• Toxicological Research
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• v.16 no.1
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• pp.27-31
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• 2000

Recently, there is a worldwide concern that a great number of man-made chemicals have a hormone-like action both in humans and in animals. EPA and OECD are developing screening programs using validated test systems to determine whether certain substances may have an effect on humans. In the present study, the establishment of in vivo short-term test system for pubertal female assay with thyroid to detect endocrine disrupting chemicals was tried using a model substance, methoxychlor (MC), a chlorinated hydrocarbon insencticide. Forty female rats were assigned to four groups. MC was administered at dose levels of 0, 8, 40 and 200mg/kg by gavage to female rats from day 21 post partum to the completion of vaginal opening. We evaluated body weight change, age at vaginal opening, onset of estrous cyclicity, age at first esturs, ovary weight, and serum concentrations of thyroxine and thyroid stimulating hormone in female rats. The age at vaginal opening of females receiving 40 200mg/kg was significantly younger than control. The onset of estrus cyclicity and age at first estrus of females receiving 200mg/kg was also younger than controls. There was no effect of treatment on body weight, ovary weight, and hormone concentration. Based on these results, it can be concluded that application of MC at dose level of 40mg/kg affects the vaginal opening and application of MC at dose level of 200mg/kg accelerates the vaginal opening and the onset of estrus cylicity.

• Korean Journal of Pharmacognosy
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• v.37 no.4 s.147
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• pp.324-330
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• 2006

The aim of this study was to evaluate the effects of Artemisia Princeps Var. Orientalis (AP) on serum lipids and the collagen content of the connective tissues in ovariectomized rats. From day 2 until day 37 after the ovariectomy, Sprague-Dawley female rats were randomly assigned to the following groups: sham-operated rats (Sham), ovariectomized control rats (OVX-control), and ovariectomized rats supplemented with the AP 50 mg/kg bw/day (OVX-AP). The AP ethanol extracts were orally administrated 1 mL per day. The OVX rats were significantly heavier than the sham-operated rats at all time points, but supplementation with the AP extracts tended to gain weight less than OVX-control. Although total-cholesterol was increased at OVX-control, supplementation with the AP extracts tended to result in less than OVX-control. Triglyceride was significantly decreased after supplemented with the AP extracts (p<0.05). HDL-cholesterol is appeared higher AP extracts group than OVX-control. According to the results, we could know the fact that AP extracts were effective on serum lipids content throughout decreasing total-cholesterol, triglyceride and increasing HDL-cholesterol in ovariectomized rats. Supplementation with the AP extracts prevented a decrease in the collagen level in bone and cartilage tissues. These results are consistent with the conclusions based on the estrogenic activities of AP. Therefore, it may be used to possibly improve the quality of life in menopausal women.

• Journal of Microbiology and Biotechnology
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• v.26 no.5
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• pp.967-974
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• 2016

Zearalenone (ZEA) is an estrogenic mycotoxin that is produced by several Fusarium species, including Fusarium graminearum. One of the ZEA biosynthetic genes, ZEB2, encodes two isoforms of Zeb2 by alternative transcription, forming an activator (Zeb2L-Zeb2L homooligomer) and an inhibitor (Zeb2L-Zeb2S heterodimer) that directly regulate the ZEA biosynthetic genes in F. graminearum. Cyclic AMP-dependent protein kinase A (PKA) signaling regulates secondary metabolic processes in several filamentous fungi. In this study, we investigated the effects of the PKA signaling pathway on ZEA biosynthesis. Through functional analyses of PKA catalytic and regulatory subunits (CPKs and PKR), we found that the PKA pathway negatively regulates ZEA production. Genetic and biochemical evidence further demonstrated that the PKA pathway specifically represses ZEB2L transcription and also takes part in posttranscriptional regulation of ZEB2L during ZEA production. Our findings reveal the intriguing mechanism that the PKA pathway regulates secondary metabolite production by reprograming alternative transcription.

