Preventive effect of curcumin and its highly bioavailable preparation on hearing loss induced by single or repeated exposure to noise: A comparative and mechanistic study

We sought to determine the preventive effects of curcumin and its highly bioavailable preparation on noise-induced hearing loss in a novel murine model of permanent hearing loss developed by repeated exposure to noise. upon exposure to noise (8-khz octave band noise,90 db sound pressure level,1 h),hearing ability was impaired in a temporary and reversible manner. during repeated noise exposure (1-h exposure per day,5 days),there was a progressive increase in the auditory threshold shift at 12 and 20 khz. the threshold shift persisted for at least 6 days after noise exposure. oral administration of curcumin for 3 days before and each day during noise exposure significantly alleviated the hearing loss induced by repeated noise exposure. curcumin abolished intranuclear translocation of nuclear factor-κb-p65 and generation of 4-hydroxynonenal-adducted proteins found in the cochlea after noise exposure. theracurmin®,a highly absorbable and bioavailable preparation of curcumin,had strong preventive effects on hearing loss induced by repeated noise exposure. together,these data suggest that curcumin exerts a preventive effect on noise-induced hearing loss and is therefore a good therapeutic candidate for preventing sensorineural hearing loss. © 2017 the authors