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Huang C, Wang Q, Pan X, Li W, Liu W, Jiang W, Huang L, Peng A, Zhang Z. Up-Regulated Expression of Interferon-Gamma, Interleukin-6 and Tumor Necrosis Factor-Alpha in the Endolymphatic Sac of Meniere's Disease Suggesting the Local Inflammatory Response Underlies the Mechanism of This Disease. Front Neurol 2022; 13:781031. [PMID: 35280304 PMCID: PMC8904419 DOI: 10.3389/fneur.2022.781031] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 01/27/2022] [Indexed: 12/20/2022] Open
Abstract
Background Immune mediated inflammatory changes affecting the endolymphatic sac (ES) may underlie the pathology of Meniere's disease (MD). The aim of the present study was to explore the differentially expressed cytokines in ES luminal fluid (ELF) of patients with MD, and the correlation between the expression of cytokines in the ELF with that in the serum was determined by quantitatively analyzing the cytokines in human ELF and serum. Methods Human ELF, serum and ES tissues were collected from patients with unilateral MD and patients with acoustic neuroma (AN) during surgery. The Simoa Cytokine 6-Plex Panel kit was used to analyze the levels of cytokines in the ELF and blood samples of the patients. Immunohistochemistry and immunofluorescence were subsequently used to validate the relative expression levels of the cytokines in MD. Results Significant differences were identified in the expression levels of interferon-γ (IFN-γ) (P < 0.001), interleukin (IL)-6 (P = 0.008) and tumor necrosis factor-α (TNF-α) (P = 0.036) in the luminal fluid of the ES comparing between the MD and AN groups. By contrast, the levels of IFN-γ, IL-10, IL-12p70, IL-17A, IL-6 and TNF-α in the serum of the MD group were not significantly different from those of either the AN group or healthy control subjects. In addition, no significant correlations in the expression levels of cytokines compared between the ELF and serum were found for the patients in either the MD or the AN group. Finally, the detection of positive expression of TNF-α, IL-6 and IFN-γ in the epithelial cells of the majority of ES specimens from patients with MD confirmed the up-regulated expression of these cytokines in the ES of patients with MD. Conclusions The identification of up-regulated expression levels of TNF-α, IL-6 and IFN-γ in the ELF in the present study has provided direct evidence for an increased immunologic activity in the microenvironment of the ES in patients with unilateral MD, may suggest the local inflammatory response underlies the mechanism of this disease.
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Affiliation(s)
- Chao Huang
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Qin Wang
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Xueying Pan
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Wei Li
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Wei Liu
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Wenqi Jiang
- Department of Anesthesiology, Sun Yat-Sen University Cancer Center, Guangzhou, China
| | - Li Huang
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Anquan Peng
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Zhiwen Zhang
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
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Chabbert C. Pathophysiological mechanisms at the sources of the endolymphatic hydrops, and possible consequences. J Vestib Res 2021; 31:289-295. [PMID: 33579885 DOI: 10.3233/ves-200792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The mechanisms of ion exchanges and water fluxes underlying the endolymphatic hydrops phenomenon, remain indeterminate so far. This review intends to reposition the physical environment of the endolymphatic compartment within the inner ear, as well as to recall the molecular effectors present in the membranous labyrinth and that could be at the source of the hydrops.
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Affiliation(s)
- Christian Chabbert
- Aix Marseille University-CNRS, Laboratory of Cognitive Neurosciences, UMR 7291, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France.,Research Group on Vestibular Pathophysiology Unity GDR#, France
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Kim SH, Nam GS, Choi JY. Pathophysiologic Findings in the Human Endolymphatic Sac in Endolymphatic Hydrops: Functional and Molecular Evidence. Ann Otol Rhinol Laryngol 2019; 128:76S-83S. [PMID: 31092029 DOI: 10.1177/0003489419837993] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The endolymphatic sac (ES) is a cystic structure situated on the posterior fossa dura and is connected to the luminal space of the vestibular organ through the endolymphatic duct, which branches into the utricular and saccular ducts. Unlike the cochlea and vestibule, the ES does not contain sensory epithelium in its luminal space, and a single layer of epithelial cells line the luminal surface area. The ES in the inner ear is thought to play a role in the regulation of inner ear homeostasis, fluid volume, and immune reaction. If these functions of the ES are disrupted, dysfunction of the inner ear may develop. The most well-known pathology arising from dysfunction of the ES is endolymphatic hydrops, characterized by an enlarged endolymphatic space due to the accumulation of excessive endolymphatic fluid. Although, molecular identities and functional evidence for the roles were identified in animal studies, basic studies of the human ES are relatively uncommon compared with those using animal tissues, because of limited opportunity to harvest the human ES. METHODS In this study, molecular and functional evidence for the role of the human ES in the development of endolymphatic hydrops are reviewed. RESULTS AND CONCLUSIONS Although evidence is insufficient, studies using the human ES have mostly produced findings similar to those of animal studies. This review may provide a basis for planning further studies to investigate the pathophysiology of disorders with the finding of endolymphatic hydrops.
