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Cui F, Cao Z, Zhang Q, Cao Z. The protective role of Wnt3a in peroxynitrite-induced damage of cochlear hair cells in vitro. Braz J Otorhinolaryngol 2023; 89:101278. [PMID: 37331234 PMCID: PMC10300296 DOI: 10.1016/j.bjorl.2023.101278] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 04/05/2023] [Accepted: 05/25/2023] [Indexed: 06/20/2023] Open
Abstract
OBJECTIVE To investigate the effect of peroxynitrite on the cultured cochlear hair cells of C57BL/6 P3 mice in vitro as well as the role of Wnt3a, as an activator of the canonical Wnt signaling pathway, underlying the action of such an oxidative stress. METHODS The in vitro primary cultured cochlear hair cells were subjected to l00 μM peroxynitrite and l00 μM peroxynitrite +25 ng/mL Wnt3a for 24 h, the cell survival and morphological changes were examined by immunofluorescence and transmission electron microscopy. RESULTS The number of surviving hair cells was significantly reduced in the 100 μM peroxynitrite group, while it was significantly higher in the Wnt3a + peroxynitrite treated group compared with the peroxynitrite treated group. The transmission electron microscopy showed that exposure to peroxynitrite induced a dramatic decrease in the number of mitochondria and severely disrupted mitochondrial ultrastructure, while Wnt3a clearly diminished the disruption of mitochondrial structure and preserved a higher number of mitochondria. CONCLUSION These results indicated that peroxynitrite could cause oxidative damage to the cochlear hair cells, and low concentrations of Wnt3a has a protective effect against oxidative damage. LEVEL OF EVIDENCE Level 2.
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Affiliation(s)
- Fengyun Cui
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Department of Pathology, Shandong Province, China
| | - Zhimin Cao
- Gao Tang People's Hospital Affiliated to Jining Medical University, Emergency Department, Shandong Province, China
| | - Qianru Zhang
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Department of Pathology, Shandong Province, China
| | - Zhixin Cao
- Shandong Provincial Hospital Affiliated to Shandong First Medical University, Department of Pathology, Shandong Province, China.
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2
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Glover JC, Fritzsch B. Molecular mechanisms governing development of the hindbrain choroid plexus and auditory projection: A validation of the seminal observations of Wilhelm His. IBRO Neurosci Rep 2022; 13:306-313. [PMID: 36247525 PMCID: PMC9561746 DOI: 10.1016/j.ibneur.2022.09.011] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 09/29/2022] [Accepted: 09/29/2022] [Indexed: 11/05/2022] Open
Abstract
Studies by His from 1868 to 1904 delineated the critical role of the dorsal roof plate in the development of the hindbrain choroid plexus, and of the rhombic lips in the development of hindbrain auditory centers. Modern molecular studies have confirmed these observations and placed them in a mechanistic context. Expression of the transcription factor Lmx1a/b is crucial to the development of the hindbrain choroid plexus, and also regulates the expression of Atoh1, a transcription factor that is essential for the formation of the cochlear hair cells and auditory nuclei. By contrast, development of the vestibular hair cells, vestibular ganglion and vestibular nuclei does not depend on Lmx1a/b. These findings demonstrate a common dependence on a specific gene for the hindbrain choroid plexus and the primary auditory projection from hair cells to sensory neurons to hindbrain nuclei. Thus, His' conclusions regarding the origins of specific hindbrain structures are borne out by molecular genetic experiments conducted more than a hundred years later.
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Affiliation(s)
- Joel C. Glover
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
- Norwegian Center for Stem Cell Research, Oslo University Hospital, Oslo, Norway
- Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
- Corresponding author at: Department of Molecular Medicine, University of Oslo, Oslo, Norway.
| | - Bernd Fritzsch
- Department of Biology, University of Iowa, Iowa, IA 52242, USA
- Corresponding author.
