1
|
Li Y, Liu S, Cheng H, Chen X, Shen X, Cai Y. Dynamic transcriptome response in Meretrix meretrix to Aroclor 1254 exposure. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 207:111485. [PMID: 33254386 DOI: 10.1016/j.ecoenv.2020.111485] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/08/2020] [Accepted: 10/09/2020] [Indexed: 06/12/2023]
Abstract
Polychlorinated biphenyls (PCBs) are well-known persistent organic pollutants; they have toxic effects on the immune system, reproductive system, and endocrine system by changing the metabolism of the body. To elucidate the underlying molecular mechanism, the clam Meretrix meretrix was exposed to 10 and 1000 ng/L Aroclor 1254 and natural seawater (control). Samples from clams exposed to natural seawater and those exposed to Aroclor 1254 for 1 and 3 days were individually collected for transcriptome analysis. After assembly, more than 535,157 transcripts with a mean length of 949 bp and an N50 length of 1279 bp were obtained; a final set of 177,142 unigenes was generated. In the present study, 5101 differentially expressed genes were identified. The differentially expressed genes were related to detoxification metabolism, oxidative stress, immune response, and endocrine system disruption. Of these genes, under the Aroclor 1254 exposure, cytochrome P450 20A1 (2.06-4.46 folds), glutathione S-transferase (2.25-3.80 folds), multidrug resistance-associated protein 1-like (1.49-2.92 folds), peroxidase-like protein (1.33-4.26 folds), lysozyme (1.61-2.05 folds), bcl-2 like 1 protein (1.14-2.29 folds) and vitellogenin (1.09-1.19 folds) showed been significantly induced expressed. At the same time, some genes were down regulated, including cytochrome P450 2J5 (-1.20 ~ -2.86 folds), cytochrome P450 3A24 (-1.40 ~ -4.08 folds), C1q (-1.27 ~ -1.66 folds), Sulfotransferase (-1.51 ~ -1.84 folds), monocarboxylate transporter 10 (-1.30 ~ -4.70 folds), 3-beta hydroxysteroid dehydrogenase (-1.43 ~ -2.81 folds) and beta-galactosidase (-1.23 ~ -2.23 folds). Furthermore, it showed that the expression levels of CYP2J5, glutathione S-transferase, 3-beta hydroxysteroid dehydrogenase and beta-galactosidase had time responses and dose responses. The present study provided insights into the toxic effects of Aroclor 1254 exposure in M. meretrix.
Collapse
Affiliation(s)
- Yongqi Li
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Shishi Liu
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Hanliang Cheng
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Xiangning Chen
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Xin Shen
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China.
| | - Yuefeng Cai
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China.
| |
Collapse
|
2
|
Silvestre F. Signaling pathways of oxidative stress in aquatic organisms exposed to xenobiotics. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2020; 333:436-448. [DOI: 10.1002/jez.2356] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/03/2020] [Accepted: 03/04/2020] [Indexed: 12/18/2022]
Affiliation(s)
- Frédéric Silvestre
- Institute of Life, Earth, and Environment (ILEE)University of Namur Bruxelles Namur Belgium
| |
Collapse
|
3
|
Crawford KA, Clark BW, Heiger-Bernays WJ, Karchner SI, Hahn ME, Nacci DE, Schlezinger JJ. Tributyltin disrupts fin development in Fundulus heteroclitus from both PCB-sensitive and resistant populations: Investigations of potential interactions between AHR and PPARγ. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2020; 218:105334. [PMID: 31743820 PMCID: PMC6935467 DOI: 10.1016/j.aquatox.2019.105334] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 10/07/2019] [Accepted: 10/12/2019] [Indexed: 05/09/2023]
Abstract
Tributyltin (TBT) and dioxin-like polychlorinated biphenyls (PCBs) are environmental contaminants that are highly toxic to fish and co-occur in New Bedford Harbor (NBH), an estuarine Superfund site located in Massachusetts, USA. Atlantic killifish (Fundulus heteroclitus) that reside in NBH (and other highly contaminated sites along the east coast of the United States) have developed resistance to activation of the aryl hydrocarbon receptor (AHR) pathway and the toxicity of dioxin-like chemicals, such as 3,3',4,4',5-pentachlorobiphenyl, PCB126. In many biological systems, TBT disregulates adipose and bone development via the PPARγ-RXR pathway; AHR activation also disrupts adipose and bone homeostasis, potentially through molecular crosstalk between AHR and PPARγ. However, little is known about how co-exposure and the interaction of these pathways modulate the toxicological effects of these contaminants. Here, we tested the hypotheses that TBT would induce teratogenesis in killifish via activation of PPARγ and that PCB126 co-exposure would suppress PPARγ pathway activation in PCB-sensitive killifish from a reference site (Scorton Creek, SC, PCB-sensitive) but not in PCB-tolerant NBH killifish. Killifish embryos from both populations exposed to TBT (50 and 100 nM) displayed caudal fin deformities. TBT did not change the expression of pparg or its target genes related to adipogenesis (fabp11a and fabp1b) in either population. However, expression of osx/sp7, an osteoblast marker gene, and col2a1b, a chondroblast marker gene, was significantly suppressed by TBT only in SC killifish. An RXR-specific agonist, but not a PPARγ-specific agonist, induced caudal fin deformities like those observed in TBT-treated embryos. PCB126 did not induce caudal fin deformities and did not exacerbate TBT-induced fin deformities. Further, PCB126 increased expression of pparg in SC embryos and not NBH embryos, but did not change the expression of fabp1b. Taken together, these results suggest that in killifish embryos the PPARγ pathway is regulated in part by AHR, but is minimally active at least in this early life stage. In killifish, RXR activation, rather than PPARγ activation, appears to be the mechanism by which TBT induces caudal fin teratogenicity, which is not modulated by AHR responsiveness.
