Relationship between lymphocyte DNA fragmentation and dose of iron oxide (Fe₂O₃) and silicon oxide (SiO₂)...

At present, the use of nanoparticles is a controversial topic, especially when analyzing their effects in human tissues. Nanoparticles (NPs) can cause oxidative stress by increasing membrane lipids peroxidation and reactive oxygen species, and decreasing intracellular glutathione. Oxidative stress plays an important role in cell signaling and inflammatory responses. It can result in genotoxicity, affect cell proliferation, and induce DNA damage. The objective of this study is to evaluate the genotoxic potential of NPs in lymphocyte DNA. Wistar female rats (N = 45) were sorted in three randomized groups as follows: Group 1 (N = 20); Group 2 (N = 20) and a control group (N = 5). A single dose of iron oxide (Fe₂O₃) and silicon oxide (SiO₂) NPs dissolved in saline solution were administered orally to the rats. Cardiac puncture was performed to extract peripheral blood for genotoxic analysis. DNA fragmentation for lymphocytes was performed. Control rats showed a fragmentation percentage of 11.20 ± 2.16%. Rats exposed to SiO₂ and Fe₂O₃ NPs for 24 h showed statistically significant differences in DNA fragmentation percentages as compared with that of the control group. A lineal dose-response correlation between genotoxic damage and exposure to SiO₂ and Fe₂O₃ NPs was found (r² = 0.99 and 0.98 for SiO₂ and Fe₂O₃, respectively). In conclusion, we found that exposure to Fe₂O₃ and SiO₂ NPs can cause DNA fragmentation in lymphocytes in a dose-dependent manner.