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Abd-Elhafiz HI, Faried MA, Khodir SA, Moaty AS, Sweed EM. Ezetimibe protects against Gentamycin-induced ototoxicity in rats by antioxidants, anti-inflammatory mechanisms, and BDNF upregulation. Immunopharmacol Immunotoxicol 2024:1-16. [PMID: 39138615 DOI: 10.1080/08923973.2024.2390463] [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: 03/25/2024] [Accepted: 08/04/2024] [Indexed: 08/15/2024]
Abstract
OBJECTIVE The threat of hearing loss has become a universal reality. Gentamycin (GM) can lead to ototoxicity and may result in permanent hearing loss. This study aimed to elucidate whether the hypolipidemic drug Ezetimibe (EZE) has a possible underlying mechanism for protecting rats from GM-induced ototoxicity. METHODS AND RESULTS 30 male Wister albino rats were separated into three groups, ten in each group: control, GM, and GM + EZE. At the end of the experiment, rats underwent hearing threshold evaluation via auditory brainstem response (ABR), carotid artery blood flow velocity (CBV), and resistance (CVR) measurement, in addition to a biochemical assessment of serum malondialdehyde (MDA), nitric oxide (NO), catalase (CAT), hemeOxygenase-1 (HO-1), and tumor necrosis factor-α (TNF-α). Also, real-time PCR was employed to quantify the levels of brain-derived neurotrophic factor (BDNF). Cochlea was also studied via histological and immunohistochemical methods. GM revealed a significant increase in CVR, MDA, NO, and TNF-α and a significant decrease in ABR, CBV, CAT, HO-1, and cochlear BDNF expression. EZE supplementation revealed a significant rise in ARB in addition to CBV and a decline in CVR and protected cochlear tissues via antioxidant, anti-inflammatory, and antiapoptotic mechanisms via downregulating Caspase-3 immunoreaction, upregulating proliferating cellular nuclear antigen (PCNA) immunoreaction, and upregulating of the cochlear BDNF expression. Correlations were significantly negative between BDNF and MDA, NO, TNF-α, COX 2, and caspase-3 immunoreaction and significantly positive with CAT, HO-1, and PCNA immunoreaction. DISCUSSION EZE can safeguard inner ear tissues from GM via antioxidant, anti-inflammatory, and antiapoptotic mechanisms, as well as upregulation of BDNF mechanisms.
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Affiliation(s)
- Huda I Abd-Elhafiz
- Clinical Pharmacology Department, Faculty of Medicine, Menoufia University, Menoufia, Egypt
| | - Manar A Faried
- Anatomy and Embryology Department, Faculty of Medicine, Menoufia University, Menoufia, Egypt
| | - Suzan A Khodir
- Medical Physiology Department, Faculty of Medicine, Menoufia University, Menoufia, Egypt
| | - Asmaa Salah Moaty
- Otolaryngology department, Faculty of Medicine, Menoufia University, Menoufia, Egypt
| | - Eman M Sweed
- Clinical Pharmacology Department, Faculty of Medicine, Menoufia University, Menoufia, Egypt
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2
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Wang L, Zhang R, Jiang L, Gao S, Wu J, Jiao Y. Biomaterials as a new option for treating sensorineural hearing loss. Biomater Sci 2024; 12:4006-4023. [PMID: 38979939 DOI: 10.1039/d4bm00518j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Sensorineural hearing loss (SNHL) usually involves damage to complex auditory pathways such as inner ear cells and auditory nerves. The highly intricate and nuanced characteristics of these cells render their repair and regeneration extremely challenging, making it difficult to restore hearing to normal levels once it has been compromised. The effectiveness of traditional drugs is so minimal that they provide little help with the treatment. Fortunately, extensive experiments have demonstrated that combining biomaterials with conventional techniques significantly enhances drug effectiveness. This article reviews the research progress of biomaterials in protecting hair cells and the auditory nerve, repairing genes related to hearing, and developing artificial cochlear materials. By organizing the knowledge presented in this article, perhaps new insights can be provided for the clinical management of SNHL.
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Affiliation(s)
- Liwen Wang
- Department of Otorhinolaryngology Head and Neck Surgery, Guangzhou Twelfth People's Hospital (The Affiliated Twelfth People's Hospital of Guangzhou Medical University), Guangzhou 510620, China
- Institute of Otorhinolaryngology, Head and Neck Surgery, Guangzhou Medical University, Guangzhou 510620, China.
| | - Ruhe Zhang
- Department of Hematology, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen 518107, China
| | - Linlan Jiang
- Department of Otorhinolaryngology Head and Neck Surgery, Guangzhou Twelfth People's Hospital (The Affiliated Twelfth People's Hospital of Guangzhou Medical University), Guangzhou 510620, China
- Institute of Otorhinolaryngology, Head and Neck Surgery, Guangzhou Medical University, Guangzhou 510620, China.
| | - Shuyi Gao
- Department of Otorhinolaryngology Head and Neck Surgery, Guangzhou Twelfth People's Hospital (The Affiliated Twelfth People's Hospital of Guangzhou Medical University), Guangzhou 510620, China
- Institute of Otorhinolaryngology, Head and Neck Surgery, Guangzhou Medical University, Guangzhou 510620, China.
| | - Jun Wu
- Institute of Otorhinolaryngology, Head and Neck Surgery, Guangzhou Medical University, Guangzhou 510620, China.
