Reduction of cisplatin ototoxicity in rats by oral administration of pomegranate extract.

The aim of this study was to investigate the effectiveness of the oral administration of pomegranate extract (PE) as a protective agent against cisplatin-induced ototoxicity. The study included a prospective, controlled animal study Group 1 (n = 6), received no cisplatin or PE, and group 2 (n = 6) received cisplatin at 8 mg/kg/day for 3 consecutive days. Group 3 (n = 6) received not only cisplatin at 8 mg/kg/day for 3 consecutive days, but also received PE (100 μL/day) via gavage for 5 days prior to the cisplatin injection and for 3 days concomitantly with the cisplatin injections. To measure cisplatin ototoxic effects, "distortion product otoacoustic emissions" (DPOAE) were analyzed 3 days before and after the cisplatin injections. Histological changes in the cochleas were observed by light microscopy. Compared with group 3, the DPOAE amplitudes of group 2 decreased significantly. Among the groups, there was a statistically significant difference in basal and mid turn external ciliated cells (ECC) number, but there was no statistically significant difference in apical turn. Differences in stria vascularis (SV) changes were statistically significant between the groups, and the median score for SV injury was significantly greater in group 2 than in group 3. Differences in the median scores for SGC changes being significantly greater in group 2 than in group 3. In conclusion, these results indicated that oral administration of PE afforded statistically significant protection to the cochlea in rats from cisplatin toxicity, and thus, oral experimental dose of PE administration may have a protective effect against cisplatin ototoxicity in rats.