Effect of oral magnesium supplementation on cisplatin ototoxicity.

OBJECTIVE: The purpose of this study is to evaluate the effect of Mg supplementation on cisplatin ototoxicity in guinea pigs.

METHODS: Twenty guinea pigs were divided into two groups and were fed different Mg-containing diets. Following 6 mg/kg of cisplatin injection, the animals were sacrificed and the extent of cochlear damage was assessed with the scanning electron microscope and compared with the control group. Additionally, intracardiac blood samples were taken to determine the plasma Mg levels of the subjects before and after cisplatin exposure.

RESULTS: The outer hair cell damage owing to cisplatin was not statistically different in both groups (p > .05). Following cisplatin injection, the plasma Mg levels of both groups were found to be significantly lower than the plasma Mg levels before exposure, but the resulting values of the Mg-rich fed group was compatible with control group Mg levels.

CONCLUSION: Our study showed that a Mg-rich diet can prevent the severe hypomagnesemia that cisplatin causes in guinea pigs, but this measure has not been enough to protect the inner ear against its ototoxic effect.