PUBLICATION

Embryonic cardiotoxicity of weak aryl hydrocarbon receptor agonists and cyp1a inhibitor fluoranthene in the Atlantic Killifish (Fundulus heteroclitus)

Authors
Brown, D.R., Clark, B.W., Garner, L.V., Di Giulio, R.T.
ID
ZDB-PUB-160524-4
Date
2016
Source
Comparative biochemistry and physiology. Toxicology & pharmacology : CBP   188: 45-51 (Journal)
Registered Authors
Di Giulio, Richard T.
Keywords
Aryl hydrocarbon receptor agonists, Cardiotoxicity, Cytochrome P450, Development, Fundulus heteroclitus, Morpholino
MeSH Terms
  • Animals
  • Cardiotoxicity
  • Cytochrome P-450 Enzyme Inhibitors/toxicity*
  • Cytochrome P450 Family 1/antagonists & inhibitors*
  • Cytochrome P450 Family 1/metabolism
  • Dose-Response Relationship, Drug
  • Embryo, Nonmammalian/drug effects
  • Embryo, Nonmammalian/enzymology
  • Fish Proteins/agonists*
  • Fish Proteins/antagonists & inhibitors*
  • Fish Proteins/metabolism
  • Fluorenes/toxicity*
  • Fundulidae/embryology
  • Fundulidae/genetics
  • Fundulidae/metabolism*
  • Gene Expression Regulation
  • Gene Knockdown Techniques
  • Heart/drug effects*
  • Ligands
  • Myocardium/enzymology*
  • Polycyclic Aromatic Hydrocarbons/toxicity*
  • Receptors, Aryl Hydrocarbon/agonists*
  • Receptors, Aryl Hydrocarbon/genetics
  • Receptors, Aryl Hydrocarbon/metabolism
  • Risk Assessment
  • Water Pollutants, Chemical/toxicity*
PubMed
27211013 Full text @ Comp. Biochem. Physiol. C Toxicol. Pharmacol.
Abstract
High affinity aryl hydrocarbon receptor (AHR) ligands, such as certain polychlorinated biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), cause severe cardiac teratogenesis in fish embryos. Moderately strong AHR agonists, for example benzo[a]pyrene and β-naphthoflavone, are capable of causing similar cardiotoxic effects, particularly when coupled with cytochrome P450 1A (CYP1A) inhibitors (e.g., fluoranthene (FL). Additionally, some weaker AHR agonists (carbaryl, 2-methylindole, 3-methylindole, and phenanthrene) are known to also cause cardiotoxicity in zebrafish (Danio rerio) embryos when coupled with FL; however, the cardiotoxic effects were not mediated specifically by AHR stimulation. This study was performed to determine if binary exposure to weak AHR agonists and FL were also capable of causing cardiotoxicity in Atlantic killifish Fundulus heteroclitus embryos. Binary exposures were performed in both naïve and PAH-adapted killifish embryos to examine resistance to weak agonists and FL binary exposures. Weak agonists used in this study included the following: carbaryl, phenanthrene, 2-methylindole, 3-methylindole, indigo, and indirubin. Carbaryl, indigo, and indirubin induced the highest CYP1 activity levels in naïve killifish embryos, but no significant CYP1 induction was observed in the PAH-adapted killifish. Embryos were coexposed to subteratogenic levels of each agonist and 500 μg/L FL to assess if binary administration could cause cardiotoxicity. Indigo and indirubin coupled with FL caused cardiac teratogenesis in naïve killifish, but coexposures did not produce cardiac chamber abnormalities in the PAH-adapted population. Knockdown of AHR2 in naïve killifish embryos did not prevent cardiac teratogenesis. The data suggest a unique mechanism of cardiotoxicity that is not driven by AHR2 activation.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping