Abstract
Background: Gold nanoparticles (AuNPs), a new cancer treatment, have few side effects. Objectives: This study aimed to investigate the effect of AuNPs on oxidative stress in HCT-116 colon cancer cells. Methods: The viability of HCT-116 cells was evaluated using the 3-(4,5-dimethylthiazol-2,5-diphenyl) tetrazolium bromide (MTT) assay after 24 and 48 hours of incubation with different concentrations of AuNPs (0 - 50 μg/mL). The state of oxidative stress, total antioxidant capacity (TAC), total oxidative status (TOS), reactive oxygen species (ROS) levels, and the activity of antioxidant enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT), were determined by colorimetric and fluorometric methods. Results: Oxidative stress parameters and ROS were significantly increased in cells treated with 25 and 50 μg/mL concentrations of AuNPs during 24 and 48 hours of incubation compared to control cells (P < 0.001). In contrast, the level of TAC and the activity of antioxidant enzymes SOD, GPX, and CAT were significantly decreased in the treated groups compared to the untreated cells after 48 hours of incubation (P < 0.05). Conclusions: This study showed that AuNPs affect HCT-116 cancer cells by increasing ROS and oxidative stress while reducing the activity of antioxidant enzymes.