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Soares M, Santos ABD, Weich TM, Mânica GG, Homem de Bittencourt PI, Ludwig MS, Heck TG. Heat shock response in noise-induced hearing loss: effects of alanyl-glutamine dipeptide supplementation on heat shock proteins status. Braz J Otorhinolaryngol 2020; 86:703-710. [PMID: 31255578 PMCID: PMC9422582 DOI: 10.1016/j.bjorl.2019.04.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 03/30/2019] [Accepted: 04/17/2019] [Indexed: 02/07/2023] Open
Abstract
Introduction Objective Methods Results Conclusions
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Affiliation(s)
- Marcos Soares
- Universidade Regional do Noroeste do Estado do Rio Grande do Sul (Unijuí), Departamento de Ciências da Vida, Programa de Pós-Graduação em Atenção Integral à Saúde, Ijuí, RS, Brazil.
| | - Analu B Dos Santos
- Universidade Regional do Noroeste do Estado do Rio Grande do Sul (Unijuí), Departamento de Ciências da Vida, Programa de Pós-Graduação em Atenção Integral à Saúde, Ijuí, RS, Brazil
| | - Tainara M Weich
- Universidade Regional do Noroeste do Estado do Rio Grande do Sul (Unijuí), Departamento de Ciências da Vida, Programa de Pós-Graduação em Atenção Integral à Saúde, Ijuí, RS, Brazil
| | - Gabriela Gomes Mânica
- Universidade Regional do Noroeste do Estado do Rio Grande do Sul (Unijuí), Departamento de Ciências da Vida, Programa de Pós-Graduação em Atenção Integral à Saúde, Ijuí, RS, Brazil
| | - Paulo Ivo Homem de Bittencourt
- Universidade Federal do Rio Grande do Sul, Instituto de Ciências Básicas da Saúde, Departamento de Fisiologia, Porto Alegre, RS, Brazil
| | - Mirna Stela Ludwig
- Universidade Regional do Noroeste do Estado do Rio Grande do Sul (Unijuí), Departamento de Ciências da Vida, Programa de Pós-Graduação em Atenção Integral à Saúde, Ijuí, RS, Brazil
| | - Thiago Gomes Heck
- Universidade Regional do Noroeste do Estado do Rio Grande do Sul (Unijuí), Departamento de Ciências da Vida, Programa de Pós-Graduação em Atenção Integral à Saúde, Ijuí, RS, Brazil.
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Dugan EA, Bennett C, Tamames I, Dietrich WD, King CS, Prasad A, Rajguru SM. Therapeutic hypothermia reduces cortical inflammation associated with utah array implants. J Neural Eng 2020; 17:026035. [PMID: 32240985 DOI: 10.1088/1741-2552/ab85d2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Neuroprosthetics hold tremendous promise to restore function through brain-computer interfaced devices. However, clinical applications of implantable microelectrodes remain limited given the challenges of maintaining neuronal signals for extended periods of time and with multiple biological mechanisms negatively affecting electrode performance. Acute and chronic inflammation, oxidative stress, and blood brain barrier disruption contribute to inconsistent electrode performance. We hypothesized that therapeutic hypothermia (TH) applied at the microelectrode insertion site will positively modulate both inflammatory and apoptotic pathways, promoting neuroprotection and improved performance in the long-term. APPROACH A custom device and thermoelectric system were designed to deliver controlled TH locally to the cortical implant site at the time of microelectrode array insertion and immediately following surgery. The TH paradigm was derived from in vivo cortical temperature measurements and finite element modeling of temperature distribution profiles in the cortex. Male Sprague-Dawley rats were implanted with non-functional Utah microelectrodes arrays (UMEA) consisting of 4 × 4 grid of 1.5 mm long parylene-coated silicon shanks. In one group, TH was applied to the implant site for two hours following the UMEA implantation, while the other group was implanted under normothermic conditions without treatment. At 48 h, 72 h, 7 d and 14 d post-implantation, mRNA expression levels for genes associated with inflammation and apoptosis were compared between normothermic and hypothermia-treated groups. MAIN RESULTS The custom system delivered controlled TH to the cortical implant site and the numerical models confirmed that the temperature decrease was confined locally. Furthermore, a one-time application of TH post UMEA insertion significantly reduced the acute inflammatory response with a reduction in the expression of inflammatory regulating cytokines and chemokines. SIGNIFICANCE This work provides evidence that acutely applied hypothermia is effective in significantly reducing acute inflammation post intracortical electrode implantation.
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Affiliation(s)
- Elizabeth A Dugan
- Department of Biomedical Engineering, University of Miami, FL, United States of America
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Somdaş MA, Güntürk İ, Balcıoğlu E, Avcı D, Yazıcı C, Özdamar S. Protective effect of N-acetylcysteine against cisplatin ototoxicity in rats: a study with hearing tests and scanning electron microscopy. Braz J Otorhinolaryngol 2018; 86:30-37. [PMID: 30268784 PMCID: PMC9422681 DOI: 10.1016/j.bjorl.2018.08.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Revised: 07/17/2018] [Accepted: 08/14/2018] [Indexed: 10/28/2022] Open
Abstract
INTRODUCTION Ototoxicity is a health problem appearing after powerful treatments in serious health conditions. It is sometimes inevitable when treatment of the serious disease is required. Cisplatin is an antineoplastic agent which was investigated previously to reveal increased nitrogen and reactive oxygen radicals that damages hair cells, resulting in ototoxicity. N-acetylcysteine, previously shown to decrease ototoxicity caused by different agents, is known to be a powerful in vitro antioxidant. Probably N-acetylcysteine, in addition to its antioxidant effect, blocks a cascade where reactive oxygen species result in apoptosis in the cochlea. OBJECTIVES The possible preventive effect of N-acetylcysteine in cisplatin ototoxicity was studied with auditory brain stem responses, otoacoustic emissions, and histopathological investigation of the cochlea in a scanning electron microscopy. METHODS This study was conducted on 21 Wistar Albino rats in four groups. 1mL/kg/day three times in total intraperitoneal (i.p.) Saline (n=5), 500mg/kg/day i.p. three times in total N-acetylcysteine (n=5), i.p. 15mg/kg cisplatin alone (single dose) (n=5) and i.p. 15mg/kg cisplatin plus 500mg/kg/day N-acetylcysteine (n=6) were administered. The rats were anesthetized to study the hearing tests before and after the experiment. The rats were sacrificed to investigate the cochleas by scanning electron microscopy. RESULTS Auditory brain stem responses and otoacoustic emissions values were attenuated in the cisplatin group. The group that received N-acetylcysteine in addition to cisplatin had better auditory brain stem responses thresholds and otoacoustic emissions. The samples obtained from the cisplatin group showed surface irregularities, degeneration areas, and total or partial severe stereocilia losses. The changes were milder in the cisplatin+N-acetylcysteine group. CONCLUSION Cisplatin ototoxicity can be detected by auditory brain stem responses and otoacoustic emissions testing in rats. N-acetylcysteine may protect the cochlear cells from histopathological changes. We concluded that N-acetylcysteine given 4h after cisplatin injection has a potential otoprotective effect against cisplatin ototoxicity. which suggests it could be used in clinical trials.