Collapse
Affiliation(s)
- K A Crawford
- Department of Environmental Health, Boston University School of Public Health, Boston, MA, USA; Boston University Superfund Research Program, Boston, MA, USA; Oak Ridge Institute for Science and Education at Atlantic Ecology Division, Office of Research and Development, US Environmental Protection Agency, Narragansett, RI, USA
| | - B W Clark
- Boston University Superfund Research Program, Boston, MA, USA; Oak Ridge Institute for Science and Education at Atlantic Ecology Division, Office of Research and Development, US Environmental Protection Agency, Narragansett, RI, USA
| | - W J Heiger-Bernays
- Department of Environmental Health, Boston University School of Public Health, Boston, MA, USA; Boston University Superfund Research Program, Boston, MA, USA; Oak Ridge Institute for Science and Education at Atlantic Ecology Division, Office of Research and Development, US Environmental Protection Agency, Narragansett, RI, USA
| | - S I Karchner
- Boston University Superfund Research Program, Boston, MA, USA; Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA; Oak Ridge Institute for Science and Education at Atlantic Ecology Division, Office of Research and Development, US Environmental Protection Agency, Narragansett, RI, USA
| | - M E Hahn
- Boston University Superfund Research Program, Boston, MA, USA; Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA; Oak Ridge Institute for Science and Education at Atlantic Ecology Division, Office of Research and Development, US Environmental Protection Agency, Narragansett, RI, USA
| | - D E Nacci
- Atlantic Ecology Division, Office of Research and Development, US Environmental Protection Agency, Narragansett, RI, USA; Oak Ridge Institute for Science and Education at Atlantic Ecology Division, Office of Research and Development, US Environmental Protection Agency, Narragansett, RI, USA
| | - J J Schlezinger
- Department of Environmental Health, Boston University School of Public Health, Boston, MA, USA; Boston University Superfund Research Program, Boston, MA, USA; Oak Ridge Institute for Science and Education at Atlantic Ecology Division, Office of Research and Development, US Environmental Protection Agency, Narragansett, RI, USA.
| |
Collapse
|
4
|
Crawford KA, Clark BW, Heiger-Bernays WJ, Karchner SI, Claus Henn BG, Griffith KN, Howes BL, Schlezinger DR, Hahn ME, Nacci DE, Schlezinger JJ. Altered lipid homeostasis in a PCB-resistant Atlantic killifish (Fundulus heteroclitus) population from New Bedford Harbor, MA, U.S.A. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2019; 210:30-43. [PMID: 30822701 PMCID: PMC6544361 DOI: 10.1016/j.aquatox.2019.02.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/13/2019] [Accepted: 02/16/2019] [Indexed: 05/09/2023]
Abstract
Sentinel species such as the Atlantic killifish (Fundulus heteroclitus) living in urban waterways can be used as toxicological models to understand impacts of environmental metabolism disrupting compound (MDC) exposure on both wildlife and humans. Exposure to MDCs is associated with increased risk of metabolic syndrome, including impaired lipid and glucose homeostasis, adipogenesis, appetite control, and basal metabolism. MDCs are ubiquitous in the environment, including in aquatic environments. New Bedford Harbor (NBH), Massachusetts is polluted with polychlorinated biphenyls (PCBs), and, as we show for the first time, tin (Sn). PCBs and organotins are ligands for two receptor systems known to regulate lipid homeostasis, the aryl hydrocarbon receptor (AHR) and the peroxisome proliferator-activated receptors (PPARs), respectively. In the current study, we compared lipid homeostasis in laboratory-reared killifish from NBH (F2) and a reference location (Scorton Creek, Massachusetts; F1 and F2) to evaluate how adaptation to local conditions may influence responses to MDCs. Adult killifish from each population were exposed to 3,3',4,4',5-pentachlorobiphenyl (PCB126, dioxin-like), 2,2',4,4',5,5'-hexachlorobiphenyl (PCB153, non-dioxin-like), or tributyltin (TBT, a PPARγ ligand) by a single intraperitoneal injection and analyzed after 3 days. AHR activation was assessed by measuring cyp1a mRNA expression. Lipid homeostasis was evaluated phenotypically by measuring liver triglycerides and organosomatic indices, and at the molecular level by measuring the mRNA expression of pparg and ppara and a target gene for each receptor. Acute MDC exposure did not affect phenotypic outcomes. However, overall NBH killifish had higher liver triglycerides and adiposomatic indices than SC killifish. Both season and population were significant predictors of the lipid phenotype. Acute MDC exposure altered hepatic gene expression only in male killifish from SC. PCB126 exposure induced cyp1a and pparg, whereas PCB153 exposure induced ppara. TBT exposure did not induce ppar-dependent pathways. Comparison of lipid homeostasis in two killifish populations extends our understanding of how MDCs act on fish and provides a basis to infer adaptive benefits of these differences in the wild.
