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Yu W, Zong S, Du P, Zhou P, Li H, Wang E, Xiao H. Role of the Stria Vascularis in the Pathogenesis of Sensorineural Hearing Loss: A Narrative Review. Front Neurosci 2021; 15:774585. [PMID: 34867173 PMCID: PMC8640081 DOI: 10.3389/fnins.2021.774585] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 10/28/2021] [Indexed: 12/20/2022] Open
Abstract
Sensorineural hearing loss is a common sensory impairment in humans caused by abnormalities in the inner ear. The stria vascularis is regarded as a major cochlear structure that can independently degenerate and influence the degree of hearing loss. This review summarizes the current literature on the role of the stria vascularis in the pathogenesis of sensorineural hearing loss resulting from different etiologies, focusing on both molecular events and signaling pathways, and further attempts to explore the underlying mechanisms at the cellular and molecular biological levels. In addition, the deficiencies and limitations of this field are discussed. With the rapid progress in scientific technology, new opportunities are arising to fully understand the role of the stria vascularis in the pathogenesis of sensorineural hearing loss, which, in the future, will hopefully lead to the prevention, early diagnosis, and improved treatment of sensorineural hearing loss.
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Affiliation(s)
- Wenting Yu
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shimin Zong
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Peiyu Du
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Peng Zhou
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hejie Li
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Enhao Wang
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hongjun Xiao
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Topaloğlu Ö, Şahin B. Hearing Impairment and Audiological Alterations in Euthyroid Hashimoto's Thyroiditis. ORL J Otorhinolaryngol Relat Spec 2021; 84:238-246. [PMID: 34515191 DOI: 10.1159/000517931] [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: 04/04/2021] [Accepted: 06/13/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Hearing loss may be associated with autoimmune diseases, but it was less studied in Hashimoto's thyroiditis (HT). We aimed to evaluate hearing impairment and audiological alterations in adults with euthyroid HT. METHODS Adult patients with euthyroid HT (normal thyroid functions, positive antithyroid peroxidase (anti-TPO)/anti-thyroglobulin, and sonographic findings) were compared with controls. We excluded pregnant or older patients (>40 years), those with a history of otological/audiological disease or surgery, otitis media, acoustic trauma, chronic illnesses, use of alcohol, cigarette, medications, rheumatoid factor, antinuclear, antimitochondrial, antiparietal, antineutrophil cytoplasmic, anti-smooth muscle, or antigliadin antibodies, abnormal biochemical or otological findings. Tympanometry which indicates tympanic peak pressure (TPP, daPa), acoustic reflex testing (ART), pure-tone average (PTA), and transient evoked otoacoustic emission (TEOAE) were performed. We grouped the participants according to ART (positive/negative), TEOAE (normal/undetected), and PTA (≤20/>20 decibel). RESULTS Air conduction thresholds on the right ear at 500, 4,000, 6,000, and 8,000 Hz, PTA, and the left ear at 250, 4,000, 6,000, and 8,000 Hz were higher in euthyroid HT (n = 36) than in controls (n = 40) (p < 0.05). We found less negative TPP and a higher ratio of negative ART in euthyroid HT (p < 0.05). Euthyroid HT predicted undetected TEOAE and increased hearing threshold on the right ear at 500 and 8,000 Hz (p < 0.001). TEOAE detected audiological abnormality at a higher rate. Anti-TPO was positively correlated with TPP and air conduction thresholds, except the right ear at 8,000 Hz. DISCUSSION/CONCLUSION Hearing and audiological tests may be impaired in euthyroid HT. We recommend close monitoring of audiological functions in these patients. TE-OAE more specifically indicates audiological abnormality.
