title: Temporal patterns of induction and recovery of biomarker transcriptional responses to 4-Nonylphenol and 17β-estradiol in the estuarine arrow goby, Clevelandia ios.
abstract: Several estuaries along the Pacific Ocean coast of North America were identified recently as having elevated 4-nonylphenol (4-NP) in sediments and biota, raising concerns about reproductive impacts for wildlife given 4-NP's established estrogenic activity as an endocrine-disrupting compound. Here we characterize 4-NP mediated induction and recovery of estrogen-sensitive gene transcripts in the arrow goby (Clevelandia ios), an intertidal fish abundant in estuarine mud flats on the west coast of North America. Male gobies were exposed to waterborne 4-NP at 10 μg/L or 100 μg/L for 20 days followed by a 20 day depuration period. Additional males were treated with 17β-estradiol (E2; 50 ng/L). 4-NP at 100 μg/L elevated hepatic mRNAs encoding vitellogenins A (vtgA) and C (vtgC) and choriogenin L (chgL) within 72 h, and choriogenin H minor (chgHm) within 12 days. Hepatic mRNAs encoding estrogen receptor alpha (esr1) were also elevated after 12 days of 4-NP exposure, but returned to pre-exposure levels at 20 days even under continuing 4-NP treatment. 4-NP did not alter mRNA levels of estrogen receptor gamma (esr2a) in the liver, or of esr1, esr2a, and cytochrome P450 aromatase B (cyp19a1b) in the brain. The temporal pattern of initial induction for hepatic vtgA, vtgC, and chgL transcripts by 4-NP mirrored the pattern by E2, while chgHm and esr1 mRNA induction by 4-NP lagged 2-11 days behind the responses of these transcripts to E2. These findings establish 4-NP concentration- and time-dependent induction patterns of choriogenin and vitellogenin transcription following exposure to environmentally relevant 4-NP concentrations, while concurrently demonstrating tissue-specific induction patterns for esr1 by estrogenic compounds. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1513-1529, 2017.
authors.affiliation: Biological Sciences Department, Center for Coastal Marine Sciences, California Polytechnic State University, San Luis Obispo, California, 93407, USA.
authors.forename: Kaitlin M
authors.initials: KM
authors.lastname: Johnson
authors.affiliation: Biological Sciences Department, Center for Coastal Marine Sciences, California Polytechnic State University, San Luis Obispo, California, 93407, USA.
authors.forename: Sean C
authors.initials: SC
authors.lastname: Lema
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D052244:Endocrine Disruptors / Q000494:pharmacology*; D004958:Estradiol / Q000494:pharmacology*; D063366:Estuaries; D005260:Female; D005399:Fishes / Q000235:genetics / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D010636:Phenols / Q000494:pharmacology*; D013997:Time Factors; D014819:Vitellogenins / Q000235:genetics; D014874:Water Pollutants, Chemical / Q000494:pharmacology*
chemical_list: D015415:Biomarkers; D052244:Endocrine Disruptors; D010636:Phenols; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D004958:Estradiol; C041594:4-nonylphenol
keywords: biomarker; choriogenin; endocrine disruption; estradiol; estrogen receptor; estuary; fish; nonylphenol; vitellogenin; xenoestrogen