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Affiliation(s)
- Sung Huhn Kim
- 1 Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, Republic of Korea.,2 The Airway Mucus Institute, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Gi-Sung Nam
- 1 Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jae Young Choi
- 1 Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, Republic of Korea.,2 The Airway Mucus Institute, Yonsei University College of Medicine, Seoul, Republic of Korea
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Møller MN, Kirkeby S, Vikeså J, Nielsen FC, Cayé-Thomasen P. The human endolymphatic sac expresses natriuretic peptides. Laryngoscope 2017; 127:E201-E208. [DOI: 10.1002/lary.26074] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 04/07/2016] [Accepted: 04/12/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Martin Nue Møller
- Department of Otorhinolaryngology, Head and Neck Surgery; Rigshospitalet; Copenhagen Denmark
| | - Svend Kirkeby
- Department of Oral Medicine, Dental School, Panum Institute; University of Copenhagen; Copenhagen Denmark
| | - Jonas Vikeså
- Center for Genomic Medicine; University of Copenhagen; Rigshospitalet Copenhagen Denmark
| | - Finn Cilius Nielsen
- Center for Genomic Medicine; University of Copenhagen; Rigshospitalet Copenhagen Denmark
| | - Per Cayé-Thomasen
- Department of Otorhinolaryngology, Head and Neck Surgery; Rigshospitalet; Copenhagen Denmark
- Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
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Skin pH Is the Master Switch of Kallikrein 5-Mediated Skin Barrier Destruction in a Murine Atopic Dermatitis Model. J Invest Dermatol 2016; 136:127-35. [PMID: 26763432 DOI: 10.1038/jid.2015.363] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 08/05/2015] [Accepted: 08/18/2015] [Indexed: 11/09/2022]
Abstract
Elevated skin surface pH has been reported in patients with atopic dermatitis. In this study, we explored the role of skin pH in the pathogenesis of atopic dermatitis using the NC/Tnd murine atopic dermatitis model. Alkalinization of the skin of asymptomatic NC/Tnd mice housed in specific pathogen-free conditions induced kallikrein 5 and activated protease-activated receptor 2, resulting in thymic stromal lymphopoietin secretion and a cutaneous T-helper 2 allergic response. This was associated with increased transepidermal water loss and development of eczematous lesions in these specific pathogen-free NC/Tnd mice, which normally do not suffer from atopic dermatitis. Injection of recombinant thymic stromal lymphopoietin also induced scratching behavior in the specific pathogen-free NC/Tnd mice. Thymic stromal lymphopoietin production and dermatitis induced by alkalinization of the skin could be blocked by the protease-activated receptor 2 antagonist ENMD-1068. In contrast, weak acidification of eczematous skin in conventionally housed NC/Tnd mice reduced kallikrein 5 activity and ameliorated the dermatitis. Onset of the dermatitis was associated with increased epidermal filaggrin expression and impaired activity of the sodium/hydrogen exchanger 1, a known regulator of skin pH. We conclude that alterations in skin pH directly modulate kallikrein 5 activity leading to skin barrier dysfunction, itch, and dermatitis via the protease-activated receptor 2-thymic stromal lymphopoietin pathway.
