title: Protective effect of hypotaurine against oxidative stress-induced cytotoxicity in rat placental trophoblasts.
abstract: BACKGROUND
  Hypotaurine is a precursor of taurine and an antioxidant, and is concentrated in fetal plasma compared to maternal plasma. Hypotaurine is significantly decreased in fetal plasma of ezrin (Vil2) knock-out mice, and fetuses show intrauterine growth retardation. The aim of this study was to characterize the mechanism through which cellular hypotaurine level is maintained in placental trophoblasts, and the effect of hypotaurine on oxidative stress induced by hydrogen peroxide (H2O2).
  
  
  METHODS
  Hypotaurine transfer from extracellular fluid and antioxidant effect of hypotaurine were analyzed in rat placental trophoblast TR-TBT 18d-1 cells.
  
  
  RESULTS
  We found that hypotaurine is concentrated into rat placental trophoblast TR-TBT 18d-1 cells, and the level of hypotaurine was markedly reduced by culture in medium supplemented with dialyzed fetal bovine serum (FBS) instead of normal FBS. The hypotaurine level recovered almost completely when hypotaurine was added to the culture medium, indicating that intracellular hypotaurine is predominantly supplied by transport across the plasma membrane from extracellular fluid rather than by biosynthesis. Hypotaurine showed a cytoprotective effect against H2O2-induced oxidative damage in TR-TBT 18d-1 cells. Hypotaurine treatment of TR-TBT 18d-1 cells increased antioxidant capacity against hydroxyl radical and peroxyl radical. The concentration of intracellular hydroxyl radical induced by H2O2 in TR-TBT 18d-1 cells was significantly reduced by hypotaurine treatment.
  
  
  CONCLUSIONS
  These results indicate that intracellular hypotaurine is mainly supplied to placental trophoblasts by transfer from extracellular fluid across the plasma membrane, and may play a role in cell protection by scavenging reactive oxygen species.
authors: Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan.
authors: T
authors: T
authors: Nishimura
authors: Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan.
authors: M
authors: M
authors: Duereh
authors: Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan.
authors: Y
authors: Y
authors: Sugita
authors: Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan.
authors: Y
authors: Y
authors: Yoshida
authors: Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan; School of Pharmaceutical Sciences, Teikyo University, Itabashi-ku, Tokyo 173-8605, Japan.
authors: K
authors: K
authors: Higuchi
authors: Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan. Electronic address: tomi-ms@pha.keio.ac.jp.
authors: M
authors: M
authors: Tomi
authors: Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan.
authors: E
authors: E
authors: Nakashima
mesh_terms: D000818:Animals; D005260:Female; D006861:Hydrogen Peroxide / Q000494:pharmacology; D018345:Mice, Knockout; D018384:Oxidative Stress / Q000187:drug effects*; D010920:Placenta / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D011247:Pregnancy; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D013654:Taurine / Q000031:analogs & derivatives* / Q000494:pharmacology; D014327:Trophoblasts / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology
chemical_list: D017382:Reactive Oxygen Species; D013654:Taurine; C003949:hypotaurine; D006861:Hydrogen Peroxide
keywords: Hypotaurine; Oxidative stress; Placenta; Reactive oxygen species; Transporter; Trophoblasts