Collapse
Affiliation(s)
- Kathryn A Crawford
- Department of Environmental Health, Boston University School of Public Health, Boston, MA, USA; Boston University Superfund Research Program, Boston, MA, USA.
| | - Bryan W Clark
- Oak Ridge Institute for Science and Education at the Office of Research and Development, US Environmental Protection Agency, Narragansett, RI, USA
| | - Wendy J Heiger-Bernays
- Department of Environmental Health, Boston University School of Public Health, Boston, MA, USA; Boston University Superfund Research Program, Boston, MA, USA
| | - Sibel I Karchner
- Boston University Superfund Research Program, Boston, MA, USA; Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Birgit G Claus Henn
- Department of Environmental Health, Boston University School of Public Health, Boston, MA, USA
| | - Kevin N Griffith
- Department of Health Law, Policy and Management, Boston University School of Public Health, Boston, MA, USA
| | - Brian L Howes
- School for Marine Science and Technology, University of Massachusetts, Dartmouth, New Bedford, MA, USA
| | - David R Schlezinger
- School for Marine Science and Technology, University of Massachusetts, Dartmouth, New Bedford, MA, USA
| | - Mark E Hahn
- Department of Environmental Health, Boston University School of Public Health, Boston, MA, USA; Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Diane E Nacci
- Atlantic Ecology Division, Office of Research and Development, US Environmental Protection Agency, Narragansett, RI, USA
| | - Jennifer J Schlezinger
- Department of Environmental Health, Boston University School of Public Health, Boston, MA, USA; Boston University Superfund Research Program, Boston, MA, USA
| |
Collapse
|
5
|
Brown SE, Sant KE, Fleischman SM, Venezia O, Roy MA, Zhao L, Timme-Laragy AR. Pancreatic beta cells are a sensitive target of embryonic exposure to butylparaben in zebrafish (Danio rerio). Birth Defects Res 2018. [PMID: 29516647 DOI: 10.1002/bdr2.1215] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Butylparaben (butyl p-hydroxybenzoic acid) is a common cosmetic and pharmaceutical preservative reported to induce oxidative stress and endocrine disruption. Embryonic development is sensitive to oxidative stress, with redox potentials playing critical roles in progenitor cell fate decisions. Because pancreatic beta cells have been reported to have low antioxidant gene expression, they may be sensitive targets of oxidative stress. We tested the hypotheses that butylparaben causes oxidative stress in the developing embryo, and that pancreatic beta cells are a sensitive target of butylparaben embryotoxicity. METHODS Transgenic insulin:GFP zebrafish embryos (Danio rerio) were treated daily with 0, 250, 500, 1,000, and 3,000 nM butylparaben. Pancreatic islet and whole embryo development were examined though 7 days postfertilization, and gene expression was measured by quantitative real-time PCR. Glutathione (GSH) and cysteine redox content were measured at 28 hr postfertilization using HPLC. RESULTS Butylparaben exposure caused intestinal effusion, pericardial edema, and accelerated yolk utilization. At 250 nM, beta cell area increased by as much as 55%, and increased incidence of two aberrant morphologies were observed-fragmentation of the islet cluster and ectopic beta cells. Butylparaben concentrations of 500 and 1,000 nM increased GSH by 10 and 40%, respectively. Butylparaben exposure downregulated transcription factor pdx1, as well as genes involved in GSH synthesis, while upregulating GSH-disulfide reductase (gsr). CONCLUSIONS The endocrine pancreas is a sensitive target of embryonic exposure to butylparaben, which also causes developmental deformities and perturbs redox conditions in the embryo.
Collapse
Affiliation(s)
- Sarah E Brown
- Department of Environmental Health Sciences, University of Massachusetts Amherst, 686 N. Pleasant St, Amherst, Massachusetts 01003-9303
| | - Karilyn E Sant
- Department of Environmental Health Sciences, University of Massachusetts Amherst, 686 N. Pleasant St, Amherst, Massachusetts 01003-9303
| | - Shana M Fleischman
- Department of Environmental Health Sciences, University of Massachusetts Amherst, 686 N. Pleasant St, Amherst, Massachusetts 01003-9303
| | - Olivia Venezia
- Department of Environmental Health Sciences, University of Massachusetts Amherst, 686 N. Pleasant St, Amherst, Massachusetts 01003-9303
| | - Monika A Roy
- Department of Environmental Health Sciences, University of Massachusetts Amherst, 686 N. Pleasant St, Amherst, Massachusetts 01003-9303.,Biotechnology Training Program, University of Massachusetts Amherst, Massachusetts 01003
| | - Ling Zhao
- Department of Nutrition, University of Tennessee Knoxville, 1215 W. Cumberland Ave., 229 Jessie Harris Building, Knoxville, Tennessee 37996-1920
| | - Alicia R Timme-Laragy
- Department of Environmental Health Sciences, University of Massachusetts Amherst, 686 N. Pleasant St, Amherst, Massachusetts 01003-9303
| |
Collapse
|
6
|
Brady SP, Monosson E, Matson CW, Bickham JW. Evolutionary toxicology: Toward a unified understanding of life's response to toxic chemicals. Evol Appl 2017; 10:745-751. [PMID: 29151867 PMCID: PMC5680415 DOI: 10.1111/eva.12519] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Affiliation(s)
- Steven P Brady
- Biology Department Southern Connecticut State University New Haven CT USA
| | - Emily Monosson
- The Ronin Institute for Independent Scholars and Department of Environmental Conservation University of Massachusetts Amherst MA USA
| | - Cole W Matson
- Department of Environmental Science and Center for Reservoir and Aquatic Systems Research (CRASR) Baylor University Waco TX USA
| | - John W Bickham
- Department of Wildlife & Fisheries Sciences Texas A&M University College Station College Station TX USA
| |
Collapse
|
7
|
Whitehead A, Clark BW, Reid NM, Hahn ME, Nacci D. When evolution is the solution to pollution: Key principles, and lessons from rapid repeated adaptation of killifish ( Fundulus heteroclitus) populations. Evol Appl 2017; 10:762-783. [PMID: 29151869 PMCID: PMC5680427 DOI: 10.1111/eva.12470] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 02/10/2017] [Indexed: 12/18/2022] Open
Abstract
