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Chen J, Lewis MA, Wai A, Yin L, Dawson SJ, Ingham NJ, Steel KP. A new mutation of Sgms1 causes gradual hearing loss associated with a reduced endocochlear potential. Hear Res 2024; 451:109091. [PMID: 39067415 DOI: 10.1016/j.heares.2024.109091] [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: 04/25/2024] [Revised: 07/04/2024] [Accepted: 07/22/2024] [Indexed: 07/30/2024]
Abstract
Sgms1 encodes sphingomyelin synthase 1, an enzyme in the sphingosine-1-phosphate signalling pathway, and was previously reported to underlie hearing impairment in the mouse. A new mouse allele, Sgms1tm1a, unexpectedly showed normal Auditory Brainstem Response thresholds. We found that the Sgms1tm1a mutation led to incomplete knockdown of transcript to 20 % of normal values, which was enough to support normal hearing. The Sgms1tm1b allele was generated by knocking out exon 7, leading to a complete lack of detectable transcript in the inner ear. Sgms1tm1b homozygotes showed largely normal auditory brainstem response thresholds at first, followed by progressive loss of sensitivity until they showed severe impairment at 6 months old. The endocochlear potential was consistently reduced in Sgms1tm1b mutants at 3, 4 and 8 weeks old, to around 80 mV compared with around 120 mV in control littermates. The stria vascularis showed a characteristic irregularity of marginal cell surfaces and patchy loss of Kcnq1 expression at their apical membrane, and expression analysis of the lateral wall suggested that marginal cells were the most likely initial site of dysfunction in the mutants. Finally, significant association of auditory thresholds with DNA markers within and close to the human SGMS1 gene were found in the 1958 Birth Cohort, suggesting that SGMS1 variants may play a role in the range of hearing abilities in the human population.
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Affiliation(s)
- Jing Chen
- Wolfson Sensory, Pain and Regeneration Centre, King's College London, London SE1 1UL, United Kingdom
| | - Morag A Lewis
- Wolfson Sensory, Pain and Regeneration Centre, King's College London, London SE1 1UL, United Kingdom
| | - Alisa Wai
- Wolfson Sensory, Pain and Regeneration Centre, King's College London, London SE1 1UL, United Kingdom
| | - Lucia Yin
- Wolfson Sensory, Pain and Regeneration Centre, King's College London, London SE1 1UL, United Kingdom
| | - Sally J Dawson
- UCL Ear Institute, University College London, London WC1X 8EE, United Kingdom
| | - Neil J Ingham
- Wolfson Sensory, Pain and Regeneration Centre, King's College London, London SE1 1UL, United Kingdom
| | - Karen P Steel
- Wolfson Sensory, Pain and Regeneration Centre, King's College London, London SE1 1UL, United Kingdom.
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2
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Maniaci A, La Via L, Lechien JR, Sangiorgio G, Iannella G, Magliulo G, Pace A, Mat Q, Lavalle S, Lentini M. Hearing Loss and Oxidative Stress: A Comprehensive Review. Antioxidants (Basel) 2024; 13:842. [PMID: 39061910 PMCID: PMC11274311 DOI: 10.3390/antiox13070842] [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: 06/11/2024] [Revised: 07/05/2024] [Accepted: 07/11/2024] [Indexed: 07/28/2024] Open
Abstract
Hearing loss is a prevalent condition affecting millions of people worldwide. Hearing loss has been linked to oxidative stress as a major factor in its onset and progression. The goal of this thorough analysis is to investigate the connection between oxidative stress and hearing loss, with an emphasis on the underlying mechanisms and possible treatments. The review addressed the many forms of hearing loss, the role of reactive oxygen species (ROS) in causing damage to the cochlea, and the auditory system's antioxidant defensive mechanisms. The review also goes over the available data that support the use of antioxidants and other methods to lessen hearing loss brought on by oxidative stress. We found that oxidative stress is implicated in multiple types of hearing loss, including age-related, noise-induced, and ototoxic hearing impairment. The cochlea's unique anatomical and physiological characteristics, such as high metabolic activity and limited blood supply, make it particularly susceptible to oxidative damage. Antioxidant therapies have shown promising results in both animal models and clinical studies for preventing and mitigating hearing loss. Emerging therapeutic approaches, including targeted drug delivery systems and gene therapy, offer new possibilities for addressing oxidative stress in the auditory system. The significance of this review lies in its comprehensive analysis of the intricate relationship between oxidative stress and hearing loss. By synthesizing current knowledge and identifying gaps in understanding, this review provides valuable insights for both researchers and clinicians. It highlights the potential of antioxidant-based interventions and emphasizes the need for further research into personalized treatment strategies. Our findings on oxidative stress mechanisms may also affect clinical practice and future research directions. This review serves as a foundation for developing novel therapeutic approaches and may inform evidence-based strategies for the prevention and treatment of hearing loss, ultimately contributing to improved quality of life for millions affected by this condition worldwide.
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Affiliation(s)
- A. Maniaci
- Faculty of Medicine and Surgery, University of Enna Kore, 94100 Enna, Italy;
- ASP Ragusa-Hospital Giovanni Paolo II, 97100 Ragusa, Italy;
- Otology Study Group, Young Otolaryngologists-International Federation of Otorhinolaryngological Societies, 13005 Paris, France; (J.R.L.); (G.I.); (A.P.); (Q.M.)
| | - L. La Via
- Department of Anaesthesia and Intensive Care, University Hospital Policlinico-San Marco, 95125 Catania, Italy
| | - J. R. Lechien
- Otology Study Group, Young Otolaryngologists-International Federation of Otorhinolaryngological Societies, 13005 Paris, France; (J.R.L.); (G.I.); (A.P.); (Q.M.)
- Department of Human Anatomy and Experimental Oncology, Faculty of Medicine, UMONS Research Institute for Health Sciences and Technology, University of Mons (UMons), 7000 Mons, Belgium
- Department of Otolaryngology-Head & Neck Surgery, Foch Hospital, School of Medicine, UFR Simone Veil, Université Versailles Saint-Quentin-en-Yvelines (Paris Saclay University), 78180 Paris, France
- Department of Otolaryngology-Head & Neck Surgery, EpiCURA Hospital, 7301 Hornu, Belgium
| | - G. Sangiorgio
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy;
| | - G. Iannella
- Otology Study Group, Young Otolaryngologists-International Federation of Otorhinolaryngological Societies, 13005 Paris, France; (J.R.L.); (G.I.); (A.P.); (Q.M.)
- Department of ‘Organi di Senso’, University “Sapienza”, 00185 Rome, Italy;
| | - G. Magliulo
- Department of ‘Organi di Senso’, University “Sapienza”, 00185 Rome, Italy;
| | - A. Pace
- Otology Study Group, Young Otolaryngologists-International Federation of Otorhinolaryngological Societies, 13005 Paris, France; (J.R.L.); (G.I.); (A.P.); (Q.M.)
- Department of ‘Organi di Senso’, University “Sapienza”, 00185 Rome, Italy;
| | - Q. Mat
- Otology Study Group, Young Otolaryngologists-International Federation of Otorhinolaryngological Societies, 13005 Paris, France; (J.R.L.); (G.I.); (A.P.); (Q.M.)
- Department of Otorhinolaryngology, C.H.U. Charleroi, Chaussée de Bruxelles 140, 6042 Charleroi, Belgium
| | - S. Lavalle
- Faculty of Medicine and Surgery, University of Enna Kore, 94100 Enna, Italy;
| | - M. Lentini
- ASP Ragusa-Hospital Giovanni Paolo II, 97100 Ragusa, Italy;
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Hong H, Koo EJ, Park Y, Song G, Joo SY, Kim JA, Gee HY, Jung J, Park K, Han GC, Choie JY, Kim SH. Vestibular hair cells are more prone to damage by excessive acceleration insult in the mouse with KCNQ4 dysfunction. Sci Rep 2024; 14:15260. [PMID: 38956136 PMCID: PMC11219875 DOI: 10.1038/s41598-024-66115-9] [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: 11/17/2023] [Accepted: 06/27/2024] [Indexed: 07/04/2024] Open
Abstract
KCNQ4 is a voltage-gated K+ channel was reported to distribute over the basolateral surface of type 1 vestibular hair cell and/or inner surface of calyx and heminode of the vestibular nerve connected to the type 1 vestibular hair cells of the inner ear. However, the precise localization of KCNQ4 is still controversial and little is known about the vestibular phenotypes caused by KCNQ4 dysfunction or the specific role of KCNQ4 in the vestibular organs. To investigate the role of KCNQ4 in the vestibular organ, 6-g hypergravity stimulation for 24 h, which represents excessive mechanical stimulation of the sensory epithelium, was applied to p.W277S Kcnq4 transgenic mice. KCNQ4 was detected on the inner surface of calyx of the vestibular afferent in transmission electron microscope images with immunogold labelling. Vestibular function decrease was more severe in the Kcnq4p.W277S/p.W277S mice than in the Kcnq4+/+ and Kcnq4+/p.W277S mice after the stimulation. The vestibular function loss was resulted from the loss of type 1 vestibular hair cells, which was possibly caused by increased depolarization duration. Retigabine, a KCNQ activator, prevented hypergravity-induced vestibular dysfunction and hair cell loss. Patients with KCNQ4 mutations also showed abnormal clinical vestibular function tests. These findings suggest that KCNQ4 plays an essential role in calyx and afferent of type 1 vestibular hair cell preserving vestibular function against excessive mechanical stimulation.
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Affiliation(s)
- Hansol Hong
- Department of Otorhinolaryngology, Won-Sang Lee Institute for Hearing Loss, Yonsei University College of Medicine and Graduate School of Medicine, Seoul, Republic of Korea
| | - Eun Ji Koo
- Department of Otorhinolaryngology, Gachon University College of Medicine, Incheon, Republic of Korea
| | - Yesai Park
- Department of Otorhinolaryngology, Incheon St. Mary's Hospital, Catholic University College of Medicine, Incheon, Republic of Korea
| | - Gabae Song
- Department of Otorhinolaryngology, Won-Sang Lee Institute for Hearing Loss, Yonsei University College of Medicine and Graduate School of Medicine, Seoul, Republic of Korea
| | - Sun Young Joo
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jung Ah Kim
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Heon Yung Gee
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jinsei Jung
- Department of Otorhinolaryngology, Won-Sang Lee Institute for Hearing Loss, Yonsei University College of Medicine and Graduate School of Medicine, Seoul, Republic of Korea
| | - Kangyoon Park
- Department of Otorhinolaryngology, Won-Sang Lee Institute for Hearing Loss, Yonsei University College of Medicine and Graduate School of Medicine, Seoul, Republic of Korea
| | - Gyu Cheol Han
- Department of Otorhinolaryngology, Gachon University College of Medicine, Incheon, Republic of Korea.
| | - Jae Young Choie
- Department of Otorhinolaryngology, Won-Sang Lee Institute for Hearing Loss, Yonsei University College of Medicine and Graduate School of Medicine, Seoul, Republic of Korea.
| | - Sung Huhn Kim
- Department of Otorhinolaryngology, Won-Sang Lee Institute for Hearing Loss, Yonsei University College of Medicine and Graduate School of Medicine, Seoul, Republic of Korea.
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He C, Gai H, Zhao W, Zhang H, Lai L, Ding C, Chen L, Ding J. Advances in the Study of Etiology and Molecular Mechanisms of Sensorineural Hearing Loss. Cell Biochem Biophys 2024:10.1007/s12013-024-01344-3. [PMID: 38849694 DOI: 10.1007/s12013-024-01344-3] [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] [Accepted: 05/29/2024] [Indexed: 06/09/2024]
Abstract
Sensorineural hearing loss (SNHL), a multifactorial progressive disorder, results from a complex interplay of genetic and environmental factors, with its underlying mechanisms remaining unclear. Several pathological factors are believed to contribute to SNHL, including genetic factors, ion homeostasis, cell apoptosis, immune inflammatory responses, oxidative stress, hormones, metabolic syndrome, human cytomegalovirus infection, mitochondrial damage, and impaired autophagy. These factors collectively interact and play significant roles in the onset and progression of SNHL. The present review offers a comprehensive overview of the various factors that contribute to SNHL, emphasizes recent developments in understanding its etiology, and explores relevant preventive and intervention measures.
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Affiliation(s)
- Cairong He
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China
| | - Hongcun Gai
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China
| | - Wen Zhao
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China
| | - Haiqin Zhang
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China
| | - Lin Lai
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China
| | - Chenyu Ding
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China
| | - Lin Chen
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China
| | - Jie Ding
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, 550025, Guizhou, China.