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Song Q, Wang J. Effects of the lignan compound (+)-Guaiacin on hair cell survival by activating Wnt/β-Catenin signaling in mouse cochlea. Tissue Cell 2020; 66:101393. [PMID: 32933716 DOI: 10.1016/j.tice.2020.101393] [Citation(s) in RCA: 2] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 05/19/2020] [Accepted: 05/31/2020] [Indexed: 01/25/2023]
Abstract
Wnt/β-Catenin signaling is required for the development and differentiation of cochlear hair cells. Total of 80 natural compounds derived from the FDA-approved Drug Library of Selleck were screened by T-cell factor Reporter Plasmid (TOP)-Flash assay to identify the activation of Wnt/β-Catenin signaling. The mouse cochlear hair cells (HEI-OC1) were treated with cisplatin with or without Guaiacin, and the relative expression of β-Catenin and TRIM33 were detected by qRT-PCR and Western blots. The viability of HEI-OC1 was assayed by MTT method, and mouse cochlear cultures were utilized to detect the Ex vivo survival of cochlear hair cells. Guaiacin was testified to have the most vigorous ability to promote Wnt/β-Catenin signaling among 80 compounds detected, and it can also improve the β-Catenin signaling in mouse cochlear hair cells with up-regulated β-Catenin protein expression, unchanged β-Catenin mRNA expression, and down-regulated TRIM33 expression. Guaiacin increased the viability of HEI-OC1 cells cultured with or without cisplatin, and such a protective effect was also testified in mouse cochlear cultures. Our data indicate that Guaiacin could increase Wnt/β-Catenin signaling by regulating TRIM33/β-Catenin axis, which contributes to the improved survival of cochlear hair cells.
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Affiliation(s)
- Quanfa Song
- Department of Otolaryngology, Weifang City Hanting District People's Hospital, Weifang, 261100, Shandong, China
| | - Junming Wang
- Department of Otolaryngology, Weifang City Hanting District People's Hospital, Weifang, 261100, Shandong, China.
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Basta D, Gröschel M, Strübing I, Boyle P, Fröhlich F, Ernst A, Seidl R. Near-infrared-light pre-treatment attenuates noise-induced hearing loss in mice. PeerJ 2020; 8:e9384. [PMID: 32596055 PMCID: PMC7305775 DOI: 10.7717/peerj.9384] [Citation(s) in RCA: 1] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 05/28/2020] [Indexed: 12/02/2022] Open
Abstract
Noise induced hearing loss (NIHL) is accompanied by a reduction of cochlear hair cells and spiral ganglion neurons. Different approaches have been applied to prevent noise induced apoptosis / necrosis. Physical intervention is one technique currently under investigation. Specific wavelengths within the near-infrared light (NIR)-spectrum are known to influence cytochrome-c-oxidase activity, which leads in turn to a decrease in apoptotic mechanisms. It has been shown recently that NIR can significantly decrease the cochlear hair cell loss if applied daily for 12 days after a noise exposure. However, it is still unclear if a single NIR-treatment, just before a noise exposure, could induce similar protective effects. Therefore, the present study was conducted to investigate the effect of a single NIR-pre-treatment aimed at preventing or limiting NIHL. The cochleae of adult NMRI-mice were pre-treated with NIR-light (808 nm, 120 mW) for 5, 10, 20, 30 or 40 minutes via the external ear canal. All animals were noised exposed immediately after the pre-treatment by broad band noise (5–20 kHz) for 30 minutes at 115 dB SPL. Frequency specific ABR-recordings to determine auditory threshold shift were carried out before the pre-treatment and two weeks after the noise exposure. The amplitude increase for wave IV and cochlear hair cell loss were determined. A further group of similar mice was noise exposed only and served as a control for the NIR pre-exposed groups. Two weeks after noise exposure, the ABR threshold shifts of NIR-treated animals were significantly lower (p < 0.05) than those of the control animals. The significance was at three frequencies for the 5-minute pre-treatment group and across the entire frequency range for all other treatment groups. Due to NIR light, the amplitude of wave four deteriorates significantly less after noise exposure than in controls. The NIR pre-treatment had no effect on the loss of outer hair cells, which was just as high with or without NIR-light pre-exposure. Relative to the entire number of outer hair cells across the whole cochlea, outer hair cell loss was rather negligible. No inner hair cell loss whatever was detected. Our results suggest that a single NIR pre-treatment induces a very effective protection of cochlear structures from noise exposure. Pre-exposure of 10 min seems to emerge as the optimal dosage for our experimental setup. A saturated effect occurred with higher dosage-treatments. These results are relevant for protection of residual hearing in otoneurosurgery such as cochlear implantation.
