1
|
Ichikawa R, Takeda T, Kakigi A, Ito H, Kobayashi T, Hyodo M. Expression of AQP-10, -11 and -12 in the rat stria vascularis. Acta Otolaryngol 2024; 144:96-99. [PMID: 38511591 DOI: 10.1080/00016489.2024.2329286] [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: 02/21/2024] [Accepted: 03/06/2024] [Indexed: 03/22/2024]
Abstract
BACKGROUND Water homeostasis is essential for inner ear function. Several aquaporins (AQPs), which are water transport proteins in the cell or plasma membrane, have been reported in the lateral wall of the rat inner ear (cochlea). However, the presence of AQP-10, -11 and -12 has not been reported in the rat stria vascularis (SV) to date. AIMS/OBJECTIVES We have aimed to clarify the expression of AQP-10, -11 and -12 in the cochlea lateral wall. MATERIALS AND METHODS Using Wistar rats, we examined the expression of AQP-10, -11 and -12 in the cochlea lateral wall using molecular approaches and immunohistochemistry. RESULTS AQP-11 was molecular biologically expressed, but the expression of AQP-10 and -12 was not observed. Immunohistochemically, AQP-11 was diffusely localized in the basal cells and marginal cells of the rat SV but was not expressed at the apical site of marginal cells with double staining. The expression of AQP-10 and -12 was not observed. CONCLUSIONS AND SIGNIFICANCE Only AQP-11 was expressed in the basal cells and marginal cells, but it was not expressed at the apical site of marginal cells. Based on this study, AQP-11 may not have an important role in water flux between the perilymph and endolymph.
Collapse
Affiliation(s)
- Rie Ichikawa
- Department of Otolaryngology, Kochi Medical School, Nankoku, Japan
- Department of Otolaryngology, Niyodo Hospital, Ino, Japan
| | - Taizo Takeda
- Department of Otolaryngology, Kochi Medical School, Nankoku, Japan
| | - Akinobu Kakigi
- Department of Otolaryngology-Head & Neck Surgery, Graduate School of Medicine, Kobe University, Kobe, Japan
| | - Hiroaki Ito
- Department of Otolaryngology, Kochi Medical School, Nankoku, Japan
| | | | - Masamitsu Hyodo
- Department of Otolaryngology, Kochi Medical School, Nankoku, Japan
| |
Collapse
|
2
|
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.
Collapse
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
| |
Collapse
|
3
|
The role of Aquaporins in Hearing Function and Dysfunction. Eur J Cell Biol 2022; 101:151252. [DOI: 10.1016/j.ejcb.2022.151252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/09/2022] [Accepted: 06/22/2022] [Indexed: 11/23/2022] Open
|
4
|
The role of mammalian superaquaporins inside the cell: An update. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183617. [PMID: 33811846 DOI: 10.1016/j.bbamem.2021.183617] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 12/20/2022]
Abstract
The progress on mammalian superaquaporin (sAQP), AQP11 and AQP12, in the past seven years is brought up to date from the previous review. This subfamily is separated because of the very low homology with other AQP subfamilies and it is present only in multicellular organisms excluding fungi and plants. Its unique intracellular localization, specifically in the ER has made its functional studies challenging, but it may function as glyceroporin, aquaporin and peroxiporin, H2O2 transporter. Knowledge on AQP11 has been expanded by tissue specific conditional knockout mice and by the identification of a SNP associated with kidney diseases. Moreover, the functional identification of AQP11 as a peroxiporin has expanded the role of AQP11 to the regulation of intracellular H2O2 homeostasis to prevent ER stress, which awaits further in vivo studies. As kidney-specific AQP11 knockout of developed kidney has produced little phenotype, AQP11 is critical for kidney development but its physiological significance remains to be clarified. On the other hand, little has been known on pancreas-specific AQP12. To move this field forward, the results of sAQP in lower animals will be necessary to obtain the insights into the role of mammalian sAQP, which hopefully will lead to the discovery of therapeutic targets.
