E 6BT, UK
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35
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Jiang L, Xu J, Jin R, Bai H, Zhang M, Yang S, Zhang X, Zhang X, Han Z, Zeng S. Transcriptomic analysis of chicken cochleae after gentamicin damage and the involvement of four signaling pathways (Notch, FGF, Wnt and BMP) in hair cell regeneration. Hear Res 2018; 361:66-79. [DOI: 10.1016/j.heares.2018.01.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 06/22/2017] [Accepted: 01/06/2018] [Indexed: 10/18/2022]
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Deafness and loss of cochlear hair cells in the absence of thyroid hormone transporters Slc16a2 (Mct8) and Slc16a10 (Mct10). Sci Rep 2018. [PMID: 29535325 PMCID: PMC5849681 DOI: 10.1038/s41598-018-22553-w] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Transmembrane proteins that mediate the cellular uptake or efflux of thyroid hormone potentially provide a key level of control over neurodevelopment. In humans, defects in one such protein, solute carrier SLC16A2 (MCT8) are associated with psychomotor retardation. Other proteins that transport the active form of thyroid hormone triiodothyronine (T3) or its precursor thyroxine (T4) have been identified in vitro but the wider significance of such transporters in vivo is unclear. The development of the auditory system requires thyroid hormone and the cochlea is a primary target tissue. We have proposed that the compartmental anatomy of the cochlea would necessitate transport mechanisms to convey blood-borne hormone to target tissues. We report hearing loss in mice with mutations in Slc16a2 and a related gene Slc16a10 (Mct10, Tat1). Deficiency of both transporters results in retarded development of the sensory epithelium similar to impairment caused by hypothyroidism, compounded with a progressive degeneration of cochlear hair cells and loss of endocochlear potential. Administration of T3 largely restores the development of the sensory epithelium and limited auditory function, indicating the T3-sensitivity of defects in the sensory epithelium. The results indicate a necessity for thyroid hormone transporters in cochlear development and function.
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Chambers AR, Pilati N, Balaram P, Large CH, Kaczmarek LK, Polley DB. Pharmacological modulation of Kv3.1 mitigates auditory midbrain temporal processing deficits following auditory nerve damage. Sci Rep 2017; 7:17496. [PMID: 29235497 PMCID: PMC5727503 DOI: 10.1038/s41598-017-17406-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 11/20/2017] [Indexed: 12/12/2022] Open
Abstract
Higher stages of central auditory processing compensate for a loss of cochlear nerve synapses by increasing the gain on remaining afferent inputs, thereby restoring firing rate codes for rudimentary sound features. The benefits of this compensatory plasticity are limited, as the recovery of precise temporal coding is comparatively modest. We reasoned that persistent temporal coding deficits could be ameliorated through modulation of voltage-gated potassium (Kv) channels that regulate temporal firing patterns. Here, we characterize AUT00063, a pharmacological compound that modulates Kv3.1, a high-threshold channel expressed in fast-spiking neurons throughout the central auditory pathway. Patch clamp recordings from auditory brainstem neurons and in silico modeling revealed that application of AUT00063 reduced action potential timing variability and improved temporal coding precision. Systemic injections of AUT00063 in vivo improved auditory synchronization and supported more accurate decoding of temporal sound features in the inferior colliculus and auditory cortex in adult mice with a near-complete loss of auditory nerve afferent synapses in the contralateral ear. These findings suggest modulating Kv3.1 in central neurons could be a promising therapeutic approach to mitigate temporal processing deficits that commonly accompany aging, tinnitus, ototoxic drug exposure or noise damage.
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Affiliation(s)
- Anna R Chambers
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, Boston, MA, USA.,Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Nadia Pilati
- Autifony SRL, Verona, Italy; and Autifony Therapeutics Limited, Imperial College Incubator, London, UK
| | - Pooja Balaram
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, Boston, MA, USA.,Department of Otolaryngology, Harvard Medical School, Boston, MA, USA
| | - Charles H Large
- Autifony SRL, Verona, Italy; and Autifony Therapeutics Limited, Imperial College Incubator, London, UK
| | - Leonard K Kaczmarek
- Departments of Pharmacology and Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, USA
| | - Daniel B Polley
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, Boston, MA, USA. .,Department of Otolaryngology, Harvard Medical School, Boston, MA, USA.