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Affiliation(s)
- Dietmar Basta
- Department of ENT at ukb, Charité Medical School, University of Berlin, Berlin, Germany
| | - Moritz Gröschel
- Department of ENT at ukb, Charité Medical School, University of Berlin, Berlin, Germany
| | - Ira Strübing
- Department of ENT at ukb, Charité Medical School, University of Berlin, Berlin, Germany
| | | | - Felix Fröhlich
- Department of ENT at ukb, Charité Medical School, University of Berlin, Berlin, Germany
| | - Arne Ernst
- Department of ENT at ukb, Charité Medical School, University of Berlin, Berlin, Germany
| | - Rainer Seidl
- Department of ENT at ukb, Charité Medical School, University of Berlin, Berlin, Germany
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Abstract
Disabling hearing loss is the most common sensorineural disability worldwide. It affects around 466 million people and its incidence is expected to rise to around 900 million people by 2050, according to World Health Organization estimates. Most cases of hearing impairment are due to the degeneration of hair cells (HCs) in the cochlea, mechano-receptors that transduce incoming sound information into electrical signals that are sent to the brain. Damage to these cells is mainly caused by exposure to aminoglycoside antibiotics and to some anti-cancer drugs such as cisplatin, loud sounds, age, infections and genetic mutations. Hearing deficits may also result from damage to the spiral ganglion neurons that innervate cochlear HCs. Differently from what is observed in avian and non-mammalian species, there is no regeneration of missing sensory cell types in the adult mammalian cochlea, what makes hearing loss an irreversible process. This review summarizes the research that has been conducted with the aim of developing cell-based strategies that lead to sensory cell replacement in the adult cochlea and, ultimately, to hearing restoration. Two main lines of research are discussed, one directed toward the transplantation of exogenous replacement cells into the damaged tissue, and another that aims at reactivating the regenerative potential of putative progenitor cells in the adult inner ear. Results from some of the studies that have been conducted are presented and the advantages and drawbacks of the various approaches discussed.
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Wang FS, Nie G, Huang CC, Li Q, Li T, Zou Y, Zhang S, Ceng X. Investigation of cochlear hair cells and the perception of ultrasound signals in guinea pigs. Cell Mol Biol (Noisy-le-grand) 2018; 64:44-49. [PMID: 30213288] [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] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 08/14/2018] [Accepted: 08/05/2018] [Indexed: 06/08/2023]
Abstract
We established a specific ultrasound frequency-dependent model of cochlear injury using bone conduction ultrasounds in the inner ear of guinea pigs at 50 kHz and 83 kHz, to explore the effects of bone conduction ultrasound in the cochlea. To establish a unilateral cochlear damage model, the unilateral cochlea was destroyed. The control group consisted of 50 kHz and 83 kHz bone conduction ultrasounds in unaltered guinea pigs. In each group, cerebral blood oxygenation level dependent (BOLD) effects were determined by functional magnetic resonance imaging (fMRI). The cochlear outer hair cell motor protein, Prestin, and the microfilament protein, F-Actin, were detected. We found that bone conduction ultrasound irradiation at 50 kHz and 83 kHz on the guinea pig inner ear for six hours leads to hair cell damage. Furthermore, low frequency bone conduction ultrasound induces major damage to outer hair cells, while high frequency ultrasound damages both internal and external hair cells. fMRI analysis of cerebral BLOD effects revealed an affected cerebral cortex region of interest (ROI) of 4 and 2, respectively, for the normal control group at 50 kHz or 83 kHz, and 2 for the 83 kHz bone conduction ultrasound cochlear injury group, while 50 kHz bone conduction ultrasound failed to induce the cortical ROI within injury model. Results reveal that the spatial location of guinea pig cochlear hair cells determines coding function for lower ultrasound frequencies, and high frequency bone conduction ultrasound may affect the cochlear spiral ganglion or cranial nerve nucleus in bone conduction ultrasound periphery perception.
