Fig. 3

Titanium quantification in rat brain (a), isolated brain microvasculature endothelial cells (b) and brain parenchyma (c) of treated (grey) and control (white) animals after IV injection of 1 mg/kg TiO₂ NPs and schematic summary of the events and potential effects on the BBB.. Quantification by inductively coupled plasma mass spectrometry (ICP-MS). Each data point represents the mean ± SD of n = 6 animals. Statistical comparison was performed by two-way ANOVA, *P < 0.05; **P < 0.01; ***P < 0.001. Consequences and hypothesis of clearance mechanism of TiO₂ NPs at the BBB (d). Transient presence of TiO₂ NPs in brain microvasculature endothelial cells leads to overexpression of cytokines and chemokines (IL-1β and IP-10), which could be linked to the modification of activity or expression of P-gp and BCRP. Integrity of the barrier is not compromised