Mechanisms underlying the enhancement of toxicity caused by the coincubation of zinc oxide and copper nanoparticles in a fish hepatoma cell line

Abstract

Ecosystems are exposed to a wide variety of individual substances, including at the nano-scale; and the potential adverse effects of their interactions are an increasing concern. The purpose of the present study was to determine whether zinc oxide nanoparticles (ZnONPs) at a no-observed-effect concentration modulate the cytotoxicity of copper nanoparticles (CuNPs) in the fish hepatoma cell line PLHC-1 after 48 h of exposure and the contribution of the released ions to these effects. Cells were exposed to 50-nm CuNPs (0.39-25.0 µg/mL), alone or in combination with ZnONPs (25 nm or 100 nm), at 6.25 µg/mL. Cells were exposed to suspensions of NPs or to their supernatants, as well as to their combinations. The effects on cell viability were assessed through cytotoxicity assays. Changes in cell morphology and metal internalization were also evaluated. The cytotoxicity exerted by CuNPs was enhanced in the presence of nontoxic concentrations of ZnONPs. On the contrary, Zn ions protected the cell line from the CuNP toxicity, this effect being related to an increase in the intracellular levels of Zn. This increase of metal was not observed in cells exposed to both ZnONPs and CuNPs, even when they were visualized inside the cell. The results indicated that the internalization of ZnONPs, but not the Zn ions, was responsible for the enhanced toxicity of the CuNPs. Environ Toxicol Chem 2016;35:2562-2570. © 2016 SETAC.

Comparison of cytotoxicity of Ag/ZnO and Ag@ZnO nanocomplexes to human umbilical vein endothelial cells in vitro

“…Indeed, comparative studies suggested that Ag NPs were relatively less cytotoxic compared with ZnO NPs at the same mass concentrations (Elje et al, 2020; L. Jiang, Li, Xie, Liu, & Cao, 2019; Lee & Park, 2019; Wan et al, 2018), and therefore, adding Ag into ZnO nanocomplexes is expected to reduce the overall toxicity. This is also consistent with previous studies that showed that the presence of metal‐based NPs or metal ions alleviated the toxicity of other NPs (Hackenberg et al, 2017; Hernández‐Moreno et al, 2016; Hu, Hu, Li, & Zhao, 2016; Sun et al, 2020). However, we noticed that compared with soft materials such as liposomes (L. Shi, Wang, et al, 2020), polymers (Li et al, 2021; Zhou et al, 2020), chitosan (W. Han et al, 2019), lipids (Wan et al, 2018; Xie, Wan, Chen, Han, & Wang, 2020), soluble supramolecular NPs (X. Chen, Hu, et al, 2020), and proteins (An et al, 2020), the cytotoxicity of Ag–ZnO nanocomplexes was still relatively high.…”

Investigation on the Toxicity of Nanoparticle Mixture in Rainbow Trout Juveniles

“…The element Ti is more resistant to oxidation than Ce. In fish hepatoma cells, the effects of nZnO and nCuO mixture was enhanced and did not involve the mobilization of zinc ions [ 46 ]. The toxicity of nCuO was reduced when Zn 2+ was added to the incubation media leading to an increase in labile Zn in cells.…”

Exposure to copper nanoparticles induces oxidative stress and alters Hsp70 and Sod2 gene expression in Drosophila melanogaster

“…Copper nanoparticles (CuNPs) have received much interest due to their unique physicochemical properties and low fabrication cost [6] . CuNPs are extensively used in electronics and metallic inks due to their optical, electrical, catalytic, and antimicrobial properties [7][8][9] .…”