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Li L, Chen D, Lin X, Luo J, Tan J, Ding D, Li P. Antioxidative Stress-Induced Destruction to Cochlear Cells Caused by Blind Antioxidant Therapy. Otolaryngol Head Neck Surg 2024; 170:1421-1429. [PMID: 38314899 DOI: 10.1002/ohn.659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 11/21/2023] [Accepted: 01/06/2024] [Indexed: 02/07/2024]
Abstract
OBJECTIVE Verification that blind and excessive use of antioxidants leads to antioxidant stress which exacerbates cochlear cell damage. STUDY DESIGN Basic research. SETTING The Third Affiliated Hospital of Sun Yat-Sen University. METHODS We compared and quantified hair cell-like house ear institute-organ of corti 1 (HEI-OC1) cell density, cell viability, and apoptosis caused by different concentrations of N-acetylcysteine (NAC) via Hoechst staining, Cell Counting Kit 8, Hoechst with propidium iodide staining, and Annexin V with propidium iodide (PI) staining. Apoptosis induced by high concentrations of M40403 and coenzyme Q10 in cochlear explants was analyzed and compared by cochlear dissection and activated caspase 3 labeling. RESULTS With the increase of NAC concentration (0-1000 μmol/L), cell density decreased consequently and reached the lowest at 1000 μmol/L (****P ≤ .0001). Cell viability is also declining (**P < .01). The number of Annexin V-fluorescein isothiocyanate-labeled cells and PI-labeled cells increased with increasing NAC concentration after treatment of HEI-OC1 cells for 48 hours. The proportion of apoptotic cells also rose (*P < .05, **P < .01). Cochlear hair cells (HCs) treated with low concentrations of M40403 and coenzyme Q10 for 48 hours showed no damage. When the concentrations of M40403 and coenzyme Q10 were increased (concentrations>30 μmol/L), HC damage began, followed by a dose-dependent increase in HC loss (*P < .001, **P < .0001). Activated caspase-3 was clearly apparent in cochlear explants treated with 50 μmol/L M40403 and coenzyme Q10 compared with cochlear explants without added M40403 and coenzyme Q10. CONCLUSION These experimental results suggest that inappropriate application of antioxidants can cause severe damage to normal cochlear HCs.
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Affiliation(s)
- Liling Li
- Department of Otolaryngology-Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guang Zhou, Guangdong, China
| | - Dan Chen
- Department of Otolaryngology-Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guang Zhou, Guangdong, China
| | - Xuexin Lin
- Department of Otolaryngology-Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guang Zhou, Guangdong, China
| | - Jia Luo
- Department of Otolaryngology-Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guang Zhou, Guangdong, China
| | - Jingqian Tan
- Department of Otolaryngology-Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guang Zhou, Guangdong, China
| | - Dalian Ding
- Center for Hearing and Deafness, Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, Amherst, New York, USA
| | - Peng Li
- Department of Otolaryngology-Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guang Zhou, Guangdong, China
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Lin X, Li L, Luo J, Chen D, Tan J, Li P. Cobalt-induced apoptosis of cochlear organotypic cultures and HEI-OC1 cells is mediated by Dicer. Neurotoxicology 2024; 100:85-99. [PMID: 38101458 DOI: 10.1016/j.neuro.2023.12.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 12/08/2023] [Accepted: 12/11/2023] [Indexed: 12/17/2023]
Abstract
Cobalt is widely used in the medical industry, mainly including cobalt alloy joint implants and cobalt-chromium porcelain crowns. However, unexplained ototoxicity and neurotoxicity often occur in the clinical use of cobalt agents at present, which limits the development of the cobalt industry. In this study, based on the clinical problem of cobalt ototoxicity, we first conducted an extensive search and collation of related theories, and on this basis, prepared an HEI-OC1 cell model and basilar membrane organotypic cultures after cobalt treatment. We used immunofluorescence staining, western blot, CCK8, and si-RNA to investigate the mechanism of cobalt ototoxicity, to discover its potential therapeutic targets. After comparing the reactive oxygen species, mitochondrial transmembrane potential, apoptosis-related protein expression, and cell viability of different treatment groups, the following conclusions were drawn: cobalt causes oxidative stress in the inner ear, which leads to apoptosis of inner ear cells; inhibition of oxidative stress and apoptosis can alleviate the damage of cobalt on inner ear cells; and the Dicer protein plays a role in the mechanism of inner ear damage and is a potential target for the treatment of cobalt-induced inner ear damage. Taken together, these results suggest that cobalt-induced ototoxicity triggered by oxidative stress activates a cascade of apoptotic events where cCaspase-3 decreases Dicer levels and amplifies this apoptotic pathway. It may be possible to prevent and treat cobalt ototoxicity by targeting this mechanism.
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Affiliation(s)
- Xuexin Lin
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Liling Li
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Jia Luo
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Dan Chen
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Jingqian Tan
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Peng Li
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.