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Affiliation(s)
- Ömercan Topaloğlu
- Endocrinology Clinics, Kocaeli Derince Training and Research Hospital, Kocaeli, Turkey
| | - Bayram Şahin
- Otorhinolaryngology & Head and Neck Surgery Clinics, Kocaeli Derince Training and Research Hospital, Kocaeli, Turkey
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The Role of Autoimmunity in the Pathogenesis of Sudden Sensorineural Hearing Loss. Neural Plast 2018; 2018:7691473. [PMID: 30008743 PMCID: PMC6020465 DOI: 10.1155/2018/7691473] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 05/10/2018] [Indexed: 12/20/2022] Open
Abstract
Sudden sensorineural hearing loss (SSHL) is a clinically common acute symptom in otolaryngology. Although the incidence of SSHL has increased around the world in recent years, the etiology of the disease is still unclear. It has been reported that infections, ototoxic drugs, membrane labyrinth rupture, carcinomas, circulatory system diseases, autoimmune diseases, brain lesions, mental diseases, congenital or inherited diseases, and so on, are all risk factors for SSHL. Here, we discuss the autoimmune mechanisms behind SSHL, which might be induced by type II–IV allergic reactions. We also introduce the main immunosuppressive medications that have been used to treat SSHL, which will help us to identify potential targets for immune therapy.
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García-Berrocal JR, Ramírez-Camacho R, Trinidad A, Zurita M, de la Fuente R, Lobo D. Controversies and Criticisms on Designs for Experimental Autoimmune Labyrinthitis. Ann Otol Rhinol Laryngol 2016; 113:404-10. [PMID: 15174770 DOI: 10.1177/000348940411300512] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Although immune-mediated inner ear disease was reported around 25 years ago, numerous attempts to identify the inner ear antigens have been performed. Experimental animal models have been used to study the immune mechanisms involved in hearing loss and to develop new therapies. Because animal models of autoimmune labyrinthitis have been developed by means of different antigens, we cannot yet show a valid immunopathologic explanation. A critical analysis of the more relevant experimental models employed has been performed in order to validate the methodology. Comparison between these models and animals with spontaneous systemic autoimmune disease has raised more questions concerning the pathophysiology of autoimmune hearing loss. A new pathogenetic theory is suggested, involving the supporting cells of the organ of Corti.
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Affiliation(s)
- José Ramón García-Berrocal
- Service of Otorhinolaryngology, Hospital Universitario Puerta de Hierro, Autónoma University, Madrid, Spain
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Kil SH, Kalinec F. Expression and dexamethasone-induced nuclear translocation of glucocorticoid and mineralocorticoid receptors in guinea pig cochlear cells. Hear Res 2013; 299:63-78. [PMID: 23403298 PMCID: PMC3633732 DOI: 10.1016/j.heares.2013.01.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 01/14/2013] [Accepted: 01/27/2013] [Indexed: 12/20/2022]
Abstract
Glucocorticoids (GC) are powerful anti-inflammatory agents frequently used to protect the auditory organ against damage associated with a variety of conditions, including noise exposure and ototoxic drugs as well as bacterial and viral infections. In addition to glucocorticoid receptors (GC-R), natural and synthetic GC are known to bind mineralocorticoid receptors (MC-R) with great affinity. We used light and laser scanning confocal microscopy to investigate the expression of GC-R and MC-R in different cell populations of the guinea pig cochlea, and their translocation to different cell compartments after treatment with the synthetic GC dexamethasone. We found expression of both types of receptors in the cytoplasm and nucleus of sensory inner and outer hair cells as well as pillar, Hensen and Deiters cells in the organ of Corti, inner and outer sulcus cells, spiral ganglion neurons and several types of spiral ligament and spiral limbus cells; stria vascularis cells expressed mostly MC-R whereas fibrocytes type IV were positive for GC-R only. GC-R and MC-R were also localized at or near the plasma membrane of pillar cells and outer hair cells, whereas GC-R were found at or near the plasma membrane of Hensen cells only. We investigated the relative levels of receptor expression in the cytoplasm and the nucleus of Hensen cells treated with dexamethasone, and found they varied in a way suggestive of dose-induced translocation. These results suggest that the oto-protective effects of GC could be associated with the concerted activation of genomic and non-genomic, GC-R and MC-R mediated signaling pathways in different regions of the cochlea.
