• Development and Reproduction
• /
• v.11 no.3
• /
• pp.179-185
• /
• 2007

The estrogens and estrogenic endocrine disrupting chemicals(EDCs) function through a steroid nuclear receptor-mediated process and subsequently regulate the transcription of mRNA for a number of target proteins. The estrogen receptor-related receptors(ERRs), which are structurally similar to estrogen receptors, are members of orphan nuclear receptor in the nuclear receptor superfamily and their functions are known to be involved in the formation of extra-embryonic ectoderm. To investigate effects of EDCs on early embryogenesis and ERR gene expression in marine invertebrates, we examined morphological changes and the mRNA expression of $ERR{\beta}$ like 1 in sea urchin Strongylocentrotus nudus exposed to estradiol-$17{\beta}(E_2)$ or nonylphenol(NP). The $E_2$ and NP-exposed embryos showed a delayed development compared to control embryos. Furthermore, they showed abnormal embryonic developments at late stages, i.e., blastular, gastrula and plutei stages. The mRNA level of $ERR{\beta}$ like 1 at the gastrula stage was significantly lower in $E_2$ and NP-exposed embryos than those of control group. These results suggest that NP and $E_2$ are potent chemicals causing abnormal embryonic development of S. nudus through at least in part down-regulated $ERR{\beta}$ like 1.

• The Korean Journal of Pesticide Science
• /
• v.7 no.3
• /
• pp.188-197
• /
• 2003

Endocrine disrupting chemicals (EDCs) can alter hormone regulation that control reproductive system in animals. The effects of endosulfan, molinate, and alachlor that suspected to have examined disruption EDCs effect on a fish species of interest, Xiphophorus helleri (swordtail fish), were studied using vitellogenin (Vtg) and aromatase as diagnostic biomarkers. Induction of Vtg proteins was detected by RT-PCR in male fish treated with alachlor, and mixture of endosulfan and molinate in dose response manner. Also, induction of aromatase was detected by RT-PCR in male fish treated with alachlor, endosulfan, and mixture of endosulfan and molinate in sinlilar manner. In this study, swordtail fish exposed to endosulfan or molinate individually did not show any adverse effects. However, Vtg and aromatase expressions and apoptosis were detected in swordtail. fish exposed to the mixture of endosulfan and molinate. These results suggested that low concentrations of mixture of molinate and endosulfan individually do not affect swordtail fish, but may influence genital system, and induce apoptosis.

• Toxicological Research
• /
• v.27 no.4
• /
• pp.253-259
• /
• 2011

Transforming growth factor ${\beta}$ (TGF-${\beta}$) is involved in cellular processes including growth, differentiation, apoptosis, migration, and homeostasis. Generally, TGF-${\beta}$ is the inhibitor of cell cycle progression and plays a role in enhancing the antagonistic effects of many growth factors. Unlike the antiproliferative effect of TGF-${\beta}$, E2, an endogeneous estrogen, is stimulating cell proliferation in the estrogen-dependent organs, which are mediated via the estrogen receptors, $ER{\alpha}$ and $ER{\beta}$, and may be considered as a critical risk factor in tumorigenesis of hormone-responsive cancers. Previous researches reported the cross-talk between estrogen/$ER{\alpha}$ and TGF-${\beta}$ pathway. Especially, based on the E2-mediated inhibition of TGF-${\beta}$ signaling, we examined the inhibition effect of 4-tert-octylphenol (OP) and 4-nonylphenol (NP), which are well known xenoestrogens in endocrine disrupting chemicals (EDCs), on TGF-${\beta}$ signaling via semi-quantitative reverse-transcription PCR. The treatment of E2, OP, or NP resulted in the downregulation of TGF-${\beta}$ receptor2 (TGF-${\beta}$ R2) in TGF-${\beta}$ signaling pathway. However, the expression level of TGF-${\beta}1$ and TGF-${\beta}$ receptor1 (TGF-${\beta}$ R1) genes was not altered. On the other hand, E2, OP, or NP upregulated the expression of a cell-cycle regulating gene, c-myc, which is a oncogene and a downstream target gene of TGF-${\beta}$ signaling pathway. As a result of downregulation of TGF-${\beta}$ R2 and the upregulation of c-myc, E2, OP, or NP increased cell proliferation of BG-1 ovarian cancer cells. Taken together, these results suggest that E2 and these two EDCs may mediate cancer cell proliferation by inhibiting TGF-${\beta}$ signaling via the downregulation of TGF-${\beta}$ R2 and the upregulation of c-myc oncogene. In addition, it can be inferred that these EDCs have the possibility of tumorigenesis in estrogen-responsive organs by certainly representing estrogenic effect in inhibiting TGF-${\beta}$ signaling.