For most species, evolutionary adaptation is not expected to be sufficiently rapid to buffer the effects of human‐mediated environmental changes, including environmental pollution. Here we review how key features of populations, the characteristics of environmental pollution, and the genetic architecture underlying adaptive traits, may interact to shape the likelihood of evolutionary rescue from pollution. Large populations of Atlantic killifish (Fundulus heteroclitus) persist in some of the most contaminated estuaries of the United States, and killifish studies have provided some of the first insights into the types of genomic changes that enable rapid evolutionary rescue from complexly degraded environments. We describe how selection by industrial pollutants and other stressors has acted on multiple populations of killifish and posit that extreme nucleotide diversity uniquely positions this species for successful evolutionary adaptation. Mechanistic studies have identified some of the genetic underpinnings of adaptation to a well‐studied class of toxic pollutants; however, multiple genetic regions under selection in wild populations seem to reflect more complex responses to diverse native stressors and/or compensatory responses to primary adaptation. The discovery of these pollution‐adapted killifish populations suggests that the evolutionary influence of anthropogenic stressors as selective agents occurs widely. Yet adaptation to chemical pollution in terrestrial and aquatic vertebrate wildlife may rarely be a successful “solution to pollution” because potentially adaptive phenotypes may be complex and incur fitness costs, and therefore be unlikely to evolve quickly enough, especially in species with small population sizes.
Collapse
Affiliation(s)
- Andrew Whitehead
- Department of Environmental Toxicology University of California Davis Davis CA USA
| | - Bryan W Clark
- Atlantic Ecology Division National Health and Environmental Effects Research Laboratory Office of Research and Development Oak Ridge Institute for Science and Education US Environmental Protection Agency Narragansett RI USA
| | - Noah M Reid
- Department of Molecular and Cell Biology University of Connecticut Storrs CT USA
| | - Mark E Hahn
- Department of Biology Woods Hole Oceanographic Institution Woods Hole MA USA.,Superfund Research Program Boston University Boston MA USA
| | - Diane Nacci
- Atlantic Ecology Division National Health and Environmental Effects Research Laboratory Office of Research and Development US Environmental Protection Agency Narragansett RI USA
| |
Collapse
|
8
|
Oziolor EM, Bickham JW, Matson CW. Evolutionary toxicology in an omics world. Evol Appl 2017; 10:752-761. [PMID: 29151868 PMCID: PMC5680431 DOI: 10.1111/eva.12462] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Accepted: 01/13/2017] [Indexed: 12/11/2022] Open
Abstract
Evolutionary toxicology is a young field that has grown rapidly in the past two decades. The potential of this field comes from the ability to link chemical contamination to multigenerational and population-wide effects in various species. The advancements and rapidly decreasing costs of -omic tools are improving the power and resolution of evolutionary toxicology studies. In this manuscript, we aim to address the trajectories and perspectives for conducting evolutionary toxicology studies with -omic approaches. We discuss the complementarity of using multiple -omic tools (genomics, eDNA, transcriptomics, proteomics, and metabolomics) for utility in understanding the toxicological relevance of adaptive responses in populations. In addition, we discuss phenotypic plasticity and its relevance to transcriptomic studies in toxicology. As evolutionary toxicology grows and expands its capacity to link toxicology with population-wide end points, we emphasize the applications of such studies in answering questions about ecological and population health, as well as future applicability to regulation. Thus, we aim to emphasize the enormous potential for evolutionary toxicology in an -omics world and give perspectives on the directions of future investigations.
Collapse
Affiliation(s)
- Elias M Oziolor
- Department of Environmental Science Center for Reservoir and Aquatic Systems Research (CRASR), and the Institute for Biomedical Studies Baylor University Waco TX USA
| | - John W Bickham
- Department of Wildlife and Fisheries Science Texas A&M University College Station TX USA
| | - Cole W Matson
- Department of Environmental Science Center for Reservoir and Aquatic Systems Research (CRASR), and the Institute for Biomedical Studies Baylor University Waco TX USA
| |
Collapse
|
9
|
M Oziolor E, De Schamphelaere K, Matson CW. Evolutionary toxicology: Meta-analysis of evolutionary events in response to chemical stressors. ECOTOXICOLOGY (LONDON, ENGLAND) 2016; 25:1858-1866. [PMID: 27699564 DOI: 10.1007/s10646-016-1735-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/24/2016] [Indexed: 06/06/2023]
Abstract
The regulatory decision-making process regarding chemical safety is most often informed by evidence based on ecotoxicity tests that consider growth, reproduction and survival as end-points, which can be quantitatively linked to short-term population outcomes. Changes in these end-points resulting from chemical exposure can cause alterations in micro-evolutionary forces (mutation, drift, selection and gene flow) that control the genetic composition of populations. With multi-generation exposures, anthropogenic contamination can lead to a population with an altered genetic composition, which may respond differently to future stressors. These evolutionary changes are rarely discussed in regulatory or risk assessment frameworks, but the growing body of literature that documents their existence suggests that these important population-level impacts should be considered. In this meta-analysis we have compared existing contamination levels of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) that have been documented to be associated with evolutionary changes in resident aquatic organisms to regulatory benchmarks for these contaminants. The original intent of this project was to perform a meta-analysis on evolutionary events associated with PCB and PAH contamination. However, this effort was hindered by a lack of consistency in congener selection for "total" PCB or PAH measurements. We expanded this manuscript to include a discussion of methods used to determine PCB and PAH total contamination in addition to comparing regulatory guidelines and contamination that has caused evolutionary effects. Micro-evolutionary responses often lead populations onto unique and unpredictable trajectories. Therefore, to better understand the risk of population-wide alterations occurring, we need to improve comparisons of chemical contamination between affected locations. In this manuscript we offer several possibilities to unify chemical comparisons for PCBs and PAHs that would improve comparability among evolutionary toxicology investigations, and with regulatory guidelines. In addition, we identify studies documenting evolutionary change in the presence of PCB and PAH contamination levels below applicable regulatory benchmarks.
