To investigate the effectiveness of pomegranate extract as protection against aminoglycoside ototoxicity.

Prospective, randomised, controlled, experimental study.

Eighteen Wistar albino rats were randomly allocated to 5 days of either: saline injections; gentamicin injections; or pomegranate extract (100 µl/day via gavage) plus gentamicin injections. Distortion product otoacoustic emissions were tested before treatment and on day 3. After treatment, reactive oxygen species levels were measured in each rat's right cochlea and right kidney via chemiluminescence.

Baseline emission amplitudes were similar. Post-treatment emissions differed significantly in the two treatment groups (p < 0.001). Cochlear reactive oxygen species levels were significantly higher in the gentamicin group (mean ± standard deviation, 316.6 ± 36.5 relative light units per mg) than the gentamicin plus pomegranate extract group (240 ± 24.6 relative light units per mg) (p = 0.004); control group levels were 119.1 ± 10.3 relative light units per mg. Renal reactive oxygen species levels were similar for the control and gentamicin plus pomegranate extract groups (p = 0.59) but much higher in the gentamicin group (p = 0.004).

Concurrent systemic pomegranate extract administration reduced reactive oxygen species level increases and otoacoustic emission changes, following aminoglycoside injection.

To assess the effect of pomegranate extract on acute inflammation due to myringotomy.

Prospective, randomised study.

Thirty Sprague–Dawley rats were divided into three groups. Group one constituted controls. Group two underwent myringotomy. Group three underwent myringotomy and also received 100 µl/day pomegranate extract, via gavage, one day before and two days after surgery. Following sacrifice 48 hours after myringotomy, the animals' right ears were used to determine the concentration of reactive oxygen species, using the chemiluminescence method; left ears were used for histological study.

Reactive oxygen species levels were significantly decreased in group three compared with group two (p < 0.01). The density of inflammatory cells in group three was significantly less than that in group two (p < 0.01). Lamina propria thickness and vessel density were also significantly decreased in group three compared with group two (p < 0.01).

Our results indicate that oral pomegranate extract decreases reactive oxygen species concentration and acute inflammation in the tympanic membrane after myringotomy.