Estrogenic effects of environmental chemicals: an interspecies comparison.

Abstract

The development of various in vitro screening methods has led to identification of novel estrogenic chemicals of natural and anthropogenic origin. In this study, the (anti)estrogenic potential of several environmental chemicals were compared in an array of in vitro test systems comprising: (i) competitive binding to estrogen receptors derived from the human breast cancer cell line MCF-7 (hER) and rainbow trout (Oncorhynchus mykiss) (rtER), (ii) a proliferation assay with MCF-7 cells (E-SCREEN), and iii) induction of vitellogenin (rtVtg) in isolated rainbow trout hepatocytes. The results showed substantial differences in assay sensitivity for potent estrogens like 17beta-estradiol, diethylstilbestrol and zearalenone (ranking order of sensitivity: E-SCREEN > hER approximately rtER approximately rtVtg). Chemicals like 4-n-nonylphenol and bisphenol A had higher relative binding affinity to the hER, whereas 4-t-butylphenol and 4-n-butylphenol showed highest affinity to the rtER. Zearalenone and the novel estrogen 4-t-butylhexanol displayed a considerable higher relative potency in the E-SCREEN than the rtVtg assay, whereas alkylphenols and the novel estrogen mimic 4-t-butyl-nitrobenzene were most potent in fish cells. Correlation analysis of data from the test systems suggest that interspecies differences is largely due to inter-assay variation of the ER-dependent cellular responses, whereas binding to the ER are fairly similar in the two species tested.

• Authors: Christel M Olsen, Elise T M Meussen-Elholm, Jan K Hongslo, Jørgen Stenersen, Knut-Erik Tollefsen
• Journal: Comparative biochemistry and physiology. Toxicology & pharmacology : CBP (Comp Biochem Physiol C Toxicol Pharmacol) Vol. 141 Issue 3 Pg. 267-74 (Jul 2005) ISSN: 1532-0456 [Print] United States
• PMID: 16099220 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Environmental Pollutants
• Estrogens, Non-Steroidal
• Receptors, Estrogen
• Vitellogenins

Topics

• Animals
• Binding, Competitive (drug effects)
• Biological Assay
• Breast Neoplasms (pathology)
• Cell Line, Tumor
• Cell Proliferation (drug effects)
• Dose-Response Relationship, Drug
• Environmental Monitoring (methods)
• Environmental Pollutants (metabolism, toxicity)
• Estrogens, Non-Steroidal (metabolism, toxicity)
• Hepatocytes (drug effects, metabolism)
• Humans
• Liver (drug effects, metabolism)
• Oncorhynchus mykiss
• Receptors, Estrogen (drug effects, metabolism)
• Species Specificity
• Vitellogenins (metabolism)