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Ismail Mohamad N, Santra P, Park Y, Matthews IR, Taketa E, Chan DK. Synaptic ribbon dynamics after noise exposure in the hearing cochlea. Commun Biol 2024; 7:421. [PMID: 38582813 PMCID: PMC10998851 DOI: 10.1038/s42003-024-06067-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 03/18/2024] [Indexed: 04/08/2024] Open
Abstract
Moderate noise exposure induces cochlear synaptopathy, the loss of afferent ribbon synapses between cochlear hair cells and spiral ganglion neurons, which is associated with functional hearing decline. Prior studies have demonstrated noise-induced changes in the distribution and number of synaptic components, but the dynamic changes that occur after noise exposure have not been directly visualized. Here, we describe a live imaging model using RIBEYE-tagRFP to enable direct observation of pre-synaptic ribbons in mature hearing mouse cochleae after synaptopathic noise exposure. Ribbon number does not change, but noise induces an increase in ribbon volume as well as movement suggesting unanchoring from synaptic tethers. A subgroup of basal ribbons displays concerted motion towards the cochlear nucleus with subsequent migration back to the cell membrane after noise cessation. Understanding the immediate dynamics of synaptic damage after noise exposure may facilitate identification of specific target pathways to treat cochlear synaptopathy.
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Affiliation(s)
- Noura Ismail Mohamad
- Department of Otolaryngology-Head and Neck Surgery, University of California, San Francisco, San Francisco, CA, USA
| | - Peu Santra
- Department of Otolaryngology-Head and Neck Surgery, University of California, San Francisco, San Francisco, CA, USA
| | - Yesai Park
- Department of Otolaryngology-Head and Neck Surgery, University of California, San Francisco, San Francisco, CA, USA
| | - Ian R Matthews
- Department of Otolaryngology-Head and Neck Surgery, University of California, San Francisco, San Francisco, CA, USA
| | - Emily Taketa
- Department of Otolaryngology-Head and Neck Surgery, University of California, San Francisco, San Francisco, CA, USA
| | - Dylan K Chan
- Department of Otolaryngology-Head and Neck Surgery, University of California, San Francisco, San Francisco, CA, USA.
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2
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Zhuang H, Li Q, Sun C, Xu D, Gan G, Zhang C, Chen C, Yuan Y, Liu L, Xiao Y, Yao X, Wang C, Kang X, Yang C, Zhao J, Chen W, Wang J, Li J, Luo C, Wang J, Jia X, Yu Z, Liu L. Voluntary wheel exercise ameliorates cognitive impairment, hippocampal neurodegeneration and microglial abnormalities preceded by demyelination in a male mouse model of noise-induced hearing loss. Brain Behav Immun 2023; 114:325-348. [PMID: 37683962 DOI: 10.1016/j.bbi.2023.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 08/23/2023] [Accepted: 09/05/2023] [Indexed: 09/10/2023] Open
Abstract
Acquired peripheral hearing loss (APHL) in midlife has been identified as the greatest modifiable risk factor for dementia; however, the pathophysiological neural mechanisms linking APHL with an increased risk of dementia remain to be elucidated. Here, in an adult male mouse model of noise-induced hearing loss (NIHL), one of the most common forms of APHL, we demonstrated accelerated age-related cognitive decline and hippocampal neurodegeneration during a 6-month follow-up period, accompanied by progressive hippocampal microglial aberrations preceded by immediate-onset transient elevation in serum glucocorticoids and delayed-onset sustained myelin disruption in the hippocampus. Pretreatment with the glucocorticoid receptor antagonist RU486 before stressful noise exposure partially mitigated the early activation of hippocampal microglia, which were present at 7 days post noise exposure (7DPN), but had no impact on later microglial aberrations, hippocampal neurodegeneration, or cognitive decline exhibited at 1 month post noise exposure (1MPN). One month of voluntary wheel exercise following noise exposure barely affected either the hearing threshold shift or hippocampal myelin changes but effectively countered cognitive impairment and the decline in hippocampal neurogenesis in NIHL mice at 1MPN, paralleled by the normalization of microglial morphology, which coincided with a reduction in microglial myelin inclusions and a restoration of microglial hypoxia-inducible factor-1α (HIF1α) expression. Our results indicated that accelerated cognitive deterioration and hippocampal neuroplastic decline following NIHL are most likely driven by the maladaptive response of hippocampal microglia to myelin damage secondary to hearing loss, and we also demonstrated the potential of voluntary physical exercise as a promising and cost-effective strategy to alleviate the detrimental impact of APHL on cognitive function and thus curtail the high and continuously increasing global burden of dementia. Furthermore, the findings of the present study highlight the contribution of myelin debris overload to microglial malfunction and identify the microglial HIF1α-related pathway as an attractive candidate for future comprehensive investigation to obtain a more definitive picture of the underlying mechanisms linking APHL and dementia.
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Affiliation(s)
- Hong Zhuang
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Qian Li
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Congli Sun
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Dan Xu
- School of Public Health, Southeast University, Nanjing 210009, China
| | - Guangming Gan
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Chenchen Zhang
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Chen Chen
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Yang Yuan
- Department of Endocrinology, Zhongda Hospital, Medical School, Southeast University, Nanjing 210009, China
| | - Linchen Liu
- Department of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, China
| | - Yu Xiao
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Xiuting Yao
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Conghui Wang
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Xiaoming Kang
- School of Life Science and Technology, Southeast University, Nanjing 210009, China
| | - Chenxi Yang
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Jingyi Zhao
- School of Life Science and Technology, Southeast University, Nanjing 210009, China
| | - Wenhao Chen
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Jiatang Wang
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Jinyu Li
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Caichen Luo
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Jie Wang
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Xirui Jia
- School of Life Science and Technology, Southeast University, Nanjing 210009, China
| | - Zhehao Yu
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Lijie Liu
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China.
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3
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Hardy KA, Hart DM, Rosen MJ. Early-life stress affects Mongolian gerbil interactions with conspecific vocalizations in a sex-specific manner. Front Behav Neurosci 2023; 17:1128586. [PMID: 37234406 PMCID: PMC10206074 DOI: 10.3389/fnbeh.2023.1128586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 04/17/2023] [Indexed: 05/28/2023] Open
Abstract
During development, early-life stress (ELS) impairs cognition, learning, and emotional regulation, in part by disrupting neural circuitry in regions underlying these higher-order functions. In addition, our recent work indicates that ELS also alters simple sensory perception: ELS impaired auditory perception and neural encoding of short gaps in sounds, which are essential for vocal communication. The combination of higher-order and basic sensory disruption suggests that ELS is likely to affect both the perception and interpretation of communication signals. We tested this hypothesis by measuring behavioral responses to conspecific vocalizations (those emitted by other gerbils) in ELS and untreated Mongolian gerbils. Because stress effects often differ by sex, we separately examined females and males. To induce ELS, pups were intermittently maternally separated and restrained from post-natal days (P) 9-24, a time window when the auditory cortex is most sensitive to external disruption. We measured the approach responses of juvenile (P31-32) gerbils to two types of conspecific vocalizations: an alarm call, which is emitted to alert other gerbils of a potential threat, and the prosocial contact call, which is emitted near familiar gerbils, especially after separation. Control males, Control females, and ELS females approached a speaker emitting pre-recorded alarm calls, while ELS males avoided this source, suggesting that ELS affects the response to alarm calls in male gerbils. During playback of the pre-recorded contact call, Control females and ELS males avoided the sound source, while Control males neither approached nor avoided, and ELS females approached the sound. These differences cannot be accounted for by changes in locomotion or baseline arousal. However, ELS gerbils slept more during playback, suggesting that ELS may reduce arousal during vocalization playback. Further, male gerbils made more errors than females on a measure of working memory, but the sex difference of cognition in this context may stem from novelty aversion rather than impaired memory. These data indicate that ELS influences behavioral responses to ethologically relevant communication sounds in a sex-specific manner, and are among the first to demonstrate an altered response to auditory stimuli following ELS. Such changes may arise from differences in auditory perception, cognition, or a combination of factors, and suggest that ELS may affect auditory communication in human adolescents.
