Background
Nanoparticulate titanium dioxide (Nano-TiO2) has been widely used in food industry, and it has been demonstrated to have adverse effects on mice and human stomach, but its mechanism is rarely concerned. The
Conclusions
The gastric toxicity of mice induced by chronic exposure to low dose nano-TiO2 may be associated with oxidative stress and mitochondria-mediated apoptosis in mice.
Methods
Mice were continuously exposed to nano-TiO2 with 1.25, 2.5 and 5 mg/kg bw by intragastric administration for 9 months in the present study. The ultrastructure, levels of reactive oxygen species (ROS) and peroxides, activities of antioxidant enzymes and mitochondria-related enzymes, ATP contents as well as apoptosis-related factors expression in mice stomach were examined.
Results
Oxidative stress, apoptosis and nano-TiO2 aggregation were found in gastric mucosal smooth muscle cells after nano-TiO2 exposure. Nano-TiO2 exposure also resulted in the over-production of ROS and peroxides, decrease of ATP production and activities of antioxidant enzymes and mitochondria-related ATPases, upregulation of apoptosis-related factors including γH2AX, Cyt c, caspase 3, and p-JNK expression, and down-regulation of Bcl-2 expression in mice stomach. Conclusions: The gastric toxicity of mice induced by chronic exposure to low dose nano-TiO2 may be associated with oxidative stress and mitochondria-mediated apoptosis in mice.