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Abbas M, Wang J, Leboucq N, Mondain M, Blanc F. Cochlear Aqueduct Post-Natal Growth: A Computed Tomography Study. J Assoc Res Otolaryngol 2024:10.1007/s10162-024-00963-0. [PMID: 39294515 DOI: 10.1007/s10162-024-00963-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Accepted: 08/10/2024] [Indexed: 09/20/2024] Open
Abstract
The cochlear aqueduct (CA) is a bony canal located at the base of the scala tympani of the cochlea. It connects the inner ear perilymph fluid to the cerebrospinal fluid of the posterior cerebral fossa. Its function is not well understood, as it seems to be patent in only a fraction of adult patients. Indirect observations argue in favor of the CA being more patent in children. To study the CA morphology in children, we performed a retrospective single-center study of 85 high-resolution temporal bone computed tomography (hrCT) scans of children with a mean age of 3.23 ± 3.07 years (13 days of life up to 18 years), and compared them with a group of 22 adult hrCT (mean age of 24.01 ± 3.58 years). The CA morphology measurements included its total length, its funnel (wider intracranial portion) length and width and its type (indicating its radiological patency), according to a previously published classification. The dimensions of the CA were significantly smaller in children compared with adults for the axial length (10.37 ± 2.58 versus 14.63 ± 2.40 mm, respectively, p < 0,001) and the funnel length (3.94 ± 1.59 versus 6.01 ± 1.77 mm, respectively, p < 0,001). The funnel width tended to be smaller but the difference was not significant: 3.49 ± 1,33 versus 3.89 ± 1.07 mm, p = 0,22. The repartition of types of CA was also statistically different. The CA appeared to be more identifiable in the children population. Type 1 (CA visible along its entire course) accounted for 42% (36/85) of children and only 5% (1/22) of adults, type 2 (visible in the medial two thirds) for 30% (25/85) versus 31% (7/22), type 3 (not visible completely along the medial two thirds) for 27% (23/85) versus 50% (11/22). Finally, type 4 (undetectable) was found in only 1% (1/85) of children and 14% (3/22) of adults (p < 0,001). Our study showed significant postnatal growth of the length of the CA, which was more rapid before the age of 2, and slowed after 6 years of age. Its width increased less, with children older than 2 years presenting a similar width to adults. The CA was more identifiable in hrCT in children, arguing for a more permeable tract. The number of completely ossified CA was significantly lower in the children population. These findings highlight the differences between the CA morphology in adults and children and raise the question of differences in function. Moreover, these differences may impact the pharmacodynamics of drugs or vectors delivered into the pediatric inner ear. Further studies are required, both on the anatomy of temporal bones and on the function of the CA in children.
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Affiliation(s)
- Maha Abbas
- Department of Otolaryngology and Head and Neck Surgery, Gui de Chauliac Hospital, CHRU Montpellier - Centre Hospitalier Régional Universitaire, Université de Montpellier, Montpellier, France
| | - Jing Wang
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM U1298, Montpellier, France
| | - Nicolas Leboucq
- Department of Neuroradiology, Gui de Chauliac Hospital, CHRU Montpellier - Centre Hospitalier Régional Universitaire, Université de Montpellier, Montpellier, France
| | - Michel Mondain
- Department of Otolaryngology and Head and Neck Surgery, Gui de Chauliac Hospital, CHRU Montpellier - Centre Hospitalier Régional Universitaire, Université de Montpellier, Montpellier, France
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM U1298, Montpellier, France
| | - Fabian Blanc
- Department of Otolaryngology and Head and Neck Surgery, Gui de Chauliac Hospital, CHRU Montpellier - Centre Hospitalier Régional Universitaire, Université de Montpellier, Montpellier, France.
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM U1298, Montpellier, France.
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Deng L, Wen C, Yu Y, Li Y, Liu H, Fu X, Cheng X, Huang L. A novel mutation in the OTOF gene in a Chinese family with auditory neuropathy. Intractable Rare Dis Res 2024; 13:104-109. [PMID: 38836175 PMCID: PMC11145404 DOI: 10.5582/irdr.2024.01004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 05/15/2024] [Accepted: 05/17/2024] [Indexed: 06/06/2024] Open
Abstract
Gene therapy for monogenic auditory neuropathy (AN) has successfully improved hearing function in target gene-deficient mice. Accurate genetic diagnosis can not only clarify the etiology but also accurately locate the lesion site, providing a basis for gene therapy and guiding patient intervention and management strategies. In this study, we collected data from a family with a pair of sisters with prelingual deafness. According to their auditory tests, subject Ⅱ-1 was diagnosed with profound sensorineural hearing loss (SNHL), Ⅱ-2 was diagnosed with AN, Ⅰ-1 was diagnosed with high-frequency SNHL, and Ⅰ-2 had normal hearing. Using whole-exome sequencing (WES), one nonsense mutation, c.4030C>T (p.R1344X), and one missense mutation, c.5000C>A (p.A1667D), in the OTOF (NM_001287489.1) gene were identified in the two siblings. Their parents were heterozygous carriers of c.5000C>A (father) and c.4030C>T (mother). We hypothesized that c.5000C>A is a novel pathogenic mutation. Thus, subject Ⅱ-1 should also be diagnosed with AN caused by OTOF mutations. These findings not only expand the OTOF gene mutation spectrum for AN but also indicate that WES is an effective approach for accurately diagnosing AN.