• Journal of Korean Society of Water and Wastewater
• /
• v.32 no.6
• /
• pp.499-505
• /
• 2018

We applied column experiments to investigate the environmental fate and transport of silver nanoparticles(AgNPs) in fully saturated conditions of porous media. These column experiments were performed to emphasize oxidation method with $H_2O_2$ concentration and acidic conditions. The mobility of AgNPs was decreased with the increasing ionic strength that the surface charge of AgNPs(zeta potential) was neutralized with the presence of positive ions of $Na^+$. Additionally, it was also affected due to that not only more increased aggregated size of AgNPs and surface charge of quartz sand. The decreased breakthrough curves(BTCs) of bisphenol-A(BPA) and $17{\alpha}$-ethynylestradiol(EE2) were removed approximately 35.3 and 40%. This is due to that endocrine disrupting chemicals(EDCs) were removed with the release of $OH{\cdot}$ radicals by the fenton-like mechanisms from acidic and fenton-like reagent presenting. This results considered that higher input AgNPs with acidic conditions is proved to realistic in-situ oxidation method. Overall, it should be emphasized that a set of column experiments employed with adjusting pH and $H_2O_2$ concentration in proved to be effective method having potential ability of in-situ degradation for removing organic contaminants such as BPA and EE2.

• Molecules and Cells
• /
• v.41 no.12
• /
• pp.1052-1060
• /
• 2018

Triclosan (TCS) is a phenolic antimicrobial chemical used in consumer products and medical devices. Evidence from in vitro and in vivo animal studies has linked TCS to numerous health problems, including allergic, cardiovascular, and neurodegenerative disease. Using Caenorhabditis elegans as a model system, we here show that short-term TCS treatment ($LC_{50}$: ~0.2 mM) significantly induced mortality in a dose-dependent manner. Notably, TCS-induced mortality was dramatically suppressed by co-treatment with non-ionic surfactants (NISs: e.g., Tween 20, Tween 80, NP-40, and Triton X-100), but not with anionic surfactants (e.g., sodium dodecyl sulfate). To identify the range of compounds susceptible to NIS inhibition, other structurally related chemical compounds were also examined. Of the compounds tested, only the toxicity of phenolic compounds (bisphenol A and benzyl 4-hydroxybenzoic acid) was significantly abrogated by NISs. Mechanistic analyses using TCS revealed that NISs appear to interfere with TCS-mediated mortality by micellar solubilization. Once internalized, the TCS-micelle complex is inefficiently exported in worms lacking PMP-3 (encoding an ATP-binding cassette (ABC) transporter) transmembrane protein, resulting in overt toxicity. Since many EDCs and surfactants are extensively used in commercial products, findings from this study provide valuable insights to devise safer pharmaceutical and nutritional preparations.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.12
• /
• pp.4809-4813
• /
• 2014

Endocrine-disrupting chemicals (EDCs) have been reported to interfere with estrogen signaling. Exposure to these chemicals decreases the immune response and causes a wide range of diseases in animals and humans. Recently, many studies showed that licorice (Glycyrrhiza glabra) root extract (LRE) commonly called "gamcho" in Korea exhibits antioxidative, chemoprotective, and detoxifying properties. This study aimed to investigate the mechanism of action of LRE and to determine if and how LRE can alleviate the toxicity of EDCs. LRE was prepared by vacuum evaporation and freeze-drying after homogenization of licorice root powder that was soaked in 80% ethanol for 72 h. We used 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as a representative EDC, which is known to induce tumors or cancers; MCF-7 breast cancer cells, used as a tumor model, were treated with TCDD and various concentrations of LRE (0, 50, 100, 200, $400{\mu}g/mL$) for 24, 48, and 72 h. As a result, TCDD stimulated MCF-7 cell proliferation, but LRE significantly inhibited TCDD-induced MCF-7 cell proliferation in a dose- and time-dependent manner. The expression of TCDD toxicity-related genes, i.e., aryl hydrocarbon receptor (AhR), AhR nuclear translocator, and cytochrome P450 1A1, was also down-regulated by LRE in a dose-dependent manner. Analysis of cell cycle distribution after treatment of MCF-7 cells with TCDD showed that LRE inhibited the proliferation of MCF-7 cells via G2/M phase arrest. Reverse transcription-polymerase chain reaction and Western blot analysis also revealed that LRE dose-dependently increased the expression of the tumor suppressor genes p53 and p27 and down-regulated the expression of cell cycle-related genes. These data suggest that LRE can mitigate the tumorigenic effects of TCDD in breast cancer cells by suppression of AhR expression and cell cycle arrest. Thus, LRE can be used as a potential toxicity-alleviating agent against EDC-mediated diseases.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.13
• /
• pp.5117-5121
• /
• 2014