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Affiliation(s)
- Kate A. Hardy
- Department of Anatomy and Neurobiology, Hearing Research Group, Northeast Ohio Medical University, Rootstown, OH, United States
- Department of Biological Sciences, Brain Health Research Institute, Kent State University, Kent, OH, United States
| | - Denise M. Hart
- Department of Anatomy and Neurobiology, Hearing Research Group, Northeast Ohio Medical University, Rootstown, OH, United States
| | - Merri J. Rosen
- Department of Anatomy and Neurobiology, Hearing Research Group, Northeast Ohio Medical University, Rootstown, OH, United States
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Ye Y, Mattingly MM, Sunthimer MJ, Gay JD, Rosen MJ. Early-Life Stress Impairs Perception and Neural Encoding of Rapid Signals in the Auditory Pathway. J Neurosci 2023; 43:3232-3244. [PMID: 36973014 PMCID: PMC10162457 DOI: 10.1523/jneurosci.1787-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 01/24/2023] [Accepted: 03/03/2023] [Indexed: 03/29/2023] Open
Abstract
During developmental critical periods (CPs), early-life stress (ELS) induces cognitive deficits and alters neural circuitry in regions underlying learning, memory, and attention. Mechanisms underlying critical period plasticity are shared by sensory cortices and these higher neural regions, suggesting that sensory processing may also be vulnerable to ELS. In particular, the perception and auditory cortical (ACx) encoding of temporally-varying sounds both mature gradually, even into adolescence, providing an extended postnatal window of susceptibility. To examine the effects of ELS on temporal processing, we developed a model of ELS in the Mongolian gerbil, a well-established model for auditory processing. In both male and female animals, ELS induction impaired the behavioral detection of short gaps in sound, which are critical for speech perception. This was accompanied by reduced neural responses to gaps in auditory cortex, the auditory periphery, and auditory brainstem. ELS thus degrades the fidelity of sensory representations available to higher regions, and could contribute to well-known ELS-induced problems with cognition.SIGNIFICANCE STATEMENT In children and animal models, early-life stress (ELS) leads to deficits in cognition, including problems with learning, memory, and attention. Such problems could arise in part from a low-fidelity representation of sensory information available to higher-level neural regions. Here, we demonstrate that ELS degrades sensory responses to rapid variations in sound at multiple levels of the auditory pathway, and concurrently impairs perception of these rapidly-varying sounds. As these sound variations are intrinsic to speech, ELS may thus pose a challenge to communication and cognition through impaired sensory encoding.
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Affiliation(s)
- Yi Ye
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, 44272
- Brain Health Research Institute, Kent State University, Kent, Ohio, 44242
| | - Michelle M Mattingly
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, 44272
| | - Matthew J Sunthimer
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, 44272
| | - Jennifer D Gay
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, 44272
- Department of Otolaryngology, Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey, 08901
| | - Merri J Rosen
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, 44272
- Brain Health Research Institute, Kent State University, Kent, Ohio, 44242
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Barnes CC, Yee KT, Vetter DE. Conditional Ablation of Glucocorticoid and Mineralocorticoid Receptors from Cochlear Supporting Cells Reveals Their Differential Roles for Hearing Sensitivity and Dynamics of Recovery from Noise-Induced Hearing Loss. Int J Mol Sci 2023; 24:3320. [PMID: 36834731 PMCID: PMC9961551 DOI: 10.3390/ijms24043320] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023] Open
Abstract
Endogenous glucocorticoids (GC) are known to modulate basic elements of cochlear physiology. These include both noise-induced injury and circadian rhythms. While GC signaling in the cochlea can directly influence auditory transduction via actions on hair cells and spiral ganglion neurons, evidence also indicates that GC signaling exerts effects via tissue homeostatic processes that can include effects on cochlear immunomodulation. GCs act at both the glucocorticoid receptor (GR) and the mineralocorticoid receptor (MR). Most cell types in the cochlea express both receptors sensitive to GCs. The GR is associated with acquired sensorineural hearing loss (SNHL) through its effects on both gene expression and immunomodulatory programs. The MR has been associated with age-related hearing loss through dysfunction of ionic homeostatic balance. Cochlear supporting cells maintain local homeostatic requirements, are sensitive to perturbation, and participate in inflammatory signaling. Here, we have used conditional gene manipulation techniques to target Nr3c1 (GR) or Nr3c2 (MR) for tamoxifen-induced gene ablation in Sox9-expressing cochlear supporting cells of adult mice to investigate whether either of the receptors sensitive to GCs plays a role in protecting against (or exacerbating) noise-induced cochlear damage. We have selected mild intensity noise exposure to examine the role of these receptors related to more commonly experienced noise levels. Our results reveal distinct roles of these GC receptors for both basal auditory thresholds prior to noise exposure and during recovery from mild noise exposure. Prior to noise exposure, auditory brainstem responses (ABRs) were measured in mice carrying the floxed allele of interest and the Cre recombinase transgene, but not receiving tamoxifen injections (defined as control (no tamoxifen treatment), versus conditional knockout (cKO) mice, defined as mice having received tamoxifen injections. Results revealed hypersensitive thresholds to mid- to low-frequencies after tamoxifen-induced GR ablation from Sox9-expressing cochlear supporting cells compared to control (no tamoxifen) mice. GR ablation from Sox9-expressing cochlear supporting cells resulted in a permanent threshold shift in mid-basal cochlear frequency regions after mild noise exposure that produced only a temporary threshold shift in both control (no tamoxifen) f/fGR:Sox9iCre+ and heterozygous f/+GR:Sox9iCre+ tamoxifen-treated mice. A similar comparison of basal ABRs measured in control (no tamoxifen) and tamoxifen-treated, floxed MR mice prior to noise exposure indicated no difference in baseline thresholds. After mild noise exposure, MR ablation was initially associated with a complete threshold recovery at 22.6 kHz by 3 days post-noise. Threshold continued to shift to higher sensitivity over time such that by 30 days post-noise exposure the 22.6 kHz ABR threshold was 10 dB more sensitive than baseline. Further, MR ablation produced a temporary reduction in peak 1 neural amplitude one day post-noise. While supporting cell GR ablation trended towards reducing numbers of ribbon synapses, MR ablation reduced ribbon synapse counts but did not exacerbate noise-induced damage including synapse loss at the experimental endpoint. GR ablation from the targeted supporting cells increased the basal resting number of Iba1-positive (innate) immune cells (no noise exposure) and decreased the number of Iba1-positive cells seven days following noise exposure. MR ablation did not alter innate immune cell numbers at seven days post-noise exposure. Taken together, these findings support differential roles of cochlear supporting cell MR and GR expression at basal, resting conditions and especially during recovery from noise exposure.
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Affiliation(s)
- Charles C. Barnes
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Kathleen T. Yee
- Department of Otolaryngology–Head and Neck Surgery, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Douglas E. Vetter
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS 39216, USA
- Department of Otolaryngology–Head and Neck Surgery, University of Mississippi Medical Center, Jackson, MS 39216, USA
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Savitska D, Hess M, Calis D, Marchetta P, Harasztosi C, Fink S, Eckert P, Ruth P, Rüttiger L, Knipper M, Singer W. Stress Affects Central Compensation of Neural Responses to Cochlear Synaptopathy in a cGMP-Dependent Way. Front Neurosci 2022; 16:864706. [PMID: 35968392 PMCID: PMC9372611 DOI: 10.3389/fnins.2022.864706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 06/16/2022] [Indexed: 11/13/2022] Open
Abstract
In light of the increasing evidence supporting a link between hearing loss and dementia, it is critical to gain a better understanding of the nature of this relationship. We have previously observed that following cochlear synaptopathy, the temporal auditory processing (e.g., auditory steady state responses, ASSRs), is sustained when reduced auditory input is centrally compensated. This central compensation process was linked to elevated hippocampal long-term potentiation (LTP). We further observed that, independently of age, central responsiveness to cochlear synaptopathy can differ, resulting in either a low or high capacity to compensate for the reduced auditory input. Lower central compensation resulted in poorer temporal auditory processing, reduced hippocampal LTP, and decreased recruitment of activity-dependent brain-derived neurotrophic factor (BDNF) expression in hippocampal regions (low compensators). Higher central compensation capacity resulted in better temporal auditory processing, higher LTP responses, and increased activity-dependent BDNF expression in hippocampal regions. Here, we aimed to identify modifying factors that are potentially responsible for these different central responses. Strikingly, a poorer central compensation capacity was linked to lower corticosterone levels in comparison to those of high compensators. High compensators responded to repeated placebo injections with elevated blood corticosterone levels, reduced auditory brainstem response (ABR) wave I amplitude, reduced inner hair cell (IHC) ribbon number, diminished temporal processing, reduced LTP responses, and decreased activity-dependent hippocampal BDNF expression. In contrast, the same stress exposure through injection did not elevate blood corticosterone levels in low compensators, nor did it reduce IHC ribbons, ABR wave I amplitude, ASSR, LTP, or BDNF expression as seen in high compensators. Interestingly, in high compensators, the stress-induced responses, such as a decline in ABR wave I amplitude, ASSR, LTP, and BDNF could be restored through the “memory-enhancing” drug phosphodiesterase 9A inhibitor (PDE9i). In contrast, the same treatment did not improve these aspects in low compensators. Thus, central compensation of age-dependent cochlear synaptopathy is a glucocorticoid and cyclic guanosine-monophosphate (cGMP)-dependent neuronal mechanism that fails upon a blunted stress response.
