Nanomaterials induce different levels of oxidative stress, depending on the used model system: Comparison of in vitro and in vivo effects

Abstract

Background: The immense variety and constant development of nanomaterials (NMs) raise the demand for a facilitated risk assessment, for which knowledge on NMs mode of actions (MoAs) is required. For this purpose, a comprehensive data basis is of paramountcy that can be obtained using omics. Furthermore, the establishment of suitable in vitro test systems is indispensable to follow the 3R concept and to master the high number of NMs. In the present study, we aimed at comparing NM effects in vitro and in vivo using a multi-omics approach. We applied an integrated data evaluation strategy based on proteomics and metabolomics to four silica NMs and one titanium dioxide-based NM. For in vitro investigations, rat alveolar epithelial cells (RLE-6TN) and rat alveolar macrophages (NR8383) were treated with different doses of NMs, and the results were compared to effects on rat lungs after shortterm inhalations and instillations at varying doses with and without a recovery period.Results: Since the production of reactive oxygen species (ROS) is described to be a critical biological effect of NMs, and enrichment analyses con rmed oxidative stress as a signi cant effect upon NM treatment in vitro in the present study, we focused on different levels of oxidative stress. Thus, we found opposite changes for proteins and metabolites that are related to the production of reduced glutathione in alveolar epithelial cells and alveolar macrophages, illustrating that NMs MoAs depend on the used model system. Interestingly, in vivo, pathways related to in ammation were affected to a greater extent than oxidative stress responses. Hence, the assignment of the observed effects to the levels of oxidative stress was different in vitro and in vivo as well. However, the overall classi cation of "active" and "passive" NMs was consistent in vitro and in vivo.Conclusions: The consistent classi cation indicates both tested cell lines to be suitable for NM toxicity assessment even though the induced levels of oxidative stress strongly depend on the used model systems. Thus, the here presented results highlight that model systems need to be carefully revised to decipher the extent to which they can replace in vivo testing.

Study on the biological effects of ZnO nanosheets on EBL cells

“…Some studies have shown that nanomaterials interact with cell membranes to generate large amounts of ROS, which causes structural damage to the cell membranes and leads to the imbalance of the intracellular environment, resulting in cell apoptosis ( Król et al, 2017 ). Karkossa et al ( 2021 ) found that the production of ROS and oxidative stress responses are the main ways in which nanomaterials cause a variety of biological effects.…”

“…Some studies have shown that nanomaterials interact with cell membranes to generate large amounts of ROS, which causes structural damage to the cell membranes and leads to the imbalance of the intracellular environment, resulting in cell apoptosis (Król et al, 2017). Karkossa et al (2021) found that the production of ROS and oxidative stress responses are the main ways in which nanomaterials cause a variety of biological effects. In this study, the effects of ZnO nanosheets on the morphology of fetal bovine lung epithelial cells and the effects of cytotoxicity, intracellular reactive oxygen levels, and apoptosis were investigated in detail.…”

Predicting nanomaterials pulmonary toxicity in animals by cell culture models: Achievements and perspectives

“…With this setup, the in vitro responses predicted the inflammation in vivo with 95% concordance, 91% specificity, and a 100% sensitivity (Wiemann et al, 2016 ). Karkossa et al ( 2021 ) investigated a group of metal oxide nanomaterials that included four SiO 2 NMs and one TiO 2 . The authors tested with metabolomic and proteomic changes in the pathways involved in the oxidative stress in rat alveolar epithelial cells, macrophages, and rat lung.…”

“…The authors tested with metabolomic and proteomic changes in the pathways involved in the oxidative stress in rat alveolar epithelial cells, macrophages, and rat lung. The authors observed that the changes of markers were different in all the models; however, the classification of “active” or “passive,” based on significantly changed signatures in exposed groups compared with controls, led to the congruent classifications between in vitro and in vivo (Karkossa et al, 2021 ).…”

Succinate, silicon dioxide, aluminium oxide, and silver nano- and microparticle influence on the model organism Drosophila melanogaster

“…The effects of nanoparticles on living organisms are being studied both in plants (Gao et al, 2023, Grauda et al, 2015 and animals (Lama et al, 2020) using in vitro and in vivo systems. Nanoparticle effects depends on whether cells are studied in vitro or at organism level (Karkossa et al, 2021). It is convenient to use invertebrate models to assess the impact on the whole organism, as they are subjected to less ethical requirements.…”