• Toxicological Research
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• 제22권1호
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• pp.15-22
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• 2006

Many of endocrine disrupting chemicals induce effects via interaction with hormone receptors and responsive elements in target cells. We investigated endocrine disrupting effects of some food additives and contaminants including BHA, BHT, ethoxyquin, propionic acid, sorbic acid, benzoic acid, CPM, aflatoxin B1, cadmium chloride, genistein, TCDD and PCBs in yeast transformants expressing human steroid hormone receptors along with steroid responsive elements. The response limit of genetically recombinant yeast to $17{\beta}$-estradiol, testosterone and progesterone was $1{\times}10^{-16},\;1{\times}10^{-12}\;and\;1{\times}10^{-13}M$, respectively. BHT induced weak transcriptional activity in estrogen sensitive yeast, while BHA and sorbic acid interacted weakly with androgen receptor/responsive element. CPM induced transcriptional activities in all types of yeasts sensitive to steroid hormones. Zearalenone and genistein induced high transcriptional activation in estrogen sensitive yeast with relative potencies almost $10^8$ folds lower than $17{\beta}$-estradiol. TCDD induced transcriptional activation weakly in estrogen- and progesterone- sensitive yeasts. This study elucidated that recombinant yeast is a sensitive and high-throughput system and can be used for the direct assessment on chemical interactions with steroid receptors and responsive elements. Also, the present study raises the requirement of evaluation on the endocrine disrupting effects of BHT, BHA, sorbic acid, CPM and TCDD for their transcription activity in yeast screening system though weak in intensity.

• Toxicological Research
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• 제20권3호
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• pp.205-211
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• 2004

Concern that some chemicals in our environment may affect human health by disrupt-ing normal endocrine function has prompted a research on interactions of environmental contaminants with steroid hormone receptor. Toxaphene and chlordane are among the 12 persistent organic pollutants identified by the United Nations Environment Programme as requiring urgent attention. We compared the estrogenic activity of two organochlorine pesticides, toxaphene and chlordane, at estrogen receptor a (ER$\alpha$) and estrogen receptor $\beta$ (ER$\beta$). Human hepatoma cells (HepG2) were transiently transfected with rat ER$\alpha$ or ER$\beta$ plus an estrogen-responsive complement C3-luciferase (C3-Luc) reporter gene. After transfection, cells were treated with various concentrations of toxaphene and chlordane to investigate agonism or antagonism of these chemicals. Both toxaphene and chlordane were potent agonists in HepG2 cells for ER$\alpha$. In contrast, these chemicals had a minimal agonist activity with ER$\beta$ and almost abolished 17$\beta$-estradiol-induced ER$\beta$-mediated activity. Therefore, toxaphene and chlordane behaved as an ER$\alpha$ agonist and an ER$\beta$ antagonist with estrogen-responsive reporter plasmid C3-Luc, and exposure to these organochlorine pesticides could have a crictical effect on normal endocrine function.

• Toxicological Research
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• 제21권4호
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• pp.333-338
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• 2005

Many of thyroid hormones disrupting chemicals induce effects via interaction with thyroid hormone and retinoic acid receptors and responsive elements intrinsic in target cells. We studied thyroid hormones disrupting effects of food additives and contaminants including BHA, BHT, ethoxyquin, propionic acid, sorbic acid, benzoic acid, CPM, aflatoxin B1, cadmium chloride, genistein, TCDD, PCBs and TDBE in recombinant HeLa cells containing plasmid construct for thyroxin responsive elements. The limit of response of the recombinant cells to T3 and T4 was $1\times10^{-12}\;M$. BHA. genistein, cadmium and TBDE were interacted with thyroid receptors with dose-responsive pattern. In addition, BHA, BHT, ethoxyquin, propionic acid, benzoic acid, sorbic acid, and TBDE showed synergism while cadmium chloride antagonism for T3-induced activity. This study elucidates that recombinant HeLa cell is sensitive and high-throughput system for the detection of chemicals that induce thyroid hormonal disruption via thyroid hormone receptors and responsive elements. Also this study raised suspect of BHA. BHT, ethoxyquin, propionic acid, benzoic acid, sorbic acid, TBDE, genisteine and cadmium chloride as thyroid hormonal system disruptors.