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Affiliation(s)
- Lin Deng
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Otolaryngology, Beijing, China
- Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University), Ministry of Education, Beijing, China
| | - Cheng Wen
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Otolaryngology, Beijing, China
- Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University), Ministry of Education, Beijing, China
| | - Yiding Yu
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Otolaryngology, Beijing, China
- Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University), Ministry of Education, Beijing, China
| | - Yue Li
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Otolaryngology, Beijing, China
- Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University), Ministry of Education, Beijing, China
| | - Hui Liu
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Otolaryngology, Beijing, China
- Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University), Ministry of Education, Beijing, China
| | - Xinxing Fu
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Otolaryngology, Beijing, China
- Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University), Ministry of Education, Beijing, China
| | - Xiaohua Cheng
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Otolaryngology, Beijing, China
- Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University), Ministry of Education, Beijing, China
| | - Lihui Huang
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Otolaryngology, Beijing, China
- Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University), Ministry of Education, Beijing, China
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3
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Li L, Shen T, Liu S, Qi J, Zhao Y. Advancements and future prospects of adeno-associated virus-mediated gene therapy for sensorineural hearing loss. Front Neurosci 2024; 18:1272786. [PMID: 38327848 PMCID: PMC10847333 DOI: 10.3389/fnins.2024.1272786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 01/12/2024] [Indexed: 02/09/2024] Open
Abstract
Sensorineural hearing loss (SNHL), a highly prevalent sensory impairment, results from a multifaceted interaction of genetic and environmental factors. As we continually gain insights into the molecular basis of auditory development and the growing compendium of deafness genes identified, research on gene therapy for SNHL has significantly deepened. Adeno-associated virus (AAV), considered a relatively secure vector for gene therapy in clinical trials, can deliver various transgenes based on gene therapy strategies such as gene replacement, gene silencing, gene editing, or gene addition to alleviate diverse types of SNHL. This review delved into the preclinical advances in AAV-based gene therapy for SNHL, spanning hereditary and acquired types. Particular focus is placed on the dual-AAV construction method and its application, the vector delivery route of mouse inner ear models (local, systemic, fetal, and cerebrospinal fluid administration), and the significant considerations in transforming from AAV-based animal model inner ear gene therapy to clinical implementation.
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Affiliation(s)
- Linke Li
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Tian Shen
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Shixi Liu
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Jieyu Qi
- State Key Laboratory of Bioelectronics, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Yu Zhao
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, China
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Hahn R, Avraham KB. Gene Therapy for Inherited Hearing Loss: Updates and Remaining Challenges. Audiol Res 2023; 13:952-966. [PMID: 38131808 PMCID: PMC10740825 DOI: 10.3390/audiolres13060083] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/13/2023] [Accepted: 11/24/2023] [Indexed: 12/23/2023] Open
Abstract
Hearing loss stands as the most prevalent sensory deficit among humans, posing a significant global health challenge. Projections indicate that by 2050, approximately 10% of the world's population will grapple with disabling hearing impairment. While approximately half of congenital hearing loss cases have a genetic etiology, traditional interventions such as hearing aids and cochlear implants do not completely restore normal hearing. The absence of biological treatment has prompted significant efforts in recent years, with a strong focus on gene therapy to address hereditary hearing loss. Although several studies have exhibited promising recovery from common forms of genetic deafness in mouse models, existing challenges must be overcome to make gene therapy applicable in the near future. Herein, we summarize the primary gene therapy strategies employed over past years, provide an overview of the recent achievements in preclinical studies for genetic hearing loss, and outline the current key obstacles to cochlear gene therapy.
