• Biomedical Science Letters
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• v.10 no.4
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• pp.403-406
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• 2004

Environmental endocrine disruptors (EDs) are toxic, hormone-like chemicals which can be found in our normal daily life. We have examined if EDs can inhibit the monocellular microorganisms such as lactic acid bacteria or if the growth of lactic acid bacteria could be resistant to the endocrine disruptors. We have used Lactobacillus paracasei subsp. paracasei (KCTC No. 3165) as an experimental strain and bisphenol A, benzophenone and phenylphenol for the comparison purpose. Experiments included the evaluation of turbidity, absorbance and actual cell counts. We found that No.3165 was somewhat resistant to EDs naturally, however, high concentration of EDs could inhibit the growth of No. 3165 completely. Different EDs showed different spectrum of inhibit. This study should contribute to the development of more resistant lactic acid bacteria to EDs and to the development of functional fermented beverage.

• Korean Journal of Environmental Biology
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• v.33 no.4
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• pp.361-374
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• 2015

Endocirne disruptors (EDs) can cause fertility decrease, developmental disorder, and even cancer in animals. Until 90's, EDs were used in various synthetic products including paints, coatings, detergents, plastics, and plasticizers. Currently, in several countries, the production, trade and use of EDs or EDs-suspected chemicals have been regulated while activity to screen the alternatives for EDs including bisphenol-A, phthalate and nonylphenol is active. Although various toxicity test method was developed and applied for screening of alternatives, however, the safety of alternatives has been not fully demonstrated. Some alternatives have high structural similarity with existing EDs, raising the possible risk of endocrine disruption by alternatives. In an effort to develop the safe alternatives, we reviewed the effects of EDs such as bisphenol-A, phthalates, nonylphenol and their substituents. In addition, in-silico analysis for endocrine disrupting activities of some alternatives was presented.

• Journal of Embryo Transfer
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• v.22 no.4
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• pp.199-208
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• 2007

Although many studies have focused on the biological and toxicological effects of phenol products, in particular, in reproductive tracts, the data about their effects in this estrogenic responsive tissue are much less clear. In addition, the in vitro and in vivo data concerning ED-adverse impacts in other endocrine organs, i.e. pituitary gland, are not understood well either. Thus, a further study is needed for providing a new insight into possible impacts of estrogenic EDs including phenol products in humans and wildlife. A combination of in vitro and in vivo system for examining EDs may bring better understanding into the regulatory mechanisms underlying EDs-induced events. In addition, this information may support for developing optimal screening methods of estrogenic EDs, in particular, phenol products.

• Journal of Environmental Health Sciences
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• v.31 no.5 s.86
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• pp.431-443
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• 2005

This study was performed to investigate the perceptions of the opinion leaders, such as government officials, researchers, NGO workers, and journalists on the risks of endocrine disrupters (EDs) and genetically modified organisms (GMOs) as well as the related policies on these two hazards or potential hazards. The opinion leaders generally considered the EDs as the most serious hazard among twenty-one environmental health hazards in Korea, and agreed that the EDs would continuously be the most serious hazard. On overall average, the GMOs were ranked the 11th among the twenty-one health hazards. Further investigation indicated that the GMOs were variously ranked by the group of respondents: they were ranked the 2nd by the NGO workers, the 7th by the journalists, the 9th by the researchers and the 11th by the government officials. In general, the respondents considered the dioxin as a hazard with the highest risk while the GMOs were considered less hazardous. The opinion leaders considered that although the risks of the GMOs and EDs were not fully verified, the risks should be controlled through the legislation. The EDs and GMOs should be separately regulated for the time being, while the EDs should put under more strengthened regulation. It is recommended that a web-site containing the information on the EDs and the GMOs be prepared for the journalists. In addition, a training program in relation to the EDs and the GMOs needs to be organized by the Korean Press Foundation and the Korea Food and Drug Administration to educate the journalists. A committee consisting of government officials, scientists, and NGO workers needs to be established, and it should provide framework of future policies and public relations programs.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.8
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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.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.117-120
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• 2000

For detecting toxicity of endocrine disruptors (EDs), rapid, sensitive, and simple methods are needed. Therefore, in this study, a new method in which the different toxic effect of EDs can be monitored using 4 different recombinant bacteria was designed and evaluated. It was found that the recombinant bacteria could monitor the toxic effect, not estrogenic effect, due to EDCs through the measurement of bioluminescence and cell growth rate, which were shown to depend upon a form of cellular toxicity, such as DNA damage, protein damage, oxidative damage, and membrane damage. In addition, it was found that the damage done by EDCs can be divided into several groups based upon the toxic mechanisms of the EDCs