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38
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Regenerative medicine in hearing recovery. Cytotherapy 2017; 19:909-915. [DOI: 10.1016/j.jcyt.2017.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 03/24/2017] [Accepted: 04/21/2017] [Indexed: 12/20/2022]
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Abstract
The classic view of sensorineural hearing loss has been that the primary damage targets are hair cells and that auditory nerve loss is typically secondary to hair cell degeneration. Recent work has challenged that view. In noise-induced hearing loss, exposures causing only reversible threshold shifts (and no hair cell loss) nevertheless cause permanent loss of >50% of the synaptic connections between hair cells and the auditory nerve. Similarly, in age-related hearing loss, degeneration of cochlear synapses precedes both hair cell loss and threshold elevation. This primary neural degeneration has remained a "hidden hearing loss" for two reasons: 1) the neuronal cell bodies survive for years despite loss of synaptic connection with hair cells, and 2) the degeneration is selective for auditory nerve fibers with high thresholds. Although not required for threshold detection when quiet, these high-threshold fibers are critical for hearing in noisy environments. Research suggests that primary neural degeneration is an important contributor to the perceptual handicap in sensorineural hearing loss, and it may be key to the generation of tinnitus and other associated perceptual anomalies. In cases where the hair cells survive, neurotrophin therapies can elicit neurite outgrowth from surviving auditory neurons and re-establishment of their peripheral synapses; thus, treatments may be on the horizon.
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Affiliation(s)
- M Charles Liberman
- Department of Otolaryngology, Harvard Medical School, Eaton Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles St., Boston, MA, 02114, USA
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40
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Roemer A, Staecker H, Sasse S, Lenarz T, Warnecke A. [Biological therapies in otology. German version]. HNO 2017; 65:571-585. [PMID: 28204850 DOI: 10.1007/s00106-016-0304-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Millions of people worldwide suffer from hearing loss. Current treatment for patients with severe to profound hearing loss consists of cochlear implants. Providing the cochlear nerve is intact, patients generally benefit enormously from this intervention, frequently achieving significant improvements in speech comprehension. There are, however, some cases where current technology does not provide patients with adequate benefit. New therapeutic concepts based on cell transplantation and gene therapy are developing rapidly, at least in the research sector. Compared to the wealth of basic research available in this area, translation of these new experimental approaches into clinical application is presently at a very early stage. The current review focuses on translatable treatment concepts and discusses the barriers that need to be overcome in order to translate basic scientific research into clinical reality. Furthermore, the first examples of clinical application of biological therapies in severe hearing loss are presented, particularly in connection with cochlear implants.
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Affiliation(s)
- A Roemer
- Klinik für Hals-Nasen-Ohren-Heilkunde OE 6500 Hannover Medical School, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Deutschland.
