• 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.

• 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.

• Toxicological Research
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• 제18권4호
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• pp.331-339
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• 2002

Phenoxy compounds, 2,4-Dichlorophenol acetoxy acid (2,4-D) and 2,4-dichlorophenol (DCP), are widely used as a hormonal herbicide and intermediate for pesticide manufacturing, respectively. In order to assess the potential of these compounds as endocrine disruptors, we studied the androgenicity of them wing in vivo and in vitro androgenicity assay system. Administration of 2,4-D (50 mg/kg/day, p.o.) or DCP (100 mg/kg/day, p.o.) to rats caused an increase in the tissue weight of ventral prostate, Cowpers gland and glands penis. These increase of androgen-dependent tissues were additively potentiated when rats were simultaneously treated with low dose of testosterone (1 g/kg, s.c.). 2,4-D increased about 350% of the luciferase activity in the PC cells transiently cotransfected phAR and pMMTV-Luc at concentration of $10^{-9}$ M. In 2,4-D or DCP-treated castrated rats, testosterone 6$\beta$-hydroxylase activity was not significantly modulated even when rats were co-treated with testosterone. In vitro incubation of 2,4-D and DCP with microsomes at 50 $\mu$M inhibited testosterone 6$\beta$-hydroxylase activity about 27% and 66% in rat liver microsomes, about 44% and 54% in human liver microsomes and about 50% and 45% in recombinant CYP3A4 system, respectively. The amounts of total testosterone metabolites were reduced about 33% and 75% in rat liver microsomes, 69% and 73% in human liver microsomes and 54% and 64% in recombinant CYP3A4 by 2,4-D or DCP, respectively. Therefore, the additive androgenic effect of 2,4-D or DCP by the co-administration of the low dose of testosterone may be due to the increased plasma level of testosterone by inhibiting the cytochrome P450-mediated metabolism of testosterone. These results collectively suggested that 2,4-D and DCP may act as androgenic endocrine disrupter by binding to the androgen receptor as well as by inhibiting the metabolism of testosterone.

• 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.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2005년도 춘계 국제심포지엄 및 학술대회
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• pp.184-184
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• 2005

• 한국수산과학회지
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• 제52권1호
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• pp.74-80
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• 2019

Nonylphenol is an endocrine-disrupting chemical that is the degradation product of the nonionic surfactants nonylphenol ethoxylates. To understand the contamination and behavioral characteristics of nonylphenol, we measured the nonylphenol concentrations in surface water in the lower reaches of the Suyeong River, Korea. The results were used to estimate the material balance. The target area was divided into three regions to estimate the material balance of nonylphenol. In region 1, in flux of the dissolved nonylphenol was 282.3 g/day and the nonylphenol influx in particulate suspended solids was 1,582.8 g/day. The dissolved nonylphenol outflow discharged toward region 2 was 192.5 g/day, while the adsorption to particulate suspended solids was 89.8 g/day. Within the particulate suspended solids, the outflow to region 2 was 1,250.0 g/day, while the estimated amount settling in the sediments was 422.7 g/day. The adsorption of dissolved nonylphenol to the particulate suspended solids in regions 1 and 2 was 31.8% and 54.9%, respectively. In region 3, the desorption rate was 8.8%.

• 한국발생생물학회지:발생과생식
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• 제9권2호
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• pp.85-93
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• 2005

스테로이드 호르몬인 에스트로겐은 여러 조직의 발생 및 분화에 영향을 주는 것으로 알려져 있다. 최근 에스트로겐의 영향을 평가하는데 있어 전통적인 여성 호르몬이라는 인식을 탈피하여 수컷 생식계상의 역할에 관한 연구가 활발하게 이루어지고 있다. 특히 내분비계 교란물질에 관한 다양한 연구 결과가 보고되면서, 수컷에서의 에스트로겐 역할에 대한 관심이 증대되고 있는 실정이다. 따라서 에스트로겐의 정확한 역할을 파악하기 위해서 발생 단계에 따른 에스트로겐 수용체의 수컷 생식기관 내 분포를 정리해 보고, 내분비계 교란물질의 노출에 따른 수컷 생식계의 발생 및 분화 이상과 정자형성과정의 장애 등을 알아보고자 하였다. 끝으로 외인성 화학물의 에스트로겐성을 평가하기 위한 지표인자들을 정리하여, 남성 생식기관의 발생, 분화, 기능에 관련된 에스트로겐의 역할에 대한 실제적인 정보를 얻을 수 있을 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권8호
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• pp.1118-1126
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• 2010

Male reproduction is influenced by a number of intrinsic and extrinsic factors, including environmental endocrine disruptors. Testosterone is a well recognized intrinsic regulator for development and function of the male reproductive tract, and thus male fertility. The testis and semen of many mammalians contain an unusually high concentration of estrogen. Testosterone is converted into estrogen by the enzymatic action of cytochrome P450 aromatase complex (Cyp19a1). Of the male reproductive tract, the efferent ductules (EDs) possess exceptionally elevated levels of estrogen receptors (ERs), ER${\alpha}$ and ER${\beta}$, indicating that estrogen, in addition to testosterone, would have a functional role in regulation of male reproduction. First, this review has focused on description and summary of what is currently known for functions of estrogen in the EDs. The biosynthetic pathway of estrogen occurring in the testis is briefly covered, following by detailed explanation of the morphology and physiology of EDs. In the next section, the sources and targets of estrogen in the male reproductive tract are highlighted, and possible functional roles of estrogen in the EDs are justified from the aspect of physiology, molecular biology, and morphology in adult animal models. Also, this section covers the importance of estrogen and ERs in maintaining normal function and morphology of the EDs during postnatal development. In the last part of this review, the effects of extrinsic factors, especially environmental endocrine-disruptors, on the EDs is summarized. The intent of this review is to emphasize the importance of estrogen for regulation of physiological function of the EDs, and thus male fertility.

• 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.

• 생약학회지
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• 제31권4호
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• pp.455-458
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• 2000

Research on pesticide residues as endocrine disruptors in natural medicines was initiated by Korea Food & Drug Administration this year. We determined the presence and levels of certain pesticides in selected natural medicines. The natural medicines collected this year are Glycyrrhiza Root, Cinnamon Bark, Pueraria Root, Polygonatum Rhizome, Jujube, Schizandra Fruit, Lycium Fruit, Liriope Tuber, Eucommia Bark, Peony Root, Korean Angelica, Dioscorea Rhizome, Cnidium Rhizome, Cassia Seed, Platycodon Root, Comus Fruit, Mentha Herb, Epimedium Herb, Bupleurum Root, and Ginger, which have no data for pesticide residues and 192 samples of them were circulated in Korea, 28 samples were circulated in China. In order to analyze many pesticides in large number of samples we used simultaneous multi-residue analysis of pesticides by GC-ECD, which was followed by GC-MSD analysis to confirm the identity of the detected pesticide in each sample.