- Bioscience and Biomedical Engineering Thrust, The Hong Kong University of Science and Technology (Guangzhou), Nansha, Guangzhou 511400, China.
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Yuenong Jiao
- Department of Otorhinolaryngology Head and Neck Surgery, Guangzhou Twelfth People's Hospital (The Affiliated Twelfth People's Hospital of Guangzhou Medical University), Guangzhou 510620, China
- Institute of Otorhinolaryngology, Head and Neck Surgery, Guangzhou Medical University, Guangzhou 510620, China.
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3
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Di Stadio A, Ralli M, Kaski D, Koohi N, Gioacchini FM, Kysar JW, Lalwani AK, Warnecke A, Bernitsas E. Exploring Inner Ear and Brain Connectivity through Perilymph Sampling for Early Detection of Neurological Diseases: A Provocative Proposal. Brain Sci 2024; 14:621. [PMID: 38928621 PMCID: PMC11201480 DOI: 10.3390/brainsci14060621] [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: 06/03/2024] [Revised: 06/17/2024] [Accepted: 06/19/2024] [Indexed: 06/28/2024] Open
Abstract
Recent evidence shows that it is possible to identify the elements responsible for sensorineural hearing loss, such as pro-inflammatory cytokines and macrophages, by performing perilymph sampling. However, current studies have only focused on the diagnosis of such as otologic conditions. Hearing loss is a feature of certain neuroinflammatory disorders such as multiple sclerosis, and sensorineural hearing loss (SNHL) is widely detected in Alzheimer's disease. Although the environment of the inner ear is highly regulated, there are several communication pathways between the perilymph of the inner ear and cerebrospinal fluid (CSF). Thus, examination of the perilymph may help understand the mechanism behind the hearing loss observed in certain neuroinflammatory and neurodegenerative diseases. Herein, we review the constituents of CSF and perilymph, the anatomy of the inner ear and its connection with the brain. Then, we discuss the relevance of perilymph sampling in neurology. Currently, perilymph sampling is only performed during surgical procedures, but we hypothesize a simplified and low-invasive technique that could allow sampling in a clinical setting with the same ease as performing an intratympanic injection under direct visual check. The use of this modified technique could allow for perilymph sampling in people with hearing loss and neuroinflammatory/neurodegenerative disorders and clarify the relationship between these conditions; in fact, by measuring the concentration of neuroinflammatory and/or neurodegenerative biomarkers and those typically expressed in the inner ear in aging SNHL, it could be possible to understand if SNHL is caused by aging or neuroinflammation.
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Affiliation(s)
- Arianna Di Stadio
- Department GF Ingrassia, University of Catania, 95131 Catania, Italy
- Sense Research Unit, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK; (D.K.); (N.K.)
| | - Massimo Ralli
- Organ of Sense Department, University La Sapienza, 00185 Rome, Italy;
| | - Diego Kaski
- Sense Research Unit, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK; (D.K.); (N.K.)
| | - Nehzat Koohi
- Sense Research Unit, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK; (D.K.); (N.K.)
| | - Federico Maria Gioacchini
- Ear, Nose, and Throat Unit, Department of Clinical and Molecular Sciences, Polytechnic University of Marche, 60020 Ancona, Italy;
| | - Jeffrey W. Kysar
- Otolaryngology—Head and Neck Department, Columbia University, New York, NY 10032, USA; (J.W.K.); (A.K.L.)
| | - Anil K. Lalwani
- Otolaryngology—Head and Neck Department, Columbia University, New York, NY 10032, USA; (J.W.K.); (A.K.L.)
| | - Athanasia Warnecke
- Department of Otolaryngology—Head and Neck Surgery, Hannover Medical School, 30625 Hannover, Germany;
| | - Evanthia Bernitsas
- Multiple Sclerosis Center, Neurology Department, Wayne State University, Detroit, MI 48201, USA;
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Edvardsson Rasmussen J, Li P, Laurell G, Bergquist J, Eriksson PO. Hearing loss and its association with the proteome of perilymph, cerebrospinal fluid, and tumor tissue in patients with vestibular schwannoma. Sci Rep 2024; 14:14118. [PMID: 38898156 PMCID: PMC11187212 DOI: 10.1038/s41598-024-64352-6] [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: 04/09/2024] [Accepted: 06/07/2024] [Indexed: 06/21/2024] Open
Abstract
This study examined the association between hearing loss in sporadic vestibular schwannoma patients and the proteome of perilymph (PL), cerebrospinal fluid (CSF), and vestibular schwannoma. Intraoperative sampling of PL and of CSF, and biopsy of vestibular schwannoma tissue, was performed in 32, 32, and 20 patients with vestibular schwannoma, respectively. Perilymph and CSF in three patients with meningioma and normal hearing were also sampled. The proteomes were identified by liquid chromatography coupled to high-resolution tandem mass spectrometry. Preoperative hearing function of the patients was evaluated with pure tone audiometry, with mean values at frequencies of 500, 1000, 2000, and 4000 Hz (PTA4) in the tumor-affected ear used to delineate three hearing groups. Analysis of the PL samples revealed significant upregulation of complement factor H-related protein 2 (CFHR2) in patients with severe to profound hearing loss after false discovery rate correction. Pathway analysis of biofunctions revealed higher activation scores in the severe/profound hearing loss group of leukocyte migration, viral infection, and migration of cells in PL. Upregulation of CFHR2 and activation of these pathways indicate chronic inflammation in the cochlea of vestibular schwannoma patients with severe to profound hearing loss compared with patients with normal hearing or mild hearing loss.
