• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2002.10a
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• pp.170-170
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• 2002

College of Pharmacy, Ewha womans University, Seoul, 120-750, Korea 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the most potent halogenated aromatic hydrocarbon congener that induces expression of several genes including CYP1A1. Exposure to TCDD results in many toxic actions such as carcinogenesis, hepatotoxicity, immune suppression, and reproductive and developmental toxicity. Dramatic differences in dioxin toxicity have been observed between the sexes of some animal species, suggesting hormonal modulation of dioxin action. Many studies have been reported and propose several mechanisms of anti-estrogenic effects of TCDD. In contrast, the effect of estrogen on the regulation of CYP1A1 are not clear at present. There are several reports showing conflicting results. It seems that induction/inhibition of CYP1A1 may be dependent on cell-type and concentration. The purpose of this study was to investigate the regulation of TCDD-induced CYP1A1 gene expression by estradiol and its metabolites. We examined whether estradiol and its metabolites altered TCDD-mediated induction of CYP1A1 enzyme activity. 17 ${\beta}$ estradiol and 16 ${\alpha}$ estriol at non cytotoxic concentrations caused a significant concentration dependent decline of TCDD-induced EROD activity To determine whether reduced EROD activity reflected altered CYP1A1 mRNA expression, we measured CYP1A1 mRNA level by RT-PCR. And to examine whether estradiol and its metabolites have effects on TCDD-induced CYP1A1 gene expression at the transcription level, we also peformed transient transfection with an AhR responsive reporter plasmid containing the 5' flanking region of the human CYP1A1 gene to examine whether estradiol and its metabolites have effects on TCDD-induced CYP1A1 gene expression at the transcription level.

• Development and Reproduction
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• v.23 no.4
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• pp.333-344
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• 2019

In vertebrate reproductive system, estrogen receptor (ER) plays a pivotal role in mediation of estrogenic signaling pathways. In the present study, we report the cDNA cloning, expression analysis, and transcriptional activity of ERβ1 subtype from medaka Oryzias dancena. The deduced O. dancena ERβ1 (odERβ1; 519 amino acids) contained six characteristic A/B to E/F domains with very short activation function 2 region (called AF2). A phylogenetic analysis indicated that odERβ1 was highly conserved among teleost ERβ1 subgroup. A conventional RT-PCR revealed that the odERβ1 transcripts were widely distributed in the multiple tissues, the ovary, brain, gill, intestine, kidney, and muscle. Further, the relatively higher odERβ1 expressions in the ovary and brain were clearly reproduced in RT-qPCR assay. When HA-fused odERβ1 expression vector was transfected into HEK293 cells, an immunoreactivity for odERβ1 was mainly detected in the nucleus part. Finally, an estrogen responsive element driven luciferase reporter assays demonstrated that the transcriptional activity of odERβ1 significantly increased by estradiol-17β (E2) in a dose dependent manner (p<0.05). However, fold-activation of odERβ1 in the presence of E2 was markedly weak, when it compared with those of O. latipes ERβ1. Taken together, these data suggest that odERβ1 represents a functional variant of teleost ERβ subtype and provides a basic tool allowing future studies examining the function of F domain of ERβ1 subtype and expanding our knowledge of ERβ evolution.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.220-227
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• 2010

Puerariae radix (PR) is a popular natural herb and a traditional food in Asia, which has antithrombotic and anti-allergic properties and stimulates estrogenic activity. One of the major side effects of cisplatin is nephrotoxicity, leading to acute renal failure. Recent study has suggested a role of ROS and p53 in renal cell injury by cisplatin. We studied that protective effects of PR on cisplatin-induced apoptosis in rat mesangial cell. Rat mesangial cell was preincubated with PR (50, 100, 150 and 200 ${\mu}g/m{\ell}$) for 12 hr and then treated with 30 ${\mu}M$ cisplatin for 24 hr. Protective effect of PR on cisplatin-induced apoptosis in ECV304 cells was determined using MTT assay, FDA-PI staining, flow cytometric analysis, caspase-3 activity assay, ROS assay and western blot. Our results showed that PR inhibited in cisplatin-induced apoptosis and ROS production in ECV304 cells. Moreover, PR reduced ERK, p38 and JNK activation that increased in cisplatin-treated rat mesangial cell. Furthermore, activation of p53 by cisplatin in rat mesangial cell was inhibited by PR treatment. These results suggest that protective effect of PR on cisplatin-induced apoptosis in rat mesangial cell may be associated with reduction of ERK, p38, JNK, p53 activation.

