TY - JOUR TI - The effect of time regime in noise exposure on the auditory system and behavioural stress in the zebrafish AU - Wong, Man Ieng AU - Lau, Ieng Hou AU - Gordillo-Martinez, Flora AU - Vasconcelos, Raquel O. T2 - Scientific Reports AB - Anthropogenic noise of variable temporal patterns is increasing in aquatic environments, causing physiological stress and sensory impairment. However, scarce information exists on exposure effects to continuous versus intermittent disturbances, which is critical for noise sustainable management. We tested the effects of different noise regimes on the auditory system and behaviour in the zebrafish (Danio rerio). Adult zebrafish were exposed for 24 h to either white noise (150 ± 10 dB re 1 μPa) or silent control. Acoustic playbacks varied in temporal patterns—continuous, fast and slow regular intermittent, and irregular intermittent. Auditory sensitivity was assessed with Auditory Evoked Potential recordings, revealing hearing loss and increased response latency in all noise-treated groups. The highest mean threshold shifts (c. 13 dB) were registered in continuous and fast intermittent treatments, and no differences were found between regular and irregular regimes. Inner ear saccule did not reveal significant hair cell loss but showed a decrease in presynaptic Ribeye b protein especially after continuous exposure. Behavioural assessment using the standardized Novel Tank Diving assay showed that all noise-treated fish spent > 98% time in the bottom within the first minute compared to 82% in control, indicating noise-induced anxiety/stress. We provide first data on how different noise time regimes impact a reference fish model, suggesting that overall acoustic energy is more important than regularity when predicting noise effects. DA - 2022/09/12/ PY - 2022 DO - 10.1038/s41598-022-19573-y DP - www.nature.com VL - 12 IS - 1 SP - 15353 J2 - Sci Rep LA - en SN - 2045-2322 UR - https://www.nature.com/articles/s41598-022-19573-y Y2 - 2022/09/21/08:11:43 KW - Ecology KW - Neuroscience KW - Physiology KW - Zoology ER - TY - JOUR TI - Noise-induced hearing loss in zebrafish: investigating structural and functional inner ear damage and recovery AU - Breitzler, Lukas AU - Lau, Ieng Hou AU - Fonseca, Paulo J. AU - Vasconcelos, Raquel O. T2 - Hearing Research AB - Exposure to continuous moderate noise levels is known to impair the auditory system leading to Noise-Induced Hearing Loss (NIHL) in animals including humans. The mechanism underlying noise-dependent auditory Temporary Threshold Shifts (TTS) is not fully understood. In fact, only limited information is available on vertebrates such as fishes, which share homologous inner ear structures to mammals and have the ability to regenerate hair cells. The zebrafish Danio rerio is a well-established model in hearing research providing an unmatched opportunity to investigate the molecular and physiological mechanisms of NIHL at the sensory receptor level. Here we investigated for the first time the effects of noise exposure on TTS and functional recovery in zebrafish, as well as the associated morphological damage and regeneration of the inner ear saccular hair cells. Adult specimens were exposed for 24h to white noise at various amplitudes (130, 140 and 150 dB re. 1 μPa) and their auditory sensitivity was subsequently measured with the Auditory Evoked Potential (AEP) recording technique. Sensory recovery was tested at different times post-treatment (after 3, 7 and 14 days) and compared to individuals kept under quiet lab conditions. Results revealed noise level-dependent TTS up to 33 dB and increase in response latency. Recovery of hearing function occurred within 7 days for fish exposed to 130 and 140 dB noise levels, while fish subject to 150 dB only returned to baseline thresholds after 14 days. Hearing impairment was accompanied by significant loss of hair cells only at the highest noise treatment. Full regeneration of the sensory tissue (number of hair cell receptors) occurred within 7 days, which was prior to functional recovery. We provide first baseline data of NIHL in zebrafish and validate this species as an effective vertebrate model to investigate the impact of noise exposure on the structure and function of the adult inner ear and its recovery process. DA - 2020/06/01/ PY - 2020 DO - 10.1016/j.heares.2020.107952 DP - ScienceDirect VL - 391 SP - 107952 J2 - Hearing Research LA - en SN - 0378-5955 ST - Noise-induced hearing loss in zebrafish UR - https://www.sciencedirect.com/science/article/pii/S0378595519304587 Y2 - 2022/09/21/08:12:14 KW - Fish KW - Hair cells KW - Hearing sensitivity KW - Noise KW - Sound pressure level KW - Temporary threshold shift ER - TY - JOUR TI - Noise-induced hearing loss correlates with inner ear hair cell decrease in larval zebrafish AU - Lara, Rafael A. AU - Breitzler, Lukas AU - Lau, Ieng Hou AU - Gordillo-Martinez, Flora AU - Chen, Fangyi AU - Fonseca, Paulo J. AU - Bass, Andrew H. AU - Vasconcelos, Raquel O. T2 - Journal of Experimental Biology AB - Anthropogenic noise can be hazardous for the auditory system and wellbeing of animals, including humans. However, very limited information is known on how this global environmental pollutant affects auditory function and inner ear sensory receptors in early ontogeny. The zebrafish (Danio rerio) is a valuable model in hearing research, including investigations of developmental processes of the vertebrate inner ear. We tested the effects of chronic exposure to white noise in larval zebrafish on inner ear saccular sensitivity and morphology at 3 and 5 days post-fertilization (dpf), as well as on auditory-evoked swimming responses using the prepulse inhibition (PPI) paradigm at 5 dpf. Noise-exposed larvae showed a significant increase in microphonic potential thresholds at low frequencies, 100 and 200 Hz, while the PPI revealed a hypersensitization effect and a similar threshold shift at 200 Hz. Auditory sensitivity changes were accompanied by a decrease in saccular hair cell number and epithelium area. In aggregate, the results reveal noise-induced effects on inner ear structure–function in a larval fish paralleled by a decrease in auditory-evoked sensorimotor responses. More broadly, this study highlights the importance of investigating the impact of environmental noise on early development of sensory and behavioural responsiveness to acoustic stimuli. DA - 2022/04/06/ PY - 2022 DO - 10.1242/jeb.243743 DP - Silverchair VL - 225 IS - 7 SP - jeb243743 J2 - Journal of Experimental Biology SN - 0022-0949 UR - https://doi.org/10.1242/jeb.243743 Y2 - 2022/09/21/08:11:47 ER -