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Affiliation(s)
- Mehmet Akif Somdaş
- Erciyes University, Faculty of Medicine, Department of Otorhinolaryngology, Kayseri, Turkey.
| | - İnayet Güntürk
- Erciyes University, School of Medicine, Department of Medical Biochemistry, Kayseri, Turkey
| | - Esra Balcıoğlu
- Erciyes University, School of Medicine, Department of Histology and Embryology, Kayseri, Turkey
| | - Deniz Avcı
- Patnos State Hospital, Department of Otorhinolaryngology, Ağrı, Turkey
| | - Cevat Yazıcı
- Erciyes University, School of Medicine, Department of Medical Biochemistry, Kayseri, Turkey
| | - Saim Özdamar
- Erciyes University, School of Medicine, Department of Histology and Embryology, Kayseri, Turkey
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Sheth S, Mukherjea D, Rybak LP, Ramkumar V. Mechanisms of Cisplatin-Induced Ototoxicity and Otoprotection. Front Cell Neurosci 2017; 11:338. [PMID: 29163050 PMCID: PMC5663723 DOI: 10.3389/fncel.2017.00338] [Citation(s) in RCA: 221] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 10/12/2017] [Indexed: 12/20/2022] Open
Abstract
Evidence of significant hearing loss during the early days of use of cisplatin as a chemotherapeutic agent in cancer patients has stimulated research into the causes and treatment of this side effect. It has generally been accepted that hearing loss is produced by excessive generation of reactive oxygen species (ROS) in cell of the cochlea, which led to the development of various antioxidants as otoprotective agents. Later studies show that ROS could stimulate cochlear inflammation, suggesting the use of anti-inflammatory agents for treatment of hearing loss. In this respect, G-protein coupled receptors, such as adenosine A1 receptor and cannabinoid 2 receptors, have shown efficacy in the treatment of hearing loss in experimental animals by increasing ROS scavenging, suppressing ROS generation, or by decreasing inflammation. Inflammation could be triggered by activation of transient receptor potential vanilloid 1 (TRPV1) channels in the cochlea and possibly other TRP channels. Targeting TRPV1 for knockdown has also been shown to be a useful strategy for ensuring otoprotection. Cisplatin entry into cochlear hair cells is mediated by various transporters, inhibitors of which have been shown to be effective for treating hearing loss. Finally, cisplatin-induced DNA damage and activation of the apoptotic process could be targeted for cisplatin-induced hearing loss. This review focuses on recent development in our understanding of the mechanisms underlying cisplatin-induced hearing loss and provides examples of how drug therapies have been formulated based on these mechanisms.
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Affiliation(s)
- Sandeep Sheth
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Debashree Mukherjea
- Department of Surgery (Otolaryngology), Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Leonard P Rybak
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, United States.,Department of Surgery (Otolaryngology), Southern Illinois University School of Medicine, Springfield, IL, United States
| | - Vickram Ramkumar
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, United States
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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] [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.
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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.
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Liu Y, Yu Y, Chu H, Bing D, Wang S, Zhou L, Chen J, Chen Q, Pan C, Sun Y, Cui Y. 17-DMAG induces Hsp70 and protects the auditory hair cells from kanamycin ototoxicity in vitro. Neurosci Lett 2014; 588:72-7. [PMID: 25556684 DOI: 10.1016/j.neulet.2014.12.060] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 12/28/2014] [Accepted: 12/30/2014] [Indexed: 01/17/2023]
Abstract
Heat shock protein 70 (Hsp70) has been known to be able to play a protective role in the cochlea. The aim of this study was to investigate whether geldanamycin hydrosoluble derivative 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG) has the ability to induce Hsp70 up-regulation to protect hair cells from kanamycin-induced ototoxicity in vitro. The organ of Corti (OC) explants were isolated from mice at postnatal day 3-5. Then, the explants were exposed to kanamycin with or without pre-incubation with 17-DMAG. The expression of Hsp70 was assessed by reverse transcription-quantitative polymerase chain reaction, ELISA, and immunofluorescent staining. The surviving hair cells were examined by phalloidin labeling and were counted. We found that Hsp70 expression in the explants after pre-incubation with 17-DMAG was significantly increased at both mRNA and protein levels. Immunofluorescent staining showed that Hsp70 was mainly located in the auditory hair cells. Compared with kanamycin group, the loss of hair cells was inhibited significantly in 17-DMAG+kanamycin group. Our study demonstrated that 17-DMAG induces Hsp70 in the hair cells, and has a significant protective effect against kanamycin ototoxicity in vitro. 17-DMAG has the possibility to be a safe and effective anti-ototoxic drug.
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Affiliation(s)
- Yun Liu
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, PR China
| | - Yang Yu
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, PR China.
| | - Hanqi Chu
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, PR China
| | - Dan Bing
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, PR China
| | - Shaoli Wang
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, PR China
| | - Liangqiang Zhou
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, PR China
| | - Jin Chen
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, PR China
| | - Qingguo Chen
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, PR China
| | - Chunchen Pan
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, PR China
| | - Yanbo Sun
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, PR China
| | - Yonghua Cui
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, PR China
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Gong TW, Fairfield DA, Fullarton L, Dolan DF, Altschuler RA, Kohrman DC, Lomax MI. Induction of heat shock proteins by hyperthermia and noise overstimulation in hsf1 -/- mice. J Assoc Res Otolaryngol 2011; 13:29-37. [PMID: 21932106 DOI: 10.1007/s10162-011-0289-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 08/23/2011] [Indexed: 11/26/2022] Open
Abstract
Diverse cellular and environmental stresses can activate the heat shock response, an evolutionarily conserved mechanism to protect proteins from denaturation. Stressors activate heat shock transcription factor 1 (HSF1), which binds to heat shock elements in the genes for heat shock proteins, leading to rapid induction of these important molecular chaperones. Both heat and noise stress are known to activate the heat shock response in the cochlea and protect it from subsequent noise trauma. However, the contribution of HSF1 to induction of heat shock proteins following noise trauma has not been investigated at the molecular level. We evaluated the role of HSF1 in the cochlea following noise stress by examining induction of heat shock proteins in Hsf1 ( +/- ) control and Hsf1 ( -/- ) mice. Heat stress rapidly induced expression of Hsp25, Hsp47, Hsp70.1, Hsp70.3, Hsp84, Hsp86, and Hsp110 in the cochleae of wild-type and Hsf1 ( +/- ) mice, but not in Hsf1 ( -/- ) mice, confirming the essential role of HSF1 in mediating the heat shock response. Exposure to broadband noise (2-20 kHz) at 106 dB SPL for 2 h produced partial hearing loss. Maximal induction of heat shock proteins occurred 4 h after the noise. In comparison to heat stress, noise stress resulted in lower induced levels of Hsp25, Hsp70.1, Hsp70.3, Hsp86, and Hsp110 in Hsf1 ( +/- ) mice. Induction of these heat shock proteins was attenuated, but not completely eliminated, in Hsf1 ( -/- ) mice. These same noise exposure conditions induced genes for several immediate early transcription factors and maximum induction occurred earlier than for heat shock proteins. Thus, additional signaling pathways and transcriptional regulators that are activated by noise probably contribute to induction of heat shock proteins in the cochlea.