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3
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Tomova Z, Vlahova A, Zlatev S, Stoeva I, Tomov D, Davcheva D, Hadzhigaev V. Clinical Evaluation of Corrosion Resistance, Ion Release, and Biocompatibility of CoCr Alloy for Metal-Ceramic Restorations Produced by CAD/CAM Technologies. Dent J (Basel) 2023; 11:166. [PMID: 37504232 PMCID: PMC10378696 DOI: 10.3390/dj11070166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/30/2023] [Accepted: 07/04/2023] [Indexed: 07/29/2023] Open
Abstract
BACKGROUND CAD/CAM technologies facilitate using powder CoCr alloys to produce metal-ceramic dental restorations. However, base alloys may induce oxidative stress in the oral cavity due to corrosion and ion release. This study evaluated resistance to corrosion and release of metal ions from 3D printed CoCr dental alloy and their effect on oral oxidative stress. METHODS Metal-ceramic crowns with 3D printed copings from CoCr alloy EOS CobaltChrome SP2 (EOS, Germany) were fabricated for 35 patients. Inductively coupled plasma mass spectrometry (ICP-MS) was used for measuring the concentration of Co and Cr ions in non-stimulated saliva before prosthetic treatment (BPT), at 2 h and 7 days after the dental treatment (APT2, APT7, respectively). Open circuit potentials (Eocp) were evaluated at APT2 and APT7. Estimating oral oxidative stress, measurements of 8-isoprostaglandin F2-alpha were conducted using liquid chromatography-tandem mass spectrometry (LC-MS/MS) at stages BPT, APT2, and APT7. RESULTS Salivary Co level increased at APT2 and decreased to the initial levels at APT7. No statistical difference was found between the levels of 8-isoPGF2-alpha measured, and between the Eocp measurements at APT2 and APT7. CONCLUSIONS The studied alloy showed stable corrosion resistance and the metal ion release did not induce oral oxidative stress.
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Affiliation(s)
- Zlatina Tomova
- Department of Prosthetic Dental Medicine, Faculty of Dental Medicine, Medical University of Plovdiv, 3, Hristo Botev blvd, 4002 Plovdiv, Bulgaria
| | - Angelina Vlahova
- Department of Prosthetic Dental Medicine, Faculty of Dental Medicine, Medical University of Plovdiv, 3, Hristo Botev blvd, 4002 Plovdiv, Bulgaria
| | - Stefan Zlatev
- Department of Prosthetic Dental Medicine, Faculty of Dental Medicine, Medical University of Plovdiv, 3, Hristo Botev blvd, 4002 Plovdiv, Bulgaria
| | - Ilyana Stoeva
- Department of Diagnostic Imaging, Dental Allergology and Physiotherapy, Faculty of Dental Medicine, Medical University of Plovdiv, 3, Hristo Botev blvd, 4002 Plovdiv, Bulgaria
| | - Desislav Tomov
- Department of Bioorganic Chemistry, Faculty of Pharmacy, Medical University of Plovdiv, 15-A "Vasil Aprilov" blvd, 4002 Plovdiv, Bulgaria
| | - Delyana Davcheva
- Department of Clinical Laboratory, Faculty of Pharmacy, University Multi-Profile Hospital for Active Treatment St. George Plovdiv, Research Institute at Medical University of Plovdiv, Medical University of Plovdiv, 15-A "Vasil Aprilov" blvd, 4002 Plovdiv, Bulgaria
| | - Viktor Hadzhigaev
- Department of Prosthetic Dental Medicine, Faculty of Dental Medicine, Medical University of Plovdiv, 3, Hristo Botev blvd, 4002 Plovdiv, Bulgaria
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Hirani RAK, Wu H, Asif AH, Rafique N, Shi L, Zhang S, Wu Z, Zhang LC, Wang S, Yin Y, Saunders M, Sun H. Cobalt oxide functionalized ceramic membrane for 4-hydroxybenzoic acid degradation via peroxymonosulfate activation. JOURNAL OF HAZARDOUS MATERIALS 2023; 448:130874. [PMID: 36716559 DOI: 10.1016/j.jhazmat.2023.130874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 12/18/2022] [Accepted: 01/24/2023] [Indexed: 06/18/2023]
Abstract
Membrane separation and sulfate radicals-based advanced oxidation processes (SR-AOPs) can be combined as an efficient technique for the elimination of organic pollutants. The immobilization of metal oxide catalysts on ceramic membranes can enrich the membrane separation technology with catalytic oxidation avoiding recovering suspended catalysts. Herein, nanostructured Co3O4 ceramic catalytic membranes with different Co loadings were fabricated via a simple ball-milling and calcination process. Uniform distribution of Co3O4 nanoparticles in the membrane provided sufficient active sites for catalytic oxidation of 4-hydroxybenzoic acid (HBA). Mechanistic studies were conducted to determine the reactive radicals and showed that both SO4•- and •OH were present in the catalytic process while SO4•- plays the dominant role. The anti-fouling performance of the composite Co@Al2O3 membranes was also evaluated, showing that a great flux recovery was achieved with the addition of PMS for the fouling caused by humic acid (HA).