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Affiliation(s)
- Jesper Edvardsson Rasmussen
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden.
| | - Peng Li
- Computational Research Centre for Complex Chronic Diseases, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Göran Laurell
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | - Jonas Bergquist
- Department of Chemistry - BMC, Analytical Chemistry and Neurochemistry, Uppsala University, Uppsala, Sweden
| | - Per Olof Eriksson
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
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Altay DU, Korkmaz H, Korkmaz M, Noyan T. Relationship Between Serum Brain-Derived Neurotrophic Factor and Neurotrophin-3 Levels and Hearing Thresholds in Patients With Age-Related Hearing Loss. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2024; 67:1976-1983. [PMID: 38687186 DOI: 10.1044/2024_jslhr-23-00440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
BACKGROUND Age-related hearing loss (ARHL) is a general term used to describe the sensorineural type of hearing loss occurring in both ears in older adults. Neurotrophins are the most promising candidates for supporting the auditory nerve by increasing neuronal survival. This study aimed to help elucidate the pathophysiology of ARHL by determining whether any relationship exists between brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) levels in serum samples from patients diagnosed with ARHL. MATERIALS AND METHOD Seventy-seven individuals, a study group of 41 patients diagnosed with ARHL, and a control group of 36 participants without hearing loss were evaluated. Serum samples were collected and used to measure serum BDNF and NT-3 levels with the new Nepenthe enzyme-linked immunosorbent assay method. RESULTS Median pure-tone average results in the 2000, 4000, and 6000 Hz ranges were 52.5 (44.3-67.3) dB HL in the ARHL group and 13.5 (11.1-17.1) dB HL in the control group. The difference was statistically significant (p = .001). Although NT-3 and BDNF levels were both lower in ARHL patients than in participants without hearing loss, only the BDNF levels were significantly (p = .002) lower. Mean left and right ear word recognition scores were also lower in ARHL patients than in control groups. The ARHL group was further divided into two subgroups based on word recognition scores to evaluate significant differences in BDNF and NT-3 levels. No statistically significant difference was observed in BDNF and NT-3 levels between these subgroups. However, there was a significant difference in word recognition scores. CONCLUSIONS Low BDNF levels in the ARHL group suggest that BDNF may play a role in the pathogenesis of ARHL. Patients with low (ARHL1) and high (ARHL2) word recognition scores were compared for the first time in the literature in terms of BDNF and NT-3 levels. However, the results were not statistically significant. This article is a preliminary study and was written to provide guidance for our next comprehensive project.
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Affiliation(s)
- Diler Us Altay
- Department of Nutrition and Dietetics, Faculty of Health Sciences, Ordu University, Turkey
| | - Hakan Korkmaz
- Department of Otorhinolaryngology, Faculty of Medicine, Ordu University, Turkey
| | - Mukadder Korkmaz
- Department of Otorhinolaryngology, Faculty of Medicine, Ordu University, Turkey
| | - Tevfik Noyan
- Department of Medical Biochemistry, Faculty of Medicine, Ordu University, Turkey
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6
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St. Peter M, Brough DE, Lawrence A, Nelson-Brantley J, Huang P, Harre J, Warnecke A, Staecker H. Improving Control of Gene Therapy-Based Neurotrophin Delivery for Inner Ear Applications. Front Bioeng Biotechnol 2022; 10:892969. [PMID: 35721868 PMCID: PMC9204055 DOI: 10.3389/fbioe.2022.892969] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 04/27/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Survival and integrity of the spiral ganglion is vital for hearing in background noise and for optimal functioning of cochlear implants. Numerous studies have demonstrated that supplementation of supraphysiologic levels of the neurotrophins BDNF and NT-3 by pumps or gene therapy strategies supports spiral ganglion survival. The endogenous physiological levels of growth factors within the inner ear, although difficult to determine, are likely extremely low within the normal inner ear. Thus, novel approaches for the long-term low-level delivery of neurotrophins may be advantageous. Objectives: This study aimed to evaluate the long-term effects of gene therapy-based low-level neurotrophin supplementation on spiral ganglion survival. Using an adenovirus serotype 28-derived adenovector delivery system, the herpes latency promoter, a weak, long expressing promoter system, has been used to deliver the BDNF or NTF3 genes to the inner ear after neomycin-induced ototoxic injury in mice. Results: Treatment of the adult mouse inner ear with neomycin resulted in acute and chronic changes in endogenous neurotrophic factor gene expression and led to a degeneration of spiral ganglion cells. Increased survival of spiral ganglion cells after adenoviral delivery of BDNF or NTF3 to the inner ear was observed. Expression of BDNF and NT-3 could be demonstrated in the damaged organ of Corti after gene delivery. Hearing loss due to overexpression of neurotrophins in the normal hearing ear was avoided when using this novel vector–promoter combination. Conclusion: Combining supporting cell-specific gene delivery via the adenovirus serotype 28 vector with a low-strength long expressing promoter potentially can provide long-term neurotrophin delivery to the damaged inner ear.
