TY - JOUR
T1 - Chronic exposure to low frequency noise at moderate levels causes impaired balance in mice
AU - Tamura, Haruka
AU - Ohgami, Nobutaka
AU - Yajima, Ichiro
AU - Iida, Machiko
AU - Ohgami, Kyoko
AU - Fujii, Noriko
AU - Itabe, Hiroyuki
AU - Kusudo, Tastuya
AU - Yamashita, Hitoshi
AU - Kato, Masashi
N1 - Copyright:
Copyright 2013 Elsevier B.V., All rights reserved.
PY - 2012/6/29
Y1 - 2012/6/29
N2 - We are routinely exposed to low frequency noise (LFN; below 0.5 kHz) at moderate levels of 60-70 dB sound pressure level (SPL) generated from various sources in occupational and daily environments. LFN has been reported to affect balance in humans. However, there is limited information about the influence of chronic exposure to LFN at moderate levels for balance. In this study, we investigated whether chronic exposure to LFN at a moderate level of 70 dB SPL affects the vestibule, which is one of the organs responsible for balance in mice. Wild-type ICR mice were exposed for 1 month to LFN (0.1 kHz) and high frequency noise (HFN; 16 kHz) at 70 dB SPL at a distance of approximately 10-20 cm. Behavior analyses including rotarod, beam-crossing and footprint analyses showed impairments of balance in LFN-exposed mice but not in non-exposed mice or HFN-exposed mice. Immunohistochemical analysis showed a decreased number of vestibular hair cells and increased levels of oxidative stress in LFN-exposed mice compared to those in non-exposed mice. Our results suggest that chronic exposure to LFN at moderate levels causes impaired balance involving morphological impairments of the vestibule with enhanced levels of oxidative stress. Thus, the results of this study indicate the importance of considering the risk of chronic exposure to LFN at a moderate level for imbalance.
AB - We are routinely exposed to low frequency noise (LFN; below 0.5 kHz) at moderate levels of 60-70 dB sound pressure level (SPL) generated from various sources in occupational and daily environments. LFN has been reported to affect balance in humans. However, there is limited information about the influence of chronic exposure to LFN at moderate levels for balance. In this study, we investigated whether chronic exposure to LFN at a moderate level of 70 dB SPL affects the vestibule, which is one of the organs responsible for balance in mice. Wild-type ICR mice were exposed for 1 month to LFN (0.1 kHz) and high frequency noise (HFN; 16 kHz) at 70 dB SPL at a distance of approximately 10-20 cm. Behavior analyses including rotarod, beam-crossing and footprint analyses showed impairments of balance in LFN-exposed mice but not in non-exposed mice or HFN-exposed mice. Immunohistochemical analysis showed a decreased number of vestibular hair cells and increased levels of oxidative stress in LFN-exposed mice compared to those in non-exposed mice. Our results suggest that chronic exposure to LFN at moderate levels causes impaired balance involving morphological impairments of the vestibule with enhanced levels of oxidative stress. Thus, the results of this study indicate the importance of considering the risk of chronic exposure to LFN at a moderate level for imbalance.
UR - http://www.scopus.com/inward/record.url?scp=84863111254&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84863111254&partnerID=8YFLogxK
U2 - 10.1371/journal.pone.0039807
DO - 10.1371/journal.pone.0039807
M3 - Article
C2 - 22768129
AN - SCOPUS:84863111254
VL - 7
JO - PLoS One
JF - PLoS One
SN - 1932-6203
IS - 6
M1 - e39807
ER -