PUBLICATION

Size matters: Zebrafish (Danio rerio) as a model to study toxicity of nanoplastics from cells to the whole organism

Authors
Sendra, M., Pereiro, P., Yeste, M.P., Mercado, L., Figueras, A., Novoa, B.
ID
ZDB-PUB-201020-58
Date
2020
Source
Environmental pollution (Barking, Essex : 1987)   268: 115769 (Journal)
Registered Authors
Novoa, Beatriz
Keywords
Internalization, Nanoparticles, Polystyrene, Toxicity, Trafficking, Zebrafish
MeSH Terms
  • Animals
  • Larva
  • Microplastics
  • Nanoparticles*
  • Polystyrenes
  • Water Pollutants, Chemical*/toxicity
  • Zebrafish
PubMed
33070068 Full text @ Environ. Pollut.
Abstract
The contamination of the aquatic environment by plastic nanoparticles is becoming a major concern due to their potential adverse effects in aquatic biota. Therefore, in-depth knowledge of their uptake, trafficking and effects at cellular and systemic levels is essential to understand their potential impacts for aquatic species. In this work, zebrafish (Danio rerio) was used as a model and our aims were: i) to determine the distribution, uptake, trafficking, degradation and genotoxicity of polystyrene (PS) NPs of different sizes in a zebrafish cell line; ii) to study PS NPs accumulation, migration of immune cells and genotoxicity in larvae exposed to PS NPs; and iii) to assess how PS NPs condition the survival of zebrafish larvae exposed to a pathogen and/or how they impact the resistance of an immunodeficient zebrafish. Our results revealed that the cellular distribution differed depending on the particle size: the 50 nm PS NPs were more homogeneously distributed in the cytoplasm and the 1 μM PS NPs more agglomerated. The main endocytic mechanisms for the uptake of NPs were dynamin-dependent internalization for the 50 nm NPs and phagocytosis for the 1 μm nanoparticles. In both cases, degradation in lysosomes was the main fate of the PS NPs, which generated alkalinisation and modified cathepsin genes expression. These effects at cellular level agree with the results in vivo, since lysosomal alkalization increases oxidative stress and vice versa. Nanoparticles mainly accumulated in the gut, where they triggered reactive oxygen species, decreased expression of the antioxidant gene catalase and induced migration of immune cells. Finally, although PS NPs did not induce mortality in wild-type larvae, immunodeficient and infected larvae had decreased survival upon exposure to PS NPs. This fact could be explained by the mechanical disruption and/or the oxidative damage caused by these NPs that increase their susceptibility to pathogens.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping