title: Prosaposin-derived peptide alleviates ischaemia-induced hearing loss.
abstract: CONCLUSIONS
  An 18-mer peptide derived from the neurotrophic region of prosaposin (PS-pep) prevents hearing loss and cochlear damage due to transient cochlear ischaemia by activating an anti-apoptotic pathway. PS-pep is a potent candidate molecule for alleviating ischaemia-induced hearing loss.
  
  
  OBJECTIVE
  PS-pep was investigated for its protective effects against ischaemia-induced hearing loss and cochlear damage.
  
  
  METHODS
  Ischaemia was induced in both cochleae in Mongolian gerbils by pulling the ligatures around both vertebral arteries in an anterior direction using 5 g weights for 15 min. PS-pep was synthesized artificially and administered subcutaneously four times after the induction of transient cochlear ischaemia.
  
  
  RESULTS
  An increase in the auditory brainstem response threshold was alleviated in animals treated with 2.0 mg/kg PS-pep. Histological examinations conducted on day 7 showed that the loss of inner hair cells (IHCs) was more prominent than that of outer hair cells. Higher doses of PS-pep significantly alleviated IHC loss. An increase in the anti-apoptotic factor bcl-2 was also noted in the IHCs treated with PS-pep.
authors.affiliation: Department of Anatomy and Embryology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Takehiro
authors.initials: T
authors.lastname: Terashita
authors.forename: Shouichiro
authors.initials: S
authors.lastname: Saito
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Nabeka
authors.forename: Naohito
authors.initials: N
authors.lastname: Hato
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Wakisaka
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Shimokawa
authors.forename: Naoto
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Kiyofumi
authors.initials: K
authors.lastname: Gyo
authors.forename: Seiji
authors.initials: S
authors.lastname: Matsuda
mesh_terms: D000818:Animals; D003051:Cochlea / Q000098:blood supply*; D004195:Disease Models, Animal; D016057:Evoked Potentials, Auditory, Brain Stem; D005849:Gerbillinae; D034381:Hearing Loss / Q000188:drug therapy* / Q000209:etiology; D007511:Ischemia / Q000150:complications*; D009925:Organ of Corti / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D049231:Saposins / Q000138:chemical synthesis / Q000627:therapeutic use*
chemical_list: C483345:PSAP protein, human; D019253:Proto-Oncogene Proteins c-bcl-2; D049231:Saposins