title: Cytotoxicity and genotoxicity in liver cells induced by cobalt nanoparticles and ions.
abstract: OBJECTIVE
  The cytotoxicity induced by cobalt ions (Co2+) and cobalt nanoparticles (Co-NPs) which released following the insertion of a total hip prosthesis, has been reported. However, little is known about the underlying mechanisms. In this study, we investigate the toxic effect of Co2+and Co-NPs on liver cells, and explain further the potential mechanisms.
  
  
  METHODS
  Co-NPs were characterised for size, shape, elemental analysis, and hydrodynamic diameter, and were assessed by Transmission Electron Microscope, Scanning Electron Microscope, Energy Dispersive X-ray Spectroscopy and Dynamic Light Scattering. BRL-3A cells were used in this study. Cytotoxicity was evaluated by MTT and lactate dehydrogenase release assay. In order to clarify the potential mechanisms, reactive oxygen species, Bax/Bcl-2 mRNA expression, IL-8 mRNA expression and DNA damage were assessed on BRL-3A cells after Co2+or Co-NPs treatment.
  
  
  RESULTS
  Results showed cytotoxic effects of Co2+and Co-NPs were dependent upon time and dosage, and the cytotoxicity of Co-NPs was greater than that of Co2+. In addition, Co-NPs elicited a significant (p < 0.05) reduction in cell viability with a concomitant increase in lactic dehydrogenase release, reactive oxygen species generation, IL-8 mRNA expression, Bax/Bcl-2 mRNA expression and DNA damage after 24 hours of exposure.
  
  
  CONCLUSIONS
  Co-NPs induced greater cytotoxicity and genotoxicity in BRL-3A cells than Co2+. Cell membrane damage, oxidative stress, immune inflammation and DNA damage may play an important role in the effects of Co-NPs on liver cells.Cite this article: Y. K. Liu, X. X. Deng, H.L. Yang. Cytotoxicity and genotoxicity in liver cells induced by cobalt nanoparticles and ions. Bone Joint Res 2016;5:461-469. DOI: 10.1302/2046-3758.510.BJR-2016-0016.R1.
authors.affiliation: Department of Orthopaedics, The Affiliated Hospital to Soochow University, Jiangsu, China.
authors.forename: Y K
authors.initials: YK
authors.lastname: Liu
authors.affiliation: Department of Orthopaedics, The Affiliated Hospital to Soochow University, Jiangsu, China.
authors.forename: X X
authors.initials: XX
authors.lastname: Deng
authors.affiliation: The Affiliated Hospital to Nantong University, Jiangsu, China yanghuilin912@163.com.
authors.forename: H L
authors.initials: HL
authors.lastname: Yang
keywords: Co-NPs; Cytotoxicity; DNA damage; Oxidative stress