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Affiliation(s)
| | - Hong Wu
- School of Science, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia
| | - Abdul Hannan Asif
- School of Science, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia
| | - Nasir Rafique
- School of Science, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia
| | - Lei Shi
- College of Materials Science and Engineering, Nanjing Forestry University, 210037 Nanjing, China
| | - Shu Zhang
- College of Materials Science and Engineering, Nanjing Forestry University, 210037 Nanjing, China
| | - Zhentao Wu
- Aston Institute of Materials Research, School of Engineering and Applied Science, Aston University, B4 7ET Birmingham, UK
| | - Lai-Chang Zhang
- School of Engineering, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia
| | - Shaobin Wang
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Yu Yin
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China
| | - Martin Saunders
- Centre for Microscopy, Characterisation and Analysis (CMCA), University of Western Australia, Perth, WA 6009, Australia
| | - Hongqi Sun
- School of Science, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia.
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Assessing the Clinical Value of Objective and Patient-Reported Audiovestibular Outcome Measures in the Risk Estimation of Systemic Cobalt Toxicity for Patients With a Metal-on-Metal Hip Implant. Ear Hear 2022; 43:1502-1514. [DOI: 10.1097/aud.0000000000001200] [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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Gómez-Arnaiz S, Tate RJ, Grant MH. Cobalt Neurotoxicity: Transcriptional Effect of Elevated Cobalt Blood Levels in the Rodent Brain. TOXICS 2022; 10:toxics10020059. [PMID: 35202246 PMCID: PMC8878729 DOI: 10.3390/toxics10020059] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/12/2022] [Accepted: 01/13/2022] [Indexed: 12/11/2022]
Abstract
Metal-on-metal (MoM) hip implants made of cobalt chromium (CoCr) alloy have shown early failure compared with other bearing materials. A consequence of the abnormal wear produced by these prostheses is elevated levels of cobalt in the blood of patients, which can lead to systemic conditions involving cardiac and neurological symptoms. In order to better understand the implications for patients with these implants, we carried out metal content and RNA-Seq analysis of excised tissue from rats treated intraperitonially for 28 days with low concentrations of cobalt. Cobalt blood levels in dosed rats were found to be similar to those seen in some patients with MoM implants (range: 4–38 μg/L Co in blood). Significant accumulation of cobalt was measured in a range of tissues including kidney, liver, and heart, but also in brain tissue. RNA-Seq analysis of neural tissue revealed that exposure to cobalt induces a transcriptional response in the prefrontal cortex (pref. cortex), cerebellum, and hippocampus. Many of the most up- and downregulated genes appear to correspond to choroid plexus transcripts. These results indicate that the choroid plexus could be the brain tissue most affected by cobalt. More specifically, the differentially expressed genes show a disruption of steroidogenesis and lipid metabolism. Several other transcripts also demonstrate that cobalt induces an immune response. In summary, cobalt exposure induces alterations in the brain transcriptome, more specifically, the choroid plexus, which is in direct contact with neurotoxicants at the blood–cerebrospinal fluid barrier.
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Affiliation(s)
- Sara Gómez-Arnaiz
- Wolfson Centre, Biomedical Engineering Department, University of Strathclyde, Glasgow G4 0NW, UK;
| | - Rothwelle J. Tate
- Strathclyde Institute for Pharmacy & Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, UK;
| | - Mary Helen Grant
- Wolfson Centre, Biomedical Engineering Department, University of Strathclyde, Glasgow G4 0NW, UK;
- Correspondence:
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Lin X, Luo J, Tan J, Yang L, Wang M, Li P. Experimental animal models of drug-induced sensorineural hearing loss: a narrative review. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:1393. [PMID: 34733945 PMCID: PMC8506545 DOI: 10.21037/atm-21-2508] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 08/16/2021] [Indexed: 01/19/2023]
Abstract
Objective This narrative review describes experimental animal models of sensorineural hearing loss (SNHL) caused by ototoxic agents. Background SNHL primarily results from damage to the sensory organ within the inner ear or the vestibulocochlear nerve (cranial nerve VIII). The main etiology of SNHL includes genetic diseases, presbycusis, ototoxic agents, infection, and noise exposure. Animal models with functional and anatomic damage to the sensory organ within the inner ear or the vestibulocochlear nerve mimicking the damage seen in humans are employed to explore the mechanism and potential treatment of SNHL. These animal models of SNHL are commonly established using ototoxic agents. Methods A literature search of PubMed, Embase, and Web of Science was performed for research articles on hearing loss and ototoxic agents in animal models of hearing loss. Conclusions Common ototoxic medications such as aminoglycoside antibiotics (AABs) and platinum antitumor drugs are extensively used to induce SNHL in experimental animals. The effect of ototoxic agents in vivo is influenced by the chemical mechanisms of the ototoxic agents, the species of animal, routes of administration of the ototoxic agents, and the dosage of ototoxic agents. Animal models of drug-induced SNHL contribute to understanding the hearing mechanism and reveal the function of different parts of the auditory system in humans.