• Journal of Applied Biological Chemistry
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• v.51 no.6
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• pp.253-261
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• 2008

Isoflavone daidzein is a phytoestrogen widely distributed in Leguminosae and is especially rich in the soybean. The C6-C3 (rings B and C) unit of isoflavones is derived from the phenylpropanoid pathway and the remaining C6 (ring A) unit is from the polyketide pathway. This unique carbon skeleton is the result of isomerization of the flavone catalyzed by the isoflavone synthase, a cytochrome P450 enzyme. The isoflavones daidzein and genistein are present in the plant mostly in the glucosylated forms. However, in the human intestine, the glycosidic linkage is broken, and the free form is uptaked into blood stream. The free form is further metabolized into various reduction products to end up at the equol, which is known to have the most potent estrogenic effect among the metabolites. Several human intestinal bacteria that can convert daidzein into equol have been described, and the study into the chemistry and biochemistry of the daizein reduction would be rewarding to the improvement of the human health.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.640-643
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• 2000

Soybeans contain the phytoestrogens genistein and daidzein, their glucosides genistin and daidziin and coumesterol. These isflavonoid compounds are capable of producing an estrogenic response in a number of diverse species. This study determined optimum conditions for extraction of isoflavones in defatted soybean meal. Extraction of isoflavones was conducted at various conditions such as difference concentrations of extraction solvent, temperature, time and pH to extact. The most optimum extraction conditions was achieved at 75% ethanol, $80^{\circ}C$, pH4 and extract for three hours. In addition. isoflavones with high purity were separated by adding up to 4%(w/v) of calcium chloride dihydrate.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.4
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• pp.442-449
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• 2017

Adenophora triphylla var. japonica extract has been reported to have estrogenic activity and beneficial effects in postmenopausal women requiring estrogen replacement therapy. This study investigated the effects of A. triphylla extract on cognitive function in ovariectomized mice. Water extracts from A. triphylla were administrated to ovariectomized mice fed a high fat diet for 6 weeks. The step through latency time in the passive avoidance test was shortened in ovariectomized mice as compared with sham-operated mice. However, administration of A. triphylla extracts had a tendency to prolong the latency time in ovariectomized mice. Moreover, A. triphylla supplementation caused a significant decrease in mean escape latency in the water maze test. These results indicate that A. triphylla could be used to improve estrogen deficiency-related learning and memory impairments in postmenopausal women.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.115.1-115.1
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• 2003

Cadmium, a human carcinogen, can induce apoptosis in various cell lines. Despite extensive research, the mechanisms of cadmium-induced apoptosis are poorly understood, and its toxicity and estrogenic potential in human are not clear. This study was performed to investigate the apoptotic activities of cadmium on two human breast cancer cell lines: MCF-7 cells, an estrogen receptor (ER) positive cell line, and MDA-MB-231 cells, an ER negative cell line. Both cells were treated with $CdCl_2$ 100$\mu$M for 12hrs, and the spoptosis was determined by DNA fragmentation, DAPI staining, and expression of caspase-9. (omitted)

• Natural Product Sciences
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• v.21 no.1
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• pp.34-41
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• 2015

The objective of this study is to characterize a toxicity of Epimedii Herba (EH) in F344 rats and to find a dose levels for the 13 weeks toxicity study. EH is well known as medicinal herb in many Asian countries for traditional medicines of antibacterial and antiviral effects, estrogenic and antiestrogenic effects, and for treatment of osteoporosis, hypotensives, fatigue, kidney disorders, and related complications. However, the indispensable and basic information of toxicological evaluation of EH extract is insufficient to support its safe use. Therefore, we conducted toxicological evaluation of this drug in compliance with OECD and MFDS guideline in this study. The extract of EH was administered orally to F344 rats at dose levels of 0, 500, 1000, 2000, 3500, and 5000 mg/kg/day for 2 weeks. Each group was composed of 5 male and female rats. In this study, there were no treatment of EH-related adverse changes in clinical observations, mortality, body weights, food consumption, urinalysis, gross finding at necropsy, and organ weight examination. Total red blood cell count, hematocrit, mean corpuscular hemoglobin concentration, total cholesterol, and phospholipid were decreased in males and females at 5000 mg/kg/day compared to the control animals. Mean corpuscular volume and reticulocyte counts were increased in males and females at 5000 mg/kg/day compared to control animals. Therefore, we recommend that dose level of 5000 mg/kg/day is a highest treatment group in 13-week EH extract exposure study for further toxicity assessment.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5445-5450
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• 2012