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Affiliation(s)
| | - Karen B. Avraham
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel;
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5
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Petit C, Bonnet C, Safieddine S. Deafness: from genetic architecture to gene therapy. Nat Rev Genet 2023; 24:665-686. [PMID: 37173518 DOI: 10.1038/s41576-023-00597-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/27/2023] [Indexed: 05/15/2023]
Abstract
Progress in deciphering the genetic architecture of human sensorineural hearing impairment (SNHI) or loss, and multidisciplinary studies of mouse models, have led to the elucidation of the molecular mechanisms underlying auditory system function, primarily in the cochlea, the mammalian hearing organ. These studies have provided unparalleled insights into the pathophysiological processes involved in SNHI, paving the way for the development of inner-ear gene therapy based on gene replacement, gene augmentation or gene editing. The application of these approaches in preclinical studies over the past decade has highlighted key translational opportunities and challenges for achieving effective, safe and sustained inner-ear gene therapy to prevent or cure monogenic forms of SNHI and associated balance disorders.
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Affiliation(s)
- Christine Petit
- Institut Pasteur, Université Paris Cité, Inserm, Institut de l'Audition, F-75012, Paris, France.
- Collège de France, F-75005, Paris, France.
| | - Crystel Bonnet
- Institut Pasteur, Université Paris Cité, Inserm, Institut de l'Audition, F-75012, Paris, France
| | - Saaïd Safieddine
- Institut Pasteur, Université Paris Cité, Inserm, Institut de l'Audition, F-75012, Paris, France
- Centre National de la Recherche Scientifique, F-75016, Paris, France
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6
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Ivanchenko MV, Corey DP. Finding a window for gene therapy for hereditary deafness. Proc Natl Acad Sci U S A 2023; 120:e2311864120. [PMID: 37703299 PMCID: PMC10523573 DOI: 10.1073/pnas.2311864120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/15/2023] Open
Affiliation(s)
| | - David P. Corey
- Department of Neurobiology, Harvard Medical School, Boston, MA02115
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7
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Isgrig K, Cartagena-Rivera AX, Wang HJ, Grati M, Fernandez KA, Friedman TB, Belyantseva IA, Chien W. Combined AAV-mediated gene replacement therapy improves auditory function in a mouse model of human DFNB42 deafness. Mol Ther 2023; 31:2783-2795. [PMID: 37481704 PMCID: PMC10492026 DOI: 10.1016/j.ymthe.2023.07.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 05/30/2023] [Accepted: 07/19/2023] [Indexed: 07/24/2023] Open
Abstract
Hearing loss is a common disorder affecting nearly 20% of the world's population. Recently, studies have shown that inner ear gene therapy can improve auditory function in several mouse models of hereditary hearing loss. In most of these studies, the underlying mutations affect only a small number of cell types of the inner ear (e.g., sensory hair cells). Here, we applied inner ear gene therapy to the Ildr1Gt(D178D03)Wrst (Ildr1w-/-) mouse, a model of human DFNB42, non-syndromic autosomal recessive hereditary hearing loss associated with ILDR1 variants. ILDR1 is an integral protein of the tricellular tight junction complex and is expressed by diverse inner ear cell types in the organ of Corti and the cochlear lateral wall. We simultaneously applied two synthetic adeno-associated viruses (AAVs) with different tropism to deliver Ildr1 cDNA to the Ildr1w-/- mouse inner ear: one targeting the organ of Corti (AAV2.7m8) and the other targeting the cochlear lateral wall (AAV8BP2). We showed that combined AAV2.7m8/AAV8BP2 gene therapy improves cochlear structural integrity and auditory function in Ildr1w-/- mice.
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Affiliation(s)
- Kevin Isgrig
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Alexander X Cartagena-Rivera
- Section on Mechanobiology, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Hong Jun Wang
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Mhamed Grati
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Katharine A Fernandez
- Section on Sensory Cell Biology, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Thomas B Friedman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Inna A Belyantseva
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Wade Chien
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA; Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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8
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Amariutei AE, Jeng JY, Safieddine S, Marcotti W. Recent advances and future challenges in gene therapy for hearing loss. ROYAL SOCIETY OPEN SCIENCE 2023; 10:230644. [PMID: 37325593 PMCID: PMC10265000 DOI: 10.1098/rsos.230644] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 05/19/2023] [Indexed: 06/17/2023]
Abstract
Hearing loss is the most common sensory deficit experienced by humans and represents one of the largest chronic health conditions worldwide. It is expected that around 10% of the world's population will be affected by disabling hearing impairment by 2050. Hereditary hearing loss accounts for most of the known forms of congenital deafness, and over 25% of adult-onset or progressive hearing loss. Despite the identification of well over 130 genes associated with deafness, there is currently no curative treatment for inherited deafness. Recently, several pre-clinical studies in mice that exhibit key features of human deafness have shown promising hearing recovery through gene therapy involving the replacement of the defective gene with a functional one. Although the potential application of this therapeutic approach to humans is closer than ever, substantial further challenges need to be overcome, including testing the safety and longevity of the treatment, identifying critical therapeutic time windows and improving the efficiency of the treatment. Herein, we provide an overview of the recent advances in gene therapy and highlight the current hurdles that the scientific community need to overcome to ensure a safe and secure implementation of this therapeutic approach in clinical trials.