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Affiliation(s)
- Tzy-Wen Gong
- Department of Otolaryngology/Head Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI 48109-5648, USA
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Geranylgeranylacetone suppresses noise-induced expression of proinflammatory cytokines in the cochlea. Auris Nasus Larynx 2011; 39:270-4. [PMID: 21794995 DOI: 10.1016/j.anl.2011.06.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 06/22/2011] [Accepted: 06/23/2011] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Heat shock transcription factor 1 (HSF1) is a master regulator of heat shock response, and also inhibits expression of inflammatory cytokines directly or indirectly. Here, we examined effects of HSF1 activation on the expression of proinflammatory cytokines in mouse cochlea after exposure to noise. METHODS Male CBA/N mice with normal Preyer's reflex were exposed to intense noise for 3h. Three hours after noise exposure, bilateral cochleae were removed and expression of major inflammatory cytokines was examined. RESULTS We found that interleukin-6 (IL-6) and interleukin-1β (IL-1β) expression increased significantly after noise exposure, and the expression was suppressed significantly in mice administered with geranylgeranylacetone (GGA), which activates HSF1. Seven days after noise exposure, thresholds for auditory brainstem response were elevated, and GGA administration significantly suppressed this elevation. CONCLUSION These results suggest that HSF1-mediated suppression of proinflammatory cytokines in the cochlea by GGA administration could be an important means of inner ear protection.
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Mazurek B, Yu Y, Haupt H, Szczepek AJ, Olze H. Salicylate modulates Hsp70 expression in the explanted organ of Corti. Neurosci Lett 2011; 501:67-71. [PMID: 21782002 DOI: 10.1016/j.neulet.2011.05.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 04/20/2011] [Accepted: 05/03/2011] [Indexed: 11/16/2022]
Abstract
Heat shock protein 70 (Hsp70, Hspa1a) is known to play a protective role in the inner ear and in the nervous system. Our recent study demonstrated that the induction of Hsp70 by geldanamycin protected the auditory hair cells against ototoxic insult. Here, using the explanted organ of Corti (OC), we characterized the effect of sodium salicylate on the expression of Hsp70. Using the real-time RT-PCR; after 27 h in standard culture, we observed an increase in the Hsp70 transcript number. After 48 h in culture, the number of Hsp70 transcripts increased further, as compared to the freshly isolated tissues or explant cultured for 27 h. Three hours after the addition of 2.5mM sodium salicylate, the expression of Hsp70 mRNA increased significantly. Interestingly, Hsp70 protein level remained unaffected by the addition of salicylate, as shown by immunoblotting and Hsp70-ELISA. Confocal microscopy imaging demonstrated predominant localization of Hsp70 protein with or without salicylate exposure to the fibrocytes of spiral limbus. Our results suggest that in the OC, explanting process induces expression of Hsp70 in limbal fibrocytes and that this expression can be enhanced by salicylate but only on mRNA and not on the protein level.
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Affiliation(s)
- Birgit Mazurek
- Molecular Biology Research Laboratory, Department of Otorhinolaryngology, Charité - Universitätsmedizin Berlin, Campus Charité Mitte, Berlin, Germany.
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García-Berrocal JR, Nevado J, González-García JA, Sánchez-Rodríguez C, Sanz R, Trinidad A, España P, Citores MJ, Ramírez-Camacho R. Heat shock protein 70 and cellular disturbances in cochlear cisplatin ototoxicity model. J Laryngol Otol 2010; 124:599-609. [PMID: 20307356 DOI: 10.1017/s0022215110000496] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Exposure to cisplatin leads to cochlear cell death by apoptosis; these changes are most marked on the seventh day after exposure. Heat shock proteins are induced in inner ear cells in response to a variety of stimuli. This study examined the role of heat shock protein 70 in cisplatin-induced cochlear cell death. METHODS Fifty-six Sprague-Dawley rats were involved. Some were injected with cisplatin (5 mg/kg body weight), some with cisplatin plus the caspase inhibitor Z-Asp(OMe)-Glu(OMe)-Val-Asp(OME)-fluoromethylketone (5 mg/kg body weight) and others were left as controls (being injected only with saline). Seven days later, we examined the expression of heat shock protein 70 and several other apoptosis-related proteins within the rat cochlear cells; we also assessed total superoxide dismutase activity, auditory brainstem response and auditory steady state response. RESULTS Seven days after cisplatin injection, significantly increased expression of heat shock protein 70 was found within the rat cochleae. This correlated with increased executioner caspase levels, total superoxide dismutase activity and auditory brainstem response thresholds, and a significant elevation in auditory steady state response thresholds. Inhibition of caspase-3 activity significantly reduced cochlear heat shock protein 70 expression and total superoxide dismutase activity, and improved auditory brainstem response and auditory steady state response thresholds. CONCLUSIONS Seven days after cisplatin exposure, we found disturbances of the cochlear cellular machinery involving heat shock protein 70, other apoptotic proteins and total superoxide dismutase.
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Yu Y, Szczepek AJ, Haupt H, Mazurek B. Geldanamycin induces production of heat shock protein 70 and partially attenuates ototoxicity caused by gentamicin in the organ of Corti explants. J Biomed Sci 2009; 16:79. [PMID: 19723345 PMCID: PMC2746196 DOI: 10.1186/1423-0127-16-79] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Accepted: 09/02/2009] [Indexed: 01/26/2023] Open
Abstract
Background Heat shock protein 70 (HSP70) protects inner ear cells from damage and death induced by e.g. heat or toxins. Benzoquinone ansamycin antibiotic geldanamycin (GA) was demonstrated to induce the expression of HSP70 in various animal cell types. The aim of our study was to investigate whether GA induces HSP70 in the organ of Corti (OC), which contains the auditory sensory cells, and whether GA can protect these cells from toxicity caused by a common aminoglycoside antibiotic gentamicin. Methods To address these questions, we used the OC explants isolated from p3-p5 rats. As a read-out, we used RT-PCR, ELISA and immunofluorescence. Results We found that GA at the concentration of 2 μM efficiently induced HSP70 expression on mRNA and protein level in the OC explants. Confocal microscopy revealed that HSP70 induced by GA is expressed by hair cells and interdental cells of spiral limbus. Preincubation of explants with 2 μM GA prior to adding gentamicin (500 μM) significantly reduced the loss of outer but not inner hair cells, suggesting different mechanisms of otoprotection needed for these two cell types. Conclusion GA induced HSP70 in the auditory sensory cells and partially protected them from toxicity of gentamicin. Understanding the molecular mechanisms of GA otoprotection may provide insights for preventative therapy of the hearing loss caused by aminoglycoside antibiotics.
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Affiliation(s)
- Yang Yu
- Molecular Biology Research Laboratory and Tinnitus Center, Department of Otorhinolaryngology, Charité-Universitätsmedizin Berlin, Campus Charité Mitte, Charitéplatz 1, 10117 Berlin, Germany.
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de Freitas MR, da Silva VC, de Castro Brito GA, de Carvalho JV, Gomes RM, de Albuquerque Ribeiro R. Distortion-product otoacoustic emissions and auditory brainstem responses sensitivity assessment in cisplatin-induced ototoxicity in rats. Braz J Otorhinolaryngol 2009. [PMID: 19784413 PMCID: PMC9446066 DOI: 10.1016/s1808-8694(15)30483-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Cisplatin (cis-diamminedicloroplatinum) is an antineoplastic drug used in the treatment of a variety of cancers, especially head-and-neck cancer. Its ototoxicity, however, has been noted as a common side-effect which limits its use and causes significant morbidity. Aim to assess distortion-product otoacoustic emissions (DPOAE) and brainstem evoked response audiometry (BERA) sensitivity to detect secondary ototoxicity caused by different doses and means of administration of cisplatin in rats. Study Design Experimental. Materials and Methods Male Wistar rats were intraperitoneally (i.p.) injected with 24 mg/kg cisplatin, divided into three equal doses (8mg/kg) or a single i.p. injection of 16 mg/kg. The animals were evaluated by distortion product otoacoustic emission (DPOAE) or brainstem evoked response audiometry (BERA) on the 3rd and 4th days after the cisplatin injection. Results Treatment with cisplatin 24 mg/kg resulted in significant DPOAE decrease and it raised the BERA electrophysiological threshold. The 16mg/kg dose could not significantly reduce the DPOAE amplitude, but it raised the animals' hearing thresholds – detected by the BERA. Conclusion In rats, BERA was more sensitivity than DPOAE at detecting cisplatin-induced ototoxicity in rats considering different doses and means of administration.