| | - H Staecker
- Department of Otolaryngology - Head and Neck Surgery, University of Kansas School of Medicine, Kansas City, KS, USA
| | - S Sasse
- Klinik für Hals-Nasen-Ohren-Heilkunde OE 6500 Hannover Medical School, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Deutschland
| | - T Lenarz
- Klinik für Hals-Nasen-Ohren-Heilkunde OE 6500 Hannover Medical School, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Deutschland
| | - A Warnecke
- Klinik für Hals-Nasen-Ohren-Heilkunde OE 6500 Hannover Medical School, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Deutschland
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A synthetic AAV vector enables safe and efficient gene transfer to the mammalian inner ear. Nat Biotechnol 2017; 35:280-284. [PMID: 28165475 PMCID: PMC5340646 DOI: 10.1038/nbt.3781] [Citation(s) in RCA: 216] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 01/04/2017] [Indexed: 01/01/2023]
Abstract
Efforts to develop gene therapies for hearing loss have been hampered by the lack of safe, efficient, and clinically relevant delivery modalities1, 2. Here we demonstrate the safety and efficiency of Anc80L65, a rationally designed synthetic vector3, for transgene delivery to the mouse cochlea. Cochlear explants incubated with Anc80L65 encoding eGFP demonstrated high level transduction of inner and outer hair cells (60–100%). Injection of Anc80L65 through the round window membrane resulted in highly efficient transduction of inner and outer hair cells, a substantial improvement over conventional adeno-associated virus (AAV) vectors. Anc80L65 round window injection was well tolerated, as indicated by sensory cell function, hearing and vestibular function, and immunologic parameters. The ability of Anc80L65 to target outer hair cells at high rates, a requirement for restoration of complex auditory function, may enable future gene therapies for hearing and balance disorders.
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Lee S, Jeong HS, Cho HH. Atoh1 as a Coordinator of Sensory Hair Cell Development and Regeneration in the Cochlea. Chonnam Med J 2017; 53:37-46. [PMID: 28184337 PMCID: PMC5299128 DOI: 10.4068/cmj.2017.53.1.37] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 09/22/2016] [Accepted: 09/23/2016] [Indexed: 12/18/2022] Open
Abstract
Cochlear sensory hair cells (HCs) are crucial for hearing as mechanoreceptors of the auditory systems. Clarification of transcriptional regulation for the cochlear sensory HC development is crucial for the improvement of cell replacement therapies for hearing loss. Transcription factor Atoh1 is the key player during HC development and regeneration. In this review, we will focus on Atoh1 and its related signaling pathways (Notch, fibroblast growth factor, and Wnt/β-catenin signaling) involved in the development of cochlear sensory HCs. We will also discuss the potential applicability of these signals for the induction of HC regeneration.
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Affiliation(s)
- Sungsu Lee
- Department of Otolaryngology-Head and Neck Surgery, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, Korea.; Research Institute of Medical Sciences, Chonnam National University, Gwangju, Korea
| | - Han-Seong Jeong
- Research Institute of Medical Sciences, Chonnam National University, Gwangju, Korea.; Department of Physiology, Chonnam National University Medical School, Gwangju, Korea
| | - Hyong-Ho Cho
- Department of Otolaryngology-Head and Neck Surgery, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, Korea.; Research Institute of Medical Sciences, Chonnam National University, Gwangju, Korea
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43
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Maass JC, Gu R, Cai T, Wan YW, Cantellano SC, Asprer JST, Zhang H, Jen HI, Edlund RK, Liu Z, Groves AK. Transcriptomic Analysis of Mouse Cochlear Supporting Cell Maturation Reveals Large-Scale Changes in Notch Responsiveness Prior to the Onset of Hearing. PLoS One 2016; 11:e0167286. [PMID: 27918591 PMCID: PMC5137903 DOI: 10.1371/journal.pone.0167286] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 11/13/2016] [Indexed: 01/22/2023] Open
Abstract
Neonatal mouse cochlear supporting cells have a limited ability to divide and trans-differentiate into hair cells, but this ability declines rapidly in the two weeks after birth. This decline is concomitant with the morphological and functional maturation of the organ of Corti prior to the onset of hearing. However, despite this association between maturation and loss of regenerative potential, little is known of the molecular changes that underlie these events. To identify these changes, we used RNA-seq to generate transcriptional profiles of purified cochlear supporting cells from 1- and 6-day-old mice. We found many significant changes in gene expression during this period, many of which were related to regulation of proliferation, differentiation of inner ear components and the maturation of the organ of Corti prior to the onset of hearing. One example of a change in regenerative potential of supporting cells is their robust production of hair cells in response to a blockade of the Notch signaling pathway at the time of birth, but a complete lack of response to such blockade just a few days later. By comparing our supporting cell transcriptomes to those of supporting cells cultured in the presence of Notch pathway inhibitors, we show that the transcriptional response to Notch blockade disappears almost completely in the first postnatal week. Our results offer some of the first molecular insights into the failure of hair cell regeneration in the mammalian cochlea.
