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Zhang X, Shi T, Li J, Wu X, Wu K, Li D, Wang D, Guan J, Wang H. Natural History of KCNQ4 p.G285S Related Hearing Loss, Construction of iPSC and Mouse Model. Laryngoscope 2024; 134:2356-2363. [PMID: 37962101 DOI: 10.1002/lary.31179] [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: 01/25/2023] [Revised: 10/07/2023] [Accepted: 10/17/2023] [Indexed: 11/15/2023]
Abstract
OBJECTIVE KCNQ4 is one of the most common disease-causing genes involved in autosomal dominant non-syndromic hearing loss. We previously found that patients with KCNQ4 p.G285S exhibited a much more rapid deterioration in hearing loss than those with other KCNQ4 variants. To determine the rate of hearing loss and assess the disease for further analysis, we performed a long-term follow-up of these patients and generated patient-derived induced pluripotent stem cells (iPSCs), and a mouse model. METHODS Patients with KCNQ4 p.G285S from a five-generation family with hearing loss were followed up from 2005 to 2022. iPSCs were generated by stimulating peripheral blood mononuclear cells from the proband, and their pluripotency was determined. The Kcnq4 p.G286S mouse model was generated using CRISPR/Cas9, and its genotype and phenotype were identified. RESULTS (1) The annual rates of hearing loss at the frequencies of speech were 0.96 dB for the proband and 0.87 dB for his father during the follow-up period, which were faster than patients with other KCNQ4 variants. (2) The patient-derived iPSC line carrying KCNQ4 p.G285S, possessed the capacity of differentiation and pluripotency capacities. (3) Mutant mice with Kcnq4 p.G286S exhibited hearing loss and outer hair cell loss at 1 month of age. CONCLUSION Patients with KCNQ4 p.G285S variant exhibited significantly accelerated progression of hearing loss compared to those with other reported variants. Awareness of the natural history of hearing loss associated with KCNQ4 p.G285S is beneficial for genetic counseling and prognosis. The generation of the iPSCs and mouse model can provide a valuable foundation for further in-depth analyses. LEVEL OF EVIDENCE 4 Laryngoscope, 134:2356-2363, 2024.
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Affiliation(s)
- Xiaolong Zhang
- Senior Department of Otolaryngology Head and Neck Surgery, The Sixth Medical Center of PLA General Hospital, Medical School of Chinese PLA, Beijing, China
| | - Tao Shi
- Senior Department of Otolaryngology Head and Neck Surgery, The Sixth Medical Center of PLA General Hospital, Medical School of Chinese PLA, Beijing, China
| | - Jin Li
- Senior Department of Otolaryngology Head and Neck Surgery, The Sixth Medical Center of PLA General Hospital, Medical School of Chinese PLA, Beijing, China
- National Clinical Research Center for Otolaryngologic Diseases, Chinese PLA General Hospital, Beijing, China
| | - Xiaonan Wu
- Senior Department of Otolaryngology Head and Neck Surgery, The Sixth Medical Center of PLA General Hospital, Medical School of Chinese PLA, Beijing, China
| | - Kaili Wu
- Senior Department of Otolaryngology Head and Neck Surgery, The Sixth Medical Center of PLA General Hospital, Medical School of Chinese PLA, Beijing, China
| | - Danyang Li
- Senior Department of Otolaryngology Head and Neck Surgery, The Sixth Medical Center of PLA General Hospital, Medical School of Chinese PLA, Beijing, China
| | - Dayong Wang
- Senior Department of Otolaryngology Head and Neck Surgery, The Sixth Medical Center of PLA General Hospital, Medical School of Chinese PLA, Beijing, China
- National Clinical Research Center for Otolaryngologic Diseases, Chinese PLA General Hospital, Beijing, China
| | - Jing Guan
- Senior Department of Otolaryngology Head and Neck Surgery, The Sixth Medical Center of PLA General Hospital, Medical School of Chinese PLA, Beijing, China
- National Clinical Research Center for Otolaryngologic Diseases, Chinese PLA General Hospital, Beijing, China
| | - Hongyang Wang
- Senior Department of Otolaryngology Head and Neck Surgery, The Sixth Medical Center of PLA General Hospital, Medical School of Chinese PLA, Beijing, China
- National Clinical Research Center for Otolaryngologic Diseases, Chinese PLA General Hospital, Beijing, China
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Wang S, Li M, Liu P, Dong Y, Geng R, Zheng T, Zheng Q, Li B, Ma P. Col1a1 mediates the focal adhesion pathway affecting hearing in miR-29a mouse model by RNA-seq analysis. Exp Gerontol 2024; 185:112349. [PMID: 38103809 DOI: 10.1016/j.exger.2023.112349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 11/29/2023] [Accepted: 12/13/2023] [Indexed: 12/19/2023]
Abstract
Age-related hearing loss (ARHL) is a common neurodegenerative disease. Its molecular mechanisms have not been fully elucidated. In the present study, we obtained differential mRNA expression in the cochlea of 2-month-old miR-29a+/+ mice and miR-29a-/- mice by RNA-seq. Gene ontology (GO) analysis was used to identify molecular functions associated with hearing in miR-29a-/- mice, including being actin binding (GO: 0003779) and immune processes. We focused on the intersection of differential genes, miR-29a target genes and the sensory perception of sound (GO:0007605) genes, with six mRNA at this intersection, and we selected Col1a1 as our target gene. We validated Col1a1 as the direct target of miR-29a by molecular and cellular experiments. Total 6 pathways involved in Col1a1 were identified by through Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. We selected the focal adhesion pathway as our target pathway based. Their expression levels in miR-29a-/- mice were verified by qRT-PCR and Western blot. Compared with miR-29a+/+ mice, the expression levels of Col1a1, Itga4, Itga2, Itgb3, Itgb7, Pik3r3 and Ptk2 were different in miR-29a-/- mice. Immunofluorescence was used to locate genes in the cochlea. Col1a1, Itga4 and Itgb3 were differentially expressed in the basilar membranes and stria vascularis and spiral ganglion neurons compared to miR-29a+/+ mice. Pik3r3 and Ptk2 were differentially expressed in the basilar membranes and stria vascularis, but not at the s spiral ganglion neurons compared to miR-29a+/+ mice. Our results show that when miR-29a is knocked out, the Col1a1 mediates the focal adhesion pathway may affect the hearing of miR-29a-/- mice. These findings may provide a new direction for effective treatment of age-related hearing loss.