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Affiliation(s)
- Fu-Sen Wang
- Department of Otorhinolaryngology, Southern Medical University Affiliated Shenzhen Baoan Hospital, Shenzhen, China
| | - Guohui Nie
- Department of Otorhinolaryngology, the Second People's Hospital of Shenzhen city, Shenzhen, China
| | - Cheng-Cheng Huang
- Department of Otorhinolaryngology, Wuhan General hospital of PLA, Wuhan, China
| | - Qian Li
- Chinese People's Liberation Army 301 Hospital ENT Research Institute, Beijing, China
| | - Tiegang Li
- Molecular Imaging Centre, Institute of Materia Medical, Chinese Academy of Medical Sciences, Beijing, China
| | - Yuee Zou
- Department of electrocardiogram, Southern Medical University Affiliated Shenzhen Baoan Hospital, Shenzhen, China
| | - Shaoyan Zhang
- Department of Otorhinolaryngology, Southern Medical University Affiliated Shenzhen Baoan Hospital, Shenzhen, China
| | - Xinyu Ceng
- Department of Otorhinolaryngology, Southern Medical University Affiliated Shenzhen Baoan Hospital, Shenzhen, China
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Monsanto RDC, Schachern P, Paparella MM, Cureoglu S, Penido NDO. Progression of changes in the sensorial elements of the cochlear and peripheral vestibular systems: The otitis media continuum. Hear Res 2017; 351:2-10. [PMID: 28578877 DOI: 10.1016/j.heares.2017.05.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [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: 01/18/2017] [Revised: 04/10/2017] [Accepted: 05/03/2017] [Indexed: 12/16/2022]
Abstract
Our study aimed to evaluate pathologic changes in the cochlear (inner and outer hair cells and stria vascularis) and vestibular (vestibular hair cells, dark, and transitional cells) sensorial elements in temporal bones from donors who had otitis media. We studied 40 temporal bones from such donors, which were categorized in serous otitis media (SOM), serous-purulent otitis media (SPOM), mucoid/mucoid-purulent otitis media (MOM/MPOM), and chronic otitis media (COM); control group comprised 10 nondiseased temporal bones. We found significant loss of inner and outer cochlear hair cells in the basal turn of the SPOM, MOM/MPOM and COM groups; significant loss of vestibular hair cells was observed in the MOM/MPOM and COM groups. All otitis media groups had smaller mean area of the stria vascularis in the basal turn of the cochlea when compared to controls. In conclusion, our study demonstrated more severe pathologic changes in the later stages of the continuum of otitis media (MOM/MPOM and COM). Those changes seem to progress from the basal turn of the cochlea (stria vascularis, then inner and outer hair cells) to the middle turn of the cochlea and to the saccule and utricle in the MOM/MPOM and COM stages.
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Affiliation(s)
- Rafael da Costa Monsanto
- Department of Otolaryngology, University of Minnesota, 2001 6th St. SE, Lions Research Building, Room 210, Otopathology Laboratory, Minneapolis, MN 55455, USA; Department of Otorhinolaryngology Head and Neck Surgery, Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina, Rua dos Otonis, 700 - Piso Superior - Vila Clementino, São Paulo, SP 04025 002, Brazil
| | - Patricia Schachern
- Department of Otolaryngology, University of Minnesota, 2001 6th St. SE, Lions Research Building, Room 210, Otopathology Laboratory, Minneapolis, MN 55455, USA
| | - Michael M Paparella
- Department of Otolaryngology, University of Minnesota, 2001 6th St. SE, Lions Research Building, Room 210, Otopathology Laboratory, Minneapolis, MN 55455, USA
| | - Sebahattin Cureoglu
- Department of Otolaryngology, University of Minnesota, 2001 6th St. SE, Lions Research Building, Room 210, Otopathology Laboratory, Minneapolis, MN 55455, USA.