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Affiliation(s)
| | | | - Anna Lawrence
- Department of Otolaryngology, University of Kansas School of Medicine, Kansas City, KS, United States
| | | | - Peixin Huang
- Department of Otolaryngology, University of Kansas School of Medicine, Kansas City, KS, United States
| | - Jennifer Harre
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Athanasia Warnecke
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Hinrich Staecker
- Department of Otolaryngology, University of Kansas School of Medicine, Kansas City, KS, United States
- *Correspondence: Hinrich Staecker,
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7
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van Dieken A, Staecker H, Schmitt H, Harre J, Pich A, Roßberg W, Lenarz T, Durisin M, Warnecke A. Bioinformatic Analysis of the Perilymph Proteome to Generate a Human Protein Atlas. Front Cell Dev Biol 2022; 10:847157. [PMID: 35573665 PMCID: PMC9096870 DOI: 10.3389/fcell.2022.847157] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 04/04/2022] [Indexed: 11/16/2022] Open
Abstract
The high complexity of the cellular architecture of the human inner ear and the inaccessibility for tissue biopsy hampers cellular and molecular analysis of inner ear disease. Sampling and analysis of perilymph may present an opportunity for improved diagnostics and understanding of human inner ear pathology. Analysis of the perilymph proteome from patients undergoing cochlear implantation was carried out revealing a multitude of proteins and patterns of protein composition that may enable characterisation of patients into subgroups. Based on existing data and databases, single proteins that are not present in the blood circulation were related to cells within the cochlea to allow prediction of which cells contribute to the individual perilymph proteome of the patients. Based on the results, we propose a human atlas of the cochlea. Finally, druggable targets within the perilymph proteome were identified. Understanding and modulating the human perilymph proteome will enable novel avenues to improve diagnosis and treatment of inner ear diseases.
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Affiliation(s)
- Alina van Dieken
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Hinrich Staecker
- Department of Otolaryngology, Head and Neck, Surgery, University of Kansas School of Medicine, Kansas City, KS, United States
| | - Heike Schmitt
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Jennifer Harre
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Andreas Pich
- Core Facility Proteomics, Hannover Medical School, Hannover, Germany
| | - Willi Roßberg
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Thomas Lenarz
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Martin Durisin
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Athanasia Warnecke
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
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8
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Durisin M, Krüger C, Pich A, Warnecke A, Steffens M, Zeilinger C, Lenarz T, Prenzler N, Schmitt H. Proteome profile of patients with excellent and poor speech intelligibility after cochlear implantation: Can perilymph proteins predict performance? PLoS One 2022; 17:e0263765. [PMID: 35239655 PMCID: PMC8893673 DOI: 10.1371/journal.pone.0263765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 01/26/2022] [Indexed: 11/20/2022] Open
Abstract
Modern proteomic analysis and reliable surgical access to gain liquid inner ear biopsies have enabled in depth molecular characterization of the cochlea microenvironment. In order to clarify whether the protein composition of the perilymph can provide new insights into individual hearing performance after cochlear implantation (CI), computational analysis in correlation to clinical performance after CI were performed based on the proteome profile derived from perilymph samples (liquid biopsies). Perilymph samples from cochlear implant recipients have been analyzed by mass spectrometry (MS). The proteins were identified using the shot-gun proteomics method and quantified and analyzed using Max Quant, Perseus and IPA software. A total of 75 perilymph samples from 68 (adults and children) patients were included in the analysis. Speech perception data one year after implantation were available for 45 patients and these were used for subsequent analysis. According to their hearing performance, patients with excellent (n = 22) and poor (n = 14) performance one year after CI were identified and used for further analysis. The protein composition and statistically significant differences in the two groups were detected by relative quantification of the perilymph proteins. With this procedure, a selection of 287 proteins were identified in at least eight samples in both groups. In the perilymph of the patients with excellent and poor performance, five and six significantly elevated proteins were identified respectively. These proteins seem to be involved in different immunological processes in excellent and poor performer. Further analysis on the role of specific proteins as predictors for poor or excellent performance among CI recipients are mandatory. Combinatory analysis of molecular inner ear profiles and clinical performance data using bioinformatics analysis may open up new possibilities for patient stratification. The impact of such prediction algorithms on diagnosis and treatment needs to be established in further studies.