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Graziano B, Wang L, White OR, Kaplan DH, Fernandez-Abascal J, Bianchi L. Glial KCNQ K + channels control neuronal output by regulating GABA release from glia in C. elegans. Neuron 2024; 112:1832-1847.e7. [PMID: 38460523 PMCID: PMC11156561 DOI: 10.1016/j.neuron.2024.02.013] [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: 10/04/2023] [Revised: 01/22/2024] [Accepted: 02/16/2024] [Indexed: 03/11/2024]
Abstract
KCNQs are voltage-gated K+ channels that control neuronal excitability and are mutated in epilepsy and autism spectrum disorder (ASD). KCNQs have been extensively studied in neurons, but their function in glia is unknown. Using voltage, calcium, and GABA imaging, optogenetics, and behavioral assays, we show here for the first time in Caenorhabditis elegans (C. elegans) that glial KCNQ channels control neuronal excitability by mediating GABA release from glia via regulation of the function of L-type voltage-gated Ca2+ channels. Further, we show that human KCNQ channels have the same role when expressed in nematode glia, underscoring conservation of function across species. Finally, we show that pathogenic loss-of-function and gain-of-function human KCNQ2 mutations alter glia-to-neuron GABA signaling in distinct ways and that the KCNQ channel opener retigabine exerts rescuing effects. This work identifies glial KCNQ channels as key regulators of neuronal excitability via control of GABA release from glia.
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Affiliation(s)
- Bianca Graziano
- Department Physiology and Biophysics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Lei Wang
- Department Physiology and Biophysics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Olivia R White
- Department Physiology and Biophysics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Daryn H Kaplan
- Department Physiology and Biophysics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Jesus Fernandez-Abascal
- Department Physiology and Biophysics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Laura Bianchi
- Department Physiology and Biophysics, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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Liu W, Li H, Kämpfe Nordström C, Danckwardt-Lillieström N, Agrawal S, Ladak HM, Rask-Andersen H. Immuno-surveillance and protection of the human cochlea. Front Neurol 2024; 15:1355785. [PMID: 38817543 PMCID: PMC11137295 DOI: 10.3389/fneur.2024.1355785] [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: 12/14/2023] [Accepted: 02/21/2024] [Indexed: 06/01/2024] Open
Abstract
Background Despite its location near infection-prone areas, the human inner ear demonstrates remarkable resilience. This suggests that there are inherent instruments deterring the invasion and spread of pathogens into the inner ear. Here, we combined high-resolution light microscopy, super-resolution immunohistochemistry (SR-SIM) and synchrotron phase contrast imaging (SR-PCI) to identify the protection and barrier systems in the various parts of the human inner ear, focusing on the lateral wall, spiral ganglion, and endolymphatic sac. Materials and methods Light microscopy was conducted on mid-modiolar, semi-thin sections, after direct glutaraldehyde/osmium tetroxide fixation. The tonotopic locations were estimated using SR-PCI and 3D reconstruction in cadaveric specimens. The sections were analyzed for leucocyte and macrophage activity, and the results were correlated with immunohistochemistry using confocal microscopy and SR-SIM. Results Light microscopy revealed unprecedented preservation of cell anatomy and several macrophage-like cells that were localized in the cochlea. Immunohistochemistry demonstrated IBA1 cells frequently co-expressing MHC II in the spiral ganglion, nerve fibers, lateral wall, spiral limbus, and tympanic covering layer at all cochlear turns as well as in the endolymphatic sac. RNAscope assays revealed extensive expression of fractalkine gene transcripts in type I spiral ganglion cells. CD4 and CD8 cells occasionally surrounded blood vessels in the modiolus and lateral wall. TMEM119 and P2Y12 were not expressed, indicating that the cells labeled with IBA1 were not microglia. The round window niche, compact basilar membrane, and secondary spiral lamina may form protective shields in the cochlear base. Discussion The results suggest that the human cochlea is surveilled by dwelling and circulating immune cells. Resident and blood-borne macrophages may initiate protective immune responses via chemokine signaling in the lateral wall, spiral lamina, and spiral ganglion at different frequency locations. Synchrotron imaging revealed intriguing protective barriers in the base of the cochlea. The role of the endolymphatic sac in human inner ear innate and adaptive immunity is discussed.
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Affiliation(s)
- Wei Liu
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | - Hao Li
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | - Charlotta Kämpfe Nordström
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | | | - Sumit Agrawal
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
- Department of Medical Biophysics, Western University, London, ON, Canada
- Department of Electrical and Computer Engineering, Western University, London, ON, Canada
| | - Hanif M. Ladak
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
- Department of Medical Biophysics, Western University, London, ON, Canada
- Department of Electrical and Computer Engineering, Western University, London, ON, Canada
| | - Helge Rask-Andersen
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
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Bovee S, Klump GM, Köppl C, Pyott SJ. The Stria Vascularis: Renewed Attention on a Key Player in Age-Related Hearing Loss. Int J Mol Sci 2024; 25:5391. [PMID: 38791427 PMCID: PMC11121695 DOI: 10.3390/ijms25105391] [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: 04/13/2024] [Revised: 05/08/2024] [Accepted: 05/10/2024] [Indexed: 05/26/2024] Open
Abstract
Age-related hearing loss (HL), or presbycusis, is a complex and heterogeneous condition, affecting a significant portion of older adults and involving various interacting mechanisms. Metabolic presbycusis, a type of age-related HL, is characterized by the dysfunction of the stria vascularis, which is crucial for maintaining the endocochlear potential necessary for hearing. Although attention on metabolic presbycusis has waned in recent years, research continues to identify strial pathology as a key factor in age-related HL. This narrative review integrates past and recent research, bridging findings from animal models and human studies, to examine the contributions of the stria vascularis to age-related HL. It provides a brief overview of the structure and function of the stria vascularis and then examines mechanisms contributing to age-related strial dysfunction, including altered ion transport, changes in pigmentation, inflammatory responses, and vascular atrophy. Importantly, this review outlines the contribution of metabolic mechanisms to age-related HL, highlighting areas for future research. It emphasizes the complex interdependence of metabolic and sensorineural mechanisms in the pathology of age-related HL and highlights the importance of animal models in understanding the underlying mechanisms. The comprehensive and mechanistic investigation of all factors contributing to age-related HL, including cochlear metabolic dysfunction, remains crucial to identifying the underlying mechanisms and developing personalized, protective, and restorative treatments.
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Affiliation(s)
- Sonny Bovee
- Department of Neuroscience, School of Medicine and Health Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany; (S.B.); (G.M.K.); (C.K.)
| | - Georg M. Klump
- Department of Neuroscience, School of Medicine and Health Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany; (S.B.); (G.M.K.); (C.K.)
- Cluster of Excellence “Hearing4all”, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
- Research Centre Neurosensory Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
| | - Christine Köppl
- Department of Neuroscience, School of Medicine and Health Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany; (S.B.); (G.M.K.); (C.K.)
- Cluster of Excellence “Hearing4all”, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
- Research Centre Neurosensory Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany
| | - Sonja J. Pyott
- Department of Otorhinolaryngology/Head and Neck Surgery, University Medical Center Groningen, University of Groningen, P.O. Box 30.001, 9700 RB Groningen, The Netherlands
- The Research School of Behavioural and Cognitive Neurosciences, University of Groningen, P.O. Box 30.001, 9700 RB Groningen, The Netherlands
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Ke Y, Ma X, Jing Y, Diao T, Yu L. The Breakdown of Blood-Labyrinth Barrier Makes it Easier for Drugs to Enter the Inner Ear. Laryngoscope 2024; 134:2377-2386. [PMID: 37987231 DOI: 10.1002/lary.31194] [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: 08/02/2023] [Revised: 10/13/2023] [Accepted: 11/06/2023] [Indexed: 11/22/2023]
Abstract
PURPOSE This study aimed to investigate dynamic change of permeability of blood-labyrinth barrier (BLB) after noise exposure and its effect on the drug delivery efficiency of systemic administration. METHODS Gadopentetate dimeglumine (Gd-DTPA) and dexamethasone (DEX) were used as tracers, and magnetic resonance imaging (MRI) and immunofluorescence were used to observe the change of the BLB after strong noise exposure in guinea pigs. High-performance liquid chromatography-mass spectrometry (LC-MS) was used to observe the effect of the breakdown of BLB after noise exposure on the drug delivery efficiency of intravenous DEX. The guinea pigs were divided into 6 groups: normal group (N), 1, 3, 5, 8, and 12 days after noise exposure groups (P1, P3, P5, P8, P12), with 5 animals in each group. RESULTS The BLB changes dynamically after noise exposure. Increased permeability of the blood-endolymph barrier, the endolymph-perilymph barrier, and the blood-nerve barrier was observed at days 1-3, 1-5, and 1-8, respectively, after noise exposure in guinea pigs. Higher drug concentration in the cochlear tissue was obtained by intravenous administration of DEX in guinea pigs during the time window of increased permeability of the BLB. CONCLUSION After noise exposure, the increased BLB permeability makes it easier for drugs to enter the inner ear from blood. In guinea pigs, 1-8 days after strong noise exposure, the drug delivery efficiency of systemic administration increased. After 8 days, the efficiency gradually returned to normal level. 1-8 days after noise exposure may be the best intervention time for systemic administration. LEVEL OF EVIDENCE NA Laryngoscope, 134:2377-2386, 2024.
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Affiliation(s)
- Yujie Ke
- Department of Otorhinolaryngology, Peking University People's Hospital, Beijing, China
| | - Xin Ma
- Department of Otorhinolaryngology, Peking University People's Hospital, Beijing, China
| | - Yuanyuan Jing
- Department of Otorhinolaryngology, Peking University People's Hospital, Beijing, China
| | - Tongxiang Diao
- Department of Otorhinolaryngology, Peking University People's Hospital, Beijing, China
| | - Lisheng Yu
- Department of Otorhinolaryngology, Peking University People's Hospital, Beijing, China
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Strepay D, Olszewski RT, Nixon S, Korrapati S, Adadey S, Griffith AJ, Su Y, Liu J, Vishwasrao H, Gu S, Saunders T, Roux I, Hoa M. Transgenic Tg(Kcnj10-ZsGreen) fluorescent reporter mice allow visualization of intermediate cells in the stria vascularis. Sci Rep 2024; 14:3038. [PMID: 38321040 PMCID: PMC10847169 DOI: 10.1038/s41598-024-52663-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 01/22/2024] [Indexed: 02/08/2024] Open
Abstract
The stria vascularis (SV) is a stratified epithelium in the lateral wall of the mammalian cochlea, responsible for both endolymphatic ion homeostasis and generation of the endocochlear potential (EP) critical for normal hearing. The SV has three layers consisting predominantly of basal, intermediate, and marginal cells. Intermediate and marginal cells form an intricate interdigitated network of cell projections making discrimination of the cells challenging. To enable intermediate cell visualization, we engineered by BAC transgenesis, reporter mouse lines expressing ZsGreen fluorescent protein under the control of Kcnj10 promoter and regulatory sequences. Kcnj10 encodes KCNJ10 protein (also known as Kir4.1 or Kir1.2), an ATP-sensitive inwardly-rectifying potassium channel critical to EP generation, highly expressed in SV intermediate cells. In these transgenic mice, ZsGreen fluorescence mimics Kcnj10 endogenous expression in the cochlea and was detected in the intermediate cells of the SV, in the inner phalangeal cells, Hensen's, Deiters' and pillar cells, in a subset of spiral ganglion neurons, and in glial cells. We show that expression of the transgene in hemizygous mice does not alter auditory function, nor EP. These transgenic Tg(Kcnj10-ZsGreen) mice allow live and fixed tissue visualization of ZsGreen-expressing intermediate cells and will facilitate future studies of stria vascularis cell function.
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Affiliation(s)
- Dillon Strepay
- Auditory Development and Restoration Program, Neurotology Branch, National Institute On Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, 35 Convent Dr., Room 1F-226, Bethesda, MD, 20892-3745, USA
| | - Rafal T Olszewski
- Auditory Development and Restoration Program, Neurotology Branch, National Institute On Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, 35 Convent Dr., Room 1F-226, Bethesda, MD, 20892-3745, USA
| | - Sydney Nixon
- Auditory Development and Restoration Program, Neurotology Branch, National Institute On Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, 35 Convent Dr., Room 1F-226, Bethesda, MD, 20892-3745, USA
| | - Soumya Korrapati
- Auditory Development and Restoration Program, Neurotology Branch, National Institute On Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, 35 Convent Dr., Room 1F-226, Bethesda, MD, 20892-3745, USA
| | - Samuel Adadey
- Auditory Development and Restoration Program, Neurotology Branch, National Institute On Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, 35 Convent Dr., Room 1F-226, Bethesda, MD, 20892-3745, USA
| | - Andrew J Griffith
- Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Yijun Su
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD, USA
| | - Jiamin Liu
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD, USA
| | - Harshad Vishwasrao
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD, USA
| | - Shoujun Gu
- Auditory Development and Restoration Program, Neurotology Branch, National Institute On Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, 35 Convent Dr., Room 1F-226, Bethesda, MD, 20892-3745, USA
| | - Thomas Saunders
- Transgenic Animal Model Core, Biomedical Research Core Facility, University of Michigan, Ann Arbor, MI, USA
| | - Isabelle Roux
- Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, USA
| | - Michael Hoa
- Auditory Development and Restoration Program, Neurotology Branch, National Institute On Deafness and Other Communication Disorders, National Institutes of Health, Porter Neuroscience Research Center, 35 Convent Dr., Room 1F-226, Bethesda, MD, 20892-3745, USA.