| | - Norma de Oliveira Penido
- Department of Otorhinolaryngology Head and Neck Surgery, Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina, Rua dos Otonis, 700 - Piso Superior - Vila Clementino, São Paulo, SP 04025 002, Brazil
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8
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da Silva VG, de Oliveira CACP, Tauil PL, de Castro Silva IM, Sampaio ALL. Amplified music exposure carries risks to hearing. Int J Pediatr Otorhinolaryngol 2017; 93:117-122. [PMID: 28109481 DOI: 10.1016/j.ijporl.2016.12.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [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: 09/23/2016] [Revised: 12/18/2016] [Accepted: 12/21/2016] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To investigate the association between changes in the outer hair cells and exposure to amplified music in a group of high-school students. MATERIALS AND METHODS In this retrospective, case-control study, 86 subjects underwent audiometry, immittance audiometry, and distortion-product otoacoustic emission tests. The subjects were questioned about their listening habits and divided into 2 groups: exposed and unexposed. RESULTS Most of the subjects had reduced function in their outer hair cells, mainly beginning at 8 kHz. Among 60 subjects-30 cases and 30 controls-75% were considered exposed and 25% unexposed. The exposed subjects were 9.33 times more likely to have altered outer hair cells than the unexposed subjects were. CONCLUSION Exposure to amplified music is associated with reduced function in the hair cells.
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Encke J, Kreh J, Völk F, Hemmert W. [Conversion of sound into auditory nerve action potentials]. HNO 2016; 64:808-814. [PMID: 27785535 DOI: 10.1007/s00106-016-0258-z] [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] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Outer hair cells play a major role in the hearing process: they amplify the motion of the basilar membrane up to a 1000-fold and at the same time sharpen the excitation patterns. These patterns are converted by inner hair cells into action potentials of the auditory nerve. Outer hair cells are delicate structures and easily damaged, e. g., by overexposure to noise. Hearing aids can amplify the amplitude of the excitation patterns, but they cannot restore their degraded frequency selectivity. Noise overexposure also leads to delayed degeneration of auditory nerve fibers, particularly those with low a spontaneous rate, which are important for the coding of sound in noise. However, this loss cannot be diagnosed by pure-tone audiometry.
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Affiliation(s)
- J Encke
- Bioanaloge Informationsverarbeitung, Zentralinstitut für Medizintechnik, Technische Universität München, Boltzmannstr. 11, 85748, Garching, Deutschland
| | - J Kreh
- Bioanaloge Informationsverarbeitung, Zentralinstitut für Medizintechnik, Technische Universität München, Boltzmannstr. 11, 85748, Garching, Deutschland
| | - F Völk
- Bioanaloge Informationsverarbeitung, Zentralinstitut für Medizintechnik, Technische Universität München, Boltzmannstr. 11, 85748, Garching, Deutschland
| | - W Hemmert
- Bioanaloge Informationsverarbeitung, Zentralinstitut für Medizintechnik, Technische Universität München, Boltzmannstr. 11, 85748, Garching, Deutschland.
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10
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Abstract
The sensory epithelium of the mammalian inner ear contains two types of mechanosensory cells: inner (IHC) and outer hair cells (OHC). They both transduce mechanical force generated by sound waves into electrical signals. In their apical end, these cells possess a set of stereocilia representing the mechanosensing organelles. IHC are responsible for detecting sounds and transmitting the acoustic information to the brain by converting graded depolarization into trains of action potentials in auditory nerve fibers. OHC are responsible for the active mechanical amplification process that leads to the fine tuning and high sensitivity of the mammalian inner ear. This active amplification is the consequence of the ability of OHC to alter their cell length in response to changes in membrane potential, and is controlled by an efferent inhibitory innervation. Medial olivocochlear efferent fibers, originating in the brainstem, synapse directly at the base of OHC and release acetylcholine. A very special type of nicotinic receptor, assembled by α9α10 subunits, participates in this synapse. Here we review recent knowledge and the role of both afferent and efferent synapse in the inner ear.