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Affiliation(s)
- Ana E. Amariutei
- School of Biomedical Science, University of Sheffield, Sheffield S10 2TN, UK
| | - Jing-Yi Jeng
- School of Biomedical Science, University of Sheffield, Sheffield S10 2TN, UK
| | - Saaid Safieddine
- Institut Pasteur, Université Paris Cité, Inserm, Institut de l'Audition, F-75012 Paris, France
| | - Walter Marcotti
- School of Biomedical Science, University of Sheffield, Sheffield S10 2TN, UK
- Neuroscience Institute, University of Sheffield, Sheffield S10 2TN, UK
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Jiang L, Wang D, He Y, Shu Y. Advances in gene therapy hold promise for treating hereditary hearing loss. Mol Ther 2023; 31:934-950. [PMID: 36755494 PMCID: PMC10124073 DOI: 10.1016/j.ymthe.2023.02.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/30/2023] [Accepted: 02/03/2023] [Indexed: 02/10/2023] Open
Abstract
Gene therapy focuses on genetic modification to produce therapeutic effects or treat diseases by repairing or reconstructing genetic material, thus being expected to be the most promising therapeutic strategy for genetic disorders. Due to the growing attention to hearing impairment, an increasing amount of research is attempting to utilize gene therapy for hereditary hearing loss (HHL), an important monogenic disease and the most common type of congenital deafness. Several gene therapy clinical trials for HHL have recently been approved, and, additionally, CRISPR-Cas tools have been attempted for HHL treatment. Therefore, in order to further advance the development of inner ear gene therapy and promote its broad application in other forms of genetic disease, it is imperative to review the progress of gene therapy for HHL. Herein, we address three main gene therapy strategies (gene replacement, gene suppression, and gene editing), summarizing the strategy that is most appropriate for particular monogenic diseases based on different pathogenic mechanisms, and then focusing on their successful applications for HHL in preclinical trials. Finally, we elaborate on the challenges and outlooks of gene therapy for HHL.
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Affiliation(s)
- Luoying Jiang
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China; Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Daqi Wang
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China; Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Yingzi He
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China.
| | - Yilai Shu
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China; Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China.
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10
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Saidia AR, Ruel J, Bahloul A, Chaix B, Venail F, Wang J. Current Advances in Gene Therapies of Genetic Auditory Neuropathy Spectrum Disorder. J Clin Med 2023; 12:jcm12030738. [PMID: 36769387 PMCID: PMC9918155 DOI: 10.3390/jcm12030738] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/11/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
Auditory neuropathy spectrum disorder (ANSD) refers to a range of hearing impairments characterized by an impaired transmission of sound from the cochlea to the brain. This defect can be due to a lesion or defect in the inner hair cell (IHC), IHC ribbon synapse (e.g., pre-synaptic release of glutamate), postsynaptic terminals of the spiral ganglion neurons, or demyelination and axonal loss within the auditory nerve. To date, the only clinical treatment options for ANSD are hearing aids and cochlear implantation. However, despite the advances in hearing-aid and cochlear-implant technologies, the quality of perceived sound still cannot match that of the normal ear. Recent advanced genetic diagnostics and clinical audiology made it possible to identify the precise site of a lesion and to characterize the specific disease mechanisms of ANSD, thus bringing renewed hope to the treatment or prevention of auditory neurodegeneration. Moreover, genetic routes involving the replacement or corrective editing of mutant sequences or defected genes to repair damaged cells for the future restoration of hearing in deaf people are showing promise. In this review, we provide an update on recent discoveries in the molecular pathophysiology of genetic lesions, auditory synaptopathy and neuropathy, and gene-therapy research towards hearing restoration in rodent models and in clinical trials.
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Affiliation(s)
- Anissa Rym Saidia
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34295 Montpellier, France
| | - Jérôme Ruel
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34295 Montpellier, France
- Cognitive Neuroscience Laboratory, Aix-Marseille University, CNRS, UMR 7291, 13331 Marseille, France
| | - Amel Bahloul
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34295 Montpellier, France
| | - Benjamin Chaix
- Department of ENT and Head and Neck Surgery, University Hospital of Montpellier, 34295 Montpellier, France
| | - Frédéric Venail
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34295 Montpellier, France
- Department of ENT and Head and Neck Surgery, University Hospital of Montpellier, 34295 Montpellier, France
| | - Jing Wang
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34295 Montpellier, France
- Department of ENT and Head and Neck Surgery, University Hospital of Montpellier, 34295 Montpellier, France
- Correspondence: ; Tel.: +33-499-63-60-48
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