The Antiapoptotic Effect of Curcumin in the Fibroblast of the Cochlea in an Ototoxic Rat Model

Abstract

This study aimed to show the potency of curcumin as an antiapoptotic agent that decreases the apoptotic index in the cochlea lateral wall in ototoxic rat models. A total of 24 Rattus norvegicus were divided into eight groups: Group 1 (control group), Group 2 (gentamicin (+)), Group 3 (gentamicin + curcumin 20 mg/day), Group 4 (gentamicin + curcumin 40 mg/day), Group 5 (gentamicin + curcumin 20 mg/day for 7 days), Group 6 (gentamicin + curcumin 40 mg/day for 7 days), Group 7 (curcumin 20 mg/day for 3 days + gentamicin), and Group 8 (curcumin 40 mg/day for 3 days + gentamicin). After the division, the rats were terminated in order to measure the apoptotic index using a terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) assay in the fibroblasts of the cochlea lateral walls. The data were analyzed using analysis of variance (ANOVA), and P<0.05 was used as the cut-off for statistical significance. Administration of gentamicin showed significant differences (P<0.05) in the apoptotic index. Groups undergoing curcumin treatment at a higher dose (200 mg/kg bw) and the prevention groups showed significant differences compared with groups not treated with curcumin. This study concluded that the apoptotic index can be decreased by curcumin and has a preventive benefit toward ototoxic rat models. The administration of curcumin depended on the dose and duration.