Although benign uterine leiomyomata (LMA) is the most common reproductive tumor in premenopausal women, its etiology is largely unknown. We aimed in the present study to demonstrate the potential role of environmental factors with estrogenic activity in tumor etiology by focusing on the role of aryl hydrocarbon receptor (AhR) which mediates the effects of many environmental endocrine disruptors and contributes to the loss of normal ovarian function in polluted environments. This case-control study aimed to compare the interactions between AhR and lifestyle factors in a clinical setting for the first time among 138 newly diagnosed LMA patients and 138 normal controls who lived in Tehran and Mashhad, respectively, during the last 10 years. To conduct immunohistochemical studies using appropriate monoclonal antibodies, 30 cases were selected retrospectively from 2009-2011 from the pathology departments of two university hospitals in Tehran. Although the levels of sex steroid receptors were similar in adjacent myometrium and uterine leiomyomas of all cases, AhR was significantly overexpressed (p=0.034, OR=1.667) in uterine LMA and this overexpression was correlated with living in Tehran [(p=0.04, OR=16 (1.216-210.58)], smoking[P=0.04, OR=2.085 (1.29-3.371)], living near polycyclic aromative hydrocarbon producing companies [p=0.007, OR=2.22 (1.256-3.926)] and eating grilled meat [p=0.042, OR=1.28 (1.92-3.842)]. Our study contributes to the understanding of the effects of EDCs on AhR levels as well as women's health and points out possible risk factors for the development and growth of uterine LMA. It seems that the development of LMA could be the result of interactions between hormonal and environmental factors.

• BMB Reports
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• v.38 no.3
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• pp.300-306
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• 2005

Tamoxifen citrate is an anti-estrogenic drug used for the treatment of breast cancer. It showed a degree of hepatic carcinogenesis, when it used for long term as it can decrease the hexose monophosphate shunt and thereby increasing the incidence of oxidative stress in liver rat cells leading to liver injury. In this study, a model of liver injury in female rats was done by intraperitoneal injection of tamoxifen in a dose of 45 mg/kg body weight for 7 successive days. This model produced a state of oxidative stress accompanied with liver injury as noticed by significant declines in the antioxidant enzymes (glutathione-S-transferase, glutathione peroxidase and catalase) and reduced glutathione concomitant with significant elevations in TBARS (thiobarbituric acid reactive substance) and liver transaminases; sGPT (serum glutamate pyruvate transaminase) and sGOT (serum glutamate oxaloacetate transaminase) levels. The oral administration of dimethyl dimethoxy biphenyl dicarboxylate (DDB) in a dose of 200 mg/kg body weight daily for 10 successive days, resulted in alleviation of the oxidative stress status of tamoxifen-intoxicated liver injury in rats as observed by significant increments in the antioxidant enzymes (glutathione-S-transferase, glutathione peroxidase and catalase) and reduced glutathione concomitant with significant decrements in TBARS and liver transaminases; sGPT and sGOT levels. The administration of DDB before tamoxifen intoxication (as protection) is more little effective than its curative effect against tamoxifen-induced liver injury. The data obtained from this study speculated that DDB can mediate its biochemical effects through the enhancement of the antioxidant enzyme activities and reduced glutathione level as well as decreasing lipid peroxides.