1
|
Pisani A, Paciello F, Del Vecchio V, Malesci R, De Corso E, Cantone E, Fetoni AR. The Role of BDNF as a Biomarker in Cognitive and Sensory Neurodegeneration. J Pers Med 2023; 13:jpm13040652. [PMID: 37109038 PMCID: PMC10140880 DOI: 10.3390/jpm13040652] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/04/2023] [Accepted: 04/08/2023] [Indexed: 04/29/2023] Open
Abstract
Brain-derived neurotrophic factor (BDNF) has a crucial function in the central nervous system and in sensory structures including olfactory and auditory systems. Many studies have highlighted the protective effects of BDNF in the brain, showing how it can promote neuronal growth and survival and modulate synaptic plasticity. On the other hand, conflicting data about BDNF expression and functions in the cochlear and in olfactory structures have been reported. Several clinical and experimental research studies showed alterations in BDNF levels in neurodegenerative diseases affecting the central and peripheral nervous system, suggesting that BDNF can be a promising biomarker in most neurodegenerative conditions, including Alzheimer's disease, shearing loss, or olfactory impairment. Here, we summarize current research concerning BDNF functions in brain and in sensory domains (olfaction and hearing), focusing on the effects of the BDNF/TrkB signalling pathway activation in both physiological and pathological conditions. Finally, we review significant studies highlighting the possibility to target BDNF as a biomarker in early diagnosis of sensory and cognitive neurodegeneration, opening new opportunities to develop effective therapeutic strategies aimed to counteract neurodegeneration.
Collapse
Affiliation(s)
- Anna Pisani
- Department of Otolaryngology Head and Neck Surgery, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
| | - Fabiola Paciello
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Valeria Del Vecchio
- Department of Neuroscience, Reproductive Sciences and Dentistry-Audiology Section, University of Naples Federico II, 80131 Naples, Italy
| | - Rita Malesci
- Department of Neuroscience, Reproductive Sciences and Dentistry-Audiology Section, University of Naples Federico II, 80131 Naples, Italy
| | - Eugenio De Corso
- Department of Otolaryngology Head and Neck Surgery, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Elena Cantone
- Department of Neuroscience, Reproductive Sciences and Dentistry-ENT Section, University of Naples Federico II, 80131 Naples, Italy
| | - Anna Rita Fetoni
- Department of Neuroscience, Reproductive Sciences and Dentistry-Audiology Section, University of Naples Federico II, 80131 Naples, Italy
| |
Collapse
|
2
|
Febles NK, Bauer MA, Ding B, Zhu X, Gallant ND, Frisina RD. A combinatorial approach to protect sensory tissue against cisplatin-induced ototoxicity. Hear Res 2022; 415:108430. [PMID: 35051751 PMCID: PMC8810742 DOI: 10.1016/j.heares.2022.108430] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 12/22/2021] [Accepted: 01/03/2022] [Indexed: 12/23/2022]
Abstract
Sensorineural Hearing Loss (SNHL) is a highly prevalent disorder involving permanent damage or loss to the inner ear's mechano-sensory hair cells and nerve fibers. Major contributing causes are ototoxic drugs, loud noises, and aging. Drug-induced hearing loss (DIHL), affects over 25% of patients treated with common therapeutics such as aminoglycoside antibiotics, loop diuretics or chemotherapeutics. A commonly used chemotherapeutic agent, cisplatin, is very effective for treating malignant tumors, but results in a majority of patients experiencing irreversible hearing loss and/or tinnitus. Additionally, since there is currently no FDA-approved treatments for SNHL, attenuation of ototoxicity is a major area of investigation in oncology, otolaryngology and hearing research. Several potential otoprotective agents have been investigated at the clinical trial stage, but none have progressed to a full FDA-approval. In this study, we investigated a combinatorial approach comprised of an antioxidant, a p53 inhibitor and a neurotrophin, as a multifactorial otoprotective treatment for cisplatin exposure. In vitro, HEI-OC1 cells, an immortalized organ of Corti epithelial cell line, pre-treated with this biotherapeutic cocktail had significantly reduced cisplatin-induced cell death, DNA fragmentation, and apoptotic activation. In an ex vivo study, rat pup D2-D3 organ of Corti explants, significant protection against cisplatin-based hair cell and neuronal loss was achieved by delivery of the same combinatorial pretreatment. Interestingly, the hair cell protection was localized to the basal and middle regions of the organ of Corti. Together, these findings highlight a novel approach to attenuate cisplatin ototoxicity and potentially prevent DIHL by addressing biological mechanisms of cisplatin ototoxicity.
Collapse
Affiliation(s)
- Nicole K. Febles
- Department of Medical Engineering, University of South Florida, Tampa, FL 33620,Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33602
| | - Mark A. Bauer
- Department of Medical Engineering, University of South Florida, Tampa, FL 33620,Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33602
| | - Bo Ding
- Department of Communicative Sciences and Disorders, University of South Florida, Tampa, FL 33602,Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33602
| | - Xiaoxia Zhu
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33602
| | - Nathan D. Gallant
- Department of Mechanical Engineering, University of South Florida, Tampa, FL 33602,Address for all correspondence: Robert Frisina, Ph.D., Department of Medical Engineering, University of South Florida, 4202 E Fowler Avenue, ENG 030, Tampa, FL 33620, Tel: 813-974-4013, , Nathan D. Gallant, Ph.D., Department of Mechanical Engineering, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620, Tel: 813-974-5840,
| | - Robert D. Frisina
- Department of Medical Engineering, University of South Florida, Tampa, FL 33620,Department of Communicative Sciences and Disorders, University of South Florida, Tampa, FL 33602,Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33602,Address for all correspondence: Robert Frisina, Ph.D., Department of Medical Engineering, University of South Florida, 4202 E Fowler Avenue, ENG 030, Tampa, FL 33620, Tel: 813-974-4013, , Nathan D. Gallant, Ph.D., Department of Mechanical Engineering, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620, Tel: 813-974-5840,
| |
Collapse
|
3
|
Jeong M, Bojkovic K, Sagi V, Stankovic KM. Molecular and Clinical Significance of Fibroblast Growth Factor 2 in Development and Regeneration of the Auditory System. Front Mol Neurosci 2022; 14:757441. [PMID: 35002617 PMCID: PMC8733209 DOI: 10.3389/fnmol.2021.757441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 11/18/2021] [Indexed: 01/25/2023] Open
Abstract
The fibroblast growth factor 2 (FGF2) is a member of the FGF family which is involved in key biological processes including development, cellular proliferation, wound healing, and angiogenesis. Although the utility of the FGF family as therapeutic agents has attracted attention, and FGF2 has been studied in several clinical contexts, there remains an incomplete understanding of the molecular and clinical function of FGF2 in the auditory system. In this review, we highlight the role of FGF2 in inner ear development and hearing protection and present relevant clinical studies for tympanic membrane (TM) repair. We conclude by discussing the future implications of FGF2 as a potential therapeutic agent.
Collapse
Affiliation(s)
- Minjin Jeong
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, United States.,Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA, United States
| | - Katarina Bojkovic
- Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA, United States
| | - Varun Sagi
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, United States.,University of Minnesota Medical School, Minneapolis, MN, United States
| | - Konstantina M Stankovic
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, United States.,Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA, United States
| |
Collapse
|
4
|
Manohar S, Ding D, Jiang H, Li L, Chen GD, Kador P, Salvi R. Combined antioxidants and anti-inflammatory therapies fail to attenuate the early and late phases of cyclodextrin-induced cochlear damage and hearing loss. Hear Res 2021; 414:108409. [PMID: 34953289 DOI: 10.1016/j.heares.2021.108409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 09/08/2021] [Accepted: 12/06/2021] [Indexed: 11/04/2022]
Abstract
Niemann-Pick C1 (NPC1) is a fatal neurodegenerative disease caused by aberrant cholesterol metabolism. The progression of the disease can be slowed by removing excess cholesterol with high-doses of 2-hyroxypropyl-beta-cyclodextrin (HPβCD). Unfortunately, HPβCD causes hearing loss; the initial first phase involves a rapid destruction of outer hair cells (OHCs) while the second phase, occurring 4-6 weeks later, involves the destruction of inner hair cells (IHCs), pillar cells, collapse of the organ of Corti and spiral ganglion neuron degeneration. To determine whether the first and/or second phase of HPβCD-induced cochlear damage is linked, in part, to excess oxidative stress or neuroinflammation, rats were treated with a single-dose of 3000 mg/kg HPβCD alone or together with one of two combination therapies. Each combination therapy was administered from 2-days before to 6-weeks after the HPβCD treatment. Combination 1 consisted of minocycline, an antibiotic that suppresses neuroinflammation, and HK-2, a multifunctional redox modulator that suppresses oxidative stress. Combination 2 was comprised of minocycline plus N-acetyl cysteine (NAC), which upregulates glutathione, a potent antioxidant. To determine if either combination therapy could prevent HPβCD-induced hearing impairment and cochlear damage, distortion product otoacoustic emissions (DPOAE) were measured to assess OHC function and the cochlear compound action potential (CAP) was measured to assess the function of IHCs and auditory nerve fibers. Cochleograms were prepared to quantify the amount of OHC, IHC and pillar cell (PC) loss. HPβCD significantly reduced DPOAE and CAP amplitudes and caused significant OHC, IHC and OPC losses with losses greater in the high-frequency base of the cochlea than the apex. Neither minocycline + HK-2 (MIN+ HK-2) nor minocycline + NAC (MIN+NAC) prevented the loss of DPOAEs, CAPs, OHCs, IHCs or IPCs caused by HPβCD. These results suggest that oxidative stress and neuroinflammation are unlikely to play major roles in mediating the first or second phase of HPβCD-induced cochlear damage. Thus, HPβCD-induced ototoxicity must be mediated by some other unknown cell-death pathway possibly involving loss of trophic support from damaged support cells or disrupted cholesterol metabolism.
Collapse
Affiliation(s)
- Senthilvelan Manohar
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, 14214, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, 68198, USA; Therapeutic Vision, Inc., Elkhorn, NE, 68022, USA
| | - Dalian Ding
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, 14214, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, 68198, USA; Therapeutic Vision, Inc., Elkhorn, NE, 68022, USA
| | - Haiyan Jiang
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, 14214, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, 68198, USA; Therapeutic Vision, Inc., Elkhorn, NE, 68022, USA
| | - Li Li
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, 14214, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, 68198, USA; Therapeutic Vision, Inc., Elkhorn, NE, 68022, USA
| | - Guang-Di Chen
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, 14214, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, 68198, USA; Therapeutic Vision, Inc., Elkhorn, NE, 68022, USA
| | - Peter Kador
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, 68198, USA; Therapeutic Vision, Inc., Elkhorn, NE, 68022, USA
| | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, 14214, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, 68198, USA; Therapeutic Vision, Inc., Elkhorn, NE, 68022, USA.
| |
Collapse
|
5
|
Fan T, Xiang MY, Zhou RQ, Li W, Wang LQ, Guan PF, Li GL, Wang YF, Li J. Effect of Sodium Salicylate on Calcium Currents and Exocytosis in Cochlear Inner Hair Cells: Implications for Tinnitus Generation. Neurosci Bull 2021; 38:69-80. [PMID: 34235622 PMCID: PMC8782992 DOI: 10.1007/s12264-021-00747-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 04/29/2021] [Indexed: 01/03/2023] Open
Abstract
Sodium salicylate is an anti-inflammatory medication with a side-effect of tinnitus. Here, we used mouse cochlear cultures to explore the effects of salicylate treatment on cochlear inner hair cells (IHCs). We found that IHCs showed significant damage after exposure to a high concentration of salicylate. Whole-cell patch clamp recordings showed that 1-5 mmol/L salicylate did not affect the exocytosis of IHCs, indicating that IHCs are not involved in tinnitus generation by enhancing their neuronal input. Instead, salicylate induced a larger peak amplitude, a more negative half-activation voltage, and a steeper slope factor of Ca2+ current. Using noise analysis of Ca2+ tail currents and qRT-PCR, we further found that salicylate increased the number of Ca2+ channels along with CaV1.3 expression. All these changes could act synergistically to enhance the Ca2+ influx into IHCs. Inhibition of intracellular Ca2+ overload significantly attenuated IHC death after 10 mmol/L salicylate treatment. These results implicate a cellular mechanism for tinnitus generation in the peripheral auditory system.