• 한국동물생명공학회지
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• 제37권4호
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• pp.276-284
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• 2022

Endocrine-disrupting chemicals found in many commercial products may interfere with the normal functioning of the endocrine system and are unsafe because of their cumulative effect on the human body. However, little is known about the effects of combinations of endocrine-disrupting chemicals in humans. Methoxychlor and bisphenol A are toxic to male reproductive organs. Therefore, we studied the effects of methoxychlor and bisphenol A on male reproductive function. Male mice were divided into four treatment groups: control, 400 mg methoxychlor, 1 mg bisphenol A, and 400 mg methoxychlor + 1 mg bisphenol A/kg/day. Methoxychlor and bisphenol A were dissolved in sesame oil and acetone and administered orally for 4 weeks. After administration, the weight and histological changes in the testicles and epididymis, sperm count and health were observed biochemical tests and whole blood counts were performed. The results showed that the mice in the bisphenol A and methoxychlor + bisphenol A groups gained more weight than those in the control and methoxychlor group. The weights of the testes and epididymis were higher in the experimental groups than in the control. Sperm motility and progression were significantly reduced in the bisphenol A and methoxychlor + bisphenol A groups. Histological observation showed a reduced number of sperm, smaller seminiferous tubules, and destroyed lumen in the methoxychlor + bisphenol A group compared to the other groups. In conclusion, our study showed that methoxychlor and bisphenol A destroy male reproductive tissues and decrease sperm quality.

• 한국발생생물학회지:발생과생식
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• 제4권1호
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• pp.53-59
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• 2000

내분비계 장애물질은 생체내에서 호르몬 등의 내분비계에 영향을 주기 때문에 미량으로도 생식기능에 이상을 가져 올 수 있고, 급ㆍ만성 독성과는 달리 차세대에 그 영향이 발현될 수 있다. 대부분의 내분비계 장애물질은 에스트로겐 유사물질로 알려져 있으며, 내분비계 장애물질의 하나인 bisphenol A (BPA)도 이러한 성질을 가진 물질이다. 본 연구는 BPA가 생쥐의 정자형성과정에 어떤 영향을 미치는가를 분석하고자, 농도별 (저농도, 20 mg/kg, 고농도 200 mg/kg) 구강투여를 실시하였다. 정자수와 테스토스테론 농도 및 산자수가 대조군에 비해 처리군에서 점진적으로 감소하는 경향을 보였으며, 산자수에서 유의적인 차이(P<0.01)를 나타내었다. 특히 국부적이긴 하지만 세정관 내강에서의 정자세포 소실 양상은 정자수의 감소 원인으로 사료된다. 성성숙 이후 정소에서의 발현이 소실되는 것으로 알려진 TGF-$\beta$계에서는 TGF-$\beta$1이 고농도의 BPA투여시 발현되었지만, 그 외의 리간드와 수용체의 발현은 관찰되지 못했다. 결론적으로 고농도의 BPA노출은 웅성생식계에 영향을 미칠 수 있으며, 이는 정자형성에 장애를 일으켜 불임을 유발할 수도 있을 것으로 보여진다.

• Biomolecules & Therapeutics
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• 제8권2호
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• pp.147-152
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• 2000

The rodent uterotrophic assay is currently recommended as one of the primary in vivo assays far endocrine disrupting chemicals by the Organization for Economic Cooperation and Development (OECD) and Endocrine Disruptor Screening and Testing Advisory Committee (US EPA EDSTAC). Generally, this assay relies on the rapid increase in uterus and vagina weights when exposed to estrogenic compounds. Phthalate esters have been used extensively as a plasticizer in the manufacture of plastic products such as PVC films and medical devices. Recently, phthalate esters have been shown to induce endocrine system mediated responses. However, a flew studies have been conducted for the screening of their estrogenic activity. In this study the estrogenic activity of seven phthalate esters, butyl benzyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), di-n-butylphthalate (DBP), diethylphthalate (DEP), di-n-pentylphthalate (DPF), di-n-propylphthalate (DPrP) and dicyclohexylphthalate (DCHP), was examined in uterotrophic assay. Phthalate esters dissolved in corn oil were administered to ovariectomized (OVX) female Sprague-Dawley rats by sub-cutaneous injection for three consecutive days. fiats were sacrificed 24h after final treatment, and then uterus and vagina weights were deter mined. All phthalate esters tested in this assay did not change talc uterus and vagina weights at dosage levels up to 200 mg/kg/day treatment. These results demonstrated that phthalate esters did not exhibit estrogenic activity in vivo uterotrophic assay.

• 생태와환경
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• 제36권2호통권103호
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• pp.97-107
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• 2003

어류 vitellogenin은 난황전구체로 난형성과정동안에 estradiol의 체내 순환에 의해 암컷의 간에서 생산되며 alkylphenol류와 같은 비이온성 계면활성제 등의 내분비계 장애물질에 의해 수컷에서도 생산된다. 물 환경의주요 생물종인 어류는 내분비계장애물질에 의해 암컷에서는 번식률 저하와 함께 수컷에서는 정소의 축소 및 이에 따른 암컷화가 관찰된다. 특히 수컷에서 내분비계 장애물질에 의해 유도된 vitellogenin의 생성을 이용하여 환경오염에 의해 유도된 생물체의 유전자 발현 변화 뿐만 아니라 이를 토대로 특정지역의 환경오염을 모니터링할 수 있다. 본 논문에서는 어류의 vitetlogenin를 이용하여 수환경의 내분비계장애물질의 검출과 환경오염모니터링을 위한 biomarker로서의 유용성을 검토하였다.