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Yamashita H. [Treatment of labyrinthine diseases--the frontier of pre-clinical studies. Therapeutic strategy to protect the peripheral vestibular organ]. NIHON JIBIINKOKA GAKKAI KAIHO 2009; 112:12-17. [PMID: 19288620 DOI: 10.3950/jibiinkoka.112.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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15
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Attenuation of progressive hearing loss in a model of age-related hearing loss by a heat shock protein inducer, geranylgeranylacetone. Brain Res 2008; 1212:9-17. [PMID: 18445491 DOI: 10.1016/j.brainres.2008.03.031] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2007] [Revised: 03/06/2008] [Accepted: 03/12/2008] [Indexed: 11/20/2022]
Abstract
Mechanisms of age-related hearing loss (ARHL) have not been elucidated as aging processes are extremely complex. Although oxidative stress and apoptotic cell death are involved in progression of ARHL, number of trial to treat ARHL is limited. Heat shock response is characterized by induction of heat shock proteins (HSPs) in response to stresses such as heat shock, which diminishes during aging. HSPs act as molecular chaperones, and some HSPs also inhibit apoptotic pathways. Here, we examined age-related expression of HSPs in the cochlea of ARHL model DBA/2J mice and control CBA/N mice. Western blot assay revealed that CBA/N mice showed constant expression of Hsp70 and Hsp110 with age, but not in DBA/2J mice. The result suggests that pharmacological upregulation of HSPs might attenuate ARHL. We administered DBA/2J mice with food containing geranylgeranylacetone (GGA) that induces HSPs in the cochlea, and found that its administration suppresses ARHL examined by ABR test and histological examination though protection is specific for the apical part of the cochlea. These results demonstrate that dietary supplementation of GGA could be an effective therapeutic strategy for treatment of ARHL.
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Ramírez-Camacho R, Citores MJ, Trinidad A, Verdaguer JM, García-Berrocal JR, Marero AM, Puente A, González-García JA, Vargas JA. HSP-70 as a nonspecific early marker in cisplatin ototoxicity. Acta Otolaryngol 2007; 127:564-7. [PMID: 17503223 DOI: 10.1080/00016480600951483] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
CONCLUSION The great variety of pathological entities related to the presence of circulating HSP-70 suggests a nonspecific cellular damage. As the present study shows, positive results decrease with respect to the time elapsed after the injection of the ototoxic agent. HSP-70 appears as an early and transient marker that could permit early detection of inner ear damage. OBJECTIVES The aim of this study was to determine the presence of HSP-70 at different time points by means of Western blot immunoassay in the sera of rats treated with cisplatin. MATERIALS AND METHODS Thirty-six Wistar rats were intraperitoneally injected with cisplatin at a dose of 5 mg/kg and blood samples were collected at 7 and 90 days. Determination of HSP-70 was made by means of a modified Western blot immunoassay kit originally used for human HSP-70 antigen detection. A control group of 18 animals was used for comparison. RESULTS Western blot was positive in 77.8% of the animals in the 7 days group, decreasing to a 44.4% in the 90 days group. In the control group, Western blot was positive in 5.5%.
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Affiliation(s)
- R Ramírez-Camacho
- Ear Research Group, Department of Otorhinolaryngology, Hospital Universitario Puerta de Hierro, USA.
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17
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Coradini PP, Cigana L, Selistre SGA, Rosito LS, Brunetto AL. Ototoxicity from cisplatin therapy in childhood cancer. J Pediatr Hematol Oncol 2007; 29:355-60. [PMID: 17551394 DOI: 10.1097/mph.0b013e318059c220] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Cisplatin has been associated with hearing damage. It is usually irreversible, bilateral, and characterized by high-frequency sensorineural hearing loss. This study was carried out to identify impairment of hearing function in children and adolescents with cancer after cisplatin therapy. Twenty-three survivors of childhood cancer treated with cisplatin at our Unit from 1991 to 2004 performed tympanometry, pure tone audiometry, transient otoacoustic emissions, and distortion product otoacoustic emissions (DPOAE). The median age at diagnosis was 12.3 years and the median total dose of cisplatin received was 406 mg/m2. Fifty-two percent of patients had bilateral and in the high frequencies range hearing loss on audiometry. Transient otoacoustic emission and DPOAE abnormalities were detected in 22% and in 71% of the patients, respectively. We found a high concordance between the findings of audiometry and DPOAE (P=0.01). There was no influence of sex and number of ototoxic drugs other than cisplatin on hearing loss. There was a trend for younger age and higher cumulative dose of cisplatin to be associated with greater severity of hearing damage. Our data provide further evidence on hearing damage due to cisplatin therapy in children. The high incidence of patients with hearing function abnormalities found in this study and in previous reports highlights the importance of monitoring hearing function in children and adolescents undergoing cisplatin therapy, or as early as possible at follow-up. This study also demonstrates that DPOAE should be used for screening of hearing abnormalities and, once hearing damage is identified, patients require expert audiologic pediatric evaluation and (where indicated) use of hearing aids and/or speech therapy.
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Affiliation(s)
- Patrícia P Coradini
- Pediatric Oncology Unit, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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Coling DE, Ding D, Young R, Lis M, Stofko E, Blumenthal KM, Salvi RJ. Proteomic analysis of cisplatin-induced cochlear damage: Methods and early changes in protein expression. Hear Res 2007; 226:140-56. [PMID: 17321087 DOI: 10.1016/j.heares.2006.12.017] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2006] [Revised: 12/06/2006] [Accepted: 12/23/2006] [Indexed: 11/30/2022]
Abstract
To identify early changes in protein expression associated with cisplatin ototoxicity, we used two dimensional-difference gel electrophoresis (2D-DIGE) and matrix-assisted laser desorption-time-of-flight (MALDI-TOF) mass spectrometry to analyze proteins from P3 rat cochleae that were cultured for 3h with or without 1mM cisplatin. Replicate analysis of fluorescent images from six gels revealed significant (p<0.01) cisplatin-induced changes (greater than 1.5-fold) in expression of 22 cochlear proteins. These include increases in the expression of five proteins, four of which were identified as nucleobindin 1, a nuclear calcium signaling and homeostasis protein (2.1-fold), heterogeneous nuclear ribonucleoprotein C, an RNA processing protein (1.8-fold), a 55 kDa protein that is either endothelial differentiation-related factor 1 or alpha-6 tubulin (1.7-fold), and calreticulin, a calcium binding chaperone of the endoplasmic reticulum (ER, 1.6-fold). The expression of 17 proteins was significantly (p<0.01) decreased by greater than 1.5-fold. These include ribonuclease/angiogenin inhibitor 1 (1.6-fold), RAS-like, family 12 (predicted), ras association (RalGDS/AF-6) domain family 5 (4.5-fold), homologous the RAS family of GTPase signaling proteins (2.4-fold), and Protein tyrosine phosphatase domain containing 1 (predicted, 6.1-fold). We identified seven cochlear proteins with either smaller (1.2-1.5-fold) or less significant (p<0.05) cisplatin-induced changes in expression. Notably, heat shock 70 kDa protein 5 (Hspa5, Grp78, and BiP), an ER chaperone protein involved in stress response, decreased 1.7-fold. We observed changes consistent with phosphorylation in the level of isoforms of another ER stress-induced protein, glucose-regulated protein Grp58. Changes in cisplatin-induced protein expression are discussed with respect to known or hypothesized functions of the identified proteins.