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Affiliation(s)
- Xuexin Lin
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Jia Luo
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Jingqian Tan
- Department of Otolaryngology Head and Neck Surgery, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, China
| | - Luoying Yang
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Mitian Wang
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University Yuedong Hospital, Meizhou, China
| | - Peng Li
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
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8
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Ding D, Prolla T, Someya S, Manohar S, Salvi R. Roles of Bak and Sirt3 in Paraquat-Induced Cochlear Hair Cell Damage. Neurotox Res 2021; 39:1227-1237. [PMID: 33900547 DOI: 10.1007/s12640-021-00366-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 04/16/2021] [Accepted: 04/19/2021] [Indexed: 12/22/2022]
Abstract
Paraquat, a superoxide generator, can damage the cochlea causing an ototoxic hearing loss. The purpose of the study was to determine if deletion of Bak, a pro-apoptotic gene, would reduce paraquat ototoxicity or if deletion of Sirt3, which delays age-related hearing loss under caloric restriction, would increase paraquat ototoxicity. We tested these two hypotheses by treating postnatal day 3 cochlear cultures from Bak±, Bak-/-, Sirt3±, Sirt3-/-, and WT mice with paraquat and compared the results to a standard rat model of paraquat ototoxicity. Paraquat damaged nerve fibers and dose-dependently destroyed rat outer hair cells (OHCs) and inner hair cells (IHCs). Rat hair cell loss began in the base of the cochlea with a 10 μM dose and as the dose increased from 50 to 500 μM, the hair cell loss increased near the base of the cochlea and spread toward the apex of the cochlea. Rat OHC losses were consistently greater than IHC losses. Unexpectedly, in all mouse genotypes, paraquat-induced hair cell lesions were maximal near the apex of the cochlea and minimal near the base. This unusual damage gradient is opposite to that seen in paraquat-treated rats and in mice and rats treated with other ototoxic drugs. However, paraquat always induced greater OHC loss than IHC loss in all mouse strains. Contrary to our hypothesis, Bak deficient mice were more vulnerable to paraquat ototoxicity than WT mice (Bak-/- > Bak± > WT), suggesting that Bak plays a protective role against hair cell stress. Also, contrary to expectation, Sirt3-deficient mice did not differ significantly from WT mice, possibly due to the fact that Sirt3 was not experimentally upregulated in Sirt3-expressing mice prior to paraquat treatment. Our results show for the first time a gradient of ototoxic damage in mice that is greater in the apex than the base of the cochlea.
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MESH Headings
- Animals
- Animals, Newborn
- Cells, Cultured
- Cochlea/drug effects
- Cochlea/metabolism
- Cochlea/pathology
- Dose-Response Relationship, Drug
- Female
- Hair Cells, Auditory, Inner/drug effects
- Hair Cells, Auditory, Inner/metabolism
- Hair Cells, Auditory, Inner/pathology
- Hair Cells, Auditory, Outer/drug effects
- Hair Cells, Auditory, Outer/metabolism
- Hair Cells, Auditory, Outer/pathology
- Herbicides/toxicity
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Organ Culture Techniques
- Paraquat/toxicity
- Rats
- Rats, Sprague-Dawley
- Sirtuin 3/deficiency
- Sirtuin 3/genetics
- bcl-2 Homologous Antagonist-Killer Protein/deficiency
- bcl-2 Homologous Antagonist-Killer Protein/genetics
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Affiliation(s)
- Dalian Ding
- Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, Buffalo, NY, 14214, USA
| | - Tomas Prolla
- Department of Genetics and Medical Genetics, University of Wisconsin, 702 W Johnson St 1101, Madison, WI, 53715, USA
| | - Shinichi Someya
- Department of Aging and Geriatrics, University of Florida, Gainsville, FL, 32611, USA
| | - Senthilvelan Manohar
- Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, Buffalo, NY, 14214, USA
| | - Richard Salvi
- Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, Buffalo, NY, 14214, USA.
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Salcan I, Dilber M, Bayram R, Suleyman E, Erhan E, Karahan Yi S, Naz Yazici G, Coban A, Suleyman H. Effect of Taxifolin on Cobalt-induced Ototoxicity in Rats: A Biochemical and Histopathological Study. INT J PHARMACOL 2020. [DOI: 10.3923/ijp.2020.522.528] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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10
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Gómez-Arnaiz S, Tate R, Grant M. Cytotoxicity of cobalt chloride in brain cell lines - a comparison between astrocytoma and neuroblastoma cells. Toxicol In Vitro 2020; 68:104958. [DOI: 10.1016/j.tiv.2020.104958] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 07/15/2020] [Accepted: 07/27/2020] [Indexed: 12/17/2022]
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11
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Ding D, Manohar S, Jiang H, Salvi R. Hydroxypropyl-β-cyclodextrin causes massive damage to the developing auditory and vestibular system. Hear Res 2020; 396:108073. [PMID: 32956992 DOI: 10.1016/j.heares.2020.108073] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 07/03/2020] [Accepted: 08/25/2020] [Indexed: 12/14/2022]
Abstract
2-hydroxypropyl-β-cyclodextrin (HPβCD), a cholesterol chelator used to treat Niemann-Pick C1 (NPC1) lysosomal storage disease, causes hearing loss in mammals by preferentially destroying outer hair cells. Because cholesterol plays an important role in early neural development, we hypothesized that HPβCD would cause more extensive damage to postnatal cochlear and vestibular structures in than adult rats. This hypothesis was tested by administering HPβCD to adult rats and postnatal day 3 (P3) cochlear and vestibular organ cultures. Adult rats treated with HPβCD developed hearing impairment and outer hair cell loss 3-day post-treatment; damage increased with dose from the high frequency base toward the low-frequency apex. The HPβCD-induced histopathologies were more severe and widespread in cochlear and vestibular cultures at P3 than in adults. HPβCD destroyed both outer and inner hair cells, auditory nerve fibers and spiral ganglion neurons as well as type I and type II vestibular hair cells and vestibular ganglion neurons. The early stage of HPβCD damage involved disruption of hair cell mechanotransduction and destruction of stereocilia. HPβCD-mediated apoptosis in P3 cultures was most-strongly initiated by activation of the extrinsic caspase-8 cell death pathway in cochlear and vestibular hair cells and neurons followed by activation of executioner caspase-3. Thus, HPβCD is toxic to all types of postnatal cochlear and vestibular hair cells and neurons in vitro whereas in vivo it only appears to destroy outer hair cells in adult cochleae. The more severe HPβCD-induced damage in postnatal cultures could be due to greater drug bioavailability in vitro and/or greater vulnerability of the developing inner ear.
