DNA Oxidative Damage as a Sensitive Genetic Endpoint to Detect the Genotoxicity Induced by Titanium Dioxide Nanoparticles

Abstract

The genotoxicity of nanomaterials has attracted great attention in recent years. As a possible occupational carcinogen, the genotoxic effects and underlying mechanisms of titanium dioxide nanoparticles (TiO2 NPs) have been of particular concern. In this study, the effect of TiO2 NPs (0, 25, 50 and 100 µg/mL) on DNA damage and the role of oxidative stress were investigated using human bronchial epithelial cells (BEAS-2B) as an in vitro model. After detailed characterization, the cytotoxicity of TiO2 NPs was detected. Through transmission electron microscopy (TEM), we found that TiO2 NPs entered the cytoplasm but did not penetrate deep into the nucleus of cells. The intracellular levels of reactive oxygen species (ROS) significantly increased in a dose-dependent manner and the ratios of GSH/GSSG also significantly decreased. The results of the normal comet assay were negative, while the Fpg-modified comet assay that specifically detected DNA oxidative damage was positive. Meanwhile, N-acetyl-L-cysteine (NAC) intervention inhibited the oxidative stress and genotoxicity induced by TiO2 NPs. Therefore, it was suggested that TiO2 NPs could induce cytotoxicity, oxidative stress and DNA oxidative damage in BEAS-2B cells. DNA oxidative damage may be a more sensitive genetic endpoint to detect the genotoxicity of TiO2 NPs.

Coating effect of renatured triple-helix lentinan on the morphology and antimicrobial activity of ZnO synthesized by hydrothermal method

“…NAC is a commonly used antioxidant that has the effect of inhibiting oxidative stress. 37 It can be observed that the polysaccharide has a NAC-like function, and its addition leads to a reduction in ROS, but the antioxidant capacity is weak.…”

“…NAC is a commonly used antioxidant that has the effect of inhibiting oxidative stress. 37 It can be observed that the polysaccharide has a NAC-like function, and its addition leads to a reduction in ROS, but the antioxidant capacity is weak. Finally, ZnO/r-LNT-2, which exhibits the best inhibitory effect, was used to investigate its effect on the intracellular level of reactive oxygen species in Candida albicans.…”

The ROS mediates MCUb in mitochondria-regulated apoptosis of TM4 cells induced by titanium dioxide nanoparticles

“…These results are consistent with previous studies that have revealed that TiO 2 NPs induced increased levels of ROS, oxidative stress and DNA damage in various cells. These include human bronchial epithelial cells (BEAS-2B cells), colorectal carcinoma cells (Caco-2 cells) and hepatoma carcinoma cells (HepG2 cells) [33,34].…”

Nanoparticles: A Potential and Effective Method to Control Insect-Borne Diseases

“…Besides, the metal ions contained in the material enter the cell during the process of outward release and bind to the amino acids S and P in proteins, reducing cell membrane permeability [ 83 ]. Once inside cells, NPs may cause damage to DNA and inhibit the activity of intracellular enzymes [ 84 ]. Very recently, Chimkhan outlined that Ag NPs ingested by Bacillus thuringiensis led to mortality and detrimental effects on Aedes aegypti larvae.…”