• Development and Reproduction
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• v.12 no.1
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• pp.97-105
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• 2008

Vinclozolin (VCZ) is a systemic fungicide commonly used in fruits, vegetables and the wine industry. VCZ and its metabolites, butenoic acid (M1) and enanilide (M2) derivatives, act as anti-androgens through actions on the androgen receptor. Although there is growing body of evidence that VCZ's action as an endocrine disrupting chemical (EDC) in male reproductive physiology and pathphysiology, no evidence on the VCZ's EDC action in female is available yet. Previously we found that the prepubertal VCZ exposures could effectively delay the onset of puberty in female rats, suggesting the postponed or weakened activities of hypothalamus-pituitary-ovary (H-P-O) reproductive hormonal axis. The present study was performed to examine whether the VCZ administration affects the transcriptional activities of reproductive hormone-related genes in the same animal model. VCZ (10 mg/kg/day) was administered daily from postnatal day 21 (PND 21) through the day when the first vaginal opening (V.O.) was observed. To determine the transcriptional changes of reproductive hormone-related genes in hypothalamus and pituitary, total RNAs were extracted and applied to the semiquantitative reverse transcription polymerase chain reaction (RT-PCR). As a result, treatment with VCZ significantly lowered the transcriptional activity of nitric oxide synthase-2 (NOS-2) which is known to adjust gonadotropin-releasing hormone (GnRH) secretion in the hypothalamus (p<0.01). Similarly, the mRNA levels of KiSS-1, G protein-coupled receptor 54 (GPR54) and GnRH were significantly decreased in hypothalamus (p<0.01) from VCZ-treated group. As expected, the transcriptional activities of luteinizing hormone-${\beta}$ (LH-${\beta}$) and follicle stimulating hormone-${\beta}$ (FSH-${\beta}$) in the anterior pituitary from VCZ-treated group were also significantly lower than those from the control group. The present study indicates that(i) the inhibitory effect of VCZ exposure on the onset of puberty in immature female rats could be derived from the reduced transcriptional activities of gonadotropin subunits and their upstream modulators such as GnRH and KiSS-1 in hypothalamus-pituitary neuroendocrine axis, and (ii) these inhibitory effects could be mediated by NO signaling pathway.

• The Korean Journal of Pharmacology
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• v.30 no.1
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• pp.19-28
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• 1994

The effects of gonadoropin-releasing hormone (GnRH) and ovarian steroid hormones on the release of luteinizing hormone (LH) and its subunit mRNA levels were investigated in anterior pituitary cells in culture. LH concentration was measured by a specific radioimmunoassay and mRNA levels of u and $LH{\beta}$ subunits by RNA slot blot hybridization assay. GnRH stimulated LH release in a dose-dependent manner from cultured pituitary cells. However, the basal LH release in the absence of GnRH was not changed during the course of 24h culture, strongly suggesting that release of LH is directly controlled by GnRH. The treatment of the pituitary cells with GnRH increased $LH{\beta}$ subunit mRNA levels in a dose-dependent manner, reaching the maximum with $2\;{\times}\;10^{-10}M$ GnRH while no significant increase in ${\alpha}$ subunit mRNA levels was observed after GnRH treatment. Estradiol did not augment GnRH-induced LH release while progesterone augmented GnRH-induced LH release in a dose-dependent manner at the level of pituitary. However, estradiol and progesterone increased basal and GnRH-induced $LH{\beta}$ subunit mRNA levels in a dose-dependent manner. The treatment of estrogen antagonist, LYI17018 blocked the effect of estradiol on GnRH-induced $LH{\beta}$ subunit mRNA levels in a dose-dependent manner while progesterone antagonist, Ru486 tended to block the effect of progesterone on GnRH-induced $LH{\beta}$ subunit mRNA levels. It is therefore suggested that GnRH Playa a major role in LH release and subunit biosynthesis by influencing the steady state $LH{\beta}$ subunit mRNA loves and ovarian steroid hormones modulate subunit biosynthesis via directly acting on pituitary gonadotropes.

