scholarly journals Preloaded D-methionine protects from steady state and impulse noise-induced hearing loss and induces long-term cochlear and endogenous antioxidant effects

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261049
Author(s):  
Kathleen Campbell ◽  
Nicole Cosenza ◽  
Robert Meech ◽  
Michael Buhnerkempe ◽  
Jun Qin ◽  
...  

Objective Determine effective preloading timepoints for D-methionine (D-met) otoprotection from steady state or impulse noise and impact on cochlear and serum antioxidant measures. Design D-met started 2.0-, 2.5-, 3.0-, or 3.5- days before steady-state or impulse noise exposure with saline controls. Auditory brainstem response (ABRs) measured from 2 to 20 kHz at baseline and 21 days post-noise. Samples were then collected for serum (SOD, CAT, GR, GPx) and cochlear (GSH, GSSG) antioxidant levels. Study sample Ten Chinchillas per group. Results Preloading D-met significantly reduced ABR threshold shifts for both impulse and steady state noise exposures but with different optimal starting time points and with differences in antioxidant measures. For impulse noise exposure, the 2.0, 2.5, and 3.0 day preloading start provide significant threshold shift protection at all frequencies. Compared to the saline controls, serum GR for the 3.0 and 3.5 day preloading groups was significantly increased at 21 days with no significant increase in SOD, CAT or GPx for any impulse preloading time point. Cochlear GSH, GSSG, and GSH/GSSG ratio were not significantly different from saline controls at 21 days post noise exposure. For steady state noise exposure, significant threshold shift protection occurred at all frequencies for the 3.5, 3.0 and 2.5 day preloading start times but protection only occurred at 3 of the 6 test frequencies for the 2.0 day preloading start point. Compared to the saline controls, preloaded D-met steady-state noise groups demonstrated significantly higher serum SOD for the 2.5–3.5 day starting time points and GPx for the 2.5 day starting time but no significant increase in GR or CAT for any preloading time point. Compared to saline controls, D-met significantly increased cochlear GSH concentrations in the 2 and 2.5 day steady-state noise exposed groups but no significant differences in GSSG or the GSH/GSSG ratio were noted for any steady state noise-exposed group. Conclusions The optimal D-met preloading starting time window is earlier for steady state (3.5–2.5 days) than impulse noise (3.0–2.0). At 21 days post impulse noise, D-met increased serum GR for 2 preloading time points but not SOD, CAT, or GpX and not cochlear GSH, GSSG or the GSH/GSSG ratio. At 21 days post steady state noise D-met increased serum SOD and GPx at select preloading time points but not CAT or GR. However D-met did increase the cochlear GSH at select preloading time points but not GSSG or the GSH/GSSG ratio.

2002 ◽  
Vol 13 (05) ◽  
pp. 227-235 ◽  
Author(s):  
Kathy R. Vander Werff ◽  
Carolyn J. Brown ◽  
Barbara A. Gienapp ◽  
Kelly M. Schmidt Clay

Recently, auditory steady-state responses (ASSRs) have been proposed as an alternative to the auditory brainstem response (ABR) for threshold estimation. The goal of this study was to investigate the degree to which ASSR thresholds correlate with ABR thresholds for a group of sedated children with a range of hearing losses. Thirty-two children from the University of Iowa Hospitals and Clinics ranging in age from 2 months to 3 years and presenting with a range of ABR thresholds participated. Strong correlations were found between the 2000-Hz ASSR thresholds and click ABR thresholds (r = .96), the average of the 2000- and 4000-Hz ASSR thresholds and click ABR thresholds (r = .97), and the 500-Hz ASSR and 500-Hz toneburst ABR thresholds (r = .86). Additionally, it was possible to measure ASSR thresholds for several children with hearing loss that was great enough to result in no ABR at the limits of the equipment. The results of this study indicate that the ASSR may provide a reasonable alternative to the ABR for estimating audiometric thresholds in very young children.


Marine Drugs ◽  
2021 ◽  
Vol 19 (8) ◽  
pp. 443
Author(s):  
Hyunjun Woo ◽  
Min-Kyung Kim ◽  
Sohyeon Park ◽  
Seung-Hee Han ◽  
Hyeon-Cheol Shin ◽  
...  

One of the well-known causes of hearing loss is noise. Approximately 31.1% of Americans between the ages of 20 and 69 years (61.1 million people) have high-frequency hearing loss associated with noise exposure. In addition, recurrent noise exposure can accelerate age-related hearing loss. Phlorofucofuroeckol A (PFF-A) and dieckol, polyphenols extracted from the brown alga Ecklonia cava, are potent antioxidant agents. In this study, we investigated the effect of PFF-A and dieckol on the consequences of noise exposure in mice. In 1,1-diphenyl-2-picrylhydrazyl assay, dieckol and PFF-A both showed significant radical-scavenging activity. The mice were exposed to 115 dB SPL of noise one single time for 2 h. Auditory brainstem response(ABR) threshold shifts 4 h after 4 kHz noise exposure in mice that received dieckol were significantly lower than those in the saline with noise group. The high-PFF-A group showed a lower threshold shift at click and 16 kHz 1 day after noise exposure than the control group. The high-PFF-A group also showed higher hair cell survival than in the control at 3 days after exposure in the apical turn. These results suggest that noise-induced hair cell damage in cochlear and the ABR threshold shift can be alleviated by dieckol and PFF-A in the mouse. Derivatives of these compounds may be applied to individuals who are inevitably exposed to noise, contributing to the prevention of noise-induced hearing loss with a low probability of adverse effects.


