Protective role of edaravone against cisplatin-induced ototoxicity in an auditory cell line

Edaravone is a neuroprotective agent with a potent free radical scavenging and antioxidant actions. In the present study we investigated the influence of edaravone on cisplatin ototoxicity in auditory cells. Cell viability was determined using a 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide cell proliferation assay. Oxidative stress and apoptosis were assessed by reactive oxygen species (ROS) measurement, Hoechst 33258 staining, caspase-3 activity assay, and immunoblotting of PARP. Pretreatment with 100 μM of edaravone prior to application of 15 μM of cisplatin increased cell viability after 48 h of incubation in HEI-OC1 cells (from 51.9% to 64. 6% viability) and also, attenuated the cisplatin-induced increase in reactive oxygen species (ROS) (from 2.3 fold to 1.9 fold). Edaravone also decreased the activation of caspase-3 and reduced levels of cleaved poly-ADP-ribose polymerase (PARP). We propose that edaravone protects against cisplatin-induced ototoxicity by preventing apoptosis, and limiting ROS production in HEI-OC1 cells.