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10
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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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11
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Choi JS, Ahn YJ, Lee S, Park DJ, Park J, Ha SM, Seo YJ. Role of Kir4.1 Channels in Aminoglycoside-Induced Ototoxicity of Hair Cells. BIOMED RESEARCH INTERNATIONAL 2023; 2023:4191999. [PMID: 38143588 PMCID: PMC10748730 DOI: 10.1155/2023/4191999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 10/27/2023] [Accepted: 11/14/2023] [Indexed: 12/26/2023]
Abstract
The Kir4.1 channel, an inwardly rectifying potassium ion (K+) channel, is located in the hair cells of the organ of Corti as well as the intermediate cells of the stria vascularis. The Kir4.1 channel has a crucial role in the generation of endolymphatic potential and maintenance of the resting membrane potential. However, the role and functions of the Kir4.1 channel in the progenitor remain undescribed. To observe the role of Kir4.1 in the progenitor treated with the one-shot ototoxic drugs (kanamycin and furosemide), we set the proper condition in culturing Immortomouse-derived HEI-OC1 cells to express the potassium-related channels well. And also, that was reproduced in mice experiments to show the important role of Kir4.1 in the survival of hair cells after treating the ototoxicity drugs. In our results, when kanamycin and furosemide drugs were cotreated with HEI-OC1 cells, the Kir4.1 channel did not change, but the expression levels of the NKCC1 cotransporter and KCNQ4 channel are decreased. This shows that inward and outward channels were blocked by the two drugs (kanamycin and furosemide). However, noteworthy here is that the expression level of Kir4.1 channel increased when kanamycin was treated alone. This shows that Kir4.1, an inwardly rectifying potassium channel, acts as an outward channel in place of the corresponding channel when the KCNQ4 channel, an outward channel, is blocked. These results suggest that the Kir4.1 channel has a role in maintaining K+ homeostasis in supporting cells, with K+ concentration compensator when the NKCC1 cotransporter and Kv7.4 (KCNQ4) channels are deficient.
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Affiliation(s)
- Jin Sil Choi
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Ye Ji Ahn
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - SuHoon Lee
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Dong Jun Park
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - JeongEun Park
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Sun Mok Ha
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Young Joon Seo
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
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12
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Fritzsch B, Elliott KL. Fish hearing revealed: Do we understand hearing in critical fishes and marine tetrapods. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 154:3019-3026. [PMID: 37955566 PMCID: PMC10769566 DOI: 10.1121/10.0022355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 09/26/2023] [Accepted: 09/27/2023] [Indexed: 11/14/2023]
Abstract
Hearing evolved in lampreys with a frequency range of 50-200 Hz. This hearing range is comparable to that of elasmobranchs, most non-teleosts, and lungfish. Elasmobranchs most likely use the saccule and the papilla neglecta (PN) for hearing. In non-teleosts and teleosts, lungfish, and certain tetrapods the saccule is the likely sensor for sound reception while the lagena and the PN are important for gravistatic sensing. Coelacanth and most tetrapods have a basilar papilla (BP) for hearing. In coelacanth and tetrapods, the hair cells of the BP are in contact with a basilar and a tectorial membrane. These membranes transmit mechanical vibrations. A cochlear aqueduct (CA) provides a connection between the cerebrospinal fluid that has a sodium rich space in coelacanth and tetrapods while the potassium rich endolymph is known in vertebrates. A unique feature is known in basic sarcopterygians, the intracranial joint, that never developed in actinopterygians and has been lost in lungfish and tetrapods. The BP in coelacanths is thought to generate pressure with the intracranial joint that will be transmitted to the CA. Lungs or a swim bladder are not forming in Chondrichthyes, structures that have a major impact on hearing in teleosts and tetrapods.
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Affiliation(s)
- Bernd Fritzsch
- Department of Biology & Department of Otolaryngology, The University of Iowa, Iowa City, Iowa 52242, USA
| | - Karen L Elliott
- Department of Biology & Department of Otolaryngology, The University of Iowa, Iowa City, Iowa 52242, USA
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13
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Strepay D, Olszewski RT, Nixon S, Korrapati S, Adadey S, Griffith AJ, Su Y, Liu J, Vishwasrao H, Gu S, Saunders T, Roux I, Hoa M. Transgenic Tg(Kcnj10-ZsGreen) Fluorescent Reporter Mice Allow Visualization of Intermediate Cells in the Stria Vascularis. RESEARCH SQUARE 2023:rs.3.rs-3393161. [PMID: 37886521 PMCID: PMC10602146 DOI: 10.21203/rs.3.rs-3393161/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
The stria vascularis (SV) is a stratified epithelium in the lateral wall of the mammalian cochlea, responsible for both endolymphatic ion homeostasis and generation of the endocochlear potential (EP) critical for normal hearing. The SV has three layers consisting predominantly of basal, intermediate, and marginal cells. Intermediate and marginal cells form an intricate interdigitated network of cell projections making discrimination of the cells challenging. To enable intermediate cell visualization, we engineered by BAC transgenesis, reporter mouse lines expressing ZsGreen fluorescent protein under the control of Kcnj10 promoter and regulatory sequences. Kcnj10 encodes KCNJ10 protein (also known as Kir4.1 or Kir1.2), an ATP-sensitive inwardly-rectifying potassium channel critical to EP generation, highly expressed in SV intermediate cells. In these transgenic mice, ZsGreen fluorescence mimics Kcnj10 endogenous expression in the cochlea and was detected in the intermediate cells of the SV, in the inner phalangeal cells, Hensen's, Deiters' and pillar cells, in a subset of spiral ganglion neurons, and in glial cells. We show that expression of the transgene in hemizygous mice does not alter auditory function, nor EP These transgenic Tg(Kcnj10-ZsGreen) mice allow live and fixed tissue visualization of ZsGreen-expressing intermediate cells and will facilitate future studies of stria vascularis cell function.
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Affiliation(s)
- Dillon Strepay
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health
| | - Rafal T Olszewski
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health
| | - Sydney Nixon
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health
| | - Soumya Korrapati
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health
| | - Samuel Adadey
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health
| | - Andrew J Griffith
- Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, National Institutes of Health
| | - Yijun Su
- Advanced Imaging and Microscopy Resource, National Institutes of Health
| | - Jiamin Liu
- Advanced Imaging and Microscopy Resource, National Institutes of Health
| | | | - Shoujun Gu
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health
| | - Thomas Saunders
- Transgenic Animal Model Core, Biomedical Research Core Facility, University of Michigan
| | - Isabelle Roux
- Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, National Institutes of Health
| | - Michael Hoa
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health
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14
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Shi X. Research advances in cochlear pericytes and hearing loss. Hear Res 2023; 438:108877. [PMID: 37651921 PMCID: PMC10538405 DOI: 10.1016/j.heares.2023.108877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 08/03/2023] [Accepted: 08/18/2023] [Indexed: 09/02/2023]
Abstract
Pericytes are specialized mural cells surrounding endothelial cells in microvascular beds. They play a role in vascular development, blood flow regulation, maintenance of blood-tissue barrier integrity, and control of angiogenesis, tissue fibrosis, and wound healing. In recent decades, understanding of the critical role played by pericytes in retina, brain, lung, and kidney has seen significant progress. The cochlea contains a large population of pericytes. However, the role of cochlear pericytes in auditory pathophysiology is, by contrast, largely unknown. The present review discusses recent progress in identifying cochlear pericytes, mapping their distribution, and defining their role in regulating blood flow, controlling the blood-labyrinth barrier (BLB) and angiogenesis, and involvement in different types of hearing loss.
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Affiliation(s)
- Xiaorui Shi
- Department of Otolaryngology/Head & Neck Surgery, Oregon Hearing Research Center (NRC04), Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239-3098, USA.
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15
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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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16
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Koh JY, Affortit C, Ranum PT, West C, Walls WD, Yoshimura H, Shao JQ, Mostaert B, Smith RJH. Single-cell RNA-sequencing of stria vascularis cells in the adult Slc26a4 -/- mouse. BMC Med Genomics 2023; 16:133. [PMID: 37322474 PMCID: PMC10268361 DOI: 10.1186/s12920-023-01549-0] [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: 01/20/2023] [Accepted: 05/15/2023] [Indexed: 06/17/2023] Open
Abstract
BACKGROUND The primary pathological alterations of Pendred syndrome are endolymphatic pH acidification and luminal enlargement of the inner ear. However, the molecular contributions of specific cell types remain poorly characterized. Therefore, we aimed to identify pH regulators in pendrin-expressing cells that may contribute to the homeostasis of endolymph pH and define the cellular pathogenic mechanisms that contribute to the dysregulation of cochlear endolymph pH in Slc26a4-/- mice. METHODS We used single-cell RNA sequencing to identify both Slc26a4-expressing cells and Kcnj10-expressing cells in wild-type (WT, Slc26a4+/+) and Slc26a4-/- mice. Bioinformatic analysis of expression data confirmed marker genes defining the different cell types of the stria vascularis. In addition, specific findings were confirmed at the protein level by immunofluorescence. RESULTS We found that spindle cells, which express pendrin, contain extrinsic cellular components, a factor that enables cell-to-cell communication. In addition, the gene expression profile informed the pH of the spindle cells. Compared to WT, the transcriptional profiles in Slc26a4-/- mice showed downregulation of extracellular exosome-related genes in spindle cells. Immunofluorescence studies in spindle cells of Slc26a4-/- mice validated the increased expression of the exosome-related protein, annexin A1, and the clathrin-mediated endocytosis-related protein, adaptor protein 2. CONCLUSION Overall, cell isolation of stria vascularis from WT and Slc26a4-/- samples combined with cell type-specific transcriptomic analyses revealed pH-dependent alternations in spindle cells and intermediate cells, inspiring further studies into the dysfunctional role of stria vascularis cells in SLC26A4-related hearing loss.
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Affiliation(s)
- Jin-Young Koh
- Roy J. Carver Department of Biomedical Engineering, College of Engineering, University of Iowa, University of Iowa, Iowa City, IA, USA
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Corentin Affortit
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Paul T Ranum
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia Research Institute, Philadelphia, PA, USA
| | - Cody West
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - William D Walls
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Hidekane Yoshimura
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
- Department of Otorhinolaryngology - Head and Neck Surgery, Shinshu University School of Medicine, Matsumoto, Japan
| | - Jian Q Shao
- Central Microscopy Research Facility, University of Iowa, Iowa City, IA, USA
| | - Brian Mostaert
- Department of Otolaryngology, Head and Neck Surgery, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Richard J H Smith
- Roy J. Carver Department of Biomedical Engineering, College of Engineering, University of Iowa, University of Iowa, Iowa City, IA, USA.
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.
- Department of Otolaryngology, Head and Neck Surgery, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.
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17
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Fritzsch B, Schultze HP, Elliott KL. The evolution of the various structures required for hearing in Latimeria and tetrapods. IBRO Neurosci Rep 2023; 14:325-341. [PMID: 37006720 PMCID: PMC10063410 DOI: 10.1016/j.ibneur.2023.03.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Sarcopterygians evolved around 415 Ma and have developed a unique set of features, including the basilar papilla and the cochlear aqueduct of the inner ear. We provide an overview that shows the morphological integration of the various parts needed for hearing, e.g., basilar papilla, tectorial membrane, cochlear aqueduct, lungs, and tympanic membranes. The lagena of the inner ear evolved from a common macula of the saccule several times. It is near this lagena where the basilar papilla forms in Latimeria and tetrapods. The basilar papilla is lost in lungfish, certain caecilians and salamanders, but is transformed into the cochlea of mammals. Hearing in bony fish and tetrapods involves particle motion to improve sound pressure reception within the ear but also works without air. Lungs evolved after the chondrichthyans diverged and are present in sarcopterygians and actinopterygians. Lungs open to the outside in tetraposomorph sarcopterygians but are transformed from a lung into a swim bladder in ray-finned fishes. Elasmobranchs, polypterids, and many fossil fishes have open spiracles. In Latimeria, most frogs, and all amniotes, a tympanic membrane covering the spiracle evolved independently. The tympanic membrane is displaced by pressure changes and enabled tetrapods to perceive airborne sound pressure waves. The hyomandibular bone is associated with the spiracle/tympanic membrane in actinopterygians and piscine sarcopterygians. In tetrapods, it transforms into the stapes that connects the oval window of the inner ear with the tympanic membrane and allows hearing at higher frequencies by providing an impedance matching and amplification mechanism. The three characters-basilar papilla, cochlear aqueduct, and tympanic membrane-are fluid related elements in sarcopterygians, which interact with a set of unique features in Latimeria. Finally, we explore the possible interaction between the unique intracranial joint, basicranial muscle, and an enlarged notochord that allows fluid flow to the foramen magnum and the cochlear aqueduct which houses a comparatively small brain.
