Dataset Information

Titanium dioxide nanoparticles impair the inner blood-retinal barrier and retinal electrophysiology through rapid ADAM17 activation and claudin-5 degradation.

ABSTRACT:

Background

Depending on their distinct properties, titanium dioxide nanoparticles (TiO₂-NPs) are manufactured extensively and widely present in our daily necessities, with growing environmental release and public concerns. In sunscreen formulations, supplementation of TiO₂-NPs may reach up to 25% (w/w). Ocular contact with TiO₂-NPs may occur accidentally in certain cases, allowing undesirable risks to human vision. This study aimed to understand the barrier integrity of retinal endothelial cells in response to TiO₂-NP exposure. bEnd.3 cells and human retinal endothelial cells (HRECs) were exposed to TiO₂-NP, followed by examination of their tight junction components and functions.

Results

TiO2-NP treatment apparently induced a broken structure of the junctional plaques, conferring decreased transendothelial electrical resistance, a permeable paracellular cleft, and improved cell migration in vitro. This might involve rapid activation of metalloproteinase, a disintegrin and metalloproteinase 17 (ADAM17), and ADAM17-mediated claudin-5 degradation. For the in vivo study, C57BL/6 mice were administered a single dose of TiO2-NP intravitreally and then subjected to a complete ophthalmology examination. Fluorescein leakage and reduced blood flow at the optical disc indicated a damaged inner blood-retinal barrier induced by TiO₂-NPs. Inappreciable change in the thickness of retinal sublayers and alleviated electroretinography amplitude were observed in the TiO₂-NP-treated eyes.

Conclusions

Overall, our data demonstrate that TiO2-NP can damage endothelial cell function, thereby affecting retinal electrophysiology.

SUBMITTER: Chan YJ

PROVIDER: S-EPMC7796566 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Publications

Titanium dioxide nanoparticles impair the inner blood-retinal barrier and retinal electrophysiology through rapid ADAM17 activation and claudin-5 degradation.

Chan Yen-Ju YJ Liao Po-Lin PL Tsai Chi-Hao CH Cheng Yu-Wen YW Lin Fan-Li FL Ho Jau-Der JD Chen Ching-Yi CY Li Ching-Hao CH

Particle and fibre toxicology 20210109 1

<h4>Background</h4>Depending on their distinct properties, titanium dioxide nanoparticles (TiO<sub>2</sub>-NPs) are manufactured extensively and widely present in our daily necessities, with growing environmental release and public concerns. In sunscreen formulations, supplementation of TiO<sub>2</sub>-NPs may reach up to 25% (w/w). Ocular contact with TiO<sub>2</sub>-NPs may occur accidentally in certain cases, allowing undesirable risks to human vision. This study aimed to understand the barri ...[more]

PMID: 33422125

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Dataset Information

Titanium dioxide nanoparticles impair the inner blood-retinal barrier and retinal electrophysiology through rapid ADAM17 activation and claudin-5 degradation.

Background

Results

Conclusions

Publications

Titanium dioxide nanoparticles impair the inner blood-retinal barrier and retinal electrophysiology through rapid ADAM17 activation and claudin-5 degradation.

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