Protective role of astaxanthin on noise-induced hearing LOSS

Noise is the most important reason of acquired hearing loss leading to permanent hearing loss. Considering the current literature on the subject to understand the mechanism of noise-induced hearing loss and to protect the inner ear from noise and focus on the identification of agents, we encountered in the literature are not yet efficient method. The aim of this study was to evaluate the otoprotection efficacy of Astaksantin against noise induced hearing loss in a rat animal model. Twenty-one adult male albino Wistar rats divided into two categories including exposed to noise and not exposed to noise. We created not exposed to noise groups which are saline and also exposed to noise groups including saline, Astaxanthin groups. These three groups were administered equal dose (50 mg/kg) by way of intraperitoneally and oral gavage. 14 rats were exposed to 120 dB SPL octave band noise centred at 4 kHz for 4 h. The hearing level of all animals was evaluated with auditory brainstem responses (ABR) at 4 and 8 kHz octave frequencies and distortion product otoacoustic emissions (DPOAE). ABRs were measured before and after noise exposed at 1st day and 7th days. After latest ABR measurement, all animals were sacrificed. ABR results at all frequencies demonstrate that the Astaxanthin group showed more reduced threshold shifts when compared with SS and DMSO group. These shifts were significantly different (p<0.05). These results indicate that Astaxanthin may be useful as a potential post- exposure candidate therapy for NIHL as an antioxidant.