• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.166-166
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• 2002

In the present study, estrogenic or antiestrogenic activity of cypermethrin, a pyrethroid insecticide was investigated. We used immature rat uterotrophic assay, estrogen-responsive calbindin-D9k (CaBP-9k) gene expression assay and luciferase reporter gene assay for measure of estrogenic potential of cypermethrin.(omitted)

• Toxicological Research
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• v.16 no.3
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• pp.201-209
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• 2000

In association with the international validation program to establish a rodent uterotrophic assay, we conducted preliminary uterotrophic assay proposed by GECD using immature female rats. In the present study, oral and subcutaneous routes were chosen to compare the effects of estrogenic com-pounds in the two dosing regimens. The reference compound ethinyl estradiol (EE) and the antagonist ZM189154(ZM) were administered by gavage or subcutaneously (s.c.) to immature female SD rats from 20 to 22 days of age. For each study, sixty-six female rats were randomly assigned to eleven groups: Untreated control, EE 0,0.01, 0.03, 0.1, 0.3, 1.0,3.0 and 10.0 $\mu\textrm{g}$/kg, EE 3.0 $\mu\textrm{g}$/kg(gavage)/0.3 $\mu\textrm{g}$/kg(s.c) & ZM 0.1 mg/kg, and EE 3.0 $\mu\textrm{g}$/kg(gavage)/0.3 $\mu\textrm{g}$/kg (s.c) & ZM 1.0 mg/kg. There were no treatment-related changes in clinical signs, body weights, food consumption, and necropsy findings in any groups of two studies. The wet and blotted uterus weights increased dose-dependently. Histopathological examination revealed that diameter of uterine duct, height of uterine luminal epithelium. and height oj vaginal epithelium increased dose-dependently. The proliferating cell nuclear antigen (PCNA) immunoreactive cells were increased in number dose-dependently. The estrogenic effects observed in the present studies occurred at $\geq$ 0.3 $\mu\textrm{g}$/kg of oral dose and $\geq$ 0.1 $\mu\textrm{g}$/kg of s.c. dose. An antagonistic effect of ZM against EE was found in both uterus weight and histopathological parameters. From the results obtained, it can be concluded that dose-dependence of the uterotrophic assay using EE and ZM was well demonstrated by gavage and subcutaneous administration and that the estrogenic effects of EE by s.c. dose were higher than those by gavage administration. In addition, blotted uterus weight was more sensitive than wet uterus weight and vaginal epithelial height was found to be the most sensitive parameter among the parameters examined.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.769-775
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• 2005

In this study we isolate substances to serve as dietary resources in order to replace the female hormone. Silkworm (Bombyx mori) is one of the most attractive hosts for large-scale production of eukaryotic proteins which have been proven safe as a dietary resource. We report on the estrogenicity of a mixture of silkworm pupa and herbs (Ginseng,Ulkeum, and Hasuo) using the immature rat uterotrophic assay in vivo. Silkworm pupa aqueousextract (KW) and silkworm oil extract (KO) induced effects on the immature rat uterotrophic assay. KO showed neither positive uterotrophic response nor inhibition on E2 induced effect, while KW and MK (mixture of KW and herbs) showed both of the effects. It is concluded that ethanol extracts from silkworm might be a good, therapeutic, natural product for hormone-deficient diseases.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.10a
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• pp.149-149
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• 2003

• Proceedings of the Korean Society of Toxicology Conference
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• 2005.05a
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• pp.107-107
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• 2005

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.149-149
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• 2003

It is well known that many pesticides possess hormonal activity, and thus have been classified as endocrine disruptors. Currently, pyrethroid insecticides are in worldwide use to control in door pests, providing potential for environmental exposure. A few studies of hormonal activities of these pyrethroid insecticides, however, have been reported, and are controversial between studies.(omitted)

• Toxicological Research
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• v.21 no.1
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• pp.31-37
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• 2005

The inhibitory activity against bisphenol-A (BPA), one of well-known endocrine disrupters was examined with the water extracts prepared from the Stem Bark of Syringa velutina (SBS). In this study, we have investigated the effect of SBS on the toxicity caused by BPA in human breast cancer cell line, MCF-7 cells and immature Sprague-Dawley rats. In the estrogen receptor-mediated proliferation assay using MCF-7 cells, BPA (16 ng/ml) induced the cell proliferation, but the water extract of SBS inhibited BPA-induced cell proliferation in a dose-dependent manner. These results are associated with PARP degradation and specific cleavage of anti-apoptotic protein Bcl-2 of apoptotic regulatory factors. Additionally, the BPA (400 mg/100 g) significantly induced the increase of the uterine and virginal weights, while SBS (50 mg/100 g) showed the inhibitory action against BPA, i.e. caused the increase of estrogen-related organ weights in immature rat uterotrophic assay. Taken together, the present data suggest that SBS may have anti-toxicity activities against BPA in vitro and in vivo systems. SBS may be capable of inhibiting adverse effects of BPA such as reproductive disorder.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.11a
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• pp.166-166
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• 2002

