Folia Biologica
Journal of Cellular and Molecular Biology, Charles University 

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Fol. Biol. 2015, 61, 33-42

https://doi.org/10.14712/fb2015061010033

Manufactured Silver Nanoparticles of Different Sizes Induced DNA Strand Breaks and Oxidative DNA Damage in Hepatoma and Leukaemia Cells and in Dermal and Pulmonary Fibroblasts

A. Ávalos, A. I. Haza, Paloma Morales

Departamento de Nutrición, Bromatología y Tecnología de los Alimentos. Facultad de Veterinaria, Universidad Complutense de Madrid, Spain

Received July 2014
Accepted November 2014

Many classes of silver nanoparticles (AgNPs) have been synthesized and widely applied, but no conclusive information on their potential cytotoxicity and genotoxicity mechanisms is available. Therefore, the purpose of this study was to compare the potential genotoxic effects (DNA strand breaks and oxidative DNA damage) of 4.7 nm coated and 42 nm uncoated AgNPs, using the comet assay, in four relevant human cell lines (hepatoma, leukaemia, and dermal and pulmonary fibroblasts) in order to understand the impact of such nanomaterials on cellular DNA. The results indicated that in all cell lines tested, 4.7 nm coated (0.1–1.6 μg ml-1) and 42 nm uncoated (0.1–6.7 μg ml-1) AgNPs increased DNA strand breaks in a dose- and size-dependent manner following 24 h treatment, the smaller AgNPs being more genotoxic. Human pulmonary fibroblasts showed the highest sensitivity to the AgNPs. A modified comet assay using endonuclease III and formamidopyrimidine- DNA glycosylase restriction enzymes showed that in tumoral and normal human dermal fibroblasts, pyrimidines and purines were oxidatively damaged by both AgNPs, but the damage was not size-dependent. However, in human pulmonary fibroblasts, no oxidative damage was observed after treatment with 42 nm AgNPs. In conclusion, both AgNP sizes induced DNA damage in human cells, and this damage could be related to oxidative stress.

Funding

This work has been supported by Grant AGL2010-16561 from the Ministerio de Educación, Cultura y Deporte (Spain). A. Ávalos is a recipient of a fellowship from the Ministerio de Educación, Cultura y Deporte, Spain.

References

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