Poorly soluble cobalt oxide particles trigger genotoxicity via multiple pathways.

Background: Poorly soluble cobalt (II, III) oxide particles (Co3O4P) are believed to induce in vitro cytotoxic effects via a Trojan-horse mechanism. Once internalized into lysosomal and acidic intracellular compartments, Co3O4P slowly release a low amount of cobalt ions (Co(2+)) that impair the viability of in vitro cultures. In this study, we focused on the genotoxic potential of Co3O4P by performing a comprehensive investigation of the DNA damage exerted in BEAS-2B human bronchial epithelial cells.

Low-solubility particles and a Trojan-horse type mechanism of toxicity: the case of cobalt oxide on human lung cells.

Background: The mechanisms of toxicity of metal oxide particles towards lung cells are far from being understood. In particular, the relative contribution of intracellular particulate versus solubilized fractions is rarely considered as it is very challenging to assess, especially for low-solubility particles such as cobalt oxide (Co3O4).

Methods: This study was possible owing to two highly sensitive, independent, analytical techniques, based on single-cell analysis, using ion beam microanalysis, and on bulk analysis of cell lysates, using mass spectrometry.

In vitro assessment of cobalt oxide particle toxicity: identifying and circumventing interference.

The continuing development of nanotechnology necessitates the reliable assessment of potential adverse health consequences associated with human exposures. The physicochemical properties of nanomaterials can be responsible for unexpected interactions with components of classical toxicity assays, which may generate erroneous interpretations. In this paper, we describe how particle interference can be observed in in vitro toxicity tests (CellTiter Blue, CyQUANT, WST-1 and CellTiter-Glo assay) and in cell biology tests using flow cytometry (cell cycle analysis).

Cobalt chloride speciation, mechanisms of cytotoxicity on human pulmonary cells, and synergistic toxicity with zinc.

Cobalt is used in numerous industrial sectors, leading to occupational diseases, particularly by inhalation. Cobalt-associated mechanisms of toxicity are far from being understood and information that could improve knowledge in this area is required. We investigated the impact of a soluble cobalt compound, CoCl(2)·6H(2)O, on the BEAS-2B lung epithelial cell line, as well as its impact on metal homeostasis.

Analytical constraints for the analysis of human cell line secretomes by shotgun proteomics.

Human cell line secretome represents a valuable source of therapeutic targets and candidate biomarkers. Secreted proteins found in biological fluids or culture media are by essence highly diluted. Secretome investigation with proteomic approaches is hardly compatible with the high content of proteins found in complete cell culture media.