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Affiliation(s)
- Dalian Ding
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, Buffalo, NY 14214, United States
| | - Senthilvelan Manohar
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, Buffalo, NY 14214, United States
| | - Haiyan Jiang
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, Buffalo, NY 14214, United States
| | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, Buffalo, NY 14214, United States.
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12
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Leyssens L, Vinck B, Van Der Straeten C, Dhooge I, Wuyts FL, Maes LK. The ototoxic potential of cobalt from metal-on-metal hip implants: a pilot study on the patient-reported auditory, vestibular, and general neurological outcome. Int J Audiol 2020; 60:44-53. [PMID: 32687006 DOI: 10.1080/14992027.2020.1789922] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE This study aimed to systematically investigate the ototoxic potential of cobalt in patients with a metal-on-metal (MoM) hip implant, using objective auditory and vestibular assessments and a questionnaire. The results of the objective evaluation were published previously, whereas the current study focused on the questionnaire outcome and its relationship to the blood cobalt level. Design and study sample: Twenty patients (33-65 years) with a primary MoM hip implant and 20 non-implanted control subjects, matched for age, gender, and noise exposure, received a questionnaire to evaluate the presence of several hearing and balance symptoms (part 1) and general neurological issues (part 2). RESULTS Concerning part 1, the proportion of auditory-related symptoms in general (p = 0.022) and tinnitus (p = 0.047) was significantly higher in the MoM patient group, whereas no group difference was found for hyperacusis, increased listening effort, and decreased speech understanding. Concerning part 2, no significant group differences were detected. Within the MoM patient group, the questionnaire outcome was not significantly different between the low-exposure and high-exposure subgroups according to the blood Co level. CONCLUSIONS In line with our previous study, these results potentially imply Co-induced impairment to the auditory system, despite the lack of a clear dose-response relationship.
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Affiliation(s)
- Laura Leyssens
- Department of Rehabilitation Sciences, Faculty of Medicine and Health Sciences, University of Ghent, Ghent, Belgium
| | - Bart Vinck
- Department of Rehabilitation Sciences, Faculty of Medicine and Health Sciences, University of Ghent, Ghent, Belgium.,Department of Speech-Language Pathology and Audiology, University of Pretoria, Pretoria, South Africa
| | | | - Ingeborg Dhooge
- Department of Ear Nose Throat, Ghent University Hospital, Ghent, Belgium
| | - Floris L Wuyts
- Lab for Equilibrium Investigations and Aerospace, University of Antwerp, Antwerp, Belgium
| | - Leen K Maes
- Department of Rehabilitation Sciences, Faculty of Medicine and Health Sciences, University of Ghent, Ghent, Belgium
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13
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The Ototoxic Potential of Cobalt From Metal-on-Metal Hip Implants: Objective Auditory and Vestibular Outcome. Ear Hear 2020; 41:217-230. [DOI: 10.1097/aud.0000000000000747] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Ye H, Xing Y, Zhang L, Zhang J, Jiang H, Ding D, Shi H, Yin S. Bilirubin-induced neurotoxic and ototoxic effects in rat cochlear and vestibular organotypic cultures. Neurotoxicology 2018; 71:75-86. [PMID: 30578813 DOI: 10.1016/j.neuro.2018.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 12/16/2018] [Accepted: 12/18/2018] [Indexed: 12/15/2022]
Abstract
Exposure to high levels of bilirubin in hyperbilirubinemia patients and animal models can result in sensorineural deafness. However, the mechanisms underlying bilirubin-induced damage to the inner ear, including the cochlear and vestibular organs, remain unknown. The present analyses of cochlear and vestibular organotypic cultures obtained from postnatal day 3 rats exposed to bilirubin at varying concentrations (0, 10, 50, 100, or 250 μM) for 24 h revealed that auditory nerve fibers (ANFs) and vestibular nerve endings were destroyed even at low doses (10 and 50 μM). Additionally, as the bilirubin dose increased, spiral ganglion neurons (SGNs) and vestibular ganglion neurons (VGNs) exhibited gradual shrinkage in conjunction with nuclei condensation or fragmentation in a dose-dependent manner. The loss of cochlear and vestibular hair cells (HCs) was only evident in explants treated with the highest concentration of bilirubin (250 μM), and bilirubin-induced major apoptosis most likely occurred via the extrinsic apoptotic pathway. Thus, the present results indicate that inner ear neurons and fibers were more sensitive to, and exhibited more severe damage following, bilirubin-induced neurotoxicity than sensory HCs, which illustrates the underlying causes of auditory neuropathy and vestibulopathy in hyperbilirubinemia patients.