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Affiliation(s)
- Shuli Wang
- Hearing and Speech Rehabilitation Institute, School of Special Education, Binzhou Medical University, Yantai, China
| | - Mulan Li
- Hearing and Speech Rehabilitation Institute, School of Special Education, Binzhou Medical University, Yantai, China
| | - Pengcheng Liu
- Hearing and Speech Rehabilitation Institute, School of Special Education, Binzhou Medical University, Yantai, China
| | - Yaning Dong
- Hearing and Speech Rehabilitation Institute, School of Special Education, Binzhou Medical University, Yantai, China
| | - Ruishuang Geng
- Hearing and Speech Rehabilitation Institute, School of Special Education, Binzhou Medical University, Yantai, China
| | - Tihua Zheng
- Hearing and Speech Rehabilitation Institute, School of Special Education, Binzhou Medical University, Yantai, China
| | - Qingyin Zheng
- Hearing and Speech Rehabilitation Institute, School of Special Education, Binzhou Medical University, Yantai, China
| | - Bo Li
- Hearing and Speech Rehabilitation Institute, School of Special Education, Binzhou Medical University, Yantai, China.
| | - Peng Ma
- Hearing and Speech Rehabilitation Institute, School of Special Education, Binzhou Medical University, Yantai, China; School of Basic Medicine, Binzhou Medical University, Yantai, China.
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Richard EM, Brun E, Korchagina J, Crouzier L, Affortit C, Alves S, Cazevieille C, Mausset-Bonnefont AL, Lenoir M, Puel JL, Maurice T, Thiry M, Wang J, Delprat B. Wfs1 E864K knock-in mice illuminate the fundamental role of Wfs1 in endocochlear potential production. Cell Death Dis 2023; 14:387. [PMID: 37386014 PMCID: PMC10310813 DOI: 10.1038/s41419-023-05912-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: 01/11/2023] [Revised: 06/08/2023] [Accepted: 06/20/2023] [Indexed: 07/01/2023]
Abstract
Wolfram syndrome (WS) is a rare neurodegenerative disorder encompassing diabetes mellitus, diabetes insipidus, optic atrophy, hearing loss (HL) as well as neurological disorders. None of the animal models of the pathology are presenting with an early onset HL, impeding the understanding of the role of Wolframin (WFS1), the protein responsible for WS, in the auditory pathway. We generated a knock-in mouse, the Wfs1E864K line, presenting a human mutation leading to severe deafness in affected individuals. The homozygous mice showed a profound post-natal HL and vestibular syndrome, a collapse of the endocochlear potential (EP) and a devastating alteration of the stria vascularis and neurosensory epithelium. The mutant protein prevented the localization to the cell surface of the Na+/K+ATPase β1 subunit, a key protein for the maintenance of the EP. Overall, our data support a key role of WFS1 in the maintenance of the EP and the stria vascularis, via its binding partner, the Na+/K+ATPase β1 subunit.
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Affiliation(s)
| | - Emilie Brun
- INM, Univ Montpellier, INSERM, Montpellier, France
| | | | - Lucie Crouzier
- MMDN, Univ Montpellier, EPHE, INSERM, Montpellier, France
| | | | - Stacy Alves
- MMDN, Univ Montpellier, EPHE, INSERM, Montpellier, France
| | | | | | - Marc Lenoir
- INM, Univ Montpellier, INSERM, Montpellier, France
| | | | - Tangui Maurice
- MMDN, Univ Montpellier, EPHE, INSERM, Montpellier, France
| | - Marc Thiry
- Laboratoire de Biologie Cellulaire, Université de Liège, Liège, Belgique
| | - Jing Wang
- INM, Univ Montpellier, INSERM, Montpellier, France
| | - Benjamin Delprat
- MMDN, Univ Montpellier, EPHE, INSERM, Montpellier, France.
- INM, Univ Montpellier, INSERM, Montpellier, France.
