title: Effect of silver, copper, mercury, and nickel ions on cellular proliferation during extended, low-dose exposures.
abstract: Previous studies have demonstrated and quantified the cytotoxicity of metal ions in vitro, but the data from these reports have been limited to short-term exposures of metal ions to cells (24-72 h). Yet, the longer-term, low-dose effects of metal ions are most relevant to the clinical use of dental and other biomedical alloys. Thus, the purpose of the current study was to assess longer-term effects of ions of silver, copper, mercury, and nickel - four metal ions known to be released from dental alloys - on monocytes. THP-1 human monocytes were exposed to the metal ions for up to 4 weeks. Concentrations of the metal ions were 1-10% of those known to cause cytotoxicity with 24-h exposures. Cellular proliferation and cellular viability were measured weekly. Ag(1+) and Hg(2+) did not alter the percentage of nonviable cells, but Cu(2+) and Ni(2+) increased the nonviable component as a function of metal concentration. These effects were cumulative over the 4 weeks only for Ni(2+). All metal ions caused a significant reduction in cellular proliferation, but the pattern of the effect was unique to each metal ion, and the effects were often not evident until 3 or 4 weeks of exposure. The results of the current study indicate that metal ions released from metallic biomaterials may have adverse biological effects at concentrations lower than previously reported.
authors.affiliation: Department of Oral Rehabilitation, Medical College of Georgia School of Dentistry, Augusta, Georgia 30912-1260, USA. watahaj@mail.mcg.edu
authors.forename: J C
authors.initials: JC
authors.lastname: Wataha
authors.forename: P E
authors.initials: PE
authors.lastname: Lockwood
authors.forename: A
authors.initials: A
authors.lastname: Schedle
mesh_terms: D001672:Biocompatible Materials / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D003300:Copper / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008628:Mercury / Q000494:pharmacology*; D009000:Monocytes / Q000166:cytology* / Q000187:drug effects*; D009532:Nickel / Q000494:pharmacology*; D012834:Silver / Q000494:pharmacology*
chemical_list: D001672:Biocompatible Materials; D012834:Silver; D003300:Copper; D009532:Nickel; D008628:Mercury