Document Detail

Induction of hepatic cytochrome P4501A1/2B activity and disruption of thyroglobulin synthesis/secretion by mono-ortho polychlorinated biphenyl and its hydroxylated metabolites in rat cell lines.
MedLine Citation:
PMID:  18092871     Owner:  NLM     Status:  MEDLINE    
As the active metabolites of polychlorinated biphenyl (PCBs), hydroxylated polychlorinated biphenyls (OH-PCBs) are found in wildlife and human tissues. They have been proposed as main contributors for endocrine disruption of PCBs in living organisms. In this study, mono-ortho PCB 156 and its hydroxylated metabolites 4'-OH-PCB 159, 4'-OH-PCB 121, and 4'-OH-PCB 72 were selected to investigate the toxic effects on rat hepatoma H4IIE cell line and rat thyroid follicle FRTL-5 cell line at concentrations of 1, 10(2), 10(4) nM. 7-Ethoxyresorufin-O-deethylase (EROD) and 7-pentoxyresorufin-O-dealkylase (PROD) activities were determined with micro-EROD/PROD to indicate cytochrome P4501A1 (CYP1A1) and cytochrome P4502B (CYP2B) induction in the H4IIE cell after exposure for 72 h. To assess thyroid disruption of these compounds, thyroglobulin concentrations also were detected inside FRTL-5 cell with immunocellularchemistry and in its medium with radioimmunoassay after exposure for 24 h. Significant inductions of EROD activity by PCB156 at 10(2) and 10(4) nM (p < 0.05) were observed, but no effects by the three OH-PCBs in H4IIE cell line. 7-Pentoxyresorufin-O-dealkylase activities were induced only by 10(4) nM of PCB156 and the three OH-PCBs (p < 0.05). Meanwhile, significant increases of thyroglobulin concentrations were observed in the medium of FRTL-5 cell exposed to 4'-OH-PCB 121 and 4'-OH-PCB 72 at all of the test concentrations (p < 0.05), but not to the other compounds. The results demonstrated that mono-ortho PCBs mainly could be metabolized to hydroxylated metabolites through CYP1A1 instead of CYP2B. Moreover, after being metabolized, OH-PCBs still sustained the ability to induce PROD activity and did exhibit the disruption on thyroglobulin synthesis/excretion in rat cells.
Fangxing Yang; Ying Xu; Hongmei Pan; Desheng Wu
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Environmental toxicology and chemistry / SETAC     Volume:  27     ISSN:  0730-7268     ISO Abbreviation:  Environ. Toxicol. Chem.     Publication Date:  2008 Jan 
Date Detail:
Created Date:  2007-12-20     Completed Date:  2008-03-06     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8308958     Medline TA:  Environ Toxicol Chem     Country:  United States    
Other Details:
Languages:  eng     Pagination:  220-5     Citation Subset:  IM    
State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, People's Republic of China.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Cell Line
Cell Line, Tumor
Cytochrome P-450 CYP1A1 / drug effects*,  metabolism
Cytochrome P-450 CYP2B1 / drug effects*,  metabolism
Dose-Response Relationship, Drug
Endocrine Disruptors / pharmacology
Liver / enzymology
Polychlorinated Biphenyls / metabolism,  pharmacology*
Thyroglobulin / biosynthesis*,  secretion
Reg. No./Substance:
0/Endocrine Disruptors; 0/Polychlorinated Biphenyls; 9010-34-8/Thyroglobulin; EC P-450 CYP1A1; EC P-450 CYP2B1

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Distribution of polycyclic musks in surface sediments from the Pearl River Delta and Macao Coastal R...
Next Document:  Modeling polycyclic aromatic hydrocarbon composition profiles of sources and receptors in the Pear R...