Differential toxicity of copper (II) oxide nanoparticles of similar hydrodynamic diameter on human differentiated intestinal Caco-2 cell monolayers is correlated in part to copper release and shape

Abstract

The potential toxic effects of copper oxide (CuO) nanoparticles (NPs) were studied on differentiated Caco-2 cell monolayers, a classical in vitro model of human small intestine epithelium. Two types of CuO NPs, with different specific surface area, different sizes as raw material but the same hydrodynamic diameter in suspension, differentially disturbed the monolayer integrity, were cytotoxic and triggered an increase of the abundance of several transcripts coding for pro-inflammatory cytokines and chemokines. Specific surface area was not a major variable explaining the increased toxicity when intestinal epithelium is exposed to rod-shaped CuO NPs, compared with spherical CuO NPs. The results suggest that release of Cu(II) cations and shape of these CuO NPs are likely to be implicated in the toxicity of these CuO NPs.

Keywords::

• Copper
• shape
• toxicity
• specific surface area

Acknowledgements

We acknowledge the “Direction Générale Opérationnelle de l'Economie, de l'Emploi et de la Recherche” (DGO6) of the Public Service of Wallonia (SPW) for the ‘Nanotoxico’ Excellence Pole of Research, convention # 516252. This work was also supported by Silicalloy project, RW/FUNDP research convention no. 6144. O. Toussaint is a Senior Research Associate of the Belgian FNRS. E. Boilan was a fellow of the Belgian FRIA.