title: Protection against copper-induced cytotoxicity by inclusion of gold.
abstract: BACKGROUND
  We previously reported that contact with copper (Cu) induced immediate cell death via an oxidation-involved mechanism, and the Cu-induced oxidation and cell death were effectively alleviated under hypoxic conditions. In order to explore alternative strategies for the protection from the Cu-induced cytotoxicity, we investigated whether the inclusion of gold (Au) in the Cu plate, as alloy,has a protective effect.
  
  
  METHODS
  Human gingival fibroblast (HGF) cells, established from periodontal tissues, were inoculated on Au/Cu alloy of different Au ratios. After incubation at 37°C for different times under normoxic conditions, cellular viability and amino acid consumption were determined. Changes in the elemental composition of the alloy and in the culture medium were chemically analyzed by X-ray photoelectron spectroscopy and by inductively coupled plasma-optical emission spectrometry.
  
  
  RESULTS
  Contact with the Cu plate induced cytotoxicity and cystine oxidation in time-dependent manners. Inclusion of Au at more than 10% in the alloy, completely abrogated the cytotoxicity and reduced the oxidation of Cu and the elution of Cu from the alloy.
  
  
  CONCLUSIONS
  Inclusion of Au as a component of alloy reduces the cytotoxicity of the Cu plate, possibly by reducing its oxidation.
authors: Meikai University School of Dentistry, Sakado, Saitama 350-0283, Japan.
authors: Takashi
authors: T
authors: Yamazaki
authors: Masahiko
authors: M
authors: Kobayashi
authors: Kumi
authors: K
authors: Hirano
authors: Hiroyuki
authors: H
authors: Onuki
authors: Jun
authors: J
authors: Shimada
authors: Atsushi
authors: A
authors: Yamazaki
authors: Yasushi
authors: Y
authors: Hibino
authors: Hiroshi
authors: H
authors: Nakajima
authors: Yoshiko
authors: Y
authors: Yokote
authors: Shinji
authors: S
authors: Takemoto
authors: Yutaka
authors: Y
authors: Oda
authors: Hiroshi
authors: H
authors: Sakagami
mesh_terms: D002478:Cells, Cultured; D003300:Copper / Q000633:toxicity*; D004336:Drug Antagonism; D006046:Gold / Q000737:chemistry*; D006801:Humans; D010084:Oxidation-Reduction; D013499:Surface Properties
chemical_list: D006046:Gold; D003300:Copper