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Affiliation(s)
- Juan C. Maass
- Department of Otolaryngology, Hospital Clínico Universidad de Chile and Interdisciplinary Program of Physiology and Biophysics ICBM Universidad de Chile, Santiago, Chile
- Department of Otolaryngology, Clínica Alemana de Santiago, Facultad de Medicina Clínica Alemana-Universidad del Desarrollo, Santiago, Chile
| | - Rende Gu
- Department of Neuroscience, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, United States of America
| | - Tiantian Cai
- Department of Neuroscience, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, United States of America
| | - Ying-Wooi Wan
- Department of Pediatrics, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, United States of America
- The Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States of America
| | - Silvia C. Cantellano
- Department of Otolaryngology, Hospital Clínico Universidad de Chile and Interdisciplinary Program of Physiology and Biophysics ICBM Universidad de Chile, Santiago, Chile
| | - Joanna S. T. Asprer
- Department of Neuroscience, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, United States of America
| | - Hongyuan Zhang
- Department of Neuroscience, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, United States of America
| | - Hsin-I Jen
- Program in Developmental Biology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, United States of America
| | - Renée K. Edlund
- Department of Neuroscience, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, United States of America
| | - Zhandong Liu
- Department of Pediatrics, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, United States of America
- The Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States of America
| | - Andrew K. Groves
- Department of Neuroscience, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, United States of America
- Program in Developmental Biology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, United States of America
- Department of Molecular and Human Genetics, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, United States of America
- * E-mail:
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44
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Krauss SR, de Haan G. Epigenetic perturbations in aging stem cells. Mamm Genome 2016; 27:396-406. [PMID: 27229519 PMCID: PMC4935734 DOI: 10.1007/s00335-016-9645-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 05/10/2016] [Indexed: 12/29/2022]
Abstract
Stem cells maintain homeostasis in all regenerating tissues during the lifespan of an organism. Thus, age-related functional decline of such tissues is likely to be at least partially explained by molecular events occurring in the stem cell compartment. Some of these events involve epigenetic changes, which may dictate how an aging genome can lead to differential gene expression programs. Recent technological advances have made it now possible to assess the genome-wide distribution of an ever-increasing number of epigenetic marks. As a result, the hypothesis that there may be a causal role for an altered epigenome contributing to the functional decline of cells, tissues, and organs in aging organisms can now be explored. In this paper, we review recent developments in the field of epigenetic regulation of stem cells, and how this may contribute to aging.
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Affiliation(s)
- Sara Russo Krauss
- Department of Ageing Biology and Stem Cells, European Research Institute for the Biology of Ageing, University Medical Centre Groningen, University of Groningen, Antonius Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Gerald de Haan
- Department of Ageing Biology and Stem Cells, European Research Institute for the Biology of Ageing, University Medical Centre Groningen, University of Groningen, Antonius Deusinglaan 1, 9713 AV, Groningen, The Netherlands.