Collapse
Affiliation(s)
- Ting Fan
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai, 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Meng-Ya Xiang
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai, 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Ruo-Qiao Zhou
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai, 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Wen Li
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai, 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Li-Qin Wang
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai, 200031, China
| | - Peng-Fei Guan
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai, 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Geng-Lin Li
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai, 200031, China.
| | - Yun-Feng Wang
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai, 200031, China.
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China.
| | - Jian Li
- Clinical Laboratory Center, Children's Hospital of Fudan University, Shanghai, 201102, China.
| |
Collapse
|
6
|
Boroujeni NB, Ashkezari MD, Seifati SM. The rs6265 polymorphism might not affect the secretion of BDNF protein directedly. Meta Gene 2020. [DOI: 10.1016/j.mgene.2020.100776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
|
7
|
Zhang W, Peng Z, Yu S, Song QL, Qu TF, He L, Liu K, Gong SS. Loss of Cochlear Ribbon Synapse Is a Critical Contributor to Chronic Salicylate Sodium Treatment-Induced Tinnitus without Change Hearing Threshold. Neural Plast 2020; 2020:3949161. [PMID: 32774354 DOI: 10.1155/2020/3949161] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 05/23/2020] [Accepted: 06/12/2020] [Indexed: 12/25/2022] Open
Abstract
Tinnitus is a common auditory disease worldwide; it is estimated that more than 10% of all individuals experience this hearing disorder during their lifetime. Tinnitus is sometimes accompanied by hearing loss. However, hearing loss is not acquired in some other tinnitus generations. In this study, we injected adult rats with salicylate sodium (SS) (200 mg/kg/day for 10 days) and found no significant hearing threshold changes at 2, 4, 8, 12, 14, 16, 20, or 24 kHz (all p > 0.05). Tinnitus was confirmed in the treated rats via Behaviour Testing of Acoustic Startle Response (ASR) and Gap Prepulse Inhibition Test of Acoustic Startle Reflex (GPIAS). A immunostaining study showed that there is significant loss of anti-CtBP2 puncta (a marker of cochlear inner hair cell (HC) ribbon synapses) in treated animals in apical, middle, and basal turns (all p < 0.05). The ABR wave I amplitudes were significantly reduced at 4, 8, 12, 14, 16, and 20 kHz (all p < 0.05). No significant losses of outer HCs, inner HCs, or HC cilia were observed (all p > 0.05). Thus, our study suggests that loss of cochlear inner HC ribbon synapse after SS exposure is a contributor to the development of tinnitus without changing hearing threshold.
Collapse
|
8
|
Alemi R, Motassadi Zarandy M, Joghataei MT, Eftekharian A, Zarrindast MR, Vousooghi N. Plasticity after pediatric cochlear implantation: Implication from changes in peripheral plasma level of BDNF and auditory nerve responses. Int J Pediatr Otorhinolaryngol 2018; 105:103-110. [PMID: 29447794 DOI: 10.1016/j.ijporl.2017.12.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 12/09/2017] [Accepted: 12/12/2017] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Sensory neural hearing loss could lead to some structural and physiological changes in the auditory pathways, such as alteration in the expression of neurotrophins. These factors, especially Brain-Derived Neurotrophic Factor (BDNF), play an important role in synaptic functions and experience-related plasticity. Restoring cochlear function after hearing loss is possible through cochlear implantation (CI). Evaluation of the blood concentration changes of neurotrophins as prerequisites of plasticity could help scientists to determine the prognosis of CI as in the candidacy procedure or enhancing prosthesis function by adding the exact needed amount of BDNF to the electrode array. METHODS Here we have studied the plasma BDNF concentration before CI surgery and 6 months after using CI device in 15 pediatric CI recipients and compared this level with changes of BDNF concentration in 10 children who were using hearing aid (H.A). In addition, we searched for a possible correlation between post-surgery plasma BDNF concentration and electrical compound action potential (ECAP) and comfort-level (C-level) thresholds. RESULTS Plasma BDNF concentration in children with CI increased significantly after CI surgery, while this difference in H.A group was not significant. Analysis of repeated measures of ECAP and C-level thresholds in CI group showed that there were some kinds of steadiness during follow- up sessions for ECAP thresholds in basal and E16 of middle electrodes, whereas C-level thresholds for all selected electrodes increased significantly up to six months follow-up. Interestingly, we did not find any significant correlation between post-surgery plasma BDNF concentration and ECAP or C-level threshold changes. CONCLUSION It is concluded that changes in C-level threshold and steady state of ECAP thresholds and significant changes in BDNF concentration could be regarded as an indicator of experienced-related plasticity after CI stimulation.
Collapse
Affiliation(s)
- Razieh Alemi
- Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran; Cochlear Implant Center and Department of Otorhinolaryngology, Amir Aalam Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Masoud Motassadi Zarandy
- Cochlear Implant Center and Department of Otorhinolaryngology, Amir Aalam Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Taghi Joghataei
- Division of Neuroscience, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Neuroscience, School of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Ali Eftekharian
- Department of Otorhinolaryngology, Loghman Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Zarrindast
- Genetics Laboratory, Iranian National Center for Addiction Studies (INCAS), Tehran University of Medical Sciences, Tehran, Iran; Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Department of Cognitive Neuroscience, Institute for Cognitive Science Studies, Tehran, Iran; Genomic Center, School of Advanced Sciences, Tehran Medical Branch, Islamic Azad University, Tehran, Iran
| | - Nasim Vousooghi
- Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran; Genetics Laboratory, Iranian National Center for Addiction Studies (INCAS), Tehran University of Medical Sciences, Tehran, Iran; Research Center for Cognitive and Behavioral Sciences, Tehran University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
9
|
Jiang C, Luo B, Manohar S, Chen GD, Salvi R. Plastic changes along auditory pathway during salicylate-induced ototoxicity: Hyperactivity and CF shifts. Hear Res 2017; 347:28-40. [PMID: 27989950 PMCID: PMC5403591 DOI: 10.1016/j.heares.2016.10.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 09/30/2016] [Accepted: 10/26/2016] [Indexed: 12/27/2022]
Abstract
High dose of salicylate, the active ingredient in aspirin, has long been known to induce transient hearing loss, tinnitus and hyperacusis making it a powerful experimental tool. These salicylate-induced perceptual disturbances are associated with a massive reduction in the neural output of the cochlea. Paradoxically, the diminished neural output of the cochlea is accompanied by a dramatic increase in sound-evoked activity in the auditory cortex (AC) and several other parts of the central nervous system. Exactly where the increase in neural activity begins and builds up along the central auditory pathway are not fully understood. To address this issue, we measured sound-evoked neural activity in the cochlea, cochlear nucleus (CN), inferior colliculus (IC), and AC before and after administering a high dose of sodium salicylate (SS, 300 mg/kg). The SS-treatment abolished low-level sound-evoked responses along the auditory pathway resulting in a 20-30 dB threshold shift. While the neural output of the cochlea was substantially reduced at high intensities, the neural responses in the CN were only slightly reduced; those in the IC were nearly normal or slightly enhanced while those in the AC considerably enhanced, indicative of a progress increase in central gain. The SS-induced increase in central response in the IC and AC was frequency-dependent with the greatest increase occurring in the mid-frequency range the putative pitch of SS-induced tinnitus. This frequency-dependent hyperactivity appeared to result from shifts in the frequency receptive fields (FRF) such that the response areas of many FRF shifted/expanded toward the mid-frequencies. Our results suggest that the SS-induced threshold shift originates in the cochlea. In contrast, enhanced central gain is not localized to one region, but progressively builds up at successively higher stage of the auditory pathway either through a loss of inhibition and/or increased excitation.
Collapse
Affiliation(s)
- Chen Jiang
- Department of Neurosurgery, Anhui Provincial Hospital, 17 Lujiang Road, Hefei, Anhui 230001, China; Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Bin Luo
- Department of Neurosurgery, Anhui Provincial Hospital, 17 Lujiang Road, Hefei, Anhui 230001, China; Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Senthilvelan Manohar
- Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Guang-Di Chen
- Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA.
| | - Richard Salvi
- Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| |
Collapse
|
10
|
Lo WC, Wu CT, Lee HC, Young YH, Chang YL, Cheng PW. Evaluation of geranylgeranylacetone against cisplatin-induced ototoxicity by auditory brainstem response, heat shock proteins and oxidative levels in guinea pigs. Neurotoxicol Teratol 2017; 61:29-35. [PMID: 28344103 DOI: 10.1016/j.ntt.2017.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 02/25/2017] [Accepted: 03/21/2017] [Indexed: 11/28/2022]
Abstract
This study aims to assess whether geranylgeranylacetone (GGA) could reduce ototoxicity induced by cisplatin through upregulation of not only heat shock protein(HSP)-70, but also HSP-27 and HSP-40, and to study if GGA would reduce cisplatin-induced increase in oxidative stress. 48 guinea pigs were used in this study and treated with the following regimen: 0.5% CMC (sodium carboxymethyl cellulose) control for 7days, GGA (600mg/kg/d) for 7days, a combination of GGA (600mg/kg) for 7days and then one dose of 10mg/kg cisplatin (GGA+Cis), and a combination of CMC for 7days and then 10mg/kg cisplatin (cisplatin group). Auditory brainstem response (ABR) measurement was performed in each animal at time before treatment and 7days after the last dose. Additionally, HSPs, nitric oxide (NO), and lipid peroxidation (LPO) levels in cochlear membranous tissues were assessed. The mean ABR thresholds in the cisplatin group were significantly (p<0.05) increased when compared to the other three groups. In guinea pigs receiving both GGA and cisplatin, the mean threshold shift (TS) were smaller (p<0.05) than those of the cisplatin group, but larger (p<0.05) than those of the CMC control or GGA only group with statistical significance. Compared to the GGA only group or the group treated with GGA+Cis, the cisplatin group had the highest (p<0.05) oxidative stress (NO and LPO levels), and the lowest (p<0.05) mean HSPs expression levels. It can be concluded that GGA attenuate ototoxicity induced by cisplatin through upregulation of HSP-27, -40, and -70. Moreover, increased oxidative stress induced by cisplatin in the cochlea membranous tissue could be reduced by pre-treatment of GGA.
Collapse
Affiliation(s)
- Wu-Chia Lo
- Graduate Institute of Pathology, National Taiwan University College of Medicine, Taipei, Taiwan; Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan
| | - Chen-Tu Wu
- Graduate Institute of Pathology, National Taiwan University College of Medicine, Taipei, Taiwan; Department of Pathology, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Hillary Chiao Lee
- Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan
| | - Yi-Ho Young
- Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan
| | - Yih-Leong Chang
- Graduate Institute of Pathology, National Taiwan University College of Medicine, Taipei, Taiwan; Department of Pathology, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan.
| | - Po-Wen Cheng
- Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan.