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Affiliation(s)
- Sung-Hee Kil
- Division of Cell Biology and Genetics, House Research Institute, Los Angeles, CA, 90057, USA
| | - Federico Kalinec
- Division of Cell Biology and Genetics, House Research Institute, Los Angeles, CA, 90057, USA
- Departments of Cell & Neurobiology and Otolaryngology, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90033, USA
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Buniel MC, Geelan-Hansen K, Weber PC, Tuohy VK. Immunosuppressive therapy for autoimmune inner ear disease. Immunotherapy 2011; 1:425-34. [PMID: 19885385 DOI: 10.2217/imt.09.12] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Autoimmune inner ear disease (AIED) is a rare disease that is diagnosed after clinical suspicion and response to corticosteroids. AIED manifests as progressive, bilateral, although often asynchronous, sensorineural hearing loss and can be associated with vestibular symptoms. Since its description as a defined disease entity in 1979, the initial mainstay of treatment remains high-dose corticosteroids. Several animal models have been developed to assist in determining efficacy of immunosuppression in AIED, and several clinical studies have also investigated the role of both steroid and steroid-sparing treatments. Here we discuss the basic science and clinical research surrounding the history of immunosuppressive therapy in AIED.
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Affiliation(s)
- Maria C Buniel
- Cleveland Clinic, Lerner Research Institute, Department of Immunology, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
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The role of FasL and Fas in health and disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 647:64-93. [PMID: 19760067 DOI: 10.1007/978-0-387-89520-8_5] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The FS7-associated cell surface antigen (Fas, also named CD95, APO-1 or TNFRSF6) attracted considerable interest in the field of apoptosis research since its discovery in 1989. The groups of Shin Yonehara and Peter Krammer were the first reporting extensive apoptotic cell death induction upon treating cells with Fas-specific monoclonal antibodies.1,2 Cloning of Fas3 and its ligand,4,5 FasL (also known as CD178, CD95L or TNFSF6), laid the cornerstone in establishing this receptor-ligand system as a central regulator of apoptosis in mammals. Therapeutic exploitation of FasL-Fas-mediated cytotoxicity was soon an ambitous goal and during the last decade numerous strategies have been developed for its realization. In this chapter, we will briefly introduce essential general aspects of the FasL-Fas system before reviewing its physiological and pathophysiological relevance. Finally, FasL-Fas-related therapeutic tools and concepts will be addressed.
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Abstract
PURPOSE OF REVIEW The role of the immune system in mediating inner ear pathology has received considerable attention over the past two decades. The purpose of this paper is to summarize recent basic science research into the pathogenesis of autoimmune inner ear disease (AIED), review the current diagnostic work-up for patients with suspected AIED, and delineate treatment strategies. RECENT FINDINGS Basic science and clinical studies have been performed to delineate the mechanisms by which autoimmune processes may affect the ear and to develop treatment strategies to reverse this pathology. AIED refers to a rapidly progressive (over a course of weeks to months) sensorineural hearing loss that responds to the administration of corticosteroids. In addition, systemic autoimmune diseases (eg, vasculitides, lupus, Wegener granulomatosis) can secondarily affect the inner ear. Although a number of diagnostic tests for AIED have been advocated, the diagnosis of this entity is still predicated on a positive therapeutic response to corticosteroid administration. Alternate immunosuppressive regimens, designed to be used in patients who cannot be weaned off corticosteroids or whose disease becomes refractory to treatment, have proven to be difficult to develop. Methotrexate, which initially showed promise, has recently been shown to be ineffective in preventing progression of hearing loss. Further research is required to better delineate the pathophysiologic mechanisms involved in AIED and to establish more effective and better tolerated treatment regimens. SUMMARY The original enthusiasm that was generated by the concept that immune-mediated mechanisms may mediate reversible forms of inner ear pathology has been tempered by the realities conveyed by scientific research. The pathophysiology of AIED is still not well understood. Multiple potential mechanisms have been identified that can result in immune-mediated inner ear pathology. The diagnosis of AIED is based on clinical presentation and response to the administration of corticosteroids. Diagnostic testing may support the diagnosis, and the results of a recent multicenter study should clarify the role of immunologic testing in the diagnosis of this entity. Treatment options are limited, with corticosteroids being the only validated treatment option, and methotrexate offering no significant benefit to patients. The role of cyclophosphamide is restricted to patients willing to endure the attendant risks. With the advent of cochlear implants, the administration of toxic medications to preserve hearing at all costs is a less desirable option.
