title: Apoptosis-inducing factor is involved in gentamicin-induced vestibular hair cell death.
abstract: OBJECTIVE
  Vestibular hair cell loss in response to different stimuli may be attributable to the occurrence of apoptosis, in which apoptosis-inducing factor (AIF) is an important regulator mediating apoptotic process independent of caspases. This study was designed to investigate the possible involvement of AIF in gentamicin (GM)-induced vestibular hair cell death.
  
  
  METHODS
  Vestibular organs from postnatal day 3 or 4 rats were maintained in tissue culture and were exposed to 2 mg/ml GM for up to 72 h. Vestibular hair cell viability was quantified by MTT assay. Apoptosis was determined by flow cytometry. AIF activation was examined by RT-PCR. The expressions of the mitochondrial protein and cytoplasm protein of AIF were detected by Western blot.
  
  
  RESULTS
  GM could significantly inhibit the cell viability of vestibular hair cells in a dose- and time-dependent manner. The number of apoptotic cells treated with GM was higher than that of cells not treated with GM. RT-PCR showed upregulation of AIF mRNA under GM. Western blot showed that AIF from mitochondria was decreased, whereas AIF from cytoplasm was increased after GM exposure.
  
  
  CONCLUSIONS
  AIF participates in GM-induced apoptosis of vestibular hair cells.
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, Provincial Hospital affiliated to Shandong University, Jinan, PR China.
authors.forename: Daogong
authors.initials: D
authors.lastname: Zhang
authors.forename: Zhaomin
authors.initials: Z
authors.lastname: Fan
authors.forename: Yuechen
authors.initials: Y
authors.lastname: Han
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Bai
authors.forename: Wenwen
authors.initials: W
authors.lastname: Liu
authors.forename: Sumei
authors.initials: S
authors.lastname: Lu
authors.forename: Mingming
authors.initials: M
authors.lastname: Wang
authors.forename: Lei
authors.initials: L
authors.lastname: Xu
authors.forename: Jianfen
authors.initials: J
authors.lastname: Luo
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Li
authors.forename: Haibo
authors.initials: H
authors.lastname: Wang
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D051033:Apoptosis Inducing Factor / Q000096:biosynthesis / Q000235:genetics*; D015153:Blotting, Western; D002470:Cell Survival; D002478:Cells, Cultured; D004195:Disease Models, Animal; D005434:Flow Cytometry; D018507:Gene Expression Regulation, Developmental; D005839:Gentamicins / Q000633:toxicity; D018069:Hair Cells, Vestibular / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D012333:RNA, Messenger / Q000235:genetics*; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction; D014722:Vestibule, Labyrinth / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*
chemical_list: D051033:Apoptosis Inducing Factor; D005839:Gentamicins; D012333:RNA, Messenger