| |
Collapse
|
11
|
|
12
|
Safety Assessment of Salicylic Acid, Butyloctyl Salicylate, Calcium Salicylate, C12–15 Alkyl Salicylate, Capryloyl Salicylic Acid, Hexyldodecyl Salicylate, Isocetyl Salicylate, Isodecyl Salicylate, Magnesium Salicylate, MEA-Salicylate, Ethylhexyl Salicylate, Potassium Salicylate, Methyl Salicylate, Myristyl Salicylate, Sodium Salicylate, TEA-Salicylate, and Tridecyl Salicylate. Int J Toxicol 2003; 22:1-108. [DOI: 10.1177/1091581803022s303] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Salicylic Acid is an aromatic acid used in cosmetic formulations as a denaturant, hair-conditioning agent, and skin-conditioning agent—miscellaneous in a wide range of cosmetic products at concentrations ranging from 0.0008% to 3%. The Calcium, Magnesium, and MEA salts are preservatives, and Potassium Salicylate is a cosmetic biocide and preservative, not currently in use. Sodium Salicylate is used as a denaturant and preservative (0.09% to 2%). The TEA salt of Salicylic Acid is used as an ultraviolet (UV) light absorber (0.0001% to 0.75%). Several Salicylic Acid esters are used as skin conditioning agents—miscellaneous (Capryloyl, 0.1% to 1%; C12–15 Alkyl, no current use; Isocetyl, 3% to 5%; Isodecyl, no current use; and Tridecyl, no current use). Butyloctyl Salicylate (0.5% to 5%) and Hexyldodecyl Salicylate (no current use) are hair-conditioning agents and skin-conditioning agents—miscellaneous. Ethylhexyl Salicylate (formerly known as Octyl Salicylate) is used as a fragrance ingredient, sunscreen agent, and UV light absorber (0.001% to 8%), and Methyl Salicylate is used as a denaturant and flavoring agent (0.0001% to 0.6%). Myristyl Salicylate has no reported function. Isodecyl Salicylate is used in three formulations, but no concentration of use information was reported. Salicylates are absorbed percutaneously. Around 10% of applied salicylates can remain in the skin. Salicylic Acid is reported to enhance percutaneous penetration of some agents (e.g., vitamin A), but not others (e.g., hydrocortisone). Little acute toxicity (LD50 in rats; >2 g/kg) via a dermal exposure route is seen for Salicylic Acid, Methyl Salicylate, Tridecyl Salicylate, and Butyloctyl Salicylate. Short-term oral, inhalation, and parenteral exposures to salicylates sufficient to produce high blood concentrations are associated primarily with liver and kidney damage. Subchronic dermal exposures to undiluted Methyl Salicylate were associated with kidney damage. Chronic oral exposure to Methyl Salicylate produced bone lesions as a function of the level of exposure in 2-year rat studies; liver damage was seen in dogs exposed to 0.15 g/kg/day in one study; kidney and liver weight increases in another study at the same exposure; but no liver or kidney abnormalities in a study at 0.167 g/kg/day. Applications of Isodecyl, Tridecyl, and Butyloctyl Salicylate were not irritating to rabbit skin, whereas undiluted Ethylhexyl Salicylate produced minimal to mild irritation. Methyl Salicylate at a 1% concentration with a 70% ethanol vehicle were irritating, whereas a 6% concentration in polyethylene glycol produced little or no irritation. Isodecyl Salicylate, Methyl Salicylate, Ethylhexyl (Octyl) Salicylate, Tridecyl Salicylate, and Butyloctyl Salicylate were not ocular irritants. Although Salicylic Acid at a concentration of 20% in acetone was positive in the local lymph node assay, a concentration of 20% in acetone/olive oil was not. Methyl Salicylate was negative at concentrations up to 25% in this assay, independent of vehicle. Maximization tests of Methyl Salicylate, Ethylhexyl Salicylate, and Butyloctyl Salicylate produced no sensitization in guinea pigs. Neither Salicylic Acid nor Tridecyl Salicylate were photosensitizers. Salicylic Acid, produced when aspirin is rapidly hydrolyzed after absorption from the gut, was reported to be the causative agent in aspirin teratogenesis in animals. Dermal exposures to Methyl Salicylate, oral exposures to Salicylic Acid, Sodium Salicylate, and Methyl Salicylate, and parenteral exposures to Salicylic Acid, Sodium Salicylate, and Methyl Salicylate are all associated with reproductive and developmental toxicity as a function of blood levels reached as a result of exposure. An exposure assessment of a representative cosmetic product used on a daily basis estimated that the exposure from the cosmetic product would be only 20% of the level seen with ingestion of a “baby” aspirin (81 mg) on a daily basis. Studies of the genotoxic potential of Salicylic Acid, Sodium Salicylate, Isodecyl Salicylate, Methyl Salicylate, Ethylhexyl (Octyl) Salicylate, Tridecyl Salicylate, and Butyloctyl Salicylate were generally negative. Methyl Salicylate, in a mouse skin-painting study, did not induce neoplasms. Likewise, Methyl Salicylate was negative in a mouse pulmonary tumor system. In clinical tests, Salicylic Acid (2%) produced minimal cumulative irritation and slight or no irritation(1.5%); TEA-Salicylate (8%) produced no irritation; Methyl Salicylate (>12%) produced pain and erythema, a 1% aerosol produced erythema, but an 8% solution was not irritating; Ethylhexyl Salicylate (4%) and undiluted Tridecyl Salicylate produced no irritation. In atopic patients, Methyl Salicylate caused irritation as a function of concentration (no irritation at concentrations of 15% or less). In normal skin, Salicylic Acid, Methyl Salicylate, and Ethylhexyl (Octyl) Salicylate are not sensitizers. Salicylic Acid is not a photosensitizer, nor is it phototoxic. Salicylic Acid and Ethylhexyl Salicylate are low-level photoprotective agents. Salicylic Acid is well-documented to have keratolytic action on normal human skin. Because of the possible use of these ingredients as exfoliating agents, a concern exists that repeated use may effectively increase exposure of the dermis and epidermis to UV radiation. It was concluded that the prudent course of action would be to advise the cosmetics industry that there is a risk of increased UV radiation damage with the use of any exfoliant, including Salicylic Acid and the listed salicylates, and that steps need to be taken to formulate cosmetic products with these ingredients as exfoliating agents so as not to increase sun sensitivity, or when increased sun sensitivity would be expected, to include directions for the daily use of sun protection. The available data were not sufficient to establish a limit on concentration of these ingredients, or to identify the minimum pH of formulations containing these ingredients, such that no skin irritation would occur, but it was recognized that it is possible to formulate cosmetic products in a way such that significant irritation would not be likely, and it was concluded that the cosmetics industry should formulate products containing these ingredients so as to be nonirritating. Although simultaneous use of several products containing Salicylic Acid could produce exposures greater than would be seen with use of baby aspirin (an exposure generally considered to not present a reproductive or developmental toxicity risk), it was not considered likely that consumers would simultaneously use multiple cosmetic products containing Salicylic Acid. Based on the available information, the Cosmetic Ingredient Review Expert Panel reached the conclusion that these ingredients are safe as used when formulated to avoid skin irritation and when formulated to avoid increasing the skin's sun sensitivity, or, when increased sun sensitivity would be expected, directions for use include the daily use of sun protection.
Collapse
|
13
|
Zeng S, Sun X, Chen Z, Yu D, Chen B, Yin S. Low, but Not High, Doses of Cisplatin Damage Cochlear Hair Cells in C57 Mouse Organotypic Cultures. ORL J Otorhinolaryngol Relat Spec 2016; 78:177-86. [PMID: 27270730 DOI: 10.1159/000446189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 04/12/2016] [Indexed: 11/19/2022]
Abstract
AIMS The purpose of this study was to investigate the characteristics of cisplatin-induced C57 mouse cochlear hair cell damage in vitro. METHODS Forty-seven cochleae harvested from 2- to 4-day-old C57 mice were used. Forty specimens were treated with different concentrations of cisplatin (10, 25, 50, 100, 400, and 1,000 μmol/l) for 48 h. The remaining seven specimens were used as a control group. RESULTS The rate of hair cell loss increased from 14.5 to 78.4% over cisplatin concentrations of 10 to 100 μmol/l, whereas hair cell loss decreased to 48.8 and 8.77% at concentrations of 400 and 1,000 μmol/l, respectively. Apoptosis was detected by DAPI staining in the areas of hair cell damage. Hair cell loss rates differed significantly among the cisplatin-treated groups. Linear regression analysis of cisplatin dose versus hair cell number showed a significant negative correlation for cisplatin doses up to 100 μmol/l and a positive correlation with further increases up to 1,000 μmol/l. CONCLUSIONS We conclude that cisplatin-induced hair cell damage was concentration dependent only up to a certain dose and that injury resistance may occur in cochlear cells treated with higher doses of cisplatin.
Collapse
Affiliation(s)
- Shan Zeng
- Department of Otorhinolaryngology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | | | | | | | | | | |
Collapse
|
14
|
Li A, He Y, Sun S, Cai C, Li H. Lysine-specific demethylase 1 inhibitors protect cochlear spiral ganglion neurons against cisplatin-induced damage. Neuroreport 2015; 26:539-47. [PMID: 26011390 DOI: 10.1097/WNR.0000000000000386] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Cisplatin is a widely used chemotherapeutic drug, but one of its side effects is ototoxicity. Epigenetic-related drugs, such as lysine-specific demethylase 1 (LSD1) inhibitors, have been reported to protect against cisplatin-induced hair cell loss by preventing demethylation of histone H3K4 (H3K4me2). However, the protective effect of LSD1 inhibitors in spiral ganglion neurons (SGNs) remains unclear. To investigate whether LSD1 inhibitors exert similar protective effects on SGNs, we treated mouse cochlear explant cultures with LSD1 inhibitors (2PCPA, S2101, or CBB1007) together with cisplatin. Low concentrations of cisplatin damaged SGNs much more than high concentrations, and blocking the demethylation of H3K4me2 with LSD1 inhibitors prevented the SGNs from injury. Reactive oxygen species are also involved in the injury process, and LSD1 inhibitors protected SGNs by increasing the expression level of the antioxidant gene Slc7a11 and decreasing the level of the pro-oxidant gene lactoperoxidase (Lpo). Our findings show that LSD1 inhibitors prevent cisplatin-induced SGN loss by regulating the demethylation of H3K4 and preventing increases of reactive oxygen species levels, which might provide a potential therapeutic strategy for cisplatin-induced hearing loss.
Collapse
|
15
|
Lo WC, Chang CM, Liao LJ, Wang CT, Young YH, Chang YL, Cheng PW. Assessment of D-methionine protecting cisplatin-induced otolith toxicity by vestibular-evoked myogenic potential tests, ATPase activities and oxidative state in guinea pigs. Neurotoxicol Teratol 2015. [PMID: 26219586 DOI: 10.1016/j.ntt.2015.07.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
To date, inadequate study has been devoted to the toxic vestibular effects caused by cisplatin. In addition, no electrophysiological examination has been conducted to assess cisplatin-induced otolith toxicity. The purposes of this study are thus two-fold: 1) to determine whether cervical vestibular-evoked myogenic potentials (VEMPs) and ocular VEMPs are practical electrophysiological methods of testing for cisplatin-induced otolith toxicity and 2) to examine if D-methionine (D-met) pre-injection would protect the otolith organs against cisplatin-induced changes in enzyme activities and/or oxidative status. Guinea pigs were intraperitoneally treated once daily with the following injections for seven consecutive days: sterile 0.9% saline control, cisplatin (5 mg/kg) only, D-met (300 mg/kg) only, or a combination of d-met (300 mg/kg) and cisplatin (5 mg/kg), respectively, with a 30 minute window in between. Each animal underwent the oVEMP and cVEMP tests before and after treatment. The changes in the biochemistry of the otolith organs, including membranous Na(+), K(+)-ATPase and Ca(2+)-ATPase, lipid peroxidation (LPO) levels and nitric oxide (NO) levels, were also evaluated. In the cisplatin-only treated guinea pigs, the mean amplitudes of the oVEMP tests were significantly (p<0.05) decreased when compared to the other three groups. In guinea pigs receiving both D-met and cisplatin, the amplitudes of their oVEMP tests were significantly larger (p<0.05) than those of the cisplatin-only group, but smaller (p<0.05) than those of the saline control or D-met-only group. However, no significant difference of the amplitudes of cVEMP tests was noted among the four groups. In comparison with the other three groups, the cisplatin-only group had the lowest (ps<0.05) mean Na(+), K(+)-ATPase and Ca(2+)-ATPase, and the highest (ps<0.05) LPO and NO levels. The oVEMP tests were feasible for the evaluation of cisplatin-related otolith dysfunction. D-Met attenuated the reduced ATPase activities and increased oxidative stress induced by cisplatin toxicity in the otolith organs.
Collapse
Affiliation(s)
- Wu-Chia Lo
- Department and Graduate Institute of Pathology, National Taiwan University College of Medicine, Taipei, Taiwan; Oriental Institute of Technology, Taipei, Taiwan
| | - Chih-Ming Chang
- Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan
| | - Li-Jen Liao
- Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan
| | - Chi-Te Wang
- Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan
| | - Yi-Ho Young
- Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan
| | - Yih-Leong Chang
- Department and Graduate Institute of Pathology, National Taiwan University College of Medicine, Taipei, Taiwan.
| | - Po-Wen Cheng
- Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan; Oriental Institute of Technology, Taipei, Taiwan.
| |
Collapse
|
16
|
Huang J, Wang P, Li M, Ge J, Chen J, Chen X. Trichostatin A reduces cisplatin-induced ototoxicity through the STAT6 signaling pathway. Int J Mol Med 2015; 36:493-500. [PMID: 26080623 DOI: 10.3892/ijmm.2015.2249] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Accepted: 06/08/2015] [Indexed: 11/05/2022] Open
Abstract
Cisplatin-induced ototoxicity limits its wide application in the treatment of cancer. A number of pro-inflammatory factors have been shown to be involved in cisplatin-induced ototoxicity. Trichostatin A (TSA) is an anti-inflammatory agent that has been shown to exert protective effects against cisplatin-induced ototoxicity. In the present study, we hypothesized that TSA may protect cochlear hair cells from cisplatin-induced damage by regulating the interleukin (IL)-4/signal transducer and activator of transcription (STAT)6 signaling pathway. Wistar rat cochlear explants were cultured in DMEM. The differentially expressed genes of the basilar membrane were identified by microarray analysis of global expression profiles. Hair cells were stained with rhodamine phalloidin and observed under a scanning electron microscope to evaluate the protective effects of TSA against cisplatin-induced cochlear hair cell damage. The levels of cytokines in the supernatant of the cultured basilar membranes was measured using ELISA. STAT6 and phosphorylated (p-)STAT6 expression was measured by western blot analysis. Morphological observation revealed that cisplatin induced the disarrangement of the cochlear hair cells, as well as the fusion and detachment of the cilia, while these aberrant alterations were inhibited by TSA, suggesting that TSA exerts a protective effect against cisplatin-induced damage to hair cells. Furthermore, the increase in the expression of STAT6 and p-STAT6 induced by cisplatin was reversed by treatment with TSA, accompanied by the decreased expression of IL-1β, IL-4 and IL-6. Therefore, our data demonstrate that TSA reduces cisplatin-induced ototoxicity by inhibiting pro-inflammatory factor-mediated STAT6 signaling. Thus, TSA may be used to prevent the side-effects associated with the use of cisplatin in cancer treatment.