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Affiliation(s)
- Michael J Ruckenstein
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Pennsylvania, 3400 Spruce Street, 5 Ravdin, Philadelphia, PA 19104, USA.
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Abstract
Autoimmune sensorineural hearing loss has been increasingly recognized as a clinical entity since its description by McCabe in 1979. Recognition and proper management of this condition is important, as it is one of the very few forms of sensorineural hearing loss that can be successfully treated by medical therapy. Recent studies have provided experimental evidence to suggest that immune processes can cause sensorineural hearing loss in animals and humans. However, antigenic targets within the inner ear are diverse and as a result conclusive evidence for specific autoimmune damage to the inner ear has been elusive. This review focuses on the recent progress in understanding of the aetio-pathogenesis of autoimmune hearing loss along with a description of the various clinical conditions in which they occur. Recent advances in the laboratory diagnosis and management of this interesting condition are also described.
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Affiliation(s)
- J Mathews
- Department of Otolaryngology, Royal Liverpool University Hospital, Wigan, UK.
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Abstract
Since the report of Duke in which an allergic etiology was considered to be the cause of Meniere's disease, the hypothesis that a certain type of Meniere's disease is generated through immuno-pathological mechanisms has been advocated for 70 years. During this period, another entity of immune-mediated inner ear disorders, i. e., autoimmune inner ear disease was introduced. Fundamental immunological phenomena of the inner ear have been rapidly elucidated since 1980. The endolymphatic sac is the only site which contains immuno-competent cells within the inner ear. The inner ear is capable of mounting active immune responses when appropriately stimulated and the endolymphatic sac plays an integral function for inner ear immune response. Actually, many reports have been published that link immunity and Meniere's disease with a variety of proposed immune-related etiologies from autoimmunity to non-autoimmunity. It is suggested that immune injury to the endolymphatic sac plays an important role in the pathogenesis of Meniere's disease. These functional and morphological circumstances strongly suggest that an immunological etiology of Meniere's disease is not theoretically unfounded.
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Affiliation(s)
- Shunichi Tomiyama
- Department of Otorhinolaryngology, Tama-Nagayama Hospital, Nippon Medical School, Tama-shi, Tokyo, Japan.
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Bodmer D, Brors D, Pak K, Bodmer M, Ryan AF. Gentamicin-induced hair cell death is not dependent on the apoptosis receptor Fas. Laryngoscope 2003; 113:452-5. [PMID: 12616196 DOI: 10.1097/00005537-200303000-00012] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES/HYPOTHESIS The hair cells are the most vulnerable elements in the cochlea, and damage to them is the most common cause of sensorineural hearing loss. Understanding the intracellular events that lead to the death of hair cells is a key to developing protective strategies. The Fas death receptor-mediated apoptotic pathway is well studied and plays an important role in the elimination of damaged cells in a number of different cellular systems. We have studied the role of the Fas receptor in aminoglycoside-mediated toxicity in vitro. We employed the MRL/MpJ-Fas mouse, which does not express a functional Fas receptor. STUDY DESIGN Response of Fas-deficient hair cells to gentamicin was compared with the response of normal hair cells in vitro. METHODS Basal turn organ of Corti explants from p3-5 mice were maintained in tissue culture and treated with gentamicin for 72 hours. The explants were fixed and were stained with phalloidin, and counting was performed. RESULTS There was no difference in hair cell loss between Fas mutant mice and control MRL/MpJ mice with a functional Fas receptor. CONCLUSION The gentamicin-mediated hair cell death is not dependent on a functional Fas receptor.
