• Development and Reproduction
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• v.13 no.4
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• pp.249-256
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• 2009

The estrogen receptor-related receptors (ERRs) are a group of nuclear receptor superfamily of transcription factors. ERRs and estrogen receptors (ERs) have overlapping affinities for coactivators and DNA binding sites, but differ markedly in ligand binding and activation. The three mammalian ERR genes have been implicated in diverse physiological processes ranging from placental development to maintenance of bone density, whereas the molecular diversity, function, and regulation of ERRs in non-mammalian species are not well understood. In the present study, to investigate the involvement of ERR in transcription and embryogenesis in marine invertebrates, a cDNA encoding ERR (SnERR) was cloned from the gonad in Strongylocentrotus nudus, by polymerase chain reaction (PCR). The amino acid sequence of SnERR showed high homology with that of S. purpuratus (91%). A phylogenetic tree clearly showed that SnERR is a member of the ERR family and clustered in echinodermata group as supported by a high bootstrap value. We examined gene expression of SnERR during embryonic development of S. nudus using real-time PCR. During the embryonic development, the mRNA of ERR was significantly high levels in early development stages (4~64 cell) and larval stages. The SnERR slightly activated transcription through the classical estrogen response elements (EREs) in the presence of genistein. In addition, peroxisome proliferator-activated receptor $\gamma$ coactivator (PGC)-$1\alpha$ knwon as a coactivator of ERR enhanced the snERR-mediated transactivation, suggesting that the PGC-$1\alpha$ is a coactivator of SnERR.

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

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.1
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• pp.89-94
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• 2002

Effect of Gamisamul-tang(GS) on body weight, uterine weight, splenial weight, serum and estrogen receptor-α (ER-α) in kidney were investigated in ovariectomized(OVX) rats. Female Sprague -Dawley rats with a body weight of 220 g were undergone ovariectomy or sham operation. The ovariectomy caused significant decrease in serum levels of HDL-cholesterol and in uterine weight compared to those of sham-operated animals. while caused significant increase in serum levels of total cholesterol, LDL-cholesterol, triglyceride, body weight and in splenial weight. In contrast, administration of OVX rats with the GS significantly elevated serum levels of HDL-cholesterol and uterine weight, but significantly depressed serum levels of total cholesterol, LDL-cholesterol, triglyceride, body weight and in splenial weight. ER-α localized in the kidney vessel endothelial cells and its expression was increased by ovariectomy and decreased by administration of OVX rats with the GS. Our results suggest that a possible protective effect of as against hyperlipidemia in postmenopausal cardiovascular disease and as increase the estrogen-estrogen receptor romp/ex in the kidney vessel endothelial cells.

• The Journal of Korean Obstetrics and Gynecology
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• v.25 no.3
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• pp.71-84
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• 2012

Objectives: GG is the EtOH fraction of extract of Pueraria lobata. In this study, we aimed to elucidate a possibility that GG reduce obesity and obesity-derived complications such as cardiovascular and metabolic disease. Methods: The effects of GG on the estrogen-deficient obese rats and the level of gene expression in muscle of rats were investigated. Results: GG decreased body weight in obese rats with estrogen deficiency. GG increased leptin gene expression in obese rats with estrogen deficiency. GG decreased TNFa gene expression in obese rats with estrogen deficiency. And GG increased PPAR-gamma, PGC-1a, Prdx6, FDFT1, and ACC gene expression of those in obese rats. Conclusions: We conclude GG might reduce body weight and regulate gene expression of muscle in obese rats.

• Bulletin of the Korean Chemical Society
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• v.29 no.6
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• pp.1107-1114
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• 2008

It is important to identify selective ligands for the estrogen receptor subtypes ER$\alpha$ or ER$\beta$ to evaluate them as pharmaceutical targets in breast cancer. To develop ER$\beta$-selective ligands as PET imaging agents, a series of aryl indazole estrogen analogues substituted at the C3 position with fluoroethyl and fluoropropyl groups were synthesized and evaluated for their relative binding affinities and selectivities for ER$\alpha$ vs ER$\beta$. The fluoroethylated indazole estrogen (FEIE, 1i) and fluoropropylated indazole estrogen (FPIE, 1h) showed 41- fold and 17-fold ER$\beta$/ER$\alpha$ selectivity, respectively. However, their binding affinities to ER$\alpha$ and ER$\beta$ were very low.

• Clinical and Experimental Reproductive Medicine
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• v.18 no.2
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• pp.197-199
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• 1991

The role of estrogen in calcium metabolism has not been well documented. To further investigate the effects of endogenous estrogen on the calcium regulating hormones in women, we correlated the changes of estrogen level with those of calcium regulating hormones during ovulation induction in 12 hypogonadal and 8 normally menstruating women. During ovulation induction, the serum leveles of estradiol rose from 40.0 to 831.0pg/ml. There were no significant changes in the serum leveles of total calcium, inorganic phosphorus, parathyroid hormone, calcitonin. However, 1, $25-(OH)_2D_3$ rose significantly from 31.0 to 47.2pg.ml as the endogenous $E_2$ increaed (p<0.005).