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Wang P, Li L, Zhang Z, Kan Q, Gao F, Chen S. Time-dependent activity of Na+/H+ exchanger isoform 1 and homeostasis of intracellular pH in astrocytes exposed to CoCl2 treatment. Mol Med Rep 2016; 13:4443-50. [PMID: 27035646 DOI: 10.3892/mmr.2016.5067] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 02/11/2016] [Indexed: 11/06/2022] Open
Abstract
Hypoxia causes injury to the central nervous system during stroke and has significant effects on pH homeostasis. Na+/H+ exchanger isoform 1 (NHE1) is important in the mechanisms of hypoxia and intracellular pH (pHi) homeostasis. As a well-established hypoxia-mimetic agent, CoCl2 stabilizes and increases the expression of hypoxia inducible factor‑1α (HIF-1α), which regulates several genes involved in pH balance, including NHE1. However, it is not fully understood whether NHE1 is activated in astrocytes under CoCl2 treatment. In the current study, pHi and NHE activity were analyzed using the pHi‑sensitive dye BCECF‑AM. Using cariporide (an NHE1‑specific inhibitor) and EIPA (an NHE nonspecific inhibitor), the current study demonstrated that it was NHE1, not the other NHE isoforms, that was important in regulating pHi homeostasis in astrocytes during CoCl2 treatment. Additionally, the present study observed that, during the early period of CoCl2 treatment (the first 2 h), NHE1 activity and pHi dropped immediately, and NHE1 mRNA expression was reduced compared with control levels, whereas expression levels of the NHE1 protein had not yet changed. In the later period of CoCl2 treatment, NHE1 activity and pHi significantly increased compared with the control levels, as did the mRNA and protein expression levels of NHE1. Furthermore, the cell viability and injury of astrocytes was not changed during the initial 8 h of CoCl2 treatment; their deterioration was associated with the higher levels of pHi and NHE1 activity. The current study concluded that NHE1 activity and pHi homeostasis are regulated by CoCl2 treatment in a time-dependent manner in astrocytes, and may be responsible for the changes in cell viability and injury observed under hypoxia-mimetic conditions induced by CoCl2 treatment.
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Affiliation(s)
- Peng Wang
- Department of Basic Medicine, Nursing College, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Ling Li
- Department of Palliative and Hospice Care, The Ninth People's Hospital of Zhengzhou, Zhengzhou, Henan 450053, P.R. China
| | - Zhenxiang Zhang
- Department of Basic Medicine, Nursing College, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Quancheng Kan
- Clinical Pharmacology Base, Department of Infectious Disease, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Feng Gao
- Department of Neuroimmunology, Henan Academy of Medical and Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Suyan Chen
- Department of Basic Medicine, Nursing College, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
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Guissart C, Li X, Leheup B, Drouot N, Montaut-Verient B, Raffo E, Jonveaux P, Roux AF, Claustres M, Fliegel L, Koenig M. Mutation of SLC9A1, encoding the major Na+/H+ exchanger, causes ataxia-deafness Lichtenstein-Knorr syndrome. Hum Mol Genet 2014; 24:463-70. [DOI: 10.1093/hmg/ddu461] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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Abstract
HYPOTHESIS Pendrin acts as a Cl-/HCO3- exchanger and is responsible for endolymphatic fluid volume and pH homeostasis in human endolymphatic sac epithelial cells. BACKGROUND The endolymphatic sac (ES) is part of the membranous labyrinth in the inner ear that plays an important role in maintaining homeostasis of the endolymphatic fluid system. However, the exact mechanism of fluid volume and pH regulation is not fully understood yet. We aimed to demonstrate the expression of various anion exchangers (AEs), including pendrin, in cultured human endolymphatic sac epithelial (HESE) cells. METHODS Endolymphatic sac specimens were harvested during acoustic neuroma surgery (n = 24) using the translabyrinthine approach and then subcultured with high epidermal growth factor (EGF) (25 ng/ml) media and differentiated using low-EGF (0.5 ng/ml) media. The cultured cells were classified according to the morphology on TEM. The Cl-/HCO3- exchanger activity was assessed by pHi measurement using pH sensitive dye 2', 7'-bis (2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF/AM). We performed reverse transcriptase-polymerase chain reaction and immunohistochemical staining for AEs. RESULTS We determined that 7.3 ± 6.7% of cells differentiated into mitochodria-rich cells and 50.2 ± 15.1 of cells differentiated into ribosome-rich cells. bAE3, AE4, SLC26A4, SLC26A6, and SLC26A11 were also expressed in cultured HESE cells. The cultured cells had Cl-/HCO3- and Cl-/formate exchange activity on the luminal membrane, which is sensitive to anion channel inhibitors (DIDS 500 μM). Furthermore, we showed that pendrin (SLC26A4) was expressed in cultured HESE cell membranes. CONCLUSION Our results suggest that AEs, including pendrin, are expressed in epithelia of ES and may have role in maintaining ionic homeostasis, and the HESE culture system are useful for uncovering the functional role of ES epithelial cells.
