title: Sodium Selenite Acts as an Otoprotectant against Neomycin-Induced Hair Cell Damage in a Zebrafish Model.
abstract: Sodium selenite is a trace element essential for many physiological functions in the body. It is involved in various biological processes; it acts as a cofactor for antioxidant enzymes that protect against free radicals and is reported to limit metal-mediated oxidative DNA damage. In the present study, we investigated the effect of sodium selenite on neomycin ototoxicity in wild-type and transgenic zebrafish (Brn3C: EGFP). Five or six days post-fertilization, zebrafish larvae were co-exposed to 125 μM neomycin and various concentrations (10 μM, 100 μM, 250 μM, and 500 μM) of sodium selenite for 1 h. Hair cells within neuromasts of the supraorbital (SO1 and SO2), otic (O1), and occipital (OC1) lateral lines were analyzed by fluorescence microscopy (n = 10 fish per treatment). Hair cell survival was estimated as the ratio of the hair cell numbers in each group compared to those of the control group that were not exposed to neomycin. Apoptosis and hair cell damage of neuromasts were evaluated using the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) assay and 2-[4-(dimethylamino) styryl]-N-ethylpyridinium iodide (DASPEI) assay, respectively. Ultrastructural changes were evaluated using scanning electron microscopy and transmission electron microscopy. Neuromast hair cells were preserved in zebrafish exposed to 125 μM neomycin and 500 μM sodium selenite for 1 h. Sodium selenite protected against neomycin-induced hair cell loss of neuromasts, reduced apoptosis, and prevented zebrafish ultrastructural changes. We propose that sodium selenite protects against neomycin-induced hair cell damage by inhibiting apoptosis, decreasing the disarray of stereocilia, and preventing ultrastructural changes in the neuromast hair cells of the zebrafish.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Hallym University College of Medicine, Seoul, Korea.
authors.forename: Jiwon
authors.initials: J
authors.lastname: Chang
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea.
authors.forename: June
authors.initials: J
authors.lastname: Choi
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea.
authors.forename: Yoon Chan
authors.initials: YC
authors.lastname: Rah
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea.
authors.forename: Myung Hoon
authors.initials: MH
authors.lastname: Yoo
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea.
authors.forename: Kyoung Ho
authors.initials: KH
authors.lastname: Oh
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea.
authors.forename: Gi Jung
authors.initials: GJ
authors.lastname: Im
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea.
authors.forename: Seung Hoon
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea.
authors.forename: Soon Young
authors.initials: SY
authors.lastname: Kwon
authors.affiliation: Laboratory of Neurodevelopmental Genetics, Graduate School of Medicine, Korea University, Seoul, Korea.
authors.forename: Hae-Chul
authors.initials: HC
authors.lastname: Park
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea.
authors.forename: Sung Won
authors.initials: SW
authors.lastname: Chae
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea.
authors.forename: Hak Hyun
authors.initials: HH
authors.lastname: Jung
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001681:Biological Assay; D002452:Cell Count; D004195:Disease Models, Animal; D006198:Hair Cells, Auditory / Q000187:drug effects / Q000473:pathology* / Q000648:ultrastructure; D020287:In Situ Nick-End Labeling; D053403:Lateral Line System / Q000187:drug effects / Q000473:pathology / Q000648:ultrastructure; D008856:Microscopy, Fluorescence; D009355:Neomycin; D009474:Neurons / Q000166:cytology / Q000187:drug effects; D020011:Protective Agents / Q000494:pharmacology*; D018038:Sodium Selenite / Q000494:pharmacology*; D015027:Zebrafish / Q000254:growth & development
chemical_list: D020011:Protective Agents; D018038:Sodium Selenite; D009355:Neomycin