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45
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Kim MA, Cho HJ, Bae SH, Lee B, Oh SK, Kwon TJ, Ryoo ZY, Kim HY, Cho JH, Kim UK, Lee KY. Methionine Sulfoxide Reductase B3-Targeted In Utero Gene Therapy Rescues Hearing Function in a Mouse Model of Congenital Sensorineural Hearing Loss. Antioxid Redox Signal 2016; 24:590-602. [PMID: 26649646 PMCID: PMC4840920 DOI: 10.1089/ars.2015.6442] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 11/18/2015] [Accepted: 12/07/2015] [Indexed: 11/12/2022]
Abstract
AIMS Methionine sulfoxide reductase B3 (MsrB3), which stereospecifically repairs methionine-R-sulfoxide, is an important Msr protein that is associated with auditory function in mammals. MsrB3 deficiency leads to profound congenital hearing loss due to the degeneration of stereociliary bundles and the apoptotic death of cochlear hair cells. In this study, we investigated a fundamental treatment strategy in an MsrB3 deficiency mouse model and confirmed the biological significance of MsrB3 in the inner ear using MsrB3 knockout (MsrB3(-/-)) mice. RESULTS We delivered a recombinant adeno-associated virus encoding the MsrB3 gene directly into the otocyst at embryonic day 12.5 using a transuterine approach. We observed hearing recovery in the treated ears of MsrB3(-/-) mice at postnatal day 28, and we confirmed MsrB3 mRNA and protein expression in cochlear extracts. Additionally, we demonstrated that the morphology of the stereociliary bundles in the rescued ears of MsrB3(-/-) mice was similar to those in MsrB3(+/+) mice. INNOVATION To our knowledge, this is the first study to demonstrate functional and morphological rescue of the hair cells of the inner ear in the MsrB3 deficiency mouse model of congenital genetic sensorineural hearing loss using an in utero, virus-mediated gene therapy approach. CONCLUSION Our results provide insight into the role of MsrB3 in hearing function and bring us one step closer to hearing restoration as a fundamental therapy.
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Affiliation(s)
- Min-A Kim
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea
- School of Life Sciences, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, Daegu, Republic of Korea
| | - Hyun-Ju Cho
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea
| | - Seung-Hyun Bae
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea
- School of Life Sciences, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, Daegu, Republic of Korea
| | - Byeonghyeon Lee
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea
- School of Life Sciences, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, Daegu, Republic of Korea
| | - Se-Kyung Oh
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea
- School of Life Sciences, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, Daegu, Republic of Korea
- Division of Life Sciences, Korea Polar Research Institute (KOPRI), Incheon, Republic of Korea
| | - Tae-Jun Kwon
- Laboratory Animal Center, Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF), Daegu, Republic of Korea
| | - Zae-Young Ryoo
- School of Life Science and Biotechnology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea
| | - Hwa-Young Kim
- Department of Biochemistry and Molecular Biology, Yeungnam University College of Medicine, Daegu, Republic of Korea
| | - Jin-Ho Cho
- Department of Electronic Engineering, College of IT Engineering, Kyungpook National University, Daegu, Republic of Korea
| | - Un-Kyung Kim
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea
- School of Life Sciences, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, Daegu, Republic of Korea
| | - Kyu-Yup Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
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46
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Brosel S, Laub C, Averdam A, Bender A, Elstner M. Molecular aging of the mammalian vestibular system. Ageing Res Rev 2016; 26:72-80. [PMID: 26739358 DOI: 10.1016/j.arr.2015.12.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 12/16/2015] [Accepted: 12/21/2015] [Indexed: 12/18/2022]
Abstract
Dizziness and imbalance frequently affect the elderly and contribute to falls and frailty. In many geriatric patients, clinical testing uncovers a dysfunction of the vestibular system, but no specific etiology can be identified. Neuropathological studies have demonstrated age-related degeneration of peripheral and central vestibular neurons, but the molecular mechanisms are poorly understood. In contrast, recent studies into age-related hearing loss strongly implicate mitochondrial dysfunction, oxidative stress and apoptotic cell death of cochlear hair cells. While some data suggest that analogous biological pathomechanisms may underlie vestibular dysfunction, actual proof is missing. In this review, we summarize the available data on the molecular causes of vestibular dysfunction.