Collapse
|
5
|
Moss FJ, Mahinthichaichan P, Lodowski DT, Kowatz T, Tajkhorshid E, Engel A, Boron WF, Vahedi-Faridi A. Aquaporin-7: A Dynamic Aquaglyceroporin With Greater Water and Glycerol Permeability Than Its Bacterial Homolog GlpF. Front Physiol 2020; 11:728. [PMID: 32695023 PMCID: PMC7339978 DOI: 10.3389/fphys.2020.00728] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Accepted: 06/04/2020] [Indexed: 12/27/2022] Open
Abstract
Xenopus oocytes expressing human aquaporin-7 (AQP7) exhibit greater osmotic water permeability and 3H-glycerol uptake vs. those expressing the bacterial glycerol facilitator GlpF. AQP7-expressing oocytes exposed to increasing extracellular [glycerol] under isosmolal conditions exhibit increasing swelling rates, whereas GlpF-expressing oocytes do not swell at all. To provide a structural basis for these observed physiological differences, we performed X-ray crystallographic structure determination of AQP7 and molecular-dynamics simulations on AQP7 and GlpF. The structure reveals AQP7 tetramers containing two monomers with 3 glycerols, and two monomers with 2 glycerols in the pore. In contrast to GlpF, no glycerol is bound at the AQP7 selectivity filter (SF), comprising residues F74, G222, Y223, and R229. The AQP7 SF is resolved in its closed state because F74 blocks the passage of small solutes. Molecular dynamics simulations demonstrate that F74 undergoes large and rapid conformational changes, allowing glycerol molecules to permeate without orientational restriction. The more rigid GlpF imposes orientational constraints on glycerol molecules passing through the SF. Moreover, GlpF-W48 (analogous to AQP7-F74) undergoes rare but long-lasting conformational changes that block the pore to H2O and glycerol.
Collapse
Affiliation(s)
- Fraser J. Moss
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Paween Mahinthichaichan
- Department of Biochemistry, Center for Biophysics and Quantitative Biology, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - David T. Lodowski
- Department of Nutrition, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Thomas Kowatz
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Emad Tajkhorshid
- Department of Biochemistry, Center for Biophysics and Quantitative Biology, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Andreas Engel
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Walter F. Boron
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
- Department of Medicine, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
- Department of Biochemistry, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Ardeschir Vahedi-Faridi
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
| |
Collapse
|
6
|
Dong SH, Kim SS, Kim SH, Yeo SG. Expression of aquaporins in inner ear disease. Laryngoscope 2019; 130:1532-1539. [PMID: 31593306 DOI: 10.1002/lary.28334] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 09/05/2019] [Accepted: 09/10/2019] [Indexed: 12/22/2022]
Abstract
The inner ear is responsible for hearing and balance and consists of a membranous labyrinth within a bony labyrinth. The balance structure is divided into the otolith organ that recognizes linear acceleration and the semicircular canal that is responsible for rotational movement. The cochlea is the hearing organ. The external and middle ear are covered with skin and mucosa, respectively, and the space is filled with air, whereas the inner ear is composed of endolymph and perilymph. The inner ear is a fluid-filled sensory organ composed of hair cells with cilia on the upper part of the cells that convert changes in sound energy and balance into electric energy through the hair cells to transmit signals to the auditory nerve through synapses. Aquaporins (AQPs) are a family of transmembrane proteins present in all species that can be roughly divided into three subfamilies according to structure and function: 1) classical AQP, 2) aquaglyceroporin, and 3) superaquaporin. Currently, the subfamily of mammalian species is known to include 13 AQP members (AQP0-AQP12). AQPs have a variety of functions depending on their structure and are related to inner ear diseases such as Meniere's disease, sensorineural hearing loss, and presbycusis. Additional studies on the relationship between the inner ear and AQPs may be helpful in the diagnosis and treatment of inner ear disease. Laryngoscope, 130:1532-1539, 2020.
Collapse
Affiliation(s)
- Sung Hwa Dong
- Department of Otorhinolaryngology-Head and Neck Surgery, Graduate School, Kyung Hee University, Seoul, South Korea
| | - Sung Su Kim
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul, South Korea
| | - Sang Hoon Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Graduate School, Kyung Hee University, Seoul, South Korea
| | - Seung Geun Yeo
- Department of Otorhinolaryngology-Head and Neck Surgery, Graduate School, Kyung Hee University, Seoul, South Korea.,Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul, South Korea
| |
Collapse
|
7
|
Correlations Between the Degree of Endolymphatic Hydrops and Symptoms and Audiological Test Results in Patients With Menière's Disease: A Reevaluation. Otol Neurotol 2019; 39:351-356. [PMID: 29287037 DOI: 10.1097/mao.0000000000001675] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE This study was performed to reevaluate the diagnostic significance of clinically well-accepted audiological tests in indicating endolymphatic hydrops (EH) in Menière's disease (MD). STUDY DESIGN Retrospective case review. SETTINGS Hospital. PATIENTS Fifty patients (52 affected ears) diagnosed with MD were enrolled. INTERVENTION Diagnostic. MAIN OUTCOME MEASURE To analyze the correlations between endolymphatic hydrops and results of audiological test including the pure-tone audiometry threshold, suprathreshold function tests, electrocochleogram, and glycerol test. RESULTS Three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging demonstrated EH in either the vestibule or cochlea to various degrees in all of the MD patients, 24 hours after intratympanic gadolinium chelate injection. Both vestibular and cochlear EH were significantly correlated with PTA threshold. However, EH was not associated with alternate binaural loudness balance or the tone decay test, although a correlation was observed with the short-increment sensitivity index. There was also a correlation between vestibular EH, but not cochlear EH, and the negative summating potential/action potential (-SP/AP) ratio. Neither vestibular EH nor cochlear EH was correlated with the glycerol test results. In addition, the frequency of vertigo attacks, the existence of tinnitus, and aural fullness did not correlate with EH. CONCLUSIONS Disrupted ionic homeostasis in the inner ear, but not the EH, may contribute to changes in the -SP/AP ratio. The relevance of glycerol test in identifying EH through detection of hearing changes needs further investigation in the future.