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Oh KS, Roh JW, Joo SY, Ryu K, Kim JA, Kim SJ, Jang SH, Koh YI, Kim DH, Kim HY, Choi M, Jung J, Namkung W, Nam JH, Choi JY, Gee HY. Overlooked KCNQ4 variants augment the risk of hearing loss. Exp Mol Med 2023; 55:844-859. [PMID: 37009795 PMCID: PMC10167218 DOI: 10.1038/s12276-023-00976-4] [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: 08/16/2022] [Revised: 11/28/2022] [Accepted: 01/17/2023] [Indexed: 04/04/2023] Open
Abstract
Pathogenic variants of KCNQ4 cause symmetrical, late-onset, progressive, high-frequency-affected hearing loss, which eventually involves all frequencies with age. To understand the contribution of KCNQ4 variants to hearing loss, we analyzed whole-exome and genome sequencing data from patients with hearing loss and individuals whose hearing phenotypes were unknown. In KCNQ4, we identified seven missense variants and one deletion variant in 9 hearing loss patients and 14 missense variants in the Korean population with an unknown hearing loss phenotype. The p.R420W and p.R447W variants were found in both cohorts. To investigate the effects of these variants on KCNQ4 function, we performed whole-cell patch clamping and examined their expression levels. Except for p.G435Afs*61, all KCNQ4 variants exhibited normal expression patterns similar to those of wild-type KCNQ4. The p.R331Q, p.R331W, p.G435Afs*61, and p.S691G variants, which were identified in patients with hearing loss, showed a potassium (K+) current density lower than or similar to that of p.L47P, a previously reported pathogenic variant. The p.S185W and p.R216H variants shifted the activation voltage to hyperpolarized voltages. The channel activity of the p.S185W, p.R216H, p.V672M, and p.S691G KCNQ4 proteins was rescued by the KCNQ activators retigabine or zinc pyrithione, whereas p.G435Afs*61 KCNQ4 proteins were partially rescued by sodium butyrate, a chemical chaperone. Additionally, the structure of the variants predicted using AlphaFold2 showed impaired pore configurations, as did the patch-clamp data. Our findings suggest that KCNQ4 variants may be overlooked in hearing loss that starts in adulthood. Some of these variants are medically treatable; hence, genetic screening for KCNQ4 is important.
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Affiliation(s)
- Kyung Seok Oh
- Department of Pharmacology, Graduate School of Medical Science, Yonsei University College of Medicine, Brain Korea 21 Project, Seoul, 03722, Republic of Korea
| | - Jae Won Roh
- Department of Pharmacology, Graduate School of Medical Science, Yonsei University College of Medicine, Brain Korea 21 Project, Seoul, 03722, Republic of Korea
| | - Sun Young Joo
- Department of Pharmacology, Graduate School of Medical Science, Yonsei University College of Medicine, Brain Korea 21 Project, Seoul, 03722, Republic of Korea
| | - Kunhi Ryu
- Yonsei University College of Pharmacy, Incheon, 21983, Republic of Korea
| | - Jung Ah Kim
- Department of Pharmacology, Graduate School of Medical Science, Yonsei University College of Medicine, Brain Korea 21 Project, Seoul, 03722, Republic of Korea
| | - Se Jin Kim
- Department of Pharmacology, Graduate School of Medical Science, Yonsei University College of Medicine, Brain Korea 21 Project, Seoul, 03722, Republic of Korea
| | - Seung Hyun Jang
- Department of Pharmacology, Graduate School of Medical Science, Yonsei University College of Medicine, Brain Korea 21 Project, Seoul, 03722, Republic of Korea
| | - Young Ik Koh
- Department of Pharmacology, Graduate School of Medical Science, Yonsei University College of Medicine, Brain Korea 21 Project, Seoul, 03722, Republic of Korea
| | - Da Hye Kim
- Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Hye-Youn Kim
- Department of Pharmacology, Graduate School of Medical Science, Yonsei University College of Medicine, Brain Korea 21 Project, Seoul, 03722, Republic of Korea
| | - Murim Choi
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea
| | - Jinsei Jung
- Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Wan Namkung
- Yonsei University College of Pharmacy, Incheon, 21983, Republic of Korea
| | - Joo Hyun Nam
- Department of Physiology, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea.
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, Gyeonggi-do, 10326, Republic of Korea.
| | - Jae Young Choi
- Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.
| | - Heon Yung Gee
- Department of Pharmacology, Graduate School of Medical Science, Yonsei University College of Medicine, Brain Korea 21 Project, Seoul, 03722, Republic of Korea.
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Chou CW, Hsu YC. Current development of patient-specific induced pluripotent stem cells harbouring mitochondrial gene mutations and their applications in the treatment of sensorineural hearing loss. Hear Res 2023; 429:108689. [PMID: 36649664 DOI: 10.1016/j.heares.2023.108689] [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: 03/01/2022] [Revised: 12/30/2022] [Accepted: 01/03/2023] [Indexed: 01/06/2023]
Abstract
Of all the human body's sensory systems, the auditory system is perhaps its most intricate. Hearing loss can result from even modest damage or cell death in the inner ear, and is the most common form of sensory loss. Human hearing is made possible by the sensory epithelium, the lateral wall, and auditory nerves. The most prominent functional cells in the sensory epithelium are outer hair cells (OHCs), inner hair cells (IHCs), and supporting cells. Different sound frequencies are processed by OHCs and IHCs in different cochlear regions, with those in the apex responsible for low frequencies and those in the basal region responsible for high frequencies. Hair cells can be damaged or destroyed by loud noise, aging process, genetic mutations, ototoxicity, infection, and illness. As such, they are a primary target for treating sensorineural hearing loss. Other areas known to affect hearing include spiral ganglion neurons (SGNs) in the auditory nerve. Age-related degradation of HCs and SGNs can also cause hearing loss. The aim of this review is to introduce the roles of mitochondria in human auditory system and the inner ear's main cell types and cellular functions, before going on to detail the likely health benefits of iPSC technology. We posit that patient-specific iPSCs with mitochondrial gene mutations will be an important aspect of regenerative medicine and will lead to significant progress in the treatment of SNHL.