• 한국환경성돌연변이발암원학회지
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• 제22권4호
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• pp.259-265
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• 2002

Phthalate analogues are a plasticizer and solvent used in industry. Phthalates were reported to be a potential carcinogen classified in the category of suspected endocrine disruptors. Most common human exposure to these compounds may occur with contaminated food. They may migrate into food from plastic wrap or may enter food from general environmental contamination. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of phthalates that possibly threaten the public health. Concern about their use has been mounting. To screen and elucidate the endocrine disrupting activity and their mechanism of phthalate analogues, first of all, E-screen assay was performed in MCF7 human breast cancer cells with seven phthalate analogues. In this cell proliferation assay, only dibutyl phthalate (DBP) showed weak estrogenic activity. Also the yeast-based transcription assay to assess the interactions of DBP with the estrogen, androgen, and progesterone receptors was conducted. DBP in the concentration ranges from 10$^{-16}$ to 10$^{-11}$ M was active in the estrogen transcriptional assay, but it did not show the effect on $\beta$-galactosidase activity in the progesterone and androgen transcriptional assays. These data indicate that DBP shows estrogenic potential and can be classified as weak and/or suspected endocrine disrupting chemicals.

• 농약과학회지
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• 제12권4호
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• pp.342-350
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• 2008

최근 내분비장애 추정물질의 분류를 위해 많은 시험법이 연구되고 있으며 미국 EPA와 OECD에서는 시험법을 설정하려고 노력하고 있다. 추후 기등록농약에 대한 자료요구 또는 신규 등록농약 적용 등록기준의 추가 등을 고려하여 내분비계장애 추정물질 관련 OECD와 EPA에서 권장하는 시험법을 확립하고자 본 연구를 수행하였다. 시험약제를 30일간 경구 투여하여 조사한 결과, metribuzin 투여 수컷에서 부고환, 전립선, 정낭의 중량이 증가하였고 갑상선에서는 유의한 중량변화가 나타나지 않았다. 암컷에서는 갑상선의 중량 감소가 나타난 반면에 생식장기 중량에는 유의적인 변화가 없었다. Metribuzin 투여수컷에서 testosterone이 100 mg/kg/day 처리수준에서 감소하였고 FT4가 50, 100 mg/kg 수준에서 증가하였다. 암컷에서는 T3가 50, 100 mg/kg/day 수준에서 증가하여 갑상선 호르몬에 영향이 나타나는 것을 볼 수 있었다. 시험세포를 이용한 시험결과, 시험약제를 1 nM에서 1,000 nM까지 처리하였을 때 음성대조군과 비교할 때 metribuzin은 106-122%의 영향을 나타내어 세포이용시험에서는 metribuzin이 갑상선 호르몬성 영향을 보인 것으로 나타났다. 항갑상선 호르몬성 영향 시험에서는 시험약제 100 nM과 T4의 혼합 처리시 metribuzin은 양성 대조군과 비교하여 감소하여 항갑상선 호르몬성 영향을 나타내었다. 본 시험을 통하여 OECD TG 407과 EDSTAC에서 권고하는 pubertal assay와 수의과학 검역원에서 제조한 HeLaTRE cell을 이용한 in vitro 시험이 갑상선 호르몬성 영향 검색 시험으로 활용될 가능성이 있는 것으로 사료되었다.

• 농약과학회지
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• 제12권3호
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• pp.207-214
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• 2008

내분비장애 추정물질의 분류를 위해 많은 시험법이 연구되고 있는데 추후 내분비장애 추정물질로 분류된 기등록 농약에 대한 자료요구 또는 신규 등록농약에 대한 등록기준의 추가 등을 고려하여 OECD와 EPA에서 권장하는 시험법을 확립하고자 본 연구를 수행하였다. 시험약제를 30일간 경구 투여하여 조사한 결과, alachlor 투여 수컷에서 25 mg/kg/day, 50 mg/kg/day에서 고환과 갑성선의 중량이 증가하였다. Alachlor 투여 암컷에서는 질의 중량이 25, 50 mg/kg/day에서 감소하였고 25 mg/kg/day에서 갑상선의 중량이 감소하였다. Alachlor 투여 암컷 25, 50 mg/kg/day에서 주요 갑상선 호르몬인 T4와 성호르몬 testosterone이 감소하였다. 따라서 pubertal assay 결과 alachlor는 갑상선 호르몬성 영향이 의심되었다. 시험세포를 이용한 시험 결과, 시험약제를 1 nM에서 1000 nM까지 처리하였을 때 음성대조군과 비교하여 alachlor는 100-134%의 갑상선 호르몬성 영향을 나타내었다. 따라서 세포를 이용한 시험에서는 alachlor에 의한 갑상선 호르몬성 영향이 나타나는 것으로 판단되었다. 항갑상선 호르몬성 영향 시험에서는 시험약제 100 nM과 T4의 혼합 처리시 alachlor는 항갑상선 호르몬성 영향은 나타나지 않았다.