Auditory brainstem responses predict behavioral deficits in rats with varying levels of noise-induced hearing loss

Abstract Background Noise-induced hearing loss represents a commonly diagnosed type of hearing disability, severely impacting the quality of life of individuals. The current work is aimed at assessing the effects of DNA methylation on noise-induced hearing loss. Methods Blocking DNA methyltransferase 1 (DNMT1) activity with a selective inhibitor RG108 or silencing DNMT1 with siRNA was used in this study. Auditory brainstem responses were measured at baseline and 2 days after trauma in mice to assess auditory functions. Whole-mount immunofluorescent staining and confocal microcopy of mouse inner ear specimens were performed to analyze noise-induced damage in cochleae and the auditory nerve at 2 days after noise exposure. Results The results showed that noise exposure caused threshold elevation of auditory brainstem responses and cochlear hair cell loss. Whole-mount cochlea staining revealed a reduction in the density of auditory ribbon synapses between inner hair cells and spiral ganglion neurons. Inhibition of DNA methyltransferase activity via a non-nucleoside specific pharmacological inhibitor, RG108, or silencing of DNA methyltransferase-1 with siRNA significantly attenuated ABR threshold elevation, hair cell damage, and the loss of auditory synapses. Conclusions This study suggests that inhibition of DNMT1 ameliorates noise-induced hearing loss and indicates that DNMT1 may be a promising therapeutic target. Graphical abstract

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Effect of Electroacupuncture on Noise-Induced Hearing Loss in Rats

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2021/9114676 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Chia-Hao Chang ◽

Chia-Der Lin ◽

Ching-Liang Hsieh

Keyword(s):

Hearing Loss ◽

Noise Exposure ◽

Histopathological Examination ◽

Spiral Ganglion ◽

Auditory Brainstem ◽

Auditory Threshold ◽

Auditory Brainstem Responses ◽

Control Group ◽

Noise Induced Hearing Loss ◽

Ganglion Neurons

Acupuncture has long been used to relieve some inner ear diseases such as deafness and tinnitus. The present study examined the effect of electroacupuncture (EA) on noise-induced hearing loss (NIHL) in animals. A NIHL rat model was established. Electroacupuncture pretreatment at 2 Hz or posttreatment at the right Zhongzhu (TE3) acupoint was applied for 1 hour. Auditory thresholds were measured using auditory brainstem responses (ABRs), and histopathology of the cochlea was examined. The results indicated that the baseline auditory threshold of ABR was not significantly different between the control (no noise), EA-only (only EA without noise), noise (noise exposure only), pre-EA (pretreating EA then noise), and post-EA (noise exposure then posttreating with EA) groups. Significant auditory threshold shifts were found in the noise, pre-EA, and post-EA groups in the immediate period after noise exposure, whereas auditory recovery was better in the pre-EA and post-EA groups than that in the noise group at the three days, one week (W1), two weeks (W2), three weeks (W3), and four weeks(W4) after noise stimulation. Histopathological examination revealed greater loss of the density of spiral ganglion neurons in the noise group than in the control group at W1 and W2. Although significant loss of spiral ganglion loss happened in pre-EA and post-EA groups, such loss was less than the loss of the noise group, especially W1. These results indicate that either pretreatment or posttreatment with EA may facilitate auditory recovery after NIHL. The detailed mechanism through which EA alleviates NIHL requires further study.

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Comparing the electrophysiological effects of traumatic noise exposure between rodents

Journal of Neurophysiology ◽

10.1152/jn.00081.2021 ◽

2022 ◽

Author(s):

Lenneke Kiefer ◽

Lisa Koch ◽

Melisa Merdan-Desik ◽

Bernhard H. Gaese ◽

Manuela Nowotny

Keyword(s):

Hearing Loss ◽

Noise Exposure ◽

Temporal Dynamics ◽

Auditory Pathway ◽

Auditory Brainstem ◽

Individual Variability ◽

Rodent Species ◽

Waveform Analysis ◽

Auditory Brainstem Responses ◽

Noise Induced Hearing Loss

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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Effects of Presbycusis and Other Types of Hearing Loss on Auditory Brainstem Responses

International Journal of Audiology ◽

10.3109/14992028609042141 ◽

1986 ◽

Vol 15 (4) ◽

pp. 179-185

Author(s):

Ulf Rosenhall ◽

Kai Pedersen ◽

Mats Dotevall

Keyword(s):

Hearing Loss ◽

Auditory Brainstem ◽

Auditory Brainstem Responses

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Hearing recovery from deafness caused by bromate intoxication

The Journal of Laryngology & Otology ◽

10.1017/s0022215118002001 ◽

2018 ◽

Vol 132 (11) ◽

pp. 1039-1041 ◽

Cited By ~ 1

Author(s):

J Suzuki ◽

Y Takanashi ◽

A Koyama ◽

Y Katori

Keyword(s):

Hearing Loss ◽

Sensorineural Hearing Loss ◽

Pure Tone ◽

Pure Tone Audiometry ◽

Auditory Brainstem ◽

Sensorineural Hearing ◽

Auditory Brainstem Responses ◽

Common Symptom ◽

Hearing Recovery ◽

Continuous Haemodiafiltration

AbstractObjectivesSodium bromate is a strong oxidant, and bromate intoxication can cause irreversible severe-to-profound sensorineural hearing loss. This paper reports the first case in the English literature of bromate-induced hearing loss with hearing recovery measured by formal audiological assessment.Case reportA 72-year-old woman was admitted to hospital with complaints of profound hearing loss, nausea, diarrhoea and anuria after bromate ingestion in a suicide attempt. On admission, pure tone audiometry and auditory brainstem responses showed profound bilateral deafness. Under the diagnosis of bromate-induced acute renal failure and sensorineural hearing loss, continuous haemodiafiltration was performed. When dialysis was discontinued, pure tone audiometry and auditory brainstem responses showed partial threshold recovery from profound deafness.ConclusionSevere-to-profound sensorineural hearing loss is a common symptom of bromate intoxication. Bromate-induced hearing loss may be partially treated, and early application of continuous haemodiafiltration might be useful as a treatment for this intractable condition.

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Auditory Brainstem Responses in a Case of High-Frequency Conductive Hearing Loss

Journal of Speech and Hearing Disorders ◽

10.1044/jshd.5004.346 ◽

1985 ◽

Vol 50 (4) ◽

pp. 346-350 ◽

Cited By ~ 8

Author(s):

Michael P. Gorga ◽

Jan K. Reiland ◽

Kathryn A. Beauchaine

Keyword(s):

Hearing Loss ◽

High Frequency ◽

Conductive Hearing Loss ◽

Auditory Brainstem ◽

Intensity Function ◽

Auditory Brainstem Responses ◽

Normal Limits ◽

Interpeak Latency ◽

Lower Limits ◽

Conductive Hearing

Click-evoked auditory brainstem responses were measured in a patient with high-frequency conductive hearing loss. As is typical in cases of conductive hearing loss, Wave I latency was prolonged beyond normal limits. Interpeak latency differences were just below the lower limits of the normal range. The Wave V latency-intensity function, however was abnormally steep. This pattern is explained by the hypothesis that the slope of the latency-intensity function is determined principally by the configuration of the hearing loss. In cases of high-frequency hearing loss (regardless of the etiology), the response may be dominated by more apical regions of the cochlea at lower intensities and thus have a longer latency.

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