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Affiliation(s)
- Haibo Ye
- Department of Otorhinolaryngology, Affiliated Sixth People's Hospital of Shanghai Jiaotong University, 600 Yishan Road, Shanghai 200233, PR China
| | - Yazhi Xing
- Department of Otorhinolaryngology, Affiliated Sixth People's Hospital of Shanghai Jiaotong University, 600 Yishan Road, Shanghai 200233, PR China
| | - Ling Zhang
- Department of Otorhinolaryngology, Affiliated Sixth People's Hospital of Shanghai Jiaotong University, 600 Yishan Road, Shanghai 200233, PR China
| | - Jianhui Zhang
- Department of Otolaryngology Head and Neck Surgery, The Third People's Hospital of Chengdu, PR China
| | - Haiyan Jiang
- Center for Hearing and Deafness, Department of Communicative Disorders and Sciences State, University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Dalian Ding
- Department of Otorhinolaryngology, Affiliated Sixth People's Hospital of Shanghai Jiaotong University, 600 Yishan Road, Shanghai 200233, PR China; Center for Hearing and Deafness, Department of Communicative Disorders and Sciences State, University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA.
| | - Haibo Shi
- Department of Otorhinolaryngology, Affiliated Sixth People's Hospital of Shanghai Jiaotong University, 600 Yishan Road, Shanghai 200233, PR China.
| | - Shankai Yin
- Department of Otorhinolaryngology, Affiliated Sixth People's Hospital of Shanghai Jiaotong University, 600 Yishan Road, Shanghai 200233, PR China
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15
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Abstract
A typical cochleogram was plotted to investigate hair cell densities as a percentage along the whole length of the basilar membrane (BM) of the rabbit, the length of the BM and the width of the organ of Corti. We generated surface preparations of cochlea from adult, healthy New Zealand White (NZW) rabbits. The numbers of inner hair cells (IHCs) and outer hair cells (OHCs) were counted from images acquired from a digital camera attached to an Olympus light microscope with a scale of 100 μm as a primary unit drawn continuously, and the numbers of IHCs and OHCs were converted to densities at 10% intervals along the length of the cochlea. Meanwhile, the length of the BM and the width of the organ of Corti were calculated. The average length of the cochlea was 14.504 ± 0.403 mm, while the total number of IHCs and the numbers of OHCs in the first, second, and third rows were 1556 ± 13, 1840 ± 47, 1842 ± 46, and 1840 ± 45, respectively, accounting for 21.98%, 26.00%, 26.02%, and 26.00% of the total number of cells, respectively. The densities of each row of OHCs reported in 10% intervals were greater than the densities of the IHCs corresponding to their anatomical locations within the cochlea. The densities of OHCs in each row were distributed uniformly along the BM, while the IHCs densities were not and showed a bimodal distribution with a maximum density at the apex and at 70–80% of the cochlear length from the apex but a lower density in the remaining cochlea. The width of the organ of Corti decreased successively from the apex to the base.
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16
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Zhang J, Sun H, Salvi R, Ding D. Paraquat initially damages cochlear support cells leading to anoikis-like hair cell death. Hear Res 2018; 364:129-141. [PMID: 29563067 PMCID: PMC5984146 DOI: 10.1016/j.heares.2018.03.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 02/20/2018] [Accepted: 03/09/2018] [Indexed: 12/11/2022]
Abstract
Paraquat (PQ), one of the most widely used herbicides, is extremely dangerous because it generates the highly toxic superoxide radical. When paraquat was applied to cochlear organotypic cultures, it not only damaged the outer hair cells (OHCs) and inner hair cells (IHCs), but also caused dislocation of the hair cell rows. We hypothesized that the dislocation arose from damage to the support cells (SCs) that anchors hair cells within the epithelium. To test this hypothesis, rat postnatal cochlear cultures were treated with PQ. Shortly after PQ treatment, the rows of OHCs separated from one another and migrated radially away from IHCs suggesting loss of cell-cell adhesion that hold the hair cells in proper alignment. Hair cells dislocation was associated with extensive loss of SCs in the organ of Corti, loss of tympanic border cells (TBCs) beneath the basilar membrane, the early appearance of superoxide staining and caspase-8 labeling in SCs below the OHCs and disintegration of E-cadherin and β-catenin in the organ of Corti. Damage to the TBCs and SCs occurred prior to loss of OHC or IHC loss suggesting a form of detachment-induced apoptosis referred to as anoikis.