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Affiliation(s)
- Daria Savitska
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Morgan Hess
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Dila Calis
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Philine Marchetta
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Csaba Harasztosi
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Stefan Fink
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Philipp Eckert
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Peter Ruth
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Lukas Rüttiger
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Marlies Knipper
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
- *Correspondence: Marlies Knipper
| | - Wibke Singer
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
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Marchetta P, Eckert P, Lukowski R, Ruth P, Singer W, Rüttiger L, Knipper M. Loss of central mineralocorticoid or glucocorticoid receptors impacts auditory nerve processing in the cochlea. iScience 2022; 25:103981. [PMID: 35281733 PMCID: PMC8914323 DOI: 10.1016/j.isci.2022.103981] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/26/2022] [Accepted: 02/21/2022] [Indexed: 02/08/2023] Open
Abstract
The key auditory signature that may associate peripheral hearing with central auditory cognitive defects remains elusive. Suggesting the involvement of stress receptors, we here deleted the mineralocorticoid and glucocorticoid receptors (MR and GR) using a CaMKIIα-based tamoxifen-inducible CreERT2/loxP approach to generate mice with single or double deletion of central but not cochlear MR and GR. Hearing thresholds of MRGRCaMKIIαCreERT2 conditional knockouts (cKO) were unchanged, whereas auditory nerve fiber (ANF) responses were larger and faster and auditory steady state responses were improved. Subsequent analysis of single MR or GR cKO revealed discrete roles for both, central MR and GR on cochlear functions. Limbic MR deletion reduced inner hair cell (IHC) ribbon numbers and ANF responses. In contrast, GR deletion shortened the latency and improved the synchronization to amplitude-modulated tones without affecting IHC ribbon numbers. These findings imply that stress hormone-dependent functions of central MR/GR contribute to “precognitive” sound processing in the cochlea. Top-down MR/GR signaling differentially contributes to cochlear sound processing Limbic MR stimulates auditory nerve fiber discharge rates Central GR deteriorates auditory nerve fiber synchrony
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Affiliation(s)
- Philine Marchetta
- University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | - Philipp Eckert
- University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | - Robert Lukowski
- University of Tübingen, Institute of Pharmacy, Pharmacology, Toxicology and Clinical Pharmacy, 72076 Tübingen, Germany
| | - Peter Ruth
- University of Tübingen, Institute of Pharmacy, Pharmacology, Toxicology and Clinical Pharmacy, 72076 Tübingen, Germany
| | - Wibke Singer
- University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | - Lukas Rüttiger
- University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | - Marlies Knipper
- University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
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Kiefer L, Koch L, Merdan-Desik M, Gaese BH, Nowotny M. Comparing the electrophysiological effects of traumatic noise exposure between rodents. J Neurophysiol 2022; 127:452-462. [PMID: 35020518 DOI: 10.1152/jn.00081.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Noise-induced hearing deficits are important health problems in the industrialized world. As the underlying physiological dysfunctions are not well understood, research in suitable animal models is urgently needed. Three rodent species (Mongolian gerbil, rat and mouse) were studied to compare the temporal dynamics of noise-induced hearing loss after identical procedures of noise exposure. Auditory brainstem responses (ABRs) were measured before, during and up to eight weeks after noise exposure for threshold determination and ABR waveform analysis. Trauma induction with stepwise increasing sound pressure level was interrupted by five interspersed ABR measurements. Comparing short- and long-term dynamics underlying the following noise-induced hearing loss revealed diverging time courses between the three species. Hearing loss occurred early on during noise exposure in all three rodent species at or above trauma frequency. Initial noise level (105 dB SPL) was most effective in rats while the delayed level-increase to 115 dB SPL affected mice much stronger. Induced temporary threshold shifts in rats and mice were larger in animals with lower pre-trauma ABR thresholds. The increase in activity (gain) along the auditory pathway was derived by comparing the amplitudes of short- and long-latency ABR waveform components. Directly after trauma, significant effects were found for rats (decreasing gain) and mice (increasing gain) while gerbils revealed high individual variability in gain changes. Taken together, our comparative study revealed pronounced species-specific differences in the development of noise-induced hearing loss and the related processing along the auditory pathway.
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Affiliation(s)
- Lenneke Kiefer
- Institute of Cell Biology and Neuroscience, Goethe University, Frankfurt am Main, Germany
| | - Lisa Koch
- Institute of Cell Biology and Neuroscience, Goethe University, Frankfurt am Main, Germany
| | - Melisa Merdan-Desik
- Institute of Cell Biology and Neuroscience, Goethe University, Frankfurt am Main, Germany.,Institute of Zoology and Evolutionary Research, Friedrich-Schiller-University, Jena, Germany
| | - Bernhard H Gaese
- Institute of Cell Biology and Neuroscience, Goethe University, Frankfurt am Main, Germany
| | - Manuela Nowotny
- Institute of Cell Biology and Neuroscience, Goethe University, Frankfurt am Main, Germany.,Institute of Zoology and Evolutionary Research, Friedrich-Schiller-University, Jena, Germany
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9
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Knipper M, Singer W, Schwabe K, Hagberg GE, Li Hegner Y, Rüttiger L, Braun C, Land R. Disturbed Balance of Inhibitory Signaling Links Hearing Loss and Cognition. Front Neural Circuits 2022; 15:785603. [PMID: 35069123 PMCID: PMC8770933 DOI: 10.3389/fncir.2021.785603] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 12/08/2021] [Indexed: 12/19/2022] Open
Abstract
Neuronal hyperexcitability in the central auditory pathway linked to reduced inhibitory activity is associated with numerous forms of hearing loss, including noise damage, age-dependent hearing loss, and deafness, as well as tinnitus or auditory processing deficits in autism spectrum disorder (ASD). In most cases, the reduced central inhibitory activity and the accompanying hyperexcitability are interpreted as an active compensatory response to the absence of synaptic activity, linked to increased central neural gain control (increased output activity relative to reduced input). We here suggest that hyperexcitability also could be related to an immaturity or impairment of tonic inhibitory strength that typically develops in an activity-dependent process in the ascending auditory pathway with auditory experience. In these cases, high-SR auditory nerve fibers, which are critical for the shortest latencies and lowest sound thresholds, may have either not matured (possibly in congenital deafness or autism) or are dysfunctional (possibly after sudden, stressful auditory trauma or age-dependent hearing loss linked with cognitive decline). Fast auditory processing deficits can occur despite maintained basal hearing. In that case, tonic inhibitory strength is reduced in ascending auditory nuclei, and fast inhibitory parvalbumin positive interneuron (PV-IN) dendrites are diminished in auditory and frontal brain regions. This leads to deficits in central neural gain control linked to hippocampal LTP/LTD deficiencies, cognitive deficits, and unbalanced extra-hypothalamic stress control. Under these conditions, a diminished inhibitory strength may weaken local neuronal coupling to homeostatic vascular responses required for the metabolic support of auditory adjustment processes. We emphasize the need to distinguish these two states of excitatory/inhibitory imbalance in hearing disorders: (i) Under conditions of preserved fast auditory processing and sustained tonic inhibitory strength, an excitatory/inhibitory imbalance following auditory deprivation can maintain precise hearing through a memory linked, transient disinhibition that leads to enhanced spiking fidelity (central neural gain⇑) (ii) Under conditions of critically diminished fast auditory processing and reduced tonic inhibitory strength, hyperexcitability can be part of an increased synchronization over a broader frequency range, linked to reduced spiking reliability (central neural gain⇓). This latter stage mutually reinforces diminished metabolic support for auditory adjustment processes, increasing the risks for canonical dementia syndromes.
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Affiliation(s)
- Marlies Knipper
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
- *Correspondence: Marlies Knipper,
| | - Wibke Singer
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Kerstin Schwabe
- Experimental Neurosurgery, Department of Neurosurgery, Hannover Medical School, Hanover, Germany
| | - Gisela E. Hagberg
- Department of Biomedical Magnetic Resonance, University Hospital Tübingen (UKT), Tübingen, Germany
- High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Yiwen Li Hegner
- MEG Center, University of Tübingen, Tübingen, Germany
- Center of Neurology, Hertie-Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Lukas Rüttiger
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Christoph Braun
- MEG Center, University of Tübingen, Tübingen, Germany
- Center of Neurology, Hertie-Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Rüdiger Land
- Department of Experimental Otology, Institute for Audioneurotechnology, Hannover Medical School, Hanover, Germany
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10
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Liu Z, Fei B, Xie L, Liu J, Chen X, Zhu W, Lv L, Ma W, Gao Z, Hou J, She W. Glucocorticoids protect HEI-OC1 cells from tunicamycin-induced cell damage via inhibiting endoplasmic reticulum stress. Open Life Sci 2021; 16:695-702. [PMID: 34250248 PMCID: PMC8253451 DOI: 10.1515/biol-2021-0057] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 02/20/2021] [Accepted: 03/24/2021] [Indexed: 11/18/2022] Open
Abstract
Background To analyze mechanisms of action of glucocorticoid treatment for endoplasmic reticulum stress (ERS) in sensorineural hearing loss (SNHL), we aimed to evaluate the expression and activation status of the protein kinase RNA-like ER kinase (PERK)–C/EBP homologous protein (CHOP) pathway, which is the major pathway in the ERS. Methods In the present study, we established an in vitro ERS model using tunicamycin-treated hair-cell-like HEI-OC1 cells. The effect of dexamethasone on proliferation inhibition, apoptosis, and ATF4–CHOP pathway in HEI-OC1 cells was examined by CCK-8 assay, flow cytometry, western blotting, and reverse transcription PCR, respectively. Results In HEI-OC1 cells, dexamethasone was shown to significantly reduce the tunicamycin-induced expression of ATF4 and CHOP in the context of sustained viability and proliferation, a therapeutic effect that was reversible by co-treatment with a glucocorticoid antagonist. Conclusion Dexamethasone can protect hair-cell-like HEI-OC1 cells from ERS damage, which may be one of the mechanisms of action for GCs in SNHL treatment.
