In House Validation Of A Recombinant Yeast Estrogen And Androgen Receptor Agonist And Antagonist Screening Assays.
Summary of "In House Validation Of A Recombinant Yeast Estrogen And Androgen Receptor Agonist And Antagonist Screening Assays."
Besides other modes of action, endocrine disruptors may interact with hormone receptors thereby modifying the physiological function of endogenous hormones. In the present study we report the results obtained with yeast based assays to detect the (anti-)estrogenic potential (YES) and the (anti-)androgenic potential (YAS) of 105 substances. The results show very high reproducibility and good concordance with literature data of in vivo and/ or in vitro studies: the overall true positive rate, specificity, and accuracy of the assays were 78%, 95%, and 87% (estrogen agonism), and 70%, 97%, and 90% (estrogen antagonism), 88%, 96%, and 95% (androgen agonism) and 81%, 88%, and 85% (androgen antagonism). Furthermore, the performance of the YES assay has been compared to the HeLa based transcriptional activation assay using 20 compounds. The overall true positive rate, true negative rate, and accuracy obtained for the 20 compounds were 100%, 88%, and 95% (mammalian cell based HeLa assay) and 92%, 86%, and 90% (yeast based YES assay). Taken together, the YES and YAS are robust systems, easy to handle and satisfying the requirements for screening systems that can be applied in programs including the US Environmental Protection Agency's Endocrine Disruptor Screening Program.
BASF SE, Experimental Toxicology and Ecology, Z 470 D-67056 Ludwigshafen, Germany.
This article was published in the following journal.
Name: Toxicology in vitro : an international journal published in association with BIBRA
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/20732407
- DOI: http://dx.doi.org/10.1016/j.tiv.2010.08.008
Medical and Biotech [MESH] Definitions
Selective Estrogen Receptor Modulators
A structurally diverse group of compounds distinguished from ESTROGENS by their ability to bind and activate ESTROGEN RECEPTORS but act as either an agonist or antagonist depending on the tissue type and hormonal milieu. They are classified as either first generation because they demonstrate estrogen agonist properties in the ENDOMETRIUM or second generation based on their patterns of tissue specificity. (Horm Res 1997;48:155-63)
A second generation selective estrogen receptor modulator (SERM) used to prevent osteoporosis in postmenopausal women. It has estrogen agonist effects on bone and cholesterol metabolism but behaves as a complete estrogen antagonist on mammary gland and uterine tissue.
A first generation selective estrogen receptor modulator (SERM). Like TAMOXIFEN, it is an estrogen agonist for bone tissue and cholesterol metabolism but is antagonistic on mammary and uterine tissue.
Estrogen Receptor Alpha
One of the ESTROGEN RECEPTORS that has marked affinity for ESTRADIOL. Its expression and function differs from, and in some ways opposes, ESTROGEN RECEPTOR BETA.
A familial form of PSEUDOHERMAPHRODITISM transmitted as an X-linked recessive trait. These patients have a karyotype of 46,XY with end-organ resistance to androgen due to mutations in the androgen receptor (RECEPTORS, ANDROGEN) gene. Severity of the defect in receptor quantity or quality correlates with their phenotypes. In these genetic males, the phenotypic spectrum ranges from those with normal female external genitalia, through those with genital ambiguity as in Reifenstein Syndrome, to that of a normal male with INFERTILITY.
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