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Affiliation(s)
- Chao-Wen Chou
- Department of Audiology and Speech-Language Pathology, Mackay Medical College, New Taipei City, Taiwan
| | - Yi-Chao Hsu
- Department of Audiology and Speech-Language Pathology, Mackay Medical College, New Taipei City, Taiwan; Institute of Biomedical Sciences, Mackay Medical College, New Taipei City, Taiwan
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6
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Maamrah B, Pocsai K, Bayasgalan T, Csemer A, Pál B. KCNQ4 potassium channel subunit deletion leads to exaggerated acoustic startle reflex in mice. Neuroreport 2023; 34:232-237. [PMID: 36789839 PMCID: PMC10399928 DOI: 10.1097/wnr.0000000000001883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 01/06/2023] [Indexed: 02/16/2023]
Abstract
The potassium voltage-gated channel subfamily Q member 4 (KCNQ4) subunit forms channels responsible for M-current, a muscarine-sensitive potassium current regulating neuronal excitability. In contrast to other KCNQ subunits, its expression is restricted to the cochlear outer hair cells, the auditory brainstem and other brainstem nuclei in a great overlap with structures involved in startle reflex. We aimed to show whether startle reflexis affected by the loss of KCNQ4 subunit and whether these alterations are similar to the ones caused by brainstem hyperexcitability. Young adult KCNQ4 knockout mice and wild-type littermates, as well as mice expressing hM3D chemogenetic actuator in the pontine caudal nucleus and neurons innervating it were used for testing acoustic startle. The acoustic startle reflex was significantly increased in knockout mice compared with wild-type littermates. When mice expressing human M3 muscarinic (hM3D) in nuclei related to startle reflex were tested, a similar increase of the first acoustic startle amplitude and a strong habituation of the further responses was demonstrated. We found that the acoustic startle reflex is exaggerated and minimal habituation occurs in KCNQ4 knockout animals. These changes are distinct from the effects of the hyperexcitability of nuclei involved in startle. One can conclude that the exaggerated startle reflex found with the KCNQ4 subunit deletion is the consequence of both the cochlear damage and the changes in neuronal excitability of startle networks.
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Affiliation(s)
- Baneen Maamrah
- Department of Physiology, Faculty of Medicine, University of Debrecen
- Doctoral School of Molecular Medicine, University of Debrecen, Debrecen, Hungary
| | - Krisztina Pocsai
- Department of Physiology, Faculty of Medicine, University of Debrecen
| | - Tsogbadrakh Bayasgalan
- Department of Physiology, Faculty of Medicine, University of Debrecen
- Doctoral School of Molecular Medicine, University of Debrecen, Debrecen, Hungary
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, New Jersey, USA
| | - Andrea Csemer
- Department of Physiology, Faculty of Medicine, University of Debrecen
| | - Balázs Pál
- Department of Physiology, Faculty of Medicine, University of Debrecen
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Homma K. The Pathological Mechanisms of Hearing Loss Caused by KCNQ1 and KCNQ4 Variants. Biomedicines 2022; 10:biomedicines10092254. [PMID: 36140355 PMCID: PMC9496569 DOI: 10.3390/biomedicines10092254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/08/2022] [Accepted: 09/09/2022] [Indexed: 11/29/2022] Open
Abstract
Deafness-associated genes KCNQ1 (also associated with heart diseases) and KCNQ4 (only associated with hearing loss) encode the homotetrameric voltage-gated potassium ion channels Kv7.1 and Kv7.4, respectively. To date, over 700 KCNQ1 and over 70 KCNQ4 variants have been identified in patients. The vast majority of these variants are inherited dominantly, and their pathogenicity is often explained by dominant-negative inhibition or haploinsufficiency. Our recent study unexpectedly identified cell-death-inducing cytotoxicity in several Kv7.1 and Kv7.4 variants. Elucidation of this cytotoxicity mechanism and identification of its modifiers (drugs) have great potential for aiding the development of a novel pharmacological strategy against many pathogenic KCNQ variants. The purpose of this review is to disseminate this emerging pathological role of Kv7 variants and to underscore the importance of experimentally characterizing disease-associated variants.
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Affiliation(s)
- Kazuaki Homma
- Department of Otolaryngology-Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA; ; Tel.: +1-312-503-5344
- The Hugh Knowles Center for Clinical and Basic Science in Hearing and Its Disorders, Northwestern University, Evanston, IL 60608, USA
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Peixoto Pinheiro B, Müller M, Bös M, Guezguez J, Burnet M, Tornincasa M, Rizzetto R, Rolland JF, Liberati C, Lohmer S, Adel Y, Löwenheim H. A potassium channel agonist protects hearing function and promotes outer hair cell survival in a mouse model for age-related hearing loss. Cell Death Dis 2022; 13:595. [PMID: 35817766 PMCID: PMC9273644 DOI: 10.1038/s41419-022-04915-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 04/29/2022] [Accepted: 05/04/2022] [Indexed: 01/21/2023]
Abstract
Age-related hearing loss (ARHL) is the most common sensory impairment mainly caused by degeneration of sensory hair cells in the cochlea with no causal medical treatment available. Auditory function and sensory hair cell survival critically depend on the Kv7.4 (KCNQ4) channel, a voltage-gated potassium channel expressed in outer hair cells (OHCs), with its impaired function or reduced activity previously associated with ARHL. Here, we investigated the effect of a potent small-molecule Kv7.4 agonist on ARHL in the senescence-accelerated mouse prone 8 (SAMP8) model. For the first time in vivo, we show that Kv7.4 activation can significantly reduce age-related threshold shifts of auditory brainstem responses as well as OHC loss in the SAMP8 model. Pharmacological activation of Kv7.4 thus holds great potential as a therapeutic approach for ARHL as well as other hearing impairments related to Kv7.4 function.
