Efficacy of different routes of administration for Coenzyme Q10 formulation in noise-induced hearing loss: systemic versus transtympanic modality.

CONCLUSION

The effectiveness of a coenzyme Q10 formulation, Q-ter, given via transtympanic injection is interesting for the future application of this minimally invasive procedure in the treatment of reactive oxygen species (ROS)-induced hearing loss.

OBJECTIVE

We focused on antioxidant therapy in noise-induced hearing loss (NIHL). Our study was designed to evaluate the effectiveness of Q-ter for different schedules of drug administration to establish the best modality for treatment.

METHODS

Rats were exposed to acoustic trauma (10 kHz at 120 dB for 60 min) and received Q-ter according to two modalities: systemic (Q-ter 100 mg/kg for 4 days 1 h before and 3 days post noise exposure) and transtympanic (Q-ter 20 and 40% concentration 1 h before noise exposure). Auditory brainstem response (ABR), immunohistochemical and morphological studies were performed.

RESULTS

Q-ter administration significantly decreased NIHL at day 21 from noise exposure. The improvement of auditory function by Q-ter was paralleled by a significant reduction in oxidative stress. The transtympanic and systemic routes of drug administration showed a similar degree of protection.