Sample records for emitting estrogen receptor-directed

  1. Bromine-80m-labeled estrogens: Auger-electron emitting, estrogen receptor-directed ligands with potential for therapy of estrogen receptor positive cancers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    DeSombre, E.R.; Mease, R.C.; Hughes, A.

    1988-01-01

    A triphenylbromoethylene, 1,1-bis(p-hydroxyphenyl)-2-bromo-2-phenylethylene, Br-BHPE, and a bromosteroidal estrogen, 17..cap alpha..- bromovinylestradiol, BrVE/sub 2/, were labeled with the Auger electron emitting nuclide bromine-80m, prepared by the (p,n) reaction with /sup 80/Se. To assess their potential as estrogen receptor (ER) directed therapeutic substrates the bromine-80m labeled estrogens were injected into immature female rats and the tissue distribution studied at 0.5 and 2 hours. Both radiobromoestrogens showed substantial diethylstilbesterol (DES)-inhibitable localization in the ER rich tissues, uterus, pituitary, ovary and vagina at both time points. While the percent dose per gram tissue was higher for the Br-BHPE, the BrVE/sub 2/ showed higher tissuemore » to blood ratios, especially at 2 hr, reflecting the lower blood concentrations of radiobromine following administration of the steroidal bromoestrogen. Comparing intraperitoneal, intravenous and subcutaneous routes of administration for the radiobromine labeled Br-BHPE, the intraperitoneal route was particularly advantageous to provide maximum, DES-inhibitable concentrations in the peritoneal, ER-rich target organs, the uterus, ovary and vagina. While uterine concentrations after BrBHPE were from 10--48% dose/g and after BrVE/sub 2/ were 15--25% dose/g, similar treatment with /sup 80m/Br as sodium bromide showed uniform low concentrations in all tissues at about the levels seen in blood. The effective specific activity of (/sup 80m/Br)BrBHPE, assayed by specific binding to ER in rat uterine cytosol, was 8700 Ci/mmole. 23 refs., 9 figs., 2 tabs.« less

  2. Efavirenz directly modulates estrogen receptor and induces breast cancer cell growth

    PubMed Central

    Sikora, Matthew J.; Rae, James M.; Johnson, Michael D.; Desta, Zeruesenay

    2010-01-01

    Objectives Efavirenz-based HIV therapy is associated with breast hypertrophy and gynecomastia. Here, we tested the hypothesis that efavirenz induces gynecomastia through direct binding and modulation of estrogen receptor (ER). Methods To determine the effect of efavirenz on growth, the estrogen-dependent, ER-positive breast cancer cell lines MCF-7, T47D and ZR-75-1 were treated with efavirenz under estrogen-free conditions in the presence or absence of the anti-estrogen ICI 182,780. Cells treated with 17β-estradiol in the absence or presence of ICI 182,780 served as positive and negative controls, respectively. Cellular growth was assayed using the crystal violet staining method and an in vitro receptor binding assay was used to measure efavirenz’s ER binding affinity. Results Efavirenz induced growth in MCF-7 cells with an estimated EC50 of 15.7µM. This growth was reversed by ICI 182,780. Further, efavirenz binds directly to ER (IC50 of ~52µM) at roughly 1000-fold higher concentration than observed with E2. Conclusions Our data suggest that efavirenz-induced gynecomastia may be due, at least in part, to drug-induced ER activation in breast tissues. PMID:20408889

  3. Estrogen regulation of chicken riboflavin carrier protein gene is mediated by ERE half sites without direct binding of estrogen receptor.

    PubMed

    Bahadur, Urvashi; Ganjam, Goutham K; Vasudevan, Nandini; Kondaiah, Paturu

    2005-02-28

    Estrogen is an important steroid hormone that mediates most of its effects on regulation of gene expression by binding to intracellular receptors. The consensus estrogen response element (ERE) is a 13bp palindromic inverted repeat with a three nucleotide spacer. However, several reports suggest that many estrogen target genes are regulated by diverse elements, such as imperfect EREs and ERE half sites (ERE 1/2), which are either the proximal or the distal half of the palindrome. To gain more insight into ERE half site-mediated gene regulation, we used a region from the estrogen-regulated chicken riboflavin carrier protein (RCP) gene promoter that contains ERE half sites. Using moxestrol, an analogue of estrogen and transient transfection of deletion and mutation containing RCP promoter/reporter constructs in chicken hepatoma (LMH2A) cells, we identified an estrogen response unit (ERU) composed of two consensus ERE 1/2 sites and one non-consensus ERE 1/2 site. Mutation of any of these sites within this ERU abolishes moxestrol response. Further, the ERU is able to confer moxestrol responsiveness to a heterologous promoter. Interestingly, RCP promoter is regulated by moxestrol in estrogen responsive human MCF-7 cells, but not in other cell lines such as NIH3T3 and HepG2 despite estrogen receptor-alpha (ER-alpha) co transfection. Electrophoretic mobility shift assays (EMSAs) with promoter regions encompassing the half sites and nuclear extracts from LMH2A cells show the presence of a moxestrol-induced complex that is abolished by a polyclonal anti-ERalpha antibody. Surprisingly, estrogen receptor cannot bind to these promoter elements in isolation. Thus, there appears to be a definite requirement for some other factor(s) in addition to estrogen receptor, for the generation of a suitable response of this promoter to estrogen. Our studies therefore suggest a novel mechanism of gene regulation by estrogen, involving ERE half sites without direct binding of ER to the

  4. Impact of Estrogens and Estrogen Receptor Alpha (ESR1) in Brain Lipid Metabolism.

    PubMed

    Morselli, Eugenia; de Souza Santos, Roberta; Gao, Su; Ávalos, Yenniffer; Criollo, Alfredo; Palmer, Biff F; Clegg, Deborah J

    2018-03-06

    Estrogens and their receptors play key roles in regulating body weight, energy expenditure, and metabolic homeostasis. It is known that lack of estrogens promotes increased food intake and induces the expansion of adipose tissues, for which much is known. An area of estrogenic research that has received less attention is the role of estrogens and their receptors in influencing intermediary lipid metabolism in organs such as the brain. In this review, we highlight the actions of estrogens and their receptors in regulating their impact on modulating fatty acid content, utilization, and oxidation through their direct impact on intracellular signaling cascades within the central nervous system.

  5. Retinoid X receptor and peroxisome proliferator-activated receptor activate an estrogen responsive gene independent of the estrogen receptor.

    PubMed

    Nuñez, S B; Medin, J A; Braissant, O; Kemp, L; Wahli, W; Ozato, K; Segars, J H

    1997-03-14

    Estrogen receptors regulate transcription of genes essential for sexual development and reproductive function. Since the retinoid X receptor (RXR) is able to modulate estrogen responsive genes and both 9-cis RA and fatty acids influenced development of estrogen responsive tumors, we hypothesized that estrogen responsive genes might be modulated by RXR and the fatty acid receptor (peroxisome proliferator-activated receptor, PPAR). To test this hypothesis, transfection assays in CV-1 cells were performed with an estrogen response element (ERE) coupled to a luciferase reporter construct. Addition of expression vectors for RXR and PPAR resulted in an 11-fold increase in luciferase activity in the presence of 9-cis RA. Furthermore, mobility shift assays demonstrated binding of RXR and PPAR to the vitellogenin A2-ERE and an ERE in the oxytocin promoter. Methylation interference assays demonstrated that specific guanine residues required for RXR/PPAR binding to the ERE were similar to residues required for ER binding. Moreover, RXR domain-deleted constructs in transfection assays showed that activation required RXR since an RXR delta AF-2 mutant completely abrogated reporter activity. Oligoprecipitation binding studies with biotinylated ERE and (35)S-labeled in vitro translated RXR constructs confirmed binding of delta AF-2 RXR mutant to the ERE in the presence of baculovirus-expressed PPAR. Finally, in situ hybridization confirmed RXR and PPAR mRNA expression in estrogen responsive tissues. Collectively, these data suggest that RXR and PPAR are present in reproductive tissues, are capable of activating estrogen responsive genes and suggest that the mechanism of activation may involve direct binding of the receptors to estrogen response elements.

  6. Membrane estrogen receptors - is it an alternative way of estrogen action?

    PubMed

    Soltysik, K; Czekaj, P

    2013-04-01

    The functions of estrogens are relatively well known, however the molecular mechanism of their action is not clear. The classical pathway of estrogen action is dependent on ERα and ERβ which act as transcription factors. The effects of this pathway occur within hours or days. In addition, so-called, non-classical mechanism of steroid action dependent on membrane estrogen receptors (mER) was described. In this mechanism the effects of estrogen action are observed in a much shorter time. Here we review the structure and cellular localization of mER, molecular basis of non-classical mER action, physiological role of mER as well as implications of mER action for cancer biology. Finally, some concerns about the new estrogen receptor - GPER and candidates for estrogen receptors - ER-X and ERx, are briefly discussed. It seems that mER is a complex containing signal proteins (signalosome), as IGF receptor, EGF receptor, Ras protein, adaptor protein Shc, non-receptor kinase c-Src and PI-3K, what rationalizes production of second messengers. Some features of membrane receptors are almost identical if compared to nuclear receptors. Probably, membrane and nuclear estrogen receptors are not separate units, but rather the components of a complex mechanism in which they both cooperate with each other. We conclude that the image of the estrogen receptor as a simple transcription factor is a far-reaching simplification. A better understanding of the mechanisms of estrogen action will help us to design more effective drugs affecting signal pathways depending on both membrane and nuclear receptors.

  7. Estrogen receptor-independent catechol estrogen binding activity: protein binding studies in wild-type, Estrogen receptor-alpha KO, and aromatase KO mice tissues.

    PubMed

    Philips, Brian J; Ansell, Pete J; Newton, Leslie G; Harada, Nobuhiro; Honda, Shin-Ichiro; Ganjam, Venkataseshu K; Rottinghaus, George E; Welshons, Wade V; Lubahn, Dennis B

    2004-06-01

    Primary evidence for novel estrogen signaling pathways is based upon well-documented estrogenic responses not inhibited by estrogen receptor antagonists. In addition to 17beta-E2, the catechol estrogen 4-hydroxyestradiol (4OHE2) has been shown to elicit biological responses independent of classical estrogen receptors in estrogen receptor-alpha knockout (ERalphaKO) mice. Consequently, our research was designed to biochemically characterize the protein(s) that could be mediating the biological effects of catechol estrogens using enzymatically synthesized, radiolabeled 4-hydroxyestrone (4OHE1) and 4OHE2. Scatchard analyses identified a single class of high-affinity (K(d) approximately 1.6 nM), saturable cytosolic binding sites in several ERalphaKO estrogen-responsive tissues. Specific catechol estrogen binding was competitively inhibited by unlabeled catechol estrogens, but not by 17beta-E2 or the estrogen receptor antagonist ICI 182,780. Tissue distribution studies indicated significant binding differences both within and among various tissues in wild-type, ERalphaKO, and aromatase knockout female mice. Ligand metabolism experiments revealed extensive metabolism of labeled catechol estrogen, suggesting that catechol estrogen metabolites were responsible for the specific binding. Collectively, our data provide compelling evidence for the interaction of catechol estrogen metabolites with a novel binding protein that exhibits high affinity, specificity, and selective tissue distribution. The extensive biochemical characterization of this binding protein indicates that this protein may be a receptor, and thus may mediate ERalpha/beta-independent effects of catechol estrogens and their metabolites.

  8. Estrogen-related receptor alpha is critical for the growth of estrogen receptor-negative breast cancer

    PubMed Central

    Stein, Rebecca A.; Chang, Ching-yi; Kazmin, Dmitri A.; Way, James; Schroeder, Thies; Wergin, Melanie; Dewhirst, Mark W.; McDonnell, Donald P.

    2009-01-01

    Expression of estrogen-related receptor alpha (ERRα) has recently been shown to carry negative prognostic significance in breast and ovarian cancers. The specific role of this orphan nuclear receptor in tumor growth and progression, however, is yet to be fully understood. The significant homology between estrogen receptor alpha (ERα) and ERRα initially suggested that these receptors may have similar transcriptional targets. Using the well-characterized ERα-positive MCF-7 breast cancer cell line, we sought to gain a genome-wide picture of ERα-ERRα cross-talk using an unbiased microarray approach. In addition to generating a host of novel ERRα target genes, this study yielded the surprising result that most ERRα-regulated genes are unrelated to estrogen-signaling. The relatively small number of genes regulated by both ERα and ERRα led us to expand our study to the more aggressive and less clinically treatable ERα-negative class of breast cancers. In this setting we found that ERRα expression is required for the basal level of expression of many known and novel ERRα target genes. Introduction of an siRNA directed to ERRα into the highly aggressive breast carcinoma MDA-MB-231 cell line dramatically reduced the migratory potential of these cells. Although stable knockdown of ERRα expression in MDA-MB-231 cells had no impact on in vitro cell proliferation, a significant reduction of tumor growth rate was observed when these cells were implanted as xenografts. Our results confirm a role for ERRα in breast cancer growth and highlight it as a potential therapeutic target for estrogen receptor-negative breast cancer. PMID:18974123

  9. Importance of Extranuclear Estrogen Receptor-α and Membrane G Protein–Coupled Estrogen Receptor in Pancreatic Islet Survival

    PubMed Central

    Liu, Suhuan; Le May, Cedric; Wong, Winifred P.S.; Ward, Robert D.; Clegg, Deborah J.; Marcelli, Marco; Korach, Kenneth S.; Mauvais-Jarvis, Franck

    2009-01-01

    OBJECTIVE We showed that 17β-estradiol (E2) favors pancreatic β-cell survival via the estrogen receptor-α (ERα) in mice. E2 activates nuclear estrogen receptors via an estrogen response element (ERE). E2 also activates nongenomic signals via an extranuclear form of ERα and the G protein–coupled estrogen receptor (GPER). We studied the contribution of estrogen receptors to islet survival. RESEARCH DESIGN AND METHODS We used mice and islets deficient in estrogen receptor-α (αERKO−/−), estrogen receptor-β (βERKO−/−), estrogen receptor-α and estrogen receptor-β (αβERKO−/−), and GPER (GPERKO−/−); a mouse lacking ERα binding to the ERE; and human islets. These mice and islets were studied in combination with receptor-specific pharmacological probes. RESULTS We show that ERα protection of islet survival is ERE independent and that E2 favors islet survival through extranuclear and membrane estrogen receptor signaling. We show that ERβ plays a minor cytoprotective role compared to ERα. Accordingly, βERKO−/− mice are mildly predisposed to streptozotocin-induced islet apoptosis. However, combined elimination of ERα and ERβ in mice does not synergize to provoke islet apoptosis. In αβERKO−/− mice and their islets, E2 partially prevents apoptosis suggesting that an alternative pathway compensates for ERα/ERβ deficiency. We find that E2 protection of islet survival is reproduced by a membrane-impermeant E2 formulation and a selective GPER agonist. Accordingly, GPERKO−/− mice are susceptible to streptozotocin-induced insulin deficiency. CONCLUSIONS E2 protects β-cell survival through ERα and ERβ via ERE-independent, extra-nuclear mechanisms, as well as GPER-dependent mechanisms. The present study adds a novel dimension to estrogen biology in β-cells and identifies GPER as a target to protect islet survival. PMID:19587358

  10. Importance of extranuclear estrogen receptor-alpha and membrane G protein-coupled estrogen receptor in pancreatic islet survival.

    PubMed

    Liu, Suhuan; Le May, Cedric; Wong, Winifred P S; Ward, Robert D; Clegg, Deborah J; Marcelli, Marco; Korach, Kenneth S; Mauvais-Jarvis, Franck

    2009-10-01

    We showed that 17beta-estradiol (E(2)) favors pancreatic beta-cell survival via the estrogen receptor-alpha (ERalpha) in mice. E(2) activates nuclear estrogen receptors via an estrogen response element (ERE). E(2) also activates nongenomic signals via an extranuclear form of ERalpha and the G protein-coupled estrogen receptor (GPER). We studied the contribution of estrogen receptors to islet survival. We used mice and islets deficient in estrogen receptor-alpha (alphaERKO(-/-)), estrogen receptor-beta (betaERKO(-/-)), estrogen receptor-alpha and estrogen receptor-beta (alphabetaERKO(-/-)), and GPER (GPERKO(-/-)); a mouse lacking ERalpha binding to the ERE; and human islets. These mice and islets were studied in combination with receptor-specific pharmacological probes. We show that ERalpha protection of islet survival is ERE independent and that E(2) favors islet survival through extranuclear and membrane estrogen receptor signaling. We show that ERbeta plays a minor cytoprotective role compared to ERalpha. Accordingly, betaERKO(-/-) mice are mildly predisposed to streptozotocin-induced islet apoptosis. However, combined elimination of ERalpha and ERbeta in mice does not synergize to provoke islet apoptosis. In alphabetaERKO(-/-) mice and their islets, E(2) partially prevents apoptosis suggesting that an alternative pathway compensates for ERalpha/ERbeta deficiency. We find that E(2) protection of islet survival is reproduced by a membrane-impermeant E(2) formulation and a selective GPER agonist. Accordingly, GPERKO(-/-) mice are susceptible to streptozotocin-induced insulin deficiency. E(2) protects beta-cell survival through ERalpha and ERbeta via ERE-independent, extra-nuclear mechanisms, as well as GPER-dependent mechanisms. The present study adds a novel dimension to estrogen biology in beta-cells and identifies GPER as a target to protect islet survival.

  11. Molecular imaging provides novel insights on estrogen receptor activity in mouse brain.

    PubMed

    Stell, Alessia; Belcredito, Silvia; Ciana, Paolo; Maggi, Adriana

    2008-01-01

    Estrogen receptors have long been known to be expressed in several brain areas in addition to those directly involved in the control of reproductive functions. Investigations in humans and in animal models suggest a strong influence of estrogens on limbic and motor functions, yet the complexity and heterogeneity of neural tissue have limited our approaches to the full understanding of estrogen activity in the central nervous system. The aim of this study was to examine the transcriptional activity of estrogen receptors in the brain of male and female mice. Exploiting the ERE-Luc reporter mouse, we set up a novel, bioluminescence-based technique to study brain estrogen receptor transcriptional activity. Here we show, for the first time, that estrogen receptors are similarly active in male and female brains and that the estrous cycle affects estrogen receptor activity in regions of the central nervous system not known to be associated with reproductive functions. Because of its reproducibility and sensitivity, this novel bioluminescence application stands as a candidate as an innovative methodology for the study and development of drugs targeting brain estrogen receptors.

  12. Molecular Imaging Provides Novel Insights on Estrogen Receptor Activity in Mouse Brain

    PubMed Central

    Stell, Alessia; Belcredito, Silvia; Ciana, Paolo; Maggi, Adriana

    2009-01-01

    Estrogen receptors have long been known to be expressed in several brain areas in addition to those directly involved in the control of reproductive functions. Investigations in humans and in animal models suggest a strong influence of estrogens on limbic and motor functions, yet the complexity and heterogeneity of neural tissue have limited our approaches to the full understanding of estrogen activity in the central nervous system. The aim of this study was to examine the transcriptional activity of estrogen receptors in the brain of male and female mice. Exploiting the ERE-Luc reporter mouse, we set up a novel, bioluminescence-based technique to study brain estrogen receptor transcriptional activity. Here we show, for the first time, that estrogen receptors are similarly active in male and female brains and that the estrous cycle affects estrogen receptor activity in regions of the central nervous system not known to be associated with reproductive functions. Because of its reproducibility and sensitivity, this novel bioluminescence application candidates as an innovative methodology for the study and development of drugs targeting brain estrogen receptors. PMID:19123998

  13. Estrogen anti-inflammatory activity on human monocytes is mediated through cross-talk between estrogen receptor ERα36 and GPR30/GPER1.

