title: Developmental benzo[a]pyrene (B[a]P) exposure impacts larval behavior and impairs adult learning in zebrafish.
abstract: Polycyclic aromatic hydrocarbons (PAHs) are produced from incomplete combustion of organic materials or fossil fuels, and are present in crude oil and coal; therefore, they are ubiquitous environmental contaminants present in urban air, dust, soil, and water. It is widely recognized that PAHs pose risks to human health, especially for the developing fetus and infant where PAH exposures have been linked to in-utero mortality, cardiovascular effects, and lower intelligence. Using the zebrafish model, we evaluated the developmental toxicity of benzo[a]pyrene (B[a]P). Zebrafish embryos were exposed from 6 to 120h post fertilization (hpf) to 0.4 and 4μM B[a]P. The Viewpoint Zebrabox systems were used to evaluate larval photomotor response (LPR) activity and we identified that exposure to 4μM B[a]P resulted in a hyperactive LPR phenotype. To evaluate the role of aryl hydrocarbon receptor (AHR) in this larval phenotype, we exposed ahr2hu2334null larvae to 4μM B[a]P. Though ahr2hu2334larvae did not display hyperactive swimming, these larvae had a decrease in LPR activity, suggesting that AHR2 plays a role in B[a]P induced larval hyperactivity. To determine if developmental B[a]P exposures would produce adult behavioral deficits, a subset of exposed animals was raised to adulthood and tested in a conditioned stimulus test using shuttleboxes. Developmentally exposed B[a]P zebrafish exhibited decreased learning and memory. Together this data demonstrates that developmental B[a]P exposure adversely impacts larval behavior, and learning in adult zebrafish.
authors.affiliation: Department of Environmental and Molecular Toxicology, Sinnhuber Aquatic Research Laboratory, Environmental Health Sciences Center, Oregon State University, Corvallis, OR, USA.
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Knecht
authors.affiliation: Department of Environmental and Molecular Toxicology, Sinnhuber Aquatic Research Laboratory, Environmental Health Sciences Center, Oregon State University, Corvallis, OR, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Truong
authors.affiliation: Department of Environmental and Molecular Toxicology, Sinnhuber Aquatic Research Laboratory, Environmental Health Sciences Center, Oregon State University, Corvallis, OR, USA.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Simonich
authors.affiliation: Department of Environmental and Molecular Toxicology, Sinnhuber Aquatic Research Laboratory, Environmental Health Sciences Center, Oregon State University, Corvallis, OR, USA. Electronic address: Robert.Tanguay@oregonstate.edu.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Tanguay
mesh_terms: D000818:Animals; D001564:Benzo(a)pyrene / Q000633:toxicity*; D003213:Conditioning, Psychological / Q000187:drug effects*; D007814:Larva / Q000187:drug effects*; D000073658:Loss of Function Mutation; D009043:Motor Activity / Q000187:drug effects*; D018336:Receptors, Aryl Hydrocarbon / Q000235:genetics; D013550:Swimming; D014874:Water Pollutants, Chemical / Q000633:toxicity; D015027:Zebrafish
chemical_list: D018336:Receptors, Aryl Hydrocarbon; D014874:Water Pollutants, Chemical; D001564:Benzo(a)pyrene
keywords: Benzo[a]pyrene; Neurotoxicity; Zebrafish