Collapse
Affiliation(s)
- Elias M Oziolor
- Department of Environmental Science, Center for Reservoir and Aquatic Systems Research (CRASR), Institute for Biomedical Studies, Baylor University, Waco, TX, 76798, USA
| | - Karel De Schamphelaere
- Laboratory of Environmental Toxicology and Aquatic Ecology, GhEnToxLab unit, Ghent University, Jozef Plateaustraat 22, Gent, B-9000, Belgium
| | - Cole W Matson
- Department of Environmental Science, Center for Reservoir and Aquatic Systems Research (CRASR), Institute for Biomedical Studies, Baylor University, Waco, TX, 76798, USA.
| |
Collapse
|
10
|
Oziolor EM, Dubansky B, Burggren WW, Matson CW. Cross-resistance in Gulf killifish (Fundulus grandis) populations resistant to dioxin-like compounds. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2016; 175:222-231. [PMID: 27064400 DOI: 10.1016/j.aquatox.2016.03.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 03/18/2016] [Accepted: 03/21/2016] [Indexed: 06/05/2023]
Abstract
The Houston Ship Channel (HSC) in Houston, Texas is an aquatic environment with a long history of contamination, including polychlorinated dibenzodioxins (PCDD), polychlorinated dibenzofurans (PCDF), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and heavy metals. Populations of Gulf killifish (Fundulus grandis) from the HSC have adapted to resist developmental cardiac deformities caused by dioxin-like compounds (DLCs). Contaminants in the HSC have acted as a strong selective pressure on resident Gulf killifish populations. Rapid adaptation can lead to fitness costs, some as a direct result of the mechanisms involved in the adaptive process, whereas other adaptations may be more general. To explore potential fitness costs, we evaluated two Gulf killifish populations with documented resistance to DLC-induced cardiac teratogenesis (Patrick Bayou and Vince Bayou), and one previously characterized reference population (Gangs Bayou). We also characterized a previously unstudied population from Galveston Bay as an additional reference population (Smith Point). We tested the sensitivity of F1 larvae from these four populations to two classes of pesticides (pyrethroid (permethrin) and carbamate (carbaryl)) and two model pro-oxidants (tert-butyl hydroquinone (tBHQ) and tert-butyl hydroperoxide (tBOOH)). In addition, we explored their responses to hypoxia and measured resting metabolic rates (M.O2). Both adapted populations were cross-resistant to the toxicity of carbaryl and both pro-oxidants tested. There were no population differences in sensitivity to permethrin. On the other hand, one reference population (Gangs Bayou) was less sensitive to hypoxia, and maintained a lower M.O2 . However, there were no differences in hypoxia tolerance or resting metabolic rate between the second reference and the two adapted populations. This investigation emphasizes the importance of including multiple reference populations to clearly link fitness costs or cross-resistance to pollution adaptation, rather than to unrelated environmental or ecological differences. When compared to previous literature on adapted populations of Fundulus heteroclitus, we see a mixture of similarities and differences, suggesting that F. grandis adapted phenotypes likely involve multiple mechanisms, which may not be completely consistent among adapted populations.
Collapse
Affiliation(s)
- Elias M Oziolor
- Department of Environmental Science, Center for Reservoir and Aquatic Systems Research (CRASR) and the Institute for Biomedical Studies, Baylor University, Waco, TX 76798, USA
| | - Benjamin Dubansky
- Department of Biological Sciences, University of North Texas, Denton, TX 76203, USA
| | - Warren W Burggren
- Department of Biological Sciences, University of North Texas, Denton, TX 76203, USA
| | - Cole W Matson
- Department of Environmental Science, Center for Reservoir and Aquatic Systems Research (CRASR) and the Institute for Biomedical Studies, Baylor University, Waco, TX 76798, USA.
| |
Collapse
|
11
|
Félix LM, Vidal AM, Serafim C, Valentim AM, Antunes LM, Campos S, Matos M, Monteiro SM, Coimbra AM. Ketamine-induced oxidative stress at different developmental stages of zebrafish (Danio rerio) embryos. RSC Adv 2016. [DOI: 10.1039/c6ra08298j] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The changes induced by ketamine exposure were developmental stage-dependent, and related with the gradual development of the antioxidant defense system of the embryo, which is dependent on changes in energy-sensing pathways.