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Affiliation(s)
- Bernd Fritzsch
- Department of Biology & Department of Otolaryngology, University of Iowa, IA, USA
- Correspondence to: Department of Biology & Department of Otolaryngology, University of Iowa, Iowa City, IA, 52242, USA.
| | | | - Karen L. Elliott
- Department of Biology & Department of Otolaryngology, University of Iowa, IA, USA
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18
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Li H, Staxäng K, Hodik M, Melkersson KG, Rask-Andersen H. The ultrastructure of a stria vascularis in the auditory organ of the cuban crocodile ( Crocodylus rhombifer). Front Cell Dev Biol 2023; 11:1129074. [PMID: 36891513 PMCID: PMC9986273 DOI: 10.3389/fcell.2023.1129074] [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: 12/21/2022] [Accepted: 02/06/2023] [Indexed: 02/22/2023] Open
Abstract
Background: An endocochlear potential (EP) exists in the mammalian cochlea generated by the stria vascularis and an associated fibrocyte network. It plays an essential role for sensory cell function and hearing sensitivity. In non-mammalian ectothermic animals the endocochlear potential is low and its origin somewhat unclear. In this study, we explored the crocodilian auditory organ and describe the fine structure of a stria vascularis epithelium that has not been verified in birds. Material and Methods: Three Cuban crocodiles (Crocodylus rhombifer) were analyzed with light and transmission electron microscopy. The ears were fixed in glutaraldehyde The temporal bones were drilled out and decalcified. The ears were dehydrated, and embedded and was followed by semi-thin and thin sectioning. Results: The fine structure of the crocodile auditory organ including the papilla basilaris and endolymph system was outlined. The upper roof of the endolymph compartment was specialized into a Reissner membrane and tegmentum vasculosum. At the lateral limbus an organized, multilayered, vascularized epithelium or stria vascularis was identified. Discussion: Electron microscopy demonstrates that the auditory organ in Crocodylus rhombifer, unlike in birds, contains a stria vascularis epithelium separate from the tegmentum vasculosum. It is believed to secrete endolymph and to generate a low grade endocochlear potential. It may regulate endolymph composition and optimize hearing sensitivity alongside the tegmentum vasculosum. It could represent a parallel evolution essential for the adaptation of crocodiles to their diverse habitats.
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Affiliation(s)
- Hao Li
- Department of Surgical Sciences, Head and Neck Surgery, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
| | - Karin Staxäng
- The Rudbeck TEM laboratory, Uppsala University, Uppsala, Sweden
| | - Monika Hodik
- The Rudbeck TEM laboratory, Uppsala University, Uppsala, Sweden
| | | | - Helge Rask-Andersen
- Department of Surgical Sciences, Head and Neck Surgery, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
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19
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Requena T, Keder A, zur Lage P, Albert JT, Jarman AP. A Drosophila model for Meniere's disease: Dystrobrevin is required for support cell function in hearing and proprioception. Front Cell Dev Biol 2022; 10:1015651. [PMID: 36438562 PMCID: PMC9688402 DOI: 10.3389/fcell.2022.1015651] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 10/27/2022] [Indexed: 08/04/2023] Open
Abstract
Meniere's disease (MD) is an inner ear disorder characterised by recurrent vertigo attacks associated with sensorineural hearing loss and tinnitus. Evidence from epidemiology and Whole Exome Sequencing (WES) suggests a genetic susceptibility involving multiple genes, including α-Dystrobrevin (DTNA). Here we investigate a Drosophila model. We show that mutation, or knockdown, of the DTNA orthologue in Drosophila, Dystrobrevin (Dyb), results in defective proprioception and impaired function of Johnston's Organ (JO), the fly's equivalent of the inner ear. Dyb and another component of the dystrophin-glycoprotein complex (DGC), Dystrophin (Dys), are expressed in support cells within JO. Their specific locations suggest that they form part of support cell contacts, thereby helping to maintain the integrity of the hemolymph-neuron diffusion barrier, which is equivalent to a blood-brain barrier. These results have important implications for the human condition, and notably, we note that DTNA is expressed in equivalent cells of the mammalian inner ear.
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Affiliation(s)
- T. Requena
- Biomedical Sciences: Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, United Kingdom
- Division of Functional Genetics and Development, The Royal Dick School of Veterinary Sciences, The Roslin Institute, The University of Edinburgh, Edinburgh, United Kingdom
| | - A. Keder
- Ear Institute, University College London, London, United Kingdom
| | - P. zur Lage
- Biomedical Sciences: Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, United Kingdom
| | - J. T. Albert
- Ear Institute, University College London, London, United Kingdom
| | - A. P. Jarman
- Biomedical Sciences: Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, United Kingdom
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20
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Isgrig K, Ishibashi Y, Lee HJ, Zhu J, Grati M, Bennett J, Griffith AJ, Roux I, Chien WW. AAV8BP2 and AAV8 transduce the mammalian cochlear lateral wall and endolymphatic sac with high efficiency. Mol Ther Methods Clin Dev 2022; 26:371-383. [PMID: 36034771 PMCID: PMC9386391 DOI: 10.1016/j.omtm.2022.07.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 07/20/2022] [Indexed: 12/04/2022]
Abstract
Inner ear gene therapy using adeno-associated viruses (AAVs) has been successfully applied to several mouse models of hereditary hearing loss to improve their auditory function. While most inner ear gene therapy studies have focused on the mechanosensory hair cells and supporting cells in the organ of Corti, the cochlear lateral wall and the endolymphatic sac have not garnered much attention. The cochlear lateral wall and the endolymphatic sac play critical roles in inner ear ionic and fluid homeostasis. Mutations in genes expressed in the cochlear lateral wall and the endolymphatic sac are present in a large percentage of patients with hereditary hearing loss. In this study, we examine the transduction patterns and efficiencies of conventional (AAV2 and AAV8) and synthetic (AAV2.7m8, AAV8BP2, and Anc80L65) AAVs in the mouse inner ear. We found that AAV8BP2 and AAV8 are capable of transducing the marginal cells and intermediate cells in the stria vascularis. These two AAVs can also transduce the epithelial cells of the endolymphatic sac. Our data suggest that AAV8BP2 and AAV8 are highly useful viral vectors for gene therapy studies targeting the cochlear lateral wall and the endolymphatic sac.
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Affiliation(s)
- Kevin Isgrig
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, Bethesda, MD, USA
| | - Yasuko Ishibashi
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, Bethesda, MD, USA
| | - Hyun Jae Lee
- Otolaryngology Branch, NIDCD, National Institutes of Health, Bethesda, MD, USA
| | - Jianliang Zhu
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, Bethesda, MD, USA
| | - Mhamed Grati
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, Bethesda, MD, USA
| | - Jean Bennett
- Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Andrew J. Griffith
- Otolaryngology Branch, NIDCD, National Institutes of Health, Bethesda, MD, USA
- Department of Otolaryngology, University of Tennessee College of Medicine, Memphis, TN, USA
| | - Isabelle Roux
- Otolaryngology Branch, NIDCD, National Institutes of Health, Bethesda, MD, USA
| | - Wade W. Chien
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, Bethesda, MD, USA
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins School of Medicine, Baltimore, MD, USA
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21
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Li H, Staxäng K, Hodik M, Melkersson KG, Rask-Andersen M, Rask-Andersen H. Regeneration in the Auditory Organ in Cuban and African Dwarf Crocodiles (Crocodylus rhombifer and Osteolaemus tetraspis) Can We Learn From the Crocodile How to Restore Our Hearing? Front Cell Dev Biol 2022; 10:934571. [PMID: 35859896 PMCID: PMC9289536 DOI: 10.3389/fcell.2022.934571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 06/08/2022] [Indexed: 11/16/2022] Open
Abstract
Background: In several non-mammalian species, auditory receptors undergo cell renewal after damage. This has raised hope of finding new options to treat human sensorineural deafness. Uncertainty remains as to the triggering mechanisms and whether hair cells are regenerated even under normal conditions. In the present investigation, we explored the auditory organ in the crocodile to validate possible ongoing natural hair cell regeneration. Materials and Methods: Two male Cuban crocodiles (Crocodylus rhombifer) and an adult male African Dwarf crocodile (Osteolaemus tetraspis) were analyzed using transmission electron microscopy and immunohistochemistry using confocal microscopy. The crocodile ears were fixed in formaldehyde and glutaraldehyde and underwent micro-computed tomography (micro-CT) and 3D reconstruction. The temporal bones were drilled out and decalcified. Results: The crocodile papilla basilaris contained tall (inner) and short (outer) hair cells surrounded by a mosaic of tightly connected supporting cells coupled with gap junctions. Afferent neurons with and without ribbon synapses innervated both hair cell types. Supporting cells occasionally showed signs of trans-differentiation into hair cells. They expressed the MAFA and SOX2 transcription factors. Supporting cells contained organelles that may transfer genetic information between cells, including the efferent nerve fibers during the regeneration process. The tectorial membrane showed signs of being replenished and its architecture being sculpted by extracellular exosome-like proteolysis. Discussion: Crocodilians seem to produce new hair cells during their life span from a range of supporting cells. Imposing efferent nerve fibers may play a role in regeneration and re-innervation of the auditory receptors, possibly triggered by apoptotic signals from wasted hair cells. Intercellular signaling may be accomplished by elaborate gap junction and organelle systems, including neural emperipolesis. Crocodilians seem to restore and sculpt their tectorial membranes throughout their lives.
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Affiliation(s)
- Hao Li
- Department of Surgical Sciences, Head and Neck Surgery, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
| | - Karin Staxäng
- The Rudbeck TEM Laboratory, BioVis Platform, Uppsala University, Uppasala, Swedan
| | - Monika Hodik
- The Rudbeck TEM Laboratory, BioVis Platform, Uppsala University, Uppasala, Swedan
| | | | - Mathias Rask-Andersen
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Helge Rask-Andersen
- Department of Surgical Sciences, Head and Neck Surgery, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
- *Correspondence: Helge Rask-Andersen,
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22
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Jang MW, Lim J, Park MG, Lee JH, Lee CJ. Active role of glia-like supporting cells in the organ of Corti: Membrane proteins and their roles in hearing. Glia 2022; 70:1799-1825. [PMID: 35713516 DOI: 10.1002/glia.24229] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 05/23/2022] [Accepted: 05/30/2022] [Indexed: 12/13/2022]
Abstract
The organ of Corti, located in the cochlea in the inner ear, is one of the major sensory organs involved in hearing. The organ of Corti consists of hair cells, glia-like supporting cells, and the cochlear nerve, which work in harmony to receive sound from the outer ear and transmit auditory signals to the cochlear nucleus in the auditory ascending pathway. In this process, maintenance of the endocochlear potential, with a high potassium gradient and clearance of electrolytes and biochemicals in the inner ear, is critical for normal sound transduction. There is an emerging need for a thorough understanding of each cell type involved in this process to understand the sophisticated mechanisms of the organ of Corti. Hair cells have long been thought to be active, playing a primary role in the cochlea in actively detecting and transmitting signals. In contrast, supporting cells are thought to be silent and function to support hair cells. However, growing lines of evidence regarding the membrane proteins that mediate ionic movement in supporting cells have demonstrated that supporting cells are not silent, but actively play important roles in normal signal transduction. In this review, we summarize studies that characterize diverse membrane proteins according to the supporting cell subtypes involved in cochlear physiology and hearing. This review contributes to a better understanding of supporting cell functions and facilitates the development of potential therapeutic tools for hearing loss.
