Structural and biochemical modifications of model and native membranes of human immune cells in response to the action of zinc oxide nanoparticles

Abstract

The development of nanotechnology has led to the increased production of zinc oxide nanoparticles (ZnO‐NPs) and their application in a wide variety of everyday products. It creates the need for a full assessment of their safety for humans. The aim of the study was to assess the toxic effects of ZnO‐NPs on model human cells of the immune system: U‐937, HL‐60, HUT‐78, and COLO‐720L. Particular attention was paid to the direct interaction of the nanoparticles with membrane lipids and the role of zinc ions in the mechanism of their toxicity. Cell viability, lipid peroxidation, cell membrane integrity, and the amount of zinc ions released from nanoparticles were tested. Disruption in cell metabolism was noted for ZnO‐NPs concentrations from 6.25 mg/L. Contact with ZnO‐NPs caused lipid peroxidation of all cells and correlated with membrane disruption of HL‐60, HUT‐78, and COLO‐720L cells. Model monolayers (Langmuir technique) were used to assess the interaction of the nanoparticles with the studied lipids. Physicochemical parameters, such as the area per molecule at maximal layer compression, the pressure at which the monolayer collapses, and the static compression modulus, were calculated. The models of the HL‐60 and U‐937 cell membranes under ZnO‐NPs treatment reacted in a different way. It has also been shown that Zn2+ are not the main causative factor of ZnO‐NPs toxicity. Investigating the early stages of mechanism of nanoparticles toxicity will allow for a more complete risk assessment and development of methods for a safer synthesis of engineering nanomaterials.

Effects of 3FTx Protein Fraction from Naja ashei Venom on the Model and Native Membranes: Recognition and Implications for the Mechanisms of Toxicity

“…A mixture consisting of pure phospholipids, reflecting the composition of the natural membranes HL-60 and U-937, was adopted as the control system. The shapes of these isotherms are typical for the studied models and can be found in the literature [28]. Previous studies performed on the HL-60 and U-937 cell lines suggested a higher sensitivity, identified for HL-60 line, in contrast to the U-937 line.…”

Cytotoxicity of zinc oxide nanoparticles to innate and adaptive human immune cells

“…The concentration of ZnO‐NPs in the body will be lower than the concentration at the point of contact. Therefore, the amounts applied for the present studies were much lower than those usually used in industry (Czyzowska, Dyba, Rudolphi‐Szydło, & Barbasz, 2020). That is why the results show a real threat not only associated with the use of products containing ZnO‐NPs but primarily with work in their production (Lu, Huang, Chen, Chiueh, & Shih, 2015; Ruszkiewicz et al, 2017).…”

“…However, they suggest that although intracellular growth of ROS level correlates with cell viability, it was not a major factor in the cytotoxicity of ZnO particles, but only the response of cells to mitochondrial damage induced by zinc ions and ZnO particles. However, in our previous work, we showed that zinc ions are not the main factor causing the toxicity of zinc oxide nanoparticles toward cells of the immune system (Czyżowska et al, 2020).…”

The cell membrane as the barrier in the defense against nanoxenobiotics: Zinc oxide nanoparticles interactions with native and model membrane of melanoma cells

“…We presented the physicochemical characteristics in ultrapure water, phosphate‐buffered saline (PBS), and complete cell culture medium, of selected NPs earlier (Czyżowska et al, 2020).…”

“…Previously, we showed that commercial ZnO‐NPs are toxic to human immune cells, and the mechanism of their toxicity is related to the change in the composition and structure of the membranes of the studied cells (Czyżowska & Barbasz, 2020b; Czyżowska et al, 2020).…”