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Affiliation(s)
- Jianhui Zhang
- Department of Otorhinolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, China; Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, 14214, USA
| | - Hong Sun
- Department of Otorhinolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, China; Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, 14214, USA
| | - Richard Salvi
- Department of Otorhinolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, China; Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, 14214, USA; Department of Audiology and Speech-Language Pathology, Asia University, Taichung, Taiwan, ROC
| | - Dalian Ding
- Department of Otorhinolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, China; Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, 14214, USA.
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17
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Cao Z, Yang Q, Yin H, Qi Q, Li H, Sun G, Wang H, Liu W, Li J. Peroxynitrite induces apoptosis of mouse cochlear hair cells via a Caspase-independent pathway in vitro. Apoptosis 2017; 22:1419-1430. [PMID: 28900799 DOI: 10.1007/s10495-017-1417-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Peroxynitrite (ONOO-) is a potent and versatile oxidant implicated in a number of pathophysiological processes. The present study was designed to investigate the effect of ONOO- on the cultured cochlear hair cells (HCs) of C57BL/6 mice in vitro as well as the possible mechanism underlying the action of such an oxidative stress. The in vitro primary cultured cochlear HCs were subjected to different concentrations of ONOO-, then, the cell survival and morphological changes were examined by immunofluorescence and transmission electron microscopy (TEM), the apoptosis was determined by Terminal deoxynucleotidyl transferase dUNT nick end labeling (TUNEL) assay, the mRNA expressions of Caspase-3, Caspase-8, Caspase-9, Apaf1, Bcl-2, and Bax were analyzed by RT-PCR, and the protein expressions of Caspase-3 and AIF were assessed by immunofluorescence. This work demonstrated that direct exposure of primary cultured cochlear HCs to ONOO- could result in a base-to-apex gradient injury of HCs in a concentration-dependent manner. Furthermore, ONOO- led to much more losses of outer hair cells than inner hair cells mainly through the induction of apoptosis of HCs as evidenced by TEM and TUNEL assays. The mRNA expressions of Caspase-8, Caspase-9, Apaf1, and Bax were increased and, meanwhile, the mRNA expression of Bcl-2 was decreased in response to ONOO- treatment. Of interesting, the expression of Caspase-3 had no significant change, whereas, the expression alteration of AIF was observed. These results suggested that ONOO- can effectively damage the survival of cochlear HCs via triggering the apoptotic pathway. The findings from this work suggest that ONOO--induced apoptosis is mediated, at least in part, via a Caspase-independent pathway in cochlear HCs.
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Affiliation(s)
- Zhixin Cao
- Department of Pathology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, 250021, People's Republic of China
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, 250021, People's Republic of China
| | - Qianqian Yang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, 250021, People's Republic of China
- Shandong Provincial Key Laboratory of Otology, Jinan, 250021, People's Republic of China
| | - Haiyan Yin
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, 250021, People's Republic of China
- Shandong Provincial Key Laboratory of Otology, Jinan, 250021, People's Republic of China
| | - Qi Qi
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, 250021, People's Republic of China
- Shandong Provincial Key Laboratory of Otology, Jinan, 250021, People's Republic of China
| | - Hongrui Li
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, 250021, People's Republic of China
- Shandong Provincial Key Laboratory of Otology, Jinan, 250021, People's Republic of China
| | - Gaoying Sun
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, 250021, People's Republic of China
- Shandong Provincial Key Laboratory of Otology, Jinan, 250021, People's Republic of China
| | - Hongliang Wang
- Laboratory of Physical and Chemical Analysis, Shandong Academy of Occupational Health and Occupational Medicine, Shandong Academy of Medical Sciences, Jinan, 250062, People's Republic of China
| | - Wenwen Liu
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, 250021, People's Republic of China.
- Shandong Provincial Key Laboratory of Otology, Jinan, 250021, People's Republic of China.
| | - Jianfeng Li
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, 250021, People's Republic of China.
- Shandong Provincial Key Laboratory of Otology, Jinan, 250021, People's Republic of China.
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18
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Stewart WJ, Johansen JL, Liao JC. A non-toxic dose of cobalt chloride blocks hair cells of the zebrafish lateral line. Hear Res 2017; 350:17-21. [PMID: 28412580 PMCID: PMC5495470 DOI: 10.1016/j.heares.2017.04.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 02/10/2017] [Accepted: 04/03/2017] [Indexed: 01/17/2023]
Abstract
Experiments on the flow-sensitive lateral line system of fishes have provided important insights into the function and sensory transduction of vertebrate hair cells. A common experimental approach has been to pharmacologically block lateral line hair cells and measure how behavior changes. Cobalt chloride (CoCl2) blocks the lateral line by inhibiting calcium movement through the membrane channels of hair cells, but high concentrations can be toxic, making it unclear whether changes in behavior are due to a blocked lateral line or poor health. Here, we identify a non-toxic treatment of cobalt that completely blocks lateral line hair cells. We exposed 5-day post fertilization zebrafish larvae to CoCl2 concentrations ranging from 1 to 20 mM for 15 min and measured 1) the spiking rate of the afferent neurons contacting hair cells and 2) the larvae's health and long-term survival. Our results show that a 15-min exposure to 5 mM CoCl2 abolishes both spontaneous and evoked afferent firing. This treatment does not change swimming behavior, and results in >85% survival after 5 days. Weaker treatments of CoCl2 did not eliminate afferent activity, while stronger treatments caused close to 50% mortality. Our work provides a guideline for future zebrafish investigations where physiological confirmation of a blocked lateral line system is required.