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Affiliation(s)
- Daniel Bodmer
- Department of Surgery, Division of Otolaryngology, University of California-San Diego School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093, USA
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Berrocal JRG, Ramírez-Camacho R. Sudden sensorineural hearing loss: supporting the immunologic theory. Ann Otol Rhinol Laryngol 2002; 111:989-97. [PMID: 12450172 DOI: 10.1177/000348940211101107] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Sudden deafness constitutes a diagnostic challenge. Classically, 2 causes, viral and vascular, are considered in the origin of idiopathic sudden hearing loss. More recently added to the list of possibilities are rupture of the membranous labyrinth and immune-mediated sensorineural hearing loss. The latter can be either primary and localized to the inner ear or, in perhaps fewer than one third of cases, secondary to generalized systemic autoimmune disease. The purpose of the present review is to define immune-mediated sudden sensorineural hearing loss as a distinctive entity, on the basis of clinical, immunologic, and pathological findings, and suggest a profile of the typical patient.
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MESH Headings
- Adrenal Cortex Hormones/therapeutic use
- Autoantibodies/analysis
- Autoimmune Diseases/complications
- Blotting, Western
- Complement Activation
- Ear, Inner/immunology
- Ear, Inner/physiopathology
- Genotype
- Hearing Loss, Sensorineural/diagnosis
- Hearing Loss, Sensorineural/drug therapy
- Hearing Loss, Sensorineural/etiology
- Hearing Loss, Sensorineural/immunology
- Hearing Loss, Sensorineural/physiopathology
- Hearing Loss, Sudden/diagnosis
- Hearing Loss, Sudden/drug therapy
- Hearing Loss, Sudden/etiology
- Hearing Loss, Sudden/immunology
- Hearing Loss, Sudden/physiopathology
- Humans
- Immunosuppressive Agents/therapeutic use
- Magnetic Resonance Imaging
- Major Histocompatibility Complex/genetics
- Major Histocompatibility Complex/immunology
- Polymerase Chain Reaction
- T-Lymphocytes/immunology
- Temporal Bone/pathology
- Virus Diseases/complications
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Abstract
Recently this laboratory showed aldosterone, a mineralocorticoid that only enhances sodium transport, was as effective as the glucocorticoid prednisolone in restoring cochlear function in autoimmune mice. To further test this relationship between sodium transport and autoimmune hearing loss, dosage comparisons were made of prednisolone and aldosterone control of the auditory dysfunction in autoimmune MRL/MpJ-Fas(lpr) mice. Mice were tested at 2 months of age to establish baseline auditory brainstem response (ABR) thresholds, hematocrit, serum immune complexes, and anti-nuclear antibodies. Mice were then given different doses of prednisolone or aldosterone in their drinking water for 2 months. After the treatment period, most untreated water controls showed elevation of ABR thresholds due to the ongoing autoimmune disease. However, the steroid groups had significantly more mice with improved or unchanged thresholds. Both steroids improved stria vascularis morphology, although aldosterone appeared to be more effective. The immune suppressive prednisolone caused a dose-related improvement in levels of serum immune complexes and hematocrit, hallmarks of systemic autoimmune disease. Aldosterone, which has no immune suppressive function, did not alter systemic disease. The comparable efficacy of prednisolone and aldosterone in restoring auditory function suggests steroid reversal of autoimmune hearing loss in mice is due to increasing stria vascularis sodium transport and not suppression of systemic autoimmune reactions.