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Affiliation(s)
- Donald E Coling
- Center for Hearing and Deafness, 137 Cary Hall, University at Buffalo, Buffalo, NY 14214, USA.
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19
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Cunningham LL, Brandon CS. Heat shock inhibits both aminoglycoside- and cisplatin-induced sensory hair cell death. J Assoc Res Otolaryngol 2006; 7:299-307. [PMID: 16794914 PMCID: PMC2504613 DOI: 10.1007/s10162-006-0043-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2006] [Accepted: 05/11/2006] [Indexed: 12/19/2022] Open
Abstract
Human hearing and balance impairments are often attributable to the death of sensory hair cells in the inner ear. These cells are hypersensitive to death induced by noise exposure, aging, and some therapeutic drugs. Two major classes of ototoxic drugs are the aminoglycoside antibiotics and the antineoplastic agent cisplatin. Exposure to these drugs leads to hair cell death that is mediated by the activation of specific apoptotic proteins, including caspases. The induction of heat shock proteins (HSPs) in response to cellular stress is a ubiquitous and highly conserved response that can significantly inhibit apoptosis in some systems by inhibiting apoptotic proteins. Induction of HSPs occurs in hair cells in response to a variety of stimuli. Given that HSPs can directly inhibit apoptosis, we hypothesized that heat shock may inhibit apoptosis in hair cells exposed to ototoxic drugs. To test this hypothesis, we developed a method for inducing HSP expression in the adult mouse utricle in vitro. In vitro heat shock reliably produces a robust up-regulation of HSP-70 mRNA and protein, as well as more modest up-regulation of HSP-90 and HSP-27. The heat shock does not result in death of hair cells. Heat shock has a significant protective effect against both aminoglycoside- and cisplatin-induced hair cell death in the utricle preparation in vitro. These data indicate that heat shock can inhibit ototoxic drug-induced hair cell death, and that the utricle preparation can be used to examine the molecular mechanism(s) underlying this protective effect.
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Affiliation(s)
- Lisa L Cunningham
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Box 250908, Charleston, SC 29425, USA.
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20
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Sano H, Yoneda S, Iwase H, Itoh A, Hashimoto D, Okamoto M. Effect of geranylgeranylacetone on gentamycin ototoxicity in rat cochlea culture. Auris Nasus Larynx 2006; 34:1-4. [PMID: 16934423 DOI: 10.1016/j.anl.2006.05.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Revised: 05/23/2006] [Accepted: 05/26/2006] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Geranylgeranylacetone (GGA), an anti-ulcer drug, has been reported to induce heat shock proteins (HSPs) in several animal organs. Purpose of this study was to investigate whether GGA has protective effect on gentamycin (GM) ototoxicity and whether it induces HSP70 in rat cochlea. METHODS We used cochlea explant culture from postnatal 5-day rat. Explants were pre-incubated with GGA, then incubated with GM and GGA. The number of surviving outer hair cells (OHCs) labeled by phalloidin was counted to evaluate the protective effect of GGA. The expression of HSP70 in whole cochlea tissue was investigated by immunoblot analysis. RESULTS The number of surviving OHCs was significantly high in GGA 10(-5)M group compared to GM only group and GGA 10(-6)M group. In the immunoblot analysis, HSP70 levels in GGA added groups were slightly high compared to simple culture group, but much lower than those in heat shock group. CONCLUSION It was suggested that GGA-induced HSP70, and had partial protective effects on GM ototoxicity in the cochlea. GGA has possibility to be safe and useful treatment drug for cochlea disorder.
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Affiliation(s)
- Hajime Sano
- Department of Otolaryngology, Kitasato University, School of Medicine, 1-15-1 Kitasato, Sagamihra, Kanagawa 228-8555, Japan.
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21
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Park SN, Yeo SW, Park KH. Serum heat shock protein 70 and its correlation with clinical characteristics in patients with sudden sensorineural hearing loss. Laryngoscope 2006; 116:121-5. [PMID: 16481823 DOI: 10.1097/01.mlg.0000187401.75156.b2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Previous studies have reported that in cochlear cells, heat shock protein (HSP)70 is expressed after ototoxic stimuli. We performed this study to investigate the possibility of HSP70 being found in circulation and to observe its possible clinical role in patients with sudden sensorineural hearing loss (SSNHL). METHODS A total of 67 patients with SSNHL and age-sex matched normal controls were included in this study. Their serum HSP70 levels were measured with highly sensitive enzyme-linked immunoadsorbent assay (ELISA) test and confirmed with Western blot immunoassay. Clinical variables including initial and final audiometric findings and accompanying symptoms were analyzed to find the possible clinical value of serum HSP70 level in the patients with SSNHL. RESULTS Serum HSP70 levels were significantly higher in the patients with SSNHL than those of normal controls by ELISA test (P < .01), and their presence were confirmed as strong bands in the Western blot assay. There was significant correlation between serum HSP70 levels and the recovery of HL in the patients with SSNHL (P < .01). CONCLUSION This is the first report showing elevated serum HSP70 levels in the patients with SSNHL compared with normal controls. We suggest that serum HSP70 levels might have a clinical role for predicting prognosis of HL in the patients with SSNHL.
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Affiliation(s)
- Shi-Nae Park
- Department of Otolaryngology, Kangnam St. Mary's Hospital, The Catholic University of Korea, College of Medicine, Seoul, Korea
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22
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Mukherjea D, Whitworth CA, Nandish S, Dunaway GA, Rybak LP, Ramkumar V. Expression of the kidney injury molecule 1 in the rat cochlea and induction by cisplatin. Neuroscience 2006; 139:733-40. [PMID: 16464536 DOI: 10.1016/j.neuroscience.2005.12.044] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2005] [Revised: 12/16/2005] [Accepted: 12/22/2005] [Indexed: 11/29/2022]
Abstract
Cisplatin is a widely used chemotherapeutic agent whose dose-limiting side effects include ototoxicity and nephrotoxicity. Recent evidence indicates that cisplatin induces the expression of a novel protein, kidney injury molecule-1, in the renal proximal tubular epithelium to aid in regeneration. In this study, we determined whether kidney injury molecule-1 is expressed in the cochlea and is induced by cisplatin. Using reverse transcriptase polymerase chain reaction techniques, we have now identified kidney injury molecule-1 in the rat cochlea and in three different mouse transformed hair cell lines. Administration of cisplatin to rats produced hearing loss and induced kidney injury molecule-1 mRNA in the rat cochlea. Pretreatment of rats with lipoic acid, a scavenger of reactive oxygen species, significantly reduced cisplatin-induced hearing loss and kidney injury molecule-1 expression. Cisplatin also increased the expression of cochlear NOX3 mRNA, a member of the superoxide generating NADPH oxidase family of proteins recently identified in the cochlea, inhibition of which decreased kidney injury molecule-1 expression. Polymerase chain reaction performed on different regions of the cochlea indicated the presence of kidney injury molecule-1 mRNA in the lateral wall, organ of Corti and spiral ganglion. This distribution was confirmed by immunocytochemistry. Taken together, these data identify kidney injury molecule-1 as a novel cochlear injury molecule, whose expression is regulated by reactive oxygen species generated via the NADPH oxidase pathway.