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Affiliation(s)
- Minwoo Wendy Jang
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, Republic of Korea.,Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Republic of Korea
| | - Jiwoon Lim
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Republic of Korea.,IBS School, University of Science and Technology (UST), Daejeon, Republic of Korea
| | - Mingu Gordon Park
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, Republic of Korea.,Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Republic of Korea
| | - Jae-Hun Lee
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Republic of Korea
| | - C Justin Lee
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, Republic of Korea.,Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Republic of Korea.,IBS School, University of Science and Technology (UST), Daejeon, Republic of Korea
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23
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Ruan C, Mao X, Chen S, Wu S, Wang W. Subclinical Atherosclerosis Could Increase the Risk of Hearing Impairment in Males: A Community-Based Cross-Sectional Survey of the Kailuan Study. Front Neurosci 2022; 16:813628. [PMID: 35546882 PMCID: PMC9082793 DOI: 10.3389/fnins.2022.813628] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 02/01/2022] [Indexed: 01/19/2023] Open
Abstract
Objective The relationship between subclinical atherosclerosis and hearing impairment (HI) has not been widely considered. Brachial ankle pulse wave velocity (baPWV) is a good indicator of muscular artery elasticity and could be a feasible method to screen for subclinical atherosclerosis. Our study aimed to elucidate the relationship between baPWV and HI. Methods This cross-sectional study was based on the Kailuan cohort. All participants completed a standardized questionnaire and underwent physical examinations and laboratory assessments at recruitment. Since 2010, some participants received additional baPWV testing during follow-up visits, and some who were exposed to occupational hazards such as noise received a pure-tone average hearing threshold (PTA) test after 2014. Male subjects with a complete physical examination, baPWV, and PTA data were recruited for this study. HI was defined as PTA > 25 dB. Multivariate linear and multivariate logistic regression analyses were used to evaluate the relationship between baPWV and PTA or HI. Results Among 11,141 subjects, the age range was 18–65 years, with mean age of 43.3 ± 8.9 years, the average PTA was 20.54 ± 10.40 dB, and the detection rate of HI was 1,821/11,141 (16.3%). Subjects were divided into four subgroups according to baPWV quartile. As the baPWV quartile increased, age, systolic blood pressure, diastolic blood pressure, body mass index, total cholesterol, high-density-lipoprotein cholesterol, fasting blood glucose, PTA, and proportions of subjects reporting smoking, alcohol consumption, hypertension, and diabetes increased significantly (p < 0.05 for trend). The odds of HI were higher in the fourth quartile group [adjusted odds ratio (aOR): 1.33, 95% CI: 1.10–1.62] than in the first quartile group. For every 100 m/s increase in baPWV, the PTA increased by 13 dB (95% CI: 4–23). When we divided the subjects into young (5,478 subjects; age range 22–44 years; mean age 35.6 ± 5.5 years) or non-young subgroups (5,663 subjects; age range 45–65 years; mean age 50.7 ± 3.7 years) based on a cut-off age of 45 years, the aOR of the fourth quartile group increased to 2.65 (95% CI: 1.68–4.19), and the PTA increment increased to 18 dB (95% CI: 10–27) for every 100 m/s increase in baPWV in the young subgroup. However, this relationship became statistically insignificant in the non-young subgroup. Conclusion Our study revealed the quantitative relationship between baPWV and HI in the Kailuan cohort subjects, although the results are not universally consistent in different populations.
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Affiliation(s)
- Chunyu Ruan
- Department of Cardiology, Kailuan General Hospital, Tangshan, China
| | - Xiang Mao
- Department of Otorhinolaryngology Head and Neck Surgery, Tianjin First Central Hospital, Tianjin, China.,Institute of Otolaryngology of Tianjin, Tianjin, China.,Key Laboratory of Auditory Speech and Balance Medicine, Tianjin, China.,Key Medical Discipline of Tianjin (Otolaryngology), Tianjin, China.,Otolaryngology Clinical Quality Control Centre, Tianjin, China
| | - Shuohua Chen
- Department of Cardiology, Kailuan General Hospital, Tangshan, China
| | - Shouling Wu
- Department of Cardiology, Kailuan General Hospital, Tangshan, China
| | - Wei Wang
- Department of Otorhinolaryngology Head and Neck Surgery, Tianjin First Central Hospital, Tianjin, China.,Institute of Otolaryngology of Tianjin, Tianjin, China.,Key Laboratory of Auditory Speech and Balance Medicine, Tianjin, China.,Key Medical Discipline of Tianjin (Otolaryngology), Tianjin, China.,Otolaryngology Clinical Quality Control Centre, Tianjin, China
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24
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Kim SH, Choi JY. Purinergic signaling in the peripheral vestibular system. Purinergic Signal 2022; 18:165-176. [PMID: 35344126 DOI: 10.1007/s11302-022-09855-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 02/19/2022] [Indexed: 11/25/2022] Open
Abstract
The inner ear comprises the cochlea and vestibular system, which detect sound and acceleration stimulation, respectively. The function of the inner ear is regulated by ion transport activity among sensory epithelial cells, neuronal cells, non-sensory epithelial cells, and luminal fluid with a unique ionic composition of high [K+] and low [Na+], which enables normal hearing and balance maintenance. One of the important mechanisms regulating ion transport in the inner ear is purinergic signaling. Various purinergic receptors are distributed throughout inner ear epithelial cells and neuronal cells. To date, most studies have focused on the role of purinergic receptors in the cochlea, and few studies have examined these receptors in the vestibular system. As purinergic receptors play an important role in the cochlea, they would likely do the same in the vestibular system, which is fairly similar to the cochlea in cellular structure and function. Based on available studies performed to date, purinergic signaling is postulated to be involved in the regulation of ion homeostasis, protection of hair cells, otoconia formation, and regulation of electrical signaling from the sensory epithelium to vestibular neurons. In this review, the distribution and roles of purinergic receptors in the peripheral vestibular system are summarized and discussed.
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Affiliation(s)
- Sung Huhn Kim
- Department of Otorhinolaryngology, Yonsei University College of Medicine, 50-1 Yonsei-Ro, Seodaemun-Gu, Seoul, 03722, Republic of Korea
| | - Jae Young Choi
- Department of Otorhinolaryngology, Yonsei University College of Medicine, 50-1 Yonsei-Ro, Seodaemun-Gu, Seoul, 03722, Republic of Korea.
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25
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Thulasiram MR, Ogier JM, Dabdoub A. Hearing Function, Degeneration, and Disease: Spotlight on the Stria Vascularis. Front Cell Dev Biol 2022; 10:841708. [PMID: 35309932 PMCID: PMC8931286 DOI: 10.3389/fcell.2022.841708] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 01/20/2022] [Indexed: 11/21/2022] Open
Abstract
The stria vascularis (SV) is a highly vascularized tissue lining the lateral wall of the cochlea. The SV maintains cochlear fluid homeostasis, generating the endocochlear potential that is required for sound transduction. In addition, the SV acts as an important blood-labyrinth barrier, tightly regulating the passage of molecules from the blood into the cochlea. A healthy SV is therefore vital for hearing function. Degeneration of the SV is a leading cause of age-related hearing loss, and has been associated with several hearing disorders, including Norrie disease, Meniere's disease, Alport syndrome, Waardenburg syndrome, and Cytomegalovirus-induced hearing loss. Despite the SV's important role in hearing, there is still much that remains to be discovered, including cell-specific function within the SV, mechanisms of SV degeneration, and potential protective or regenerative therapies. In this review, we discuss recent discoveries elucidating the molecular regulatory networks of SV function, mechanisms underlying degeneration of the SV, and otoprotective strategies for preventing drug-induced SV damage. We also highlight recent clinical developments for treating SV-related hearing loss and discuss future research trajectories in the field.
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Affiliation(s)
- Matsya R Thulasiram
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Jacqueline M Ogier
- Biological Sciences, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Alain Dabdoub
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
- Biological Sciences, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
- Department of Otolaryngology–Head and Neck Surgery, University of Toronto, Toronto, ON, Canada
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26
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Spironolactone Ameliorates Cochlear Implant Induced Endolymphatic Hydrops. Otol Neurotol 2022; 43:685-693. [DOI: 10.1097/mao.0000000000003517] [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]
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27
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Badash I, Quiñones PM, Oghalai KJ, Wang J, Lui CG, Macias-Escriva F, Applegate BE, Oghalai JS. Endolymphatic Hydrops is a Marker of Synaptopathy Following Traumatic Noise Exposure. Front Cell Dev Biol 2021; 9:747870. [PMID: 34805158 PMCID: PMC8602199 DOI: 10.3389/fcell.2021.747870] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 10/20/2021] [Indexed: 12/28/2022] Open
Abstract
After acoustic trauma, there can be loss of synaptic connections between inner hair cells and auditory neurons in the cochlea, which may lead to hearing abnormalities including speech-in-noise difficulties, tinnitus, and hyperacusis. We have previously studied mice with blast-induced cochlear synaptopathy and found that they also developed a build-up of endolymph, termed endolymphatic hydrops. In this study, we used optical coherence tomography to measure endolymph volume in live CBA/CaJ mice exposed to various noise intensities. We quantified the number of synaptic ribbons and postsynaptic densities under the inner hair cells 1 week after noise exposure to determine if they correlated with acute changes in endolymph volume measured in the hours after the noise exposure. After 2 h of noise at an intensity of 95 dB SPL or below, both endolymph volume and synaptic counts remained normal. After exposure to 2 h of 100 dB SPL noise, mice developed endolymphatic hydrops and had reduced synaptic counts in the basal and middle regions of the cochlea. Furthermore, round-window application of hypertonic saline reduced the degree of endolymphatic hydrops that developed after 100 dB SPL noise exposure and partially prevented the reduction in synaptic counts in the cochlear base. Taken together, these results indicate that endolymphatic hydrops correlates with noise-induced cochlear synaptopathy, suggesting that these two pathologic findings have a common mechanistic basis.
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Affiliation(s)
- Ido Badash
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States
| | - Patricia M Quiñones
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States
| | - Kevin J Oghalai
- Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Juemei Wang
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States
| | - Christopher G Lui
- Department of Otolaryngology-Head and Neck Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Frank Macias-Escriva
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States
| | - Brian E Applegate
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States.,Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - John S Oghalai
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States.,Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
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28
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Shuster B, Casserly R, Lipford E, Olszewski R, Milon B, Viechweg S, Davidson K, Enoch J, McMurray M, Rutherford MA, Ohlemiller KK, Hoa M, Depireux DA, Mong JA, Hertzano R. Estradiol Protects against Noise-Induced Hearing Loss and Modulates Auditory Physiology in Female Mice. Int J Mol Sci 2021; 22:12208. [PMID: 34830090 PMCID: PMC8620009 DOI: 10.3390/ijms222212208] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/05/2021] [Accepted: 11/08/2021] [Indexed: 12/13/2022] Open
Abstract
Recent studies have identified sex-differences in auditory physiology and in the susceptibility to noise-induced hearing loss (NIHL). We hypothesize that 17β-estradiol (E2), a known modulator of auditory physiology, may underpin sex-differences in the response to noise trauma. Here, we gonadectomized B6CBAF1/J mice and used a combination of electrophysiological and histological techniques to study the effects of estrogen replacement on peripheral auditory physiology in the absence of noise exposure and on protection from NIHL. Functional analysis of auditory physiology in gonadectomized female mice revealed that E2-treatment modulated the peripheral response to sound in the absence of changes to the endocochlear potential compared to vehicle-treatment. E2-replacement in gonadectomized female mice protected against hearing loss following permanent threshold shift (PTS)- and temporary threshold shift (TTS)-inducing noise exposures. Histological analysis of the cochlear tissue revealed that E2-replacement mitigated outer hair cell loss and cochlear synaptopathy following noise exposure compared to vehicle-treatment. Lastly, using fluorescent in situ hybridization, we demonstrate co-localization of estrogen receptor-2 with type-1C, high threshold spiral ganglion neurons, suggesting that the observed protection from cochlear synaptopathy may occur through E2-mediated preservation of these neurons. Taken together, these data indicate the estrogen signaling pathways may be harnessed for the prevention and treatment of NIHL.
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Affiliation(s)
- Benjamin Shuster
- Department of Otorhinolaryngology—Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (B.S.); (R.C.); (E.L.); (B.M.); (M.M.)
| | - Ryan Casserly
- Department of Otorhinolaryngology—Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (B.S.); (R.C.); (E.L.); (B.M.); (M.M.)
| | - Erika Lipford
- Department of Otorhinolaryngology—Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (B.S.); (R.C.); (E.L.); (B.M.); (M.M.)
| | - Rafal Olszewski
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA; (R.O.); (M.H.)
| | - Béatrice Milon
- Department of Otorhinolaryngology—Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (B.S.); (R.C.); (E.L.); (B.M.); (M.M.)
| | - Shaun Viechweg
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (S.V.); (K.D.); (J.E.); (J.A.M.)
| | - Kanisa Davidson
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (S.V.); (K.D.); (J.E.); (J.A.M.)
| | - Jennifer Enoch
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (S.V.); (K.D.); (J.E.); (J.A.M.)
| | - Mark McMurray
- Department of Otorhinolaryngology—Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (B.S.); (R.C.); (E.L.); (B.M.); (M.M.)
| | - Mark A. Rutherford
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO 63110, USA; (M.A.R.); (K.K.O.)
| | - Kevin K. Ohlemiller
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO 63110, USA; (M.A.R.); (K.K.O.)
| | - Michael Hoa
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA; (R.O.); (M.H.)
| | | | - Jessica A. Mong
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (S.V.); (K.D.); (J.E.); (J.A.M.)
| | - Ronna Hertzano
- Department of Otorhinolaryngology—Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (B.S.); (R.C.); (E.L.); (B.M.); (M.M.)
