Introduction: Titanium dioxide nanoparticles (Tio2 NPs) represents the most abundant and widely consumed nanoparticles, owing to their unique characteristics. Their extensive use raised considerable concerns about their possible toxicity.
Aim of Work: Investigating the neurotoxic impact of oral administration of different doses of Tio2 NPs on adult rats' cerebellar cortex. Other than, the potential protective capability of β-carotene was evaluated.
Material and Methods: Fifty male albino adult rats were allocated into: group I, group ΙΙ (Tio2 NPs for 60 days), group ΙII (β-carotene with dosage of 15 mg/kg, for 10 days before starting Tio2 NPs intake followed by both ꞵ-carotene and Tio2 NPs, for 60 days). Groups II and III were subdivided according to administrated doses of Tio2 NPs into: IIa & IIIa (50 mg/kg) and IIb & IIIb (200 mg/kg). Body & cerebellum weights were recorded. Blood samples were taken for biochemical analysis of malondialdehyde (MDA), Glutathione peroxidase (GPx), interleukin-6 (IL-6) and acetyl choline esterase (ACE). Cerebellum specimens were processed for H&E, immunohistochemical staining (for GFAP, caspase-3 and iNOS) and toluidine blue-stained semithin sections. Mean thickness of granular cell layer, number of astrocytes, area percent of GFAP, caspase-3 and iNOS immunoreactivity were measured and statistically analyzed.
Results: Biochemical and histological alterations after Tio2 NPs intake were reported in group II. As regard to control, rats' body & cerebellum weights, GPx and ACE significantly decreased alongside significant increase in MDA and IL-6. Granular cell layer thickness was significantly decreased. Whereas astrocytes number, area percent of GFAP, caspase-3 and iNOS positive immunoreactivity were significantly increased. Changes were more intense in subgroup IIb than IIa. Group III revealed ameliorated histological and biochemical alterations with increase in rats' body and cerebellum weights.
Conclusion: ꞵ-carotene possesses protective effects against Tio2 NPs neurotoxic hazards on cerebellar cortex.