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Affiliation(s)
- Barbara Peixoto Pinheiro
- grid.10392.390000 0001 2190 1447Translational Hearing Research, Tübingen Hearing Research Center, Department of Otolaryngology, Head & Neck Surgery, University of Tübingen, 72076 Tübingen, Germany
| | - Marcus Müller
- grid.10392.390000 0001 2190 1447Translational Hearing Research, Tübingen Hearing Research Center, Department of Otolaryngology, Head & Neck Surgery, University of Tübingen, 72076 Tübingen, Germany
| | - Michael Bös
- Acousia Therapeutics, 72070 Tübingen, Germany
| | | | | | - Mara Tornincasa
- grid.427692.c0000 0004 1794 5078Axxam, Bresso, 20091 Milan, Italy
| | | | | | - Chiara Liberati
- grid.427692.c0000 0004 1794 5078Axxam, Bresso, 20091 Milan, Italy
| | - Stefan Lohmer
- grid.427692.c0000 0004 1794 5078Axxam, Bresso, 20091 Milan, Italy
| | - Youssef Adel
- grid.10392.390000 0001 2190 1447Translational Hearing Research, Tübingen Hearing Research Center, Department of Otolaryngology, Head & Neck Surgery, University of Tübingen, 72076 Tübingen, Germany
| | - Hubert Löwenheim
- grid.10392.390000 0001 2190 1447Translational Hearing Research, Tübingen Hearing Research Center, Department of Otolaryngology, Head & Neck Surgery, University of Tübingen, 72076 Tübingen, Germany
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Blanc F, Bemelmans AP, Affortit C, Joséphine C, Puel JL, Mondain M, Wang J. A Single Cisterna Magna Injection of AAV Leads to Binaural Transduction in Mice. Front Cell Dev Biol 2022; 9:783504. [PMID: 35087833 PMCID: PMC8787364 DOI: 10.3389/fcell.2021.783504] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 12/13/2021] [Indexed: 11/13/2022] Open
Abstract
Viral-mediated gene augmentation, silencing, or editing offers tremendous promise for the treatment of inherited and acquired deafness. Inner-ear gene therapies often require a safe, clinically useable and effective route of administration to target both ears, while avoiding damage to the delicate structures of the inner ear. Here, we examined the possibility of using a cisterna magna injection as a new cochlear local route for initiating binaural transduction by different serotypes of the adeno-associated virus (AAV2/8, AAV2/9, AAV2/Anc80L65). The results were compared with those following canalostomy injection, one of the existing standard inner ear local delivery routes. Our results demonstrated that a single injection of AAVs enables high-efficiency binaural transduction of almost all inner hair cells with a basal-apical pattern and of large numbers of spiral ganglion neurons of the basal portion of the cochlea, without affecting auditory function and cochlear structures. Taken together, these results reveal the potential for using a cisterna magna injection as a local route for binaural gene therapy applications, but extensive testing will be required before translation beyond mouse models.
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Affiliation(s)
- Fabian Blanc
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, Montpellier, France.,CHRU Montpellier-Centre Hospitalier Régional Universitaire, Montpellier, France
| | - Alexis-Pierre Bemelmans
- Molecular Imaging Research Center, Institut de Biologie François Jacob, Direction de la Recherche Fondamentale, CEA, Fontenay-aux-Roses, France.,Université Paris-Saclay, CEA, CNRS, Laboratoire des Maladies Neurodégénératives, mécanismes, thérapies, imagerie, Fontenay-aux-Roses, France
| | - Corentin Affortit
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, Montpellier, France
| | - Charlène Joséphine
- Molecular Imaging Research Center, Institut de Biologie François Jacob, Direction de la Recherche Fondamentale, CEA, Fontenay-aux-Roses, France.,Université Paris-Saclay, CEA, CNRS, Laboratoire des Maladies Neurodégénératives, mécanismes, thérapies, imagerie, Fontenay-aux-Roses, France
| | - Jean-Luc Puel
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, Montpellier, France
| | - Michel Mondain
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, Montpellier, France.,CHRU Montpellier-Centre Hospitalier Régional Universitaire, Montpellier, France
| | - Jing Wang
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, Montpellier, France.,CHRU Montpellier-Centre Hospitalier Régional Universitaire, Montpellier, France
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Progression of KCNQ4 related genetic hearing loss: a narrative review. JOURNAL OF BIO-X RESEARCH 2021. [DOI: 10.1097/jbr.0000000000000112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Hu Z, Komal F, Singh A, Deng M. Generation of a Spiral Ganglion Neuron Degeneration Mouse Model. Front Cell Dev Biol 2021; 9:761847. [PMID: 34778272 PMCID: PMC8578993 DOI: 10.3389/fcell.2021.761847] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 09/29/2021] [Indexed: 11/27/2022] Open
Abstract
Spiral ganglion neurons (SGNs) can be injured by a wide variety of insults. However, there still is a lack of degeneration models to specifically damage the SGNs without disturbing other types of cells in the inner ear. This study aims to generate an SGN-specific damage model using the Cre-LoxP transgenic mouse strains. The Cre-inducible diphtheria toxin receptor (iDTR+/+) knock-in mouse strain was crossed with a mouse strain with Cre activity specific to neurons (NeflCreER/CreER). Expression of the Cre-recombinase activity was evaluated using the reporter mouse strain Ai9 at pre-hearing, hearing onset, and post-hearing stages. Accordingly, heterozygous NeflCreER/+;iDTR+/– mice were treated with tamoxifen on postnatal days 1–5 (P1–5), followed by diphtheria toxin (DT) or vehicle injection on P7, P14, and P21 to evaluate the SGN loss. Robust tamoxifen-induced Cre-mediated Ai9 tdTomato fluorescence was observed in the SGN area of heterozygous NeflCreER/+;Ai9+/– mice treated with tamoxifen, whereas vehicle-treated heterozygote mice did not show tdTomato fluorescence. Compared to vehicle-treated NeflCreER/+;iDTR+/– mice, DT-treated NeflCreER/+;iDTR+/– mice showed significant auditory brainstem response (ABR) threshold shifts and SGN cell loss. Hair cell count and functional study did not show significant changes. These results demonstrate that the NeflCreER/CreER mouse strain exhibits inducible SGN-specific Cre activity in the inner ear, which may serve as a valuable SGN damage model for regeneration research of the inner ear.