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Affiliation(s)
- Martin Durisin
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Caroline Krüger
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Andreas Pich
- Core Facility Proteomics, Hannover Medical School, Hannover, Germany
| | - Athanasia Warnecke
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
- Cluster of Excellence of the German Research Foundation (DFG; “Deutsche Forschungsgemeinschaft”) “Hearing4all”, Hannover Medical School, Hannover, Germany
| | - Melanie Steffens
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Carsten Zeilinger
- BMWZ (Zentrum für Biomolekulare Wirkstoffe), Gottfried-Wilhelm-Leibniz University, Hannover, Germany
| | - Thomas Lenarz
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
- Cluster of Excellence of the German Research Foundation (DFG; “Deutsche Forschungsgemeinschaft”) “Hearing4all”, Hannover Medical School, Hannover, Germany
| | - Nils Prenzler
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
| | - Heike Schmitt
- Department of Otolaryngology, Hannover Medical School, Hannover, Germany
- Cluster of Excellence of the German Research Foundation (DFG; “Deutsche Forschungsgemeinschaft”) “Hearing4all”, Hannover Medical School, Hannover, Germany
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9
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Peter MS, Warnecke A, Staecker H. A Window of Opportunity: Perilymph Sampling from the Round Window Membrane Can Advance Inner Ear Diagnostics and Therapeutics. J Clin Med 2022; 11:jcm11020316. [PMID: 35054010 PMCID: PMC8781055 DOI: 10.3390/jcm11020316] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 12/29/2021] [Accepted: 01/06/2022] [Indexed: 12/12/2022] Open
Abstract
In the clinical setting, the pathophysiology of sensorineural hearing loss is poorly defined and there are currently no diagnostic tests available to differentiate between subtypes. This often leaves patients with generalized treatment options such as steroids, hearing aids, or cochlear implantation. The gold standard for localizing disease is direct biopsy or imaging of the affected tissue; however, the inaccessibility and fragility of the cochlea make these techniques difficult. Thus, the establishment of an indirect biopsy, a sampling of inner fluids, is needed to advance inner ear diagnostics and allow for the development of novel therapeutics for inner ear disease. A promising source is perilymph, an inner ear liquid that bathes multiple structures critical to sound transduction. Intraoperative perilymph sampling via the round window membrane of the cochlea has been successfully used to profile the proteome, metabolome, and transcriptome of the inner ear and is a potential source of biomarker discovery. Despite its potential to provide insight into inner ear pathologies, human perilymph sampling continues to be controversial and is currently performed only in conjunction with a planned procedure where the inner ear is opened. Here, we review the safety of procedures in which the inner ear is opened, highlight studies where perilymph analysis has advanced our knowledge of inner ear diseases, and finally propose that perilymph sampling could be done as a stand-alone procedure, thereby advancing our ability to accurately classify sensorineural hearing loss.
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Affiliation(s)
- Madeleine St. Peter
- Department of Otolaryngology-Head & Neck Surgery, University of Kansas Medical Center, Kansas City, KS 66160, USA;
| | - Athanasia Warnecke
- Department of Otolaryngology Head and Neck Surgery, Hannover Medical School, D-30625 Hanover, Germany;
| | - Hinrich Staecker
- Department of Otolaryngology-Head & Neck Surgery, University of Kansas Medical Center, Kansas City, KS 66160, USA;
- Correspondence:
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10
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Zhuang P, Phung S, Warnecke A, Arambula A, St Peter M, He M, Staecker H. Isolation of sensory hair cell specific exosomes in human perilymph. Neurosci Lett 2021; 764:136282. [PMID: 34619343 PMCID: PMC9171839 DOI: 10.1016/j.neulet.2021.136282] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/20/2021] [Accepted: 08/25/2021] [Indexed: 11/24/2022]
Abstract
Evaluation of hearing loss patients using clinical audiometry has been unable to give a definitive cellular or molecular diagnosis, hampering the development of treatments of sensorineural hearing loss. However, biopsy of inner ear tissue without losing residual hearing function for pathologic diagnosis is extremely challenging. In a clinical setting, perilymph can be accessed, potentially allowing the development of fluid based diagnostic tests. Recent approaches to improving inner ear diagnostics have been focusing on the evaluation of the proteomic or miRNA profiles of perilymph. Inspired by recent characterization and classification of many neurodegenerative diseases using exosomes which not only are produced in locally in diseased tissue but are transported beyond the blood brain barrier, we demonstrate the isolation of human inner ear specific exosomes using a novel ultrasensitive immunomagnetic nano pom-poms capture-release approach. Using perilymph samples harvested from surgical procedures, we were able to isolate exosomes from sensorineural hearing loss patients in only 2-5 μL of perilymph. By isolating sensory hair cell derived exosomes through their expression level of myosin VIIa, we for the first-time sample material from hair cells in the living human inner ear. This work sets up the first demonstration of immunomagnetic capture-release nano pom-pom isolated exosomes for liquid biopsy diagnosis of sensorineural hearing loss. With the ability to isolate exosomes derived from different cell types for molecular characterization, this method also can be developed for analyzing exosomal biomarkers from more accessible patient tissue fluids such as plasma.
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Affiliation(s)
- Pei Zhuang
- Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, FL 32608, USA
| | - Suiching Phung
- Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, FL 32608, USA
| | - Athanasia Warnecke
- Department of Otolaryngology Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Alexandra Arambula
- Department of Otolaryngology Head and Neck Surgery, University of Kansas School of Medicine, Kansas City, KS 66160, USA
| | - Madeleine St Peter
- Department of Otolaryngology Head and Neck Surgery, University of Kansas School of Medicine, Kansas City, KS 66160, USA
| | - Mei He
- Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, FL 32608, USA
| | - Hinrich Staecker
- Department of Otolaryngology Head and Neck Surgery, University of Kansas School of Medicine, Kansas City, KS 66160, USA.