Endocrine-disrupting chemicals (EDCs) have been reported to interfere with estrogen signaling. Exposure to these chemicals decreases the immune response and causes a wide range of diseases in animals and humans. Recently, many studies showed that licorice (Glycyrrhiza glabra) root extract (LRE) commonly called "gamcho" in Korea exhibits antioxidative, chemoprotective, and detoxifying properties. This study aimed to investigate the mechanism of action of LRE and to determine if and how LRE can alleviate the toxicity of EDCs. LRE was prepared by vacuum evaporation and freeze-drying after homogenization of licorice root powder that was soaked in 80% ethanol for 72 h. We used 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as an EDC, which is known to induce tumors or cancers; MCF-7 breast cancer cells were used as a tumorigenic model. These were treated with TCDD and various concentrations of LRE (0, 50, 100, 200, $400{\mu}g/mL$) for 24, 48, and 72 h. As a result, TCDD stimulated MCF-7 cell proliferation, but LRE significantly inhibited TCDD-induced MCF-7 cell proliferation in a dose- and time-dependent manner. Expression of TCDD toxicity-related genes, i.e., aryl hydrocarbon receptor (AhR), AhR nuclear translocator, and cytochrome P450 1A1, were subsequently down-regulated by LRE in a dose-dependent manner. Analysis of cell cycle distribution after treatment of MCF-7 cells with TCDD and various concentrations of LRE showed that LRE inhibited the proliferation of MCF-7 cells via G2/M phase arrest. Reverse transcription-polymerase chain reaction and Western blot analyses also revealed that LRE dose-dependently increased the expression of the tumor suppressor genes p53 and p27 and down-regulated the expression of cell cycle-related genes. These data suggest that LRE can mitigate the tumorigenic effects of TCDD in breast cancer cells by suppression of AhR expression and cell cycle arrest. Thus, LRE can be used as a potential toxicity-alleviating agent against EDC-mediated disease.

• Proceedings of the Korean Society of Toxicology Conference
• /
• 2006.11a
• /
• pp.34-45
• /
• 2006

Chemical toxicants are metabolically converted to numerous metabolites in the body. Toxicokinetic characteristics of metabolites could be therefore used as biomarker of exposure for human risk assessment. Biologically based dose response (BBDR) model was proposed for future direction of risk assessment. However, this area has not been developed well enough for human application. Benzo(a)pyrene (BP), for example, is a well-known environmental carcinogen and may produce more than 100 metabolites and BPDE-DNA adduct, a covalently bound form of DNA with benzo(a)pyrene diolepoxides (BPDES), has been applied to qualitatively or quantitaively estimate human exposure to BP. In addition, di(2-ethylhexyl) phthalate (DEHP), a widely used plasticize. in the polymer industry, is one of endocrine-disrupting chemicals (EDCs) and has been monitored in humans using urinary or serum concentrations of DEHP or its monomer MEHP for exposure and risk assessment. However, it is difficult to estimate the actual level of toxicants using these biomarkers in humans using. This presentation will discuss a methodology of exposure and risk assessment by application of metabolic profiling kinetics.

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2001.05a
• /
• pp.473-474
• /
• 2001

스테로이드 호르몬과 유사한 기능을 하는 유기 화합물질들의 존재가 밝혀지고 있고, 이러 한 물질을 내분비 장애물질 (endocrine disrupting chemicals, EDCs)이라 명명하고 있다 (Kavlock et al., 1996). PCBs는 자연에서 쉽게 분해되지 않는 난분해성 물질이지만 생물체의 지방성분에는 쉽게 용해되는 지용성이다. 이 물질은 화학구조가 생명체의 호르몬과 비슷해 생명체에 흡수될 경우 정상적인 호르몬의 기능을 혼란시켜 생식기의 기형, 생식기능의 저하, 행동의 변화 등을 유발하는 것으로 알려지고 있다(Colborn et al., 1996). (중략)

• Animal cells and systems
• /
• v.13 no.3
• /
• pp.339-344
• /
• 2009

This study aims to find out the effect of heavy metals, as is the case of EDCs (endocrine disrupting chemicals), on reproductive endocrine disruption of aquatic animals. In the present experiment zinc, which is a heavy metal well known for its androgenous activity, was used. The experimental period was 24 weeks, starting in November during the inactive stage of the clam's reproductive cycle. The experimental groups were composed of one control condition and three zinc exposure conditions (0.64, 1.07, and 1.79 mg/L). The sex ratio (F:M) was 1:1.06 in the control group and 1:1.70 in all the exposed group, illustrating the tendency for higher proportion of males with increases in zinc concentration. Gonad maturity was higher in 1.07, and 1.79 mg/L groups compared to the control group, with higher maturity observed in males than females. Intersex individuals made up 24.7% of the exposed group, while females exhibited a higher ratio than the males with increasing zinc concentration. The results of this study indicate that zinc functions as an androgenic effector on the reproduction of Gomphina veneriformis.