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Møller MN, Caye-Thomasen P, Qvortrup K. Oxygenated fixation demonstrates novel and improved ultrastructural features of the human endolymphatic sac. Laryngoscope 2013; 123:1967-75. [PMID: 23404212 DOI: 10.1002/lary.23929] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 09/26/2012] [Accepted: 11/12/2012] [Indexed: 11/12/2022]
Abstract
OBJECTIVES/HYPOTHESIS The purpose of the present study is to describe in detail the ultrastructure of the human endolymphatic sac using a new and improved method of fixation as well as a refined surgical approach in obtaining specimens. STUDY DESIGN Transmission electron microscopy of the human endolymphatic sac, employing an oxygenated fixative. METHODS Eighteen tissue samples of the human endolymphatic sac were obtained during surgery for vestibular schwannoma using the translabyrinthine approach. The specimens were fixed in 2% glutaraldehyde in an oxygenated fluorocarbon blood substitute vehicle before preparation by routine methods for transmission electron microscopy. We focused on the epithelial cell layer, subepithelial tissue, intraluminal content, and vascular tissue in both the intra- and extraosseous part of the endolymphatic sac. RESULTS We observed well-defined endolymphatic sac epithelial cell lining in all 18 specimens. In general, we found very well-preserved specimens with well-defined intracellular structures. In contrast to the results in former studies, a minimum of fixation artifacts was observed in the present study. Three different cell types were observed in the intraosseous part of the sac: mitochondria-rich cells, ribosome-rich cells, and nonclassifiable cells. A fourth cell type was found in the extraosseous part. Novel ultrastructural features of the epithelial lining and the subepithelial layer are described and discussed. CONCLUSIONS The results in the present study indicate an improvement in obtaining human tissue with optimal fixation for ultrastructural analysis and provide several novel morphologic observations. The potential functions of the endolymphatic sac are discussed with reference to former studies.
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Affiliation(s)
- Martin Nue Møller
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, University Hospital Rigshospitalet/Gentofte, Denmark.
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Abstract
Na(+) concentrations in endolymph must be controlled to maintain hair cell function since the transduction channels of hair cells are cation-permeable, but not K(+)-selective. Flooding or fluctuations of the hair cell cytosol with Na(+) would be expected to lead to cellular dysfunction, hearing loss and vertigo. This review briefly describes cellular mechanisms known to be responsible for Na(+) homeostasis in each compartment of the inner ear, including the cochlea, saccule, semicircular canals and endolymphatic sac. The influx of Na(+) into endolymph of each of the organs is likely via passive diffusion, but these pathways have not yet been identified or characterized. Na(+) absorption is controlled by gate-keeper channels in the apical (endolymphatic) membrane of the transporting cells. Highly Na(+)-selective epithelial sodium channels (ENaCs) control absorption by Reissner's membrane, saccular extramacular epithelium, semicircular canal duct epithelium and endolymphatic sac. ENaC activity is controlled by a number of signal pathways, but most notably by genomic regulation of channel numbers in the membrane via glucocorticoid signaling. Non-selective cation channels in the apical membrane of outer sulcus epithelial cells and vestibular transitional cells mediate Na(+) and parasensory K(+) absorption. The K(+)-mediated transduction current in hair cells is also accompanied by a Na(+) flux since the transduction channels are non-selective cation channels. Cation absorption by all of these cells is regulated by extracellular ATP via apical non-selective cation channels (P2X receptors). The heterogeneous population of epithelial cells in the endolymphatic sac is thought to have multiple absorptive pathways for Na(+) with regulatory pathways that include glucocorticoids and purinergic agonists.
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Affiliation(s)
- Sung Huhn Kim
- Department of Otorhinolayrnogology, Yonsei University College of Medicine, 250 Seongsanno, Seodaemun-gu, Seoul 120-752, Republic of Korea
| | - Daniel C. Marcus
- Department of Anatomy and Physiology, Kansas State University, 228 Coles Hall, Manhattan, KS 66506-5802, USA
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Ning ZY, An YF, Qi WB, Wang H, Pan JQ, Wu XT, Liao M. Na+/H+ exchanger 1 gene expression in tissues of yellow chicken. Biochem Genet 2011; 50:227-34. [PMID: 21952874 DOI: 10.1007/s10528-011-9464-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Accepted: 04/28/2011] [Indexed: 10/17/2022]
Abstract
The Na(+)/H(+) exchanger 1 (NHE1) transmembrane protein regulates intracellular pH, cell survival, cell growth, cell differentiation and plays a critical role in the progression of some diseases, including the pathogenesis of J avian leukosis. The chicken is an ideal model to study the function of NHE1 because it has developed highly efficient Na(+)-absorptive mechanisms in its small and large intestines. To date, there has been no detailed expression analysis to determine NHE1 expression in various tissues of the chicken. We determined the mRNA and protein expression levels of avian NHE1 by real-time quantitative PCR and immunohistochemical analysis. NHE1 mRNA was detected in all chicken tissues examined. Protein expression levels varied widely among tissues and did not always correlate with mRNA expression. Determining the mRNA and protein of NHE1 expression patterns in chicken should help to delineate the NHE1 role in different tissues and its contribution to physiological and pathological processes. These data provide the basis for examining the distinct function of chicken NHE1 compared with its mammalian counterpart.