• Development and Reproduction
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• v.12 no.3
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• pp.251-259
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• 2008

The plasticizer di(2-ethylhexyl)phthalate(DEHP) is one of the most well known endocrine disrupting chemicals (EDCs) because of its strong anti-androgenic effects on the reproductive and developmental process in male rodents and human. The present study was performed to examine whether prepubertal exposure to DEHP can make any alteration during the maturation of accessory sex organs in male rats. As a result, there was no significant change in body weights, serum T levels and tissue weights except of seminal vesicle and ventral prostate in DEHP-treated animals compared to vehicle-treated ones. The seminal vesicle weights in high-dose group (200 mg/kg) were significantly lower than those from the control group (p<0.05), and ventral prostate weights were significantly lower than those from the control group (p<0.05) in both low-dose (20 mg/kg) and high-dose group. Histological studies revealed that the seminal vesicles from DEHP-treated groups showed reduced areas of mucosal folds. Pseudostratified columnar epithelia were observed in the ventral prostates of DEHP-treated samples while cuboidal epithelia were found in the control group. The transcriptional activities of ER-$\alpha$ in seminal vesicle from high-dose group (p<0.05) were significantly higher than those from the control group, and ER-$\beta$ expression was significantly decreased in low-dose group (p<0.05) compared to the control. In ventral prostate, ER-$\beta$ mRNA levels from low-dose group (p<0.05) were significantly lower than those from the control group, and significantly increased in high-dose group (p<0.01). AR expressions, however, were not significantly different in all experimental groups of both seminal vesicle and ventral prostate. In conclusion, the present study demonstrated that (i) adverse effect (s) of DEHP on sexual maturation during prepubertal period could be limited, (ii) seminal vesicle and prostate gland were sensitive targets to DEHP in prepubertal rats and (iii) the deleterious effects of DEHP might be mediated through ER-associated mechanism.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.4
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• pp.674-679
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• 2002

The toxicity and bioaccumulation of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) continues to be a focus of research in human and various species. The main human exposure is via the dietary route. This study was carried out to investigate the protective effect of Cornu Cervi Parvum extract on clinical parameters and hepatotoxicity in Sprague-Dawley rat (SD rat) accutely exposured to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Male SD rats received single intraperitoneal (ip) injection of TCDD (40 ㎍/kg), and administered 10 or 20 mg/kg/day of the ethanol extract oral injection for 4 weeks from 1 week before TCDD treatment. The gain in body weight was less in group treated with TCDD than in CON group, while that of C/H+ TCDD group (Cornu Cervi Parvum extract 20 mg/kg/day) increased. The decrease in spleen and testis weight caused by TCDD was prevented by Cornu Cervi Parvum extract 20 mg/kg/day. The fluctuation in BUN content, WBC and platelet count by TCDD intoxication were significantly attenuated by the ethanol extract treatment (20 mg/kg/day for 4 weeks). Treatments of rats with the extract (10 or 20 mg/kg/day) were significantly reduced AST and ALT levels compared with TCDD-treated group. Moderate swelling of hepatocytes, hyperchromatism, acidophilic cytoplasm and cytoplasmic vacuolation were observed in TCDD-treated animals (TCDD group). The administration of EtOH extract 10 or 20 mg/kg along with TCDD significantly alleviated the liver histopathological alteration induced by TCDD. These results suggest that Cornu Cervi Parvum extract can be useful as a protective agent against TCDD, an endocrine disruptor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1724-1731
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• 2009

This study was aimed to investigate the effect of phyto-extract fermented mixture (MP119) on the male sexual functions. The MP119 was evaluated for anti-impotency and anti-hypertensive effects via ACE (angiotensin converting enzyme) or PDE (phosphodiesterase) inhibition assay. $IC_{50}$ values of MP119 against ACE and PDE were 241.3${\pm}$35.5 ppm and 372.2${\pm}$33.8 ppm, respectively. To investigate the effect of testosterone expression by MP119, we performed cell media test using mouse Leydig-derived TM3 cells. Production of testosterone in TM3 cell was increased by MP119. Also, NO (nitric oxide) production of HUVEC (human umbilical vein endothelial cell) was increased when MP119 was added to the cultures. Forty male ICR mice were divided into 4 groups. MP119 was orally intubated for 7 days to group 1 and 3, and same volume of vehicle to group 2 and 4 as controls. After that, group 3 and 4 were intraperitoneally injected cadmium chloride at a single dose of 2 mg/kg. On the 8th experimental day, weights of testis, epididymis and seminal vesicle, number of sperm, concentrations of serum testosterone and cGMP were determined. The number of sperm, the concentrations of testosterone and cGMP were significantly increased in two experimental groups (group 1, 3). These results suggest that MP119 enhanced the sexual function of male mice, and could protect the sexual organs from the cadmium chloride as one of the endocrine disrupters.