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Affiliation(s)
- Zhibiao Liu
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, 321 Zhongshan Road, Nanjing 210008, China
- Department of Otorhinolaryngology-Head and Neck Surgery, The Affiliated Huaian No. 1 People’s Hospital of Nanjing Medical University, Huaian, Nanjing, China
| | - Bing Fei
- Department of Otolaryngology-Head and Neck Surgery, Affiliated Huai’an Hospital of Xuzhou Medical University, 62 South Huaihai Road, Huai’an 223002, China
| | - Lisheng Xie
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, 321 Zhongshan Road, Nanjing 210008, China
| | - Jin Liu
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210000, China
| | - Xiaorui Chen
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210000, China
| | - Wenyan Zhu
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, 321 Zhongshan Road, Nanjing 210008, China
- Department of Otorhinolaryngology-Head and Neck Surgery, The Affiliated Huaian No. 1 People’s Hospital of Nanjing Medical University, Huaian, Nanjing, China
| | - Lingyun Lv
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, 321 Zhongshan Road, Nanjing 210008, China
- Department of Otorhinolaryngology-Head and Neck Surgery, The Affiliated Huaian No. 1 People’s Hospital of Nanjing Medical University, Huaian, Nanjing, China
| | - Wei Ma
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, 321 Zhongshan Road, Nanjing 210008, China
| | - Ziwen Gao
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, 321 Zhongshan Road, Nanjing 210008, China
| | - Jie Hou
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, 321 Zhongshan Road, Nanjing 210008, China
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Jiangsu Provincial Key Medical Discipline, Nanjing, China
| | - Wandong She
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, 321 Zhongshan Road, Nanjing 210008, China
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Jiangsu Provincial Key Medical Discipline, Nanjing, China
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210000, China
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11
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Obleser J, Kreitewolf J, Vielhauer R, Lindner F, David C, Oster H, Tune S. Circadian fluctuations in glucocorticoid level predict perceptual discrimination sensitivity. iScience 2021; 24:102345. [PMID: 33870139 PMCID: PMC8047178 DOI: 10.1016/j.isci.2021.102345] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 03/01/2021] [Accepted: 03/18/2021] [Indexed: 01/17/2023] Open
Abstract
Slow neurobiological rhythms, such as the circadian secretion of glucocorticoid (GC) hormones, modulate a variety of body functions. Whether and how endocrine fluctuations also exert an influence on perceptual abilities is largely uncharted. Here, we show that phasic increases in GC availability prove beneficial to auditory discrimination. In an age-varying sample of N = 68 healthy human participants, we characterize the covariation of saliva cortisol with perceptual sensitivity in an auditory pitch discrimination task at five time points across the sleep-wake cycle. First, momentary saliva cortisol levels were captured well by the time relative to wake-up and overall sleep duration. Second, within individuals, higher cortisol levels just prior to behavioral testing predicted better pitch discrimination ability, expressed as a steepened psychometric curve. This effect of GCs held under a set of statistical controls. Our results pave the way for more in-depth studies on neuroendocrinological determinants of sensory encoding and perception.
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Affiliation(s)
- Jonas Obleser
- Department of Psychology, University of Lübeck, 23562 Lübeck, Germany
- Center for Brain, Behavior, and Metabolism, University of Lübeck, 23562 Lübeck, Germany
| | - Jens Kreitewolf
- Department of Psychology, University of Lübeck, 23562 Lübeck, Germany
- Department of Psychology, McGill University, Montréal, QC, Canada
- Department of Mathematics and Statistics, McGill University, Montréal, QC, Canada
| | - Ricarda Vielhauer
- Department of Psychology, University of Lübeck, 23562 Lübeck, Germany
| | - Fanny Lindner
- Department of Psychology, University of Lübeck, 23562 Lübeck, Germany
| | - Carolin David
- Department of Psychology, University of Lübeck, 23562 Lübeck, Germany
| | - Henrik Oster
- Institute of Neurobiology, University of Lübeck, 23562 Lübeck, Germany
- Center for Brain, Behavior, and Metabolism, University of Lübeck, 23562 Lübeck, Germany
| | - Sarah Tune
- Department of Psychology, University of Lübeck, 23562 Lübeck, Germany
- Center for Brain, Behavior, and Metabolism, University of Lübeck, 23562 Lübeck, Germany
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12
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Wang Q, Wang X, Yang L, Han K, Huang Z, Wu H. Sex differences in noise-induced hearing loss: a cross-sectional study in China. Biol Sex Differ 2021; 12:24. [PMID: 33676563 PMCID: PMC7937304 DOI: 10.1186/s13293-021-00369-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 02/23/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Significant sex differences exist in hearing physiology, while few human studies have investigated sex differences in noise-induced hearing loss (NIHL), and the sex bias in previous studies resulted in inadequate female data. The study aims to investigate sex differences in the characteristics of NIHL to provide insight into sex-specific risk factors, prevention strategies and treatment for NIHL. METHODS This cross-sectional study included 2280 industrial noise-exposed shipyard workers (1140 males and 1140 females matched for age, job and employment length) in China. Individual noise exposure levels were measured to calculate the cumulative noise exposure (CNE), and an audiometric test was performed by an experienced technician in a soundproof booth. Sex differences in and influencing factors of low-frequency (LFHL) and high-frequency hearing loss (HFHL) were analyzed using logistic regression models stratified by age and CNE. RESULTS At comparable noise exposure levels and ages, the prevalence of HFHL was significantly higher in males (34.4%) than in females (13.8%), and males had a higher prevalence of HFHL (OR = 4.19, 95% CI 3.18 to 5.52) after adjusting for age, CNE, and other covariates. Sex differences were constant and highly remarkable among subjects aged 30 to 40 years and those with a CNE of 80 to 95 dB(A). Alcohol consumption might be a risk factor for HFHL in females (OR = 3.12, 95% CI 1.10 to 8.89). CONCLUSIONS This study indicates significant sex differences in NIHL. Males are at higher risk of HFHL than females despite equivalent noise exposure and age. The risk factors for NIHL might be different in males and females.
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Affiliation(s)
- Qixuan Wang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 639 ZhiZaoJu Road, HuangPu District, Shanghai, 200011, People's Republic of China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China.,Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, 200011, People's Republic of China
| | - Xueling Wang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 639 ZhiZaoJu Road, HuangPu District, Shanghai, 200011, People's Republic of China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China.,Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, 200011, People's Republic of China.,Biobank, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China
| | - Lu Yang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 639 ZhiZaoJu Road, HuangPu District, Shanghai, 200011, People's Republic of China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China.,Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, 200011, People's Republic of China
| | - Kun Han
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 639 ZhiZaoJu Road, HuangPu District, Shanghai, 200011, People's Republic of China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China.,Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, 200011, People's Republic of China
| | - Zhiwu Huang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 639 ZhiZaoJu Road, HuangPu District, Shanghai, 200011, People's Republic of China. .,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China. .,Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, 200011, People's Republic of China.
| | - Hao Wu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 639 ZhiZaoJu Road, HuangPu District, Shanghai, 200011, People's Republic of China. .,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China. .,Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, 200011, People's Republic of China.
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13
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The Neural Bases of Tinnitus: Lessons from Deafness and Cochlear Implants. J Neurosci 2021; 40:7190-7202. [PMID: 32938634 DOI: 10.1523/jneurosci.1314-19.2020] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 08/05/2020] [Accepted: 08/08/2020] [Indexed: 02/06/2023] Open
Abstract
Subjective tinnitus is the conscious perception of sound in the absence of any acoustic source. The literature suggests various tinnitus mechanisms, most of which invoke changes in spontaneous firing rates of central auditory neurons resulting from modification of neural gain. Here, we present an alternative model based on evidence that tinnitus is: (1) rare in people who are congenitally deaf, (2) common in people with acquired deafness, and (3) potentially suppressed by active cochlear implants used for hearing restoration. We propose that tinnitus can only develop after fast auditory fiber activity has stimulated the synapse formation between fast-spiking parvalbumin positive (PV+) interneurons and projecting neurons in the ascending auditory path and coactivated frontostriatal networks after hearing onset. Thereafter, fast auditory fiber activity promotes feedforward and feedback inhibition mediated by PV+ interneuron activity in auditory-specific circuits. This inhibitory network enables enhanced stimulus resolution, attention-driven contrast improvement, and augmentation of auditory responses in central auditory pathways (neural gain) after damage of slow auditory fibers. When fast auditory fiber activity is lost, tonic PV+ interneuron activity is diminished, resulting in the prolonged response latencies, sudden hyperexcitability, enhanced cortical synchrony, elevated spontaneous γ oscillations, and impaired attention/stress-control that have been described in previous tinnitus models. Moreover, because fast processing is gained through sensory experience, tinnitus would not exist in congenital deafness. Electrical cochlear stimulation may have the potential to reestablish tonic inhibitory networks and thus suppress tinnitus. The proposed framework unites many ideas of tinnitus pathophysiology and may catalyze cooperative efforts to develop tinnitus therapies.
