Objective: Detect the neurotoxic effect of titanium dioxide nanoparticles by investigation of the biochemical and histological changes in cerebral cortex of albino rats, and to evaluate the potential protective role of β-carotene against this toxicity.
Methods: Titanium dioxide nanoparticles (TiO2 NPs) administered intraperitoneal 100, 300 mg/kg, daily for 14 days besides one protected group received 10mg/kg β-carotene by gavage for 7 days prior and 14 days with 300 mg/kg nanoparticles administration, along with one control group and one group received 10mg/kg β-carotene by gavage for 21 days. Histological and histochemichal cerebral cortical tissue examination and standard biochemical methods for estimation of enzymes superoxide dismutase, glutathione peroxidase, catalase, alkaline phosphatase, gamma-glutamyl transpeptidase, and 5' nucleotidase were implemented.
Results: In contrast to administration of low dose TiO2 NPs, administration of high dose TiO2 NPs led to marked histological changes in form of decrease number of vesicular neurons and loss of background homogeneity with appearance of vacuolations and hydropic changes. Moreover, increase in astrocytes number with appearance of area of gliosis and increase in apoptosis index. Biochemical analysis showed significant decreases in the activities of the antioxidant enzymes: superoxide dismutase, glutathione peroxidase and catalase. Besides, significant decrease in the activities of alkaline phosphatase and gamma-glutamyl transpeptidase, although the activity of 5'-nucleotidase was not inclined significantly by administration of nanoparticles. These changes didn't markedly appear with the use of β-carotene.
Conclusion: High dose TiO2 NPs has neurotoxic effects but application of β-carotene may serve as a beneficial medication to protect against neurotoxicity induced by nanoparticles.