Collapse
Affiliation(s)
- Ji Huang
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, P.R. China
| | - Ping Wang
- Department of Otolaryngology-Head and Neck Surgery, The First Hospital of Jilin University, Changchun, Jilin, P.R. China
| | - Min Li
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, P.R. China
| | - Jingyan Ge
- Department of Physiology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, P.R. China
| | - Jiaqi Chen
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, P.R. China
| | - Xia Chen
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, P.R. China
| |
Collapse
|
17
|
Hu Y, Zhou LQ, Lu HT, Yuan K, Gong SS. Excitotoxic effects of glutamate on cochlear organotypic cultures. ACTA ACUST UNITED AC 2015; 35:117-121. [PMID: 25673204 DOI: 10.1007/s11596-015-1399-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 12/30/2014] [Indexed: 11/30/2022]
Abstract
Glutamate (Glu) is the major afferent excitatory neurotransmitter in the auditory system, and excessive Glu may play an important role in cochlear dysfunction. It is unclear how excessive Glu plays roles in cochlear dysfunction in cochlear organotypic cultures. In this study neonatal rat cochlear organotypic cultures were prepared, and then the cochlear tissues were incubated with a new medium containing specific concentrations of Glu (0.1, 0.5, 1, 10 or 20 mmol/L) for 24 h, or incubated with the medium containing a concentration of 20 mmol/L Glu for 6, 12, 24 or 72 h, respectively. It was found that when the cochlear tissues were cultured for 24 h, the inner hair cells (IHCs) were damaged at the concentration of 0.5 mmol/L Glu, and with the increases of the concentrations, the injury was gradually aggravated, and 20 mmol/L Glu resulted in the significant loss of IHCs. In the 20 mmol/L Glu groups, the stereocilia bundles were missing or disarrayed on a few IHCs after culture for 6 h and the damage effect was time-dependent. The missing of IHCs was more significant in the basal turn of the cochlea than in the middle turn of the cochlea under the same concentration of Glu exposure. These results suggest that excessive exogenous Glu affects the morphology of IHCs, but not affects the outer hair cells (OHCs) in cochlear organotypic cultures, and the excitotoxic effects are different on IHCs of different parts of the cochlea under the same concentration of Glu exposure.
Collapse
Affiliation(s)
- Yao Hu
- Department of Otolaryngology-Head and Neck Surgery, Wuhan Central Hospital, Wuhan, 430014, China
| | - Liu-Qing Zhou
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Hai-Tao Lu
- Department of Otorhinolaryngology, Jingzhou Central Hospital, Jingzhou, 434020, China
| | - Kun Yuan
- Department of Otolaryngology-Head and Neck Surgery, Wuhan Central Hospital, Wuhan, 430014, China.
| | - Shu-Sheng Gong
- Department of Otolaryngology-Head and Neck Surgery, Affiliated Beijing Tongren Hospital of Capital Medical University and Beijing Institute of Otolaryngology, Beijing, 100069, China.
| |
Collapse
|
18
|
Quan Y, Xia L, Shao J, Yin S, Cheng CY, Xia W, Gao WQ. Adjudin protects rodent cochlear hair cells against gentamicin ototoxicity via the SIRT3-ROS pathway. Sci Rep 2015; 5:8181. [PMID: 25640330 DOI: 10.1038/srep08181] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 12/18/2014] [Indexed: 12/15/2022] Open
Abstract
Hearing loss resulting from hair cell degeneration is a common disease that affects millions of people worldwide. Strategies to overcome the apparent irreversible hair cell loss in mammals become paramount for hearing protection. Here we reported that, by using a well-established gentamicin-induced hair cell loss model in vitro, adjudin, a multi-functional small molecule drug, protected cochlear hair cells from gentamicin damage. Immunohistochemistry, Western blotting and quantitative RT-PCR analyses revealed that adjudin exerted its otoprotective effects by up-regulating the level of Sirt3, a member of Sirtuin family protein located in mitochondria, which regulates reactive oxygen species (ROS) production in cochlear cells and inhibits the production of ROS and apoptotic cells induced by gentamicin. Sirt3 silencing experiments confirmed that Sirt3-ROS signaling axis mediated hair cell protection against gentamicin by adjudin, at least in part. Furthermore, adjudin's otoprotection effects were also observed in an in vivo gentamicin-injured animal model. Taken together, these findings identify adjudin as a novel otoprotective small molecule via elevating Sirt3 levels and Sirt3 may be of therapeutic value in hair cell protection from ototoxic insults.
Collapse
|
19
|
Lee JN, Kim SG, Lim JY, Kim SJ, Choe SK, Park R. Proteasome inhibitors induce auditory hair cell death through peroxisome dysfunction. Biochem Biophys Res Commun 2015; 456:269-74. [PMID: 25446082 DOI: 10.1016/j.bbrc.2014.11.070] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 11/18/2014] [Indexed: 11/21/2022]
Abstract
Even though bortezomib, a proteasome inhibitor, is a powerful chemotherapeutic agent used to treat multiple myeloma (MM) and other lymphoma cells, recent clinical reports suggest that the proteasome inhibitor therapy may be associated with severe bilateral hearing loss. We herein investigated the adverse effect of proteasome inhibitor on auditory hair cells. Treatment of a proteasome inhibitor destroys stereocilia bundles of hair cells resulting in the disarray of stereocilia in the organ of Corti explants. Since proteasome activity may be potentially important for biogenesis and function of the peroxisome, we tested whether proteasome activity is necessary for maintaining functional peroxisomes. Our results showed that treatment of a proteasome inhibitor significantly decreases both the number of peroxisomes and expression of peroxisomal proteins such as PMP70 and Catalase. In addition, we also found that proteasome inhibitor impairs the import pathway of PTS1-peroxisome matrix proteins. Taken together, our findings support recent clinical reports of hearing loss associated with proteasome inhibition. Mechanistically, peroxisome dysfunction may contribute to hair cell damage and hearing loss in response to the treatment of a proteasome inhibitor.
Collapse
|
20
|
Tropitzsch A, Arnold H, Bassiouni M, Müller A, Eckhard A, Müller M, Löwenheim H. Assessing cisplatin-induced ototoxicity and otoprotection in whole organ culture of the mouse inner ear in simulated microgravity. Toxicol Lett 2014; 227:203-12. [PMID: 24709139 DOI: 10.1016/j.toxlet.2014.03.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 03/25/2014] [Accepted: 03/27/2014] [Indexed: 12/20/2022]
Abstract
Cisplatin is a widely used anti-cancer drug. Ototoxicity is a major dose-limiting side-effect. A reproducible mammalian in-vitro model of cisplatin ototoxicity is required to screen and validate otoprotective drug candidates. We utilized a whole organ culture system of the postnatal mouse inner ear in a rotating wall vessel bioreactor under "simulated microgravity" culture conditions. As previously described this system allows whole organ culture of the inner ear and quantitative assessment of ototoxic effects of aminoglycoside induced hair cell loss. Here we demonstrate that this model is also applicable to the assessment of cisplatin induced ototoxicity. In this model cisplatin induced hair cell loss was dose and time dependent. Increasing exposure time of cisplatin led to decreasing EC50 concentrations. Outer hair cells were more susceptible than inner hair cells, and hair cells in the cochlear base were more susceptible than hair cells in the cochlear apex. Initial cisplatin dose determined the final extent of hair cell loss irrespective if the drug was withdrawn or continued. Dose dependant otoprotection was demonstrated by co-administration of the antioxidant agent N-acetyl l-cysteine. The results support the use of this inner ear organ culture system as an in vitro assay and validation platform for inner ear toxicology and the search for otoprotective compounds.
Collapse
Affiliation(s)
- Anke Tropitzsch
- University of Tübingen Medical School, Department of Otorhinolaryngology - Head & Neck Surgery, Hearing Research Center, Elfriede-Aulhorn-Straße 5, D-72076 Tübingen, Germany.
| | - Heinz Arnold
- University of Tübingen Medical School, Department of Otorhinolaryngology - Head & Neck Surgery, Hearing Research Center, Elfriede-Aulhorn-Straße 5, D-72076 Tübingen, Germany.
| | - Mohamed Bassiouni
- University of Tübingen Medical School, Department of Otorhinolaryngology - Head & Neck Surgery, Hearing Research Center, Elfriede-Aulhorn-Straße 5, D-72076 Tübingen, Germany.
| | - Andrea Müller
- University of Tübingen Medical School, Department of Otorhinolaryngology - Head & Neck Surgery, Hearing Research Center, Elfriede-Aulhorn-Straße 5, D-72076 Tübingen, Germany.
| | - Andreas Eckhard
- University of Tübingen Medical School, Department of Otorhinolaryngology - Head & Neck Surgery, Hearing Research Center, Elfriede-Aulhorn-Straße 5, D-72076 Tübingen, Germany.
| | - Marcus Müller
- University of Tübingen Medical School, Department of Otorhinolaryngology - Head & Neck Surgery, Hearing Research Center, Elfriede-Aulhorn-Straße 5, D-72076 Tübingen, Germany.
| | - Hubert Löwenheim
- University of Tübingen Medical School, Department of Otorhinolaryngology - Head & Neck Surgery, Hearing Research Center, Elfriede-Aulhorn-Straße 5, D-72076 Tübingen, Germany.
| |
Collapse
|
21
|
Yu Q, Chang Q, Liu X, Wang Y, Li H, Gong S, Ye K, Lin X. Protection of spiral ganglion neurons from degeneration using small-molecule TrkB receptor agonists. J Neurosci 2013; 33:13042-52. [PMID: 23926258 DOI: 10.1523/JNEUROSCI.0854-13.2013] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Neurotrophins (NTs) play essential roles in the development and survival of neurons in PNS and CNS. In the cochlea, NTs [e.g., NT-3, brain-derived neurotrophic factor (BDNF)] are required for the survival of spiral ganglion neurons (SGNs). Preservation of SGNs in the cochlea of patients suffering sensorineural deafness caused by loss of hair cells is needed for the optimal performance of the cochlear implant. Directly applying exogenous BDNF into the cochlea prevents secondary degeneration of SGNs when hair cells are lost. However, a common translational barrier for in vivo applications of BDNF is the poor pharmacokinetics, which severely limits the efficacy. Here we report that 7,8-dihydroxyflavone and 7,8,3'-trihydroxyflavone, both small-molecule agonists of tyrosine receptor kinase B (TrkB), promoted SGN survival with high potency both in vitro and in vivo. These compounds increased the phosphorylated TrkB and downstream MAPK and protected the SGNs in a TrkB-dependent manner. Their applications in the bulla of conditional connexin26 null mice offered significant protection for SGN survival. The function of survived SGNs was assessed by measuring evoked action potentials (APs) in vitro and electrically evoked auditory brainstem response (eABR) thresholds in vivo. APs were reliably evoked in cultured single SGNs treated with the compounds. In addition, eABR thresholds measured from the treated cochleae were significantly lower than untreated controls. Our findings suggest that these novel small-molecule TrkB agonists are promising in vivo therapeutic agents for preventing degeneration of SGNs.