    PubMed

    Pelekanou, Vasiliki; Kampa, Marilena; Kiagiadaki, Foteini; Deli, Alexandra; Theodoropoulos, Panayiotis; Agrogiannis, George; Patsouris, Efstratios; Tsapis, Andreas; Castanas, Elias; Notas, George

    2016-02-01

    Estrogens are known modulators of monocyte/macrophage functions; however, the underlying mechanism has not been clearly defined. Recently, a number of estrogen receptor molecules and splice variants were identified that exert different and sometimes opposing actions. We assessed the expression of estrogen receptors and explored their role in mediating estrogenic anti-inflammatory effects on human primary monocytes. We report that the only estrogen receptors expressed are estrogen receptor-α 36-kDa splice variant and G-protein coupled receptor 30/G-protein estrogen receptor 1, in a sex-independent manner. 17-β-Estradiol inhibits the LPS-induced IL-6 inflammatory response, resulting in inhibition of NF-κB transcriptional activity. This is achieved via a direct physical interaction of ligand-activated estrogen receptor-α 36-kDa splice variant with the p65 component of NF-κB in the nucleus. G-protein coupled receptor 30/G-protein estrogen receptor 1, which also physically interacts with estrogen receptor-α 36-kDa splice variant, acts a coregulator in this process, because its inhibition blocks the effect of estrogens on IL-6 expression. However, its activation does not mimic the effect of estrogens, on neither IL-6 nor NF-κB activity. Finally, we show that the estrogen receptor profile observed in monocytes is not modified during their differentiation to macrophages or dendritic cells in vitro and is shared in vivo by macrophages present in atherosclerotic plaques. These results position estrogen receptor-α 36-kDa splice variant and G-protein coupled receptor 30 as important players and potential therapeutic targets in monocyte/macrophage-dependent inflammatory processes. © Society for Leukocyte Biology.

  14. Estrogenic Compounds, Estrogen Receptors and Vascular Cell Signaling in the Aging Blood Vessels

    PubMed Central

    Smiley, Dia A.; Khalil, Raouf A.

    2010-01-01

    The cardiovascular benefits of menopausal hormone therapy (MHT) remain controversial. The earlier clinical observations that cardiovascular disease (CVD) was less common in MHT users compared to non-users suggested cardiovascular benefits of MHT. Also, experimental studies have identified estrogen receptors ERα, ERβ and GPR30, which mediate genomic or non-genomic effects in vascular endothelium, smooth muscle, and extracellular matrix (ECM). However, data from randomized clinical trials (RCTs), most notably the Women's Health Initiative (WHI) study, have challenged the cardiovascular benefits and highlighted adverse cardiovascular events with MHT. The discrepancies have been attributed to the design of RCTs, the subjects' advanced age and preexisting CVD, and the form of estrogen used. The discrepancies may also stem from age-related changes in vascular ER amount, distribution, integrity, and post-receptor signaling pathways as well as structural changes in the vasculature. Age-related changes in other sex hormones such as testosterone may also alter the hormonal environment and influence the cardiovascular effects of estrogen. Investigating the chemical properties, structure-activity relationship and pharmacology of natural and synthetic estrogens should improve the effectiveness of conventional MHT. Further characterization of phytoestrogens, selective estrogen-receptor modulators (SERMs), and specific ER agonists may provide substitutes to conventional MHT. Conditions with excess or low estrogen levels such as polycystic ovary syndrome (PCOS) and Turner syndrome may provide insight into the development and regulation of ER and the mechanisms of aberrant estrogen-ER interactions. The lessons learned from previous RCTs have led to more directed studies such as the Kronos Early Estrogen Prevention Study (KEEPS). Careful design of experimental models and RCTs, coupled with the development of specific ER modulators, hold the promise of improving the actions of

  15. Signaling cross-talk between peroxisome proliferator-activated receptor/retinoid X receptor and estrogen receptor through estrogen response elements.

    PubMed

    Keller, H; Givel, F; Perroud, M; Wahli, W

    1995-07-01

    Peroxisome proliferator-activated receptors (PPARs) and retinoid X receptors (RXRs) are nuclear hormone receptors that are activated by fatty acids and 9-cis-retinoic acid, respectively. PPARs and RXRs form heterodimers that activate transcription by binding to PPAR response elements (PPREs) in the promoter of target genes. The PPREs described thus far consist of a direct tandem repeat of the AGGTCA core element with one intervening nucleotide. We show here that the vitellogenin A2 estrogen response element (ERE) can also function as a PPRE and is bound by a PPAR/RXR heterodimer. Although this heterodimer can bind to several other ERE-related palindromic response elements containing AGGTCA half-sites, only the ERE is able to confer transactivation of test reporter plasmids, when the ERE is placed either close to or at a distance from the transcription initiation site. Examination of natural ERE-containing promoters, including the pS2, very-low-density apolipoprotein II and vitellogenin A2 genes, revealed considerable differences in the binding of PPAR/RXR heterodimers to these EREs. In their natural promoter context, these EREs did not allow transcriptional activation by PPARs/RXRs. Analysis of this lack of stimulation of the vitellogenin A2 promoter demonstrated that PPARs/RXRs bind to the ERE but cannot transactivate due to a nonpermissive promoter structure. As a consequence, PPARs/RXRs inhibit transactivation by the estrogen receptor through competition for ERE binding. This is the first example of signaling cross-talk between PPAR/RXR and estrogen receptor.

  16. Transcriptional targets shared by estrogen receptor- related receptors (ERRs) and estrogen receptor (ER) alpha, but not by ERbeta.

    PubMed Central

    Vanacker, J M; Pettersson, K; Gustafsson, J A; Laudet, V

    1999-01-01

    The physiological activities of estrogens are thought to be mediated by specific nuclear receptors, ERalpha and ERbeta. However, certain tissues, such as the bone, that are highly responsive to estrogens only express a low level of these receptors. Starting from this apparent contradiction, we have evaluated the potentials of two related receptors ERRalpha and ERRbeta to intervene in estrogen signaling. ERalpha, ERRalpha and ERRbeta bind to and activate transcription through both the classical estrogen response element (ERE) and the SF-1 response element (SFRE). In contrast, ERbeta DNA-binding and transcriptional activity is restricted to the ERE. Accordingly, the osteopontin gene promoter is stimulated through SFRE sequences, by ERRalpha as well as by ERalpha, but not by ERbeta. Analysis of the cross-talk within the ER/ERR subgroup of nuclear receptors thus revealed common targets but also functional differences between the two ERs. PMID:10428965

  17. The Estrogen Receptors: An Overview from Different Perspectives.

    PubMed

    Eyster, Kathleen M

    2016-01-01

    The estrogen receptors, ERα, ERβ, and GPER, mediate the effects of estrogenic compounds on their target tissues. Estrogen receptors are located in the tissues of the female reproductive tract and breast as one would expect, but also in tissues as diverse as bone, brain, liver, colon, skin, and salivary gland. The purpose of this discussion of the estrogen receptors is to provide a brief overview of the estrogen receptors and estrogen action from perspectives such as the historical, physiological, pharmacological, pathological, structural, and ligand perspectives.

  18. Estrogen receptor α dependent regulation of estrogen related receptor β and its role in cell cycle in breast cancer.

    PubMed

    Madhu Krishna, B; Chaudhary, Sanjib; Mishra, Dipti Ranjan; Naik, Sanoj K; Suklabaidya, S; Adhya, A K; Mishra, Sandip K

    2018-05-30

    Breast cancer (BC) is highly heterogeneous with ~ 60-70% of estrogen receptor positive BC patient's response to anti-hormone therapy. Estrogen receptors (ERs) play an important role in breast cancer progression and treatment. Estrogen related receptors (ERRs) are a group of nuclear receptors which belong to orphan nuclear receptors, which have sequence homology with ERs and share target genes. Here, we investigated the possible role and clinicopathological importance of ERRβ in breast cancer. Estrogen related receptor β (ERRβ) expression was examined using tissue microarray slides (TMA) of Breast Carcinoma patients with adjacent normal by immunohistochemistry and in breast cancer cell lines. In order to investigate whether ERRβ is a direct target of ERα, we investigated the expression of ERRβ in short hairpin ribonucleic acid knockdown of ERα breast cancer cells by western blot, qRT-PCR and RT-PCR. We further confirmed the binding of ERα by electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP), Re-ChIP and luciferase assays. Fluorescence-activated cell sorting analysis (FACS) was performed to elucidate the role of ERRβ in cell cycle regulation. A Kaplan-Meier Survival analysis of GEO dataset was performed to correlate the expression of ERRβ with survival in breast cancer patients. Tissue microarray (TMA) analysis showed that ERRβ is significantly down-regulated in breast carcinoma tissue samples compared to adjacent normal. ER + ve breast tumors and cell lines showed a significant expression of ERRβ compared to ER-ve tumors and cell lines. Estrogen treatment significantly induced the expression of ERRβ and it was ERα dependent. Mechanistic analyses indicate that ERα directly targets ERRβ through estrogen response element and ERRβ also mediates cell cycle regulation through p18, p21 cip and cyclin D1 in breast cancer cells. Our results also showed the up-regulation of ERRβ promoter activity in ectopically co

  19. Hormone Binding to Recombinant Estrogen Receptors from Human, Alligator, Quail, Salamander, and Fathead Minnow

    EPA Science Inventory

    In this work, a 96-well plate estrogen receptor binding assay was developed to facilitate the direct comparison of chemical binding to full-length recombinant estrogen receptors across vertebrate classes. Receptors were generated in a baculovirus expression system. This approach ...

  20. A-C Estrogens as Potent and Selective Estrogen Receptor-Beta Agonists (SERBAs) to Enhance Memory Consolidation under Low-Estrogen Conditions.

    PubMed

    Hanson, Alicia M; Perera, K L Iresha Sampathi; Kim, Jaekyoon; Pandey, Rajesh K; Sweeney, Noreena; Lu, Xingyun; Imhoff, Andrea; Mackinnon, Alexander Craig; Wargolet, Adam J; Van Hart, Rochelle M; Frick, Karyn M; Donaldson, William A; Sem, Daniel S

    2018-06-14

    Estrogen receptor-beta (ERβ) is a drug target for memory consolidation in postmenopausal women. Herein is reported a series of potent and selective ERβ agonists (SERBAs) with in vivo efficacy that are A-C estrogens, lacking the B and D estrogen rings. The most potent and selective A-C estrogen is selective for activating ER relative to seven other nuclear hormone receptors, with a surprising 750-fold selectivity for the β over α isoform and with EC 50 s of 20-30 nM in cell-based and direct binding assays. Comparison of potency in different assays suggests that the ER isoform selectivity is related to the compound's ability to drive the productive conformational change needed to activate transcription. The compound also shows in vivo efficacy after microinfusion into the dorsal hippocampus and after intraperitoneal injection (0.5 mg/kg) or oral gavage (0.5 mg/kg). This simple yet novel A-C estrogen is selective, brain penetrant, and facilitates memory consolidation.

  1. Estrogen promotes megakaryocyte polyploidization via estrogen receptor beta-mediated transcription of GATA1.

    PubMed

    Du, C; Xu, Y; Yang, K; Chen, S; Wang, X; Wang, S; Wang, C; Shen, M; Chen, F; Chen, M; Zeng, D; Li, F; Wang, T; Wang, F; Zhao, J; Ai, G; Cheng, T; Su, Y; Wang, J

    2017-04-01

    Estrogen is reported to be involved in thrombopoiesis and the disruption of its signaling may cause myeloproliferative disease, yet the underlying mechanisms remain largely unknown. GATA-binding factor 1 (GATA1) is a key regulator of megakaryocyte (MK) differentiation and its deficiency will lead to megakaryoblastic leukemia. Here we show that estrogen can dose-dependently promote MK polyploidization and maturation via activation of estrogen receptor beta (ERβ), accompanied by a significant upregulation of GATA1. Chromatin immunoprecipitation and a dual luciferase assay demonstrate that ERβ can directly bind the promoter region of GATA1 and activate its transcription. Steroid receptor coactivator 3 (SRC3) is involved in ERβ-mediated GATA1 transcription. The deficiency of ERβ or SRC3, similar to the inhibition of GATA1, leads to the impediment of estrogen-induced MK polyploidization and platelet production. Further investigations reveal that signal transducer and activator of transcription 1 signaling pathway downstream of GATA1 has a crucial role in estrogen-induced MK polyploidization, and ERβ-mediated GATA1 upregulation subsequently enhances nuclear factor erythroid-derived 2 expression, thereby promoting proplatelet formation and platelet release. Our study provides a deep insight into the molecular mechanisms of estrogen signaling in regulating thrombopoiesis and the pathogenesis of ER deficiency-related leukemia.

  2. Estrogen Receptors Modulation of Anxiety-Like Behavior.

    PubMed

    Borrow, A P; Handa, R J

    2017-01-01

    Estrogens exert profound effects on the expression of anxiety in humans and rodents; however, the directionality of these effects varies considerably within both clinical and preclinical literature. It is believed that discrepancies regarding the nature of estrogens' effects on anxiety are attributable to the differential effects of specific estrogen receptor (ER) subtypes. In this chapter we will discuss the relative impact on anxiety and anxiety-like behavior of each of the three main ERs: ERα, which has a generally anxiogenic effect, ERβ, which has a generally anxiolytic effect, and the G-protein-coupled ER known as GPR30, which has been found to both increase and decrease anxiety-like behavior. In addition, we will describe the known mechanisms by which these receptor subtypes exert their influence on emotional responses, focusing on the hypothalamic-pituitary-adrenal axis and the oxytocinergic and serotonergic systems. The impact of estrogens on the expression of anxiety is likely the result of their combined effects on all of these neurobiological systems. © 2017 Elsevier Inc. All rights reserved.

  3. Estrogen receptor status of breast cancer in Ontario

    PubMed Central

    McKeown-Eyssen, Gail E.; Rogers-Melamed, Iris; Clarke, E. Aileen

    1985-01-01

    Data from a number of studies of breast cancer have suggested that after the ages associated with the menopause the rates of estrogen-receptor-positive tumours increase with age, whereas the rates of estrogen-receptor-negative tumours do not. Previous investigators studied cases in specific treatment centres, so there was a possibility that the findings were influenced by differences in patterns of case referral by age. A review of all the cases of breast cancer diagnosed in Ontario women in 1981 and assayed for estrogen receptors, however, confirmed the earlier findings. The results showed that the incidence of estrogen-receptor-positive and estrogen-receptor-negative tumours increased at about the same rate before age 45, but thereafter an increase in incidence was seen only for estrogen-receptor-positive tumours. These differences in patterns of incidence suggest the possibility that the two types of tumour may have different etiologic factors. PMID:4063915

  4. Development of a Competitive Binding Assay System with Recombinant Estrogen Receptors from Multiple Species

    EPA Science Inventory

    ABSTRACT In the current study, we developed a new system using full-length recombinant baculovirus-expressed estrogen receptors which allows for direct comparison of binding across species. Estrogen receptors representing five vertebrate classes were compared: human (hERα), quai...

  5. Estrogen Receptors Modulation of Anxiety-Like Behavior

    PubMed Central

    Borrow, A.P.; Handa, R.J.

    2018-01-01

    Estrogens exert profound effects on the expression of anxiety in humans and rodents; however, the directionality of these effects varies considerably within both clinical and preclinical literature. It is believed that discrepancies regarding the nature of estrogens’ effects on anxiety are attributable to the differential effects of specific estrogen receptor (ER) subtypes. In this chapter we will discuss the relative impact on anxiety and anxiety-like behavior of each of the three main ERs: ERα, which has a generally anxiogenic effect, ERβ, which has a generally anxiolytic effect, and the G-protein-coupled ER known as GPR30, which has been found to both increase and decrease anxiety-like behavior. In addition, we will describe the known mechanisms by which these receptor subtypes exert their influence on emotional responses, focusing on the hypothalamic–pituitary–adrenal axis and the oxytocinergic and serotonergic systems. The impact of estrogens on the expression of anxiety is likely the result of their combined effects on all of these neurobiological systems. PMID:28061972

  6. Estrogen directly and specifically downregulates NaPi-IIa through the activation of both estrogen receptor isoforms (ERα and ERβ) in rat kidney proximal tubule.

    PubMed

    Burris, Dara; Webster, Rose; Sheriff, Sulaiman; Faroqui, Rashma; Levi, Moshe; Hawse, John R; Amlal, Hassane

    2015-03-15

    We have previously demonstrated that estrogen (E2) downregulates phosphate transporter NaPi-IIa and causes phosphaturia and hypophosphatemia in ovariectomized rats. In the present study, we examined whether E2 directly targets NaPi-IIa in the proximal tubule (PT) and studied the respective roles of estrogen receptor isoforms (ERα and ERβ) in the downregulation of NaPi-IIa using both in vivo and an in vitro expression systems. We found that estrogen specifically downregulates NaPi-IIa but not NaPi-IIc or Pit2 in the kidney cortex. Proximal tubules incubated in a "shake" suspension with E2 for 24 h exhibited a dose-dependent decrease in NaPi-IIa protein abundance. Results from OVX rats treated with specific agonists for either ERα [4,4',4″;-(4-propyl-[1H]-pyrazole-1,3,5-triyl) trisphenol, PPT] or ERβ [4,4',4″-(4-propyl-[1H]-pyrazole-1,3,5-triyl) trisphenol, DPN] or both (PPT + DPN), indicated that only the latter caused a sharp downregulation of NaPi-IIa, along with significant phosphaturia and hypophosphatemia. Lastly, heterologous expression studies demonstrated that estrogen downregulated NaPi-IIa only in U20S cells expressing both ERα and ERβ, but not in cells expressing either receptor alone. In conclusion, these studies demonstrate that rat PT cells express both ERα and ERβ and that E2 induces phosphaturia by directly and specifically targeting NaPi-IIa in the PT cells. This effect is mediated via a mechanism involving coactivation of both ERα and ERβ, which likely form a functional heterodimer complex in the rat kidney proximal tubule. Copyright © 2015 the American Physiological Society.

  7. Estrogen directly and specifically downregulates NaPi-IIa through the activation of both estrogen receptor isoforms (ERα and ERβ) in rat kidney proximal tubule

    PubMed Central

    Burris, Dara; Webster, Rose; Sheriff, Sulaiman; Faroqui, Rashma; Levi, Moshe; Hawse, John R.

    2015-01-01

    We have previously demonstrated that estrogen (E2) downregulates phosphate transporter NaPi-IIa and causes phosphaturia and hypophosphatemia in ovariectomized rats. In the present study, we examined whether E2 directly targets NaPi-IIa in the proximal tubule (PT) and studied the respective roles of estrogen receptor isoforms (ERα and ERβ) in the downregulation of NaPi-IIa using both in vivo and an in vitro expression systems. We found that estrogen specifically downregulates NaPi-IIa but not NaPi-IIc or Pit2 in the kidney cortex. Proximal tubules incubated in a “shake” suspension with E2 for 24 h exhibited a dose-dependent decrease in NaPi-IIa protein abundance. Results from OVX rats treated with specific agonists for either ERα [4,4′,4″;-(4-propyl-[1H]-pyrazole-1,3,5-triyl) trisphenol, PPT] or ERβ [4,4′,4″-(4-propyl-[1H]-pyrazole-1,3,5-triyl) trisphenol, DPN] or both (PPT + DPN), indicated that only the latter caused a sharp downregulation of NaPi-IIa, along with significant phosphaturia and hypophosphatemia. Lastly, heterologous expression studies demonstrated that estrogen downregulated NaPi-IIa only in U20S cells expressing both ERα and ERβ, but not in cells expressing either receptor alone. In conclusion, these studies demonstrate that rat PT cells express both ERα and ERβ and that E2 induces phosphaturia by directly and specifically targeting NaPi-IIa in the PT cells. This effect is mediated via a mechanism involving coactivation of both ERα and ERβ, which likely form a functional heterodimer complex in the rat kidney proximal tubule. PMID:25608964

  8. Estrogen Receptors Alpha and Beta in Bone

    PubMed Central

    Khalid, Aysha B.; Krum, Susan A.

