title: Effects of titanium dioxide nanoparticles isolated from confectionery products on the metabolic stress pathway in human lung fibroblast cells.
abstract: Titanium dioxide (TiO2) is a common additive in many foods, pigments, personal care products, and other consumer products used in daily life. Despite the widespread use of nanoscale TiO2 and composites of nanoscale TiO2 in the food industry, there is a serious lack of awareness of the toxicity of TiO2 nanoparticles (NPs) among consumers and manufacturers. There is an urgent need for toxicological studies of TiO2 NPs. TiO2 food additives separated from marketed foods were characterized by transmission electron microscopy. In addition, the effects of TiO2 NPs on metabolic stress in WI-38 cells were analyzed. Cell viability, total ROS, mitochondrial transmembrane potential (ΔψM), cell cycle, and metabolism-related gene expression were analyzed. The results indicate that TiO2 NPs have a significant concentration-dependent toxic effect in lung cells. The ΔψM, the intracellular ROS level, and the stages of the WI-38 cell cycle were altered by increasing TiO2 concentrations after exposure for 24 and 48 h relative to the control. Cytochrome P450 1A, GSTM3, and glutathione S-transferase A4 upregulation in response to the TiO2 NPs was observed. These findings suggest that the toxicity of TiO2 from confectionery products in WI-38 cells may be mediated through an increase in oxidative stress. The results of this study clearly demonstrate the nanotoxicological effects of TiO2 on WI-38 cells and will be useful for nanotoxicological indexing.
authors.affiliation: Nanobiotechnology and Molecular Biology Research Laboratory, Department of Food Science and Nutrition, College of Food Science and Agriculture, King Saud University, P.O. Box 2460, Riyadh, 11451, Kingdom of Saudi Arabia.
authors.forename: Vaiyapuri Subbarayan
authors.initials: VS
authors.lastname: Periasamy
authors.forename: Jegan
authors.initials: J
authors.lastname: Athinarayanan
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Al-Hadi
authors.forename: Fahad Al
authors.initials: FA
authors.lastname: Juhaimi
authors.forename: Ali A
authors.initials: AA
authors.lastname: Alshatwi
mesh_terms: D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003296:Cooking; D005347:Fibroblasts / Q000187:drug effects; D005506:Food Contamination / Q000032:analysis*; D006801:Humans; D008168:Lung / Q000187:drug effects; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D053768:Metal Nanoparticles / Q000633:toxicity*; D046529:Microscopy, Electron, Transmission; D017382:Reactive Oxygen Species; D013312:Stress, Physiological; D014025:Titanium / Q000633:toxicity*
chemical_list: D017382:Reactive Oxygen Species; C009495:titanium dioxide; D014025:Titanium