Collapse
|
22
|
Yoo J, Hamilton SJ, Angel D, Fung K, Franklin J, Parnes LS, Lewis D, Venkatesan V, Winquist E. Cisplatin otoprotection using transtympanic L-N-acetylcysteine: a pilot randomized study in head and neck cancer patients. Laryngoscope 2013; 124:E87-94. [PMID: 23946126 DOI: 10.1002/lary.24360] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 07/17/2013] [Accepted: 07/22/2013] [Indexed: 11/10/2022]
Abstract
OBJECTIVES/HYPOTHESIS To evaluate the feasibility and efficacy of transtympanic L-N-Acetylcysteine (L-NAC) administration in patients receiving cisplatin chemotherapy for head and neck cancer. STUDY DESIGN Prospective randomized nonblinded open-label clinical trial. METHODS Transtympanic 2% L-NAC was administered to one randomly selected ear with the other ear as control in each patient. Primary outcome parameter was the difference in the loss of pure tone averages (PTA) at 2, 4, and 8 kHz between the L-NAC and control ear at 1 to 2 months following chemotherapy. RESULTS Eleven patients completed the study, with two patients demonstrating significantly better hearing in the L-NAC treated ear (18.2%). However, for the overall group, the difference in hearing preservation did not reach significance. Two percent L-NAC administration was well tolerated in this patient population. There were no adverse effects associated with L-NAC. CONCLUSION Although the study did not demonstrate a significant benefit overall, transtympanic L-NAC was associated with significantly better hearing in two patients. Better delivery methods may improve the efficacy of this treatment. L-NAC remains a promising drug in preventing cisplatin-induced ototoxicity.
Collapse
Affiliation(s)
- John Yoo
- Department of Audiology, London Health Sciences Centre, London, Ontario, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Wang P, Zhang P, Huang J, Li M, Chen X. Trichostatin A protects against cisplatin-induced ototoxicity by regulating expression of genes related to apoptosis and synaptic function. Neurotoxicology 2013; 37:51-62. [DOI: 10.1016/j.neuro.2013.03.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Revised: 03/10/2013] [Accepted: 03/18/2013] [Indexed: 11/25/2022]
|
24
|
Deng L, Ding D, Su J, Manohar S, Salvi R. Salicylate Selectively Kills Cochlear Spiral Ganglion Neurons by Paradoxically Up-regulating Superoxide. Neurotox Res 2013; 24:307-19. [DOI: 10.1007/s12640-013-9384-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 02/11/2013] [Accepted: 02/13/2013] [Indexed: 12/12/2022]
|
25
|
Kim SJ, Um JY, Kim SH, Hong SH. Protective effect of rosmarinic acid is through regulation of inflammatory cytokine in cadmium-induced ototoxicity. Am J Chin Med 2013; 41:391-404. [PMID: 23548128 DOI: 10.1142/s0192415x13500298] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Cadmium ( Cd(2+) ) is an environmental contaminant that causes a variety of adverse effects. Auditory cells are sensitive to cadmium, and the cochlea is more vulnerable to cadmium toxicity than the other parts of the auditory system. Rosmarinic acid (RA) exhibits a wide spectrum of biological activities, mainly antioxidant and anti-inflammatory activities. However, the regulatory effects of RA in the auditory system have not been elucidated. In this study, we investigated the protective effects of RA on Cd(2+) -induced ototoxicity in vitro and ex vivo. The findings showed that RA inhibited Cd(2+) -mediated cell toxicity, reactive oxygen species generation, interleukin (IL)-6 and IL-1β production, the translocation of the apoptosis inducing factor into the nucleus and activation of caspases-3 in an auditory cell line, HEI-OC1. In addition, RA prevented the destruction of hair cell arrays in the rat organ of Cortiprimary explants in the presence of Cd(2+) . These results are expected to improve our understanding of the pharmacological mechanism of RA, and help develop potential therapeutic strategies against ototoxicity.
Collapse
Affiliation(s)
- Su-Jin Kim
- Department of Cosmeceutical Science, Daegu Hanny University, Kyungsan 712-715, Republic of Korea
| | | | | | | |
Collapse
|
26
|
Abstract
Carboplatin, a second-generation platinum chemotherapeutic drug, is considerably less ototoxic than cisplatin. While common laboratory species such as mice, guinea pigs and rats are highly resistant to carboplatin ototoxicity, the chinchilla stands out as highly susceptible. Moreover, carboplatin causes an unusual gradient of cell death in chinchillas. Moderate doses selectively damage type I spiral ganglion neurons (SGN) and inner hair cells (IHC) and the lesion tends to be relatively uniform along the length of the cochlea. Higher doses eventually damage outer hair cells (OHC), but the lesion follows the traditional gradient in which damage is more severe in the base than the apex. While carboplatin ototoxicity has been well documented in adult animals in vivo, little is known about its in vitro toxicity. To elucidate the ototoxic effects of carboplatin in vitro, we prepared cochlear and vestibular organotypic cultures from postnatal day 3 rats and adult chinchillas. Chinchilla cochlear and vestibular cultures were treated with carboplatin concentrations ranging from 50 µM to 10 mM for 48 h. Consistent with in vivo data, carboplatin selectively damaged IHC at low concentrations (50-100 µM). Surprisingly, IHC loss decreased at higher doses and IHC were intact at doses exceeding 500 µM. The mechanisms underlying this nonlinear response are unclear but could be related to a decrease in carboplatin uptake via active transport mechanisms (e.g., copper). Unlike the cochlea, the carboplatin dose-response function increased with dose with the highest dose destroying all chinchilla vestibular hair cells. Cochlear hair cells and auditory nerve fibers in rat cochlear organotypic cultures were unaffected by carboplatin concentrations <10 µM; however, the damage in OHC were more severe than IHC once the dose reached 100 µM. A dose at 500 µM destroyed all the cochlear hair cells, but hair cell loss decreased at high concentrations and nearly all the cochlear hair cells were present at the highest dose, 5 mM. Unlike the nonlinear dose-response seen with cochlear hair cells, rat auditory nerve fiber and spiral ganglion losses increased with doses above 50 µM with the highest dose destroying virtually all SGN. The remarkable species differences seen in vitro suggest that chinchilla IHC and type I SGN posse some unique biological mechanism that makes them especially vulnerable to carboplatin toxicity.
Collapse
Affiliation(s)
- Ding Dalian
- Center for Hearing and Deafness, State University of New York at Buffalo ; Graduate School of Agricultural and Life Sciences, University of Tokyo
| | - Jiang Haiyan
- Center for Hearing and Deafness, State University of New York at Buffalo
| | - Fu Yong
- Center for Hearing and Deafness, State University of New York at Buffalo
| | - Richard Salvi
- Center for Hearing and Deafness, State University of New York at Buffalo
| | - Shinichi Someya
- Departments of Aging and Geriatric Research, Division of Biology of Aging, University of Florida
| | - Masaru Tanokura
- Graduate School of Agricultural and Life Sciences, University of Tokyo
| |
Collapse
|
27
|
Abstract
High doses of sodium salicylate (SS) have long been known to induce temporary hearing loss and tinnitus, effects attributed to cochlear dysfunction. However, our recent publications reviewed here show that SS can induce profound, permanent, and unexpected changes in the cochlea and central nervous system. Prolonged treatment with SS permanently decreased the cochlear compound action potential (CAP) amplitude in vivo. In vitro, high dose SS resulted in a permanent loss of spiral ganglion neurons and nerve fibers, but did not damage hair cells. Acute treatment with high-dose SS produced a frequency-dependent decrease in the amplitude of distortion product otoacoustic emissions and CAP. Losses were greatest at low and high frequencies, but least at the mid-frequencies (10-20 kHz), the mid-frequency band that corresponds to the tinnitus pitch measured behaviorally. In the auditory cortex, medial geniculate body and amygdala, high-dose SS enhanced sound-evoked neural responses at high stimulus levels, but it suppressed activity at low intensities and elevated response threshold. When SS was applied directly to the auditory cortex or amygdala, it only enhanced sound evoked activity, but did not elevate response threshold. Current source density analysis revealed enhanced current flow into the supragranular layer of auditory cortex following systemic SS treatment. Systemic SS treatment also altered tuning in auditory cortex and amygdala; low frequency and high frequency multiunit clusters up-shifted or down-shifted their characteristic frequency into the 10-20 kHz range thereby altering auditory cortex tonotopy and enhancing neural activity at mid-frequencies corresponding to the tinnitus pitch. These results suggest that SS-induced hyperactivity in auditory cortex originates in the central nervous system, that the amygdala potentiates these effects and that the SS-induced tonotopic shifts in auditory cortex, the putative neural correlate of tinnitus, arises from the interaction between the frequency-dependent losses in the cochlea and hyperactivity in the central nervous system.
Collapse
Affiliation(s)
- Guang-Di Chen
- Center for Hearing & Deafness, SUNY at Buffalo, 137 Cary Hall, Buffalo, NY 14214, USA.
| | | | | | | | | | | |
Collapse
|
28
|
Abstract
INTRODUCTION In the auditory system, a specialized subset of sensory neurons are responsible for correctly relaying precise pitch and temporal cues to the brain. In individuals with severe-to-profound sensorineural hearing impairment these sensory auditory neurons can be directly stimulated by a cochlear implant, which restores sound input to the brainstem after the loss of hair cells. This neural prosthesis therefore depends on a residual population of functional neurons in order to function effectively. AREAS COVERED In severe cases of sensorineural hearing loss where the numbers of auditory neurons are significantly depleted, the benefits derived from a cochlear implant may be minimal. One way in which to restore function to the auditory nerve is to replace these lost neurons using differentiated stem cells, thus re-establishing the neural circuit required for cochlear implant function. Such a therapy relies on producing an appropriate population of electrophysiologically functional neurons from stem cells, and on these cells integrating and reconnecting in an appropriate manner in the deaf cochlea. EXPERT OPINION Here we review progress in the field to date, including some of the key functional features that stem cell-derived neurons would need to possess and how these might be enhanced using electrical stimulation from a cochlear implant.
Collapse
Affiliation(s)
- Karina Needham
- University of Melbourne, Department of Otolaryngology, East Melbourne, Australia.
| | | | | | | |
Collapse
|
29
|
Kim SJ, Lee JH, Kim BS, So HS, Park R, Myung NY, Um JY, Hong SH. (-)-Epigallocatechin-3-gallate protects against NO-induced ototoxicity through the regulation of caspase- 1, caspase-3, and NF-κB activation. PLoS One 2012; 7:e43967. [PMID: 23028481 PMCID: PMC3461011 DOI: 10.1371/journal.pone.0043967] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Accepted: 07/30/2012] [Indexed: 12/16/2022] Open
Abstract
Excessive nitric oxide (NO) production is toxic to the cochlea and induces hearing loss. However, the mechanism through which NO induces ototoxicity has not been completely understood. The aim of this study was to gain further insight into the mechanism mediating NO-induced toxicity in auditory HEI-OC1 cells and in ex vivo analysis. We also elucidated whether and how epigallocatechin-3-gallate (EGCG), the main component of green tea polyphenols, regulates NO-induced auditory cell damage. To investigate NO-mediated ototoxicity, S-nitroso-N-acetylpenicillamine (SNAP) was used as an NO donor. SNAP was cytotoxic, generating reactive oxygen species, releasing cytochrome c, and activating caspase-3 in auditory cells. NO-induced ototoxicity also mediated the nuclear factor (NF)-κB/caspase-1 pathway. Furthermore, SNAP destroyed the orderly arrangement of the 3 outer rows of hair cells in the basal, middle, and apical turns of the organ of Corti from the cochlea of Sprague-Dawley rats at postnatal day 2. However, EGCG counteracted this ototoxicity by suppressing the activation of caspase-3/NF-κB and preventing the destruction of hair cell arrays in the organ of Corti. These findings may lead to the development of a model for pharmacological mechanism of EGCG and potential therapies against ototoxicity.