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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29
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The disruption and hyperpermeability of blood-labyrinth barrier mediates cisplatin-induced ototoxicity. Toxicol Lett 2021; 354:56-64. [PMID: 34757176 DOI: 10.1016/j.toxlet.2021.10.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 10/21/2021] [Accepted: 10/27/2021] [Indexed: 12/20/2022]
Abstract
The ototoxic mechanisms of cisplatin on the organ of Corti and spiral ganglion neurons have been extensively studied, while few studies have been focused on the stria vascularis (SV). Herein, we verified the functional and morphological impairment in SV induced by a single injection of cisplatin (12 mg/kg, I.P.), represented by a reduction in Endocochlear Potentials (EP) and strial atrophy, and explored underlying mechanisms. Our results revealed increased extravasation of chromatic tracers (Evans blue dye and FITC-dextran) around microvessels after cisplatin exposure. The increased vascular permeability could be attributed to changes of pericytes (PCs) and perivascular-resident macrophage-like melanocytes (PVM/Ms) in number or morphology, as well as the enhanced level of HIF-1α and downstream VEGF. This capillary leakage led to a high accumulation of cisplatin in the perivascular space in SV, and disrupted the integrity of blood-labyrinth barrier (BLB). Also, tight junction (ZO-1) loosening and Na+, K+-ATPase damage was considered to be other critical contributors of BLB breakdown, which resulted in EP drop and consequent hearing loss. This study explored the role of stria vascularis in cisplatin-induced ototoxicity in terms of BLB hyperpermeability and pointed to a novel therapeutic target for the prevention of cisplatin-related hearing loss.
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Bhatt IS, Dias R, Torkamani A. Association Analysis of Candidate Gene Polymorphisms and Tinnitus in Young Musicians. Otol Neurotol 2021; 42:e1203-e1212. [PMID: 34282101 PMCID: PMC10860185 DOI: 10.1097/mao.0000000000003279] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Subjective tinnitus, a perception of phantom sound, is a common otological condition that affects almost 15% of the general population. It is known that noise-induced hearing loss (NIHL) and tinnitus exhibit a high level of comorbidity in individuals exposed to intense noise and music. However, the influence of genetic variants associated with NIHL on tinnitus remains elusive. We hypothesized that young musicians carrying genetic variants associated with NIHL would exhibit a higher prevalence of tinnitus than their counterparts. METHODS To test this hypothesis, we analyzed the database by Bhatt et al. (2020) (originally developed by Phillips et al., 2015) that investigated the genetic links to NIHL in young college-aged musicians. The present study identified 186 participants (average age = 20.3 yrs, range = 18-25 yrs) with normal tympanometry and otoscopic findings and with no missing data. We included 19 single nucleotide polymorphisms in 13 cochlear genes that were previously associated with NIHL. The candidate genes include: KCNE1, KCNQ1, CDH23, GJB2, GJB4, KCNJ10, CAT, HSP70, PCDH70, MYH14, GRM7, PON2, and ESRRB. RESULTS We find that individuals with at least one minor allele of rs163171 (C > T) in KCNQ1 exhibit significantly higher odds of reporting tinnitus compared to individuals carrying the major allele of rs163171. KCNE1 rs2070358 revealed a suggestive association (p = 0.049) with tinnitus, but the FDR corrected p-value did not achieve statistical significance (p < 0.05). A history of ear infection and sound level tolerance showed a statistically significant association with tinnitus. Music exposure showed a suggestive association trend with tinnitus. Biological sex revealed a statistically significant association with distortion product otoacoustic emissions SNR measures. CONCLUSIONS We concluded that KCNQ1/KCNE1 voltage-gated potassium ion channel plays a critical role in the pathogenesis of NIHL and tinnitus. Further research is required to construct clinical tools for identifying genetically predisposed individuals well before they acquire NIHL and tinnitus.
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Affiliation(s)
| | - Raquel Dias
- Scripps Research Translational Institute
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, California
| | - Ali Torkamani
- Scripps Research Translational Institute
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, California
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Milon B, Shulman ED, So KS, Cederroth CR, Lipford EL, Sperber M, Sellon JB, Sarlus H, Pregernig G, Shuster B, Song Y, Mitra S, Orvis J, Margulies Z, Ogawa Y, Shults C, Depireux DA, Palermo AT, Canlon B, Burns J, Elkon R, Hertzano R. A cell-type-specific atlas of the inner ear transcriptional response to acoustic trauma. Cell Rep 2021; 36:109758. [PMID: 34592158 PMCID: PMC8709734 DOI: 10.1016/j.celrep.2021.109758] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 07/29/2021] [Accepted: 09/03/2021] [Indexed: 01/26/2023] Open
Abstract
Noise-induced hearing loss (NIHL) results from a complex interplay of damage to the sensory cells of the inner ear, dysfunction of its lateral wall, axonal retraction of type 1C spiral ganglion neurons, and activation of the immune response. We use RiboTag and single-cell RNA sequencing to survey the cell-type-specific molecular landscape of the mouse inner ear before and after noise trauma. We identify induction of the transcription factors STAT3 and IRF7 and immune-related genes across all cell-types. Yet, cell-type-specific transcriptomic changes dominate the response. The ATF3/ATF4 stress-response pathway is robustly induced in the type 1A noise-resilient neurons, potassium transport genes are downregulated in the lateral wall, mRNA metabolism genes are downregulated in outer hair cells, and deafness-associated genes are downregulated in most cell types. This transcriptomic resource is available via the Gene Expression Analysis Resource (gEAR; https://umgear.org/NIHL) and provides a blueprint for the rational development of drugs to prevent and treat NIHL.
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Affiliation(s)
- Beatrice Milon
- Department of Otorhinolaryngology Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Eldad D Shulman
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Kathy S So
- Decibel Therapeutics, Boston, MA 02215, USA
| | - Christopher R Cederroth
- Laboratory of Experimental Audiology, Department of Physiology and Pharmacology, Karolinska Institute, 171 77 Stockholm, Sweden; Hearing Sciences, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK
| | - Erika L Lipford
- Department of Otorhinolaryngology Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Michal Sperber
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | | | - Heela Sarlus
- Laboratory of Experimental Audiology, Department of Physiology and Pharmacology, Karolinska Institute, 171 77 Stockholm, Sweden; Applied Immunology & Immunotherapy, Neuroimmunology Unit, Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska University Hospital, 171 77 Stockholm, Sweden
| | | | - Benjamin Shuster
- Department of Otorhinolaryngology Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Yang Song
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Sunayana Mitra
- Department of Otorhinolaryngology Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Joshua Orvis
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Zachary Margulies
- Department of Otorhinolaryngology Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Yoko Ogawa
- Department of Otorhinolaryngology Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Christopher Shults
- Department of Otorhinolaryngology Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | | | | | - Barbara Canlon
- Laboratory of Experimental Audiology, Department of Physiology and Pharmacology, Karolinska Institute, 171 77 Stockholm, Sweden
| | - Joe Burns
- Decibel Therapeutics, Boston, MA 02215, USA
| | - Ran Elkon
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
| | - Ronna Hertzano
- Department of Otorhinolaryngology Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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Taukulis IA, Olszewski RT, Korrapati S, Fernandez KA, Boger ET, Fitzgerald TS, Morell RJ, Cunningham LL, Hoa M. Single-Cell RNA-Seq of Cisplatin-Treated Adult Stria Vascularis Identifies Cell Type-Specific Regulatory Networks and Novel Therapeutic Gene Targets. Front Mol Neurosci 2021; 14:718241. [PMID: 34566577 PMCID: PMC8458580 DOI: 10.3389/fnmol.2021.718241] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 08/17/2021] [Indexed: 11/21/2022] Open
Abstract
The endocochlear potential (EP) generated by the stria vascularis (SV) is necessary for hair cell mechanotransduction in the mammalian cochlea. We sought to create a model of EP dysfunction for the purposes of transcriptional analysis and treatment testing. By administering a single dose of cisplatin, a commonly prescribed cancer treatment drug with ototoxic side effects, to the adult mouse, we acutely disrupt EP generation. By combining these data with single cell RNA-sequencing findings, we identify transcriptional changes induced by cisplatin exposure, and by extension transcriptional changes accompanying EP reduction, in the major cell types of the SV. We use these data to identify gene regulatory networks unique to cisplatin treated SV, as well as the differentially expressed and druggable gene targets within those networks. Our results reconstruct transcriptional responses that occur in gene expression on the cellular level while identifying possible targets for interventions not only in cisplatin ototoxicity but also in EP dysfunction.
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Affiliation(s)
- Ian A. Taukulis
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States
| | - Rafal T. Olszewski
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States
| | - Soumya Korrapati
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States
| | - Katharine A. Fernandez
- Laboratory of Hearing Biology and Therapeutics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States
| | - Erich T. Boger
- Genomics and Computational Biology Core, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States
| | - Tracy S. Fitzgerald
- Mouse Auditory Testing Core Facility, National Institutes of Health, Bethesda, MD, United States
| | - Robert J. Morell
- Genomics and Computational Biology Core, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States
| | - Lisa L. Cunningham
- Laboratory of Hearing Biology and Therapeutics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States
| | - Michael Hoa
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States
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Zhang Q, Ota T, Yoshida T, Ino D, Sato MP, Doi K, Horii A, Nin F, Hibino H. Electrochemical properties of the non-excitable tissue stria vascularis of the mammalian cochlea are sensitive to sounds. J Physiol 2021; 599:4497-4516. [PMID: 34426971 DOI: 10.1113/jp281981] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 08/18/2021] [Indexed: 11/08/2022] Open
Abstract
Excitable cochlear hair cells convert the mechanical energy of sounds into the electrical signals necessary for neurotransmission. The key process is cellular depolarization via K+ entry from K+ -enriched endolymph through hair cells' mechanosensitive channels. Positive 80 mV potential in endolymph accelerates the K+ entry, thereby sensitizing hearing. This potential represents positive extracellular potential within the epithelial-like stria vascularis; the latter potential stems from K+ equilibrium potential (EK ) across the strial membrane. Extra- and intracellular [K+ ] determining EK are likely maintained by continuous unidirectional circulation of K+ through a putative K+ transport pathway containing hair cells and stria. Whether and how the non-excitable tissue stria vascularis responds to acoustic stimuli remains unclear. Therefore, we analysed a cochlear portion for the best frequency, 1 kHz, by theoretical and experimental approaches. We have previously developed a computational model that integrates ion channels and transporters in the stria and hair cells into a circuit and described a circulation current composed of K+ . Here, in this model, mimicking of hair cells' K+ flow induced by a 1 kHz sound modulated the circulation current and affected the strial ion transport mechanisms; the latter effect resulted in monotonically decreasing potential and increasing [K+ ] in the extracellular strial compartment. Similar results were obtained when the stria in acoustically stimulated animals was examined using microelectrodes detecting the potential and [K+ ]. Measured potential dynamics mirrored the EK change. Collectively, because stria vascularis is electrically coupled to hair cells by the circulation current in vivo too, the strial electrochemical properties respond to sounds. KEY POINTS: A highly positive potential of +80 mV in K+ -enriched endolymph in the mammalian cochlea accelerates sound-induced K+ entry into excitable sensory hair cells, a process that triggers hearing. This unique endolymphatic potential represents an EK -based battery for a non-excitable epithelial-like tissue, the stria vascularis. To examine whether and how the stria vascularis responds to sounds, we used our computational model, in which strial channels and transporters are serially connected to those hair cells in a closed-loop circuit, and found that mimicking hair cell excitation by acoustic stimuli resulted in increased extracellular [K+ ] and decreased the battery's potential within the stria. This observation was overall verified by electrophysiological experiments using live guinea pigs. The sensitivity of electrochemical properties of the stria to sounds indicates that this tissue is electrically coupled to hair cells by a radial ionic flow called a circulation current.
