Titanium Dioxide (Tio2) Nanoparticles Induced ROS Generation and its Effect on Cellular Antioxidant Defense in WRL-68 Cell
MOJ Bioequivalence & Bioavailability
Abbreviations: ROS, reactive oxygen species; DNA, deoxyribonucleic acid, NRU, national research universal; MSP, methylation specific polymerase chain reaction Abstract The nanosized titanium dioxide (nano-TiO 2 ) is produced abundantly and used widely in the chemical, electrical/electronic and energy industries because of its special photovoltaic and photocatalytic activities. Previous reports have shown that the nano-TIO 2 can enter into the human body through different routes such as
... es such as inhalation, ingestion, dermal penetration and injection. The effects of nano-TIO 2 on different organs are being investigated and the concerns on its large scale applications such as sunscreen, etc. In this study, the cytotoxicity of the nano-TIO 2 was investigated in WRL-68 cells. The human hepatic cell line (WRL-68) was used to evaluate molecular mechanism involved for toxic effect of TIO 2 NPs. The uptake of TIO 2 NPs in WRL-68 cells was monitored by measuring SSC intensity with maximum at 1000μM. The ROS generated at concentration 1000μM of TIO 2 NPs in WRL-68 cells was 125.12 %. Moreover, ROS induced methylation of CpG island II on the catalase promoter and down regulated catalase expression at the transcriptional level in WRL-68 cell. Subsequently, proliferation of WRL-68 cells was increased on exposure to TIO 2 NPs as demonstrated by MTT and NRU assay. Conclusively, it is demonstrated that exposure of TIO 2 NPs at 1000μM for 24h in WRL-68 cell induced methylation of CpG island II via ROS on the catalase promoter and downregulated catalase expression at the transcriptional level.