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Affiliation(s)
- Zhengqing Hu
- John D. Dingell VA Medical Center, Detroit, MI, United States.,Department of Otolaryngology-HNS, Wayne State University School of Medicine, Detroit, MI, United States
| | - Fnu Komal
- Department of Otolaryngology-HNS, Wayne State University School of Medicine, Detroit, MI, United States
| | - Aditi Singh
- Department of Otolaryngology-HNS, Wayne State University School of Medicine, Detroit, MI, United States
| | - Meng Deng
- Department of Otolaryngology-HNS, Wayne State University School of Medicine, Detroit, MI, United States
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12
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Kojima T, Wasano K, Takahashi S, Homma K. Cell death-inducing cytotoxicity in truncated KCNQ4 variants associated with DFNA2 hearing loss. Dis Model Mech 2021; 14:272416. [PMID: 34622280 PMCID: PMC8628632 DOI: 10.1242/dmm.049015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 09/22/2021] [Indexed: 01/30/2023] Open
Abstract
KCNQ4 encodes the homotetrameric voltage-dependent potassium ion channel Kv7.4, and is the causative gene for autosomal dominant nonsyndromic sensorineural hearing loss, DFNA2. Dominant-negative inhibition accounts for the observed dominant inheritance of many DFNA2-associated KCNQ4 variants. In addition, haploinsufficiency has been presumed as the pathological mechanism for truncated Kv7.4 variants lacking the C-terminal tetramerization region, as they are unlikely to exert a dominant-negative inhibitory effect. Such truncated Kv7.4 variants should result in relatively mild hearing loss when heterozygous; however, this is not always the case. In this study, we characterized Kv7.4Q71fs (c.211delC), Kv7.4W242X (c.725G>A) and Kv7.4A349fs (c.1044_1051del8) in heterologous expression systems and found that expression of these truncated Kv7.4 variants induced cell death. We also found similar cell death-inducing cytotoxic effects in truncated Kv7.1 (KCNQ1) variants, suggesting that the generality of our findings could account for the dominant inheritance of many, if not most, truncated Kv7 variants. Moreover, we found that the application of autophagy inducers can ameliorate the cytotoxicity, providing a novel insight for the development of alternative therapeutic strategies for Kv7.4 variants. Summary: Expression of truncated KCNQ4 variants lacking the C-terminal tetramerization domain results in cell-death inducing cytotoxicity, providing novel insight into the development of alternative therapeutic strategies for DFNA2 hearing loss.
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Affiliation(s)
- Takashi Kojima
- Department of Otolaryngology - Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.,Department of Otolaryngology, Head and Neck Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo 160-8582, Japan
| | - Koichiro Wasano
- Department of Otolaryngology - Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.,Laboratory of Auditory Disorders, Division of Hearing and Balance Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro, Tokyo 152-8902, Japan
| | - Satoe Takahashi
- Department of Otolaryngology - Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Kazuaki Homma
- Department of Otolaryngology - Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.,The Hugh Knowles Center for Clinical and Basic Science in Hearing and Its Disorders, Northwestern University, Evanston, IL 60608, USA
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13
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A KCNQ4 c.546C>G Genetic Variant Associated with Late Onset Non-Syndromic Hearing Loss in a Taiwanese Population. Genes (Basel) 2021; 12:genes12111711. [PMID: 34828318 PMCID: PMC8618107 DOI: 10.3390/genes12111711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 10/18/2021] [Accepted: 10/26/2021] [Indexed: 11/19/2022] Open
Abstract
Clinical presentation is heterogeneous for autosomal dominant nonsyndromic hearing loss (ADNSHL). Variants of KCNQ4 gene is a common genetic factor of ADNSHL. Few studies have investigated the association between hearing impairment and the variant c.546C>G of KCNQ4. Here, we investigated the phenotype and clinical manifestations of the KCNQ4 variant. Study subjects were selected from the participants of the Taiwan Precision Medicine Initiative. In total, we enrolled 12 individuals with KCNQ4 c.546C>G carriers and 107 non-carriers, and performed pure tone audiometry (PTA) test and phenome-wide association (PheWAS) analysis for the patients. We found that c.546C>G variant was related to an increased risk of hearing loss. All patients with c.546C>G variant were aged >65 years and had sensorineural and high frequency hearing loss. Of these patients, a third (66.7%) showed moderate and progressive hearing loss, 41.7% complained of tinnitus and 16.7% complained of vertigo. Additionally, we found a significant association between KCNQ4 c.546C>G variant, aortic aneurysm, fracture of lower limb and polyneuropathy in diabetes. KCNQ4 c.546C>G is likely a potentially pathogenic variant of ADNSHL in the elderly population. Genetic counseling, annual audiogram and early assistive listening device intervention are highly recommended to prevent profound hearing impairment in this patient group.
