The effect of coenzyme Q10 on cisplatin-induced ototoxicity in rats

Objective: To determine the efficacy of systemic administration of coenzyme Q10 at low and high doses on cisplatin-induced ototoxicity in rats. Methods: Our study was performed with 40 Sprague-Dawley rats. They were divided randomly into five groups: Cis, Cis+Q10(30), Cis+Q10(10), Q10, and control. Cis (n=8) group was administered cisplatin [ a single intraperitoneal (i.p.) injection of 14 mg/kg], Cis+Q10(30) (n=8) group was administered cisplatin (a single i.p. injection of 14 mg/kg) and coenzyme Q10 (30 mg/kg/day, i.p.) for 3 days, Cis+Q10(10) (n=8) group was given cisplatin (a single dose of 14 mg/kg/day, i.p.) and coenzyme Q10 (10 mg/kg/day, i.p.) for 3 days, Q10 (n=8) group was administered coenzyme Q10 (10 mg/kg/day, i.p.) for 3 days and Group C (n=8) (control group) was administered saline solution (1 mL/day, i.p.) once daily for 3 days. Pretreatment and posttreatment hearing levels were evaluated with distortion product otoacoustic emissions (DPOAEs). Results: There was no statistically significant difference in the results of measurements of 4004, 4358, 4761 and 5188 Hz at end of the study in comparison to baseline (p>0.05). On the other hand, there was a significant difference at the measurements of 5652, 6165, 7336 and 7996 Hz (p=0.002, p=0.037, p=0.001, p=0.001, respectively). The rate of change at 5652 Hz revealed that Cis group was different from Cis+Q10(10), control and Q10 groups (p<0.01); measurements at 6165 Hz revealed that change at Cis group was significantly different from control and Q10 groups (p<0.01, p<0.05). Final measurements of decrease in Cis group at 7336 and 7996 Hz were significantly different from baseline (p<0.05; p<0.01). Conclusion: The high-dose coenzyme Q10 showed a protective effect on hearing in cisplatin-induced ototoxicity while low-dose coenzyme Q10 protected hearing at low frequencies but did not show protective effect at high frequencies.