PUBLICATION

Co-exposure with titanium dioxide nanoparticles exacerbates MCLR-induced brain injury in zebrafish

Authors
Wu, Q., Yan, W., Liu, C., Hung, T.C., Li, G.
ID
ZDB-PUB-190803-16
Date
2019
Source
The Science of the total environment   693: 133540 (Journal)
Registered Authors
Keywords
Co-exposure, Microcystin-LR, Oxidative stress, Titanium dioxide nanoparticles
MeSH Terms
  • Animals
  • Antioxidants
  • Brain Injuries
  • Fresh Water
  • Glutathione
  • Lipid Peroxidation
  • Metal Nanoparticles/toxicity*
  • Microcystins/toxicity*
  • Oxidative Stress
  • Superoxide Dismutase
  • Titanium/toxicity*
  • Water Pollutants, Chemical/toxicity*
  • Zebrafish/physiology*
PubMed
31374495 Full text @ Sci. Total Environ.
Abstract
Owing to the eutrophication in freshwater and industrial emissions, the detected concentrations of MCLR and nano-TiO2 in nature water increase year by year. The purpose of this study was to evaluate the joint effect of microcystin-LR (MCLR) and titanium dioxide nanoparticles (nano-TiO2) on the zebrafish brain and to investigate the underlying mechanisms. In this study, four-month old zebrafish were exposed to 0, 0.5, 4, and 32 μg/L MCLR and MCLR-co-nano-TiO2 (100 μg/L) for 45 days. Obvious brain injury characterized by formation of glial scars and ventriculomegaly was observed in both MCLR groups and MCLR-co-nano-TiO2 groups. In addition, our results showed the existence of nano-TiO2 aggravated MCLR-induced abnormity of swimming behavior and social behavior of zebrafish. To clarify the mechanisms of nano-TiO2 aggravated MCLR-induced brain injury, we firstly examined the reactive oxygen species (ROS) generation in the zebrafish brain. The results showed that co-exposure with nano-TiO2 could further increase ROS content compared with MCLR only groups. We also detected a significant change of lipid peroxidation products (MDA, malondialdehyde) content, antioxidant enzyme (SOD, superoxide dismutase) activity, and non-enzymatic antioxidant (GSH, glutathione) content in MCLR-co-nano-TiO2 groups. Transcriptional analysis indicated the expression of genes related to the antioxidant system was significantly altered in the zebrafish brain. Collectively, the observations in this study showed that the existence of nano-TiO2 could exacerbate the damage of the zebrafish brain through the aggravation of MCLR-induced oxidative stress, ultimately leading to the abnormity of swimming behavior and social behavior.
Genes / Markers
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Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping