Figure 2
Hydroxamate (-)-9 increases outer hair cell survival in response to aminoglycoside toxicity. (A) Cochlear explants were subjected to either 1 mM neomycin for 6 h or 500 µM sisomicin for 1 h, and allowed to recover for 48 h. Hydroxamate (-)-9 was applied at 100 nM for 14 h prior to aminoglycoside exposure. ISRIB (200 nM) was co-applied with neomycin or sisomicin and then maintained in an aminoglycoside-free medium for 24 h. All samples were allowed to recover for 48 h in an aminoglycoside-free medium before fixation. Anti-myosinVIIa used to label IHCs and OHCs. Arrows, examples of surviving OHCs after aminoglycoside treatment. All treatments were performed using the mid-sections of the basal cochlear coils, where the strongest effects on hair cell loss after neomycin or sisomicin application are observed. Images are average intensity Z-projections from confocal stacks. Lower, colour merge panels are orthogonal (YZ) projections from the confocal stacks. Scale bar = 10 µm. (B, C) Graphs show average number of surviving OHC and IHC, respectively. Error bars, SEM. *p < 0.05 **p < 0.01, Student’s t-test. Data were obtained from at least three separate experiments. Each n represents a separate basal cochlear explant as follows: control (n = 6), neomycin (n = 7), sisomicin (n = 7) hydroxamate (-)-9 + neomycin (n = 9), hydroxamate (-)-9 + sisomicin (n = 7), neomycin + ISRIB (n = 4), sisomicin + ISRIB (n = 9).