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Affiliation(s)
- D R Trune
- Oregon Hearing Research Center, Mail Code NRC04, Department of Otolaryngology, Head and Neck Surgery, Oregon Health Sciences University, 3181 SW Sam Jackson Park Road, 97201-3098, Portland, OR, USA.
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Abstract
There is considerable evidence to suggest that hearing and vestibular function can be influenced by autoimmune processes. A number of systemic autoimmune disorders include hearing loss and vertigo as part of their constellation of symptoms. Although classic evidence for a specific autoimmune etiology mediated by immune response directed solely at the inner ear is elusive, it appears that autoimmune damage can also exist as an entity confined to the labyrinth. Antigenic targets of autoimmunity within the labyrinth seem to be diverse. Partly because of this, the condition is difficult to diagnose. However, autoimmune disorders of the inner ear are of special interest since they are among the few forms of hearing loss that are amenable to medical treatment. Recent progress in understanding the etiology, diagnosis and treatment of autoimmune damage to the inner ear is reviewed.
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Affiliation(s)
- A F Ryan
- Department of Surgery/Otolaryngology, University of California, San Diego and VA Medical Center, California, USA.
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Trune DR, Kempton JB, Kessi M. Aldosterone (mineralocorticoid) equivalent to prednisolone (glucocorticoid) in reversing hearing loss in MRL/MpJ-Fas1pr autoimmune mice. Laryngoscope 2000; 110:1902-6. [PMID: 11081607 DOI: 10.1097/00005537-200011000-00025] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS Although the glucocorticoid prednisone is the standard therapy for autoimmune sensorineural hearing loss, what this hormone does in the ear to restore hearing is not known. MRL/MpJ-Fas(lPr) autoimmune mice consistently have shown only stria vascularis disease, implying that abnormal ion balances in the endolymph underlie cochlear dysfunction. Previously we have shown that hearing loss in these mice is reversed with prednisolone treatment. This, coupled with the complete lack of cochlear inflammation, suggests that the restoration of hearing with prednisolone is due to its sodium transport function and not to its anti-inflammatory or immune suppression effects. Therefore the hypothesis of this study was that the mineralocorticoid aldosterone, which only increases sodium transport, would be as effective as prednisolone in reversing autoimmune hearing loss. STUDY DESIGN MRL/MpJ-Fas(lPr) autoimmune mice were treated with either prednisolone or aldosterone to compare steroid effects on auditory brainstem response (ABR) thresholds and stria morphology. METHODS After baseline ABR audiometry, autoimmune mice were given prednisolone (5 mg/kg per day), aldosterone (15 microg/kg per day), or water in their drinking bottles. After 2 months of treatment the ABR thresholds were remeasured, and ears collected for histological examination. RESULTS The untreated controls showed continued elevation of ABR thresholds and edematous stria. However, thresholds in most steroid mice were improved or unchanged and their stria morphology improved, particularly with aldosterone treatment. CONCLUSIONS Restoration of hearing with steroid treatment is due to increased sodium transport to re-establish cochlear ionic balances. Aldosterone therapy may offer advantages over prednisone for long-term management of not only autoimmune hearing loss, but also other forms of nonimmune-related deafness for which steroids are currently prescribed.
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Affiliation(s)
- D R Trune
- Oregon Hearing Research Center, Department of Otolaryngology--Head and Neck Surgery, Oregon Health Sciences University, Portland 97201-3998, USA
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16
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Abstract
The known etiologies of acquired sensorineural hearing loss include acoustic trauma, physical trauma, ototoxicity, genetic predisposition, infections, Meniere's disease, aging, and autoimmune disease. Treatments are directed at eliminating or managing the underlying disease process and aiding hearing with amplification. Rarely is it possible to improve unaided hearing after sensorineural loss except when the severe to profound level of loss is reached and cochlear implantation becomes an option. Autoimmune inner ear disease, however, is a treatable cause of sensorineural hearing loss and it is important for physicians and hearing health professionals to recognize that proper early diagnosis and management strategies may result in stabilization and possibly improvement in hearing.