2019 ◽  
Vol 35 (2) ◽  
Author(s):  
Muhammad Azeem Aslam ◽  
Adeela Javed ◽  
Abdul Moiz

Objectives: To compare the hearing thresholds obtained with auditory brainstem response (ABR) and auditory steady state response (ASSR) audiometry in children with hearing loss. Methods: Hearing thresholds were obtained by ABR and ASSR in children who presented with suspicion of deafness at Ear, nose & throat department of Al-Nafees Medical College Hospital Islamabad, between January to August 2018. The mean hearing thresholds obtained by two tests were compared within each category of severity of deafness. Time taken by both tests was also compared. Results: A total of 57 patients (114 ears) were included in the study. Among them 27 (47.4%) were male and 30 (52.6%) were female. The mean age of patients at presentation was 42 months (±30.9) with age range from one to 12 years. Mean hearing thresholds obtained by click ABR, chirp ABR, ASSR (1, 2, 4 kHz) & ASSR (0.5, 1, 2, 4 kHz) was 56.25 (±27.61), 58.88 (±27.44), 58.03 (±21.26) & 56.35 (±22.86) respectively. Mean thresholds were comparable between click ABR & ASSR (1, 2, 4 kHz) and between chirp ABR & ASSR (0.5, 1, 2, 4 kHz) in all degrees of hearing loss categories except in those patients with normal hearing thresholds. The mean time taken by clicks ABR, chirp ABR and ASSR were four minutes seven seconds, three minutes 15 seconds and 16 minutes and 7 seconds respectively. Conclusions: Hearing thresholds obtained by ABR and ASSR are comparable in all categories of severity of hearing loss. The time taken by ABR is less as compared to ASSR. How to cite this:Aslam MA, Javed A, Moiz A. Comparison of auditory brainstem response and auditory steady state response audiometry by evaluating the hearing thresholds obtained in children with different severity of hearing loss. Pak J Med Sci. 2019;35(2):---------.   doi: https://doi.org/10.12669/pjms.35.2.688 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


2019 ◽  
Vol 2 (1) ◽  
pp. 17-21
Author(s):  
Adil Munir ◽  
Nazia Mumtaz ◽  
Ghulam Saqulain ◽  
Munir Ahmad

Objective: Hearing loss (HL) with a local prevalence of 5.7%, is the commonest childhood disability, requiring Early Hearing Detection and Intervention (EHDI) programs to reduce the disability burden. Knowing the degree, type and configuration of HL is prerequisite for appropriate amplification, with Automated Auditory Brainstem Responses (ABR) being commonly used for this purpose, however Auditory Steady State Response (ASSR) has been recently introduced in the region. This study was conducted to compare ABR to ASSR, as an early diagnostic tool in children under five years of age. Methodology: This cross-sectional comparative study was performed at the Auditory Verbal Institute of Audiology and Speech (AVIAS) clinics in Rawalpindi and Islamabad, from December 2016 to September 2017. It included thirty-two cases (n=32) who visited AVIAS clinics for hearing assessment and conformed to the investigative protocol using non probability convenient sampling technique, and subjected to both ABR and ASSR for comparative purposes. Correlations were calculated between the thresholds obtained by ABR and ASSR. Results: N=32 children (64 ears) with male female ratio of 2.2:1 and mean age of 33.50±17.73 months were tested with ABR and ASSR for hearing thresholds and correlation coefficient between 2KHz, 4KHz ASSR and average of both with ABR was calculated to be 0.92 and 0.90 and 0.94 respectively. Conclusion: ASSR provides additional frequency specific hearing threshold estimation compared to C-ABR, essentially required for proper setting of amplification devices. 


2016 ◽  
Vol 43 (1) ◽  
pp. 78-86
Author(s):  
Chihiro Morimoto ◽  
Kazuhiko Nario ◽  
Tadashi Nishimura ◽  
Ryota Shimokura ◽  
Hiroshi Hosoi ◽  
...  

1994 ◽  
Vol 159 (11) ◽  
pp. 676-680 ◽  
Author(s):  
Linda L. Pierson ◽  
Kenneth J. Gerhardt ◽  
Robert M. Abrams ◽  
Scott K. Griffiths ◽  
Aemil J.M. Peters

2017 ◽  
Vol 38 (1) ◽  
pp. e1-e12 ◽  
Author(s):  
Naomi F. Bramhall ◽  
Dawn Konrad-Martin ◽  
Garnett P. McMillan ◽  
Susan E. Griest

2010 ◽  
Vol 124 (9) ◽  
pp. 950-956 ◽  
Author(s):  
A A Emara ◽  
T A Gabr

AbstractReview:Auditory neuropathy is a disorder characterised by preservation of outer hair cell function, with normal otoacoustic emissions and/or cochlear microphonics, but an absent or distorted auditory brainstem response.Purpose:This study aimed to objectively assess hearing thresholds in patients with auditory neuropathy, using the auditory steady state response.Materials and methods:Thirteen patients with auditory neuropathy and 15 normal hearing subjects were examined. Audiological evaluation included basic audiological tests, otoacoustic emissions, auditory brainstem response and auditory steady state response.Results:In the auditory neuropathy patients, the auditory brainstem response was absent in 11 patients, while the auditory steady state response was absent in only three.Conclusion:The auditory steady state response may serve as a valuable objective measure for assessing the hearing threshold across different frequencies in patients with auditory neuropathy. We recommend that auditory steady state response be used to complete the evaluation of patients with auditory neuropathy.


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