Collapse
Affiliation(s)
- Luís M. Félix
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
- Laboratory Animal Science (LAS)
| | - Ana M. Vidal
- Life Sciences and Environment School (ECVA)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
| | - Cindy Serafim
- Life Sciences and Environment School (ECVA)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
| | - Ana M. Valentim
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
- Laboratory Animal Science (LAS)
| | - Luís M. Antunes
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
- Laboratory Animal Science (LAS)
| | - Sónia Campos
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
- Laboratory Animal Science (LAS)
| | - Manuela Matos
- Biosystems & Integrative Sciences Institute (BioISI)
- Faculty of Sciences
- University of Lisboa
- Lisboa
- Portugal
| | - Sandra M. Monteiro
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
| | - Ana M. Coimbra
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
| |
Collapse
|
12
|
Rousseau ME, Sant KE, Borden LR, Franks DG, Hahn ME, Timme-Laragy AR. Regulation of Ahr signaling by Nrf2 during development: Effects of Nrf2a deficiency on PCB126 embryotoxicity in zebrafish (Danio rerio). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2015; 167:157-71. [PMID: 26325326 PMCID: PMC4703126 DOI: 10.1016/j.aquatox.2015.08.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 08/05/2015] [Accepted: 08/07/2015] [Indexed: 05/23/2023]
Abstract
The embryotoxicity of co-planar PCBs is regulated by the aryl hydrocarbon receptor (Ahr), and has been reported to involve oxidative stress. Ahr participates in crosstalk with another transcription factor, Nfe2l2, or Nrf2. Nrf2 binds to antioxidant response elements to regulate the adaptive response to oxidative stress. To explore aspects of the crosstalk between Nrf2 and Ahr and its impact on development, we used zebrafish (Danio rerio) with a mutated DNA binding domain in Nrf2a (nrf2a(fh318/fh318)), rendering these embryos more sensitive to oxidative stress. Embryos were exposed to 2 nM or 5 nM PCB126 at 24 h post fertilization (prim-5 stage of pharyngula) and examined for gene expression and morphology at 4 days post fertilization (dpf; protruding - mouth stage). Nrf2a mutant eleutheroembryos were more sensitive to PCB126 toxicity at 4 dpf, and in the absence of treatment also displayed some subtle developmental differences from wildtype embryos, including delayed inflation of the swim bladder and smaller yolk sacs. We used qPCR to measure changes in expression of the nrf gene family, keap1a, keap1b, the ahr gene family, and known target genes. cyp1a induction by PCB126 was enhanced in the Nrf2a mutants (156-fold in wildtypes vs. 228-fold in mutants exposed to 5 nM). Decreased expression of heme oxygenase (decycling) 1 (hmox1) in the Nrf2a mutants was accompanied by increased nrf2b expression. Target genes of Nrf2a and AhR2, NAD(P)H:quinone oxidoreductase 1 (nqo1) and glutathione S-transferase, alpha-like (gsta1), showed a 2-5-fold increase in expression in the Nrf2a mutants as compared to wildtype. This study elucidates the interaction between two important transcription factor pathways in the developmental toxicity of co-planar PCBs.
Collapse
Affiliation(s)
- Michelle E Rousseau
- Department of Environmental Health Sciences, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, United States.
| | - Karilyn E Sant
- Department of Environmental Health Sciences, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, United States.
| | - Linnea R Borden
- Department of Environmental Health Sciences, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, United States.
| | - Diana G Franks
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, United States.
| | - Mark E Hahn
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, United States.
| | - Alicia R Timme-Laragy
- Department of Environmental Health Sciences, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, United States; Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, United States.
| |
Collapse
|
13
|
Landrigan PJ, Wright RO, Cordero JF, Eaton DL, Goldstein BD, Hennig B, Maier RM, Ozonoff DM, Smith MT, Tukey RH. The NIEHS Superfund Research Program: 25 Years of Translational Research for Public Health. ENVIRONMENTAL HEALTH PERSPECTIVES 2015; 123:909-18. [PMID: 25978799 PMCID: PMC4590764 DOI: 10.1289/ehp.1409247] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 05/12/2015] [Indexed: 05/23/2023]
Abstract
BACKGROUND The Superfund Research Program (SRP) is an academically based, multidisciplinary, translational research program that for 25 years has sought scientific solutions to health and environmental problems associated with hazardous waste sites. SRP is coordinated by the National Institute of Environmental Health Sciences (NIEHS). It supports multi-project grants, undergraduate and postdoctoral training programs, individual research grants, and Small Business Innovation Research (SBIR) and Technology Transfer Research (STTR) grants. RESULTS SRP has had many successes: discovery of arsenic's toxicity to the developing human central nervous system; documentation of benzene toxicity to hematologic progenitor cells in human bone marrow; development of novel analytic techniques such as the luciferase expression assay and laser fragmentation fluorescence spectroscopy; demonstration that PCBs can cause developmental neurotoxicity at low levels and alter the genomic characteristics of sentinel animals; elucidation of the neurodevelopmental toxicity of organophosphate insecticides; documentation of links between antimicrobial agents and alterations in hormone response; discovery of biological mechanisms through which environmental chemicals may contribute to obesity, atherosclerosis, diabetes, and cancer; tracking the health and environmental effects of the attacks on the World Trade Center and Hurricane Katrina; and development of novel biological and engineering techniques to facilitate more efficient and lower-cost remediation of hazardous waste sites. CONCLUSION SRP must continue to address the legacy of hazardous waste in the United States, respond to new issues caused by rapid advances in technology, and train the next generation of leaders in environmental health science while recognizing that most of the world's worst toxic hot spots are now located in low- and middle-income countries.
