Toxicity analysis of zinc oxide nanoparticles (ZnO-NP) in mesenchymal stem cells (MSC) after cultivation in blood plasma or cell culture medium

Nanomaterials are frequently used in the industrial procedures, biomedicine and research. ZnO-NP are among the most commonly used nanomaterials. Human exposure to NPs is achieved via the gastrointestinal tract, the skin and the airways. However, toxicological assessment of ZnO-NPs is divergent. The toxicological in vitro analyses are usually done under standard culture conditions with mediums supplemented with animal serum. The current study aims to investigate the toxicity of ZnO-NPs in MSC after cultivation with standard medium and 100% human blood plasma (BP).

BP was isolated from peripheral blood. DMEM plus 10% FCS (DMEM-EM) served as control. First, ZnO-NP were physically characterized. After cell exposure, detection of the particles was achieved by electronmicroscopy. Cyto- and genotoxicity were investigated by the MTT- and Comet-assay, respectively.

The proliferation of MSC was significantly enhanced after cultivation with BP compared to DMEN-EM. ZnO-NP could be detected in the cells by the electronmicroscopy. ZnO-NP concentration-dependent cyto- and genotoxicity was shown in MSC cultivated with DMEM-EM. After cultivation with BP toxicity was not observed.

Alteration of culture media had a neutralizing effect on cyto- and genotoxicity of ZnO-NP in MSC. One reason could be NP binding to plasma proteins resulting in decreased cellular uptake. Under these aspects, in vitro toxicological studies on NP must be seen critically, since NP exposure in BP reveals a higher in vivo correlation than in DMEM-EM.

Publication History

Publication Date:
23 April 2019 (online)