1. Oxidative damage of lung and its protective mechanism in mice caused by long-term exposure to titanium dioxide nanoparticles.
- Author
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Sun Q, Tan D, Zhou Q, Liu X, Cheng Z, Liu G, Zhu M, Sang X, Gui S, Cheng J, Hu R, Tang M, and Hong F
- Subjects
- Alveolar Epithelial Cells drug effects, Alveolar Epithelial Cells pathology, Alveolar Epithelial Cells ultrastructure, Animals, Apoptosis drug effects, Female, Gene Expression Regulation drug effects, Glutamate-Cysteine Ligase genetics, Glutamate-Cysteine Ligase metabolism, Heme Oxygenase-1 metabolism, Lipid Peroxidation drug effects, Lung enzymology, Malondialdehyde metabolism, Mice, Mice, Inbred ICR, NF-E2-Related Factor 2 genetics, NF-E2-Related Factor 2 metabolism, Nanoparticles administration & dosage, Organ Size drug effects, Reactive Oxygen Species metabolism, Time Factors, Titanium administration & dosage, Lung drug effects, Lung pathology, Nanoparticles adverse effects, Oxidative Stress drug effects, Protective Agents metabolism, Titanium adverse effects
- Abstract
Exposure to titanium dioxide nanoparticles (TiO(2) NPs) elicits an adverse response such as oxidative damage. The molecular targets of TiO(2) NPs remain largely unidentified. In the present study, the function and signal pathway of nuclear factor erythroid 2 related factor 2 (Nrf2) in protection against TiO(2) NPs-induced oxidative stress in the mouse lung were investigated. Mice were exposed to 10 mg/kg body weight by an intratracheal administration for 15-90 days. With increasing exposed terms, TiO(2) NPs were significantly accumulated and increased the reactive oxygen species (ROS) production in lung, which resulted in severe pulmonary edema, inflammatory response and pneumonocyte apoptosis for 90 days. Furthermore, TiO(2) NPs exposure could greatly induce expression of Nrf2, heme oxygenase 1 (HO-1), and glutamate-cysteine ligase catalytic subunit (GCLC) from 15-day to 75-day exposure, whereas 90-day exposure caused significant decreases of three factors expression levels in lung. Our findings imply that the induction of Nrf2 expression is an adaptive intracellular response to TiO(2) NPs-induced oxidative stress in the mouse lung, and that Nrf2 is protective against TiO(2) NPs-induced pulmonary damages during certain exposure terms., (Copyright © 2012 Wiley Periodicals, Inc.)
- Published
- 2012
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