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Affiliation(s)
- Sonja Brosel
- German Center for Vertigo and Balance Disorders, Department of Neurology, Klinikum Grosshadern, Ludwig-Maximilians-University, Marchioninistr. 15, 81377 Munich, Germany.
| | - Christoph Laub
- Department of Neurology with Friedrich-Baur-Institute, Klinikum Grosshadern, Ludwig-Maximilians-University, Marchioninistr. 15, 81377 Munich, Germany
| | - Anne Averdam
- Department of Neurology with Friedrich-Baur-Institute, Klinikum Grosshadern, Ludwig-Maximilians-University, Marchioninistr. 15, 81377 Munich, Germany
| | - Andreas Bender
- Department of Neurology, Therapiezentrum Burgau, Kapuzinerstr.34, 89331 Burgau, Germany
| | - Matthias Elstner
- Department of Neurology with Friedrich-Baur-Institute, Klinikum Grosshadern, Ludwig-Maximilians-University, Marchioninistr. 15, 81377 Munich, Germany; Department of Neurology and Clinical Neurophysiology, Academic Hospital Munich-Bogenhausen, Technical University of Munich, Englschalkingerstr. 77, 81925 Munich, Germany
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47
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Stojanova ZP, Kwan T, Segil N. Epigenetic regulation of Atoh1 guides hair cell development in the mammalian cochlea. Development 2016; 142:3529-36. [PMID: 26487780 DOI: 10.1242/dev.126763] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
In the developing cochlea, sensory hair cell differentiation depends on the regulated expression of the bHLH transcription factor Atoh1. In mammals, if hair cells die they do not regenerate, leading to permanent deafness. By contrast, in non-mammalian vertebrates robust regeneration occurs through upregulation of Atoh1 in the surviving supporting cells that surround hair cells, leading to functional recovery. Investigation of crucial transcriptional events in the developing organ of Corti, including those involving Atoh1, has been hampered by limited accessibility to purified populations of the small number of cells present in the inner ear. We used µChIP and qPCR assays of FACS-purified cells to track changes in the epigenetic status of the Atoh1 locus during sensory epithelia development in the mouse. Dynamic changes in the histone modifications H3K4me3/H3K27me3, H3K9ac and H3K9me3 reveal a progression from poised, to active, to repressive marks, correlating with the onset of Atoh1 expression and its subsequent silencing during the perinatal (P1 to P6) period. Inhibition of acetylation blocked the increase in Atoh1 mRNA in nascent hair cells, as well as ongoing hair cell differentiation during embryonic organ of Corti development ex vivo. These results reveal an epigenetic mechanism of Atoh1 regulation underlying hair cell differentiation and subsequent maturation. Interestingly, the H3K4me3/H3K27me3 bivalent chromatin structure observed in progenitors persists at the Atoh1 locus in perinatal supporting cells, suggesting an explanation for the latent capacity of these cells to transdifferentiate into hair cells, and highlighting their potential as therapeutic targets in hair cell regeneration.
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Affiliation(s)
- Zlatka P Stojanova
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of the University of Southern California, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research at USC, 1425 San Pablo St., Los Angeles, CA 90033, USA
| | - Tao Kwan
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of the University of Southern California, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research at USC, 1425 San Pablo St., Los Angeles, CA 90033, USA
| | - Neil Segil
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of the University of Southern California, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research at USC, 1425 San Pablo St., Los Angeles, CA 90033, USA Caruso Department of Otolaryngology, Keck School of Medicine of the University of Southern California, Suite 5100, 1450 San Pablo Street, Los Angeles, CA 90033, USA
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48
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Azadeh J, Song Z, Laureano AS, Toro-Ramos A, Kwan K. Initiating Differentiation in Immortalized Multipotent Otic Progenitor Cells. J Vis Exp 2016. [PMID: 26780605 DOI: 10.3791/53692] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Use of human induced pluripotent stem cells (iPSC) or embryonic stem cells (ESC) for cell replacement therapies holds great promise. Several limitations including low yields and heterogeneous populations of differentiated cells hinder the progress of stem cell therapies. A fate restricted immortalized multipotent otic progenitor (iMOP) cell line was generated to facilitate efficient differentiation of large numbers of functional hair cells and spiral ganglion neurons (SGN) for inner ear cell replacement therapies. Starting from dissociated cultures of single iMOP cells, protocols that promote cell cycle exit and differentiation by basic fibroblast growth factor (bFGF) withdrawal were described. A significant decrease in proliferating cells after bFGF withdrawal was confirmed using an EdU cell proliferation assay. Concomitant with a decrease in proliferation, successful differentiation resulted in expression of molecular markers and morphological changes. Immunostaining of Cdkn1b (p27(KIP)) and Cdh1 (E-cadherin) in iMOP-derived otospheres was used as an indicator for differentiation into inner ear sensory epithelia while immunostaining of Cdkn1b and Tubb3 (neuronal β-tubulin) was used to identify iMOP-derived neurons. Use of iMOP cells provides an important tool for understanding cell fate decisions made by inner ear neurosensory progenitors and will help develop protocols for generating large numbers of iPSC or ESC-derived hair cells and SGNs. These methods will accelerate efforts for generating otic cells for replacement therapies.
