Fig. 4

Autophagy was required for exosome-mediated hearing functional recovery in the neomycin-induced SNHL mice model. A The expression levels of LC3 and SQSTM1/p62 in cochlear tissues were evaluated by western blot after 3-MA treatment and LC3-II and SQSTM1/p62 was quantified by ImageJ software. B ABR thresholds were analyzed in mice with different treatment. Untreated control (Ctrl, black), neomycin alone (Neo, yellow), neomycin and exosome treatment (Neo + Exo, red) 3-MA alone (3-MA, blue), neomycin and 3-MA (Neo + 3-MA, green), and neomycin, exosome and 3-MA (Neo + Exo + 3-MA, pink). n = 6 mice. ##p < 0.01 Ctrl vs. Neo; *p < 0.01; **p < 0.01 Neo vs. Neo + Exo; n.s., not significant Ctrl vs. 3-MA; NS, not significant Neo + 3-MA vs. Neo + Exo + 3-MA by one-way ANOVA. C–E Immunofluorescence staining with Myo 7a (green), F-actin (red), and Hoechst (blue) in the apical (C), middle (D), and basal (E) turns of cochleae from different groups. Scale bars = 50 μm. Quantification of Myo 7a-positive hair cells in the apical (C), middle (D), and basal (E) turns of the cochleae from different groups. The results were representative of the data generated in at least three independent experiments and data were presented as mean ± s.d. n.s., not significant; *P < 0.05; **P < 0.01 by Student’s t-test (A) or by one-way ANOVA (B–E)