• Journal of Embryo Transfer
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• v.23 no.4
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• pp.229-237
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• 2008

Recently, parabens have been believed to act as xenoestrogens, an identified class of endocrine disruptors (EDs). These environmental compounds are the most well-known as preservatives in many commercial products, including food, cosmetics and pharmaceutical industries. It has been demonstrated that the human health risks of parabens result from a long-term exposure to skin in which this chemical group is rapidly absorbed through the skin. On the other hand, parabens are also completely absorbed from gastrointestinal tract. It has reported that these substances possess several biological effects in which inhibitory property involved in membrane transports and mitochondrial functions is considered to be important for their action. Testing of parabens has revealed that estrogen-like activities of these chemicals are much less potent than natural estrogen, $17{\beta}$ estradiol (E2). Additionally, the estrogenicity of individual paraben- compounds is distinct depending upon their biochemical structure. Recent findings of paraben-estrogenic activities have shown that these compounds may affect breast cancer incidence in women, suggesting adverse ecological outcomes of this environmental group on human and animal health. Although the biological and toxicological effects of parabens have been demonstrated in many previous studies, possible mechanism(s) of their action are required to be explored in order to bring the better understanding in the detrimental impacts of parabens in human and wildlife. There have several different types of parabens which are the most widely used as preservatives. These include methyl-paraben, ethylparaben, propylparaben, butylparaben and p-hydroxybenzoic acid, a major metabolite of parabens. In this review, we summarize current database based on in vitro and in vivo assays for estrogenic activities and health risk assessment of paraben- EDs which have been published previously.

• Environmental Mutagens and Carcinogens
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• v.22 no.3
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• pp.175-182
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• 2002

Endocrine disruptors (EDs) are the chemicals that affect endocrine systems through activation or inhibition of steroid hormone response. It is necessary to have a good system to evaluate rapidly and accurately endocrine-disrupting activities of suspected chemicals and their degradation products. The key targets of EDs are nuclear hormone receptors, which bind to steroid hormones and regulate their gene transcription. We constructed a co-expression system of Gal4p DNA binding domain (DBD)- ligand binding domain of human estrogen receptor $\alpha$ or $\beta$, and Gal4p transactivation domain (TAD)-co-activator AIB-1, SRC-1 or TIF-2 in Saccharomyces cerevisiae with a chromosome-integrated lacZ reporter gene under the control of CYC1 promoter and Gal4p binding site (GAL4 upstream activating sequence, GAL4$_{UAS}$). Expression of this reporter gene was dependent on the presence of estrogen or EDs in the culture medium. We found that the two-hybrid system with combination of the hER$\beta$ LBD and co-activator SRC-1 was most effective in the xenoestrogen-dependent induction of reporter activity. The extent of transcriptional activation by those chemicals correlated with their estrogenic activities measured by other assay systems, indicating that this assay system is efficient and reliable for measuring estrogenic activity. The data in this research demonstrated that the yeast detection system using steroid hormone receptor and co-activator is a useful tool for identifying chemicals that interact with steroid receptors.s.

• Toxicological Research
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• v.22 no.4
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• pp.307-313
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• 2006

The development of in vitro assays has been recommended to screening and testing the potential endocrine disruptors (EDs). These assay systems focus only on identifying the estrogenic or antiestrogenic activity of EDs, whereas a few studies have been carried out to screen the thyroid hormone (TH) disruptors. The aim of this study was to evaluate a test system to detect TH disruptors using rat pituitary tumor $GH_3$ cells. The test system is based on the TH-dependent increase in growth rate. As expected, L-3,5,3-triiodothyronine ($(T_3)$ markedly induced a morphological change in $GH_3$ cells from flattened fibroblastic types to rounded or spindle-shaped types. $T_3$ stimulated $GH_3$ cell growth in a dose-dependent manner with the maximum growth-stimulating effect being observed at a concentration $1{\times}10^9M$. In addition, $T_3$ increased the release of growth hormone and prolactin into the medium of the $GH_3$ cells culture. Using this assay system, the TH-disrupting activities of bisphenol A (BPA) and its related compounds were examined. BPA, dimethy/bisphenol A (DMBPA), and TCI-EP significantly enhanced the growth of $GH_3$ cells in the range of $1{\times}10^{-5}M\;to\;1{\times}10^{-6}M$ concentrations. In conclusion, this in vitro assay system might be useful for identifying potential TH disruptors. However, this method will require further evaluation and standardization before it can be used as a broad-based screening tool.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.11a
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• pp.169-169
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• 2002