RESEARCH ARTICLE
Effect of Nickel Chloride on Cell Proliferation
Vincenzo D’Antò 1, Rosa Valletta 1, Massimo Amato 2, Helmut Schweikl 3, Michele Simeone 1, Sergio Paduano 4, Sandro Rengo 1, Gianrico Spagnuolo 1, *
Article Information
Identifiers and Pagination:
Year: 2012Volume: 6
First Page: 177
Last Page: 181
Publisher ID: TODENTJ-6-177
DOI: 10.2174/1874210601206010177
Article History:
Received Date: 11/9/2012Revision Received Date: 4/10/2012
Acceptance Date: 5/10/2012
Electronic publication date: 16/11/2012
Collection year: 2012

open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
Abstract
Objective:
Metal alloys used in dentistry and in other biomedical fields may release nickel ions in the oral environment. The release of nickel might influence the normal biological and physiological processes, including tissue wound healing, cell growth and proliferation. The aim of this study was to evaluate in vitro the effects of nickel ions on cell cycle, viability and proliferation.
Materials and Methods:
Human osteosarcoma cells (U2OS) and human keratinocytes (HaCat) were exposed to different nickel chloride (NiCl2) concentrations (0 - 5mM) for various periods exposure. The viability of cultured cells was estimated by flow cytometry using Annexin V-FITC and Propidium Iodide (PI). Cell proliferation was evaluated by using carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) and flow cytometry. Finally, the effects of NiCl2 on cell cycle were assessed and quantified by flow cytometry. Statistical analysis was performed by means of ANOVA followed by Tukey’s test.
Results:
NiCl2 induced a dose and time dependent decrease in cell viability. After 24h, 1mM NiCl2 caused a similar and significant reduction of viability in U2OS and HaCat cells, while higher NiCl2 concentrations and longer exposure times showed a reduced cytotoxic effect in HaCat as compared to U2OS cells.
Exposure to NiCl2 caused a dose- and time-dependent inhibition of cell proliferation in both cell lines tested, with a prominent effect on U2OS cells. Furthermore, both cell lines exposed to NiCl2 exhibited significant changes in cell cycle distribution after 24h exposure 2mM NiCl2, as compared to untreated cells (p<0.05).
Conclusion:
Our results indicate that release of nickel ions may affect cell proliferation. The inhibition of cell growth by NiCl2 is mediated by both cell cycle arrest and by induction of cell death.