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.
