Androgenicity assay

A -Testosterone (S-63) and A -Sa-dibydrotestosterone (D-48) show increased androgenic and anabolic activities in the rat when administered orally and decreased activities when administered subcutaneously. Chick comb assays for androgenic activity show that the A -compounds are more active than their parent compounds. However, in the mouse androgen assay A -5a-dihydrotestosterone is more active and A -testosterone is less active than their parent compounds. 

To review the androgen assays using LC-MS published during the last five years, many papers were concerned with prostate cancer (PCa) and benign prostate hyperplasia PCa is the most common... 

Androgen receptor binding/Reporter gene assay. 

Kim SS, Kwack SJ, Lee RD et al (2005) Assessment of estrogenic and androgenic activities of tetramethrin in vitro and in vivo assays. J Toxicol Environ Health A 68 2277-2289... 

Yamada T, Ueda S, Yoshioka K et al (2003) Lack of estrogenic or (anti-)androgenic effects of d-phenothrin in the uterotropic and Hershberger assays. Toxicology 186 227-239... 

Kunimatsu T, Yamada T, Ose K et al (2002) Lack of (anti-)androgenic or estrogenic effects of three pyrethroids (esfenvalerate, fenvalerate, and permethrin) in the Hershberger and uterotrophic assays. Regul Toxicol Pharmacol 35 227-237... 

Hormones Androgens Testosterone Testosterone EIA kit Salivary assay test Colorimetric EIA kit Testosterone ELISA kit Immunometric Ltd. Salim etric Assay Designs Inc. Oxford Biomedical Research http //www.oxfordbiomed.com/... 

A variety of immunoassay test kits for androgens are available from commercial sources. Table 4 indicates some of the most important companies commercializing these assays. 

These data indicate that hydrophobic chemicals with estrogenic and EROD-inducing potential are widespread in this ecosystem and are readily bioavailable to aquatic organisms living in the system. By incorporating the YES, the recently developed yeast androgen screen, and the EROD assays (Rastall, 2004b) into exposure assessment approaches, a more complete picture of the potential toxicity... 

Endogenous and exogenous androgens can be derivatized with trimethylsilyl (TMS) for hydroxy functions and by 0-methylation for ketones, and analyzed with GC-FID or GC-MS (Shimada et al., 2001). MS is more prevalent due to unequivocal identification and greatly increased sensitivity but FID is still used in laboratories for some steroids. Sterols have typically been analyzed by GC-FID and GC-MS with derivatization to optimize peak shape (Shimada et al., 2001), and bile acids can be derivatized with M-butyl ester-TMS ether and analyzed by GC-FID from plasma samples (Batta et al., 1998). Juricskay and Telegdy (2000) reported an assay capable of analyzing 28 steroids in urine samples using GC-FID. 

Newly proposed test guidelines to specifically address effects on hormone homeostasis and on male and female reproductive organs include the rodent uterotrophic assay to detect estrogenic effects (OECD 2007a) and the rodent Hershberger assay to detect androgenic effects (OECD 2007b). 

The Tier 2 testing assays are intended to confirm, characterize, and quantify effects for estrogen, androgen, and thyroid active substances. The EDSTAC selected Tier 2 to include the most sensitive developmental Ufestage, to identify the specific hazard caused by the chemical and establish a dose-response relationship, and to include a range of taxa. The Tier 2 screening assays under consideration by the US-EPA are summarized in Table 4.22. 

Anti-androgenic effect. Sterol fraction of the dried fruit, in cell culture, was active on CA-PC3 and reduced androgen-induced reporter gene expression in transcriptional assay IC50 50 pg/mL . Administration to... 

Blankvoort, B.M.G., Richard, J.T., Rodenburg, Murk, A.J., Koeman, J.H., Schilt, R., Aarts, M.M.J.G. (2005). Androgenic activity in surface water samples detected using the AR-LUX assay indications for mixture effects. Environmental Toxicology and Pharmacology 19, 263-272. 

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