• Journal of Food Hygiene and Safety
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• v.25 no.1
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• pp.79-82
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• 2010

The pomegranate (Punica granatum), especially its fruit, possesses a vast ethnomedical history and represents a phytochemical reservoir of heuristic medical value. The tree and fruit can be divided into several anatomical compartments, and the fruit juice, peel and oil are known to be weakly estrogenic and heuristically of interest for treatment of menopausal symptoms and sequellae. In this study, analysis of estrogen in pomegranate extract was carried out with LC/MS/MS. Three batches of pomegranate extract samples were used to analysis the target compounds (estrogen). The contents of estrogen derivatives in the samples were 38.6 ppb of estriol, 83.5 ppb of estrone, and 10.9 ppb of estradiol. This result suggests that the pomegranate extract can used for treatment of menopause symptoms in the woman.

• Molecules and Cells
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• v.26 no.1
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• pp.74-80
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• 2008

Bisphenol A bis (2,3-dihydroxypropyl) ether ($BADGE.2H_2O$) is a component of commercial liquid epoxy resins commonly used in the food-packing industry and in dental sealants. There is evidence that it has significant estrogenic activity. Nur77 plays a crucial role in the regulation of certain genes involved in LH-mediated steroidogenesis in testicular Leydig cells. It was previously demonstrated that Bisphenol A (BPA) stimulates Nur77 gene induction and steroidogenesis. In this study, we investigated the effects of $BADGE.2H_2O$ on Nur77 gene expression and steroidogenesis. Northern blot analysis showed that it increased the expression of Nur77 mRNA and protein, and transient transfection assays demonstrated that it increased the promoter activity and transactivation of Nur77. It also increased the expression of certain steroidogenic genes, such as StAR and $3{\beta}$-HSD. Finally, over-expression of a dominant negative Nur77 cDNA via adenoviral infection reduced $BADGE.2H_2O$-mediated progesterone biosynthesis. These results indicate that $BADGE.2H_2O$ disrupts testicular steroidogenesis by increasing Nur77 gene expression.

• Journal of Environmental Health Sciences
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• v.30 no.2
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• pp.71-78
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• 2004

This study was performed to evaluate developmental and estrogenic activity of bisphenol A (BPA) and butyl benzyl phthalate (BBP) to the second generation of Sprague-Dawley rats ingested during gestational or lactational periods. Rats were given BPA 20$\mu\textrm{g}$/kg BBP 100mg/kg of pregnancy or lactation periods. Maternal body weight and neonatal body weight were recorded. The rats were sacrificed on day 21 after birth. Reproductive organs of dam and neonate were utilized for receptor binding assay. The plasma concentrations of BPA and MBep, one of the major metabolites of BBP were analyzed with HPLC. The co-administration of BPA and BBP induced slow weight gain compared with single administration in dams. Also, such mixture induced low neonatal body weights in next generation. The dams treated with BPA and BBP during lactational periods showed significant organ weight changes in liver and spleen. The dams exposed during lactational periods showed significant organ weight changes not only in liver and spleen but also in kidney, uterus and ovary. The F1 female rats exposed during lactation periods showed significant organ weight changes in liver, spleen, ovary. The F1 male rats showed significant organ weight changes in liver, kidney, epididymis, vesicular glands, prostate. However, no clear synergistic effects of BPA and BBP were noted. There was no significantly different ER$\alpha$ expression pattern between control and treated groups. However, ER$\alpha$ expression were increased in F1 male testis and female uterus. PI male showed distinct ER$\alpha$ expression, especially in the group of lactational combined exposure. Synergistic ER$\alpha$ expression was found by combined treatment of BPA and BBP. We could not find any evidences of synergistic effects on BPA and/or BBP combined administration on dams and their fetuses, except in ER$\alpha$ expression of F1 male.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.254-258
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• 2006

