(379f) In Vitro Evidence of Titanium Dioxide Nanoparticle Toxicity to Brain Cells

Titanium Dioxide Nanoparticles (TiO₂-NPs) are the second most produced engineered nanomaterial in the world with a vast majority utilized for cosmetics, sunscreen, and consumer products providing ample opportunity for human exposure throughout an individual’s lifetime. Recent studies in animal models have shown that exposure to TiO₂-NPs leads to nanoparticle accumulation in several organs including penetration of the blood brain barrier to the brain. TiO₂-NPs were also observed to increase cell death, reactive oxygen species, expression of inflammation markers and cognitive impairment. However, the mechanisms underlying TiO₂-NPs toxicity in the brain has not been extensively examined. This study investigates the mechanistic effect of TiO₂-NPs on primary neurons and astrocytes, the most abundant cell type in the brain which performs vital roles in maintenance of brain health and injury repair, by observing the effect of TiO₂-NPs on cell viability, morphology, gene expression and mitochondrial function. It was observed in concentrations as low as 25 ppm that TiO2-NPs exposure resulted in a decrease of cell viability, increase of reactive oxygen species, and increase inflammatory marker expression and mitochondrial dysfunction in neurons and astrocytes. This response has potential to impair neuron and astrocyte ability to perform vital functions resulting in brain disorder and provides insight into the mechanisms of toxicity of TiO₂-NPs in the brain.