    2016-01-01

    Estrogens are important for bone metabolism via a variety of mechanisms in osteoblasts, osteocytes, osteoclasts, immune cells and other cells to maintain bone mineral density. Estrogens bind to estrogen receptor alpha (ERα) and ERβ, and the roles of each of these receptors are beginning to be elucidated through whole body and tissue-specific knockouts of the receptors. In vitro and in vivo experiments have shown that ERα and ERβ antagonize each other in bone and in other tissues. This review will highlight the role of these receptors in bone, with particular emphasis on their antagonism. PMID:27072516

  9. Estrogen receptors in neuropeptide Y neurons: at the crossroads of feeding and reproduction.

    PubMed

    Acosta-Martinez, Maricedes; Horton, Teresa; Levine, Jon E

    2007-03-01

    Hypothalamic neuropeptide Y (NPY) neurons function as physiological integrators in at least two different neuroendocrine systems - one governing feeding and the other controlling reproduction. Estrogen might modulate both systems by regulating NPY gene expression; it might reduce food intake by suppressing NPY expression, and evoke reproductive hormone surges by stimulating it. How can estrogen exert opposing effects in an ostensibly homogeneous NPY neuronal population? Recent work with immortalized NPY-producing cells suggests that the ratio of estrogen receptor alpha:estrogen receptor beta can determine the direction and temporal pattern of transcriptional responses to estrogen. Because this ratio might itself be physiologically regulated, these findings provide one explanation for multiple neuropeptidergic responses to a single steroid hormone.

  10. GPR30: A G protein-coupled receptor for estrogen.

    PubMed

    Prossnitz, Eric R; Arterburn, Jeffrey B; Sklar, Larry A

    2007-02-01

    Estrogen is a critical steroid in human physiology exerting its effect both at the transcriptional level as well as at the level of rapid intracellular signaling through second messengers. Many of estrogen's transcriptional effects have long been known to be mediated through classical nuclear steroid receptors but recent studies also demonstrate the existence of a 7-transmembrane G protein-coupled receptor, GPR30 that responds to estrogen with rapid cellular signaling. There is currently controversy over the ability of classical estrogen receptors to recapitulate GPR30-mediated signaling mechanisms and vice versa. This article will summarize recent literature and address the relationship between GPR30 and conventional estrogen receptor signaling.

  11. The anticancer estrogen receptor antagonist tamoxifen impairs consolidation of inhibitory avoidance memory through estrogen receptor alpha.

    PubMed

    Lichtenfels, Martina; Dornelles, Arethuza da Silva; Petry, Fernanda Dos Santos; Blank, Martina; de Farias, Caroline Brunetto; Roesler, Rafael; Schwartsmann, Gilberto

    2017-11-01

    Over two-thirds of women with breast cancer have positive tumors for hormone receptors, and these patients undergo treatment with endocrine therapy, tamoxifen being the most widely used agent. Despite being very effective in breast cancer treatment, tamoxifen is associated with side effects that include cognitive impairments. However, the specific aspects and mechanisms underlying these impairments remain to be characterized. Here, we have investigated the effects of tamoxifen and interaction with estrogen receptors on formation of memory for inhibitory avoidance conditioning in female rats. In the first experiment, Wistar female rats received a single oral dose of tamoxifen (1, 3, or 10 mg/kg) or saline by gavage immediately after training and were tested for memory consolidation 24 h after training. In the second experiment, rats received a single dose of 1 mg/kg tamoxifen or saline by gavage 3 h after training and were tested 24 h after training for memory consolidation. In the third experiment, rats received a subcutaneous injection with estrogen receptor α agonist or estrogen receptor beta agonist 30 min before the training. After training, rats received a single oral dose of tamoxifen 1 mg/kg or saline and were tested 24 h after training. In the fourth experiment, rats were trained and tested 24 h later. Immediately after test, rats received a single dose of tamoxifen (1 mg/kg) or saline by gavage and were given four additional daily test trials followed by a re-instatement. Tamoxifen at 1 mg/kg impaired memory consolidation when given immediately after training and the estrogen receptor alpha agonist improved the tamoxifen-related memory impairment. Moreover, tamoxifen impairs memory consolidation of the test. These findings indicate that estrogen receptors regulate the early phase of memory consolidation and the effects of tamoxifen on memory consolidation.

  12. Estrogen receptor beta in prostate cancer: friend or foe?

    PubMed

    Nelson, Adam W; Tilley, Wayne D; Neal, David E; Carroll, Jason S

    2014-08-01

    Prostate cancer is the commonest, non-cutaneous cancer in men. At present, there is no cure for the advanced, castration-resistant form of the disease. Estrogen has been shown to be important in prostate carcinogenesis, with evidence resulting from epidemiological, cancer cell line, human tissue and animal studies. The prostate expresses both estrogen receptor alpha (ERA) and estrogen receptor beta (ERB). Most evidence suggests that ERA mediates the harmful effects of estrogen in the prostate, whereas ERB is tumour suppressive, but trials of ERB-selective agents have not translated into improved clinical outcomes. The role of ERB in the prostate remains unclear and there is increasing evidence that isoforms of ERB may be oncogenic. Detailed study of ERB and ERB isoforms in the prostate is required to establish their cell-specific roles, in order to determine if therapies can be directed towards ERB-dependent pathways. In this review, we summarise evidence on the role of ERB in prostate cancer and highlight areas for future research. © 2014 Society for Endocrinology.

  13. Estrogen-mediated inactivation of FOXO3a by the G protein-coupled estrogen receptor GPER.

    PubMed

    Zekas, Erin; Prossnitz, Eric R

    2015-10-15

    Estrogen (17β-estradiol) promotes the survival and proliferation of breast cancer cells and its receptors represent important therapeutic targets. The cellular actions of estrogen are mediated by the nuclear estrogen receptors ERα and ERβ as well as the 7-transmembrane spanning G protein-coupled estrogen receptor (GPER). We previously reported that estrogen activates the phosphoinositide 3-kinase (PI3Kinase) pathway via GPER, resulting in phosphatidylinositol (3,4,5)-trisphosphate (PIP3) production within the nucleus of breast cancer cells; however, the mechanisms and consequences of this activity remained unclear. MCF7 breast cancer cells were transfected with GFP-fused Forkhead box O3 (FOXO3) as a reporter to assess localization in response to estrogen stimulation. Inhibitors of PI3Kinases and EGFR were employed to determine the mechanisms of estrogen-mediated FOXO3a inactivation. Receptor knockdown with siRNA and the selective GPER agonist G-1 elucidated the estrogen receptor(s) responsible for estrogen-mediated FOXO3a inactivation. The effects of selective estrogen receptor modulators and downregulators (SERMs and SERDs) on FOXO3a in MCF7 cells were also determined. Cell survival (inhibition of apoptosis) was assessed by caspase activation. In the estrogen-responsive breast cancer cell line MCF7, FOXO3a inactivation occurs on a rapid time scale as a result of GPER, but not ERα, stimulation by estrogen, established by the GPER-selective agonist G-1 and knockdown of GPER and ERα. GPER-mediated inactivation of FOXO3a is effected by the p110α catalytic subunit of PI3Kinase as a result of transactivation of the EGFR. The SERMs tamoxifen and raloxifene, as well as the SERD ICI182,780, were active in mediating FOXO3a inactivation in a GPER-dependent manner. Additionally, estrogen-and G-1-mediated stimulation of MCF7 cells results in a decrease in caspase activation under proapoptotic conditions. Our results suggest that non-genomic signaling by GPER contributes

  14. Progesterone receptor modulates estrogen receptor-α action in breast cancer

    PubMed Central

    Mohammed, Hisham; Russell, I. Alasdair; Stark, Rory; Rueda, Oscar M.; Hickey, Theresa E.; Tarulli, Gerard A.; Serandour, Aurelien A. A.; Birrell, Stephen N.; Bruna, Alejandra; Saadi, Amel; Menon, Suraj; Hadfield, James; Pugh, Michelle; Raj, Ganesh V.; Brown, Gordon D.; D’Santos, Clive; Robinson, Jessica L. L.; Silva, Grace; Launchbury, Rosalind; Perou, Charles M.; Stingl, John; Caldas, Carlos; Tilley, Wayne D.; Carroll, Jason S.

    2015-01-01

    Summary Progesterone receptor (PR) expression is employed as a biomarker of estrogen receptor-α (ERα) function and breast cancer prognosis. We now show that PR is not merely an ERα-induced gene target, but is also an ERα-associated protein that modulates its behaviour. In the presence of agonist ligands, PR associates with ERα to direct ERα chromatin binding events within breast cancer cells, resulting in a unique gene expression programme that is associated with good clinical outcome. Progesterone inhibited estrogen-mediated growth of ERα+ cell line xenografts and primary ERα+ breast tumour explants and had increased anti-proliferative effects when coupled with an ERα antagonist. Copy number loss of PgR is a common feature in ERα+ breast cancers, explaining lower PR levels in a subset of cases. Our findings indicate that PR functions as a molecular rheostat to control ERα chromatin binding and transcriptional activity, which has important implications for prognosis and therapeutic interventions. PMID:26153859

  15. Sex Hormones and Cardiometabolic Health: Role of Estrogen and Estrogen Receptors.

    PubMed

    Clegg, Deborah; Hevener, Andrea L; Moreau, Kerrie L; Morselli, Eugenia; Criollo, Alfredo; Van Pelt, Rachael E; Vieira-Potter, Victoria J

    2017-05-01

    With increased life expectancy, women will spend over three decades of life postmenopause. The menopausal transition increases susceptibility to metabolic diseases such as obesity, diabetes, cardiovascular disease, and cancer. Thus, it is more important than ever to develop effective hormonal treatment strategies to protect aging women. Understanding the role of estrogens, and their biological actions mediated by estrogen receptors (ERs), in the regulation of cardiometabolic health is of paramount importance to discover novel targeted therapeutics. In this brief review, we provide a detailed overview of the literature, from basic science findings to human clinical trial evidence, supporting a protective role of estrogens and their receptors, specifically ERα, in maintenance of cardiometabolic health. In so doing, we provide a concise mechanistic discussion of some of the major tissue-specific roles of estrogens signaling through ERα. Taken together, evidence suggests that targeted, perhaps receptor-specific, hormonal therapies can and should be used to optimize the health of women as they transition through menopause, while reducing the undesired complications that have limited the efficacy and use of traditional hormone replacement interventions. Copyright © 2017 Endocrine Society.

  16. Expression of estrogen and progesterone receptors in astrocytomas: a literature review

    PubMed Central

    Tavares, Cléciton Braga; Gomes-Braga, Francisca das Chagas Sheyla Almeida; Costa-Silva, Danylo Rafhael; Escórcio-Dourado, Carla Solange; Borges, Umbelina Soares; Conde, Airton Mendes; da Conceição Barros-Oliveira, Maria; Sousa, Emerson Brandão; da Rocha Barros, Lorena; Martins, Luana Mota; Facina, Gil; da-Silva, Benedito Borges

    2016-01-01

    Gliomas are the most common type of primary central nervous system neoplasm. Astrocytomas are the most prevalent type of glioma and these tumors may be influenced by sex steroid hormones. A literature review for the presence of estrogen and progesterone receptors in astrocytomas was conducted in the PubMed database using the following MeSH terms: “estrogen receptor beta” OR “estrogen receptor alpha” OR “estrogen receptor antagonists” OR “progesterone receptors” OR “astrocytoma” OR “glioma” OR “glioblastoma”. Among the 111 articles identified, 13 studies met our inclusion criteria. The majority of reports showed the presence of estrogen and progesterone receptors in astrocytomas. Overall, higher tumor grades were associated with decreased estrogen receptor expression and increased progesterone receptor expression. PMID:27626480

  17. The role of estrogen and androgen receptors in bone health and disease

    PubMed Central

    2014-01-01

    Mouse models with cell-specific deletion of the estrogen receptor (ER) α, the androgen receptor (AR) or the receptor activator of nuclear factor κB ligand (RANKL), as well as cascade-selective estrogenic compounds have provided novel insights into the function and signalling of ERα and AR. The studies reveal that the effects of estrogens on trabecular versus cortical bone mass are mediated by direct effects on osteoclasts and osteoblasts, respectively. The protection of cortical bone mass by estrogens is mediated via ERα, using a non-nucleus-initiated mechanism. By contrast, the AR of mature osteoblasts is indispensable for the maintenance of trabecular bone mass in male mammals, but not required for the anabolic effects of androgens on cortical bone. Most unexpectedly, and independently of estrogens, ERα in osteoblast progenitors stimulates Wnt signalling and periosteal bone accrual in response to mechanical strain. RANKL expression in B lymphocytes, but not T lymphocytes, contributes to the loss of trabecular bone caused by estrogen deficiency. In this Review, we summarize this evidence and discuss its implications for understanding the regulation of trabecular and cortical bone mass; the integration of hormonal and mechanical signals; the relative importance of estrogens versus androgens in the male skeleton; and, finally, the pathogenesis and treatment of osteoporosis. PMID:24042328

  18. Estrogen, vascular estrogen receptor and hormone therapy in postmenopausal vascular disease.

    PubMed

    Khalil, Raouf A

    2013-12-15

    Cardiovascular disease (CVD) is less common in premenopausal women than men of the same age or postmenopausal women, suggesting vascular benefits of estrogen. Estrogen activates estrogen receptors ERα, ERβ and GPR30 in endothelium and vascular smooth muscle (VSM), which trigger downstream signaling pathways and lead to genomic and non-genomic vascular effects such as vasodilation, decreased VSM contraction and growth and reduced vascular remodeling. However, randomized clinical trials (RCTs), such as the Women's Health Initiative (WHI) and Heart and Estrogen/progestin Replacement Study (HERS), have shown little vascular benefits and even adverse events with menopausal hormone therapy (MHT), likely due to factors related to the MHT used, ER profile, and RCT design. Some MHT forms, dose, combinations or route of administration may have inadequate vascular effects. Age-related changes in ER amount, distribution, integrity and post-ER signaling could alter the vascular response to MHT. The subject's age, preexisting CVD, and hormone environment could also reduce the effects of MHT. Further evaluation of natural and synthetic estrogens, phytoestrogens, and selective estrogen-receptor modulators (SERMs), and the design of appropriate MHT combinations, dose, route and 'timing' could improve the effectiveness of conventional MHT and provide alternative therapies in the peri-menopausal period. Targeting ER using specific ER agonists, localized MHT delivery, and activation of specific post-ER signaling pathways could counter age-related changes in ER. Examination of the hormone environment and conditions associated with hormone imbalance such as polycystic ovary syndrome may reveal the causes of abnormal hormone-receptor interactions. Consideration of these factors in new RCTs such as the Kronos Early Estrogen Prevention Study (KEEPS) could enhance the vascular benefits of estrogen in postmenopausal CVD. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Estrogen, Vascular Estrogen Receptor and Hormone Therapy in Postmenopausal Vascular Disease

    PubMed Central

    Khalil, Raouf A.

    2013-01-01

    Cardiovascular disease (CVD) is less common in premenopausal women than men of the same age or postmenopausal women, suggesting vascular benefits of estrogen. Estrogen activates estrogen receptors ERα, ERβ and GPR30 in endothelium and vascular smooth muscle (VSM), which trigger downstream signaling pathways and lead to genomic and non-genomic vascular effects such as vasodilation, decreased VSM contraction and growth and reduced vascular remodeling. However, randomized clinical trials (RCTs), such as the Women’s Health Initiative (WHI) and Heart and Estrogen/progestin Replacement Study (HERS), have shown little vascular benefits and even adverse events with menopausal hormone therapy (MHT), likely due to factors related to the MHT used, ER profile, and RCT design. Some MHT forms, dose, combinations or route of administration may have inadequate vascular effects. Age-related changes in ER amount, distribution, integrity and post-ER signaling could alter the vascular response to MHT. The subject’s age, preexisting CVD, and hormone environment could also reduce the effects of MHT. Further evaluation of natural and synthetic estrogens, phytoestrogens, and selective estrogen-receptor modulators (SERMs), and the design of appropriate MHT combinations, dose, route and 'timing' could improve the effectiveness of conventional MHT and provide alternative therapies in the peri-menopausal period. Targeting ER using specific ER agonists, localized MHT delivery, and activation of specific post-ER signaling pathways could counter age-related changes in ER. Examination of the hormone environment and conditions associated with hormone imbalance such as polycystic ovary syndrome may reveal the causes of abnormal hormone-receptor interactions. Consideration of these factors in new RCTs such as the Kronos Early Estrogen Prevention Study (KEEPS) could enhance the vascular benefits of estrogen in postmenopausal CVD. PMID:24099797

  20. Estrogen receptor mRNA in mineralized tissues of rainbow trout: calcium mobilization by estrogen.

    PubMed

    Armour, K J; Lehane, D B; Pakdel, F; Valotaire, Y; Graham, R; Russell, R G; Henderson, I W

    1997-07-07

    RT-PCR was undertaken on total RNA extracts from bone and scales of the rainbow trout, Oncorhynchus mykiss. The rainbow trout estrogen receptor (ER)-specific primers used amplified a single product of expected size from each tissue which, using Southern blotting, strongly hybridized with a 32P-labelled rtER probe under stringent conditions. These data provide the first in vivo evidence of ER mRNA in bone and scale tissues of rainbow trout and suggest that the effects of estrogen observed in this study (increased bone mineral and decreased scale mineral contents, respectively) may be mediated directly through ER.

  1. Estrogen-related receptor β (ERRβ) – renaissance receptor or receptor renaissance?

    PubMed Central

    Divekar, Shailaja D.; Tiek, Deanna M.; Fernandez, Aileen; Riggins, Rebecca B.

    2016-01-01

    Estrogen-related receptors (ERRs) are founding members of the orphan nuclear receptor (ONR) subgroup of the nuclear receptor superfamily. Twenty-seven years of study have yet to identify cognate ligands for the ERRs, though they have firmly placed ERRα and ERRγ at the intersection of cellular metabolism and oncogenesis. The pace of discovery for novel functions of ERRβ, however, has until recently been somewhat slower than that of its family members. ERRβ has also been largely ignored in summaries and perspectives of the ONR literature. Here, we provide an overview of established and emerging knowledge of ERRβ in mouse, man, and other species, highlighting unique aspects of ERRβ biology that set it apart from the other two estrogen-related receptors, with a focus on the impact of alternative splicing on the structure and function of this receptor. PMID:27507929

  2. Estrogen stimulated migration and invasion of estrogen receptor-negative breast cancer cells involves an ezrin-dependent crosstalk between G protein-coupled receptor 30 and estrogen receptor beta signaling.

    PubMed

    Zhou, Kewen; Sun, Peng; Zhang, Yaxing; You, Xinchao; Li, Ping; Wang, Tinghuai

    2016-07-01

    Estrogen mediates important cellular activities in estrogen receptor negative (ER-) breast cancer cells via membrane associated G protein-coupled receptor 30 (GPR30). However, the biological role and mechanism of estrogen action on cell motility and invasion in this aggressive kind of tumors remains poorly understood. We showed here that treatment with 17β-estradiol (E2) in ER-negative cancer cells resulted in ezrin-dependent cytoskeleton rearrangement and elicited a stimulatory effect on cell migration and invasion. Mechanistically, E2 induced ezrin activation was mediated by distinct mechanisms in different cell contexts. In SK-BR-3 cells with a high GPR30/ERβ ratio, silencing of GPR30 was able to abolish E2 induced ERK1/2, AKT phosphorylation and ezrin activation, whereas in MDA-MB-231 cells with low GPR30/ERβ ratio, E2 stimulated ezrin activation was mediated by the ERβ/PI3K/AKT signaling pathway. Importantly, we showed that activation of GPR30 signaling significantly prevents ERβ activation induced ezrin phosphorylation, cell migration and invasion, indicating an antagonist effect between GPR30 and ERβ signaling in MDA-MB-231 cells. These findings highlight the important interplay between different estrogen receptors in estrogen induced cell motility and invasiveness in ER-negative breast cancer cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Estrogenic Activity of Hyperforin in MCF-7 Human Breast Cancer Cells Transfected with Estrogen Receptor.

    PubMed

    Kwon, Joseph; Oh, Kyung Seo; Cho, Se-Young; Bang, Mi Ae; Kim, Hwan Seon; Vaidya, Bipin; Kim, Duwoon

    2016-11-01

    Hyperforin, a major active compound of St. John's wort extract, affects estrogenic activity. In this study, the compound evoked estrogen response element-dependent luciferase activity and cell proliferation in MCF-7 cells. Hyperforin-induced cell proliferation was significantly inhibited by the estrogen receptor antagonist ICI 182,780. These results suggested that hyperforin had estrogenic and cell proliferation activities, which were stimulated via the estrogen receptor. Compared to 17 β -estradiol, hyperforin showed significantly lower estrogenic activity and cell proliferation. The mechanism underlying the estrogenic activity of hyperforin was unknown, therefore, in this study, for the first time, the expression and post-translational modification of proteins were determined and compared among control, 17 β -estradiol-treated, and hyperforin-treated cells using proteomic techniques. A total of 453 proteins were identified, of which 282 proteins were significantly modulated in hyperforin-treated cells compared to 17 β -estradiol-treated cells. Ingenuity pathway analysis also demonstrated that hyperforin treatment induced less cell proliferation than 17 β -estradiol by downregulating estrogen receptor 1. Protein network analysis showed that cell proliferation was regulated mainly by cyclin D1 and extracellular signal-regulated kinases. In conclusion, although, hyperforin exhibited lower estrogenic activity than 17 β -estradiol, the compound induced lower levels of cancer cell proliferation in vitro . Georg Thieme Verlag KG Stuttgart · New York.