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Affiliation(s)
- Qi Zhang
- Division of Glocal Pharmacology, Department of Pharmacology, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan.,Department of Molecular Physiology, Niigata University Graduate School of Medical and Dental Sciences, Asahimachi-dori, Niigata, Japan.,Department of Otolaryngology Head and Neck Surgery, Niigata University Graduate School of Medical and Dental Sciences, Asahimachi-dori, Niigata, Japan
| | - Takeru Ota
- Division of Glocal Pharmacology, Department of Pharmacology, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Takamasa Yoshida
- Department of Otorhinolaryngology, Graduate School of Medical Sciences, Kyushu University, Maidashi, Fukuoka, Japan
| | - Daisuke Ino
- Division of Glocal Pharmacology, Department of Pharmacology, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Mitsuo P Sato
- Department of Otolaryngology, Kindai University Faculty of Medicine, Osaka, Japan
| | - Katsumi Doi
- Department of Otolaryngology, Kindai University Faculty of Medicine, Osaka, Japan
| | - Arata Horii
- Department of Otolaryngology Head and Neck Surgery, Niigata University Graduate School of Medical and Dental Sciences, Asahimachi-dori, Niigata, Japan
| | - Fumiaki Nin
- Department of Physiology, Division of Biological Principles, Graduate School of Medicine, Gifu University, Yanagido, Gifu, Japan
| | - Hiroshi Hibino
- Division of Glocal Pharmacology, Department of Pharmacology, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan.,AMED, AMED-CREST, Osaka, Japan
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34
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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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Abstract
Vestibular hair cells are mechanosensory receptors that are capable of detecting changes in head position and thereby allow animals to maintain their posture and coordinate their movement. Vestibular hair cells are susceptible to ototoxic drugs, aging, and genetic factors that can lead to permanent vestibular dysfunction. Vestibular dysfunction mainly results from the injury of hair cells, which are located in the vestibular sensory epithelium. This review summarizes the mechanisms of different factors causing vestibular hair cell damage and therapeutic strategies to protect vestibular hair cells.
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Affiliation(s)
- Luoying Jiang
- ENT Institute and Department of Otorhinolaryngology, Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Zhiwei Zheng
- ENT Institute and Department of Otorhinolaryngology, Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Yingzi He
- ENT Institute and Department of Otorhinolaryngology, Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200031, China.
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China.
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36
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Badash I, Applegate BE, Oghalai JS. In Vivo Cochlear imaging provides a tool to study endolymphatic hydrops. J Vestib Res 2021; 31:269-276. [PMID: 33136083 DOI: 10.3233/ves-200718] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Exposure to noise trauma, such as that from improvised explosive devices, can lead to sensorineural hearing loss and a reduced quality of life. In order to elucidate the mechanisms underlying noise-induced hearing loss, we have adapted optical coherence tomography (OCT) for real-time cochlear visualization in live mice after blast exposure. We demonstrated that endolymphatic hydrops develops following blast injury, and that this phenomenon may be associated with glutamate excitotoxicity and cochlear synaptopathy. Additionally, osmotic stabilization of endolymphatic hydrops partially rescues cochlear synapses after blast trauma. OCT is thus a valuable research tool for investigating the mechanisms underlying acoustic trauma and dynamic changes in endolymph volume. It may also help with the diagnosis and treatment of human hearing loss and/or vertigo in the near future.
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Affiliation(s)
- Ido Badash
- Caruso Department of Otolaryngology-Head and Neck Surgery, University of Southern California, Los Angeles, CA, USA
| | - Brian E Applegate
- Caruso Department of Otolaryngology-Head and Neck Surgery, University of Southern California, Los Angeles, CA, USA
| | - John S Oghalai
- Caruso Department of Otolaryngology-Head and Neck Surgery, University of Southern California, Los Angeles, CA, USA
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37
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Prayuenyong P, Baguley DM, Kros CJ, Steyger PS. Preferential Cochleotoxicity of Cisplatin. Front Neurosci 2021; 15:695268. [PMID: 34381329 PMCID: PMC8350121 DOI: 10.3389/fnins.2021.695268] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 07/06/2021] [Indexed: 11/26/2022] Open
Abstract
Cisplatin-induced ototoxicity in humans is more predominant in the cochlea than in the vestibule. Neither definite nor substantial vestibular dysfunction after cisplatin treatment has been consistently reported in the current literature. Inner ear hair cells seem to have intrinsic characteristics that make them susceptible to direct exposure to cisplatin. The existing literature suggests, however, that cisplatin might have different patterns of drug trafficking across the blood-labyrinth-barrier, or different degrees of cisplatin uptake to the hair cells in the cochlear and vestibular compartments. This review proposes an explanation for the preferential cochleotoxicity of cisplatin based on current evidence as well as the anatomy and physiology of the inner ear. The endocochlear potential, generated by the stria vascularis, acting as the driving force for hair cell mechanoelectrical transduction might also augment cisplatin entry into cochlear hair cells. Better understanding of the stria vascularis might shed new light on cochleotoxic mechanisms and inform the development of otoprotective interventions to moderate cisplatin associated ototoxicity.
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Affiliation(s)
- Pattarawadee Prayuenyong
- Department of Otorhinolaryngology, Head and Neck Surgery, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand.,Hearing Sciences, Division of Clinical Neurosciences, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - David M Baguley
- Hearing Sciences, Division of Clinical Neurosciences, School of Medicine, University of Nottingham, Nottingham, United Kingdom.,National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham, United Kingdom.,Nottingham Audiology Services, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom
| | - Corné J Kros
- School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Peter S Steyger
- Translational Hearing Center, Biomedical Sciences, Creighton University, Omaha, NE, United States
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Jennings SG. The role of the medial olivocochlear reflex in psychophysical masking and intensity resolution in humans: a review. J Neurophysiol 2021; 125:2279-2308. [PMID: 33909513 PMCID: PMC8285664 DOI: 10.1152/jn.00672.2020] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 03/16/2021] [Accepted: 04/02/2021] [Indexed: 02/01/2023] Open
Abstract
This review addresses the putative role of the medial olivocochlear (MOC) reflex in psychophysical masking and intensity resolution in humans. A framework for interpreting psychophysical results in terms of the expected influence of the MOC reflex is introduced. This framework is used to review the effects of a precursor or contralateral acoustic stimulation on 1) simultaneous masking of brief tones, 2) behavioral estimates of cochlear gain and frequency resolution in forward masking, 3) the buildup and decay of forward masking, and 4) measures of intensity resolution. Support, or lack thereof, for a role of the MOC reflex in psychophysical perception is discussed in terms of studies on estimates of MOC strength from otoacoustic emissions and the effects of resection of the olivocochlear bundle in patients with vestibular neurectomy. Novel, innovative approaches are needed to resolve the dissatisfying conclusion that current results are unable to definitively confirm or refute the role of the MOC reflex in masking and intensity resolution.
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Affiliation(s)
- Skyler G Jennings
- Department of Communication Sciences and Disorders, The University of Utah, Salt Lake City, Utah
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39
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Olson A, Zhang F, Cao H, Baranova A, Slavin M. In silico Gene Set and Pathway Enrichment Analyses Highlight Involvement of Ion Transport in Cholinergic Pathways in Autism: Rationale for Nutritional Intervention. Front Neurosci 2021; 15:648410. [PMID: 33958984 PMCID: PMC8093449 DOI: 10.3389/fnins.2021.648410] [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: 12/31/2020] [Accepted: 03/22/2021] [Indexed: 12/12/2022] Open
Abstract
Food is the primary human source of choline, an essential precursor to the neurotransmitter acetylcholine, which has a central role in signaling pathways that govern sensorimotor functions. Most Americans do not consume their recommended amount of dietary choline, and populations with neurodevelopmental conditions like autism spectrum disorder (ASD) may be particularly vulnerable to consequences of choline deficiency. This study aimed to identify a relationship between ASD and cholinergic signaling through gene set enrichment analysis and interrogation of existing database evidence to produce a systems biology model. In gene set enrichment analysis, two gene ontologies were identified as overlapping for autism-related and for cholinergic pathways-related functions, both involving ion transport regulation. Subsequent modeling of ion transport intensive cholinergic signaling pathways highlighted the importance of two genes with autism-associated variants: GABBR1, which codes for the gamma aminobutyric acid receptor (GABAB 1), and KCNN2, which codes for calcium-activated, potassium ion transporting SK2 channels responsible for membrane repolarization after cholinergic binding/signal transmission events. Cholinergic signal transmission pathways related to these proteins were examined in the Pathway Studio environment. The ion transport ontological associations indicated feasibility of a dietary choline support as a low-risk therapeutic intervention capable of modulating cholinergic sensory signaling in autism. Further research at the intersection of dietary status and sensory function in autism is warranted.
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Affiliation(s)
- Audrey Olson
- Department of Nutrition and Food Studies, College of Health and Human Services, George Mason University, Fairfax, VA, United States
- School of Systems Biology, College of Science, George Mason University, Manassas, VA, United States
| | - Fuquan Zhang
- Department of Psychiatry, Nanjing Medical University, Nanjing, China
| | - Hongbao Cao
- School of Systems Biology, College of Science, George Mason University, Manassas, VA, United States
- Department of Psychiatry, Shanxi Medical University, Taiyuan, China
| | - Ancha Baranova
- School of Systems Biology, College of Science, George Mason University, Manassas, VA, United States
- Research Centre for Medical Genetics, Moscow, Russia
| | - Margaret Slavin
- Department of Nutrition and Food Studies, College of Health and Human Services, George Mason University, Fairfax, VA, United States
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Association Analysis of Candidate Gene Polymorphisms and Audiometric Measures of Noise-Induced Hearing Loss in Young Musicians. Otol Neurotol 2021; 41:e538-e547. [PMID: 32176153 DOI: 10.1097/mao.0000000000002615] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
INTRODUCTION This study aimed to investigate the association between candidate genetic variants and audiometric measures of noise-induced hearing loss (NIHL) in young musicians. METHODS The study analyzed a database by Phillips et al. (Feasibility of a bilateral 4000-6000 Hz notch as a phenotype for genetic association analysis. Int J Audiol 2015;54:645-52.) which included behavioral hearing thresholds, distortion-product otoacoustic emissions (DPOAE), tympanometric, and genetic data of 166 participants meeting the inclusion criteria. Nineteen single nucleotide polymorphisms (SNPs) in 13 cochlear genes previously associated with NIHL in factory workers were included in the present investigation. The average hearing threshold at 3000 and 4000 Hz (AHT) and average DPOAE signal to noise ratio (DPOAE SNR) in both ears were calculated. RESULTS The regression analyses showed that two SNPs- one in KCNE1 (rs2070358) and the other in CAT (rs12273124) revealed a statistically significant relationship with DPOAE SNR in both ears. Two SNPs in MYH14 and one in GJB4 revealed a significant association with DPOAE SNR in the left ear. Two SNPs in HSP70, one in CDH23 and one in KCNJ10 showed significant association with DPOAE SNR in the right ear. None of the included SNPs showed association with AHT in both ears. CONCLUSIONS A genetic variant in KCNE1 was associated with the strength of the cochlear amplifier as assessed by DPOAE SNR. Musicians carrying causal genetic variants to NIHL might exhibit changes in their auditory functions early in the lifespan even when most subjects had their hearing thresholds within normal limits. These participants are likely to show the clinical manifestation of NIHL in the future if no preventive measures are applied.
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Eckert MA, Harris KC, Lang H, Lewis MA, Schmiedt RA, Schulte BA, Steel KP, Vaden KI, Dubno JR. Translational and interdisciplinary insights into presbyacusis: A multidimensional disease. Hear Res 2021; 402:108109. [PMID: 33189490 PMCID: PMC7927149 DOI: 10.1016/j.heares.2020.108109] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 10/19/2020] [Accepted: 10/25/2020] [Indexed: 12/18/2022]
Abstract
There are multiple etiologies and phenotypes of age-related hearing loss or presbyacusis. In this review we summarize findings from animal and human studies of presbyacusis, including those that provide the theoretical framework for distinct metabolic, sensory, and neural presbyacusis phenotypes. A key finding in quiet-aged animals is a decline in the endocochlear potential (EP) that results in elevated pure-tone thresholds across frequencies with greater losses at higher frequencies. In contrast, sensory presbyacusis appears to derive, in part, from acute and cumulative effects on hair cells of a lifetime of environmental exposures (e.g., noise), which often result in pronounced high frequency hearing loss. These patterns of hearing loss in animals are recognizable in the human audiogram and can be classified into metabolic and sensory presbyacusis phenotypes, as well as a mixed metabolic+sensory phenotype. However, the audiogram does not fully characterize age-related changes in auditory function. Along with the effects of peripheral auditory system declines on the auditory nerve, primary degeneration in the spiral ganglion also appears to contribute to central auditory system aging. These inner ear alterations often correlate with structural and functional changes throughout the central nervous system and may explain suprathreshold speech communication difficulties in older adults with hearing loss. Throughout this review we highlight potential methods and research directions, with the goal of advancing our understanding, prevention, diagnosis, and treatment of presbyacusis.
