Effect of Carbon Monoxide-Releasing Molecule-3 on Auditory and Histopathological Outcomes in Rats Exposed to Acoustic Trauma: A Study of Antioxidant and Cytoprotective Pathways.

BACKGROUND

The study aims to demonstrate the possible protective effects of carbon monoxide-releasing molecule-3 (CORM-3) on the auditory system after noise exposure through electrophysiological measurements and histopathological methods.

METHODS

Twenty-four albino Wistar male rats were included in the study. They were equally divided into 3 groups. The control group was administered intraperitoneal physiological saline for 7 days. Eight rats in the second group were exposed to 4 kHz octave band noise at 120 dB SPL intensity for 4 hours, and then intraperitoneal saline was administered for 7 days. Group 3, after exposure to noise with the same characteristics, was administered 10 mg/kg of CORM-3 intraperitoneally for 7 days. Hearing levels were measured at baseline, on the first, and seventh days with distortion product otoacoustic emissions (DPOAEs) and auditory evoked brainstem potentials at 4, 6, and 8 kHz. After the measurements, the cochlear structures of all rats were dissected, and the cochlear structures were evaluated by light microscopy.

RESULTS

Auditory evoked brainstem potential test results showed that the CORM-3 group had better hearing thresholds at all frequencies than the other group exposed to noise. These findings were statistically significant (P < .05). The DPOAE responses disappeared after acoustic trauma. Histopathological evaluation showed cellular damage caused by noise in the cochlea.

CONCLUSION

The findings suggest that CORM-3 may be an effective protective and therapeutic agent against noise-induced hearing loss. However, additional research is needed to prove this protective effect.