  4. GPR30: a seven-transmembrane-spanning estrogen receptor that triggers EGF release.

    PubMed

    Filardo, Edward J; Thomas, Peter

    2005-10-01

    Heterotrimeric G proteins and seven-transmembrane-spanning (7TM) receptors are implicated in rapid estrogen signaling. The orphan 7TM receptor GPR30 is linked to estrogen-mediated activation of adenylyl cyclase, release of epidermal growth factor (EGF)-related ligands, and specific estrogen binding. GPR30 acts independently of estrogen receptors, ERalpha and ERbeta, and probably functions as a heptahelical ER. 7TM receptors elicit signals that stimulate second messengers, and convey intracellular signals via EGF receptors. Identification of GPR30 as a Gs-coupled 7TM receptor that triggers release of heparin-binding EGF establishes its role in cell signaling cascades initiated by estrogens, and explains their capacity to activate second messengers and promote EGF-like effects. Thus, estrogen can signal by the same mechanism as various other hormones, through a specific 7TM receptor.

  5. Estrogen signaling through the G protein-coupled estrogen receptor regulates granulocyte activation in fish.

    PubMed

    Cabas, Isabel; Rodenas, M Carmen; Abellán, Emilia; Meseguer, José; Mulero, Victoriano; García-Ayala, Alfonsa

    2013-11-01

    Neutrophils are major participants in innate host responses. It is well known that estrogens have an immune-modulatory role, and some evidence exists that neutrophil physiology can be altered by these molecules. Traditionally, estrogens act via classical nuclear estrogen receptors, but the identification of a G protein-coupled estrogen receptor (GPER), a membrane estrogen receptor that binds estradiol and other estrogens, has opened up the possibility of exploring additional estrogen-mediated effects. However, information on the importance of GPER for immunity, especially, in neutrophils is scant. In this study, we report that gilthead seabream (Sparus aurata L.) acidophilic granulocytes, which are the functional equivalent of mammalian neutrophils, express GPER at both mRNA and protein levels. By using a GPER selective agonist, G1, it was found that GPER activation in vitro slightly reduced the respiratory burst of acidophilic granulocytes and drastically altered the expression profile of several genes encoding major pro- and anti-inflammatory mediators. In addition, GPER signaling in vivo modulated adaptive immunity. Finally, a cAMP analog mimicked the effects of G1 in the induction of the gene coding for PG-endoperoxide synthase 2 and in the induction of CREB phosphorylation, whereas pharmacological inhibition of protein kinase A superinduced PG-endoperoxide synthase 2. Taken together, our results demonstrate for the first time, to our knowledge, that estrogens are able to modulate vertebrate granulocyte functions through a GPER/cAMP/protein kinase A/CREB signaling pathway and could establish therapeutic targets for several immune disorders in which estrogens play a prominent role.

  6. Ritonavir binds to and downregulates estrogen receptors: Molecular mechanism of promoting early atherosclerosis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xiang, Jin; Wang, Ying; Su, Ke

    Estrogenic actions are closely related to cardiovascular disease. Ritonavir (RTV), a human immunodeficiency virus (HIV) protease inhibitor, induces atherosclerosis in an estrogen-related manner. However, how RTV induce pathological phenotypes through estrogen pathway remains unclear. In this study, we found that RTV increases thickness of coronary artery walls of Sprague Dawley rats and plasma free fatty acids (FFA) levels. In addition, RTV could induce foam cell formation, downregulate both estrogen receptor α (ERα) and ERβ expression, upregulate G protein-coupled estrogen receptor (GPER) expression, and all of them could be partially blocked by 17β-estradiol (E2), suggesting RTV acts as an antagonist formore » E2. Computational modeling shows a similar interaction with ERα between RTV and 2-aryl indoles, which are highly subtype-selective ligands for ERα. We also found that RTV directly bound to ERα and selectively inhibited the nuclear localization of ERα, and residue Leu536 in the hydrophobic core of ligand binding domain (LBD) was essential for the interaction with RTV. In addition, RTV did not change the secondary structure of ERα-LBD like E2, which explained how ERα lost the capacity of nuclear translocation under the treatment of RTV. All of the evidences suggest that ritonavir acts as an antagonist for 17β-estradiol in regulating α subtype estrogen receptor function and early events of atherosclerosis. - Graphical abstract: RTV directly binds to ERα and Leu536 in the hydrophobic core of ligand binding domain is essential for the interaction. - Highlights: • RTV increases the thickness of rat coronary artery wall and foam cell formation. • RTV downregulates the expression of ERα and ERβ. • RTV inhibits ERα promoter activity. • RTV directly binds to ERα and the key amino acid is Leu536. • RTV inhibits the nuclear translocation of ERα and GPER.« less

  7. Estrogen receptor coregulator binding modulators (ERXs) effectively target estrogen receptor positive human breast cancers

    PubMed Central

    Raj, Ganesh V; Sareddy, Gangadhara Reddy; Ma, Shihong; Lee, Tae-Kyung; Viswanadhapalli, Suryavathi; Li, Rui; Liu, Xihui; Murakami, Shino; Chen, Chien-Cheng; Lee, Wan-Ru; Mann, Monica; Krishnan, Samaya Rajeshwari; Manandhar, Bikash; Gonugunta, Vijay K; Strand, Douglas; Tekmal, Rajeshwar Rao; Ahn, Jung-Mo; Vadlamudi, Ratna K

    2017-01-01

    The majority of human breast cancer is estrogen receptor alpha (ER) positive. While anti-estrogens/aromatase inhibitors are initially effective, resistance to these drugs commonly develops. Therapy-resistant tumors often retain ER signaling, via interaction with critical oncogenic coregulator proteins. To address these mechanisms of resistance, we have developed a novel ER coregulator binding modulator, ERX-11. ERX-11 interacts directly with ER and blocks the interaction between a subset of coregulators with both native and mutant forms of ER. ERX-11 effectively blocks ER-mediated oncogenic signaling and has potent anti-proliferative activity against therapy-sensitive and therapy-resistant human breast cancer cells. ERX-11 is orally bioavailable, with no overt signs of toxicity and potent activity in both murine xenograft and patient-derived breast tumor explant models. This first-in-class agent, with its novel mechanism of action of disrupting critical protein-protein interactions, overcomes the limitations of current therapies and may be clinically translatable for patients with therapy-sensitive and therapy-resistant breast cancers. DOI: http://dx.doi.org/10.7554/eLife.26857.001 PMID:28786813

  8. The Role of Hypothalamic Estrogen Receptors in Metabolic Regulation

    PubMed Central

    Frank, Aaron; Brown, Lynda M.; Clegg, Deborah J.

    2014-01-01

    Estrogens regulate key features of metabolism, including food intake, body weight, energy expenditure, insulin sensitivity, leptin sensitivity, and body fat distribution. There are two ”classical“ estrogen receptors (ERs): estrogen receptor alpha (ERS1) and estrogen receptor beta (ERS2). Human and murine data indicate ERS1 contributes to metabolic regulation more so than ESR2. For example, there are human inactivating mutations of ERS1 which recapitulate aspects of the metabolic syndrome in both men and women. Much of our understanding of the metabolic roles of ERS1 was initially uncovered in estrogen receptor α-null mice (ERS1−/−); these mice display aspects of the metabolic syndrome, including increased body weight, increased visceral fat deposition and dysregulated glucose intolerance. Recent data further implicate ERS1 in specific tissues and neuronal populations as being critical for regulating food intake, energy expenditure, body fat distribution and adipose tissue function. This review will focus predominantly on the role of hypothalamic ERs and their critical role in regulating all aspects of energy homeostasis and metabolism. PMID:24882636

  9. The role of hypothalamic estrogen receptors in metabolic regulation.

    PubMed

    Frank, Aaron; Brown, Lynda M; Clegg, Deborah J

    2014-10-01

    Estrogens regulate key features of metabolism, including food intake, body weight, energy expenditure, insulin sensitivity, leptin sensitivity, and body fat distribution. There are two 'classical' estrogen receptors (ERs): estrogen receptor alpha (ERS1) and estrogen receptor beta (ERS2). Human and murine data indicate ERS1 contributes to metabolic regulation more so than ESR2. For example, there are human inactivating mutations of ERS1 which recapitulate aspects of the metabolic syndrome in both men and women. Much of our understanding of the metabolic roles of ERS1 was initially uncovered in estrogen receptor α-null mice (ERS1(-/-)); these mice display aspects of the metabolic syndrome, including increased body weight, increased visceral fat deposition and dysregulated glucose intolerance. Recent data further implicate ERS1 in specific tissues and neuronal populations as being critical for regulating food intake, energy expenditure, body fat distribution and adipose tissue function. This review will focus predominantly on the role of hypothalamic ERs and their critical role in regulating all aspects of energy homeostasis and metabolism. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Insights from the Study of Animals Lacking Functional Estrogen Receptor

    NASA Astrophysics Data System (ADS)

    Korach, Kenneth S.

    1994-12-01

    Estrogen hormones produce physiological actions within a variety of target sites in the body and during development by activating a specific receptor protein. Hormone responsiveness for the estrogen receptor protein was investigated at different stages of development with the use of gene knockout techniques because no natural genetic mutants have been described. A mutant mouse line without a functional estrogen receptor was created and is being used to assess estrogen responsiveness. Both sexes of these mutant animals are infertile and show a variety of phenotypic changes, some of which are associated with the gonads, mammary glands, reproductive tracts, and skeletal tissues.

  11. Targeted Radiotherapy of Estrogen Receptor Positive Tumors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Raghavan Rajagopalan

    The overall objectives of the proposal were to develop estrogen receptor (ER) binding small molecule radiopharmaceuticals for targeted radiotherapy of ER positive (ER+) tumors. In particular, this proposal focused on embedding a {sup 186,188}Re or a {sup 32}P radionuclide into an estrogen steroidal framework by isosteric substitution such that the resulting structure is topologically similar to the estrogen (estrogen mimic). The estrogen mimic molecules expected to bind to the ER and exhibit biodistribution akin to that of native estrogen due to structural mimicry. It is anticipated that the {sup 186,188}Re- or a {sup 32}P-containing estrogen mimics will be useful formore » targeted molecular radiotherapy of ER+ tumors. It is well established that the in vivo target tissue uptake of estrogen like steroidal molecules is related to the binding of the steroids to sex hormone binding globulin (SHBG). SHBG is important in the uptake of estrogens and testosterone in target tissues by SHBG receptors on the cell surface. However, hitherto the design of estrogen like small molecule radiopharmaceuticals was focused on optimizing ER binding characteristics without emphasis on SHBG binding properties. Consequently, even the molecules with good ER affinity in vitro, performed poorly in biodistribution studies. Based on molecular modeling studies the proposal focused on developing estrogen mimics 1-3 which were topologically similar to native estrogens, and form hydrogen bonds in ER and SHBG in the same manner as those of native estrogens. To this end the technical objectives of the proposal focused on synthesizing the rhenium-estrone and estradiol mimics 1 and 2 respectively, and phosphorous estradiol mimic 3 and to assess their stability and in vitro binding characteristics to ER and SHBG.« less

  12. A recombinant estrogen receptor fragment-based homogeneous fluorescent assay for rapid detection of estrogens.

    PubMed

    Wang, Dan; Xie, Jiangbi; Zhu, Xiaocui; Li, Jinqiu; Zhao, Dongqin; Zhao, Meiping

    2014-05-15

    In this work, we demonstrate a novel estrogenic receptor fragment-based homogeneous fluorescent assay which enables rapid and sensitive detection of 17β-estradiol (E2) and other highly potent estrogens. A modified human estrogenic receptor fragment (N-His × 6-hER270-595-C-Strep tag II) has been constructed that contains amino acids 270-595 of wild-type human estrogenic receptor α (hER270-595) and two specific tags (6 × His and Strep tag II) fused to the N and C terminus, respectively. The designed receptor protein fragment could be easily produced by prokaryotic expression with high yield and high purity. The obtained protein exhibits high binding affinity to E2 and the two tags greatly facilitate the application of the recombinant protein. Taking advantage of the unique spectroscopic properties of coumestrol (CS), a fluorescent phytoestrogen, a CS/hER270-595-based fluorescent assay has been developed which can sensitively respond to E2 within 1.0 min with a linear working range from 0.1 to 20 ng/mL and a limit of detection of 0.1 ng/mL. The assay was successfully applied for rapid detection of E2 in the culture medium of rat hippocampal neurons. The method also holds great potential for high-throughput monitoring the variation of estrogen levels in complex biological fluids, which is crucial for investigation of the molecular basis of various estrogen-involved processes. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Lordosis facilitated by GPER-1 receptor activation involves GnRH-1, progestin and estrogen receptors in estrogen-primed rats.

    PubMed

    Domínguez-Ordóñez, R; Garcia-Juárez, M; Lima-Hernández, F J; Gómora-Arrati, P; Domínguez-Salazar, E; Blaustein, J D; Etgen, A M; González-Flores, O

    2018-02-01

    The present study assessed the participation of membrane G-protein coupled estrogen receptor 1 (GPER-1) and gonadotropin releasing hormone 1 (GnRH-1) receptor in the display of lordosis induced by intracerebroventricular (icv) administration of G1, a GPER-1 agonist, and by unesterified 17β-estradiol (free E 2 ). In addition, we assessed the participation of both estrogen and progestin receptors in the lordosis behavior induced by G1 in ovariectomized (OVX), E 2 -benzoate (EB)-primed rats. In Experiment 1, icv injection of G1 induced lordosis behavior at 120 and 240min. In Experiment 2, icv injection of the GPER-1 antagonist G15 significantly reduced lordosis behavior induced by either G1 or free E 2 . In addition, Antide, a GnRH-1 receptor antagonist, significantly depressed G1 facilitation of lordosis behavior in OVX, EB-primed rats. Similarly, icv injection of Antide blocked the stimulatory effect of E 2 on lordosis behavior. In Experiment 3, systemic injection of either tamoxifen or RU486 significantly reduced lordosis behavior induced by icv administration of G1 in OVX, EB-primed rats. The results suggest that GnRH release activates both estrogen and progestin receptors and that this activation is important in the chain of events leading to the display of lordosis behavior in response to activation of GPER-1 in estrogen-primed rats. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Extent of Vascular Remodeling Is Dependent on the Balance Between Estrogen Receptor α and G-Protein-Coupled Estrogen Receptor.

    PubMed

    Gros, Robert; Hussain, Yasin; Chorazyczewski, Jozef; Pickering, J Geoffrey; Ding, Qingming; Feldman, Ross D

    2016-11-01

    Estrogens are important regulators of cardiovascular function. Some of estrogen's cardiovascular effects are mediated by a G-protein-coupled receptor mechanism, namely, G-protein-coupled estrogen receptor (GPER). Estradiol-mediated regulation of vascular cell programmed cell death reflects the balance of the opposing actions of GPER versus estrogen receptor α (ERα). However, the significance of these opposing actions on the regulation of vascular smooth muscle cell proliferation or migration in vitro is unclear, and the significance in vivo is unknown. To determine the effects of GPER activation in vitro, we studied rat aortic vascular smooth muscle cells maintained in primary culture. GPER was reintroduced using adenoviral gene transfer. Both estradiol and G1, a GPER agonist, inhibited both proliferation and cell migration effects that were blocked by the GPER antagonist, G15. To determine the importance of the GPER-ERα balance in regulating vascular remodeling in a rat model of carotid ligation, we studied the effects of upregulation of GPER expression versus downregulation of ERα. Reintroduction of GPER significantly attenuated the extent of medial hypertrophy and attenuated the extent of CD45 labeling. Downregulation of ERα expression comparably attenuated the extent of medial hypertrophy and inflammation after carotid ligation. These studies demonstrate that the balance between GPER and ERα regulates vascular remodeling. Receptor-specific modulation of estrogen's effects may be an important new approach in modifying vascular remodeling in both acute settings like vascular injury and perhaps in longer term regulation like in hypertension. © 2016 American Heart Association, Inc.

  15. A role for G-protein coupled estrogen receptor (GPER) in estrogen-induced carcinogenesis: Dysregulated glandular homeostasis, survival and metastasis.

    PubMed

    Filardo, Edward J

    2018-02-01

    Mechanisms of carcinogenesis by estrogen center on its mitogenic and genotoxic potential on tumor target cells. These models suggest that estrogen receptor (ER) signaling promotes expansion of the transformed population and that subsequent accumulation of somatic mutations that drive cancer progression occur via metabolic activation of cathecol estrogens or by epigenetic mechanisms. Recent findings that GPER is linked to obesity, vascular pathology and immunosuppression, key events in the development of metabolic syndrome and intra-tissular estrogen synthesis, provides an alternate view of estrogen-induced carcinogenesis. Consistent with this concept, GPER is directly associated with clinicopathological indices that predict cancer progression and poor survival in breast and gynecological cancers. Moreover, GPER manifests cell biological responses and a microenvironment conducive for tumor development and cancer progression, regulating cellular responses associated with glandular homeostasis and survival, invading surrounding tissue and attracting a vascular supply. Thus, the cellular actions attributed to GPER fit well with the known molecular mechanisms of G-protein coupled receptors, GPCRs, namely, their ability to transactivate integrins and EGF receptors and alter the interaction between glandular epithelia and their extracellular environment, affecting epithelial-to-mesenchymal transition (EMT) and allowing for tumor cell survival and dissemination. This perspective reviews the molecular and cellular responses manifested by GPER and evaluates its contribution to female reproductive cancers as diseases that progress as a result of dysregulated glandular homeostasis resulting in chronic inflammation and metastasis. This review is organized in sections as follows: I) a brief synopsis of the current state of knowledge regarding estrogen-induced carcinogenesis, II) a review of evidence from clinical and animal-based studies that support a role for GPER in cancer

  16. Ritonavir binds to and downregulates estrogen receptors: molecular mechanism of promoting early atherosclerosis.

    PubMed

    Xiang, Jin; Wang, Ying; Su, Ke; Liu, Min; Hu, Peng-Chao; Ma, Tian; Li, Jia-Xi; Wei, Lei; Zheng, Zhongliang; Yang, Fang

    2014-10-01

    Estrogenic actions are closely related to cardiovascular disease. Ritonavir (RTV), a human immunodeficiency virus (HIV) protease inhibitor, induces atherosclerosis in an estrogen-related manner. However, how RTV induce pathological phenotypes through estrogen pathway remains unclear. In this study, we found that RTV increases thickness of coronary artery walls of Sprague Dawley rats and plasma free fatty acids (FFA) levels. In addition, RTV could induce foam cell formation, downregulate both estrogen receptor α (ERα) and ERβ expression, upregulate G protein-coupled estrogen receptor (GPER) expression, and all of them could be partially blocked by 17β-estradiol (E2), suggesting RTV acts as an antagonist for E2. Computational modeling shows a similar interaction with ERα between RTV and 2-aryl indoles, which are highly subtype-selective ligands for ERα. We also found that RTV directly bound to ERα and selectively inhibited the nuclear localization of ERα, and residue Leu536 in the hydrophobic core of ligand binding domain (LBD) was essential for the interaction with RTV. In addition, RTV did not change the secondary structure of ERα-LBD like E2, which explained how ERα lost the capacity of nuclear translocation under the treatment of RTV. All of the evidences suggest that ritonavir acts as an antagonist for 17β-estradiol in regulating α subtype estrogen receptor function and early events of atherosclerosis. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. CERAPP: Collaborative Estrogen Receptor Activity Prediction Project

    EPA Pesticide Factsheets

    Data from a large-scale modeling project called CERAPP (Collaborative Estrogen Receptor Activity Prediction Project) demonstrating using predictive computational models on high-throughput screening data to screen thousands of chemicals against the estrogen receptor.This dataset is associated with the following publication:Mansouri , K., A. Abdelaziz, A. Rybacka, A. Roncaglioni, A. Tropsha, A. Varnek, A. Zakharov, A. Worth, A. Richard , C. Grulke , D. Trisciuzzi, D. Fourches, D. Horvath, E. Benfenati , E. Muratov, E.B. Wedebye, F. Grisoni, G.F. Mangiatordi, G.M. Incisivo, H. Hong, H.W. Ng, I.V. Tetko, I. Balabin, J. Kancherla , J. Shen, J. Burton, M. Nicklaus, M. Cassotti, N.G. Nikolov, O. Nicolotti, P.L. Andersson, Q. Zang, R. Politi, R.D. Beger , R. Todeschini, R. Huang, S. Farag, S.A. Rosenberg, S. Slavov, X. Hu, and R. Judson. (Environmental Health Perspectives) CERAPP: Collaborative Estrogen Receptor Activity Prediction Project. ENVIRONMENTAL HEALTH PERSPECTIVES. National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, NC, USA, 1-49, (2016).