• YAKHAK HOEJI
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• v.54 no.6
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• pp.522-528
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• 2010

This study was designed to examine the effect of estrogen deficiency on the metabolism of ethanol in ovariectomized rats. Female rats were assigned to an ovariectomy (OVX) and a sham (SHAM) surgery group. Gain body weight was greater in incresed in OVX group and especially uterus weight significantly decrease depending on the concentration of estrogen after 3 month of ovariectomy. Ethanol at the tolerative dose (6 g/kg) was injected to rats by oral administration to measure the concentration of ethanol in blood. The area under the blood concentration time curve (AUC) was significantly lower in OVX group than SHAM group. The significant decrease in AUC in OVX group indicates that the estrogen deficiency leads to changes of the factors related to ethanol metabolism. Activity of hepatic alcohol dehydrogenase was not significantly influenced by the ovariectomy and also the ethanol elimination rate in vivo was not different. Cytochrome P450 isozymes did not show any changes except CYP 1A1 and 2E1. Level of hepatic glutathione in OVX group was higher after treatment of ethanol. Therefore the reduction of AUC appears not to be directly associated with the difference of ethanol metabolizing enzyme, but to be related with the physical factors like body weight.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.475-479
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• 1997

A decrease in the circulating levels of estrogen, occuring as a consequence of post menopausal decline or from surgical ovariectomy, results in an accelerated loss of bone. Estrogen has been shown to stimulate lysyl oxidase activity, and the treatment with estrogen increased the pyridinium content of cortical bone. a trivalent mature cross-links collagen fibrils named pyridinoline, which is especially abundant in collagen of cartilage and bone, markedly increases with growth in humans and rats. The main aim of this study was to examine the increased bone loss caused by ovariectomy through monitoring the concentrations of the collagen and the pyridinium cross-links of collagen, pyridinoline. The ovariectomized rats, 4 weeks old, were divided at random into two or three groups of 5. Ovariectomies were carried out on both of the saline-treated group(OVX(NH)) and the estrogen-treated group(OVX(H)) using the dorsal approach and sham operations were performed on the sham-operated group(sham). They were maintained under identical conditions for 4 or 8 weeks and were allowed free access to food and water. it was observed that there was no significant difference between the control group and the sham-operated group, however, the control group had a higher content of collagen than the saline-treated group after 4 weeks and 8 weeks. Based on these results, iot is supposed that estrogen can enhance collagen synthesis and affects the pyridinoline formation in collagen fibrils through stimulating lysyl oxidase activity.

• Toxicological Research
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• v.27 no.2
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• pp.85-93
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• 2011

Selective estrogen receptor modulators (SERMs) are synthetic molecules which bind to estrogen receptors (ER) and can modulate its transcriptional capabilities in different ways in diverse estrogen target tissues. Tamoxifen, the prototypical SERM, is extensively used for targeted therapy of ER positive breast cancers. Unfortunately, the use of tamoxifen is associated with acquired resistance and some undesirable side effects. This study investigated the availability of the conventional SERMs on the TAM-resistance breast cancer cells. SERMs showed more effectiveness in MCF-7 cells than tamoxifen resistant cells, except toremifene and ospemifene. Especially, toremifene was more efficacious in tamoxifen resistant cells than MCF-7. Ospemifene had similar cytotoxic activity on the two types of breast cancers. The other SERMs used in this experiment didn't inhibit efficiently the proliferation of tamoxifen resistant cells. These results support the possibility to usage of toremifene on tamoxifen resistant cancer. The effectiveness by toremifene on tamoxifen resistant cells might be different pathways from the apoptosis and the autophagy. Further study should be needed to elucidate the underlying mechanism of effect of toremifene on tamoxifen resistant cancer.

• Journal of Korean Biological Nursing Science
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• v.10 no.1
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• pp.80-87
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• 2008

Purpose: Hypoestrogenism caused by ovariectomy, disease, or menopause is associated with increased obesity in women. Altered fat distribution and weight gain are consequences of menopausal hypoestrogenism, but the mechanisms responsible are not completely known. This study examined the effect of estrogen on obesity in ovariectomized rats. Method: The groups of female rats were 4 weeks post ovariectomy (OVX) or, 4 weeks post-sham operation (SHAM), and 2 weeks post ovariectomy followed by 2 weeks replacement with estradiol benzoate (ER-$16{\mu}g$/kg, subq, qd). Serum ghrelin level was measured by radioimmunoassay (RIA). The expression of adrenergic receptors in adipose tissue was measured by Western blotting assay. Result: OVX significantly increased body weight, serum cholesterol. Two weeks estrogen replacement reduced body weight accompanied by the increment of serum ghrelin and the reduction of the receptor ratio of adrenergic ${\alpha}_{2A}/{\beta}_1$, and ${\alpha}_{2A}/{\beta}_3$. Conclusion: We provide evidence that estrogen reduces obesity through the altered receptor ratio of adrenergic ${\alpha}_{2A}/{\beta}_1$, and ${\alpha}_{2A}/{\beta}_3$ in adipose tissue in ovariectomized rats.