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14
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Varela-Nieto I, Murillo-Cuesta S, Calvino M, Cediel R, Lassaletta L. Drug development for noise-induced hearing loss. Expert Opin Drug Discov 2020; 15:1457-1471. [PMID: 32838572 DOI: 10.1080/17460441.2020.1806232] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Excessive exposure to noise is a common occurrence that contributes to approximately 50% of the non-genetic hearing loss cases. Researchers need to develop standardized preclinical models and identify molecular targets to effectively develop prevention and curative therapies. AREAS COVERED In this review, the authors discuss the many facets of human noise-induced pathology, and the primary experimental models for studying the basic mechanisms of noise-induced damage, making connections and inferences among basic science studies, preclinical proofs of concept and clinical trials. EXPERT OPINION Whilst experimental research in animal models has helped to unravel the mechanisms of noise-induced hearing loss, there are often methodological variations and conflicting results between animal and human studies which make it difficult to integrate data and translate basic outcomes to clinical practice. Standardization of exposure paradigms and application of -omic technologies will contribute to improving the effectiveness of transferring newly gained knowledge to clinical practice.
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Affiliation(s)
- Isabel Varela-Nieto
- Neurobiology of Hearing Research Group, Endocrine and Nervous System Pathophysiology Department, Institute for Biomedical Research "Alberto Sols" CSIC-UAM , Madrid, Spain.,Institute for Biomedical Research "Alberto Sols" CSIC-UAM , Madrid, Spain.,Oto-Neurosurgery Research Group, Cancer and Human Molecular Genetics Department, IdiPAZ Research Institute , Madrid, Spain
| | - Silvia Murillo-Cuesta
- Neurobiology of Hearing Research Group, Endocrine and Nervous System Pathophysiology Department, Institute for Biomedical Research "Alberto Sols" CSIC-UAM , Madrid, Spain.,Institute for Biomedical Research "Alberto Sols" CSIC-UAM , Madrid, Spain.,Oto-Neurosurgery Research Group, Cancer and Human Molecular Genetics Department, IdiPAZ Research Institute , Madrid, Spain
| | - Miryam Calvino
- Institute for Biomedical Research "Alberto Sols" CSIC-UAM , Madrid, Spain.,Oto-Neurosurgery Research Group, Cancer and Human Molecular Genetics Department, IdiPAZ Research Institute , Madrid, Spain.,Department of Otorhinolaryngology, La Paz University Hospital , Madrid, Spain
| | - Rafael Cediel
- Neurobiology of Hearing Research Group, Endocrine and Nervous System Pathophysiology Department, Institute for Biomedical Research "Alberto Sols" CSIC-UAM , Madrid, Spain.,Institute for Biomedical Research "Alberto Sols" CSIC-UAM , Madrid, Spain.,Oto-Neurosurgery Research Group, Cancer and Human Molecular Genetics Department, IdiPAZ Research Institute , Madrid, Spain.,Department of Animal Medicine and Surgery, Complutense University of Madrid , Madrid, Spain
| | - Luis Lassaletta
- Institute for Biomedical Research "Alberto Sols" CSIC-UAM , Madrid, Spain.,Oto-Neurosurgery Research Group, Cancer and Human Molecular Genetics Department, IdiPAZ Research Institute , Madrid, Spain.,Department of Otorhinolaryngology, La Paz University Hospital , Madrid, Spain
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15
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Peter MN, Paasche G, Reich U, Lenarz T, Warnecke A. Differential Effects of Low- and High-Dose Dexamethasone on Electrically Induced Damage of the Cultured Organ of Corti. Neurotox Res 2020; 38:487-497. [PMID: 32495312 PMCID: PMC7334252 DOI: 10.1007/s12640-020-00228-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 05/02/2020] [Accepted: 05/19/2020] [Indexed: 12/29/2022]
Abstract
An increased number of patients with residual hearing are undergoing cochlear implantation. A subset of these experience delayed hearing loss post-implantation, and the aetiology of this loss is not well understood. Our previous studies suggest that electrical stimulation can induce damage to hair cells in organ of Corti (OC) organotypic cultures. Dexamethasone has the potential to protect residual hearing due to its multiple effects on cells and tissue (e.g., anti-inflammatory, free radical scavenger). We therefore hypothesized that dexamethasone treatment could prevent electrical stimulation induced changes in the OC. Organ of Corti explants from neonatal rats (P2–4) were cultured for 24 h with two different concentrations of dexamethasone. Thereafter, OC were subjected to a charge-balanced biphasic pulsed electrical stimulation (0.44–2 mA) for a further 24 h. Unstimulated dexamethasone-treated OC served as controls. Outcome analysis included immunohistochemical labelling of ribbon synapses, histochemical analysis of free reactive oxygen species and morphological analysis of stereocilia bundles. Overall, the protective effects of dexamethasone on electrically induced damage in cochlear explants were moderate. High-dose dexamethasone protected bundle integrity at higher current levels. Low-dose dexamethasone tended to increase ribbon density in the apical region.
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Affiliation(s)
- Marvin N Peter
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Gerrit Paasche
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.,Cluster of Excellence "Hearing4all" of the German Research Foundation, Hannover, Germany
| | - Uta Reich
- Department of Otorhinolaryngology, Head and Neck Surgery, Berlin Institute of Health, Charité-Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Thomas Lenarz
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.,Cluster of Excellence "Hearing4all" of the German Research Foundation, Hannover, Germany
| | - Athanasia Warnecke
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany. .,Cluster of Excellence "Hearing4all" of the German Research Foundation, Hannover, Germany.
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16
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Marchetta P, Möhrle D, Eckert P, Reimann K, Wolter S, Tolone A, Lang I, Wolters M, Feil R, Engel J, Paquet-Durand F, Kuhn M, Knipper M, Rüttiger L. Guanylyl Cyclase A/cGMP Signaling Slows Hidden, Age- and Acoustic Trauma-Induced Hearing Loss. Front Aging Neurosci 2020; 12:83. [PMID: 32327991 PMCID: PMC7160671 DOI: 10.3389/fnagi.2020.00083] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 03/10/2020] [Indexed: 12/24/2022] Open
Abstract
In the inner ear, cyclic guanosine monophosphate (cGMP) signaling has been described as facilitating otoprotection, which was previously observed through elevated cGMP levels achieved by phosphodiesterase 5 inhibition. However, to date, the upstream guanylyl cyclase (GC) subtype eliciting cGMP production is unknown. Here, we show that mice with a genetic disruption of the gene encoding the cGMP generator GC-A, the receptor for atrial and B-type natriuretic peptides, display a greater vulnerability of hair cells to hidden hearing loss and noise- and age-dependent hearing loss. This vulnerability was associated with GC-A expression in spiral ganglia and outer hair cells (OHCs) but not in inner hair cells (IHCs). GC-A knockout mice exhibited elevated hearing thresholds, most pronounced for the detection of high-frequency tones. Deficits in OHC input–output functions in high-frequency regions were already present in young GC-A-deficient mice, with no signs of an accelerated progression of age-related hearing loss or higher vulnerability to acoustic trauma. OHCs in these frequency regions in young GC-A knockout mice exhibited diminished levels of KCNQ4 expression, which is the dominant K+ channel in OHCs, and decreased activation of poly (ADP-ribose) polymerase-1, an enzyme involved in DNA repair. Further, GC-A knockout mice had IHC synapse impairments and reduced amplitudes of auditory brainstem responses that progressed with age and with acoustic trauma, in contrast to OHCs, when compared to GC-A wild-type littermates. We conclude that GC-A/cGMP-dependent signaling pathways have otoprotective functions and GC-A gene disruption differentially contributes to hair-cell damage in a healthy, aged, or injured system. Thus, augmentation of natriuretic peptide GC-A signaling likely has potential to overcome hidden and noise-induced hearing loss, as well as presbycusis.
