Correlation of SOD and MDA Expression in the Organ of Corti and Changes in the Function of Outer Hair Cells Measured by DPOAE Examination in Noise-Exposed Rat Cochlea

Abstract

Background: Hearing loss due to noise can cause the disturbances toward the quality of life and cause mechanical damage and metabolic decompensation. Distortion Product Otoacoustic Emission (DPOAE) is an examination to assess the sensory function of outer hair cells. Superoxide Dismutase (SOD) and Malondialdehyde (MDA) are markers of oxidative stress. The aim of this study was to identify the correlation between DPOAE examination and SOD and MDA expression in rats exposed to noise. Methods: This research was conducted on 27 rats which were divided into 3 groups, group 1 (control), group 2, and group 3 were groups with 100 dB and 110 dB noise exposure respectively. Results: Our findings show a decrease in SOD expression and DPOAE values as well as an increase in MDA expression in rats exposed to noise and there is a positive correlation between Signal to Noise Ratio (SNR) value with SOD expression (r= 0.733, p= 0.025) and a negative correlation between SNR value with MDA expression (r= -0.678, p= 0.045). Conclusions: our study find the correlation of oxidant and antioxidant status values in the organ of corti and changes in the function of outer hair cells in noise-exposed rat models.