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Affiliation(s)
- Juan D Goutman
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, "Dr. Héctor N Torres" (CONICET-UBA), Vuelta de Obligado 2490, Buenos Aires, Argentina.
| | - A Belén Elgoyhen
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, "Dr. Héctor N Torres" (CONICET-UBA), Vuelta de Obligado 2490, Buenos Aires, Argentina; Tercera Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, Buenos Aires, Argentina
| | - María Eugenia Gómez-Casati
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, "Dr. Héctor N Torres" (CONICET-UBA), Vuelta de Obligado 2490, Buenos Aires, Argentina; Tercera Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, Buenos Aires, Argentina.
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Newman AJ, Hayes SH, Rao AS, Allman BL, Manohar S, Ding D, Stolzberg D, Lobarinas E, Mollendorf JC, Salvi R. Low-cost blast wave generator for studies of hearing loss and brain injury: blast wave effects in closed spaces. J Neurosci Methods 2015; 242:82-92. [PMID: 25597910 DOI: 10.1016/j.jneumeth.2015.01.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [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: 04/02/2014] [Revised: 12/12/2014] [Accepted: 01/07/2015] [Indexed: 01/24/2023]
Abstract
BACKGROUND Military personnel and civilians living in areas of armed conflict have increased risk of exposure to blast overpressures that can cause significant hearing loss and/or brain injury. The equipment used to simulate comparable blast overpressures in animal models within laboratory settings is typically very large and prohibitively expensive. NEW METHOD To overcome the fiscal and space limitations introduced by previously reported blast wave generators, we developed a compact, low-cost blast wave generator to investigate the effects of blast exposures on the auditory system and brain. RESULTS The blast wave generator was constructed largely from off the shelf components, and reliably produced blasts with peak sound pressures of up to 198dB SPL (159.3kPa) that were qualitatively similar to those produced from muzzle blasts or explosions. Exposure of adult rats to 3 blasts of 188dB peak SPL (50.4kPa) resulted in significant loss of cochlear hair cells, reduced outer hair cell function and a decrease in neurogenesis in the hippocampus. COMPARISON TO EXISTING METHODS Existing blast wave generators are typically large, expensive, and are not commercially available. The blast wave generator reported here provides a low-cost method of generating blast waves in a typical laboratory setting. CONCLUSIONS This compact blast wave generator provides scientists with a low cost device for investigating the biological mechanisms involved in blast wave injury to the rodent cochlea and brain that may model many of the damaging effects sustained by military personnel and civilians exposed to intense blasts.
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Affiliation(s)
- Andrew J Newman
- Department of Mechanical and Aerospace Engineering, University at Buffalo, The State University of New York, Buffalo, NY, United States.
| | - Sarah H Hayes
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, University at Buffalo, The State University of New York, Buffalo, NY, United States.
| | - Abhiram S Rao
- Department of Mechanical and Aerospace Engineering, University at Buffalo, The State University of New York, Buffalo, NY, United States.
| | - Brian L Allman
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, University at Buffalo, The State University of New York, Buffalo, NY, United States.
| | - Senthilvelan Manohar
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, University at Buffalo, The State University of New York, Buffalo, NY, United States.
| | - Dalian Ding
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, University at Buffalo, The State University of New York, Buffalo, NY, United States.
| | - Daniel Stolzberg
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, University at Buffalo, The State University of New York, Buffalo, NY, United States.
| | - Edward Lobarinas
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, University at Buffalo, The State University of New York, Buffalo, NY, United States.
| | - Joseph C Mollendorf
- Department of Mechanical and Aerospace Engineering, University at Buffalo, The State University of New York, Buffalo, NY, United States.
| | - Richard Salvi
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, University at Buffalo, The State University of New York, Buffalo, NY, United States.