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Affiliation(s)
- D Mukherjea
- Department of Pharmacology, Southern Illinois University School of Medicine, PO Box 19629, Springfield, IL 62794-9626, USA
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23
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Mikuriya T, Sugahara K, Takemoto T, Tanaka K, Takeno K, Shimogori H, Nakai A, Yamashita H. Geranylgeranylacetone, a heat shock protein inducer, prevents acoustic injury in the guinea pig. Brain Res 2005; 1065:107-14. [PMID: 16309629 DOI: 10.1016/j.brainres.2005.10.045] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2005] [Revised: 10/09/2005] [Accepted: 10/15/2005] [Indexed: 11/16/2022]
Abstract
Geranylgeranylacetone (GGA) used widely as anti-ulcer agent is accepted as an inducer of the heat shock proteins (Hsps) at gastric mucosa, liver, heart, and brain. However, there have been no reports that GGA could induce Hsps in the cochlea leading up to the oto-protection. The purpose of the present study was to investigate whether single oral dose of GGA could induce Hsps at cochlea and oral administration had protective effect to the cochlea against noise trauma. We used Hartley guinea pigs and investigated the expression of Hsp70, 40, and 27 in cochlea by Western blot analysis. To evaluate cochlear function, we assessed thresholds of the auditory brain stem response (ABR). For histological assessment, we observed the sensory epithelium using surface preparation technique. GGA (600 mg/kg) or vehicle was given orally to animals. Western blot analysis showed that the expressions of Hsp 70, 40, and 27 were increased 24-48 h after administration of single dose of GGA, whereas there was less expression in the animals given vehicle. In the animals given GGA once a day for a week before sound exposure (130 dB SPL octave band noise with a center frequency of 4 kHz) for 3 h, their ABR threshold elevations were lowered significantly. In addition, significantly fewer defects were observed on outer hair cells of organ of Corti in the animals treated by GGA than those of the animals without GGA. This result shows that pretreatment by GGA have a potential to prevent cochlea damage against the intense noise.
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MESH Headings
- Animals
- Anti-Ulcer Agents/pharmacology
- Blotting, Western
- Cochlea/drug effects
- Cochlea/metabolism
- Cochlea/pathology
- Diterpenes/pharmacology
- Evoked Potentials, Auditory, Brain Stem/drug effects
- Guinea Pigs
- Hair Cells, Auditory, Outer/drug effects
- Hair Cells, Auditory, Outer/pathology
- Hearing Loss, Noise-Induced/metabolism
- Hearing Loss, Noise-Induced/pathology
- Hearing Loss, Noise-Induced/prevention & control
- Heat-Shock Proteins/biosynthesis
- Male
- Noise/adverse effects
- Stimulation, Chemical
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Affiliation(s)
- Takefumi Mikuriya
- Department of Otolaryngology, Yamaguchi University School of Medicine, Minamikogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan
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Fairfield DA, Lomax MI, Dootz GA, Chen S, Galecki AT, Benjamin IJ, Dolan DF, Altschuler RA. Heat shock factor 1-deficient mice exhibit decreased recovery of hearing following noise overstimulation. J Neurosci Res 2005; 81:589-96. [PMID: 15952177 DOI: 10.1002/jnr.20417] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Heat shock proteins (Hsps) can enhance cell survival in response to stress. Heat shock factor 1 (Hsf1) is the major transcription factor that regulates stress-inducible Hsp expression. We previously demonstrated the presence of Hsf1 in the rodent cochlea and also demonstrated that a heat shock known to precondition the cochlea against noise trauma results in Hsf1 activation in the rodent cochlea. In the present study, we used an Hsf1-deficient (Hsf1-/- mouse model to determine whether eliminating the Hsf1-dependent stress pathway would influence hearing loss and/or recovery from a moderate-intensity noise. Hsf1-/- mice and their normal littermates (Hsf1+/+) were exposed to a 98-dB, broadband (2-20 kHz) noise for 2 hr, and auditory brainstem response thresholds were measured at three frequencies (4, 12, and 20 kHz) 3 hr, 3 days, and 2 weeks after noise. Hsf1-/- mice had greater hearing loss than Hsf1+/+ mice, with significant differences in recovery observed at all frequencies tested by 2 weeks after noise. Increased outer hair cell loss was also observed in Hsf1-/- mice following noise. These studies provide evidence for the importance of Hsf1 in cochlear protection, recovery, and/or repair following noise overstimulation.
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Affiliation(s)
- Damon A Fairfield
- Kresge Hearing Research Institute, Department of Otolaryngology/Head Neck Surgery, University of Michigan, Ann Arbor, Michigan 48109-0506, USA
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25
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Holt AG, Asako M, Lomax CA, MacDonald JW, Tong L, Lomax MI, Altschuler RA. Deafness-related plasticity in the inferior colliculus: gene expression profiling following removal of peripheral activity. J Neurochem 2005; 93:1069-86. [PMID: 15934929 DOI: 10.1111/j.1471-4159.2005.03090.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The inferior colliculus (IC) is a major center of integration in the ascending as well as descending auditory pathways, where both excitatory and inhibitory amino acid neurotransmitters play a key role. When normal input to the auditory system is decreased, the balance between excitation and inhibition in the IC is disturbed. We examined global changes in gene expression in the rat IC 3 and 21 days following bilateral deafening, using Affymetrix GeneChip arrays and focused our analysis on changes in expression of neurotransmission-related genes. Over 1400 probe sets in the Affymetrix Rat Genome U34A Array were identified as genes that were differentially expressed. These genes encoded proteins previously reported to change as a consequence of deafness, such as calbindin, as well as proteins not previously reported to be modulated by deafness, such as clathrin. A subset of 19 differentially expressed genes was further examined using quantitative RT-PCR at 3, 21 and 90 days following deafness. These included several GABA, glycine, glutamate receptor and neuropeptide-related genes. Expression of genes for GABA-A receptor subunits beta2, beta3, and gamma2, plus ionotropic glutamate receptor subunits AMPA 2, AMPA 3, and kainate 2, increased at all three times. Expression of glycine receptor alpha1 initially declined and then later increased, while alpha2 increased sharply at 21 days. Glycine receptor alpha3 increased between 3 and 21 days, but decreased at 90 days. Of the neuropeptide-related genes tested with qRT-PCR, tyrosine hydroxylase decreased approximately 50% at all times tested. Serotonin receptor 2C increased at 3, 21, and 90 days. The 5B serotonin receptor decreased at 3 and 21 days and returned to normal by 90 days. Of the genes tested with qRT-PCR, only glycine receptor alpha2 and serotonin receptor 5B returned to normal levels of expression at 90 days. Changes in GABA receptor beta3, GABA receptor gamma2, glutamate receptor 2/3, enkephalin, and tyrosine hydroxylase were further confirmed using immunocytochemistry.
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Affiliation(s)
- Avril Genene Holt
- Kresge Hearing Research Institute, Department of Otolaryngology/Head Neck Surgery, University of Michigan, Ann Arbor, Michigan, USA.
