Ecotoxicology

, Volume 22, Issue 2, pp 387–401

Differential sensitivity to pro-oxidant exposure in two populations of killifish (Fundulus heteroclitus)

Article

DOI: 10.1007/s10646-012-1033-x

Cite this article as:
Harbeitner, R.C., Hahn, M.E. & Timme-Laragy, A.R. Ecotoxicology (2013) 22: 387. doi:10.1007/s10646-012-1033-x

Abstract

New Bedford Harbor (MA, U.S.A.; NBH) is a Superfund site inhabited by Atlantic killifish (Fundulus heteroclitus) with altered aryl hydrocarbon receptor (Ahr) signaling, leading to resistance to effects of polychlorinated biphenyls (PCBs) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The Ahr is a transcription factor that regulates gene expression of many Phase I and II detoxifying enzymes and interacts with Nrf2, a transcription factor that regulates the response to oxidative stress. This study tested the hypothesis that PCB-resistant killifish exhibit altered sensitivity to oxidative stress. Killifish F1 embryos from NBH and a clean reference site (Scorton Creek, MA, U.S.A.; SC) were exposed to model pro-oxidant and Nrf2-activator, tert-butylhydroquinone (tBHQ). Embryos were exposed at specific embryonic developmental stages (5, 7, and 9 days post fertilization) and toxicity was assessed, using a deformity score, survival, heart rate, and gene expression to compare sensitivity between PCB -resistant and -sensitive (reference) populations. Acute exposure to tBHQ resulted in transient reduction in heart rate in NBH and SC F1 embryos. However, embryos from NBH were more sensitive to tBHQ, with more frequent and severe deformities, including pericardial edema, tail deformities, small body size, and reduced pigment and erythrocytes. NBH embryos had lower basal expression of antioxidant genes catalase and glutathione-S-transferase alpha (gsta), and upon exposure to tBHQ, exhibited lower levels of expression of catalase, gsta, and superoxide dismutase compared to controls. This result suggests that adaptation to tolerate PCBs has altered the sensitivity of NBH fish to oxidative stress during embryonic development, demonstrating a cost of the PCB resistance adaptation.

Keywords

Fundulus heteroclitusNew Bedford HarborOxidative StressDeformitiesEcotoxicologyAdaptation

Abbreviations

Ahr

Aryl hydrocarbon receptor

PCBs

Polychlorinated biphenyls

TCDD

2,3,7,8-Tetrachlorodibenzo-p-dioxin

NBH

New Bedford Harbor

SC

Scorton creek

tBHQ

tert-butylhydroquinone

HAHs

Halogenated aromatic hydrocarbons

PAHs

Polycyclic aromatic hydrocarbons

PCB-126

3,3′,4,4′,5-pentachlorobiphenyl

Arnt

Aryl hydrocarbon receptor nuclear translocator

XRE

Xenobiotic response element

Cyp1a

Cytochrome P4501a

Nrf2

Nuclear factor erythroid-related factor-2

ROS

Reactive oxygen species

Keap1

Kelch-like ECH-associated protein 1

ARE

Antioxidant response element

tBOOH

tert-butylhydroperoxide

IVF

In vitro fertilization

ER

Elizabeth River

Supplementary material

10646_2012_1033_MOESM1_ESM.docx (16 kb)
Supplementary material 1 (DOCX 15 kb)
10646_2012_1033_MOESM2_ESM.docx (37 kb)
Supplementary material 2 (DOCX 37 kb)

Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Biology DepartmentWoods Hole Oceanographic InstitutionWoods HoleUSA
  2. 2.Division of Environmental Health, Department of Public HealthSchool of Public Health and Health Sciences, University of Massachusetts AmherstAmherstUSA