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14
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Peixoto Pinheiro B, Adel Y, Knipper M, Müller M, Löwenheim H. Auditory Threshold Variability in the SAMP8 Mouse Model of Age-Related Hearing Loss: Functional Loss and Phenotypic Change Precede Outer Hair Cell Loss. Front Aging Neurosci 2021; 13:708190. [PMID: 34408646 PMCID: PMC8366269 DOI: 10.3389/fnagi.2021.708190] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 07/09/2021] [Indexed: 11/13/2022] Open
Abstract
Age-related hearing loss (ARHL) is the most common sensory deficit in aging society, which is accompanied by increased speech discrimination difficulties in noisy environments, social isolation, and cognitive decline. The audiometric degree of ARHL is largely correlated with sensory hair cell loss in addition to age-related factors not captured by histopathological analysis of the human cochlea. Previous studies have identified the senescence-accelerated mouse prone strain 8 (SAMP8) as a model for studying ARHL and age-related modifications of the cochlear redox environment. However, the SAMP8 population exhibits a large variability in auditory function decline over age, whose underlying cause remains unknown. In this study, we analyzed auditory function of SAMP8 mice by measuring auditory brainstem response (ABR) thresholds at the age of 6 weeks (juvenile), 12 weeks (young adult), and 24 weeks (adult). Consistent with previous studies, SAMP8 mice exhibit an early progressive, age-related decline of hearing acuity. However, a spatiotemporal cytohistological analysis showed that the significant increase in threshold variability was not concurrently reflected in outer hair cell (OHC) loss observed in the lower and upper quartiles of the ABR threshold distributions over age. This functional loss was found to precede OHC loss suggesting that age-related phenotypic changes may be contributing factors not represented in cytohistological analysis. The expression of potassium channels KCNQ4 (KV7.4), which mediates the current IK,n crucial for the maintenance of OHC membrane potential, and KCNQ1 (KV7.1), which is an essential component in potassium circulation and secretion into the endolymph generating the endocochlear potential, showed differences between these quartiles and age groups. This suggests that phenotypic changes in OHCs or the stria vascularis due to variable oxidative deficiencies in individual mice may be predictors of the observed threshold variability in SAMP8 mice and their progressive ARHL. In future studies, further phenotypic predictors affected by accumulated metabolic challenges over age need to be investigated as potentially underlying causes of ARHL preceding irreversible OHC loss in the SAMP8 mouse model.
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Affiliation(s)
- Barbara Peixoto Pinheiro
- Translational Hearing Research, Tübingen Hearing Research Center, Department of Otolaryngology, Head and Neck Surgery, University of Tübingen, Tübingen, Germany
| | - Youssef Adel
- Translational Hearing Research, Tübingen Hearing Research Center, Department of Otolaryngology, Head and Neck Surgery, University of Tübingen, Tübingen, Germany
| | - Marlies Knipper
- Molecular Physiology of Hearing, Tübingen Hearing Research Center, Department of Otolaryngology, Head and Neck Surgery, University of Tübingen, Tübingen, Germany
| | - Marcus Müller
- Translational Hearing Research, Tübingen Hearing Research Center, Department of Otolaryngology, Head and Neck Surgery, University of Tübingen, Tübingen, Germany
| | - Hubert Löwenheim
- Translational Hearing Research, Tübingen Hearing Research Center, Department of Otolaryngology, Head and Neck Surgery, University of Tübingen, Tübingen, Germany
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15
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Bayasgalan T, Stupniki S, Kovács A, Csemer A, Szentesi P, Pocsai K, Dionisio L, Spitzmaul G, Pál B. Alteration of Mesopontine Cholinergic Function by the Lack of KCNQ4 Subunit. Front Cell Neurosci 2021; 15:707789. [PMID: 34381336 PMCID: PMC8352570 DOI: 10.3389/fncel.2021.707789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 06/28/2021] [Indexed: 11/16/2022] Open
Abstract
The pedunculopontine nucleus (PPN), a structure known as a cholinergic member of the reticular activating system (RAS), is source and target of cholinergic neuromodulation and contributes to the regulation of the sleep–wakefulness cycle. The M-current is a voltage-gated potassium current modulated mainly by cholinergic signaling. KCNQ subunits ensemble into ion channels responsible for the M-current. In the central nervous system, KCNQ4 expression is restricted to certain brainstem structures such as the RAS nuclei. Here, we investigated the presence and functional significance of KCNQ4 in the PPN by behavioral studies and the gene and protein expressions and slice electrophysiology using a mouse model lacking KCNQ4 expression. We found that this mouse has alterations in the adaptation to changes in light–darkness cycles, representing the potential role of KCNQ4 in the regulation of the sleep–wakefulness cycle. As cholinergic neurons from the PPN participate in the regulation of this cycle, we investigated whether the cholinergic PPN might also possess functional KCNQ4 subunits. Although the M-current is an electrophysiological hallmark of cholinergic neurons, only a subpopulation of them had KCNQ4-dependent M-current. Interestingly, the absence of the KCNQ4 subunit altered the expression patterns of the other KCNQ subunits in the PPN. We also determined that, in wild-type animals, the cholinergic inputs of the PPN modulated the M-current, and these in turn can modulate the level of synchronization between neighboring PPN neurons. Taken together, the KCNQ4 subunit is present in a subpopulation of PPN cholinergic neurons, and it may contribute to the regulation of the sleep–wakefulness cycle.