• Clinical and Experimental Pediatrics
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• v.52 no.1
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• pp.111-118
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• 2009

Puopose : Exposure to dietary phytoestrogens such as genistein during early childhood is a growing public health concern. We examined the effect of early exposure to genistein on sexual maturation in immature rats. Methods : Weaning (3wk-old) Sprague-Dawley female rats were assigned to three groups (n=6 for each): fed by high dose of genistein (100 mg/kg/d), low dose of genistein (10 mg/kg/d) and control group. First vaginal opening (VO) day was observed. Structural alterations in the ovary and uterus were assessed by histologically. Expression of genes of $ER{\alpha}$, $ER{\beta}$, and progesterone receptor (PR) in the ovary and uterus were investigated by RT-PCR. Results : High genistein group had earlier VO than control and low genistein group. Graafian follicles and corpora lutea were observed from the ovary of genistein-treated groups, while primary, secondary follicles and small atretic follicles were observed in the control group. Hypertrophy of luminal and glandular uterine epithelia were found in the genistein-treated groups while poor development of gland and fewer myometrial cell layers were evident in control group. In ovary, the transcriptional activities of $ER{\alpha}$ and $ER{\beta}$ were higher in high genistein group than in controls. In uterus, the transcriptional activities of $ER{\alpha}$, $ER{\beta}$ and PR were higher in low genistein group than in controls. Conclusion : Acute exposure to genistein during the prepubertal period could activate the reproductive endocrine system resulting in the early onset of puberty in female rats. Further clinical investigation on the effect of genistein on the sexual maturation in children is warranted.

• Molecular & Cellular Toxicology
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• v.4 no.4
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• pp.348-354
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• 2008

Bisphenol A (BPA), an environmental endocrine disrupter, enters the human body continuously in food and drink. Young children are likely to be more vulnerable than adults to chemical exposure due to the immaturities of their organ systems, rapid physical development, and higher ventilation, metabolic rates, and activity levels. The direct effect of BPA on peripheral tissue might also be of importance to the development of insulin resistance. However, the influence that BPA has on insulin signaling molecules in skeletal muscle has not been previously investigated. In this study, we examined the effect of BPA on fasting blood glucose (FBG) in post-weaned Wistar rats and on insulin signaling proteins in C2C12 skeletal muscle cells. Subsequently, we investigated the effects of BPA on insulin-mediated Akt phosphorylation in C2C12 myotubes. In rats, BPA treatment (0.1-1,000 ng/mL for 24 hours) resulted in the increase of FBG and plasma insulin levels, and reduced insulin-mediated Akt phosphorylation. Furthermore, the mRNA expression of insulin receptor (IR) was decreased after 24 hours of BPA treatment in C2C12 cells in a dose-dependent manner, whereas the mRNA levels of other insulin signaling proteins, including insulin receptor substrate-1 (IRS-1) and 5'-AMP-dependent protein kinase (AMPK), were unaffected. Treatment with BPA increased GLUT4 expression and protein tyrosine phosphatase 1B (PTP1B) activity in C2C12 myotubes, but not in protein levels. We conclude that exposure to BPA can induce insulin resistance by decreasing IR gene expression, which is followed by a decrease in insulin- mediated Akt activation and increased PTP1B activity.