  18. Binding of Estrogenic Compounds to Recombinant Estrogen Receptor-α: Application to Environmental Analysis

    PubMed Central

    Pillon, Arnaud; Boussioux, Anne-Marie; Escande, Aurélie; Aït-Aïssa, Sélim; Gomez, Elena; Fenet, Hélène; Ruff, Marc; Moras, Dino; Vignon, Françoise; Duchesne, Marie-Josèphe; Casellas, Claude; Nicolas, Jean-Claude; Balaguer, Patrick

    2005-01-01

    Estrogenic activity in environmental samples could be mediated through a wide variety of compounds and by various mechanisms. High-affinity compounds for estrogen receptors (ERs), such as natural or synthetic estrogens, as well as low-affinity compounds such as alkylphenols, phthalates, and polychlorinated biphenyls are present in water and sediment samples. Furthermore, compounds such as polycyclic aromatic hydrocarbons, which do not bind ERs, modulate estrogen activity by means of the aryl hydrocarbon receptor (AhR). In order to characterize compounds that mediate estrogenic activity in river water and sediment samples, we developed a tool based on the ER-αligand-binding domain, which permitted us to estimate contaminating estrogenic compound affinities. We designed a simple transactivation assay in which compounds of high affinity were captured by limited amounts of recombinant ER-αand whose capture led to a selective inhibition of transactivation. This approach allowed us to bring to light that water samples contain estrogenic compounds that display a high affinity for ERs but are present at low concentrations. In sediment samples, on the contrary, we showed that estrogenic compounds possess a low affinity and are present at high concentration. Finally, we used immobilized recombinant ER-αto separate ligands for ER and AhR that are present in river sediments. Immobilized ER-α, which does not retain dioxin-like compounds, enabled us to isolate and concentrate ER ligands to facilitate their further analysis. PMID:15743715

  19. Expression and functional roles of G-protein-coupled estrogen receptor (GPER) in human eosinophils.

    PubMed

    Tamaki, Mami; Konno, Yasunori; Kobayashi, Yoshiki; Takeda, Masahide; Itoga, Masamichi; Moritoki, Yuki; Oyamada, Hajime; Kayaba, Hiroyuki; Chihara, Junichi; Ueki, Shigeharu

    2014-07-01

    Sexual dimorphism in asthma links the estrogen and allergic immune responses. The function of estrogen was classically believed to be mediated through its nuclear receptors, i.e., estrogen receptors (ERs). However, recent studies established the important roles of G-protein-coupled estrogen receptor (GPER/GPR30) as a novel membrane receptor for estrogen. To date, the role of GPER in allergic inflammation is poorly understood. The purpose of this study was to examine whether GPER might affect the functions of eosinophils, which play an important role in the pathogenesis of asthma. Here, we demonstrated that GPER was expressed in purified human peripheral blood eosinophils both at the mRNA and protein levels. Although GPER agonist G-1 did not induce eosinophil chemotaxis or chemokinesis, preincubation with G-1 enhanced eotaxin (CCL11)-directed eosinophil chemotaxis. G-1 inhibited eosinophil spontaneous apoptosis and caspase-3 activities. The anti-apoptotic effect was not affected by the cAMP-phospodiesterase inhibitor rolipram or phosphoinositide 3-kinase inhibitors. In contrast to resting eosinophils, G-1 induced apoptosis and increased caspase-3 activities when eosinophils were co-stimulated with IL-5. No effect of G-1 was observed on eosinophil degranulation in terms of release of eosinophil-derived neurotoxin (EDN). The current study indicates the functional capacities of GPER on human eosinophils and also provides the previously unrecognized mechanisms of interaction between estrogen and allergic inflammation. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Activation of Estrogen Receptor Transfected into a Receptor-Negative Brest Cancer Cell Line Decreases the Metastatic and Invasive Potential of the Cells

    NASA Astrophysics Data System (ADS)

    Garcia, Marcel; Derocq, Danielle; Freiss, Gilles; Rochefort, Henri

    1992-12-01

    Breast cancers containing estrogen receptors are responsive to antiestrogen treatment and have a better prognosis than estrogen receptor-negative tumors. The loss of estrogen and progesterone receptors appears to be associated with a progression to less-differentiated tumors. We transfected the human estrogen receptor into the estrogen receptor-negative metastatic breast cancer cell line MDA-MB-231 in an attempt to restore their sensitivity to antiestrogens. Two stable sublines of MDA-MB-231 cells (HC1 and HE5) expressing functional estrogen receptors were studied for their ability to grow and invade in vitro and to metastasize in athymic nude mice. The number and size of lung metastases developed by these two sublines in ovariectomized nude mice was not markedly altered by tamoxifen but was inhibited 3-fold by estradiol. Estradiol also significantly inhibited in vitro cell proliferation of these sublines and their invasiveness in Matrigel, a reconstituted basement membrane, whereas the antiestrogens 4-hydroxytamoxifen and ICI 164,384 reversed these effects. These results show that estradiol inhibits the metastatic ability of estrogen receptornegative breast cancer cells following transfection with the estrogen receptor, whereas estrogen receptor-positive breast cancers are stimulated by estrogen, indicating that factors other than the estrogen receptor are involved in progression toward hormone independence. Reactivation or transfer of the estrogen receptor gene can therefore be considered as therapeutic approaches to hormone-independent cancers

  1. Signaling, physiological functions and clinical relevance of the G protein-coupled estrogen receptor GPER.

    PubMed

    Prossnitz, Eric R; Barton, Matthias

    2009-09-01

    GPR30, now named GPER1 (G protein-coupled estrogen receptor1) or GPER here, was first identified as an orphan 7-transmembrane G protein-coupled receptor by multiple laboratories using either homology cloning or differential expression and subsequently shown to be required for estrogen-mediated signaling in certain cancer cells. The actions of estrogen are extensive in the body and are thought to be mediated predominantly by classical nuclear estrogen receptors that act as transcription factors/regulators. Nevertheless, certain aspects of estrogen function remain incompatible with the generally accepted mechanisms of classical estrogen receptor action. Many recent studies have revealed that GPER contributes to some of the actions of estrogen, including rapid signaling events and rapid transcriptional activation. With the introduction of GPER-selective ligands and GPER knockout mice, the functions of GPER are becoming more clearly defined. In many cases, there appears to be a complex interplay between the two receptor systems, suggesting that estrogen-mediated physiological responses may be mediated by either receptor or a combination of both receptor types, with important medical implications.

  2. Designer interface peptide grafts target estrogen receptor alpha dimerization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chakraborty, S.; Asare, B.K.; Biswas, P.K., E-mail: pbiswas@tougaloo.edu

    The nuclear transcription factor estrogen receptor alpha (ERα), triggered by its cognate ligand estrogen, regulates a variety of cellular signaling events. ERα is expressed in 70% of breast cancers and is a widely validated target for anti-breast cancer drug discovery. Administration of anti-estrogen to block estrogen receptor activation is still a viable anti-breast cancer treatment option but anti-estrogen resistance has been a significant bottle-neck. Dimerization of estrogen receptor is required for ER activation. Blocking ERα dimerization is therefore a complementary and alternative strategy to combat anti-estrogen resistance. Dimer interface peptide “I-box” derived from ER residues 503–518 specifically blocks ER dimerization.more » Recently using a comprehensive molecular simulation we studied the interaction dynamics of ERα LBDs in a homo-dimer. Based on this study, we identified three interface recognition peptide motifs LDKITDT (ERα residues 479–485), LQQQHQRLAQ (residues 497–506), and LSHIRHMSNK (residues 511–520) and reported the suitability of using LQQQHQRLAQ (ER 497–506) as a template to design inhibitors of ERα dimerization. Stability and self-aggregation of peptide based therapeutics poses a significant bottle-neck to proceed further. In this study utilizing peptide grafted to preserve their pharmacophoric recognition motif and assessed their stability and potential to block ERα mediated activity in silico and in vitro. The Grafted peptides blocked ERα mediated cell proliferation and viability of breast cancer cells but did not alter their apoptotic fate. We believe the structural clues identified in this study can be used to identify novel peptidometics and small molecules that specifically target ER dimer interface generating a new breed of anti-cancer agents. - Highlights: • Designer peptide grafts retain core molecular recognition motif during MD simulations. • Designer peptide grafts with Poly-ALA helix form stable

  3. Estrogen Receptor-α Correlates with Higher Fungal Cell Number in Oral Paracoccidioidomycosis in Women.

    PubMed

    Caixeta, Clenivaldo Alves; de Carli, Marina Lara; Ribeiro Júnior, Noé Vital; Sperandio, Felipe Fornias; Nonogaki, Suely; Nogueira, Denismar Alves; Pereira, Alessandro Antônio Costa; Hanemann, João Adolfo Costa

    2018-05-23

    Paracoccidioidomycosis is a neglected tropical fungal infection with great predilection for adult men, indicating the participation of female hormone estrogen in preventing paracoccidioidomycosis development in women. Estrogen has an immunologic effect leading to polarization toward the Th2 immune response, which favors the disease evolution. To evaluate estrogen and progesterone receptors in oral paracoccidioidomycosis lesions and to verify any association with tissue fungi counting in women and men. Thirty-two cases of chronic oral paracoccidioidomycosis were included. Immunohistochemical analyses for anti-estrogen receptor-α, anti-progesterone receptor and anti-Paracoccidioides brasiliensis antibodies were performed. The differences between women and men and the relations among the immunomarkers for each gender were also evaluated. A significant positive correlation was observed between estrogen receptor-α and the amount of fungi in women. In addition, estrogen receptor-α was mildly expressed in the inflammatory cells of female patients, while progesterone receptor was expressed in both genders, with similar expression between women and men. Moreover, fungi counting revealed no differences between genders. Estrogen receptor-α was expressed only in women and showed a positive correlation with the amount of fungi in oral paracoccidioidomycosis, while progesterone receptor was observed in both genders and exhibited no correlation with estrogen receptor-α or fungi counting.

  4. ROLE OF ESTROGEN RECEPTOR-α ON FOOD DEMAND ELASTICITY

    PubMed Central

    Minervini, Vanessa; Rowland, Neil E.; Robertson, Kimberly L.; Foster, Thomas C.

    2016-01-01

    Estrogens have been shown to have an inhibitory effect on food intake under free-feeding conditions, yet the effects of estrogens on food-maintained operant responding have been studied to a much lesser extent and, thus, are not well understood. Therefore, the purpose of the present experiment was to use a behavioral economics paradigm to assess differences in demand elasticity between mice with knockout of the estrogen receptor subtype α, knockout of subtype β, and their wild type controls. The mice responded in a closed economy, and the price of food was increased by increasing the fixed-ratio response requirement every four sessions. Overall, we found that mice with the knockout of receptor subtype α had the most elastic demand functions. Therefore, under these conditions, estrogens increased food seeking via activation of the receptor subtype α. The results were inconsistent with those reported by previous studies that employed free-feeding conditions. PMID:25869426

  5. Role of estrogen receptor-α on food demand elasticity.

    PubMed

    Minervini, Vanessa; Rowland, Neil E; Robertson, Kimberly L; Foster, Thomas C

    2015-05-01

    Estrogens have been shown to have an inhibitory effect on food intake under free-feeding conditions, yet the effects of estrogens on food-maintained operant responding have been studied to a much lesser extent and, thus, are not well understood. Therefore, the purpose of the present experiment was to use a behavioral economics paradigm to assess differences in demand elasticity between mice with knockout of the estrogen receptor subtype α, knockout of subtype β, and their wild type controls. The mice responded in a closed economy, and the price of food was increased by increasing the fixed-ratio response requirement every four sessions. Overall, we found that mice with the knockout of receptor subtype α had the most elastic demand functions. Therefore, under these conditions, estrogens increased food seeking via activation of the receptor subtype α. The results were inconsistent with those reported by previous studies that employed free-feeding conditions. © Society for the Experimental Analysis of Behavior.

  6. The role of estrogens and estrogen receptor signaling pathways in cancer and infertility: the case of schistosomes.

    PubMed

    Botelho, Mónica C; Alves, Helena; Barros, Alberto; Rinaldi, Gabriel; Brindley, Paul J; Sousa, Mário

    2015-06-01

    Schistosoma haematobium, a parasitic flatworm that infects more than 100 million people, mostly in the developing world, is the causative agent of urogenital schistosomiasis, and is associated with a high incidence of squamous cell carcinoma (SCC) of the bladder. Schistosomiasis haematobia also appears to negatively influence fertility, and is particularly associated with female infertility. Given that estrogens and estrogen receptors are key players in human reproduction, we speculate that schistosome estrogen-like molecules may contribute to infertility through hormonal imbalances. Here, we review recent findings on the role of estrogens and estrogen receptors on both carcinogenesis and infertility associated with urogenital schistosomiasis and discuss the basic hormonal mechanisms that might be common in cancer and infertility. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Binding and transactivation of the largemouth bass estrogen receptors by model compounds

    EPA Science Inventory

    Environmental estrogens (EEs) are chemicals in the environment that can elicit adverse effects on estrogen (E2) signaling by binding with the estrogen receptors (ERs). In largemouth bass (LMB), the physiological actions of E2 are primarily mediated via three receptors (ERα, ERßb ...

  8. Estrogen enhances mismatch repair by induction of MLH1 expression via estrogen receptor

    PubMed Central

    Lu, Jun-Yu; Jin, Peng; Gao, Wei; Wang, De-Zhi; Sheng, Jian-Qiu

    2017-01-01

    Epidemiological data demonstrated that hormone replace treatment has protective effect against colorectal cancer (CRC). Our previous studies showed that this effect may be associated with DNA mismatch repair. This study aims to investigate the mechanism of estrogen induction of MLH1, and whether colorectal tumor proliferation can be inhibited through induction of MLH1 by estrogen signal pathway. Human CRC cell lines were used to examine the regulation of MLH1 expression by over-expression and depletion of estrogen receptor-α (ERα) and estrogen receptor-β (ERβ), under the treatment with 17β-estradiol or β-Estradiol 6-(O-carboxy-methyl)oxime:BSA, followed by a real-time Q-PCR and Western blotting analysis. Luciferase reporter and chromatin immunoprecipitation assays were used to identify the estrogen response elements in the proximal promoter of MLH1 gene. Then, the influence of estrogen-induced MLH1 on CRC tumor growth were determined in vitro and in vivo. We found that mismatch repair ability and microsatellite stability of cells were enhanced by estrogen via induction of MLH1 expression, which was mediated by ERβ, through a transcriptional activation process. Furthermore, we identified that ERβ exerted an inhibitory effect on CRC tumor proliferation in vitro and in vivo, combined with 5-FU, through up-regulation of MLH1 expression. Finally, we concluded that estrogen enhances mismatch repair ability and tumor inhibition effect in vitro and in vivo, via induction of MLH1 expression mediated by ERβ. PMID:28404976

  9. Estrogen enhances mismatch repair by induction of MLH1 expression via estrogen receptor-β.

    PubMed

    Lu, Jun-Yu; Jin, Peng; Gao, Wei; Wang, De-Zhi; Sheng, Jian-Qiu

    2017-06-13

    Epidemiological data demonstrated that hormone replace treatment has protective effect against colorectal cancer (CRC). Our previous studies showed that this effect may be associated with DNA mismatch repair. This study aims to investigate the mechanism of estrogen induction of MLH1, and whether colorectal tumor proliferation can be inhibited through induction of MLH1 by estrogen signal pathway. Human CRC cell lines were used to examine the regulation of MLH1 expression by over-expression and depletion of estrogen receptor-α (ERα) and estrogen receptor-β (ERβ), under the treatment with 17β-estradiol or β-Estradiol 6-(O-carboxy-methyl)oxime:BSA, followed by a real-time Q-PCR and Western blotting analysis. Luciferase reporter and chromatin immunoprecipitation assays were used to identify the estrogen response elements in the proximal promoter of MLH1 gene. Then, the influence of estrogen-induced MLH1 on CRC tumor growth were determined in vitro and in vivo. We found that mismatch repair ability and microsatellite stability of cells were enhanced by estrogen via induction of MLH1 expression, which was mediated by ERβ, through a transcriptional activation process. Furthermore, we identified that ERβ exerted an inhibitory effect on CRC tumor proliferation in vitro and in vivo, combined with 5-FU, through up-regulation of MLH1 expression. Finally, we concluded that estrogen enhances mismatch repair ability and tumor inhibition effect in vitro and in vivo, via induction of MLH1 expression mediated by ERβ.

  10. Sex differences in opioid analgesia and addiction: interactions among opioid receptors and estrogen receptors

    PubMed Central

    2013-01-01

    Opioids are widely used as the pain reliever and also notorious for being addictive drugs. Sex differences in the opioid analgesia and addiction have been reported and investigated in human subjects and animal models. Yet, the molecular mechanism underlying the differences between males and females is still unclear. Here, we reviewed the literature describing the sex differences in analgesic responses and addiction liabilities to clinically relevant opioids. The reported interactions among opioids, estrogens, opioid receptors, and estrogen receptors are also evaluated. We postulate that the sex differences partly originated from the crosstalk among the estrogen and opioid receptors when stimulated by the exogenous opioids, possibly through common secondary messengers and the downstream gene transcriptional regulators. PMID:24010861

  11. Estrogen receptor ligands: a patent review update.

    PubMed

    Paterni, Ilaria; Bertini, Simone; Granchi, Carlotta; Macchia, Marco; Minutolo, Filippo

    2013-10-01

    The role of estrogens is mostly mediated by two nuclear receptors (ERα and ERβ) and a membrane-associated G-protein (GPR30 or GPER), and it is not limited to reproduction, but it extends to the skeletal, cardiovascular and central nervous systems. Various pathologies such as cancer, inflammatory, neurodegenerative and metabolic diseases are often associated with dysfunctions of the estrogenic system. Therapeutic interventions by agents that affect the estrogenic signaling pathway might be useful in the treatment of many dissimilar diseases. The massive chemodiversity of ER ligands, limited to patented small molecules, is herein reviewed. The reported compounds are classified on the basis of their chemical structures. Non-steroidal derivatives, which mostly consist of diphenolic compounds, are further segregated into chemical classes based on their central scaffold. Estrogens have been used for almost a century and their earlier applications have concerned interventions in the female reproductive functions, as well as the treatment of some estrogen-dependent cancers and osteoporosis. Since the discovery of ERβ in 1996, the patent literature has started to pay a progressively increasing attention to this newer receptor subtype, which holds promise as a target for new indications, most of which still need to be clinically validated.

  12. Obesity, Insulin Resistance and Diabetes: Sex Differences and Role of Estrogen Receptors

    PubMed Central

    Meyer, Matthias R.; Clegg, Deborah J.; Prossnitz, Eric R.; Barton, Matthias

    2010-01-01

    Obesity increases the risk of coronary artery disease through insulin resistance, diabetes, arterial hypertension, and dyslipidemia. The prevalence of obesity has increased worldwide and is particularly high among middle-aged women and men. After menopause, women are at an increased risk to develop visceral obesity due to the loss of endogenous ovarian hormone production. Effects of estrogens are classically mediated by the two nuclear estrogen receptors (ERs) α and β. In addition, more recent research has shown that the intracellular transmembrane G protein-coupled estrogen receptor, GPER, originally designated as GPR30, also mediates some of the actions attributed to estrogens. Estrogen and its receptors are important regulators of body weight and insulin sensitivity not only in women, but also in men as demonstrated by ER mutations in rodents and humans. This article reviews the role of sex hormones and estrogen receptors in the context of obesity, insulin sensitivity and diabetes as well as the related clinical issues in females and males. PMID:21281456

  13. Computational estimation of rainbow trout estrogen receptor binding affinities for environmental estrogens

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shyu, Conrad; Cavileer, Timothy D.; Nagler, James J.