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Affiliation(s)
- Philine Marchetta
- Molecular Physiology of Hearing, Tübingen Hearing Research Centre, Department of Otolaryngology, University of Tübingen, Tübingen, Germany
| | - Dorit Möhrle
- Molecular Physiology of Hearing, Tübingen Hearing Research Centre, Department of Otolaryngology, University of Tübingen, Tübingen, Germany.,Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada
| | - Philipp Eckert
- Molecular Physiology of Hearing, Tübingen Hearing Research Centre, Department of Otolaryngology, University of Tübingen, Tübingen, Germany
| | - Katrin Reimann
- Molecular Physiology of Hearing, Tübingen Hearing Research Centre, Department of Otolaryngology, University of Tübingen, Tübingen, Germany
| | - Steffen Wolter
- Molecular Physiology of Hearing, Tübingen Hearing Research Centre, Department of Otolaryngology, University of Tübingen, Tübingen, Germany
| | - Arianna Tolone
- Cell Death Mechanisms Group, Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Isabelle Lang
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine, Hearing Research, Saarland University, Homburg, Germany
| | - Markus Wolters
- Signal Transduction and Transgenic Models, Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Robert Feil
- Signal Transduction and Transgenic Models, Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Jutta Engel
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine, Hearing Research, Saarland University, Homburg, Germany
| | - François Paquet-Durand
- Cell Death Mechanisms Group, Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Michaela Kuhn
- Institute of Physiology, University of Würzburg, Würzburg, Germany
| | - Marlies Knipper
- Molecular Physiology of Hearing, Tübingen Hearing Research Centre, Department of Otolaryngology, University of Tübingen, Tübingen, Germany
| | - Lukas Rüttiger
- Molecular Physiology of Hearing, Tübingen Hearing Research Centre, Department of Otolaryngology, University of Tübingen, Tübingen, Germany
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17
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Li P, Bing D, Wang S, Chen J, Du Z, Sun Y, Qi F, Zhang Y, Chu H. Sleep Deprivation Modifies Noise-Induced Cochlear Injury Related to the Stress Hormone and Autophagy in Female Mice. Front Neurosci 2019; 13:1297. [PMID: 31849600 PMCID: PMC6896935 DOI: 10.3389/fnins.2019.01297] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 11/18/2019] [Indexed: 12/20/2022] Open
Abstract
A lack of sleep is linked with a range of inner ear diseases, including hearing loss and tinnitus. Here, we used a mouse model to investigate the effects of sleep deprivation (SD) on noise vulnerability, and explored the mechanisms that might be involved in vitro, focusing particularly corticosterone levels and autophagic flux in cells. Female BALB/c mice were divided into six groups [control, acoustic trauma (AT)-alone, 1 day (d) SD-alone, 1d SD pre-AT, 5d SD-alone, and 5d SD pre-AT]. Cochlear damage was then assessed by analyzing auditory brainstem response (ABR), and by counting outer hair cells (OHCs) and the synaptic ribbons of inner hair cells (IHCs). In addition, we measured levels of serum corticosterone and autophagy protein expression in the basilar membranes by ELISA kits, and western blotting, respectively. We found that SD-alone temporarily elevated ABR wave I amplitude, but had no permanent effect on hearing level or IHC ribbon numbers. Combined with AT, the number of synaptic ribbons in the 1d SD pre-AT group was significantly higher than that in the AT-alone group, whereas the 5d SD pre-AT group showed more severe synaptopathy, and a greater loss of OHCs after 2 weeks than the other experimental groups exposed to noise. Correspondingly, the levels of corticosterone in the AT-alone group were higher than those of the 1d SD pre-AT group, but lower than those of the 5d SD pre-AT group. The 1d SD pre-AT group showed a marked elevation in the expression of microtubule-associated protein 1 light chain 3B (LC3B), whereas the AT-alone group exhibited only a mild increase. In contrast, the levels of LC3B did not change in the 5d SD pre-AT group. Experiments with HEI-OC-1 cells and cochlear basilar membrane cultures showed that high-concentrations of dexamethasone, and the inhibition of autophagy, aggravated cellular apoptosis induced by oxidative stress. In conclusion, noise-induced synaptopathy and hair cell loss can be mitigated by preceding 1d SD, but will be aggravated by preceding 5d SD. These findings may be attributable to corticosterone levels and the extent of autophagy.
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Affiliation(s)
- Pengjun Li
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Dan Bing
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Sumei Wang
- Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jin Chen
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhihui Du
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yanbo Sun
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Fan Qi
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yingmiao Zhang
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, China
| | - Hanqi Chu
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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18
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Knipper M, Hofmeier B, Singer W, Wolpert S, Klose U, Rüttiger L. [Differentiating cochlear synaptopathies into different hearing disorders]. HNO 2019; 67:406-416. [PMID: 30963221 DOI: 10.1007/s00106-019-0660-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Due to demographic change and altered recreational behavior, a rapid increase in hearing deficits is expected in the next 20-30 years. Consequently, the risk of age-related loss of speech discrimination, tinnitus, hyperacusis, or-as recently shown-dementia, will also increase. There are increasing indications that the loss of specific hearing fibers in humans and animals is involved in various hearing disorders. This fiber loss can be caused by cochlear synaptopathy or deafferentation and does not necessarily lead to clinically measurable threshold changes. Animal experiments have shown that reduced auditory nerve activity due to acoustic trauma or aging can be centrally compensated by disproportionately elevated and faster auditory brainstem responses (ABR). The analysis of the suprathreshold amplitudes of auditory evoked brain stem potentials and their latency in combination with non-invasive imaging techniques such as magnetic resonance imaging can help to identify the central compensatory ability of subjects and to assign defined hearing deficits.
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Affiliation(s)
- M Knipper
- Universitätsklinik für Hals-Nasen-Ohren-Heilkunde, Plastische Operationen, Sektion Molekulare Hörphysiologie, Hörforschungszentrum Tübingen (THRC), Elfriede-Aulhorn-Straße 5, 72076, Tübingen, Deutschland.
| | - B Hofmeier
- Universitätsklinik für Hals-Nasen-Ohren-Heilkunde, Plastische Operationen, Sektion Molekulare Hörphysiologie, Hörforschungszentrum Tübingen (THRC), Elfriede-Aulhorn-Straße 5, 72076, Tübingen, Deutschland
| | - W Singer
- Universitätsklinik für Hals-Nasen-Ohren-Heilkunde, Plastische Operationen, Sektion Molekulare Hörphysiologie, Hörforschungszentrum Tübingen (THRC), Elfriede-Aulhorn-Straße 5, 72076, Tübingen, Deutschland
| | - S Wolpert
- Universitätsklinik für Hals-Nasen-Ohren-Heilkunde, Plastische Operationen, Sektion Molekulare Hörphysiologie, Hörforschungszentrum Tübingen (THRC), Elfriede-Aulhorn-Straße 5, 72076, Tübingen, Deutschland
| | - U Klose
- MR-Forschung, Abteilung für Diagnostische und Interventionelle Neuroradiologie, Universitätsklinikum Tübingen, Tübingen, Deutschland
| | - L Rüttiger
- Universitätsklinik für Hals-Nasen-Ohren-Heilkunde, Plastische Operationen, Sektion Molekulare Hörphysiologie, Hörforschungszentrum Tübingen (THRC), Elfriede-Aulhorn-Straße 5, 72076, Tübingen, Deutschland
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19
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Warnecke A, Prenzler NK, Schmitt H, Daemen K, Keil J, Dursin M, Lenarz T, Falk CS. Defining the Inflammatory Microenvironment in the Human Cochlea by Perilymph Analysis: Toward Liquid Biopsy of the Cochlea. Front Neurol 2019; 10:665. [PMID: 31293504 PMCID: PMC6603180 DOI: 10.3389/fneur.2019.00665] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Accepted: 06/06/2019] [Indexed: 12/20/2022] Open
Abstract
The molecular pathomechanisms in the majority of patients suffering from acute or progressive sensorineural hearing loss cannot be determined yet. The size and the complex architecture of the cochlea make biopsy and in-depth histological analyses impossible without severe damage of the organ. Thus, histopathology correlated to inner disease is only possible after death. The establishment of a technique for perilymph sampling during cochlear implantation may enable a liquid biopsy and characterization of the cochlear microenvironment. Inflammatory processes may not only participate in disease onset and progression in the inner ear, but may also control performance of the implant. However, little is known about cytokines and chemokines in the human inner ear as predictive markers for cochlear implant performance. First attempts to use multiplex protein arrays for inflammatory markers were successful for the identification of cytokines, chemokines, and endothelial markers present in the human perilymph. Moreover, unsupervised cluster and principal component analyses were used to group patients by lead cytokines and to correlate certain proteins to clinical data. Endothelial and epithelial factors were detected at higher concentrations than typical pro-inflammatory cytokines such as TNF-a or IL-6. Significant differences in VEGF family members have been observed comparing patients with deafness to patients with residual hearing with significantly reduced VEGF-D levels in patients with deafness. In addition, there is a trend toward higher IGFBP-1 levels in these patients. Hence, endothelial and epithelial factors in combination with cytokines may present robust biomarker candidates and will be investigated in future studies in more detail. Thus, multiplex protein arrays are feasible in very small perilymph samples allowing a qualitative and quantitative analysis of inflammatory markers. More results are required to advance this method for elucidating the development and course of specific inner ear diseases or for perioperative characterization of cochlear implant patients.
