• YAKHAK HOEJI
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• v.44 no.5
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• pp.416-423
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• 2000

There is a growing concern that a wide variety of chemicals released into the environment can disrupt the endocrine system of fish, wildlife and humans. Endocrine disrupting chemicals (EDCs) include pesticides such as DDT lindane and atrazine, the food packaging chemicals, phthalates and bisphenol A, alkylphenol ethoxylate detergents and the chemical industry by-products, dioxins. Xenoestrogens in the environment have been argued about health risk, because of estrogen mimetic chemicals are exposed only small amounts to human. A number of in vivo and in vitro assays are now in use to assess the activity of xenoestrogens in the environment. A human breast cancer cell line (MCF-7) was used to develop in vitro screening assay for the detection of xenoestrogenic environmental pollutants. The E-SCREEN (MCF7-BUS) assay is proposed as a reliable, easy and rapid-to-perform method. To optimize and validate this method before it can be used routinely, several phenol compounds and pesticides suspected to be estrogenic were tested using I-SCREEN assay. The results showed that this method is a valuable tool for screening potential estrogen-mimicking environmental pollutants and quantitative determination of estrogeniciy.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1999.05a
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• pp.61-61
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• 1999

• 대한생식의학회:학술대회논문집
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• 2004.06a
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• pp.92.1-92.1
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• 2004

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.156-157
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• 2003

In teleost, vitellogenin (Vtg) is synthesised in the liver in response to estrogens and transported by the blood to the growing oocytes where it is incorporated by micropincytosis (Selman and Wallace, 1982). Generally, Vtg is not induced in normal male fish but male fish are capable of synthesis Vtg in reponse to exogenous estrogen and xenoestrogens. (omitted)

• 대한생식의학회:학술대회논문집
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• 2002.11a
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• pp.83-83
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• 2002

• 대한생식의학회:학술대회논문집
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• 2002.11a
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• pp.84.2-85
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• 2002

• Journal of fish pathology
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• v.19 no.3
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• pp.189-195
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• 2006

A subtracted cDNA library of a marine scuticociliate, Philasterides dicentrarchii, in response to 17β-estradiol exposure was constructed using suppression subtractive hybridization (SSH). As a result of SSH, 275 clones were isolated, and among them, only glutathione peroxidase (GPX) gene was isolated as an antioxidative enzyme responding to 17β-estradiol. The semi-quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) analysis revealed that the transcription of GPX gene of P. dicentrarchii was clearly increased by exposure to 17β-estradiol. The GPX transcription was also clearly increased by exposure to xenoestrogens such as bisphenol A (BPA) and genistein.

• Environmental Analysis Health and Toxicology
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• v.19 no.3
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• pp.251-259
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• 2004

Xenoestrogens are chemicals with diverse structure that mimic estrogen. Bisphenol A, a monomer of polycarbonate and epoxy resins, has been detected in canned food and human saliva. Bisphenol A stimulate cell proliferation and induce expression of estrogen -response genes in vitro. The purpose of the this study was to evaluate cell proliferation of bisphenol A in the presence of a rat liver 59 mix contaning cytochrome P450 enzymes and Cu (II). The fragmentation of intact DNA, a parameter of apoptotic cell death, was evaluated quantitatively by diphenylamine reaction method. Bisphenol A induced apoptotic cell death in a dose-dependent manner The effect of radical scavenger on the apoptotic cell death induced bisphenol A was investigated. The DNA fragmentation induced by bisphenol A was significantly inhibited by addition of radical scavenger to the culture medium. This indicated that elevated oxidative stress caused by imbalance between the production and removal of free radicals occurred in cells. Taken together, these results suggest that free radical reacts with Cu (II) leading oxidative stress.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.31-31
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• 2003

The incidence of reproductive abnormalities in the male has been reported to have increased during the past 50 years. These changes may be attributable to the presence of chemical with oestrogenic activity in our environment. Present study was carried out to determine the effects of maternal exposure to xenoestrogens on the testicular development and on the transcriptional expression of the steroidogenic enzyme and subunits of inhibin/activin in testis of male offspring. Pregnant female mice were administrated with 4-tert-octylphenol (OP; 2, 20, 200mg/kg), Bisphenol A (BPA; 2, 20, 200$\mu\textrm{g}$/kg), $\beta$-estradiol 17-valerate (EV; 2$\mu\textrm{g}$/kg) or vehicle (CV; corn oil) during gestational days 11 to 17. Offsprings were sacrificed on gestational day 18 (fetal 18) and neonatal day 7. Body weights were significantly increased in groups treated with all doses of OP and BPA. Maximum seminiferous tubules diameter on gestational day 18 were not changed in any treatment group, however, they were significantly increased on the neonatal day 7 in the group treated with low-dose of OP (2 mg/kg) and BPA (2 $\mu\textrm{g}$/kg). Increased expression of the P450$_{17a}$-hydroxylase dehydrogenase (P450$_{17a}$), 3$\beta$-hydroxylase dehydrogenase (3$\beta$-HSD), and 17$\beta$-hydroxylase dehydrogenase (17$\beta$-HSD) on gestational day 18 were observed in the groups treated with 2 or 20 mg/kg of OP. However, expression of the steroidogenic enzymes were not changed in the groups treated with all the doses of BPA. In contrast with the results from fetal testis, no expressional changes of these enzymes was found in all the OP-treated group and increased expression of inhibin/activin $\beta$B subunit mRNA were obseued in the 200 $\mu\textrm{g}$/kg BPA-treated group in the neonatal day 7. These results suggest that gestational exposure to low level of xenoestrogen causes a stimulatory effects on the transcriptional expressions of steroidogenic enzymes and subunits of inhibin/activin and on the seminiferous tubule development by their estrogen-like actions.ons.

• Toxicological Research
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• v.16 no.4
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• pp.285-291
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• 2000

So far, investigation of environmental pollution has been achieved in field study. This remains the most exhaustive approach, current dimensions of environmental researches and their inherent complexity require that relatively inexpensive and simple laboratory procedures are developed to make possible the screening of large numbers of sites and samples. At this point. microbioassay has been high-lighted. The purpose of this study is to evaluate the water pollution using microbioassay. Two microbioassay methods were optimized and validated for the sensitive and quantitative determination of total toxic effects in the water. EROD(Ethoxyresorufin-O-deethylase) microbioassay was focused to detect PARs, PCBs and dioxinlike components in the water and E-screen assay to xenoestrogens. The EROD microbioassay was executed in rat hepatoma cell line, H4IIE and E-screen assay in MCF7-BUS cell line. Kumho river was selected for this study. 5ι of river water was extracted using combined solid-phase extraction in static adsorption mode with soxhlet extraction. Pollutants adsorbed to the XAD-4 resin were recovered by elution with ethyl acetate and methylene chloride (1 : 9). Toxic effects of extracts were determined by EROD-microbioassay and E-screen assay. EROD activities of water samples were 7.24-72.24 ng/ι MEQ. The estrogenic effect of various water samples is quantitatively evaluated by EEQ. The EEQ of samples range from 0.05 to 6.07 ng-EEQ/ι. These results suggested that Kumho river was highly polluted with organic toxic chemicals.