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Sone M, Hayashi H, Yamamoto H, Hoshino T, Mizushima T, Nakashima T. Upregulation of HSP by geranylgeranylacetone protects the cochlear lateral wall from endotoxin-induced inflammation. Hear Res 2005; 204:140-6. [PMID: 15925199 DOI: 10.1016/j.heares.2005.01.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2004] [Accepted: 01/22/2005] [Indexed: 01/23/2023]
Abstract
We investigated whether an acyclic polyisoprenoid antiulcer drug, geranylgeranylacetone (GGA), induces the expression of HSP70 in the rat cochlea. Immunoblotting revealed upregulation of HSP70 in the cochlea at 12 h after transtympanic (local) or oral (systemic) administration of GGA, and this increased at 24 h after administration. Positive immunohistochemical staining of HSP70 was observed in the hair cells, the spiral ganglion, the stria vascularis, the spiral ligament, and the perivascular portion of modiolar vessels. We therefore subsequently studied the effects of GGA as an HSP-inducer on inner ear trauma due to inflammation. Damage to the lateral wall due to inflammation induced by lipopolysaccharide inoculation was protected against by pretreatment with GGA, as assessed physiologically by measurement of cochlear blood flow and morphologically by electron microscopy. The results of the present study suggest that GGA can protect the cochlea against other injuries including those induced by noise, ototoxic drugs, and ischemia by upregulating HSP70.
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Affiliation(s)
- Michihiko Sone
- Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan.
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27
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Ramírez-Camacho R, García-Berrocal JR, Buján J, Martín-Marero A, Trinidad A. Supporting cells as a target of cisplatin-induced inner ear damage: therapeutic implications. Laryngoscope 2004; 114:533-7. [PMID: 15091230 DOI: 10.1097/00005537-200403000-00027] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES/HYPOTHESIS Cisplatin induces adverse effects such as ototoxicity and nephrotoxicity. Unexplained hearing improvement in sudden deafness and fluctuating hearing loss suggests the presence of some mechanisms other than the primary lesion of the outer hair cell. The authors' aim was to study the functional and morphological lesions induced in the cochlea of the rat after cisplatin injection. STUDY DESIGN Prospective experimental morphological and functional study. METHODS Forty-eight Wistar rats were given intraperitoneal injections of 5 mg/kg cisplatin. After short-, medium-, and long-term survival, animals were studied by means of auditory brainstem response testing and scanning electronic microscopy. RESULTS An increased hearing loss was observed in animals with long-term survival compared with animals with short-term survival after a single dose of cisplatin. These findings correlated with a more intense injury of the supporting cells, continuing with the late deterioration of the hair cells. CONCLUSION The study suggested that the initial damage of the supporting cells could be responsible for the late injury of the hair cells. This hypothesis was supported by the late increase in hearing loss after a single dose of cisplatin, emphasizing the role of the supporting cells in the cochlear changes induced by cisplatin.
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Affiliation(s)
- Rafael Ramírez-Camacho
- Department of Otolaryngology, Clínica Puerta de Hierro, Autónoma University, Madrid, Spain.
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28
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Fairfield DA, Kanicki AC, Lomax MI, Altschuler RA. Induction of heat shock protein 32 (Hsp32) in the rat cochlea following hyperthermia. Hear Res 2004; 188:1-11. [PMID: 14759565 DOI: 10.1016/s0378-5955(03)00369-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2003] [Revised: 11/04/2003] [Accepted: 11/04/2003] [Indexed: 01/03/2023]
Abstract
The genes for heat shock proteins (Hsps) can be upregulated in response to cellular trauma, resulting in enhanced cell survival and protection. Hsp32, also known as heme oxygenase 1, catalyzes the degradation of heme to produce carbon monoxide and bilirubin, which play a variety of cytoprotective functions at physiological concentrations, and iron, which is rapidly sequestered by the iron-binding protein ferritin. In the present study we examined the expression and localization of Hsp32 in the rat cochlea after heat shock using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), Western blot, and immunocytochemistry. Low levels of constitutive Hsp32 expression were observed in the normal rat cochlea by RT-PCR and Western blot. Hsp32 mRNA (messenger RNA) was present at higher levels in a subfraction containing sensorineural epithelium and lateral wall than in a subfraction containing modiolus. Western blot revealed that Hsp32 protein levels increase in the rat cochlea following heat shock. Immunocytochemistry showed scattered staining of outer hair cells in the organ of Corti of normal untreated rats. Following heat shock Hsp32 is upregulated in outer hair cells and the cells of the stria vascularis. These results suggest a potential role for Hsp32 as a component of the oxidative stress response pathway in the rat cochlea.
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Affiliation(s)
- Damon A Fairfield
- Kresge Hearing Research Institute, Department of Otolaryngology/Head Neck Surgery, University of Michigan, 1301 East Ann Street, Ann Arbor, MI 48109-0506, USA
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29
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Paz Z, Freeman S, Horowitz M, Sohmer H. Prior Heat Acclimation Confers Protection against Noise-Induced Hearing Loss. Audiol Neurootol 2004; 9:363-9. [PMID: 15475665 DOI: 10.1159/000081409] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2003] [Accepted: 12/10/2003] [Indexed: 11/19/2022] Open
Abstract
Exposure to intense noise stress can cause a permanent noise-induced hearing loss which is thought to be due to elevation of reactive oxygen species in excess of the inherent antioxidant mechanisms of the cell. However, preconditioning to low levels of stress of one type can activate cellular mechanisms leading to the elevation of antioxidant levels so that the cell is then better able to tolerate subsequent severe stress of a different type. This has been called cross-tolerance. Here, we tested this hypothesis by acclimating rats to a moderate heat stress (30 days at 34 degrees C). The rats were exposed to 113 dB SPL noise for 3 days (12 h/day) in three different groups: heat acclimated then noise exposed; noise exposed and then heat acclimated; heat acclimated, then noise exposed and then heat acclimated again. Permanent changes in auditory function--auditory nerve brainstem evoked responses (ABR) and distortion product otoacoustic emissions (DPOAEs)--were evaluated in each of these animals and compared with those in rats exposed to noise only and in control groups of rats. Statistical evaluation of the results showed that when assessed with ABR, each of the heat-acclimated, noise-exposed groups was protected from the noise, even the group that was heat-acclimated after the noise exposure. When assessed with DPOAE, protection was statistically apparent only in the group that was heat acclimated, then exposed to noise, and not in the other groups. Thus, heat acclimation provides protection against permanent noise-induced hearing loss.
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Affiliation(s)
- Ziv Paz
- Department of Physiology, Hebrew University-Hadassah Medical School, Jerusalem, Israel
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Sugahara K, Inouye S, Izu H, Katoh Y, Katsuki K, Takemoto T, Shimogori H, Yamashita H, Nakai A. Heat shock transcription factor HSF1 is required for survival of sensory hair cells against acoustic overexposure. Hear Res 2003; 182:88-96. [PMID: 12948605 DOI: 10.1016/s0378-5955(03)00180-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
To analyze the role of heat shock response in the cochleae, we induced major heat shock proteins, Hsp70, Hsp90, and Hsp27 by perfusion of hot saline into the middle ear cavity (called 'local heat shock') in guinea pigs. Hsps were induced in almost all of the cochlear cells including the sensory hair cells in the organ of Corti. We showed that loss of both the sensory hair cells and the auditory function induced by acoustic overexposure was inhibited by pretreatment of the inner ear with local heat shock. To examine the role of heat shock transcription factor 1(HSF), which activates heat shock genes in response to heat shock, in the protection of sensory hair cells, we analyzed acoustic injury in HSF1-null mice. We found that the loss of sensory hair cells was more significant in HSF1-null mice compared with that of wild-type mice when mice were subjected to acoustic overexposure. These results indicate that HSF1 is required for survival of the sensory hair cells against acoustic overexposure.