    2011-02-01

    Environmental estrogens have been the subject of intense research due to their documented detrimental effects on the health of fish and wildlife and their potential to negatively impact humans. A complete understanding of how these compounds affect health is complicated because environmental estrogens are a structurally heterogeneous group of compounds. In this work, computational molecular dynamics simulations were utilized to predict the binding affinity of different compounds using rainbow trout (Oncorhynchus mykiss) estrogen receptors (ERs) as a model. Specifically, this study presents a comparison of the binding affinity of the natural ligand estradiol-17{beta} to the four rainbow trout ER isoformsmore » with that of three known environmental estrogens 17{alpha}-ethinylestradiol, bisphenol A, and raloxifene. Two additional compounds, atrazine and testosterone, that are known to be very weak or non-binders to ERs were tested. The binding affinity of these compounds to the human ER{alpha} subtype is also included for comparison. The results of this study suggest that, when compared to estradiol-17{beta}, bisphenol A binds less strongly to all four receptors, 17{alpha}-ethinylestradiol binds more strongly, and raloxifene has a high affinity for the {alpha} subtype only. The results also show that atrazine and testosterone are weak or non-binders to the ERs. All of the results are in excellent qualitative agreement with the known in vivo estrogenicity of these compounds in the rainbow trout and other fishes. Computational estimation of binding affinities could be a valuable tool for predicting the impact of environmental estrogens in fish and other animals.« less

  14. Participation of Water in the Binding of Estrogen Receptor with Estrogen Responsive Element in vitro.

    PubMed

    Zhu, Guo-Zhang; Tang, Guo-Qing; Ruan, Kang-Cheng; Gong, Yue-Ting; Zhang, Yong-Lian

    1998-01-01

    Many reports have showed that bound water was involved in the interaction between/among the macromolecules. However, it has not been reported whether bound water is also involved in the binding of trans-factors and cis-elements in the regulation of the eukaryotic gene trans-cription or not. Preliminary studies have been made on the effect of bound water on the binding of estrogen receptor with estrogen responsive element in vitro. In the gel retardation assay using the cytosol extract of rat uterus as the supplier of estrogen receptor and 32 bp oligonucleotide containing a concensus vitellogenin A(2) ERE as the probe, various cosolvents, such as glycerol, sucrose, N-dimethylformamide and dimethylsulfoxide, were added respectively to the reaction mixture in varying concentrations to regulate the osmotic pressure. The results indicated that the binding of ER-ERE was enhanced with the increase in the final concentration of these individual cosolvents. On the other hand, when the reaction was carried out under an increasing hydrostatic pressure, the ER-ERE binding was decreased sharply. After decompression the binding of ER-ERE was gradually restored to the normal level with the lapse of time. These results suggested that bound water was directly involved in the binding of ER-ERE and may play an important role in the regulation of the eukaryotic gene transcription.

  15. Channel catfish (Ictalurus punctatus) leukocytes express estrogen receptor isoforms ERα and ERβ2 and are functionally modulated by estrogens

    USGS Publications Warehouse

    Iwanowicz, Luke R.; Stafford, James L.; Patiño, Reynaldo; Bengten, Eva; Miller, Norman W.; Blazer, Vicki

    2014-01-01

    Estrogens are recognized as modulators of immune responses in mammals and teleosts. While it is known that the effects of estrogens are mediated via leukocyte-specific estrogen receptors (ERs) in humans and mice, leucocyte-specific estrogen receptor expression and the effects of estrogens on this cell population is less explored and poorly understood in teleosts. Here in, we verify that channel catfish (Ictalurus punctaus) leukocytes express ERα and ERβ2. Transcripts of these isoforms were detected in tissue-associated leukocyte populations by PCR, but ERβ2 was rarely detected in PBLs. Expression of these receptors was temporally regulated in PBLs following polyclonal activation by concanavalin A, lipopolysaccharide or alloantigen based on evaluation by quantitative and end-point PCR. Examination of long-term leukocyte cell lines demonstrated that these receptors are differentially expressed depending on leukocyte lineage and phenotype. Expression of ERs was also temporally dynamic in some leukocyte lineages and may reflect stage of cell maturity. Estrogens affect the responsiveness of channel catfish peripheral blood leukocytes (PBLs) to mitogens in vitro. Similarly, bactericidal activity and phorbol 12-myristate 13-acetate induced respiratory burst was modulated by 17β-estradiol. These actions were blocked by the pure ER antagonist ICI 182780 indicating that response is, in part, mediated via ERα. In summary, estrogen receptors are expressed in channel catfish leukocytes and participate in the regulation of the immune response. This is the first time leukocyte lineage expression has been reported in teleost cell lines.

  16. Activation of the G protein-coupled estrogen receptor, but not estrogen receptor α or β, rapidly enhances social learning.

    PubMed

    Ervin, Kelsy Sharice Jean; Mulvale, Erin; Gallagher, Nicola; Roussel, Véronique; Choleris, Elena

    2015-08-01

    Social learning is a highly adaptive process by which an animal acquires information from a conspecific. While estrogens are known to modulate learning and memory, much of this research focuses on individual learning. Estrogens have been shown to enhance social learning on a long-term time scale, likely via genomic mechanisms. Estrogens have also been shown to affect individual learning on a rapid time scale through cell-signaling cascades, rather than via genomic effects, suggesting they may also rapidly influence social learning. We therefore investigated the effects of 17β-estradiol and involvement of the estrogen receptors (ERs) using the ERα agonist propyl pyrazole triol, the ERβ agonist diarylpropionitrile, and the G protein-coupled ER 1 (GPER1) agonist G1 on the social transmission of food preferences (STFP) task, within a time scale that focused on the rapid effects of estrogens. General ER activation with 17β-estradiol resulted in a modest facilitation of social learning, with mice showing a preference up to 30min of testing. Specific activation of the GPER1 also rapidly enhanced social learning, with mice showing a socially learned preference up to 2h of testing. ERα activation instead shortened the expression of a socially learned food preference, while ERβ activation had little to no effects. Thus, rapid estrogenic modulation of social learning in the STFP may be the outcome of competing action at the three main receptors. Hence, estrogens' rapid effects on social learning likely depend on the specific ERs present in brain regions recruited during social learning. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Estrogen and estrogen receptor alpha promotes malignancy and osteoblastic tumorigenesis in prostate cancer.

    PubMed

    Mishra, Sweta; Tai, Qin; Gu, Xiang; Schmitz, James; Poullard, Ashley; Fajardo, Roberto J; Mahalingam, Devalingam; Chen, Xiaodong; Zhu, Xueqiong; Sun, Lu-Zhe

    2015-12-29

    The role of estrogen signaling in regulating prostate tumorigenesis is relatively underexplored. Although, an increasing body of evidence has linked estrogen receptor beta (ERß) to prostate cancer, the function of estrogen receptor alpha (ERα) in prostate cancer is not very well studied. We have discovered a novel role of ERα in the pathogenesis of prostate tumors. Here, we show that prostate cancer cells express ERα and estrogen induces oncogenic properties in prostate cancer cells through ERα. Importantly, ERα knockdown in the human prostate cancer PacMetUT1 cells as well as pharmacological inhibition of ERα with ICI 182,780 inhibited osteoblastic lesion formation and lung metastasis in vivo. Co-culture of pre-osteoblasts with cancer cells showed a significant induction of osteogenic markers in the pre-osteoblasts, which was attenuated by knockdown of ERα in cancer cells suggesting that estrogen/ERα signaling promotes crosstalk between cancer and osteoblastic progenitors to stimulate osteoblastic tumorigenesis. These results suggest that ERα expression in prostate cancer cells is essential for osteoblastic lesion formation and lung metastasis. Thus, inhibition of ERα signaling in prostate cancer cells may be a novel therapeutic strategy to inhibit the osteoblastic lesion development as well as lung metastasis in patients with advanced prostate cancer.

  18. Bisphenol AF and Bisphenol B Exert Higher Estrogenic Effects than Bisphenol A via G Protein-Coupled Estrogen Receptor Pathway.

    PubMed

    Cao, Lin-Ying; Ren, Xiao-Min; Li, Chuan-Hai; Zhang, Jing; Qin, Wei-Ping; Yang, Yu; Wan, Bin; Guo, Liang-Hong

    2017-10-03

    Numerous studies have indicated estrogenic disruption effects of bisphenol A (BPA) analogues. Previous mechanistic studies were mainly focused on their genomic activities on nuclear estrogen receptor pathway. However, their nongenomic effects through G protein-coupled estrogen receptor (GPER) pathway remain poorly understood. Here, using a SKBR3 cell-based fluorescence competitive binding assay, we found six BPA analogues bound to GPER directly, with bisphenol AF (BPAF) and bisphenol B (BPB) displaying much higher (∼9-fold) binding affinity than BPA. Molecular docking also demonstrated the binding of these BPA analogues to GPER. By measuring calcium mobilization and cAMP production in SKBR3 cells, we found the binding of these BPA analogues to GPER lead to the activation of subsequent signaling pathways. Consistent with the binding results, BPAF and BPB presented higher agonistic activity than BPA with the lowest effective concentration (LOEC) of 10 nM. Moreover, based on the results of Boyden chamber and wound-healing assays, BPAF and BPB displayed higher activity in promoting GPER mediated SKBR3 cell migration than BPA with the LOEC of 100 nM. Overall, we found two BPA analogues BPAF and BPB could exert higher estrogenic effects than BPA via GPER pathway at nanomolar concentrations.

  19. DNA Repair, Redox Regulation and Modulation of Estrogen Receptor Alpha Mediated Transcription

    ERIC Educational Resources Information Center

    Curtis-Ducey, Carol Dianne

    2009-01-01

    Interaction of estrogen receptor [alpha] (ER[alpha]) with 17[beta]-estradiol (E[subscript 2]) facilitates binding of the receptor to estrogen response elements (EREs) in target genes, which in turn leads to recruitment of coregulatory proteins. To better understand how estrogen-responsive genes are regulated, our laboratory identified a number of…

  20. [Roles of G protein-coupled estrogen receptor in the male reproductive system].

    PubMed

    Chen, Kai-hong; Zhang, Xian; Jiang, Xue-wu

    2016-02-01

    The G protein-coupled estrogen receptor (GPER), also known as G protein-coupled receptor 30 (GPR30), was identified in the recent years as a functional membrane receptor different from the classical nuclear estrogen receptors. This receptor is widely expressed in the cortex, cerebellum, hippocampus, heart, lung, liver, skeletal muscle, and the urogenital system. It is responsible for the mediation of nongenomic effects associated with estrogen and its derivatives, participating in the physiological activities of the body. The present study reviews the molecular structure, subcellular localization, signaling pathways, distribution, and function of GPER in the male reproductive system.

  1. MODELING THE EFFECTS OF FLEXIBILITY ON THE BINDING OF ENVIRONMENTAL ESTROGENS TO THE ESTROGEN RECEPTOR

    EPA Science Inventory

    Modeling the effects of flexibility on the binding of environmental estrogens to the estrogen receptor
    There are many reports of environmental endocrine disruption in the literature, yet it has been difficult to identify the specific chemicals responsible for these effects. ...

  2. G protein-coupled estrogen receptor (GPER) expression in normal and abnormal endometrium.

    PubMed

    Plante, Beth J; Lessey, Bruce A; Taylor, Robert N; Wang, Wei; Bagchi, Milan K; Yuan, Lingwen; Scotchie, Jessica; Fritz, Marc A; Young, Steven L

    2012-07-01

    Rapid estrogen effects are mediated by membrane receptors, and evidence suggests a role for both a membrane-associated form of estrogen receptor alpha (ESR1; ERα) and G-protein coupled receptor 30 (GPER; GPR30). Considering estrogen's importance in endometrial physiology and endometriosis pathophysiology, we hypothesized that GPER could be involved in both cyclic changes in endometrial estrogen action and that aberrant expression might be seen in the eutopic endometrium of women with endometriosis. Using real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemical analysis of normal endometrium, endometrial samples demonstrated cycle-regulated expression of GPER, with maximal expression in the proliferative phase. Eutopic and ectopic endometrium from women with endometriosis overexpressed GPER as compared to eutopic endometrium of normal participants. Ishikawa cells, an adenocarcinoma cell line, expressed GPER, with increased expression upon treatment with estrogen or an ESR1 agonist, but not with a GPER-specific agonist. Decreased expression was seen in Ishikawa cells stably transfected with progesterone receptor A. Together, these data suggest that normal endometrial GPER expression is cyclic and regulated by nuclear estrogen and progesterone receptors, while expression is dysregulated in endometriosis.

  3. Involvement of the orphan nuclear estrogen receptor-related receptor α in osteoclast adhesion and transmigration

    PubMed Central

    Bonnelye, Edith; Saltel, Frédéric; Chabadel, Anne; Zirngibl, Ralph A; Aubin, Jane E; Jurdic, Pierre

    2010-01-01

    The orphan nuclear receptor, estrogen receptor-related receptor α (ERRα) is expressed in osteoblasts and osteoclasts (OCs) and has been proposed to be a modulator of estrogen signaling. To determine the role of ERRα in OC biology, we knocked down ERRα activity by transient transfection of an siRNA directed against ERRα in the RAW264.7 monocyte–macrophage cell line that differentiates into OCs in the presence of receptor activator of nuclear factor κB-ligands and macrophage colony-stimulating factor. In parallel, stable RAW cell lines expressing a dominant-negative form of ERRα and green fluorescent protein (RAW-GFP-ERRαΔAF2) were used. Expression of OC markers was assessed by real-time PCR, and adhesion and transmigration tests were performed. Actin cytoskeletal organization was visualized using confocal microscopy. We found that RAW264.7 cells expressing siRNA directed against ERRα and RAW-GFP-ERRαΔAF2 OCs displayed abnormal spreading, and decreased osteopontin and β3 integrin subunit expression compared with the corresponding control cells. Decreased adhesion and the absence of podosome belts concomitant with abnormal localization of c-src were also observed in RAW-GFP-ERRαΔAF2-derived OCs. In addition, RAW-GFP-ERRαΔAF2-derived OCs failed to transmigrate through osteoblast cell layers. Our data show that the impairment of ERRα function does not alter OC precursor proliferation and differentiation but does alter the adhesion/spreading and migration capacities of mature OCs. PMID:20841427

  4. Estrogens and their receptors in the medial amygdala rapidly facilitate social recognition in female mice.

    PubMed

    Lymer, Jennifer M; Sheppard, Paul A S; Kuun, Talya; Blackman, Andrea; Jani, Nilay; Mahbub, Sahnon; Choleris, Elena

    2018-03-01

    Estrogens have been shown to rapidly (within 1 h) affect learning and memory processes, including social recognition. Both systemic and hippocampal administration of 17β-estradiol facilitate social recognition in female mice within 40 min of administration. These effects were likely mediated by estrogen receptor (ER) α and the G-protein coupled estrogen receptor (GPER), as administration of the respective receptor agonists (PPT and G-1) also facilitated social recognition on a rapid time scale. The medial amygdala has been shown to be necessary for social recognition and long-term manipulations in rats have implicated medial amygdalar ERα. As such, our objective was to investigate whether estrogens and different ERs within the medial amygdala play a role in the rapid facilitation of social recognition in female mice. 17β-estradiol, G-1, PPT, or ERβ agonist DPN was infused directly into the medial amygdala of ovariectomized female mice. Mice were then tested in a social recognition paradigm, which was completed within 40 min, thus allowing the assessment of rapid effects of treatments. 17β-estradiol (10, 25, 50, 100 nM), PPT (300 nM), DPN (150 nM), and G-1 (50 nM) each rapidly facilitated social recognition. Therefore, estrogens in the medial amygdala rapidly facilitate social recognition in female mice, and the three main estrogen receptors: ERα, ERβ, and the GPER all are involved in these effects. This research adds to a network of brain regions, including the medial amygdala and the dorsal hippocampus, that are involved in mediating the rapid estrogenic facilitation of social recognition in female mice. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Estrogen receptor α is required for oviductal transport of embryos

    PubMed Central

    Li, Shuai; O’Neill, Sofia R. S.; Zhang, Yong; Holtzman, Michael J.; Takemaru, Ken-Ichi; Korach, Kenneth S.; Winuthayanon, Wipawee

    2017-01-01

    Newly fertilized embryos spend the first few days within the oviduct and are transported to the uterus, where they implant onto the uterine wall. An implantation of the embryo before reaching the uterus could result in ectopic pregnancy and lead to maternal death. Estrogen is necessary for embryo transport in mammals; however, the mechanism involved in estrogen-mediated cellular function within the oviduct remains unclear. In this study, we show in mouse models that ciliary length and beat frequency of the oviductal epithelial cells are regulated through estrogen receptor α (ESR1) but not estrogen receptor β (ESR2). Gene profiling indicated that transcripts in the WNT/β-catenin (WNT/CTNNB1) signaling pathway were regulated by estrogen in mouse oviduct, and inhibition of this pathway in a whole oviduct culture system resulted in a decreased embryo transport distance. However, selective ablation of CTNNB1 from the oviductal ciliated cells did not affect embryo transport, possibly because of a compensatory mechanism via intact CTNNB1 in the adjacent secretory cells. In summary, we demonstrated that disruption of estrogen signaling in oviductal epithelial cells alters ciliary function and impairs embryo transport. Therefore, our findings may provide a better understanding of etiology of the ectopic pregnancy that is associated with alteration of estrogen signals.—Li, S., O’Neill, S. R. S., Zhang, Y., Holtzman, M. J., Takemaru, K.-I., Korach, K. S., Winuthayanon, W. Estrogen receptor α is required for oviductal transport of embryos. PMID:28082352

  6. Channel catfish (Ictalurus punctatus) leukocytes express estrogen receptor isoforms ERα and ERβ2 and are functionally modulated by estrogens.

    PubMed

    Iwanowicz, Luke R; Stafford, James L; Patiño, Reynaldo; Bengten, Eva; Miller, Norman W; Blazer, Vicki S

    2014-09-01

    Estrogens are recognized as modulators of immune responses in mammals and teleosts. While it is known that the effects of estrogens are mediated via leukocyte-specific estrogen receptors (ERs) in humans and mice, leucocyte-specific estrogen receptor expression and the effects of estrogens on this cell population is less explored and poorly understood in teleosts. Here in, we verify that channel catfish (Ictalurus punctaus) leukocytes express ERα and ERβ2. Transcripts of these isoforms were detected in tissue-associated leukocyte populations by PCR, but ERβ2 was rarely detected in PBLs. Expression of these receptors was temporally regulated in PBLs following polyclonal activation by concanavalin A, lipopolysaccharide or alloantigen based on evaluation by quantitative and end-point PCR. Examination of long-term leukocyte cell lines demonstrated that these receptors are differentially expressed depending on leukocyte lineage and phenotype. Expression of ERs was also temporally dynamic in some leukocyte lineages and may reflect stage of cell maturity. Estrogens affect the responsiveness of channel catfish peripheral blood leukocytes (PBLs) to mitogens in vitro. Similarly, bactericidal activity and phorbol 12-myristate 13-acetate induced respiratory burst was modulated by 17β-estradiol. These actions were blocked by the pure ER antagonist ICI 182780 indicating that response is, in part, mediated via ERα. In summary, estrogen receptors are expressed in channel catfish leukocytes and participate in the regulation of the immune response. This is the first time leukocyte lineage expression has been reported in teleost cell lines. Published by Elsevier Ltd.

  7. Estrogen Receptor β Activation Rapidly Modulates Male Sexual Motivation through the Transactivation of Metabotropic Glutamate Receptor 1a

    PubMed Central

    Seredynski, Aurore L.; Balthazart, Jacques; Ball, Gregory F.

