(A) Effect of Sirt3 overexpression in cochlear explant culture on gentamicin-induced hair cell damage. Cultures were infected with control lentivirus-Vector (a, c) or lenti-Sirt3 (b, d), and labeled with TRITC-phalloidin. Additional gentamicin treatment was indicated (c, d). Quantitative analysis of hair cell numbers in cochlear explant cultures (a–d) was summarized in (e). Q-PCR measurement of relative Sirt3 mRNA levels in Vector or lenti-Sirt3 treated cochlear explant was shown in (f). (B) Knockdown of Sirt3 expression in cochlear explant culture attenuated hair cell protection by adjudin. Cultures were infected with NT shRNA (a, c) or sh-Sirt3 (b, d), and labeled with FITC-phalloidin. Additional treatment with gentamicin + adjudin was indicated (c, d). Quantitative analysis of hair cell numbers in cochlear explant cultures (a–d) was summarized in (e). Q-PCR measurement of relative Sirt3 mRNA levels in NT-shRNA or sh-Sirt3 treated cochlear explant was shown in (f). NT shRNA, Non-targeting control shRNA. Data were collected from five or more cultures in each group and are expressed as means ± SEM. (A:e, B:e) *p < 0.05; **p < 0.01, two-way ANOVA of the parameters between various regimens, followed by post-hoc tests; (A:f, B:f) ***p < 0.001, student's t test. Bar = 10 μm.