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Affiliation(s)
- Athanasia Warnecke
- Department of Otolaryngology, Hannover Medical School, Hanover, Germany.,Cluster of Excellence of the German Research Foundation (DFG; "Deutsche Forschungsgemeinschaft") "Hearing4all", Oldenburg, Germany
| | - Nils K Prenzler
- Department of Otolaryngology, Hannover Medical School, Hanover, Germany
| | - Heike Schmitt
- Department of Otolaryngology, Hannover Medical School, Hanover, Germany.,Cluster of Excellence of the German Research Foundation (DFG; "Deutsche Forschungsgemeinschaft") "Hearing4all", Oldenburg, Germany
| | - Kerstin Daemen
- Hannover Medical School, Institute of Transplant Immunology, Hanover, Germany
| | - Jana Keil
- Hannover Medical School, Institute of Transplant Immunology, Hanover, Germany
| | - Martin Dursin
- Department of Otolaryngology, Hannover Medical School, Hanover, Germany
| | - Thomas Lenarz
- Department of Otolaryngology, Hannover Medical School, Hanover, Germany.,Cluster of Excellence of the German Research Foundation (DFG; "Deutsche Forschungsgemeinschaft") "Hearing4all", Oldenburg, Germany
| | - Christine S Falk
- Hannover Medical School, Institute of Transplant Immunology, Hanover, Germany
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20
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Bramhall N, Beach EF, Epp B, Le Prell CG, Lopez-Poveda EA, Plack CJ, Schaette R, Verhulst S, Canlon B. The search for noise-induced cochlear synaptopathy in humans: Mission impossible? Hear Res 2019; 377:88-103. [DOI: 10.1016/j.heares.2019.02.016] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 02/25/2019] [Accepted: 02/28/2019] [Indexed: 10/27/2022]
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21
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Hayes SH, Manohar S, Majumdar A, Allman BL, Salvi R. Noise-induced hearing loss alters hippocampal glucocorticoid receptor expression in rats. Hear Res 2019; 379:43-51. [PMID: 31071644 DOI: 10.1016/j.heares.2019.04.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 03/25/2019] [Accepted: 04/24/2019] [Indexed: 12/11/2022]
Abstract
Although the effects of intense noise exposure on the peripheral and central auditory pathway have been well characterized, its effects on non-classical auditory structures in the brain, such as the hippocampus, are less well understood. Previously, we demonstrated that noise-induced hearing loss causes a significant long-term reduction in hippocampal neurogenesis and cell proliferation. Given the known suppressive effects of stress hormones on neurogenesis, the goal of the present study was to determine if activation of the stress response is an underlying mechanism for the long-term reduction in hippocampal neurogenesis observed following noise trauma. To accomplish this, we monitored basal and reactive blood plasma levels of the stress hormone corticosterone in rats for ten weeks following acoustic trauma, and quantified changes in hippocampal glucocorticoid and mineralocorticoid receptors. Our results indicate that long-term auditory deprivation does not cause a persistent increase in basal or reactive stress hormone levels in the weeks following noise exposure. Instead, we observed a greater decline in reactive corticosterone release in noise-exposed rats between the first and tenth week of sampling compared to control rats. We also observed a significant increase in hippocampal glucocorticoid receptor expression which may cause greater hippocampal sensitivity to circulating glucocorticoid levels and result in glucocorticoid-induced suppression of neurogenesis, as well as increased feedback inhibition on the HPA axis. No change in mineralocorticoid receptor expression was observed between control and noise exposed rats. These results highlight the adverse effect of intense noise exposure and auditory deprivation on the hippocampus.
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Affiliation(s)
- Sarah H Hayes
- Center for Hearing and Deafness, The State University of New York at Buffalo, Buffalo, NY, USA; Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario, Ontario, N6A 5C1, Canada.
| | - Senthilvelan Manohar
- Center for Hearing and Deafness, The State University of New York at Buffalo, Buffalo, NY, USA
| | - Antara Majumdar
- Center for Hearing and Deafness, The State University of New York at Buffalo, Buffalo, NY, USA
| | - Brian L Allman
- Center for Hearing and Deafness, The State University of New York at Buffalo, Buffalo, NY, USA; Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario, Ontario, N6A 5C1, Canada
| | - Richard Salvi
- Center for Hearing and Deafness, The State University of New York at Buffalo, Buffalo, NY, USA
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22
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Yamahara K, Asaka N, Kita T, Kishimoto I, Matsunaga M, Yamamoto N, Omori K, Nakagawa T. Insulin-like growth factor 1 promotes cochlear synapse regeneration after excitotoxic trauma in vitro. Hear Res 2019; 374:5-12. [PMID: 30682699 DOI: 10.1016/j.heares.2019.01.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 01/11/2019] [Accepted: 01/14/2019] [Indexed: 10/27/2022]
Abstract
In the context of acquired sensorineural hearing loss (SNHL), cochlear hair cells have long been thought to be among the most vulnerable elements in mammalian cochleae. However, recent studies have indicated that the synaptic connection between inner hair cells (IHC) and spiral ganglion neurons (SGN) can be an important target for the treatment of SNHL. Our previous studies in patients with sudden SNHL demonstrated delayed and gradual hearing recovery following topical application of insulin-like growth factor 1 (IGF-1), suggesting that not only protective but also regenerative mechanisms may account for hearing recovery after treatment with IGF-1. We then hypothesized that IGF-1 has the potential to drive the regeneration of IHC-SGN synapses. To test this hypothesis, we investigated the effects of IGF-1 on IHC-SGN synapses using cochlear explant cultures from postnatal day 2 mice that had been damaged by exposure to the excitatory amino acids N-methyl-d-aspartate and kainate. Cochlear explants that lost IHC-SGN synapses upon exposure to excitatory amino acids were cultured with exogenous IGF-1 for an additional 48 h. We observed increased numbers of IHC-SGN synapses after exogenous IGF-1 application. Pharmacological inhibition of the IGF-1 receptor attenuated the restoration of IHC-SGN synapses by exogenous IGF-1. These findings indicated that IGF-1 induces regeneration of IHC-SGN synapses in cochlear explant cultures from postnatal day 2 mice. Therefore, in a future study we will perform in vivo experiments using adult mice to ascertain the effects of IGF-1 on the regeneration of IHC-SGN synapses.
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Affiliation(s)
- Kohei Yamahara
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan; Department of Otolaryngology, Head and Neck Surgery, Shizuoka City Shizuoka Hospital, Shizuoka, Shizuoka, 420-8630, Japan
| | - Nakarin Asaka
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan; Department of Sensory Medicine, Akita University School of Medicine, Akita, 010-8543, Japan
| | - Tomoko Kita
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Ippei Kishimoto
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Mami Matsunaga
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Norio Yamamoto
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Koichi Omori
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Takayuki Nakagawa
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan.
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23
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Möhrle D, Hofmeier B, Amend M, Wolpert S, Ni K, Bing D, Klose U, Pichler B, Knipper M, Rüttiger L. Enhanced Central Neural Gain Compensates Acoustic Trauma-induced Cochlear Impairment, but Unlikely Correlates with Tinnitus and Hyperacusis. Neuroscience 2018; 407:146-169. [PMID: 30599268 DOI: 10.1016/j.neuroscience.2018.12.038] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 12/18/2018] [Accepted: 12/20/2018] [Indexed: 01/09/2023]
Abstract
For successful future therapeutic strategies for tinnitus and hyperacusis, a subcategorization of both conditions on the basis of differentiated neural correlates would be of invaluable advantage. In the present study, we used our refined operant conditioning animal model to divide equally noise-exposed rats into groups with either tinnitus or hyperacusis, with neither condition, or with both conditions co-occurring simultaneously. Using click stimulus and noise burst-evoked Auditory Brainstem Responses (ABR) and Distortion Product Otoacoustic Emissions, no hearing threshold difference was observed between any of the groups. However, animals with neither tinnitus nor hyperacusis responded to noise trauma with shortened ABR wave I and IV latencies and elevated central neuronal gain (increased ABR wave IV/I amplitude ratio), which was previously assumed in most of the literature to be a neural correlate for tinnitus. In contrast, animals with tinnitus had reduced neural response gain and delayed ABR wave I and IV latencies, while animals with hyperacusis showed none of these changes. Preliminary studies, aimed at establishing comparable non-invasive objective tools for identifying tinnitus in humans and animals, confirmed reduced central gain and delayed response latency in human and animals. Moreover, the first ever resting state functional Magnetic Resonance Imaging (rs-fMRI) analyses comparing humans and rats with and without tinnitus showed reduced rs-fMRI activities in the auditory cortex in both patients and animals with tinnitus. These findings encourage further efforts to establish non-invasive diagnostic tools that can be used in humans and animals alike and give hope for differentiated classification of tinnitus and hyperacusis.