    2015-01-01

    In addition to the transcriptional activity of their liganded nuclear receptors, estrogens, such as estradiol (E2), modulate cell functions, and consequently physiology and behavior, within minutes through membrane-initiated events. The membrane-associated receptors (mERs) underlying the acute effects of estrogens on behavior have mostly been documented in females where active estrogens are thought to be of ovarian origin. We determined here, by acute intracerebroventricular injections of specific agonists and antagonists, the type(s) of mERs that modulate rapid effects of brain-derived estrogens on sexual motivation in male Japanese quail. Brain aromatase blockade acutely inhibited sexual motivation. Diarylpropionitrile (DPN), an estrogen receptor β (ERβ)-specific agonist, and to a lesser extent 17α-estradiol, possibly acting through ER-X, prevented this effect. In contrast, drugs targeting ERα (PPT and MPP), GPR30 (G1 and G15), and the Gq-mER (STX) did not affect sexual motivation. The mGluR1a antagonist LY367385 significantly inhibited sexual motivation but mGluR2/3 and mGluR5 antagonists were ineffective. LY367385 also blocked the behavioral restoration induced by E2 or DPN, providing functional evidence that ERβ interacts with metabotropic glutamate receptor 1a (mGluR1a) signaling to acutely regulate male sexual motivation. Together these results show that ERβ plays a key role in sexual behavior regulation and the recently uncovered cooperation between mERs and mGluRs is functional in males where it mediates the acute effects of estrogens produced centrally in response to social stimuli. The presence of an ER–mGluR interaction in birds suggests that this mechanism emerged relatively early in vertebrate history and is well conserved. SIGNIFICANCE STATEMENT The membrane-associated receptors underlying the acute effects of estrogens on behavior have mostly been documented in females, where active estrogens are thought to be of ovarian origin. Using acute

  8. Estrogen Receptor β Activation Rapidly Modulates Male Sexual Motivation through the Transactivation of Metabotropic Glutamate Receptor 1a.

    PubMed

    Seredynski, Aurore L; Balthazart, Jacques; Ball, Gregory F; Cornil, Charlotte A

    2015-09-23

    In addition to the transcriptional activity of their liganded nuclear receptors, estrogens, such as estradiol (E2), modulate cell functions, and consequently physiology and behavior, within minutes through membrane-initiated events. The membrane-associated receptors (mERs) underlying the acute effects of estrogens on behavior have mostly been documented in females where active estrogens are thought to be of ovarian origin. We determined here, by acute intracerebroventricular injections of specific agonists and antagonists, the type(s) of mERs that modulate rapid effects of brain-derived estrogens on sexual motivation in male Japanese quail. Brain aromatase blockade acutely inhibited sexual motivation. Diarylpropionitrile (DPN), an estrogen receptor β (ERβ)-specific agonist, and to a lesser extent 17α-estradiol, possibly acting through ER-X, prevented this effect. In contrast, drugs targeting ERα (PPT and MPP), GPR30 (G1 and G15), and the Gq-mER (STX) did not affect sexual motivation. The mGluR1a antagonist LY367385 significantly inhibited sexual motivation but mGluR2/3 and mGluR5 antagonists were ineffective. LY367385 also blocked the behavioral restoration induced by E2 or DPN, providing functional evidence that ERβ interacts with metabotropic glutamate receptor 1a (mGluR1a) signaling to acutely regulate male sexual motivation. Together these results show that ERβ plays a key role in sexual behavior regulation and the recently uncovered cooperation between mERs and mGluRs is functional in males where it mediates the acute effects of estrogens produced centrally in response to social stimuli. The presence of an ER-mGluR interaction in birds suggests that this mechanism emerged relatively early in vertebrate history and is well conserved. Significance statement: The membrane-associated receptors underlying the acute effects of estrogens on behavior have mostly been documented in females, where active estrogens are thought to be of ovarian origin. Using acute

  9. Species comparisons in molecular and functional attributes of the androgen and estrogen receptor

    EPA Science Inventory

    While endocrine disrupting compounds (EDCs) have the potential to act via several mechanisms of action, one of the most widely studied is the ability of environmental chemicals to interact directly with either the estrogen (ER) or androgen receptor (AR). In vitro screening assay...

  10. Tamoxifen induces the expression of maspin through estrogen receptor-alpha.

    PubMed

    Liu, Zesheng; Shi, Heidi Y; Nawaz, Zafar; Zhang, Ming

    2004-06-08

    Maspin (mammary serine protease inhibitor) is a tumor suppressor gene that plays an important role in inhibiting tumor growth, invasion and metastasis. Maspin expression is down regulated at transcription level in primary and metastatic breast tumor cells. Previous studies on hormonal regulation of maspin prompt us to test whether an estrogen antagonist tamoxifen (TAM) can exert its anti-tumor function by up regulating maspin gene expression. For this purpose, we first tested whether maspin promoter could be activated in normal and several breast tumor cells. We then carried out a series of promoter analysis in which estrogen receptors and TAM were reconstituted in an in vitro cell culture system. Here we report our new finding that tumor suppresser gene maspin is one of the TAM target genes. TAM induces a maspin/luciferase reporter in cell culture and this induction requires the presence of (estrogen receptor alpha) ERalpha but not estrogen receptor-beta (ERbeta). Maspin promoter deletion and mutation analysis showed that the cis element(s) within a region between -90and+87 bp but not the HRE site (-272 bp) was involved in TAM induction of maspin expression. TAM bound ERalpha may directly control maspin gene expression through the interaction with cofactor (s). Analysis using several ERalpha mutants showed that the N-terminal A/B motif (AF-1) was critical for maspin basal level transcription activation. An ERalpha mutant with point mutations at DNA binding domain abolished estrogen induction of an ERE-luciferase reporter but was still active in activating maspin promoter by TAM. LBD-AF2 domain was required for ERalpha-dependent TAM induction. Deletion of LBD-AF2 or a point mutation in the ERalpha LBD-AF2 region (LBDmtL539A) completely abolished the activation of maspin promoter, suggesting that TAM induction of maspin involves the recruitment of cofactor(s) by ERalpha to the maspin promoter region. This finding indicates that one of the pathways for cancer

  11. Estrogen receptor agonists/antagonists in breast cancer therapy: A critical review.

    PubMed

    Jameera Begam, A; Jubie, S; Nanjan, M J

    2017-04-01

    Estrogens display intriguing tissue selective action that is of great biomedical importance in the development of optimal therapeutics for the prevention and treatment of breast cancer. There are also strong evidences to show that both endogenous and exogenous estrogens are involved in the pathogenesis of breast cancer. Tamoxifen has been the only drug of choice for more than 30years to treat patients with estrogen related (ER) positive breast tumors. There is a need therefore, for identifying newer, potential and novel candidates for breast cancer. Keeping this in view, the present review focuses on selective estrogen receptor modulators and estrogen antagonists such as sulfatase and aromatase inhibitors involved in breast cancer therapy. A succinct and critical overview of the structure of estrogen receptors, their signaling and involvement in breast carcinogenesis are herein described. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Estrogen receptor signaling in prostate cancer: Implications for carcinogenesis and tumor progression.

    PubMed

    Bonkhoff, Helmut

    2018-01-01

    The androgen receptor (AR) is the classical target for prostate cancer prevention and treatment, but more recently estrogens and their receptors have also been implicated in prostate cancer development and tumor progression. Recent experimental and clinical data were reviewed to elucidate pathogenetic mechanisms how estrogens and their receptors may affect prostate carcinogenesis and tumor progression. The estrogen receptor beta (ERβ) is the most prevalent ER in the human prostate, while the estrogen receptor alpha (ERα) is restricted to basal cells of the prostatic epithelium and stromal cells. In high grade prostatic intraepithelial neoplasia (HGPIN), the ERα is up-regulated and most likely mediates carcinogenic effects of estradiol as demonstrated in animal models. The partial loss of the ERβ in HGPIN indicates that the ERβ acts as a tumor suppressor. The tumor promoting function of the TMPRSS2-ERG fusion, a major driver of prostate carcinogenesis, is triggered by the ERα and repressed by the ERβ. The ERβ is generally retained in hormone naïve and metastatic prostate cancer, but is partially lost in castration resistant disease. The progressive emergence of the ERα and ERα-regulated genes (eg, progesterone receptor (PR), PS2, TMPRSS2-ERG fusion, and NEAT1) during prostate cancer progression and hormone refractory disease suggests that these tumors can bypass the AR by using estrogens and progestins for their growth. In addition, nongenomic estrogen signaling pathways mediated by orphan receptors (eg, GPR30 and ERRα) has also been implicated in prostate cancer progression. Increasing evidences demonstrate that local estrogen signaling mechanisms are required for prostate carcinogenesis and tumor progression. Despite the recent progress in this research topic, the translation of the current information into potential therapeutic applications remains highly challenging and clearly warrants further investigation. © 2017 Wiley Periodicals, Inc.

  13. G Protein-Coupled Estrogen Receptor (GPER) Expression in Normal and Abnormal Endometrium

    PubMed Central

    Lessey, Bruce A.; Taylor, Robert N.; Wang, Wei; Bagchi, Milan K.; Yuan, Lingwen; Scotchie, Jessica; Fritz, Marc A.; Young, Steven L.

    2012-01-01

    Rapid estrogen effects are mediated by membrane receptors, and evidence suggests a role for both a membrane-associated form of estrogen receptor alpha (ESR1; ERα) and G-protein coupled receptor 30 (GPER; GPR30). Considering estrogen’s importance in endometrial physiology and endometriosis pathophysiology, we hypothesized that GPER could be involved in both cyclic changes in endometrial estrogen action and that aberrant expression might be seen in the eutopic endometrium of women with endometriosis. Using real-time reverse transcriptase–polymerase chain reaction (RT-PCR) and immunohistochemical analysis of normal endometrium, endometrial samples demonstrated cycle-regulated expression of GPER, with maximal expression in the proliferative phase. Eutopic and ectopic endometrium from women with endometriosis overexpressed GPER as compared to eutopic endometrium of normal participants. Ishikawa cells, an adenocarcinoma cell line, expressed GPER, with increased expression upon treatment with estrogen or an ESR1 agonist, but not with a GPER-specific agonist. Decreased expression was seen in Ishikawa cells stably transfected with progesterone receptor A. Together, these data suggest that normal endometrial GPER expression is cyclic and regulated by nuclear estrogen and progesterone receptors, while expression is dysregulated in endometriosis. PMID:22378861

  14. Twenty years of the G protein-coupled estrogen receptor GPER: Historical and personal perspectives.

    PubMed

    Barton, Matthias; Filardo, Edward J; Lolait, Stephen J; Thomas, Peter; Maggiolini, Marcello; Prossnitz, Eric R

    2018-02-01

    Estrogens play a critical role in many aspects of physiology, particularly female reproductive function, but also in pathophysiology, and are associated with protection from numerous diseases in premenopausal women. Steroids and the effects of estrogen have been known for ∼90 years, with the first evidence for a receptor for estrogen presented ∼50 years ago. The original ancestral steroid receptor, extending back into evolution more than 500 million years, was likely an estrogen receptor, whereas G protein-coupled receptors (GPCRs) trace their origins back into history more than one billion years. The classical estrogen receptors (ERα and ERβ) are ligand-activated transcription factors that confer estrogen sensitivity upon many genes. It was soon apparent that these, or novel receptors may also be responsible for the "rapid"/"non-genomic" membrane-associated effects of estrogen. The identification of an orphan GPCR (GPR30, published in 1996) opened a new field of research with the description in 2000 that GPR30 expression is required for rapid estrogen signaling. In 2005-2006, the field was greatly stimulated by two studies that described the binding of estrogen to GPR30-expressing cell membranes, followed by the identification of a GPR30-selective agonist (that lacked binding and activity towards ERα and ERβ). Renamed GPER (G protein-coupled estrogen receptor) by IUPHAR in 2007, the total number of articles in PubMed related to this receptor recently surpassed 1000. In this article, the authors present personal perspectives on how they became involved in the discovery and/or advancement of GPER research. These areas include non-genomic effects on vascular tone, receptor cloning, molecular and cellular biology, signal transduction mechanisms and pharmacology of GPER, highlighting the roles of GPER and GPER-selective compounds in diseases such as obesity, diabetes, and cancer and the obligatory role of GPER in propagating cardiovascular aging, arterial

  15. Estrogen receptors and ischemic neuroprotection: who, what, where, and when?

    PubMed

    Schreihofer, Derek A; Ma, Yulin

    2013-06-13

    Estrogens, particularly 17β-estradiol (E2), are powerful neuroprotective agents in animal models of cerebral ischemia. Loss of endogenous E2 in women at menopause or after surgical oopherectomy leads to an increase risk of stroke, neurodegenerative disease, and cognitive decline. However, several clinical trials found detrimental effects of E2 therapy after menopause, including increased stroke risk and dementia. Recent animal and human studies now support the "critical period" hypothesis for E2 neuroprotection whereby E2 therapy must begin soon after the loss of endogenous E2 production to have a beneficial effect. Although a wide array of mechanisms has been proposed for estradiol (E2)-dependent neuroprotection in cerebral ischemia and neurodegenerative disease, most of these mechanisms involve interactions of E2 with one of its cognate receptors, estrogen receptor alpha (ERα), estrogen receptor beta (ERβ), or the G protein-coupled estrogen receptor (GPER). However, these receptors are not uniformly distributed throughout the brain, across different cell types, and within cellular compartments. Such differences likely play a role in the ability of E2 and ER selective ligands to protect the brain from ischemia. This review examines the changes in ER expression and location that may underlie the loss of E2 neuroprotection seen with aging and long-term estrogen deprivation (LTED). Recent results suggest that the loss of ERα that accompanies aging and LTED plays an important role in the loss of E2-dependent neuroprotection. This article is part of a Special Issue entitled Hormone Therapy. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Coordinate regulation of estrogen-mediated fibronectin matrix assembly and epidermal growth factor receptor transactivation by the G protein-coupled receptor, GPR30.

    PubMed

    Quinn, Jeffrey A; Graeber, C Thomas; Frackelton, A Raymond; Kim, Minsoo; Schwarzbauer, Jean E; Filardo, Edward J

    2009-07-01

    Estrogen promotes changes in cytoskeletal architecture not easily attributed to the biological action of estrogen receptors, ERalpha and ERbeta. The Gs protein-coupled transmembrane receptor, GPR30, is linked to specific estrogen binding and rapid estrogen-mediated release of heparin-bound epidermal growth factor. Using marker rescue and dominant interfering mutant strategies, we show that estrogen action via GPR30 promotes fibronectin (FN) matrix assembly by human breast cancer cells. Stimulation with 17beta-estradiol or the ER antagonist, ICI 182, 780, results in the recruitment of FN-engaged integrin alpha5beta1 conformers to fibrillar adhesions and the synthesis of FN fibrils. Concurrent with this cellular response, GPR30 promotes the formation of Src-dependent, Shc-integrin alpha5beta1 complexes. Function-blocking antibodies directed against integrin alpha5beta1 or soluble Arg-Gly-Asp peptide fragments derived from FN specifically inhibited GPR30-mediated epidermal growth factor receptor transactivation. Estrogen-mediated FN matrix assembly and epidermal growth factor receptor transactivation were similarly disrupted in integrin beta1-deficient GE11 cells, whereas reintroduction of integrin beta1 into GE11 cells restored these responses. Mutant Shc (317Y/F) blocked GPR30-induced FN matrix assembly and tyrosyl phosphorylation of erbB1. Interestingly, relative to recombinant wild-type Shc, 317Y/F Shc was more readily retained in GPR30-induced integrin alpha5beta1 complexes, yet this mutant did not prevent endogenous Shc-integrin alpha5beta1 complex formation. Our results suggest that GPR30 coordinates estrogen-mediated FN matrix assembly and growth factor release in human breast cancer cells via a Shc-dependent signaling mechanism that activates integrin alpha5beta1.

  17. Glyphosate induces growth of estrogen receptor alpha positive cholangiocarcinoma cells via non-genomic estrogen receptor/ERK1/2 signaling pathway.

    PubMed

    Sritana, Narongrit; Suriyo, Tawit; Kanitwithayanun, Jantamas; Songvasin, Benjaporn Homkajorn; Thiantanawat, Apinya; Satayavivad, Jutamaad

    2018-06-08

    Previous studies showed that glyphosate stimulates breast cancer cell growth via estrogen receptors. The present study investigated the effect of glyphosate on the estrogen signaling pathway involved in the induction of cholangiocarcinoma (CCA) cell growth. HuCCA-1, RMCCA-1 and MMNK-1 were chosen for comparison. The effects of glyphosate on cell growth, cell cycle and molecular signaling pathways were measured. The results showed that HuCCA-1 cells expressed estrogen receptor alpha (ERα), while ERα was not detected in RMCCA-1 and MMNK-1 cells. ERα was mostly expressed in cytoplasmic compartment of HuCCA-1 cells. Estradiol (E2) (10 -11 -10 -5  M) induced cell proliferation in HuCCA-1 but not in RMCCA-1 and MMNK-1 cells. Glyphosate at the same concentration range also induced HuCCA-1 cell proliferation. The S phase of the cell cycle, and protein levels of the cyclin family were significantly increased after treatment of glyphosate or E2. Both compounds also induced the expression of proliferative signaling-related proteins including ERα, VEGFR2, pERK, PI3K(p85), and PCNA. These effects of glyphosate and E2 were abolished by the ER antagonist, 4-hydroxytamoxifen and U0126, a MEK inhibitor. The data from this study indicate that glyphosate can induce cell growth in ERα positive CCA cells through non-genomic estrogen receptor/ERK1/2 signaling pathway. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Phytoestrogens and Mycoestrogens Induce Signature Structure Dynamics Changes on Estrogen Receptor α

    PubMed Central

    Chen, Xueyan; Uzuner, Ugur; Li, Man; Shi, Weibing; Yuan, Joshua S.; Dai, Susie Y.

    2016-01-01

    Endocrine disrupters include a broad spectrum of chemicals such as industrial chemicals, natural estrogens and androgens, synthetic estrogens and androgens. Phytoestrogens are widely present in diet and food supplements; mycoestrogens are frequently found in grains. As human beings and animals are commonly exposed to phytoestrogens and mycoestrogens in diet and environment, it is important to understand the potential beneficial or hazardous effects of estrogenic compounds. Many bioassays have been established to study the binding of estrogenic compounds with estrogen receptor (ER) and provided rich data in the literature. However, limited assays can offer structure information with regard to the ligand/ER complex. Our current study surveys the global structure dynamics changes for ERα ligand binding domain (LBD) when phytoestrogens and mycoestrogens bind. The assay is based on the structure dynamics information probed by hydrogen deuterium exchange mass spectrometry and offers a unique viewpoint to elucidate the mechanism how phytoestrogens and mycoestrogens interact with estrogen receptor. The cluster analysis based on the hydrogen deuterium exchange (HDX) assay data reveals a unique pattern when phytoestrogens and mycoestrogens bind with ERα LBD compared to that of estradiol and synthetic estrogen modulators. Our study highlights that structure dynamics could play an important role in the structure function relationship when endocrine disrupters interact with estrogen receptors. PMID:27589781

  19. Calmodulin Lobes Facilitate Dimerization and Activation of Estrogen Receptor-α*

    PubMed Central

    Li, Zhigang; Zhang, Yonghong; Hedman, Andrew C.; Ames, James B.