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Affiliation(s)
- T Bayasgalan
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - S Stupniki
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional Del Sur (UNS), Bahía Blanca, Argentina.,Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Bahía Blanca, Argentina
| | - A Kovács
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - A Csemer
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - P Szentesi
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - K Pocsai
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - L Dionisio
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional Del Sur (UNS), Bahía Blanca, Argentina.,Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Bahía Blanca, Argentina
| | - G Spitzmaul
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional Del Sur (UNS), Bahía Blanca, Argentina.,Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Bahía Blanca, Argentina
| | - B Pál
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
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16
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Activation of KCNQ4 as a Therapeutic Strategy to Treat Hearing Loss. Int J Mol Sci 2021; 22:ijms22052510. [PMID: 33801540 PMCID: PMC7958948 DOI: 10.3390/ijms22052510] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/16/2021] [Accepted: 02/22/2021] [Indexed: 12/14/2022] Open
Abstract
Potassium voltage-gated channel subfamily q member 4 (KCNQ4) is a voltage-gated potassium channel that plays essential roles in maintaining ion homeostasis and regulating hair cell membrane potential. Reduction of the activity of the KCNQ4 channel owing to genetic mutations is responsible for nonsyndromic hearing loss, a typically late-onset, initially high-frequency loss progressing over time. In addition, variants of KCNQ4 have also been associated with noise-induced hearing loss and age-related hearing loss. Therefore, the discovery of small compounds activating or potentiating KCNQ4 is an important strategy for the curative treatment of hearing loss. In this review, we updated the current concept of the physiological role of KCNQ4 in the inner ear and the pathologic mechanism underlying the role of KCNQ4 variants with regard to hearing loss. Finally, we focused on currently developed KCNQ4 activators and their pros and cons, paving the way for the future development of specific KCNQ4 activators as a remedy for hearing loss.
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17
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Abstract
Kv7.1-Kv7.5 (KCNQ1-5) K+ channels are voltage-gated K+ channels with major roles in neurons, muscle cells and epithelia where they underlie physiologically important K+ currents, such as neuronal M current and cardiac IKs. Specific biophysical properties of Kv7 channels make them particularly well placed to control the activity of excitable cells. Indeed, these channels often work as 'excitability breaks' and are targeted by various hormones and modulators to regulate cellular activity outputs. Genetic deficiencies in all five KCNQ genes result in human excitability disorders, including epilepsy, arrhythmias, deafness and some others. Not surprisingly, this channel family attracts considerable attention as potential drug targets. Here we will review biophysical properties and tissue expression profile of Kv7 channels, discuss recent advances in the understanding of their structure as well as their role in various neurological, cardiovascular and other diseases and pathologies. We will also consider a scope for therapeutic targeting of Kv7 channels for treatment of the above health conditions.
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18
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Age-related hearing loss pertaining to potassium ion channels in the cochlea and auditory pathway. Pflugers Arch 2020; 473:823-840. [PMID: 33336302 PMCID: PMC8076138 DOI: 10.1007/s00424-020-02496-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 10/27/2020] [Accepted: 11/10/2020] [Indexed: 12/12/2022]
Abstract
Age-related hearing loss (ARHL) is the most prevalent sensory deficit in the elderly and constitutes the third highest risk factor for dementia. Lifetime noise exposure, genetic predispositions for degeneration, and metabolic stress are assumed to be the major causes of ARHL. Both noise-induced and hereditary progressive hearing have been linked to decreased cell surface expression and impaired conductance of the potassium ion channel KV7.4 (KCNQ4) in outer hair cells, inspiring future therapies to maintain or prevent the decline of potassium ion channel surface expression to reduce ARHL. In concert with KV7.4 in outer hair cells, KV7.1 (KCNQ1) in the stria vascularis, calcium-activated potassium channels BK (KCNMA1) and SK2 (KCNN2) in hair cells and efferent fiber synapses, and KV3.1 (KCNC1) in the spiral ganglia and ascending auditory circuits share an upregulated expression or subcellular targeting during final differentiation at hearing onset. They also share a distinctive fragility for noise exposure and age-dependent shortfalls in energy supply required for sustained surface expression. Here, we review and discuss the possible contribution of select potassium ion channels in the cochlea and auditory pathway to ARHL. We postulate genes, proteins, or modulators that contribute to sustained ion currents or proper surface expressions of potassium channels under challenging conditions as key for future therapies of ARHL.
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