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11
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Zhang Y, Long J, Ren J, Huang X, Zhong P, Wang B. Potential Molecular Biomarkers of Vestibular Schwannoma Growth: Progress and Prospects. Front Oncol 2021; 11:731441. [PMID: 34646772 PMCID: PMC8503266 DOI: 10.3389/fonc.2021.731441] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 09/06/2021] [Indexed: 12/25/2022] Open
Abstract
Vestibular schwannomas (VSs, also known as acoustic neuromas) are relatively rare benign brain tumors stem from the Schwann cells of the eighth cranial nerve. Tumor growth is the paramount factor for neurosurgeons to decide whether to choose aggressive treatment approach or careful follow-up with regular magnetic resonance imaging (MRI), as surgery and radiation can introduce significant trauma and affect neurological function, while tumor enlargement during long-term follow-up will compress the adjacent nerves and tissues, causing progressive hearing loss, tinnitus and vertigo. Recently, with the deepening research of VS biology, some proteins that regulate merlin conformation changes, inflammatory cytokines, miRNAs, tissue proteins and cerebrospinal fluid (CSF) components have been proposed to be closely related to tumor volume increase. In this review, we discuss advances in the study of biomarkers that associated with VS growth, providing a reference for exploring the growth course of VS and determining the optimal treatment strategy for each patient.
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Affiliation(s)
- Yu Zhang
- Department of Pharmacy, Huashan Hospital, Fudan University, Shanghai, China
| | - Jianfei Long
- Department of Pharmacy, Huashan Hospital, Fudan University, Shanghai, China
| | - Junwei Ren
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Xiang Huang
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Ping Zhong
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Bin Wang
- Department of Pharmacy, Huashan Hospital, Fudan University, Shanghai, China
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12
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Shew M, Wichova H, Warnecke A, Lenarz T, Staecker H. Evaluating Neurotrophin Signaling Using MicroRNA Perilymph Profiling in Cochlear Implant Patients With and Without Residual Hearing. Otol Neurotol 2021; 42:e1125-e1133. [PMID: 33973949 DOI: 10.1097/mao.0000000000003182] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
HYPOTHESIS MicroRNAs predicted to regulate neurotrophin signaling can be found in human perilymph. BACKGROUND Animal and human temporal bone studies suggest that spiral ganglion health can affect cochlear implant (CI) outcomes. Neurotrophins have been identified as a key factor in the maintenance of spiral ganglion health. Changes in miRNAs may regulate neurotrophin signaling and may reflect neurotrophin expression levels. METHODS Perilymph sampling was carried out in 18 patients undergoing cochlear implantation or stapedotomy. Expression of miRNAs in perilymph was evaluated using an Agilent miRNA gene chip. Using ingenuity pathway analysis (IPA) software, miRNAs targeting neurotrophin signaling pathway genes present in a cochlear cDNA library were annotated. Expression levels of miRNAs in perilymph were correlated to the patients' preoperative pure-tone average. RESULTS Expression of mRNAs coding for neurotrophins and their receptors were identified in tissue obtained from normal human cochlea during skull base surgery. We identified miRNAs predicted to regulate these signaling cascades, including miR-1207-5p, miR-4651, miR-103-3p, miR-100-5p, miR-221-3p, miR-200-3p. There was a correlation between poor preoperative hearing and lower expression of miR-1207 (predicted to regulate NTR3) and miR-4651 (predicted to regulate NTR2). Additionally, miR-3960, miR-4481, and miR-675 showed significant differences in expression level when comparing mild and profound hearing loss patients. CONCLUSIONS Expression of some miRNAs that are predicted to regulate neurotrophin signaling in the perilymph of cochlear implant patients vary with the patient's level of residual hearing. These miRNAs may serve as biomarkers for changes in neurotrophin signaling.