Vitellogenin has been known as a potent biomarker protein for the estrogenic activity in fish exposed to endocrine disruptors. In this study, a piezoelectric immunosensor making use of an anticarp vitellogenin antibody and an AT-cut quartz crystal microbalance as the biological component and transducer was prepared, followed by its application to the analysis of carp vitellogenin as follows. Antibody immobilization was conducted by chemisorption of a thiolated antibody with a heterobifunctional thiolation cross-linker, sulfosuccinimidyl 6-[3-(2-pyridyldithio)propionamido]hexanoate. The reaction buffer for the immunosensor system was optimized as 0.1 M sodium phosphate (pH 7.4). Concentration-dependent sensor responses were obtained in the vitellogenin concentrations ranging from 0.4864 to 486.4000 nM, with a linear correlation between vitellogenin concentration and frequency shift in double-logarithmic scale. The limit of detection of the immunosensor for carp vitellogenin was presumed as 0.4864 nM.

• KSBB Journal
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• v.16 no.2
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• pp.174-178
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• 2001

Soybeans contain the phytoestrogens genistein and daidzein, their glucosides genistin and daidzin and coumesterol. These isoflavonoid compounds are capable of producing an estrogenic response in a number of diverse species. This study determined optimum conditions for the extraction of the main isoflavones(daidzin, genistin, daidzein, genistein) in defatted soybean meal using high-performance liquid chromatography. The best optimum extraction was achieved at 75% ethanol, $80^{circ}C$, pH4 and a three hour contact time. In addition, isoflavones with high purity were separated by adding up to 4%(w/v) of calcium chloride dihydrate. Most soybean extracts were composed of $beta$-glucosidic conjugate(daidzin, genistin) which is difficult to adsorb in body. Therefore, $beta$-glucosidase was used to convert as conjugate to aglycone form (daidzein, genistein) which is easy to adsorb. The optimal conditions of enzyme reaction involved to be 8.4 units of enzyme concentration, pH5.0, $40^{circ}C$ and 40 minutes.

• Journal of Food Hygiene and Safety
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• v.21 no.4
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• pp.258-262
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• 2006

To investigate additive effects of endocrine disruptors, we have histopathologically studied the exchanges of the reproductive organ to ovariectomized ICR mice. Female ICR mice were ovariectomized and then treated with endocrine disruptors after two weeks. Macroscopic exchanges, which were body weight, feed and water intake, of all groups were not seen during experiment period. Histopathological changes of uterine epithelial cells, vaginal epithelial cells, mammary glands and the diameter in uterine tubles were observed. In the results, the histopathological sensitivity to endocrine disruptors effect was more seen to the vaginal epithelial cell height than others. The additive estrogenic effects of endocrine disruptors, which were combinations of DEHP, DBP and BPA, were seen with E2 and BPA treatments. These results offers a sysmatic and mechanistically informative approach to assessing estrogenicity. It provides a useful profile of activity using a reasonable amount of resources and is compatible with the study of individual chemicals as well as the investigation of interactions among combinations of chemicals.

• Clinical and Experimental Reproductive Medicine
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• v.45 no.4
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• pp.163-169
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• 2018

Objective: Zearalenone (ZEA) is a mycotoxin with potent estrogenic effects. Saffron is an herbal product that has antioxidant activities. The objective of this study was to investigate the protective role of saffron against reproductive toxicity induced by ZEA in female mice. Methods: Ninety 8-week-old female mice were randomly allocated into three treatment groups. The first group received an intraperitoneal injection of ZEA (2.5 mg/kg) on alternate days. The second group received ZEA (2.5 mg/kg) on alternate days plus oral saffron daily (50 mg/kg). The third group was treated with a vehicle of 1% dimethyl sulfoxide (DMSO) on alternate days, as a control. Ten mice were euthanized from each group at 30, 60, and 90 days of treatment. Serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol ($E_2$), and progesterone (P) were assessed. The uterus and ovaries were examined for changes in size or morphology. Results: Serum levels of LH, FSH, $E_2$, and P in the female mice treated with ZEA plus saffron were significantly higher than in those treated with ZEA alone, and were not significantly different from those treated with 1% DMSO. The female mice treated with ZEA alone showed a reduction in size of the uterus and abnormal architecture of the ovaries. Conclusion: The administration of saffron to female mice resulted in a significant reduction in ZEA-induced alterations in reproductive hormone levels, the size of the uterus, and the morphology of the ovaries.