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Affiliation(s)
- Kazuma Sugahara
- Department of Biochemistry and Molecular Biology, Yamaguchi University School of Medicine, Minami-Kogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan
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Kawamoto K, Yagi M, Stöver T, Kanzaki S, Raphael Y. Hearing and hair cells are protected by adenoviral gene therapy with TGF-beta1 and GDNF. Mol Ther 2003; 7:484-92. [PMID: 12727111 DOI: 10.1016/s1525-0016(03)00058-3] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF) overexpression in the inner ear can protect hair cells against degeneration induced by aminoglycoside ototoxicity. The protective efficiency of GDNF increases when it is combined with co-factors such as transforming growth factor beta1 (TGF-beta1), a ubiquitous cytokine. The aim of this study was to determine whether TGF-beta1 receptors are expressed in the inner ear and whether a cocktail of GDNF and TGF-beta1 transgenes provides enhanced protection of the inner ear against ototoxic trauma. Using RT-PCR analysis, we determined that both TGF-beta1 receptors, type 1 and 2 are present in rat cochlea. We co-inoculated two adenoviral vectors, one encoding human TGF-beta1 gene (Ad.TGF-beta1) and the other encoding human GDNF gene (Ad.GDNF) into guinea pig cochleae 4 days prior to injecting an ototoxic dose of aminoglycosides. Inoculated ears had better hearing and fewer missing inner hair cells after exposure to the aminoglycoside ototoxicity, as compared with controls and ears treated only with Ad.GDNF. Cochleae with TGF-beta1 overexpression exhibited fibrosis in the scala tympani regardless of the presence of GDNF. Our results suggest that the adenovirus-mediated overexpression of GDNF and TGF-beta1 can be used in combination to protect cochlear hair cells and hearing from ototoxic trauma.
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Affiliation(s)
- Kohei Kawamoto
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, The University of Michigan, Ann Arbor, Michigan 48109-0648, USA.
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Fairfield DA, Kanicki AC, Lomax MI, Altschuler RA. Expression and localization of heat shock factor (Hsf) 1 in the rodent cochlea. Hear Res 2002; 173:109-18. [PMID: 12372640 DOI: 10.1016/s0378-5955(02)00607-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Activation of heat shock factors (Hsfs) is one of the potential mechanisms for regulating the transcription of the heat shock proteins (Hsps) and certain other stress-responsive genes. Reverse transcription polymerase chain reaction (RT-PCR), Western blot and immunocytochemistry were used to examine the expression and localization of Hsf1, the stress-responsive member of the Hsf family, in the rat and mouse cochlea. Cerebellum was used as a positive control. Semi-quantitative RT-PCR of cochlear RNA revealed that Hsf1 was more highly expressed in a subfraction containing sensorineural epithelium and lateral wall than in a subfraction containing modiolus, with the alpha splice form predominant over the beta in both subfractions. Immunocytochemistry showed selective staining in the rodent cochlea. Hsf1 immunostaining was found in the nuclei of inner and outer hair cells in the organ of Corti, spiral ganglion cells in the modiolus, and cells in the marginal and intermediate layers of the stria vascularis. This is largely consistent with where Hsp70 induction is reported. Hsf1 activation following heat shock was examined by Western blot. Hyperthermia resulted in stress-induced Hsf1 hyperphosphorylation in cochlea as well as cerebellum. This hyperphosphorylation as well as the correlation of its localization with Hsp70 induction supports a role for Hsf1 in the cochlear stress response.
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Affiliation(s)
- Damon A Fairfield
- Kresge Hearing Research Institute, Department of Otolaryngology/Head Neck Surgery, The University of Michigan, 1301 East Ann Street, Ann Arbor 48109-0506, USA
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Ramírez Camacho R, García Berrocal JR, Trinidad A, Martín Marero A, Buján J. [Cochlear cytotoxic activity of cisplatin in experimentation animals. A study using scanning electron microscopy]. ACTA OTORRINOLARINGOLOGICA ESPANOLA 2002; 53:538-42. [PMID: 12530194 DOI: 10.1016/s0001-6519(02)78347-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cisplatin is an antitumoral agent commonly used in the treatment of different solid tumors. Its use induces adverse effects like oto- and nephrotoxicity due to acute renal failure. This makes it a suitable drug when creating an experimental model of ototoxicity. Our aim is to study the cellular lesions induced in the cochlea of the rat and the guinea pig by variable doses of cisplatin injected intraperitoneally, after short, middle, and long term survival, by means of scanning electronic microscopy. Results show the global effect of the cells of the organ of Corti with a more intense initial damage of the supporting cells, continuing with the late effect of the sensorial cells.
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Affiliation(s)
- R Ramírez Camacho
- Servicio de Otorrinolaringología, Clínica Puerta de Hierro, UAM, Madrid.
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Duan ML, Ulfendahl M, Laurell G, Counter SA, Counter AS, Pyykkö I, Borg E, Rosenhall U. Protection and treatment of sensorineural hearing disorders caused by exogenous factors: experimental findings and potential clinical application. Hear Res 2002; 169:169-78. [PMID: 12121749 DOI: 10.1016/s0378-5955(02)00484-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
During the last decade, there have been numerous interesting findings regarding the roles of neurotrophins, nitric oxide, reactive oxygen species, glutamate receptors, and shock protein in the auditory system. These findings have provided a scientific basis for the development of techniques to protect the auditory system against trauma as well as for the treatment of peripheral hearing disorders. This review focuses on recent advances in experimental prevention and treatment of hearing impairment which are expected to be of clinical value in the near future. Viral vector and non-viral vector gene therapy and transplantation of stem cells are discussed as potential treatments of irreversible sensorineural inner ear damage.
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Affiliation(s)
- Mao Li Duan
- Institute for Hearing and Communication Research, Karolinska Institutet, Karolinska Hospital, S-171 76, Stockholm, Sweden.
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García Berrocal JR, Ramírez-Camacho R, Arellano B, Vargas JA. Validity of the Western blot immunoassay for heat shock protein-70 in associated and isolated immunorelated inner ear disease. Laryngoscope 2002; 112:304-9. [PMID: 11889388 DOI: 10.1097/00005537-200202000-00019] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To assess the validity of the Western blot immunoassay for heat shock protein-70 (hsp-70) for diagnosis of autoimmune inner ear disease. STUDY DESIGN Retrospective study of 53 patients affected by sudden deafness (n = 19), idiopathic progressive sensorineural hearing loss (n = 24), and Meniere's disease (n = 10) who were treated from 1995 to 1999. The clinical course and response to corticosteroid were evaluated. METHODS A purified hsp-70 antigen from bovine kidney cell line was used for the Western blot immunoassay. RESULTS Only five patients (9.4%) showed anti--hsp-70 antibodies: Two presented a sudden sensorineural hearing loss (sudden deafness group), two showed an idiopathic progressive sensorineural hearing loss (idiopathic progressive sensorineural hearing loss group), and one was affected by fluctuating hearing loss (Meniere's disease group). A systemic autoimmune condition was observed in 29.1% of patients with idiopathic progressive sensorineural hearing loss. CONCLUSIONS The low sensitivity of Western blot immunoassay for patients affected by idiopathic progressive sensorineural hearing loss and Meniere's disease may result from either the long time elapsed from the hearing loss and vertigo to the initial examination or from the increased percentage of cases of systemic autoimmune disease present in patients with idiopathic progressive sensorineural hearing loss. More studies to detect the immune-mediated inner ear disease in Western blot immunoassay-negative patients are required.
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Affiliation(s)
- José Ramón García Berrocal
- Servicio de Otorrinolaringología, Clínica Puerta de Hierro, Universidad Autónoma de Madrid, Madrid, Spain.
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