Minocycline Protects Vestibular Hair Cells from Neomycin-Induced Ototoxicity by Inhibiting Reactive Oxygen Species Production and Caspase-3 Activity / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Aminoglycosides, a commonly used antibiotic agent, destroys the sensory hair cells in the cochlear and vestibular system leading to irreversible hearing loss and balance problem. Minocycline, a second-generation tetracycline antibiotic, has been known to possess anti-apoptotic properties in addition to its antimicrobial action. We hypothesized that minocycline would attenuate aminoglycosides induced vestibulotoxicity in rat utricles. SUBJECTS AND METHOD: Utricular maculae prepared from postnatal day 3-4 rats were treated with neomycin alone or in combination with minocycline. For hair cell count, utricles were stained with phalloidin-FITC. Reactive oxygen species (ROS) was assessed using the fluorescent probe, hydrofluorescent diacetate acetyl ester (H2DCFDA). Caspase-3 activity was also examined using the fluorescent caspase-3 substrate. RESULTS: Neomycin induced dose-dependent loss of utricular hair cells. Minocycline reduced ROS production and caspase-3 activation in neomycin treated utricular hair cells. CONCLUSION: Minocycline has protective effect in neomycin induced ototoxicity in rat utricle by inhibiting ROS production and caspase-3 activity.