Collapse
|
14
|
Benedetti M, Giuliani ME, Regoli F. Oxidative metabolism of chemical pollutants in marine organisms: molecular and biochemical biomarkers in environmental toxicology. Ann N Y Acad Sci 2015; 1340:8-19. [DOI: 10.1111/nyas.12698] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Maura Benedetti
- Dipartimento di Scienze della Vita e dell'Ambiente; Università Politecnica delle Marche; Ancona Italy
| | - Maria Elisa Giuliani
- Dipartimento di Scienze della Vita e dell'Ambiente; Università Politecnica delle Marche; Ancona Italy
| | - Francesco Regoli
- Dipartimento di Scienze della Vita e dell'Ambiente; Università Politecnica delle Marche; Ancona Italy
| |
Collapse
|
15
|
Reitzel AM, Karchner SI, Franks DG, Evans BR, Nacci D, Champlin D, Vieira VM, Hahn ME. Genetic variation at aryl hydrocarbon receptor (AHR) loci in populations of Atlantic killifish (Fundulus heteroclitus) inhabiting polluted and reference habitats. BMC Evol Biol 2014; 14:6. [PMID: 24422594 PMCID: PMC3899389 DOI: 10.1186/1471-2148-14-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 12/18/2013] [Indexed: 11/27/2022] Open
Abstract
Background The non-migratory killifish Fundulus heteroclitus inhabits clean and polluted environments interspersed throughout its range along the Atlantic coast of North America. Several populations of this species have successfully adapted to environments contaminated with toxic aromatic hydrocarbon pollutants such as polychlorinated biphenyls (PCBs). Previous studies suggest that the mechanism of resistance to these and other “dioxin-like compounds” (DLCs) may involve reduced signaling through the aryl hydrocarbon receptor (AHR) pathway. Here we investigated gene diversity and evidence for positive selection at three AHR-related loci (AHR1, AHR2, AHRR) in F. heteroclitus by comparing alleles from seven locations ranging over 600 km along the northeastern US, including extremely polluted and reference estuaries, with a focus on New Bedford Harbor (MA, USA), a PCB Superfund site, and nearby reference sites. Results We identified 98 single nucleotide polymorphisms within three AHR-related loci among all populations, including synonymous and nonsynonymous substitutions. Haplotype distributions were spatially segregated and F-statistics suggested strong population genetic structure at these loci, consistent with previous studies showing strong population genetic structure at other F. heteroclitus loci. Genetic diversity at these three loci was not significantly different in contaminated sites as compared to reference sites. However, for AHR2 the New Bedford Harbor population had significant FST values in comparison to the nearest reference populations. Tests for positive selection revealed ten nonsynonymous polymorphisms in AHR1 and four in AHR2. Four nonsynonymous SNPs in AHR1 and three in AHR2 showed large differences in base frequency between New Bedford Harbor and its reference site. Tests for isolation-by-distance revealed evidence for non-neutral change at the AHR2 locus. Conclusion Together, these data suggest that F. heteroclitus populations in reference and polluted sites have similar genetic diversity, providing no evidence for strong genetic bottlenecks for populations in polluted locations. However, the data provide evidence for genetic differentiation among sites, selection at specific nucleotides in AHR1 and AHR2, and specific AHR2 SNPs and haplotypes that are associated with the PCB-resistant phenotype in the New Bedford Harbor population. The results suggest that AHRs, and especially AHR2, may be important, recurring targets for selection in local adaptation to dioxin-like aromatic hydrocarbon contaminants.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Mark E Hahn
- Biology Department, Woods Hole Oceanographic Institution, 45 Water Street, Woods Hole, MA 02568, USA.
| |
Collapse
|
16
|
Whitehead A. Evolutionary Genomics of Environmental Pollution. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 781:321-37. [DOI: 10.1007/978-94-007-7347-9_16] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
|
17
|
Timme-Laragy AR, Goldstone JV, Imhoff BR, Stegeman JJ, Hahn ME, Hansen JM. Glutathione redox dynamics and expression of glutathione-related genes in the developing embryo. Free Radic Biol Med 2013; 65:89-101. [PMID: 23770340 PMCID: PMC3823629 DOI: 10.1016/j.freeradbiomed.2013.06.011] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 05/14/2013] [Accepted: 06/05/2013] [Indexed: 01/18/2023]
Abstract
Embryonic development involves dramatic changes in cell proliferation and differentiation that must be highly coordinated and tightly regulated. Cellular redox balance is critical for cell fate decisions, but it is susceptible to disruption by endogenous and exogenous sources of oxidative stress. The most abundant endogenous nonprotein antioxidant defense molecule is the tripeptide glutathione (γ-glutamylcysteinylglycine, GSH), but the ontogeny of GSH concentration and redox state during early life stages is poorly understood. Here, we describe the GSH redox dynamics during embryonic and early larval development (0-5 days postfertilization) in the zebrafish (Danio rerio), a model vertebrate embryo. We measured reduced and oxidized glutathione using HPLC and calculated the whole embryo total glutathione (GSHT) concentrations and redox potentials (Eh) over 0-120 h of zebrafish development (including mature oocytes, fertilization, midblastula transition, gastrulation, somitogenesis, pharyngula, prehatch embryos, and hatched eleutheroembryos). GSHT concentration doubled between 12h postfertilization (hpf) and hatching. The GSH Eh increased, becoming more oxidizing during the first 12h, and then oscillated around -190 mV through organogenesis, followed by a rapid change, associated with hatching, to a more negative (more reducing) Eh (-220 mV). After hatching, Eh stabilized and remained steady through 120 hpf. The dynamic changes in GSH redox status and concentration defined discrete windows of development: primary organogenesis, organ differentiation, and larval growth. We identified the set of zebrafish genes involved in the synthesis, utilization, and recycling of GSH, including several novel paralogs, and measured how expression of these genes changes during development. Ontogenic changes in the expression of GSH-related genes support the hypothesis that GSH redox state is tightly regulated early in development. This study provides a foundation for understanding the redox regulation of developmental signaling and investigating the effects of oxidative stress during embryogenesis.