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Affiliation(s)
- Dorit Möhrle
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
| | - Benedikt Hofmeier
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
| | - Mario Amend
- University of Tübingen, Department of Preclinical Imaging and Radiopharmacy, University Hospital Tübingen, Röntgenweg 13, 72076 Tübingen, Germany.
| | - Stephan Wolpert
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
| | - Kun Ni
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany; Shanghai Jiao Tong University, Department of Otolaryngology, Head & Neck Surgery, Shanghai Children's Hospital, Shanghai Luding Road, NO. 355. Putuo District, 200062 Shanghai, China.
| | - Dan Bing
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
| | - Uwe Klose
- University Hospital Tübingen, Department of Diagnostic and Interventional Neuroradiology, Hoppe-Seyler-Str. 3, 72076 Tübingen, Germany.
| | - Bernd Pichler
- University of Tübingen, Department of Preclinical Imaging and Radiopharmacy, University Hospital Tübingen, Röntgenweg 13, 72076 Tübingen, Germany.
| | - Marlies Knipper
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
| | - Lukas Rüttiger
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
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24
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Hofmeier B, Wolpert S, Aldamer ES, Walter M, Thiericke J, Braun C, Zelle D, Rüttiger L, Klose U, Knipper M. Reduced sound-evoked and resting-state BOLD fMRI connectivity in tinnitus. NEUROIMAGE-CLINICAL 2018; 20:637-649. [PMID: 30202725 PMCID: PMC6128096 DOI: 10.1016/j.nicl.2018.08.029] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 08/29/2018] [Accepted: 08/30/2018] [Indexed: 01/02/2023]
Abstract
The exact neurophysiological basis of chronic tinnitus, which affects 10-15% of the population, remains unknown and is controversial at many levels. It is an open question whether phantom sound perception results from increased central neural gain or not, a crucial question for any future therapeutic intervention strategies for tinnitus. We performed a comprehensive study of mild hearing-impaired participants with and without tinnitus, excluding participants with co-occurrences of hyperacusis. A right-hemisphere correlation between tinnitus loudness and auditory perceptual difficulty was observed in the tinnitus group, independent of differences in hearing thresholds. This correlation was linked to reduced and delayed sound-induced suprathreshold auditory brain responses (ABR wave V) in the tinnitus group, suggesting subsided rather than exaggerated central neural responsiveness. When anatomically predefined auditory regions of interest were analysed for altered sound-evoked BOLD fMRI activity, it became evident that subcortical and cortical auditory regions and regions involved in sound detection (posterior insula, hippocampus), responded with reduced BOLD activity in the tinnitus group, emphasizing reduced, rather than increased, central neural gain. Regarding previous findings of evoked BOLD activity being linked to positive connectivities at rest, we additionally analysed r-fcMRI responses in anatomically predefined auditory regions and regions associated with sound detection. A profound reduction in positive interhemispheric connections of homologous auditory brain regions and a decline in the positive connectivities between lower auditory brainstem regions and regions involved in sound detection (hippocampus, posterior insula) were observed in the tinnitus group. The finding went hand-in-hand with the emotional (amygdala, anterior insula) and temporofrontal/stress-regulating regions (prefrontal cortex, inferior frontal gyrus) that were no longer positively connected with auditory cortex regions in the tinnitus group but were instead positively connected to lower-level auditory brainstem regions. Delayed sound processing, reduced sound-evoked BOLD fMRI activity and altered r-fcMRI in the auditory midbrain correlated in the tinnitus group and showed right hemisphere dominance as did tinnitus loudness and perceptual difficulty. The findings suggest that reduced central neural gain in the auditory stream may lead to phantom perception through a failure to energize attentional/stress-regulating networks for contextualization of auditory-specific information. Reduced auditory-specific information flow in tinnitus has until now escaped detection in humans, as low-level auditory brain regions were previously omitted from neuroimaging studies. TRIAL REGISTRATION German Clinical Trials Register DRKS0006332.
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Key Words
- ABR wave
- ABR, auditory brainstem response
- BA, Brodmann area
- BA13A, anterior insula
- BA13P, posterior insula
- BA28, entorhinal cortex
- BB-chirp, broadband chirp
- BERA, brainstem-evoked response audiometry
- CN, cochlear nucleus
- CSF, cerebrospinal fluid
- Cortisol
- DL, dorsolateral
- EFR, envelope-followed responses
- ENT, ear, nose and throat
- FA, flip angle
- FDR, false discovery rate
- FOV, field of view
- FWHM, full width at half maximum
- G-H-S, Goebel-Hiller-Score
- HF-chirp, high-frequency chirp
- HPA, hypothalamic-pituitary-adrenal
- High-SR AF, high-spontaneous firing rates auditory fibers
- IC, inferior colliculus
- L, left
- LF-chirp, low-frequency chirp
- Low-SR AF, low-spontaneous firing rates auditory fibers
- M, medial
- MGB, medial geniculate body
- MNI, Montreal Neurological Institute
- PFC, prefrontal cortex
- PTA, pure tone audiogram
- R, right
- ROI, region of interest
- SD, standard deviation
- SOC, superior olivary complex
- SPL, sound pressure level
- SPM, Statistical Parametric Mapping
- TA, acquisition time
- TE, echo time
- TR, repetition time
- Tinnitus
- VBM, voxel-based morphometry
- fMRI
- r-fcMRI
- rCBF, resting-state cerebral blood flow
- rCBV, resting-state cerebral blood volume
- zFC, z-values functional connectivity
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Affiliation(s)
- Benedikt Hofmeier
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - Stephan Wolpert
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - Ebrahim Saad Aldamer
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - Moritz Walter
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - John Thiericke
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany/HNO Ärzte Praxis Part GmbB, Aschaffenburg, Germany
| | - Christoph Braun
- MEG Center, University Hospital Tübingen, Otfried-Müller-Str. 47, D-72076 Tübingen, Germany
| | - Dennis Zelle
- Section of Physiological Acoustics and Communication, Department of Otolaryngology, Head and Neck Surgery, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - Lukas Rüttiger
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - Uwe Klose
- Department of Diagnostic and Interventional Neuroradiology, University Hospital Tübingen, Hoppe-Seyler-Str. 3, D-73076 Tübingen, Germany.
| | - Marlies Knipper
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany.
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Matt L, Eckert P, Panford-Walsh R, Geisler HS, Bausch AE, Manthey M, Müller NIC, Harasztosi C, Rohbock K, Ruth P, Friauf E, Ott T, Zimmermann U, Rüttiger L, Schimmang T, Knipper M, Singer W. Visualizing BDNF Transcript Usage During Sound-Induced Memory Linked Plasticity. Front Mol Neurosci 2018; 11:260. [PMID: 30127717 PMCID: PMC6089339 DOI: 10.3389/fnmol.2018.00260] [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: 04/18/2018] [Accepted: 07/12/2018] [Indexed: 12/14/2022] Open
Abstract
Activity-dependent BDNF (brain-derived neurotrophic factor) expression is hypothesized to be a cue for the context-specificity of memory formation. So far, activity-dependent BDNF cannot be explicitly monitored independently of basal BDNF levels. We used the BLEV (BDNF-live-exon-visualization) reporter mouse to specifically detect activity-dependent usage of Bdnf exon-IV and -VI promoters through bi-cistronic co-expression of CFP and YFP, respectively. Enriching acoustic stimuli led to improved peripheral and central auditory brainstem responses, increased Schaffer collateral LTP, and enhanced performance in the Morris water maze. Within the brainstem, neuronal activity was increased and accompanied by a trend for higher expression levels of Bdnf exon-IV-CFP and exon-VI-YFP transcripts. In the hippocampus BDNF transcripts were clearly increased parallel to changes in parvalbumin expression and were localized to specific neurons and capillaries. Severe acoustic trauma, in contrast, elevated neither Bdnf transcript levels, nor auditory responses, parvalbumin or LTP. Together, this suggests that critical sensory input is essential for recruitment of activity-dependent auditory-specific BDNF expression that may shape network adaptation.
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Affiliation(s)
- Lucas Matt
- Department of Pharmacology, Institute of Pharmacy, Toxicology, and Clinical Pharmacy, University of Tübingen, Tübingen, Germany
| | - Philipp Eckert
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Rama Panford-Walsh
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Hyun-Soon Geisler
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Anne E Bausch
- Department of Pharmacology, Institute of Pharmacy, Toxicology, and Clinical Pharmacy, University of Tübingen, Tübingen, Germany
| | - Marie Manthey
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Nicolas I C Müller
- Animal Physiology Group, Department of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Csaba Harasztosi
- Section of Physiological Acoustics and Communication, Department of Otolaryngology, Tübingen Hearing Research Center, University of Tübingen, Tübingen, Germany
| | - Karin Rohbock
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Peter Ruth
- Department of Pharmacology, Institute of Pharmacy, Toxicology, and Clinical Pharmacy, University of Tübingen, Tübingen, Germany
| | - Eckhard Friauf
- Animal Physiology Group, Department of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Thomas Ott
- Transgenic Facility Tübingen, University of Tübingen, Tübingen, Germany
| | - Ulrike Zimmermann
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Lukas Rüttiger
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Thomas Schimmang
- Instituto de Biologíay Genética Molecular, Universidad de Valladolid, Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - Marlies Knipper
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Wibke Singer
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
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