Collapse
|
8
|
Liu JY, Chen XX, Chen HY, Shi J, Leung GPH, Tang SCW, Lao LX, Yip HKF, Lee KF, Sze SCW, Zhang ZJ, Zhang KY. Downregulation of Aquaporin 9 Exacerbates Beta-amyloid-induced Neurotoxicity in Alzheimer’s Disease Models In vitro and In vivo. Neuroscience 2018; 394:72-82. [DOI: 10.1016/j.neuroscience.2018.09.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Revised: 09/12/2018] [Accepted: 09/17/2018] [Indexed: 11/16/2022]
|
9
|
Li X, Ohgami N, Omata Y, Yajima I, Iida M, Oshino R, Ohnuma S, Ahsan N, Akhand AA, Kato M. Oral exposure to arsenic causes hearing loss in young people aged 12-29 years and in young mice. Sci Rep 2017; 7:6844. [PMID: 28754998 PMCID: PMC5533757 DOI: 10.1038/s41598-017-06096-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 06/07/2017] [Indexed: 11/16/2022] Open
Abstract
There is no information on the association between oral exposure to arsenic (As) and hearing loss in humans or mice. In this combined epidemiological study and experimental study, the association of oral exposure to As with hearing loss in people aged 12–29 years and young mice was examined. Subjects in the exposure group (n = 48), who were drinking tube well water contaminated with As, showed significantly higher risks of hearing loss at 4 kHz [odds ratio (OR) = 7.60; 95% confidence interval (CI): 1.56, 57.88], 8 kHz (OR = 5.00; 95% CI: 1.48, 18.90) and 12 kHz (OR = 8.72; 95% CI: 2.09, 47.77) than did subjects in the control group (n = 29). We next performed an experiment in which young mice were exposed to As via drinking water at 22.5 mg/L, which is a much greater concentration than that in human studies. The exposure group showed hearing loss and accumulation of As in inner ears. Ex vivo exposure of the organ of Corti from mice exposed to As significantly decreased the number of auditory neurons and fibers. Thus, our combined study showed that oral exposure to As caused hearing loss in young people and young mice.
Collapse
Affiliation(s)
- Xiang Li
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Nobutaka Ohgami
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Nutritional Health Science Research Center, Chubu University, 1200 Matsumoto, Kasugai, 487-8501, Aichi, Japan.,Voluntary Body for International Health Care in Universities, Nagoya, Japan
| | - Yasuhiro Omata
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Ichiro Yajima
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Voluntary Body for International Health Care in Universities, Nagoya, Japan
| | - Machiko Iida
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Nutritional Health Science Research Center, Chubu University, 1200 Matsumoto, Kasugai, 487-8501, Aichi, Japan
| | - Reina Oshino
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Voluntary Body for International Health Care in Universities, Nagoya, Japan
| | - Shoko Ohnuma
- Voluntary Body for International Health Care in Universities, Nagoya, Japan
| | - Nazmul Ahsan
- Voluntary Body for International Health Care in Universities, Nagoya, Japan.,Department of Genetic Engineering and Biotechnology, University of Dhaka, Dhaka, 1000, Bangladesh
| | - Anwarul Azim Akhand
- Voluntary Body for International Health Care in Universities, Nagoya, Japan.,Department of Genetic Engineering and Biotechnology, University of Dhaka, Dhaka, 1000, Bangladesh
| | - Masashi Kato
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan. .,Voluntary Body for International Health Care in Universities, Nagoya, Japan.
| |
Collapse
|