Collapse
Affiliation(s)
- Su-Jin Kim
- Department of Cosmeceutical Science, Daegu Hanny University, Kyungsan, Gyeoungbuk, Republic of Korea
| | - Jeong-Han Lee
- Center for Metabolic Function Regulation, Wonkwang University, Iksan, Republic of Korea
| | - Beom-Su Kim
- Wonkwang Bone Regeneration Research Institute, Wonkwang University, Iksan, Jeonbuk, Republic of Korea
| | - Hong-Seob So
- Center for Metabolic Function Regulation, Wonkwang University, Iksan, Republic of Korea
| | - Raekil Park
- Center for Metabolic Function Regulation, Wonkwang University, Iksan, Republic of Korea
| | - Noh-Yil Myung
- Center for Metabolic Function Regulation, Wonkwang University, Iksan, Republic of Korea
| | - Jae-Young Um
- College of Oriental Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Seung-Heon Hong
- Center for Metabolic Function Regulation, Wonkwang University, Iksan, Republic of Korea
| |
Collapse
|
30
|
Matt T, Ng CL, Lang K, Sha SH, Akbergenov R, Shcherbakov D, Meyer M, Duscha S, Xie J, Dubbaka SR, Perez-Fernandez D, Vasella A, Ramakrishnan V, Schacht J, Böttger EC. Dissociation of antibacterial activity and aminoglycoside ototoxicity in the 4-monosubstituted 2-deoxystreptamine apramycin. Proc Natl Acad Sci U S A 2012; 109:10984-9. [PMID: 22699498 PMCID: PMC3390888 DOI: 10.1073/pnas.1204073109] [Citation(s) in RCA: 152] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Aminoglycosides are potent antibacterials, but therapy is compromised by substantial toxicity causing, in particular, irreversible hearing loss. Aminoglycoside ototoxicity occurs both in a sporadic dose-dependent and in a genetically predisposed fashion. We recently have developed a mechanistic concept that postulates a key role for the mitochondrial ribosome (mitoribosome) in aminoglycoside ototoxicity. We now report on the surprising finding that apramycin, a structurally unique aminoglycoside licensed for veterinary use, shows little activity toward eukaryotic ribosomes, including hybrid ribosomes which were genetically engineered to carry the mitoribosomal aminoglycoside-susceptibility A1555G allele. In ex vivo cultures of cochlear explants and in the in vivo guinea pig model of chronic ototoxicity, apramycin causes only little hair cell damage and hearing loss but it is a potent antibacterial with good activity against a range of clinical pathogens, including multidrug-resistant Mycobacterium tuberculosis. These data provide proof of concept that antibacterial activity can be dissected from aminoglycoside ototoxicity. Together with 3D structures of apramycin-ribosome complexes at 3.5-Å resolution, our results provide a conceptual framework for further development of less toxic aminoglycosides by hypothesis-driven chemical synthesis.
Collapse
Affiliation(s)
- Tanja Matt
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
| | - Chyan Leong Ng
- Structural Studies Division, Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
| | - Kathrin Lang
- Structural Studies Division, Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
| | - Su-Hua Sha
- Kresge Hearing Research Institute, Department of Otolaryngology, Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109; and
| | - Rashid Akbergenov
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
| | - Dmitri Shcherbakov
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
| | - Martin Meyer
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
| | - Stefan Duscha
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
| | - Jing Xie
- Kresge Hearing Research Institute, Department of Otolaryngology, Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109; and
| | - Srinivas R. Dubbaka
- Laboratorium für Organische Chemie, Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland
| | - Déborah Perez-Fernandez
- Laboratorium für Organische Chemie, Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland
| | - Andrea Vasella
- Laboratorium für Organische Chemie, Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland
| | - V. Ramakrishnan
- Structural Studies Division, Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
| | - Jochen Schacht
- Kresge Hearing Research Institute, Department of Otolaryngology, Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109; and
| | - Erik C. Böttger
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
| |
Collapse
|
31
|
Yu Q, Chang Q, Liu X, Gong S, Ye K, Lin X. 7,8,3'-Trihydroxyflavone, a potent small molecule TrkB receptor agonist, protects spiral ganglion neurons from degeneration both in vitro and in vivo. Biochem Biophys Res Commun 2012; 422:387-92. [PMID: 22575512 DOI: 10.1016/j.bbrc.2012.04.154] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 04/30/2012] [Indexed: 01/07/2023]
Abstract
Most sensorineural hearing loss cases occur as a result of hair cell loss, which results in secondary degeneration of spiral ganglion neurons (SGNs). Substantial loss of SGNs reduces the benefit of cochlear implants, which rely on SGNs for transmitting signals to the central auditory centers. Brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) play essential roles in cochlear development and are required for SGN survival. Here we report that 7,8,3'-trihydroxyflavone (7,8,3'-THF), which is a small molecule agonist of tyrosine receptor kinase B (TrkB), promoted SGN survival with high potency both in vitro and in vivo. The compound protected the SGNs in a TrkB-dependent manner, as its effects on SGNs disappeared when the TrkB was blocked. Application of 7,8,3'-THF in the bulla of conditional connexin26 (cCx26)-null mice dramatically rescued SGNs in the applied ear compared to untreated control cochlea in the same animal. Our findings suggest that 7,8,3'-THF is a promising therapeutic agent protecting the SGNs from degeneration both in vitro and in vivo.
Collapse
Affiliation(s)
- Qing Yu
- Department of Otolaryngology Head & Neck Surgery, Beijing Tongren Hospital Capital Medical University, #1 Dong Jiao Min Xiang Street, Beijing 100730, China
| | | | | | | | | | | |
Collapse
|
32
|
Kim SJ, Myung NY, Shin BG, Lee JH, So HS, Park RK, Um JY, Hong SH. Protective Effect of a Chrysanthemum indicum containing Formulation in Cadmium-Induced Ototoxicity. Am J Chin Med 2012; 39:587-600. [DOI: 10.1142/s0192415x11009056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Chungshinchongyitang (CSCYT) is an herbal drug formula containing Chrysanthemum indicum and 13 other herbs used for treating auditory diseases. Irreversible hearing loss is a characteristic effect of a number of heavy metals. Cadmium ( Cd2+ ) is an environmental contaminant that causes a variety of adverse effects. In the present study, we investigate the protective effects of CSCYT against Cd2+ induced ototoxicity in vitro and ex vivo. The findings of this study show that CSCYT prevents the destruction of hair cell arrays induced by Cd2+ in the rat organ of Corti primary explants. CSCYT inhibited cell death, release of cytochrome c and generation of reactive oxygen species induced by Cd2+ in HEI-OC1 auditory cell line. In addition, we also demonstrated that CSCYT exerted its effect by modulating of apoptosis via the caspase-3 activation and extracellular signal-regulated kinase activation. These results are expected to improve the understanding of the pharmacological mechanism of CSCYT and aid in the development of potential therapeutic strategies against ototoxicity.
Collapse
Affiliation(s)
- Su-Jin Kim
- College of Oriental Medicine, Institute of Oriental Medicine Kyung Hee University, Seoul, 130-701, Republic of Korea
- VestibuloCochlear Research Center, Iksan, Jeonbuk, 570-749, Republic of Korea
- Department of Cosmeceutical Science, Daegu Hanny University, Republic of Korea
| | - Noh-Yil Myung
- VestibuloCochlear Research Center, Iksan, Jeonbuk, 570-749, Republic of Korea
| | - Bong-Gi Shin
- Wonkwang Oriental Medicines Research Institute, Department of Oriental Pharmacy, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea
| | - Jeong-Han Lee
- VestibuloCochlear Research Center, Iksan, Jeonbuk, 570-749, Republic of Korea
| | - Hong-Seob So
- VestibuloCochlear Research Center, Iksan, Jeonbuk, 570-749, Republic of Korea
| | - Rae-Kil Park
- VestibuloCochlear Research Center, Iksan, Jeonbuk, 570-749, Republic of Korea
| | - Jae-Young Um
- College of Oriental Medicine, Institute of Oriental Medicine Kyung Hee University, Seoul, 130-701, Republic of Korea
| | - Seung-Heon Hong
- VestibuloCochlear Research Center, Iksan, Jeonbuk, 570-749, Republic of Korea
- Wonkwang Oriental Medicines Research Institute, Department of Oriental Pharmacy, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea
| |
Collapse
|
33
|
KIM SUJIN, KWAK HYUNJEONG, KIM DAESEUNG, CHOI HYUNMYUNG, SIM JUNGEUN, KIM SUNGHOON, UM JAEYOUNG, HONG SEUNGHEON. Protective mechanism of Korean Red Ginseng in cisplatin-induced ototoxicity through attenuation of nuclear factor-κB and caspase-1 activation. Mol Med Rep 2012; 12:315-22. [DOI: 10.3892/mmr.2015.3396] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 01/27/2015] [Indexed: 11/06/2022] Open
|
34
|
Rhee CK, He P, Jung JY, Ahn JC, Chung PS, Suh MW. Effect of low-level laser therapy on cochlear hair cell recovery after gentamicin-induced ototoxicity. Lasers Med Sci 2011; 27:987-92. [PMID: 22138884 DOI: 10.1007/s10103-011-1028-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Accepted: 10/28/2011] [Indexed: 10/14/2022]
Abstract
Cochlear hair cells are the sensory receptors of the auditory system. It is well established that antibiotic drugs such as gentamicin can damage hair cells and cause hearing loss. Rescuing hair cells after ototoxic injury is an important issue in hearing recovery. Although many studies have indicated a positive effect of low-level laser therapy (LLLT) on neural cell survival, there has been no study on the effects of LLLT on cochlear hair cells. Therefore, the aim of this study was to elucidate the effects of LLLT on hair cell survival following gentamicin exposure in organotypic cultures of the cochlea of rats. The cochlea cultures were then divided into a control group (n = 8), a laser-only group (n = 8), a gentamicin-only group (n = 8) and a gentamicin plus laser group (n = 7). The control cultures were allowed to grow continuously for 11 days. The laser-only cultures were irradiated with a laser with a wavelength of 810 nm at 8 mW/cm(2) for 60 min per day (0.48 J/cm(2)) for 6 days. The gentamicin groups were exposed to 1 mM gentamicin for 48 h and allowed to recover (gentamicin-only group) or allowed to recover with daily irradiation (gentamicin plus laser group). The hair cells in all groups were stained with FM1-43 and counted every 3 days. The number of hair cells was significantly larger in the gentamicin plus laser group than in the gentamicin-only group. The number of hair cells was larger in the laser-only group than in the control group, but the difference did not reach statistical significance. These results suggest that LLLT may promote hair cell survival following gentamicin damage in the cochlea. This is the first study in the literature that has demonstrated the beneficial effect of LLLT on the recovery of cochlear hair cells.
Collapse
Affiliation(s)
- Chung-Ku Rhee
- Department of Otolaryngology-Head & Neck Surgery, Dankook University College of Medicine, Cheonan, Korea
| | | | | | | | | | | |
Collapse
|
35
|
Abstract
In mammals, the initial bridge between the physical world of sound and perception of that sound is established by neurons of the spiral ganglion. The cell bodies of these neurons give rise to peripheral processes that contact acoustic receptors in the organ of Corti, and the central processes collect together to form the auditory nerve that projects into the brain. In order to better understand hearing at this initial stage, we need to know the following about spiral ganglion neurons: (1) their cell biology including cytoplasmic, cytoskeletal, and membrane properties, (2) their peripheral and central connections including synaptic structure; (3) the nature of their neural signaling; and (4) their capacity for plasticity and rehabilitation. In this report, we will update the progress on these topics and indicate important issues still awaiting resolution.
Collapse
Affiliation(s)
- Bryony A Nayagam
- Department of Otolaryngology, University of Melbourne, Melbourne, VIC Australia
| | - Michael A Muniak
- Department of Neuroscience, Johns Hopkins University, Baltimore, MD USA
| | - David K Ryugo
- Department of Neuroscience, Johns Hopkins University, Baltimore, MD USA
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University, Baltimore, MD USA
- Garvan Institute, Darlinghurst, NSW Australia
| |
Collapse
|
36
|
Lu J, Lobarinas E, Deng A, Goodey R, Stolzberg D, Salvi RJ, Sun W. GABAergic neural activity involved in salicylate-induced auditory cortex gain enhancement. Neuroscience 2011; 189:187-98. [PMID: 21664433 DOI: 10.1016/j.neuroscience.2011.04.073] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Revised: 04/12/2011] [Accepted: 04/16/2011] [Indexed: 12/31/2022]
Abstract
Although high doses of sodium salicylate impair cochlear function, it paradoxically enhances sound-evoked activity in the auditory cortex (AC) and augments acoustic startle reflex responses, neural and behavioral metrics associated with hyperexcitability and hyperacusis. To explore the neural mechanisms underlying salicylate (SS)-induced hyperexcitability and "increased central gain," we examined the effects of GABA receptor agonists and antagonists on SS-induced hyperexcitability in the AC and startle reflex responses. Consistent with our previous findings, local or systemic application of SS significantly increased the amplitude of sound-evoked AC neural activity, but generally reduced spontaneous activity in the AC. Systemic injection of SS also significantly increased the acoustic startle reflex. S-baclofen or R-baclofen, GABA-B agonists, which suppressed sound-evoked AC neural firing rate and local field potentials, also suppressed the SS-induced enhancement of the AC field potential and the acoustic startle reflex. Local application of vigabatrin, which enhances GABA concentration in the brain, suppressed the SS-induced enhancement of AC firing rate. Systemic injection of vigabatrin also reduced the SS-induced enhancement of acoustic startle reflex. Collectively, these results suggest that the sound-evoked behavioral and neural hyperactivity induced by SS may arise from a SS-induced suppression of GABAergic inhibition in the AC.