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Affiliation(s)
- Mark A Eckert
- Medical University of South Carolina, Department of Otolaryngology - Head and Neck Surgery, Charleston, SC 29425, USA.
| | - Kelly C Harris
- Medical University of South Carolina, Department of Otolaryngology - Head and Neck Surgery, Charleston, SC 29425, USA
| | - Hainan Lang
- Medical University of South Carolina, Department of Pathology and Laboratory Medicine, Charleston, SC 29425, USA
| | - Morag A Lewis
- King's College London, Wolfson Centre for Age-Related Diseases, London SE1 1UL, United Kingdom
| | - Richard A Schmiedt
- Medical University of South Carolina, Department of Otolaryngology - Head and Neck Surgery, Charleston, SC 29425, USA
| | - Bradley A Schulte
- Medical University of South Carolina, Department of Pathology and Laboratory Medicine, Charleston, SC 29425, USA; Medical University of South Carolina, Department of Otolaryngology - Head and Neck Surgery, Charleston, SC 29425, USA
| | - Karen P Steel
- King's College London, Wolfson Centre for Age-Related Diseases, London SE1 1UL, United Kingdom
| | - Kenneth I Vaden
- Medical University of South Carolina, Department of Otolaryngology - Head and Neck Surgery, Charleston, SC 29425, USA
| | - Judy R Dubno
- Medical University of South Carolina, Department of Otolaryngology - Head and Neck Surgery, Charleston, SC 29425, USA; Medical University of South Carolina, Department of Pathology and Laboratory Medicine, Charleston, SC 29425, USA
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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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Liu Y, Chu HQ, Sun YB, Bing D, Zhou LQ, Chen J, Chen QG, Du ZH. Expression of α2-Na/K-ATPase in C57BL/6J Mice Inner Ear and Its Relationship with Age-related Hearing Loss. Curr Med Sci 2021; 41:153-157. [PMID: 33582920 DOI: 10.1007/s11596-021-2330-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 12/01/2020] [Indexed: 11/25/2022]
Abstract
K+ cycling in the cochlea is critical to maintain hearing. Many sodium-potassium pumps are proved to participate in K+ cycling, such as Na/K-ATPase. The α2-Na/K-ATPase is an important isoform of Na/K-ATPase. The expression of α2-Na/K-ATPase in the cochlea is not clear. In this study, we used C57BL/6 mice as a model of presbycusis and implemented immunohistochemistry staining and quantitative real time-PCR, and the α2-Na/K-ATPase expression pattern was confirmed in the inner ear. It was found α2-Na/K-ATPase was expressed widely in cochlea and its mRNA and protein expression was gradually reduced with aging (4-, 14-, 26- and 48-weeks old mice). We suspected that, the down-regulation of α2-Na/K-ATPase expression might be associated with the remodeling of K+ cycling, degeneration of morphological structure and decrease of hearing function in aging C57 mice. In conclusion, we speculated that the reduction of α2-Na/K-ATPase might play an important role in the pathogenesis of age-related hearing loss.
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Affiliation(s)
- Yun Liu
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Han-Qi Chu
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
| | - Yan-Bo Sun
- Department of Otolaryngology-Head and Neck Surgery, the Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Dan Bing
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Liang-Qiang Zhou
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Jin Chen
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Qing-Guo Chen
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Zhi-Hui Du
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
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Wu M, Xia M, Li W, Li H. Single-Cell Sequencing Applications in the Inner Ear. Front Cell Dev Biol 2021; 9:637779. [PMID: 33644075 PMCID: PMC7907461 DOI: 10.3389/fcell.2021.637779] [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: 12/04/2020] [Accepted: 01/21/2021] [Indexed: 01/29/2023] Open
Abstract
Genomics studies face specific challenges in the inner ear due to the multiple types and limited amounts of inner ear cells that are arranged in a very delicate structure. However, advances in single-cell sequencing (SCS) technology have made it possible to analyze gene expression variations across different cell types as well as within specific cell groups that were previously considered to be homogeneous. In this review, we summarize recent advances in inner ear research brought about by the use of SCS that have delineated tissue heterogeneity, identified unknown cell subtypes, discovered novel cell markers, and revealed dynamic signaling pathways during development. SCS opens up new avenues for inner ear research, and the potential of the technology is only beginning to be explored.
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Affiliation(s)
- Mingxuan Wu
- ENT Institute and Department of Otorhinolaryngology, Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
| | - Mingyu Xia
- ENT Institute and Department of Otorhinolaryngology, Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
| | - Wenyan Li
- ENT Institute and Department of Otorhinolaryngology, Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
| | - Huawei Li
- ENT Institute and Department of Otorhinolaryngology, Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China.,Institutes of Biomedical Sciences, Fudan University, Shanghai, China.,NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, China.,The Institutes of Brain Science and The Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, China
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Gu S, Olszewski R, Nelson L, Gallego-Martinez A, Lopez-Escamez JA, Hoa M. Identification of Potential Meniere's Disease Targets in the Adult Stria Vascularis. Front Neurol 2021; 12:630561. [PMID: 33613436 PMCID: PMC7894210 DOI: 10.3389/fneur.2021.630561] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 01/12/2021] [Indexed: 12/13/2022] Open
Abstract
The stria vascularis generates the endocochlear potential and is involved in processes that underlie ionic homeostasis in the cochlear endolymph, both which play essential roles in hearing. The histological hallmark of Meniere's disease (MD) is endolymphatic hydrops, which refers to the bulging or expansion of the scala media, which is the endolymph-containing compartment of the cochlea. This histologic hallmark suggests that processes that disrupt ion homeostasis or potentially endocochlear potential may underlie MD. While treatments exist for vestibular symptoms related to MD, effective therapies for hearing fluctuation and hearing loss seen in MD remain elusive. Understanding the potential cell types involved in MD may inform the creation of disease mouse models and provide insight into underlying mechanisms and potential therapeutic targets. For these reasons, we compare published datasets related to MD in humans with our previously published adult mouse stria vascularis single-cell and single-nucleus RNA-Seq datasets to implicate potentially involved stria vascularis (SV) cell types in MD. Finally, we provide support for these implicated cell types by demonstrating co-expression of select candidate genes for MD within SV cell types.
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Affiliation(s)
- Shoujun Gu
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Rafal Olszewski
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Lacey Nelson
- Department of Otolaryngology-Head and Neck Surgery, Georgetown University School of Medicine, Washington, DC, United States
| | - Alvaro Gallego-Martinez
- Otology and Neurotology Group CTS495, Department of Genomic Medicine, Centre for Genomics and Oncological Research, Pfizer/Universidad de Granada/Junta de Andalucía (GENYO), Granada, Spain
| | - Jose Antonio Lopez-Escamez
- Otology and Neurotology Group CTS495, Department of Genomic Medicine, Centre for Genomics and Oncological Research, Pfizer/Universidad de Granada/Junta de Andalucía (GENYO), Granada, Spain
- Department of Otolaryngology, Instituto de Investigación Biosanitaria ibs.GRANADA, Hospital Universitario Virgen de las Nieves, Granada, Spain
- Division of Otolaryngology, Department of Surgery, University of Granada, Granada, Spain
| | - Michael Hoa
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health (NIH), Bethesda, MD, United States
- Department of Otolaryngology-Head and Neck Surgery, Georgetown University School of Medicine, Washington, DC, United States
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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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van Beelen ESA, van der Valk WH, de Groot JCMJ, Hensen EF, Locher H, van Benthem PPG. Migration and fate of vestibular melanocytes during the development of the human inner ear. Dev Neurobiol 2020; 80:411-432. [PMID: 33075185 PMCID: PMC7894185 DOI: 10.1002/dneu.22786] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 10/12/2020] [Accepted: 10/12/2020] [Indexed: 12/19/2022]
Abstract
Melanocytes are present in various parts of the inner ear, including the stria vascularis in the cochlea and the dark cell areas in the vestibular organs, where they contribute to endolymph homeostasis. Developmental studies describing the distribution of vestibular melanocytes are scarce, especially in humans. In this study, we investigated the distribution and maturation of the vestibular melanocytes in relation to the developing dark cell epithelium in inner ear specimens from week 5 to week 14 of development and in surgical specimens of the adult ampulla. Vestibular melanocytes were located around the utricle and the ampullae of the semicircular canals before week 7 and were first seen underneath the transitional zones and dark cell areas between week 8 and week 10. At week 10, melanocytes made intimate contact with epithelial cells, interrupting the local basement membrane with their dendritic processes. At week 11, most melanocytes were positioned under the dark cell epithelia. No melanocytes were seen around or in the saccule during all investigated developmental stages. The dark cell areas gradually matured and showed an adult immunohistochemical profile of the characteristic ion transporter protein Na+/K+‐ATPase α1 by week 14. Furthermore, we investigated the expression of the migration‐related proteins ECAD, PCAD, KIT, and KITLG in melanocytes and dark cell epithelium. This is the first study to describe the spatiotemporal distribution of vestibular melanocytes during the human development and thereby contributes to understanding normal vestibular function and pathophysiological mechanisms underlying vestibular disorders.
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Affiliation(s)
- Edward S A van Beelen
- Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, Leiden, the Netherlands
| | - Wouter H van der Valk
- Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, Leiden, the Netherlands
| | - John C M J de Groot
- Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, Leiden, the Netherlands
| | - Erik F Hensen
- Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, Leiden, the Netherlands
| | - Heiko Locher
- Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, Leiden, the Netherlands
| | - Peter Paul G van Benthem
- Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, Leiden, the Netherlands
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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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Cisplatin-Induced Stria Vascularis Damage Is Associated with Inflammation and Fibrosis. Neural Plast 2020; 2020:8851525. [PMID: 33029120 PMCID: PMC7527906 DOI: 10.1155/2020/8851525] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 08/05/2020] [Accepted: 09/03/2020] [Indexed: 12/20/2022] Open
Abstract
The stria vascularis (SV) generates the endocochlear potential (EP) in the inner ear and is necessary for proper hair cell (HC) mechanotransduction and hearing. Cell junctions are indispensable for the establishment of compositionally distinct fluid compartments in the inner ear. Ototoxic drug cisplatin can damage SV and cause sensorineural hearing loss; however, the underlying mechanisms behind such injury are unclear. In this study, after the intraperitoneal injection of cisplatin (3 mg/kg/day for 7 days) in mice, we determined the auditory function by EP recording and auditory brainstem response (ABR) analysis, observed the ultrastructure of SV by transmission electron microscopy (TEM), and examined the expression and distribution of cell junction proteins by western blot, PCR, and immunofluorescence staining. We discovered that the EP was significantly reduced while ABR thresholds were significantly elevated in cisplatin-treated mice; cisplatin induced ultrastructural changes in marginal cells (MCs), endothelial cells (ECs), pericytes, etc. We found that cisplatin insulted auditory function not only by reducing the expression of zonula occludens protein-1 (ZO-1) in MCs of the SV but also by decreasing the expression of connexin 26 (Cx26) and connexin 43 (Cx43) in MCs and basal cells (BCs). More importantly, cisplatin induced activations of perivascular-resident macrophage-like melanocytes (PVM/Ms) and interleukin-1beta (IL-1β) as well as increased expressions of profibrotic proteins such as laminin and collagen IV in SV. Thus, our results firstly showed that cisplatin induced fibrosis, inflammation, and the complex expression change of cell junctions in SV.
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Askew C, Chien WW. Adeno-associated virus gene replacement for recessive inner ear dysfunction: Progress and challenges. Hear Res 2020; 394:107947. [PMID: 32247629 PMCID: PMC7939749 DOI: 10.1016/j.heares.2020.107947] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 03/02/2020] [Accepted: 03/04/2020] [Indexed: 01/08/2023]
Abstract
Approximately 3 in 1000 children in the US under 4 years of age are affected by hearing loss. Currently, cochlear implants represent the only line of treatment for patients with severe to profound hearing loss, and there are no targeted drug or biological based therapies available. Gene replacement is a promising therapeutic approach for hereditary hearing loss, where viral vectors are used to deliver functional cDNA to "replace" defective genes in dysfunctional cells in the inner ear. Proof-of-concept studies have successfully used this approach to improve auditory function in mouse models of hereditary hearing loss, and human clinical trials are on the immediate horizon. The success of this method is ultimately determined by the underlying biology of the defective gene and design of the treatment strategy, relying on intervention before degeneration of the sensory structures occurs. A challenge will be the delivery of a corrective gene to the proper target within the therapeutic window of opportunity, which may be unique for each specific defective gene. Although rescue of pre-lingual forms of recessive deafness have been explored in animal models thus far, future identification of genes with post-lingual onset that are amenable to gene replacement holds even greater promise for treatment, since the therapeutic window is likely open for a much longer period of time. This review summarizes the current state of adeno-associated virus (AAV) gene replacement therapy for recessive hereditary hearing loss and discusses potential challenges and opportunities for translating inner ear gene replacement therapy for patients with hereditary hearing loss.
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Affiliation(s)
- Charles Askew
- Gene Therapy Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Wade W Chien
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, Bethesda, MD, USA; Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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