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Affiliation(s)
- William J Stewart
- Department of Biology, Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, USA
| | - Jacob L Johansen
- Department of Biology, Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, USA
| | - James C Liao
- Department of Biology, Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, USA.
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19
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Prakash Krishnan Muthaiah V, Ding D, Salvi R, Roth JA. Carbaryl-induced ototoxicity in rat postnatal cochlear organotypic cultures. ENVIRONMENTAL TOXICOLOGY 2017; 32:956-969. [PMID: 27296064 DOI: 10.1002/tox.22296] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 05/16/2016] [Accepted: 05/21/2016] [Indexed: 06/06/2023]
Abstract
Carbaryl, a widely used carbamate-based insecticide, is a potent anticholinesterase known to induce delayed neurotoxicity following chronic exposure. However, its potential toxic effects on the cochlea, the sensory organ for hearing that contains cholinergic efferent neurons and acetylcholine receptors on the hair cells (HC) and spiral ganglion neurons has heretofore not been evaluated. To assess ototoxic potential of carbaryl, cochlear organotypic cultures from postnatal day 3 rats were treated with doses of carbaryl ranging from 50 to 500 μM for 48 h up to 96 h. Carbaryl damaged both the sensory HC and spiral ganglion neurons in a dose- and duration-dependent manner. HC and neuronal damage was observed at carbaryl concentrations as low as 50 μM after 96-h treatment and 100 μM after 48-h treatment. Hair cell was greatest in the high frequency basal region of the cochlea and progressively decreased towards the apex consistent with the majority of ototoxic drugs. In contrast, damage to the spiral ganglion neurons was of similar magnitude in the basal and apical regions of the cochlea. Carbaryl damage was characterized by soma shrinkage, nuclear condensation and fragmentation, and blebbing, morphological features of programmed cell death. Carbaryl upregulated the expression of executioner caspase-3 in HC and spiral ganglion neurons indicating that cellular damage occurred primarily by caspase-mediated apoptosis. These results suggest that chronic exposure to carbaryl and other carbamate anticholinesterases may be ototoxic. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 956-969, 2017.
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Affiliation(s)
| | - Dalian Ding
- Center for Hearing and Deafness, University at Buffalo, Buffalo, New York, 14214
| | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, Buffalo, New York, 14214
| | - Jerome A Roth
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York, 14214
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20
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Yu J, Ding D, Sun H, Salvi R, Roth JA. Trimethyltin-induced cochlear degeneration in rat. J Otol 2016; 11:118-126. [PMID: 29937820 PMCID: PMC6002597 DOI: 10.1016/j.joto.2016.07.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 07/27/2016] [Accepted: 07/29/2016] [Indexed: 12/28/2022] Open
Abstract
Trimethyltin (TMT) is an occupational and environmental health hazard behaving as a potent neurotoxin known to affect the central nervous system as well as the peripheral auditory system. However, the mechanisms underlying TMT-induced ototoxicity are poorly understood. To elucidate the effects of TMT on the cochlea, a single injection of 4 or 8 mg/kg TMT was administered intraperitoneally to adult rats. The compound action potential (CAP) threshold was used to assess the functional status of the cochlea and histological techniques were used to assess the condition of the hair cells and auditory nerve fibers. TMT at 4 mg/kg produced a temporary CAP threshold elevation of 25–60 dB that recovered by 28 d post-treatment. Although there was no hair cell loss with the 4 mg/kg dose, there was a noticeable loss of auditory nerve fibers particularly beneath the inner hair cells. TMT at 8 mg/kg produced a large permanent CAP threshold shift that was greatest at the high frequencies. The CAP threshold shift was associated with the loss of outer hair cells and inner hair cells in the basal, high-frequency region of the cochlea, considerable loss of auditory nerve fibers and a significant loss of spiral ganglion neurons in the basal turn. Spiral ganglion neurons showed evidence of soma shrinkage and nuclear condensation and fragmentation, morphological features of apoptotic cell death. TMT-induced damage was greatest in the high-frequency, basal region of the cochlea and the nerve fibers beneath the inner hair cells were the most vulnerable structures.
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Affiliation(s)
- Jintao Yu
- Department of Otolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY 14214, USA
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Dalian Ding
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY 14214, USA
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
- Corresponding author. Center for Hearing and Deafness, State University at Buffalo, Buffalo, NY 14214, USA. Fax: +1 716 829 2980.
| | - Hong Sun
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY 14214, USA
| | - Jerome A. Roth
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, NY 14214, USA
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21
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Ototoxicity of Divalent Metals. Neurotox Res 2016; 30:268-82. [DOI: 10.1007/s12640-016-9627-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 04/21/2016] [Accepted: 04/22/2016] [Indexed: 12/16/2022]
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