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Affiliation(s)
- J T Roland
- Director Otology/Neurotology, New York University Medical Center, 530 First Avenue, Suite 3C, New York, NY 10016, USA.
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Trune DR, Wobig RJ, Kempton JB, Hefeneider SH. Steroid treatment in young MRL.MpJ-Fas(lpr) autoimmune mice prevents cochlear dysfunction. Hear Res 1999; 137:167-73. [PMID: 10545644 DOI: 10.1016/s0378-5955(99)00148-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Corticosteroid therapy reverses clinical autoimmune sensorineural hearing loss, although little is known of how steroids restore normal auditory function. If suppression of systemic autoimmune processes underlies hearing restoration, then preventing autoimmune symptoms from developing should prevent cochlear dysfunction. MRL. MpJ-Fas(lpr) autoimmune mice were used to test this potential mechanism by initiating oral prednisolone treatment at 6 weeks of age, prior to autoimmune disease and hearing loss onset. The steroid treatment group was given prednisolone in their drinking water, while untreated controls were given tap water. Treatment continued for 7 months with periodic evaluations of cochlear function with auditory brainstem response (ABR) audiometry. Autoimmune mice given the steroid lived longer and did not develop levels of serum immune complexes seen in their untreated controls. Also, their ABR thresholds remained near normal throughout the 7 months of treatment, while untreated controls showed progressive threshold elevations typical for autoimmune disease. This correlation of suppressed systemic autoimmune activity and maintenance of normal cochlear function identifies one potential mechanism for autoimmune hearing loss and hearing restoration with steroid therapy. The autoimmune mouse should serve as a valuable model for future studies of the cochlear mechanisms responsive to steroid treatment in autoimmune hearing loss.
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Affiliation(s)
- D R Trune
- Oregon Hearing Research Center, Department of Otolaryngology - Head and Neck Surgery, Oregon Health Sciences University, NRC04, 3181 SW Sam Jackson Park Road, Portland, OR 97201-3098, USA.
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Trune DR, Wobig RJ, Kempton JB, Hefeneider SH. Steroid treatment improves cochlear function in the MRL.MpJ-Fas(lpr) autoimmune mouse. Hear Res 1999; 137:160-6. [PMID: 10545643 DOI: 10.1016/s0378-5955(99)00147-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Corticosteroid therapy is used to reverse autoimmune sensorineural hearing loss, although little is known of the mechanism by which this occurs. This has been due to the lack of a suitable animal model with spontaneous hearing loss that is steroid responsive. The present study examined the effects of prednisolone treatment on auditory thresholds in the MRL.MpJ-Fas(lpr) autoimmune mouse to determine its suitability as such a model. Autoimmune mice at 3.5-4. 5 months of age were evaluated by pure-tone auditory brainstem response (ABR) to establish threshold elevations due to the disease. The steroid treatment group was then given prednisolone in their drinking water for 2.5 months, while untreated controls were given tap water. Significantly more steroid treated mice survived to the time of post-treatment ABR evaluation. Half of the steroid treated ears demonstrated either improvement or no change in cochlear function compared to only 25% in the untreated controls. Overall, cochlear thresholds in the untreated controls increased by 14.7 dB, whereas no significant threshold increase was seen in the steroid treated group (4.3 dB) over the treatment period. No qualitative anatomical differences were seen in the ears of those mice surviving to the end of the study. These findings establish the autoimmune mouse as a model for studies of steroid responsive mechanisms within the ear. This could apply to autoimmune sensorineural hearing loss, as well as any hearing disorder for which steroid therapy is recommended.
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Affiliation(s)
- D R Trune
- Oregon Hearing Research Center, Department of Otolaryngology - Head and Neck Surgery, Oregon Health Sciences University, NRC04, 3181 SW Sam Jackson Park Road, Portland, OR 97201-3098, USA.
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