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Affiliation(s)
| | | | | | | | - Kelvin Kwan
- Cell Biology & Neuroscience, Rutgers University;
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Fan C, Zou S, Wang J, Zhang B, Song J. Neomycin damage and regeneration of hair cells in both mechanoreceptor and electroreceptor lateral line organs of the larval Siberian sturgeon (Acipenser baerii
). J Comp Neurol 2015; 524:1443-56. [DOI: 10.1002/cne.23918] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 10/16/2015] [Accepted: 10/17/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Chunxin Fan
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education; Shanghai China
- Institute for Marine Biosystem and Neuroscience, International Center for Marine Studies, Shanghai Ocean University; Shanghai China
| | - Sha Zou
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education; Shanghai China
- Institute for Marine Biosystem and Neuroscience, International Center for Marine Studies, Shanghai Ocean University; Shanghai China
| | - Jian Wang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education; Shanghai China
| | - Bo Zhang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education; Shanghai China
- Institute for Marine Biosystem and Neuroscience, International Center for Marine Studies, Shanghai Ocean University; Shanghai China
| | - Jiakun Song
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education; Shanghai China
- Institute for Marine Biosystem and Neuroscience, International Center for Marine Studies, Shanghai Ocean University; Shanghai China
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Goutman JD, Elgoyhen AB, Gómez-Casati ME. Cochlear hair cells: The sound-sensing machines. FEBS Lett 2015; 589:3354-61. [PMID: 26335749 PMCID: PMC4641020 DOI: 10.1016/j.febslet.2015.08.030] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 08/18/2015] [Accepted: 08/19/2015] [Indexed: 12/20/2022]
Abstract
The sensory epithelium of the mammalian inner ear contains two types of mechanosensory cells: inner (IHC) and outer hair cells (OHC). They both transduce mechanical force generated by sound waves into electrical signals. In their apical end, these cells possess a set of stereocilia representing the mechanosensing organelles. IHC are responsible for detecting sounds and transmitting the acoustic information to the brain by converting graded depolarization into trains of action potentials in auditory nerve fibers. OHC are responsible for the active mechanical amplification process that leads to the fine tuning and high sensitivity of the mammalian inner ear. This active amplification is the consequence of the ability of OHC to alter their cell length in response to changes in membrane potential, and is controlled by an efferent inhibitory innervation. Medial olivocochlear efferent fibers, originating in the brainstem, synapse directly at the base of OHC and release acetylcholine. A very special type of nicotinic receptor, assembled by α9α10 subunits, participates in this synapse. Here we review recent knowledge and the role of both afferent and efferent synapse in the inner ear.
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Affiliation(s)
- Juan D Goutman
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, "Dr. Héctor N Torres" (CONICET-UBA), Vuelta de Obligado 2490, Buenos Aires, Argentina.
| | - A Belén Elgoyhen
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, "Dr. Héctor N Torres" (CONICET-UBA), Vuelta de Obligado 2490, Buenos Aires, Argentina; Tercera Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, Buenos Aires, Argentina
| | - María Eugenia Gómez-Casati
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, "Dr. Héctor N Torres" (CONICET-UBA), Vuelta de Obligado 2490, Buenos Aires, Argentina; Tercera Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, Buenos Aires, Argentina.
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