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Affiliation(s)
- Zhang-yong Ning
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
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Kim HM, Wangemann P. Failure of fluid absorption in the endolymphatic sac initiates cochlear enlargement that leads to deafness in mice lacking pendrin expression. PLoS One 2010; 5:e14041. [PMID: 21103348 PMCID: PMC2984494 DOI: 10.1371/journal.pone.0014041] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Accepted: 10/29/2010] [Indexed: 02/08/2023] Open
Abstract
Mutations of SLC26A4 are among the most prevalent causes of hereditary deafness. Deafness in the corresponding mouse model, Slc26a4−/−, results from an abnormally enlarged cochlear lumen. The goal of this study was to determine whether the cochlear enlargement originates with defective cochlear fluid transport or with a malfunction of fluid transport in the connected compartments, which are the vestibular labyrinth and the endolymphatic sac. Embryonic inner ears from Slc26a4+/− and Slc26a4−/− mice were examined by confocal microscopy ex vivo or after 2 days of organ culture. Culture allowed observations of intact, ligated or partially resected inner ears. Cochlear lumen formation was found to begin at the base of the cochlea between embryonic day (E) 13.5 and 14.5. Enlargement was immediately evident in Slc26a4−/− compared to Slc26a4+/− mice. In Slc26a4+/− and Slc26a4−/− mice, separation of the cochlea from the vestibular labyrinth by ligation at E14.5 resulted in a reduced cochlear lumen. Resection of the endolymphatic sacs at E14.5 led to an enlarged cochlear lumen in Slc26a4+/− mice but caused no further enlargement of the already enlarged cochlear lumen in Slc26a4−/− mice. Ligation or resection performed later, at E17.5, did not alter the cochlea lumen. In conclusion, the data suggest that cochlear lumen formation is initiated by fluid secretion in the vestibular labyrinth and temporarily controlled by fluid absorption in the endolymphatic sac. Failure of fluid absorption in the endolymphatic sac due to lack of Slc26a4 expression appears to initiate cochlear enlargement in mice, and possibly humans, lacking functional Slc26a4 expression.
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Affiliation(s)
- Hyoung-Mi Kim
- Anatomy and Physiology Department, Kansas State University, Manhattan, Kansas, United States of America
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Abstract
PURPOSE OF REVIEW To describe ion and water homeostatic mechanisms in the inner ear, how they are compromised in hearing disorders, and what treatments are employed to restore auditory function. RECENT FINDINGS The ion and water transport functions in the inner ear help maintain the proper endolymph K concentration required for hair cell function. Gene defects and idiopathic alterations in these transport functions cause hearing loss, but often the underlying cause is unknown. Current therapies largely involve glucocorticoid treatment, although the mechanisms of restoration are often undeterminable. Recent studies of these ion homeostatic functions in the ear are characterizing their cellular and molecular control. It is anticipated that future management of these hearing disorders will be more targeted to the cellular processes involved and improve the likelihood of hearing recovery. SUMMARY A better understanding of the ion homeostatic processes in the ear will permit more effective management of their associated hearing disorders. Sufficient insight into many homeostatic hearing disorders has now been attained to usher in a new era of better therapies and improved clinical outcomes.
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Affiliation(s)
- Dennis R Trune
- Oregon Hearing Research Center, Department of Otolaryngology Head Neck Surgery, Oregon Health & Science University, Portland, Oregon 97239-3098, USA.
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Current Opinion in Otolaryngology & Head and Neck Surgery. Current world literature. Curr Opin Otolaryngol Head Neck Surg 2010; 18:466-74. [PMID: 20827086 DOI: 10.1097/moo.0b013e32833f3865] [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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