• Journal of Pharmacopuncture
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• v.25 no.2
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• pp.106-113
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• 2022

Objectives: Herbal medicine is a worldwide health topic. Vitex agnus-castus L. (VAC) is a popular plant used for gynecologic problems due to its hormonal effects. The aim of this study is to reveal VAC extract effect on fetus when this herb is used started from antenatal period or during pregnancy. Methods: Performed from starting day of January 2019 till February 2019, 48 rats were assigned in randomly divided eight-member six groups: control (C1), treated group with 365 mg/kg VAC from initiation of insemination (T1) and 30 days prior to pregnancy (T2), control that underwent caesarean section on 15^th day of gestational age (C2) and treated group with 365 mg/kg VAC from initiation of insemination (T3) and 30 days prior to pregnancy (T4) that underwent caesarean section. Weight, sex and number of fetuses, abortion and still birth rate and estradiol level were evaluated using t-test by SPSS software. Results: We showed increased weight among T1 group considering totally and sex-dependent which is significant (all p-value < 0.05). We also detected significantly decreased weight in T2 in total (p-value < 0.0001) and when considering female fetuses (0.043) but not males (0.17). Although the results showed slightly non-significant increased weight among fetuses of T3 (totally or based on the fetus sex) compared to the control group (C2), T4 group had statistically decreased weight compared to control group. Pregnancy rate and pregnancy outcome were affected by VAC usage. The time of VAC initiation also affected live birth and abortion rates. Conclusion: VAC extract may affect pregnancy rate, live birth rate, abortion and stillbirth rates. Its effect on the weight and the sex showed dual pattern depends on the time of initiation and pregnancy trimester of evaluation. Prescribing this medicinal plant for patients being prone to pregnancy should be with caution. Further study is recommended.

• Journal of Food Hygiene and Safety
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• v.21 no.2
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• pp.100-106
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• 2006

The use of underarm and body care cosmetics with oestrogenic chemical excipients (particularly the parabens) and the hypothesized association with breast cancer incidence, particularly in women. It is noted that the type of cosmetic product is irrelevant (e.g. antiperspirant/deodorant versus body lotion, moisturizers or sprays versus creams) and attention must focus on issues of actual exposure to chemicals through continued dermal application of body care products and the endocrine/hormonal activity and toxicity of the chemicals in the formulations. To evaluate the estrogenic activities of parabens such as ethylparaben, butylparaben, propylparaben, isobutylparaben and isopropylparaben, we used recombinant yeasts containing the human estrogen receptor [Saccharomyces cerevisiae ER+LYS 8127], human breast cancer MCF-7 cell lines and human estrogen receptor ${\alpha}\;and\;{\beta}$. In E-screen assays, isopropylparaben is the most estrogenic paraben, and in ER competition assay, isobutylparaben is the most estrogenic paraben. We evaluated isopropylparaben was most active in the recombinant yeast assay, followed by propylparaben, ethylparaben, isobutylparaben and butylparaben. Results from this study demonstrate that parabens are observed in human endocrine system. Therefore, we have shown that the parabens is induced the estrogenic activities similar to $17{\beta}$-estradiol and Bisphenol-A.

• Korean Journal of Poultry Science
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• v.29 no.4
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• pp.243-247
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• 2002

A study was conducted to investigate the effect of induced molting on the relative weight and hormone levels of thyroid, ovary, and adrenal glands in spent laying hens. Three hundred sixty 77-wk-old, Babcock White hens were divided into 36 experimental units of 10 hens each and induced to molt for seven weeks. A diet containing 16% CP and 2,800 kcal ME/kg was fed ad libitum from 84 to 126 weeks of age. Thirty-six birds were randomly selected for blood collection and slaughtered at Pre-molt, 5% egg Production, Peak, and end Phase of the egg Production. Weights of the thyroid, ovary, adrenal glands, and plasma T3, T4, cortisol, and estradiol contents were measured at each stage. Weight of the thyroid reached its highest level at 5% e99 Production stage. The ovary weight was greatly reduced during molting, but started to increase after induced molting until the end of the egg Production Phase (P<0.05). Plasma T3,T4 and cortisol were found to be the highest at the start of the Post-molt Production stage, but reached their minimum at the end Phase of e99 Production. Plasma estradiol was the lowest at the 5% egg Production stage. The Present study demonstrated that molting is a complex Process that require the involvement of endocrine glands to trigger their specific hormones, which play a key role in molt induction.