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Affiliation(s)
- Matthew Shew
- Department of Otolaryngology Head and Neck Surgery, Washington University School of Medicine in St. Louis, St. Louis, Missouri
| | - Helena Wichova
- Department of Otolaryngology Head and Neck Surgery, University of Kansas School of Medicine, Kansas City, Kansas
| | - Athanasia Warnecke
- Department of Otolaryngology, Medizinische Hochschule Hannover, Hannover
- Cluster of Excellence "Hearing4all" of the German Research Foundation (EXC 1077), Germany
| | - Thomas Lenarz
- Department of Otolaryngology, Medizinische Hochschule Hannover, Hannover
- Cluster of Excellence "Hearing4all" of the German Research Foundation (EXC 1077), Germany
| | - Hinrich Staecker
- Department of Otolaryngology Head and Neck Surgery, University of Kansas School of Medicine, Kansas City, Kansas
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13
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Schmitt HA, Pich A, Prenzler NK, Lenarz T, Harre J, Staecker H, Durisin M, Warnecke A. Personalized Proteomics for Precision Diagnostics in Hearing Loss: Disease-Specific Analysis of Human Perilymph by Mass Spectrometry. ACS OMEGA 2021; 6:21241-21254. [PMID: 34471729 PMCID: PMC8387986 DOI: 10.1021/acsomega.1c01136] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 07/09/2021] [Indexed: 05/11/2023]
Abstract
Despite a vast amount of data generated by proteomic analysis on cochlear fluid, novel clinically applicable biomarkers of inner ear diseases have not been identified hitherto. The aim of the present study was to analyze the proteome of human perilymph from cochlear implant patients, thereby identifying putative changes of the composition of the cochlear fluid perilymph due to specific diseases. Sampling of human perilymph was performed during cochlear implantation from patients with clinically or radiologically defined inner ear diseases like enlarged vestibular aqueduct (EVA; n = 14), otosclerosis (n = 10), and Ménière's disease (n = 12). Individual proteins were identified by a shotgun proteomics approach and data-dependent acquisition, thereby revealing 895 different proteins in all samples. Based on quantification values, a disease-specific protein distribution in the perilymph was demonstrated. The proteins short-chain dehydrogenase/reductase family 9C member 7 and esterase D were detected in nearly all samples of Ménière's disease patients, but not in samples of patients suffering from EVA and otosclerosis. The presence of both proteins in the inner ear tissue of adult mice and neonatal rats was validated by immunohistochemistry. Whether these proteins have the potential for a biomarker in the perilymph of Ménière's disease patients remains to be elucidated.
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Affiliation(s)
- Heike A. Schmitt
- Department
of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
- Cluster
of Excellence of the German Research Foundation (DFG; “Deutsche
Forschungsgemeinschaft”) “Hearing4all”, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Andreas Pich
- Core
Facility Proteomics, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Nils K. Prenzler
- Department
of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
- Cluster
of Excellence of the German Research Foundation (DFG; “Deutsche
Forschungsgemeinschaft”) “Hearing4all”, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Thomas Lenarz
- Department
of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
- Cluster
of Excellence of the German Research Foundation (DFG; “Deutsche
Forschungsgemeinschaft”) “Hearing4all”, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Jennifer Harre
- Department
of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
- Cluster
of Excellence of the German Research Foundation (DFG; “Deutsche
Forschungsgemeinschaft”) “Hearing4all”, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Hinrich Staecker
- Department
of Otolaryngology, Head and Neck Surgery, University of Kansas School of Medicine, 3901 Rainbow Boulevard, Kansas City, Kansas 66160, United States
| | - Martin Durisin
- Department
of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
- Cluster
of Excellence of the German Research Foundation (DFG; “Deutsche
Forschungsgemeinschaft”) “Hearing4all”, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Athanasia Warnecke
- Department
of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
- Cluster
of Excellence of the German Research Foundation (DFG; “Deutsche
Forschungsgemeinschaft”) “Hearing4all”, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
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14
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Wey K, Schirrmann R, Diesing D, Lang S, Brandau S, Hansen S, Epple M. Coating of cochlear implant electrodes with bioactive DNA-loaded calcium phosphate nanoparticles for the local transfection of stimulatory proteins. Biomaterials 2021; 276:121009. [PMID: 34280824 DOI: 10.1016/j.biomaterials.2021.121009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 06/23/2021] [Accepted: 07/02/2021] [Indexed: 12/12/2022]
Abstract
Calcium phosphate nanoparticles were loaded with nucleic acids to enhance the on-growth of tissue to a cochlear implant electrode. The nanoparticle deposition on a metallic electrode surface is possible by electrophoretic deposition (EPD) or layer-by-layer deposition (LbL). Impedance spectroscopy showed that the coating layer did not interrupt the electrical conductance at physiological frequencies and beyond (1-40,000 Hz). The transfection was demonstrated with the model cell lines HeLa and 3T3 as well as with primary explanted spiral ganglion neurons (rat) with the model protein enhanced green fluorescent protein (EGFP). The expression of the functional protein brain-derived neurotrophic factor (BDNF) was also shown. Thus, a coating of inner-ear cochlear implant electrodes with nanoparticles that carry nucleic acids will enhance the ongrowth of spiral ganglion cell axons for an improved transmission of electrical pulses.
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Affiliation(s)
- Karolin Wey
- Inorganic Chemistry and Centre for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Essen, Germany
| | - Ronja Schirrmann
- Department of Otorhinolaryngology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Detlef Diesing
- Physical Chemistry, University of Duisburg-Essen, Essen, Germany
| | - Stephan Lang
- Department of Otorhinolaryngology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Sven Brandau
- Department of Otorhinolaryngology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Stefan Hansen
- Department of Otorhinolaryngology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Matthias Epple
- Inorganic Chemistry and Centre for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Essen, Germany.