Collapse
Affiliation(s)
- J Lu
- Center for Hearing and Deafness, Department of Communicative Disorders and Sciences, State University of New York at Buffalo, 3435 Main Street, NY 14214, USA
| | | | | | | | | | | | | |
Collapse
|
37
|
Leake PA, Hradek GT, Hetherington AM, Stakhovskaya O. Brain-derived neurotrophic factor promotes cochlear spiral ganglion cell survival and function in deafened, developing cats. J Comp Neurol 2011; 519:1526-45. [PMID: 21452221 PMCID: PMC3079794 DOI: 10.1002/cne.22582] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Postnatal development and survival of spiral ganglion (SG) neurons depend on both neural activity and neurotrophic support. Our previous studies showed that electrical stimulation from a cochlear implant only partially prevents SG degeneration after early deafness. Thus, neurotrophic agents that might be combined with an implant to improve neural survival are of interest. Recent studies reporting that brain-derived neurotrophic factor (BDNF) promotes SG survival after deafness have been conducted in rodents and limited to relatively short durations. Our study examined longer duration BDNF treatment in deafened cats that may better model the slow progression of SG degeneration in human cochleae, and this is the first study of BDNF in the developing auditory system. Kittens were deafened neonatally, implanted at 4-5 weeks with intracochlear electrodes containing a drug-delivery cannula, and BDNF or artificial perilymph was infused for 10 weeks from a miniosmotic pump. In BDNF-treated cochleae, SG cells grew to normal size and were significantly larger than cells on the contralateral side. However, their morphology was not completely normal, and many neurons lacked or had thinned perikaryl myelin. Unbiased stereology was employed to estimate SG cell density, independent of cell size. BDNF was effective in promoting significantly improved survival of SG neurons in these developing animals. BDNF treatment also resulted in higher density and larger size of myelinated radial nerve fibers, sprouting of fibers into the scala tympani, and improvement of electrically evoked auditory brainstem response thresholds. BDNF may have potential therapeutic value in the developing auditory system, but many serious obstacles currently preclude clinical application.
Collapse
Affiliation(s)
- Patricia A Leake
- Departmant of Otolaryngology-Head and Neck Surgery, University of California San Francisco, San Francisco, California 94143-0526, USA.
| | | | | | | |
Collapse
|
38
|
Oh GS, Kim HJ, Choi JH, Shen A, Kim CH, Kim SJ, Shin SR, Hong SH, Kim Y, Park C, Lee SJ, Akira S, Park R, So HS. Activation of lipopolysaccharide-TLR4 signaling accelerates the ototoxic potential of cisplatin in mice. J Immunol 2010; 186:1140-50. [PMID: 21148032 DOI: 10.4049/jimmunol.1002183] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Dysfunction in immune surveillance during anticancer chemotherapy of patients often causes weakness of the host defense system and a subsequent increase in microbial infections. However, the deterioration of organ-specific function related to microbial challenges in cisplatin-treated patients has not yet been elucidated. In this study, we investigated cisplatin-induced TLR4 expression and its binding to LPS in mouse cochlear tissues and the effect of this interaction on hearing function. Cisplatin increased the transcriptional and translational expression of TLR4 in the cochlear tissues, organ of Corti explants, and HEI-OC1 cells. Furthermore, cisplatin increased the interaction between TLR4 and its microbial ligand LPS, thereby upregulating the production of proinflammatory cytokines, such as TNF-α, IL-1β, and IL-6, via NF-κB activation. In C57BL/6 mice, the combined injection of cisplatin and LPS caused severe hearing impairment compared with that in the control, cisplatin-alone, or LPS-alone groups, whereas this hearing dysfunction was completely suppressed in both TLR4 mutant and knockout mice. These results suggest that hearing function can be easily damaged by increased TLR expression and microbial infections due to the weakened host defense systems of cancer patients receiving therapy comprising three to six cycles of cisplatin alone or cisplatin combined with other chemotherapeutic agents. Moreover, such damage can occur even though patients may not experience ototoxic levels of cumulative cisplatin concentration.
Collapse
Affiliation(s)
- Gi-Su Oh
- Vestibulocochlear Research Center, Wonkwang University School of Medicine, Iksan, Jeonbuk 570-749, Republic of Korea
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Feng H, Yin SH, Tang AZ, Cai HW, Chen P, Tan SH, Xie LH. Caspase-3 activation in the guinea pig cochlea exposed to salicylate. Neurosci Lett 2010; 479:34-9. [PMID: 20478357 DOI: 10.1016/j.neulet.2010.05.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Revised: 04/27/2010] [Accepted: 05/08/2010] [Indexed: 12/19/2022]
Abstract
In the current study, we explored whether chronic salicylate exposure could induce apoptosis in outer hair cells (OHCs) and spiral ganglion neurons (SGNs) of the cochlea. Guinea pig received sodium salicylate (400 mg/kg/d) or saline vehicle for 10 consecutive days. Programmed cell death (PCD) executioner was evaluated with immunohistochemistry detection of activated caspase-3. Apoptosis was examined with a terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method. Repeated salicylate administration activated caspase-3 and caused apoptosis in OHCs and SGNs (p<0.01 vs. saline control for both measures and in both cell types). Cell counting showed a significant loss in OHCs (p<0.01 vs. saline control), but not in inner hair cells (IHCs). Transmission electron microscopy (TEM) revealed chromatin condensation and nucleus margination in salicylate-treated cochlea. Scanning electron microscopy (SEM) demonstrated stereociliary bundles breakdown and fusion at the apical of OHCs, villous matter was discovered to attach on the surface of SGNs. These findings suggest that long-term administration of high-dose salicylate can activate caspase-3 pathway to induce OHC and SGN apoptosis.
Collapse
Affiliation(s)
- Hao Feng
- Department of Otorhinolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, PR China
| | | | | | | | | | | | | |
Collapse
|
40
|
Palmgren B, Jin Z, Ma H, Jiao Y, Olivius P. beta-Bungarotoxin application to the round window: an in vivo deafferentation model of the inner ear. Hear Res 2010; 265:70-6. [PMID: 20184947 DOI: 10.1016/j.heares.2010.02.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Revised: 02/13/2010] [Accepted: 02/18/2010] [Indexed: 10/19/2022]
Abstract
Hearing impairment can be caused by a primary lesion to the spiral ganglion neurons (SGNs) with the hair cells kept intact, for example via tumours, trauma or auditory neuropathy. To mimic these conditions in animal models various methods of inflicting damage to the inner ear have been used. However, only a few methods have a selective effect on the SGNs, which is of importance since it might be clinically more relevant to study hearing impairment with the hair cells undamaged. beta-Bungarotoxin is a venom of the Taiwan banded krait, which in vitro has been shown to induce apoptosis in neurons, leaving remaining cochlear cells intact. We wanted to create an in vivo rat model of selective damage to primary auditory neurons. Under deep anaesthesia, 41 rats received beta-Bungarotoxin or saline to the round window niche. At postoperative intervals between days 3 and 21 auditory brainstem response (ABR) measurement, immunohistochemistry, SGN quantification and cochlear surface preparation were performed. The results in the beta-Bungarotoxin-treated ears, as compared with sham-operated ears, show significantly increased ABR thresholds at all postoperative intervals, illustrating a severe to profound hearing loss at all tested frequencies (3.5, 7, 16 and 28 kHz). Quantification of the SGNs showed no obvious reduction in neuronal numbers until 14 days postoperatively. Between days 14 and 21 a significant reduction in SGN numbers was observed. Cochlear surface preparation and immunohistochemistry showed that the hair cells were intact. Our results illustrate that in vivo application of beta-Bungarotoxin to the round window niche is a feasible way of deafening rats by SGN reduction while the hair cells are kept intact.
Collapse
Affiliation(s)
- Björn Palmgren
- Center for Hearing and Communication Research, Karolinska University Hospital, 171 76 Stockholm, Sweden.
| | | | | | | | | |
Collapse
|
41
|
Abstract
In all mammals, the sensory epithelium for audition is located along the spiraling organ of Corti that resides within the conch shaped cochlea of the inner ear (fig 1). Hair cells in the developing cochlea, which are the mechanosensory cells of the auditory system, are aligned in one row of inner hair cells and three (in the base and mid-turns) to four (in the apical turn) rows of outer hair cells that span the length of the organ of Corti. Hair cells transduce sound-induced mechanical vibrations of the basilar membrane into neural impulses that the brain can interpret. Most cases of sensorineural hearing loss are caused by death or dysfunction of cochlear hair cells. An increasingly essential tool in auditory research is the isolation and in vitro culture of the organ explant. Once isolated, the explants may be utilized in several ways to provide information regarding normative, anomalous, or therapeutic physiology. Gene expression, stereocilia motility, cell and molecular biology, as well as biological approaches for hair cell regeneration are examples of experimental applications of organ of Corti explants. This protocol describes a method for the isolation and culture of the organ of Corti from neonatal mice. The accompanying video includes stepwise directions for the isolation of the temporal bone from mouse pups, and subsequent isolation of the cochlea, spiral ligament, and organ of Corti. Once isolated, the sensory epithelium can be plated and cultured in vitro in its entirety, or as a further dissected micro-isolate that lacks the spiral limbus and spiral ganglion neurons. Using this method, primary explants can be maintained for 7-10 days. As an example of the utility of this procedure, organ of Corti explants will be electroporated with an exogenous DsRed reporter gene. This method provides an improvement over other published methods because it provides reproducible, unambiguous, and stepwise directions for the isolation, microdissection, and primary culture of the organ of Corti.
Collapse
Affiliation(s)
- Mark Parker
- Department of Otology and Laryngology, Harvard Medical School, USA.
| | | | | |
Collapse
|
42
|
Park H, Kim H, Bae G, Seo S, Kim D, Jung W, Kim M, Song M, Kim E, Kwon K, Hwang S, Song H, Park C, Park R, Chong M, Park S. Selective GSK-3β inhibitors attenuate the cisplatin-induced cytotoxicity of auditory cells. Hear Res 2009; 257:53-62. [DOI: 10.1016/j.heares.2009.08.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Revised: 07/31/2009] [Accepted: 08/01/2009] [Indexed: 12/20/2022]
|
43
|
Abstract
Cisplatin is a chemotherapeutic agent that is widely used to treat a variety of malignant tumors. Serious dose-limiting side effects like ototoxicity, nephrotoxicity and neurotoxicity occur with the use of this agent. This review summarizes recent important clinical and experimental investigations of cisplatin ototoxicity. It also discusses the utility of protective agents employed in patients and in experimental animals. The future strategies for limiting cisplatin ototoxicity will need to avoid interference with the therapeutic effect of cisplatin in order to enhance the quality of life of patients receiving this important anti-tumor agent.
Collapse
Affiliation(s)
- Leonard P Rybak
- Department of Surgery, Southern Illinois University School of Medicine, IL, USA.
| | | | | | | |
Collapse
|
44
|
Lossi L, Alasia S, Salio C, Merighi A. Cell death and proliferation in acute slices and organotypic cultures of mammalian CNS. Prog Neurobiol 2009; 88:221-45. [DOI: 10.1016/j.pneurobio.2009.01.002] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Revised: 12/09/2008] [Accepted: 01/07/2009] [Indexed: 11/24/2022]
|
45
|
Kim SJ, Park C, Han AL, Youn MJ, Lee JH, Kim Y, Kim ES, Kim HJ, Kim JK, Lee HK, Chung SY, So H, Park R. Ebselen attenuates cisplatin-induced ROS generation through Nrf2 activation in auditory cells. Hear Res 2009; 251:70-82. [DOI: 10.1016/j.heares.2009.03.003] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2008] [Revised: 02/28/2009] [Accepted: 03/04/2009] [Indexed: 01/27/2023]
|
46
|
Abstract
Post-translational modification of histones is an important form of chromatin regulation impacting transcriptional activation. Histone acetyltransferases, for example, acetylate lysine residues on histone tails thereby enhancing gene transcription, while histone deacetylases (HDACs) remove those acetyl groups and repress gene transcription. Deficient histone acetylation is associated with pathologies, and histone deacetylase inhibitors have been studied in the treatment of cancer and neurodegenerative diseases. Here we explore histone acetylation in cochlear sensory cells following a challenge with gentamicin, an aminoglycoside antibiotic known to cause loss of auditory hair cells and hearing. The addition of the drug to organotypic cultures of the mouse organ of Corti decreased the acetylation of histone core proteins (H2A Ack5, H2B Ack12, H3 Ack9, and H4 Ack8) followed by a loss of sensory cells. Protein levels of HDAC1, HDAC3 and HDAC4 were increased while the histone acetyltransferases such as CREB-binding protein and p300 remained unchanged. We next hypothesized that protecting histone acetylation should prevent cell death and tested the effects of HDAC-inhibitors on the actions of gentamicin. Co-treatment with trichostatin A maintained near-normal levels of acetylation of histone core proteins in cochlear hair cells and attenuated gentamicin-induced cell death. The addition of sodium butyrate also rescued hair cells from damage by gentamicin. The results are consistent with an involvement of deficient histone acetylation in aminoglycoside-induced hair cell death and point to the potential value of HDAC-inhibitors in protection from the side effects of these drugs.
