Glia Cells Are Selectively Sensitive to Nanosized Titanium Dioxide Mineral Forms

Area of Science:

• Nanotechnology
• Neuroscience
• Toxicology

Background:

• Nanosized titanium dioxide (TiO2) is prevalent in consumer products.
• Previous research explored TiO2's general effects, but crystal structure-specific impacts on neural cells are less understood.

Purpose of the Study:

• To investigate the crystal structure-specific toxicity of anatase and rutile TiO2 nanoparticles on primary neural cultures.
• To assess the impact on different neural cell types, including astroglia, microglia, and mixed neuron-glia cultures.

Main Methods:

• Utilized MTT and LDH assays to measure cell viability and death.
• Exposed primary murine neural cultures (astroglia, microglia, mixed) to varying concentrations of anatase and rutile TiO2 nanoparticles for 24 or 48 hours.
• Analyzed toxicity differences based on TiO2 crystal form, cell type, brain region, concentration, and treatment duration.

Main Results:

• Neither anatase nor rutile TiO2 nanoparticles affected the viability of mixed neuron-glia cultures.
• Rutile TiO2, but not anatase, induced cell death in cortical astroglia cultures at concentrations above 10 µg/mL after 24 hours.
• Hippocampus-derived glial cultures showed less sensitivity to rutile TiO2 compared to cortical astroglia.
• Rutile TiO2 nanoparticles demonstrated toxicity towards microglia cells.

Conclusions:

• The crystal structure of TiO2 nanoparticles significantly influences their toxicity towards specific neural cell types.
• Rutile TiO2 poses a targeted risk to astroglia and microglia within the central nervous system.
• Findings suggest potential risks associated with rutile-form nano-titanium products in neurological contexts.