Collapse
Affiliation(s)
- Alicia R. Timme-Laragy
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
- Division of Environmental Health, Department of Public Health, School of Public Health and Health Sciences, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - Jared V. Goldstone
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Barry R. Imhoff
- Division of Pulmonary, Allergy/Immunology, Cystic Fibrosis and Sleep, Department of Pediatrics, Emory University, Atlanta, GA, 30322, USA
| | - John J. Stegeman
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Mark E. Hahn
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Jason M. Hansen
- Division of Pulmonary, Allergy/Immunology, Cystic Fibrosis and Sleep, Department of Pediatrics, Emory University, Atlanta, GA, 30322, USA
| |
Collapse
|
18
|
Clark BW, Cooper EM, Stapleton HM, Di Giulio RT. Compound- and mixture-specific differences in resistance to polycyclic aromatic hydrocarbons and PCB-126 among Fundulus heteroclitus subpopulations throughout the Elizabeth River estuary (Virginia, USA). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:10556-66. [PMID: 24003986 PMCID: PMC4079253 DOI: 10.1021/es401604b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Atlantic killifish (Fundulus heteroclitus) inhabiting the Atlantic Wood Industries Superfund Site (Elizabeth River, Portsmouth, VA, USA) are resistant to the acute toxicity and cardiac teratogenesis caused by high levels of polycyclic aromatic hydrocarbons (PAHs) from creosote. The resistance is linked to down regulation of the aryl hydrocarbon receptor (AHR) pathway. We investigated the association between CYP1 activity, as a marker of potential AHR pathway suppression, and contaminant resistance in killifish subpopulations from sites throughout the estuary that varied significantly in PAH contamination level. Adult killifish and sediments were collected from seven sites across approximately 13.7 km in river length within the estuary and from a nearby reference site. Sediment PAH levels were determined using gas chromatography mass spectrometry. Embryos obtained via manual spawning were exposed to individual AHR agonists and PAH mixtures 24 h post fertilization (hpf); CYP1 activity was determined by in ovo ethoxyresorufin-o-deethylase (EROD) at 96 hpf, and cardiac deformity severity was scored at 144 hpf. The total PAH levels measured among the sites varied from approximately 200 to 125,000 ng/g dry sediment. Overall, the resistance to teratogenesis was strongest in the subpopulations from sites in or closest to the major PAH contamination sites, but even embryos from less-contaminated sites within the Elizabeth River demonstrated at least partial resistance to many challenges. Surprisingly, all of the subpopulations tested were highly resistant to PCB-126 (3,3',4,4',5-pentachlorobiphenyl). However, the degree of CYP1 activity response varied significantly among subpopulations and did not always correlate strongly with resistance to teratogenesis; some subpopulations resisted the cardiac teratogenesis caused by the challenges at doses that still elicited strong EROD induction. Our results suggest that there is variation in the adaptive phenotype exhibited by laboratory-spawned embryos from killifish subpopulations throughout the estuary. Furthermore, the results show that contaminants have affected killifish subpopulations throughout the estuary, even in sites with lower levels of PAHs.
Collapse
MESH Headings
- Abnormalities, Drug-Induced/enzymology
- Adaptation, Physiological
- Animals
- Cytochrome P-450 CYP1A1/metabolism
- Embryo, Nonmammalian/abnormalities
- Embryo, Nonmammalian/drug effects
- Embryo, Nonmammalian/enzymology
- Embryonic Development/drug effects
- Fundulidae/abnormalities
- Fundulidae/physiology
- Geologic Sediments/analysis
- Heart Defects, Congenital/chemically induced
- Heart Defects, Congenital/enzymology
- Polychlorinated Biphenyls/toxicity
- Polycyclic Aromatic Hydrocarbons/analysis
- Polycyclic Aromatic Hydrocarbons/toxicity
- Receptors, Aryl Hydrocarbon/metabolism
- Teratogens/analysis
- Teratogens/toxicity
- Virginia
- Water Pollutants, Chemical/analysis
- Water Pollutants, Chemical/toxicity
Collapse
Affiliation(s)
- Bryan W. Clark
- Nicholas School of the Environment, Levine Science Research Building, Duke University, Durham, NC, 27713, USA
- Corresponding author:
| | - Ellen M. Cooper
- Nicholas School of the Environment, Levine Science Research Building, Duke University, Durham, NC, 27713, USA
| | - Heather M. Stapleton
- Nicholas School of the Environment, Levine Science Research Building, Duke University, Durham, NC, 27713, USA
| | - Richard T. Di Giulio
- Nicholas School of the Environment, Levine Science Research Building, Duke University, Durham, NC, 27713, USA
| |
Collapse
|