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.10a
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• pp.57-69
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• 2003

It is well known that many pesticides possess hormonal activity, and affect the developments of wildlife and mammals including human. Currently, pyrethroid insecticides are in worldwide use to control in and outdoor pests, providing potential far environmental exposure. Hormonal activities of these pyrethroid insecticides, however, have been little studied, and the developmental effects of them were no reported. Therefore, we firstly examined the potential estrogenic activities of some pyrethroid insecticides (permethrin, cypermethrin, tetramethrin, deltamethrin, sumithrin, fenvalerate and bioallethrin) by immature rat uterotrophic assay, luciferase reporter gene assay and Calbindin-D$\sub$9k/ (CaBP-9k) gene expression assay. Uterine wet weights were increased by permethrin and the permethrin-induced weights were inhibited by ICI 182780 in the uterolrophic assay. On the other hand tetramethrin significantly reduced uterine and vaginal wet weights, and also inhibited the E2-induced weight increases at all doses tested. Cypermethrin and sumithrin had a tendency to increase uterine weights, although not statistically significant. Permethrin and cypermethrin dose-dependently increased the luciferase activity in reporter gene assay. Northern blot analysis showed that permethrin induced CaBP-9k mRNA expression whereas tetramethrin inhibted. Subsequent studies were conducted to investigate the possible developmental effects of four pyrethroid insecricides (permethrin, cypermethrin, sumithrin and teramethrin). Either diethlbestrol (DES) or 17${\beta}$ -estradiol (E2) was used as a reference control in this study. Pyrethroid insecticides were administered to Sprague Dawley rats via subcutaneous injection at 6 to 18 days of gestation or 1 to 5 days after birth. In utero treatment of permethrin (10mg/kg/day) in female rat resulted in significant increases in uterine and ovarian weights while significant decreases in serum E2 concentration, uterine and ovarian ER${\alpha}$ mRNA levels. Sumithrin and permethrin led to acceleration in vaginal opening of female rat, while delay in preputial separation of male after neonatal treatment. Anogenital distances of PND 18 were significantly reduced in sumthrin-treated, and permerhrin-treated male rats after neonatal treatment. All the pyrethroid insecticides tested caused significant increases in uterine weights on PND 18, while significant reductions in the first diestrus phase when neonataly treated. In addition, exposure to pyrethroids in neonatal period led to significant reduction in relative brain weight in female rat on PND 18, but its weight was recovered in diestrus phase. In summary, Our experimental data demonstrate the possibilities of developmental effects of pyrethroid insecticides via estrogenic or antiestrogenic activity.

• Biomolecules & Therapeutics
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• v.22 no.4
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• pp.347-354
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• 2014

Larrea nitida is a plant that belongs to the Zygophyllaceae family and is widely used in South America to treat inflammatory diseases, tumors and menstrual pain. However, its pharmacological activity remains unclear. In this study we evaluated the property of selective estrogen receptor modulator (SERM) of Larrea nitida extracts (LNE) as a phytoestrogen that can mimic, modulate or disrupt the actions of endogenous estrogens, depending on the tissue and relative amount of other SERMs. To investigate the property of SERM of LNE, we performed MCF-7 cell proliferation assays, estrogen response element (ERE)-luciferase reporter gene assay, human estrogen receptor (hER) binding assays and in vivo uterotrophic assay. To gain insight into the active principles, we performed a bioassay-guided analysis of LNE employing solvents of various polarities and using classical column chromatography, which yielded 16 fractions (LNs). LNE showed high binding affinities for $hER{\alpha}$ and $hER{\beta}$ with $IC_{50}$ values of $1.20{\times}10^{-7}$ g/ml and $1.00{\times}10^{-7}$ g/ml, respectively. LNE induced $17{\beta}$-estradiol (E2)-induced MCF-7 cell proliferation, however, it reduced the proliferation in the presence of E2. Furthermore, LNE had an atrophic effect in the uterus of immature rats through reducing the expression level of progesterone receptor (PR) proteins. LN08 and LN10 had more potent affinities for binding on $hER{\alpha}$ and ${\beta}$ than other fractions. Our results indicate that LNE had higher binding affinities for $hER{\beta}$ than $hER{\alpha}$, and showed SERM properties in MCF-7 breast cancer cells and the rat uterus. LNE may be useful for the treatment of estrogen-related conditions, such as female cancers and menopause.