Collapse
Affiliation(s)
- Fu-Quan Chen
- Kresge Hearing Research Institute, Department of Otolaryngology, University of Michigan, Ann Arbor, USA
| | | | | |
Collapse
|
47
|
Kim SJ, Shin BG, Choi IY, Kim DH, Kim MC, Myung NY, Moon PD, Lee JH, An HJ, Kim NH, Lee JY, So HS, Park RK, Jeong HJ, Um JY, Kim HM, Hong SH. Hwanggunchungyitang Prevents Cadmium-Induced Ototoxicity through Suppression of the Activation of Caspase-9 and Extracellular Signal-Related Kinase in Auditory HEI-OC1 Cells. Biol Pharm Bull 2009; 32:213-9. [DOI: 10.1248/bpb.32.213] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Su-Jin Kim
- VestibuloCochlear Research Center of Wonkwang University
- College of Oriental Medicine, Kyung Hee University
| | - Bong-Gi Shin
- VestibuloCochlear Research Center of Wonkwang University
| | - In-Young Choi
- VestibuloCochlear Research Center of Wonkwang University
| | - Dong-Hyun Kim
- VestibuloCochlear Research Center of Wonkwang University
| | - Min-cheol Kim
- VestibuloCochlear Research Center of Wonkwang University
| | - Noh-Yil Myung
- Acupuncture and Meridian Science Research Center, Kyung Hee University
| | | | - Jeong-Han Lee
- VestibuloCochlear Research Center of Wonkwang University
| | - Hyo-Jin An
- College of Oriental Medicine, Kyung Hee University
| | - Na-Hyung Kim
- College of Oriental Medicine, Kyung Hee University
| | | | - Hong-seob So
- VestibuloCochlear Research Center of Wonkwang University
| | - Rae-Kil Park
- VestibuloCochlear Research Center of Wonkwang University
| | | | - Jae-Young Um
- Acupuncture and Meridian Science Research Center, Kyung Hee University
- College of Oriental Medicine, Kyung Hee University
| | | | - Seung-Heon Hong
- VestibuloCochlear Research Center of Wonkwang University
- Department of Oriental Pharmacy, College of Pharmacy, Wonkwang University
| |
Collapse
|
48
|
Leake PA, Stakhovskaya O, Hradek GT, Hetherington AM. Factors influencing neurotrophic effects of electrical stimulation in the deafened developing auditory system. Hear Res 2008; 242:86-99. [PMID: 18573324 PMCID: PMC2516744 DOI: 10.1016/j.heares.2008.06.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Revised: 05/21/2008] [Accepted: 06/02/2008] [Indexed: 02/01/2023]
Abstract
Research in animal models has demonstrated that electrical stimulation from a cochlear implant (CI) may help prevent degeneration of the cochlear spiral ganglion (SG) neurons after deafness. In cats deafened early in life, effective stimulation of the auditory nerve with complex signals for several months preserves a greater density of SG neurons in the stimulated cochleae as compared to the contralateral deafened ear. However, SG survival is still far from normal even with early intervention with an implant. Thus, pharmacologic agents and neurotrophic factors that might be used in combination with an implant are of great interest. Exogenous administration of GM1 ganglioside significantly reduces SG degeneration in deafened animals studied at 7-8 weeks of age, but after several months of stimulation, GM1-treated animals show only modestly better preservation of SG density compared to age-matched non-treated animals. A significant factor influencing neurotrophic effects in animal models is insertion trauma, which results in significant regional SG degeneration. Thus, an important goal is to further improve human CI electrode designs and insertion techniques to minimize trauma. Another important issue for studies of neurotrophic effects in the developing auditory system is the potential role of critical periods. Studies examining animals deafened at 30 days of age (rather than at birth) have explored whether a brief initial period of normal auditory experience affects the vulnerability of the SG or cochlear nucleus (CN) to auditory deprivation. Interestingly, SG survival in animals deafened at 30-days was not significantly different from age-matched neonatally deafened animals, but significant differences were observed in the central auditory system. CN volume was significantly closer to normal in the animals deafened at 30 days as compared to neonatally deafened animals. However, no difference was observed between the stimulated and contralateral CN volumes in either deafened group. Measurements of AVCN spherical cell somata showed that after later onset of deafness in the 30-day deafened group, mean cell size was significantly closer to normal than in the neonatally deafened group. Further, electrical stimulation elicited a significant increase in spherical cell size in the CN ipsilateral to the implant as compared to the contralateral CN in both deafened groups. Neuronal tracer studies have examined the primary afferent projections from the SG to the CN in neonatally deafened cats. CN projections exhibit a clear cochleotopic organization despite severe auditory deprivation from birth. However, when normalized for the smaller CN size after deafness, projections were 30-50% broader than normal. After unilateral electrical stimulation there was no difference between projections from the stimulated and non-stimulated ears. These findings suggest that early normal auditory experience may be essential for the normal development (or subsequent maintenance) of the topographic precision of SG-to-CN projections. After early deafness, the CN volume is markedly smaller than normal, and the spatial precision of SG projections that underlie frequency resolution in the central auditory system is reduced. Electrical stimulation over several months did not reduce or exacerbate these degenerative changes. If similar principles pertain in the human auditory system, then findings in animal models suggest that the basic cochleotopic organization of neural projections in the central auditory system is probably intact even in congenitally deaf individuals. However, the reduced spatial resolution of the primary afferent projections in our studies suggests that there may be inherent limitations for CI stimulation in congenitally deaf subjects. Spatial (spectral) selectivity of stimulation delivered on adjacent CI channels may be poorer due to the greater overlap of SG central axons representing nearby frequencies. Such CI users may be more dependent upon temporal features of electrical stimuli, and it may be advantageous to enhance the salience of such cues, for example, by removing some electrodes from the processor "map" to reduce channel interaction.
Collapse
Affiliation(s)
- Patricia A Leake
- Epstein Hearing Research Laboratory, Department of Otolaryngology-Head and Neck Surgery, University of California San Francisco, 533 Parnassus Avenue, Room U490, San Francisco, CA 94143-0526, United States.
| | | | | | | |
Collapse
|
49
|
Kim SJ, Jeong HJ, Myung NY, Kim MC, Lee JH, So HS, Park RK, Kim HM, Um JY, Hong SH. The protective mechanism of antioxidants in cadmium-induced ototoxicity in vitro and in vivo. Environ Health Perspect 2008; 116:854-62. [PMID: 18629305 PMCID: PMC2453151 DOI: 10.1289/ehp.10467] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Accepted: 02/25/2008] [Indexed: 05/20/2023]
Abstract
BACKGROUND Several heavy metals have been shown to have toxic effects on the peripheral and central auditory system. Cadmium (Cd2+) is an environmental contaminant showing a variety of adverse effects. Given the current rate of release into the environment, the amount of Cd2+ present in the human body and the incidence of Cd2+-related diseases are expected to increase. OBJECTIVE The overall aim of this study was to gain further insights into the mechanism of Cd2+-induced ototoxicity. METHODS Cell viability, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), cytochrome c (cyt c), phosphorylated extracellular signal-regulated protein kinase (p-ERK), caspases, morphologic change, and functional changes in HEI-OC1 cells, rat cochlear explants, and mouse cochlea after Cd2+ exposure were measured by flow cytometry, immunohistochemical staining, Western blot analysis, and auditory brainstem response (ABR) recording. Mechanisms underlying Cd2+ototoxicity were studied using inhibitors of different signaling pathways, caspases, and antioxidants. RESULTS Cd2+ exposure caused cell death, ROS generation, MMP loss, cyt c release, activation of caspases, ERK activation, apoptosis, and finally auditory threshold shift. Cd2+ toxicity interfered with inhibitors of cellular signaling pathways, such as ERK and c-jun N-terminal kinase, and with caspase inhibitors, especially inhibitors of caspase-9 and caspase-3. The antioxidants N-acetyl-l-cysteine and ebselen showed a significant protective effect on the Cd2+ toxicity. CONCLUSIONS Cd2+ is ototoxic with a complex underlying mechanism. However, ROS generation may be the cause of the toxicity, and application of antioxidants can prevent the toxic effect.
Collapse
Affiliation(s)
- Su-Jin Kim
- College of Oriental Medicine, Kyung Hee University, Hoegi-Dong, Dongdaemun-Gu, Seoul, Republic of Korea
- Vestibulocochlear Research Center of Wonkwang University, Iksan, Jeonbuk, Republic of Korea
| | - Hyun-Ja Jeong
- College of Oriental Medicine, Kyung Hee University, Hoegi-Dong, Dongdaemun-Gu, Seoul, Republic of Korea
- Vestibulocochlear Research Center of Wonkwang University, Iksan, Jeonbuk, Republic of Korea
| | - Noh-Yil Myung
- College of Oriental Medicine, Kyung Hee University, Hoegi-Dong, Dongdaemun-Gu, Seoul, Republic of Korea
- Vestibulocochlear Research Center of Wonkwang University, Iksan, Jeonbuk, Republic of Korea
| | - Min-chol Kim
- Vestibulocochlear Research Center of Wonkwang University, Iksan, Jeonbuk, Republic of Korea
| | - Jeong-Han Lee
- Vestibulocochlear Research Center of Wonkwang University, Iksan, Jeonbuk, Republic of Korea
| | - Hong-seob So
- Vestibulocochlear Research Center of Wonkwang University, Iksan, Jeonbuk, Republic of Korea
| | - Rae-Kil Park
- Vestibulocochlear Research Center of Wonkwang University, Iksan, Jeonbuk, Republic of Korea
| | - Hyung-Min Kim
- College of Oriental Medicine, Kyung Hee University, Hoegi-Dong, Dongdaemun-Gu, Seoul, Republic of Korea
| | - Jae-Young Um
- College of Oriental Medicine, Kyung Hee University, Hoegi-Dong, Dongdaemun-Gu, Seoul, Republic of Korea
| | - Seung-Heon Hong
- Vestibulocochlear Research Center of Wonkwang University, Iksan, Jeonbuk, Republic of Korea
| |
Collapse
|
50
|
Hahn H, Müller M, Löwenheim H. Whole organ culture of the postnatal sensory inner ear in simulated microgravity. J Neurosci Methods 2008; 171:60-71. [PMID: 18440073 DOI: 10.1016/j.jneumeth.2008.02.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2007] [Revised: 01/16/2008] [Accepted: 02/04/2008] [Indexed: 11/23/2022]
Abstract
Among the three major biological in vitro models, cell culture, tissue culture, and organ culture, the latter provides the closest approximation to the in vivo situation, but also requires the most demanding culture conditions. Due to its small size and complex tissue architecture, the mammalian inner ear provides a particular challenge to the development of whole organ culture. Using a rotating bioreactor system with simulated microgravity conditions, the entire mouse inner ear organ can be maintained in culture for up to seven days with preservation of sensory organ morphology and robust marker protein expression in sensory hair cells. Controlled sensory cell lesions can be induced by the ototoxic agent, neomycin sulphate, as a toxicologic model of hair cell degeneration and hair cell loss. The results demonstrate that simulated microgravity organ culture of the inner ear affords an in vitro model for the investigation of developmental, regulatory, and differentiation processes, as well as toxicological, biotechnological, and pharmaceutical screening applications within the normal and pathologic sensory hearing organ.
Collapse
|