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Dettling J, Franz C, Zimmermann U, Lee SC, Bress A, Brandt N, Feil R, Pfister M, Engel J, Flamant F, Rüttiger L, Knipper M. Autonomous functions of murine thyroid hormone receptor TRα and TRβ in cochlear hair cells. Mol Cell Endocrinol 2014; 382:26-37. [PMID: 24012852 DOI: 10.1016/j.mce.2013.08.025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 08/22/2013] [Accepted: 08/29/2013] [Indexed: 11/18/2022]
Abstract
Thyroid hormone acts on gene transcription by binding to its nuclear receptors TRα1 and TRβ. Whereas global deletion of TRβ causes deafness, global TRα-deficient mice have normal hearing thresholds. Since the individual roles of the two receptors in cochlear hair cells are still unclear, we generated mice with a hair cell-specific mutation of TRα1 or deletion of TRβ using the Cre-loxP system. Hair cell-specific TRβ mutant mice showed normal hearing thresholds but delayed BK channel expression in inner hair cells, slightly stronger outer hair cell function, and slightly reduced amplitudes of auditory brainstem responses. In contrast, hair cell-specific TRα mutant mice showed normal timing of BK channel expression, slightly reduced outer hair cell function, and slightly enhanced amplitudes of auditory brainstem responses. Our data demonstrate that TRβ-related deafness originates outside of hair cells and that TRα and TRβ play opposing, non-redundant roles in hair cells. A role for thyroid hormone receptors in controlling key regulators that shape signal transduction during development is discussed. Thyroid hormone may act through different thyroid hormone receptor activities to permanently alter the sensitivity of auditory neurotransmission.
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Affiliation(s)
- Juliane Dettling
- Molecular Physiology of Hearing, Hearing Research Centre Tübingen (THRC), Department of Otolaryngology, University of Tübingen, Elfriede-Aulhorn-Str. 5, 72076 Tübingen, Germany
| | - Christoph Franz
- Molecular Physiology of Hearing, Hearing Research Centre Tübingen (THRC), Department of Otolaryngology, University of Tübingen, Elfriede-Aulhorn-Str. 5, 72076 Tübingen, Germany
| | - Ulrike Zimmermann
- Molecular Physiology of Hearing, Hearing Research Centre Tübingen (THRC), Department of Otolaryngology, University of Tübingen, Elfriede-Aulhorn-Str. 5, 72076 Tübingen, Germany
| | - Sze Chim Lee
- Molecular Physiology of Hearing, Hearing Research Centre Tübingen (THRC), Department of Otolaryngology, University of Tübingen, Elfriede-Aulhorn-Str. 5, 72076 Tübingen, Germany
| | - Andreas Bress
- Molecular Genetics, THRC, Department of Otolaryngology, University of Tübingen, Elfriede-Aulhorn-Str. 5, 72076 Tübingen, Germany
| | - Niels Brandt
- Department of Biophysics, Saarland University, 66421 Homburg/Saar, Germany
| | - Robert Feil
- Department of Signal Transduction & Transgenic Models, Interfaculty Institute of Biochemistry, University of Tübingen, Hoppe-Seyler-Str. 4, 72076 Tübingen, Germany
| | - Markus Pfister
- Molecular Genetics, THRC, Department of Otolaryngology, University of Tübingen, Elfriede-Aulhorn-Str. 5, 72076 Tübingen, Germany
| | - Jutta Engel
- Department of Biophysics, Saarland University, 66421 Homburg/Saar, Germany
| | - Frédéric Flamant
- Institut de Génomique Fonctionnelle, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon cedex 07, Lyon, France
| | - Lukas Rüttiger
- Molecular Physiology of Hearing, Hearing Research Centre Tübingen (THRC), Department of Otolaryngology, University of Tübingen, Elfriede-Aulhorn-Str. 5, 72076 Tübingen, Germany
| | - Marlies Knipper
- Molecular Physiology of Hearing, Hearing Research Centre Tübingen (THRC), Department of Otolaryngology, University of Tübingen, Elfriede-Aulhorn-Str. 5, 72076 Tübingen, Germany.
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