Copper oxide nanoparticle toxicity profiling using untargeted metabolomics.
The rapidly increasing number of engineered nanoparticles (NPs), and products containing NPs, raises concerns for human exposure and safety. With this increasing, and ever changing, catalogue of NPs it is becoming more difficult to adequately assess the toxic potential of new materials in a timely fashion. It is therefore important to develop methods which can provide high-throughput screening of biological responses. The use of omics technologies, including metabolomics, can play a vital role in this process by providing relatively fast, comprehensive, and cost-effective assessment of cellular responses. These techniques thus provide the opportunity to identify specific toxicity pathways and to generate hypotheses on how to reduce or abolish toxicity.



We have used untargeted metabolome analysis to determine differentially expressed metabolites in human lung epithelial cells (A549) exposed to copper oxide nanoparticles (CuO NPs). Toxicity hypotheses were then generated based on the affected pathways, and critically tested using more conventional biochemical and cellular assays. CuO NPs induced regulation of metabolites involved in oxidative stress, hypertonic stress, and apoptosis. The involvement of oxidative stress was clarified more easily than apoptosis, which involved control experiments to confirm specific metabolites that could be used as standard markers for apoptosis; based on this we tentatively propose methylnicotinamide as a generic metabolic marker for apoptosis.



Our findings are well aligned with the current literature on CuO NP toxicity. We thus believe that untargeted metabolomics profiling is a suitable tool for NP toxicity screening and hypothesis generation.
Department of Molecular Biology, Division of Allergy and Immunology, University of Salzburg, Hellbrunner Strasse 34, 5020, Salzburg, Austria.
Matthew S P
MS
Boyles
Department of Molecular Biology, Division of Chemistry and Bioanalytics, University of Salzburg, Hellbrunner Strasse 34, 5020, Salzburg, Austria.
Christina
C
Ranninger
Department of Molecular Biology, Division of Chemistry and Bioanalytics, University of Salzburg, Hellbrunner Strasse 34, 5020, Salzburg, Austria.
Roland
R
Reischl
Center for Bioinformatics, University of Tübingen, Tübingen, Germany.|Department of Computer Science, University of Tübingen, Sand 14, 72076, Tübingen, Germany.
Marc
M
Rurik
Faculty of Geo- and Atmospheric Science, Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, 6020, Innsbruck, Austria.
Richard
R
Tessadri
Center for Bioinformatics, University of Tübingen, Tübingen, Germany.|Department of Computer Science, University of Tübingen, Sand 14, 72076, Tübingen, Germany.|Quantitative Biology Center, University of Tübingen, Auf der Morgenstelle 10, 72076, Tübingen, Germany.|Faculty of Medicine, University of Tübingen, Geissweg 3, 72076, Tübingen, Germany.|Max Planck Institute for Developmental Biology, Spemannstraße 35, 72076, Tübingen, Germany.
Oliver
O
Kohlbacher
Department of Molecular Biology, Division of Allergy and Immunology, University of Salzburg, Hellbrunner Strasse 34, 5020, Salzburg, Austria. albert.duschl@sbg.ac.at.
Albert
A
Duschl
Department of Molecular Biology, Division of Chemistry and Bioanalytics, University of Salzburg, Hellbrunner Strasse 34, 5020, Salzburg, Austria. c.huber@sbg.ac.at.
Christian G
CG
Huber
D017209:Apoptosis; D015415:Biomarkers / Q000378:metabolism; D045744:Cell Line, Tumor; D005979:Glutathione Peroxidase / Q000378:metabolism; D051547:Heme Oxygenase-1 / Q000378:metabolism; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism; D008175:Lung Neoplasms / Q000378:metabolism / Q000473:pathology; D055432:Metabolomics; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D046529:Microscopy, Electron, Transmission; D018384:Oxidative Stress; D000094765:Glutathione Peroxidase GPX1
D015415:Biomarkers; D016209:Interleukin-8; D005979:Glutathione Peroxidase; D051547:Heme Oxygenase-1; D000094765:Glutathione Peroxidase GPX1; C000722067:GPX1 protein, human
Adverse outcome pathways; Apoptosis; Copper oxide nanoparticles; Oxidative stress; Toxicity profiling; Untargeted metabolomics