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15
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Shew M, Wichova H, St Peter M, Warnecke A, Staecker H. Distinct MicroRNA Profiles in the Perilymph and Serum of Patients With Menière's Disease. Front Neurol 2021; 12:646928. [PMID: 34220670 PMCID: PMC8242941 DOI: 10.3389/fneur.2021.646928] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 05/18/2021] [Indexed: 11/13/2022] Open
Abstract
Hypothesis: Menière's disease microRNA (miRNA) profiles are unique and are reflected in the perilymph and serum of patients. Background: Development of effective biomarkers for Menière's disease are needed. miRNAs are small RNA sequences that downregulate mRNA translation and play a significant role in a variety of disease states, ultimately making them a promising biomarker. miRNAs can be readily isolated from human inner ear perilymph and serum, and may exhibit disease-specific profiles. Methods: Perilymph sampling was performed in 10 patients undergoing surgery; 5 patients with Meniere's disease and 5 patients with otosclerosis serving as controls. miRNAs were isolated from the serum of 5 patients with bilateral Menière's disease and compared to 5 healthy age-matched controls. For evaluation of miRNAs an Agilent miRNA gene chip was used. Analysis of miRNA expression was carried out using Qlucore and Ingenuitey Pathway Analysis software. Promising miRNAs biomarkers were validated using qPCR. Results: In the perilymph of patients with Menière's disease, we identified 16 differentially expressed miRNAs that are predicted to regulate over 220 different cochlear genes. Six miRNAs are postulated to regulate aquaporin expression and twelve miRNAs are postulated to regulate a variety of inflammatory and autoimmune pathways. When comparing perilymph with serum samples, miRNA-1299 and−1270 were differentially expressed in both the perilymph and serum of Ménière's patients compared to controls. Further analysis using qPCR confirmed miRNA-1299 is downregulated over 3-fold in Meniere's disease serum samples compared to controls. Conclusions: Patients with Ménière's disease exhibit distinct miRNA expression profiles within both the perilymph and serum. The altered perilymph miRNAs identified can be linked to postulated Ménière's disease pathways and may serve as biomarkers. miRNA-1299 was validated to be downregulated in both the serum and perilymph of Menière's patients.
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Affiliation(s)
- Matthew Shew
- Department of Otolaryngology Head and Neck Surgery, Washington University School of Medicine in St. Louis, St. Louis, MO, United States
| | - Helena Wichova
- Department of Otolaryngology Head and Neck Surgery, University of Kansas School of Medicine, Kansas City, KS, United States
| | - Madeleine St Peter
- Department of Otolaryngology Head and Neck Surgery, University of Kansas School of Medicine, Kansas City, KS, United States
| | - Athanasia Warnecke
- Department of Otolaryngology Head and Neck Surgery, Hannover Medical School, Hanover, Germany
| | - Hinrich Staecker
- Department of Otolaryngology Head and Neck Surgery, University of Kansas School of Medicine, Kansas City, KS, United States
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16
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Lee JH, Hwang YJ, Li H, Kim H, Suh MW, Han D, Oh SH. In-depth proteome of perilymph in guinea pig model. Proteomics 2021; 21:e2000138. [PMID: 33459488 DOI: 10.1002/pmic.202000138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 11/13/2020] [Accepted: 12/07/2020] [Indexed: 01/10/2023]
Abstract
The vast majority of sensorineural hearing loss is caused by impairment of the inner ear cells. Proteomic analysis of perilymph may therefore improve our understanding of inner ear diseases and hearing loss. However, the investigation of the human perilymph proteome was limited due to technical difficulties in perilymph sampling. The guinea pig (Cavia porcellus) is frequently used as an experimental model in preclinical hearing research. In this study, we analyzed samples of perilymph collected from 12 guinea pigs to overcome limited experimental information regarding its proteome. We identified a total of 1413 proteins, establishing a greatly expanded proteome of the previously inferred guinea pig perilymph. This provides a comprehensive proteomic resource for the research community, which will facilitate future molecular-phenotypic studies using the guinea pig as an experimental model of relevance to human inner ear biology.
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Affiliation(s)
- Jung Hun Lee
- Proteomics Core Facility, Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea
| | - Yu-Jung Hwang
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul, South Korea
| | - Hui Li
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul, South Korea
| | - Hyeyoon Kim
- Proteomics Core Facility, Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea
| | - Myung-Whan Suh
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul, South Korea
| | - Dohyun Han
- Proteomics Core Facility, Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea
| | - Seung-Ha Oh
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul, South Korea
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17
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Lin CC, Huang TL. Brain-derived neurotrophic factor and mental disorders. Biomed J 2020; 43:134-142. [PMID: 32386841 PMCID: PMC7283564 DOI: 10.1016/j.bj.2020.01.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 01/21/2020] [Accepted: 01/21/2020] [Indexed: 12/26/2022] Open
Abstract
Brain-derived neurotrophic factor (BDNF) is a neurotrophin that modulates neuroplasticity in the brain, and is one of the most widely investigated molecule in psychiatric disorders. The researches of BDNF emcompassed the advance of investigative techniques of past decades. BDNF researches ranged from protein quantilization, to RNA expression measurements, to DNA sequencing, and lately but not lastly, epigenetic studies. In this review, we will briefly address findings on BDNF protein levels, mRNA expression, Val66Met polymorphism, and epigenetic modifications, in schizophrenia, major depressive disorder (MDD), and bipolar disorder.
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Affiliation(s)
- Chin-Chuen Lin
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Tiao-Lai Huang
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan; Genomic and Proteomic Core Laboratory, Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
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