    2017-01-01

    Estrogen receptor α (ER-α) is a nuclear hormone receptor that controls selected genes, thereby regulating proliferation and differentiation of target tissues, such as breast. Gene expression controlled by ER-α is modulated by Ca2+ via calmodulin (CaM). Here we present the NMR structure of Ca2+-CaM bound to two molecules of ER-α (residues 287–305). The two lobes of CaM bind to the same site on two separate ER-α molecules (residues 292, 296, 299, 302, and 303), which explains why CaM binds two molecules of ER-α in a 1:2 complex and stabilizes ER-α dimerization. Exposed glutamate residues in CaM (Glu-11, Glu-14, Glu-84, and Glu-87) form salt bridges with key lysine residues in ER-α (Lys-299, Lys-302, and Lys-303), which is likely to prevent ubiquitination at these sites and inhibit degradation of ER-α. Transfection of cells with full-length CaM slightly increased the ability of estrogen to enhance transcriptional activation by ER-α of endogenous estrogen-responsive genes. By contrast, expression of either the N- or C-lobe of CaM abrogated estrogen-stimulated transcription of the estrogen responsive genes pS2 and progesterone receptor. These data suggest that CaM-induced dimerization of ER-α is required for estrogen-stimulated transcriptional activation by the receptor. In light of the critical role of ER-α in breast carcinoma, our data suggest that small molecules that selectively disrupt the interaction of ER-α with CaM may be useful in the therapy of breast carcinoma. PMID:28174300

  20. Role of estrogen receptors alpha, beta and GPER1/GPR30 in pancreatic beta-cells.

    PubMed

    Nadal, Angel; Alonso-Magdalena, Paloma; Soriano, Sergi; Ripoll, Cristina; Fuentes, Esther; Quesada, Ivan; Ropero, Ana Belen

    2011-01-01

    Estrogen receptors (ER) are emerging as important molecules involved in the adaptation of beta-cells to insulin resistance. The onset of type 2 diabetes is marked by insulin secretory dysfunction and decreased beta-cell mass. During pregnancy, puberty and obesity there is increased metabolic demand and insulin resistance is developed. This metabolic state increases the demand on beta-cells to augment insulin biosynthesis and release. In this respect, ERalpha is directly implicated in the E2-regulation of insulin content and secretion, while ERbeta is in the E2-potentiation of glucose-induced insulin release. Both receptors develop their actions within the physiological range of E2. In addition, the G protein-coupled estrogen receptor (GPER1/GPR30) seems to be implicated in the E2-regulation of stimulus-secretion coupling in the three cell types of the islet. The increased demand of insulin production for long time may lead to beta-cell stress and apoptosis. ERalpha, ERbeta and GPER1/GPR30 are involved in preventing beta-cell apoptosis, impeding the loss of critical beta-cell mass. Therefore, estrogen receptors may play an essential role in the adaptation of the pancreas to insulin resistant periods.

  1. The Expanding Complexity of Estrogen Receptor Signaling in the Cardiovascular System

    PubMed Central

    Menazza, Sara; Murphy, Elizabeth

    2016-01-01

    Estrogen has important effects on cardiovascular function including regulation of vascular function, blood pressure, endothelial relaxation, the development of hypertrophy and cardioprotection. However, the mechanisms by which estrogen mediates these effects are still poorly understood. As detailed in this review, estrogen can regulate transcription by binding to two nuclear receptors, ERα and ERβ, which differentially regulate gene transcription. ERα and ERβ regulation of gene transcription is further modulated by tissue specific co-activators and co-repressors. Estrogen can bind to ERα and ERβ localized at the plasma membrane as well as GPER to initiate membrane delimited signaling, which enhances kinase signaling pathways that can have acute and long term effects. The kinase signaling pathways can also mediate transcriptional changes, and can synergize with the estrogen receptor to regulate cell function. This review will summarize the beneficial effects of estrogen in protecting the cardiovascular system through ER-dependent mechanisms with an emphasis on the role of the recently described ER-membrane signaling mechanisms. PMID:26838792

  2. Recurrence of Cervical Cancer in Mice after Selective Estrogen Receptor Modulator Therapy

    PubMed Central

    Spurgeon, Megan E.; Chung, Sang-Hyuk; Lambert, Paul F.

    2015-01-01

    Estrogen and its nuclear receptor, estrogen receptor α, are necessary cofactors in the initiation and multistage progression of carcinogenesis in the K14E6/E7 transgenic mouse model of human papillomavirus–associated cervical cancer. Recently, our laboratory reported that raloxifene, a selective estrogen receptor modulator, promoted regression of high-grade dysplasia and cancer that arose in the cervix of K14E6/E7 transgenic mice treated long-term with estrogen. Herein, we evaluated the recurrence of cervical cancer after raloxifene therapy in our preclinical model of human papillomavirus–associated cervical carcinogenesis. We observed recurrence of cervical cancer in mice re-exposed to estrogen after raloxifene treatment, despite evidence suggesting the antagonistic effects of raloxifene persisted in the reproductive tract after treatment had ceased. We also observed recurrence of neoplastic disease in mice that were not retreated with exogenous estrogen, although the severity of disease was less. Recurrent neoplastic disease and cancers retained functional estrogen receptor α and responded to retreatment with raloxifene. Moreover, continuous treatment of mice with raloxifene prevented the emergence of recurrent disease seen in mice in which raloxifene was discontinued. These data suggest that cervical cancer cells are not completely eradicated by raloxifene and rapidly expand if raloxifene treatment is ceased. These findings indicate that a prolonged treatment period with raloxifene might be required to prevent recurrence of neoplastic disease and lower reproductive tract cancers. PMID:24418098

  3. Melanocortin 4 receptor is not required for estrogenic regulations on energy homeostasis and reproduction.

    PubMed

    Xu, Pingwen; Zhu, Liangru; Saito, Kenji; Yang, Yongjie; Wang, Chunmei; He, Yanlin; Yan, Xiaofeng; Hyseni, Ilirjana; Tong, Qingchun; Xu, Yong

    2017-05-01

    Brain estrogen receptor-α (ERα) is essential for estrogenic regulation of energy homeostasis and reproduction. We previously showed that ERα expressed by pro-opiomelanocortin (POMC) neurons mediates estrogen's effects on food intake, body weight, negative regulation of hypothalamic-pituitary-gonadal axis (HPG axis) and fertility. We report here that global deletion of a key downstream receptor for POMC peptide, the melanocortin 4 receptor (MC4R), did not affect normal negative feedback regulation of estrogen on the HPG axis, estrous cyclicity and female fertility. Furthermore, loss of the MC4R did not influence estrogenic regulation on food intake and body weight. These results indicate that the MC4R is not required for estrogen's effects on metabolic and reproductive functions. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. G protein-coupled estrogen receptor and estrogen receptor ligands regulate colonic motility and visceral pain.

    PubMed

    Zielińska, M; Fichna, J; Bashashati, M; Habibi, S; Sibaev, A; Timmermans, J-P; Storr, M

    2017-07-01

    Diarrhea-predominant irritable bowel syndrome (IBS-D) is a functional gastrointestinal (GI) disorder, which occurs more frequently in women than men. The aim of our study was to determine the role of activation of classical estrogen receptors (ER) and novel membrane receptor, G protein-coupled estrogen receptor (GPER) in human and mouse tissue and to assess the possible cross talk between these receptors in the GI tract. Immunohistochemistry was used to determine the expression of GPER in human and mouse intestines. The effect of G-1, a GPER selective agonist, and estradiol, a non-selective ER agonist, on muscle contractility was characterized in isolated preparations of the human and mouse colon. To characterize the effect of G-1 and estradiol in vivo, colonic bead expulsion test was performed. G-1 and estradiol activity on the visceral pain signaling was assessed in the mustard oil-induced abdominal pain model. GPER is expressed in the human colon and in the mouse colon and ileum. G-1 and estradiol inhibited muscle contractility in vitro in human and mouse colon. G-1 or estradiol administered intravenously at the dose of 20 mg/kg significantly prolonged the time to bead expulsion in females. Moreover, G-1 prolonged the time to bead expulsion and inhibited GI hypermotility in both genders. The injection of G-1 or estradiol resulted in a significant reduction in the number of pain-induced behaviors in mice. GPER and ER receptors are involved in the regulation of GI motility and visceral pain. Both may thus constitute an important pharmacological target in the IBS-D therapy. © 2017 John Wiley & Sons Ltd.

  5. Combinations of physiologic estrogens with xenoestrogens alter calcium and kinase responses, prolactin release, and membrane estrogen receptor trafficking in rat pituitary cells

    PubMed Central

    2010-01-01

    Background Xenoestrogens such as alkylphenols and the structurally related plastic byproduct bisphenol A have recently been shown to act potently via nongenomic signaling pathways and the membrane version of estrogen receptor-α. Though the responses to these compounds are typically measured individually, they usually contaminate organisms that already have endogenous estrogens present. Therefore, we used quantitative medium-throughput screening assays to measure the effects of physiologic estrogens in combination with these xenoestrogens. Methods We studied the effects of low concentrations of endogenous estrogens (estradiol, estriol, and estrone) at 10 pM (representing pre-development levels), and 1 nM (representing higher cycle-dependent and pregnancy levels) in combinations with the same levels of xenoestrogens in GH3/B6/F10 pituitary cells. These levels of xenoestrogens represent extremely low contamination levels. We monitored calcium entry into cells using Fura-2 fluorescence imaging of single cells. Prolactin release was measured by radio-immunoassay. Extracellular-regulated kinase (1 and 2) phospho-activations and the levels of three estrogen receptors in the cell membrane (ERα, ERβ, and GPER) were measured using a quantitative plate immunoassay of fixed cells either permeabilized or nonpermeabilized (respectively). Results All xenoestrogens caused responses at these concentrations, and had disruptive effects on the actions of physiologic estrogens. Xenoestrogens reduced the % of cells that responded to estradiol via calcium channel opening. They also inhibited the activation (phosphorylation) of extracellular-regulated kinases at some concentrations. They either inhibited or enhanced rapid prolactin release, depending upon concentration. These latter two dose-responses were nonmonotonic, a characteristic of nongenomic estrogenic responses. Conclusions Responses mediated by endogenous estrogens representing different life stages are vulnerable to very

  6. Ketamine and ketamine metabolites as novel estrogen receptor ligands: Induction of cytochrome P450 and AMPA glutamate receptor gene expression.

    PubMed

    Ho, Ming-Fen; Correia, Cristina; Ingle, James N; Kaddurah-Daouk, Rima; Wang, Liewei; Kaufmann, Scott H; Weinshilboum, Richard M

    2018-04-03

    Major depressive disorder (MDD) is the most common psychiatric illness worldwide, and it displays a striking sex-dependent difference in incidence, with two thirds of MDD patients being women. Ketamine treatment can produce rapid antidepressant effects in MDD patients, effects that are mediated-at least partially-through glutamatergic neurotransmission. Two active metabolites of ketamine, (2R,6R)-hydroxynorketamine (HNK) and (2S,6S)-HNK, also appear to play a key role in ketamine's rapid antidepressant effects through the activation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptors. In the present study, we demonstrated that estrogen plus ketamine or estrogen plus active ketamine metabolites displayed additive effects on the induction of the expression of AMPA receptor subunits. In parallel, the expression of estrogen receptor alpha (ERα) was also significantly upregulated. Even more striking, radioligand binding assays demonstrated that [ 3 H]-ketamine can directly bind to ERα (K D : 344.5 ± 13 nM). Furthermore, ketamine and its (2R,6R)-HNK and (2S,6S)-HNK metabolites displayed similar affinity for ERα (IC 50 : 2.31 ± 0.1, 3.40 ± 0.2, and 3.53 ± 0.2 µM, respectively) as determined by [ 3 H]-ketamine displacement assays. Finally, induction of AMPA receptors by either estrogens or ketamine and its metabolites was lost when ERα was knocked down or silenced pharmacologically. These results suggest a positive feedback loop by which estrogens can augment the effects of ketamine and its (2R,6R)-HNK and (2S,6S)-HNK metabolites on the ERα-induced transcription of CYP2A6 and CYP2B6, estrogen inducible enzymes that catalyze ketamine's biotransformation to form the two active metabolites. These observations provide novel insight into ketamine's molecular mechanism(s) of action and have potential implications for the treatment of MDD. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Tamoxifen regulation of bone growth and endocrine function in the ovariectomized rat: discrimination of responses involving estrogen receptor α/estrogen receptor β, G protein-coupled estrogen receptor, or estrogen-related receptor γ using fulvestrant (ICI 182780).

    PubMed

    Fitts, James M; Klein, Robert M; Powers, C Andrew

    2011-07-01

    Tamoxifen is a selective estrogen receptor (ER) modulator, but it is also a deactivating ligand for estrogen-related receptor-γ (ERRγ) and a full agonist for the G protein-coupled estrogen receptor (GPER). Fulvestrant is a selective ER down-regulator that lacks agonist effects on ERα/ERβ, is inactive on ERRγ, but acts as a full agonist on GPER. Fulvestrant effects on tamoxifen actions on uterine and somatic growth, bone, the growth hormone (GH)-insulin-like growth factor I (IGF-I) axis, and pituitary prolactin were analyzed to pharmacologically discriminate tamoxifen effects that may be mediated by ERα/ERβ versus ERRγ versus GPER. Ovariectomized rats received tamoxifen (0.6 mg/kg/daily) plus fulvestrant at 0, 3, 6, or 12 mg/kg/daily for 5 weeks; controls received vehicle or 6 mg/kg fulvestrant daily. Tamoxifen effects to increase uterine weight, decrease serum IGF-I, increase pituitary prolactin, and increase bone mineral density could be fully blocked by fulvestrant, indicating mediation by ERα/ERβ. Tamoxifen effects to decrease pituitary GH, tibia length, and body weight were only partially blocked by fulvestrant, indicating involvement of mechanisms unrelated to ERα/ERβ. Fulvestrant did not inhibit tamoxifen actions to reduce total pituitary protein, again indicating effects not mediated by ERα/ERβ. Tamoxifen actions to reduce serum GH were mimicked rather than inhibited by fulvestrant, pharmacological features consistent with GPER involvement. However, fulvestrant alone increased IGF-I and also blocked tamoxifen-evoked IGF-I decreases; thus fulvestrant effects on serum GH might reflect increased IGF-I feedback inhibition. Fulvestrant alone had no effect on the other parameters. The findings indicate that mechanisms unrelated to ERα/ERβ contribute to tamoxifen effects on body weight, bone growth, and pituitary function.

  8. Estrogen receptor (ESR1) mutation in bone metastases from breast cancer.

    PubMed

    Bartels, Stephan; Christgen, Matthias; Luft, Angelina; Persing, Sascha; Jödecke, Kai; Lehmann, Ulrich; Kreipe, Hans

    2018-01-01

    Activating mutations of estrogen receptor α gene (ESR1) in breast cancer can cause endocrine resistance of metastatic tumor cells. The skeleton belongs to the metastatic sides frequently affected by breast cancer. The prevalence of ESR1 mutation in bone metastasis and the corresponding phenotype are not known. In this study bone metastases from breast cancer (n=231) were analyzed for ESR1 mutation. In 27 patients (12%) (median age 73 years, range: 55-82 years) activating mutations of ESR1 were detected. The most frequent mutation was p.D538G (53%), no mutations in exon 4 (K303) or 7 (S463) were found. Lobular breast cancer was present in 52% of mutated cases (n=14) and in 49% of all samples (n=231), respectively. Mutated cancers constantly displayed strong estrogen receptor expression. Progesterone receptor was positive in 78% of the mutated cases (n=21). From 194 estrogen receptor-positive samples, 14% had ESR1 mutated. Except for one mutated case, no concurrent HER2 overexpression was noted. Metastatic breast cancer with activating mutations of ESR1 had a higher Ki67 labeling index than primary luminal cancers (median 30%, ranging from 5 to 60% with 85% of cases revealing ≥20% Ki67-positive cells). From those patients from whom information on endocrine therapy was available (n=7), two had received tamoxifen only, 4 tamoxifen followed by aromatase inhibitors and one patient had been treated with aromatase inhibitors only. We conclude that ESR1 mutation is associated with estrogen receptor expression and high proliferative activity and affects about 14% of estrogen receptor-positive bone metastases from breast cancer.

  9. Increased anxiety and synaptic plasticity in estrogen receptor -deficient mice

    NASA Astrophysics Data System (ADS)

    Krel, Wojciech; Dupont, Sonia; Krust, Andrée; Chambon, Pierre; Chapman, Paul F.

    2001-10-01

    Estrogens are powerful modulators of neuronal physiology and in humans may affect a broad range of functions, including reproductive, emotional, and cognitive behaviors. We studied the contribution of estrogen receptors (ERs) in modulation of emotional processes and analyzed the effects of deleting ER or ER in mice. Behavior consistent with increased anxiety was observed principally in ER mutant females and was associated with a reduced threshold for the induction of synaptic plasticity in the basolateral amygdala. Local increase of 5-hydroxytryptamine 1a receptor expression inmedial amygdala may contribute to these changes. Our data show that, particularly in females, there is an important role for ERβ-mediated estrogen signaling in the processing of emotional behavior.

  10. The estrogen-related receptors (ERRs): potential targets against bone loss.

    PubMed

    Zhang, Ling; Wong, Jiemin; Vanacker, Jean-Marc

    2016-10-01

    Bone loss and the resulting skeletal fragility is induced by several pathological or natural conditions, the most prominent of which being aging as well as the decreased levels of circulating estrogens in post-menopause females. To date, most treatments against bone loss aim at preventing excess bone resorption. We here summarize data indicating that the estrogen-related receptors (ERRs) α and γ prevent bone formation. Inhibiting these receptors may thus constitute an anabolic approach by increasing bone formation.

  11. Association of the membrane estrogen receptor, GPR30, with breast tumor metastasis and transactivation of the epidermal growth factor receptor.

    PubMed

    Filardo, Edward J; Quinn, Jeffrey A; Sabo, Edmond

    2008-10-01

    The epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases function as a common signaling conduit for membrane receptors that lack intrinsic enzymatic activity, such as G-protein coupled receptors and integrins. GPR30, an orphan member of the seven transmembrane receptor (7TMR) superfamily has been linked to specific estrogen binding, rapid estrogen-mediated activation of adenylyl cyclase and the release of membrane-tethered proHB-EGF. More recently, GPR30 expression in primary breast adenocarcinoma has been associated with pathological parameters commonly used to assess breast cancer progression, including the development of extramammary metastases. This newly appreciated mechanism of cross communication between estrogen and EGF is consistent with the observation that 7TMR-mediated transactivation of the EGFR is a recurrent signaling paradigm and may explain prior data reporting the EGF-like effects of estrogen. The molecular details surrounding GPR30-mediated release of proHB-EGF, the involvement of integrin beta1 as a signaling intermediary in estrogen-dependent EGFR action, and the possible implications of these data for breast cancer progression are discussed herein.

  12. Estrogen-related receptor α decreases RHOA stability to induce orientated cell migration

    PubMed Central

    Sailland, Juliette; Tribollet, Violaine; Forcet, Christelle; Billon, Cyrielle; Barenton, Bruno; Carnesecchi, Julie; Bachmann, Alice; Gauthier, Karine Cécile; Yu, Shan; Giguère, Vincent; Chan, Franky L.; Vanacker, Jean-Marc

    2014-01-01

    Several physiopathological processes require orientated cellular migration. This phenomenon highly depends on members of the RHO family of GTPases. Both excessive and deficient RHO activity impair directional migration. A tight control is thus exerted on these proteins through the regulation of their activation and of their stability. Here we show that the estrogen-related receptor α (ERRα) directly activates the expression of TNFAIP1, the product of which [BTB/POZ domain-containing adapter for Cullin3-mediated RhoA degradation 2 (BACURD2)] regulates RHOA protein turnover. Inactivation of the receptor leads to enhanced RHOA stability and activation. This results in cell disorientation, increased actin network, and inability to form a lamellipodium at the migration edge. As a consequence, directional migration, but not cell motility per se, is impaired in the absence of the receptor, under pathological as well as physiological conditions. Altogether, our results show that the control exerted by ERRα on RHOA stability is required for directional migration. PMID:25288732

  13. Estrogen-related receptor α decreases RHOA stability to induce orientated cell migration.

    PubMed

    Sailland, Juliette; Tribollet, Violaine; Forcet, Christelle; Billon, Cyrielle; Barenton, Bruno; Carnesecchi, Julie; Bachmann, Alice; Gauthier, Karine Cécile; Yu, Shan; Giguère, Vincent; Chan, Franky L; Vanacker, Jean-Marc

    2014-10-21

    Several physiopathological processes require orientated cellular migration. This phenomenon highly depends on members of the RHO family of GTPases. Both excessive and deficient RHO activity impair directional migration. A tight control is thus exerted on these proteins through the regulation of their activation and of their stability. Here we show that the estrogen-related receptor α (ERRα) directly activates the expression of TNFAIP1, the product of which [BTB/POZ domain-containing adapter for Cullin3-mediated RhoA degradation 2 (BACURD2)] regulates RHOA protein turnover. Inactivation of the receptor leads to enhanced RHOA stability and activation. This results in cell disorientation, increased actin network, and inability to form a lamellipodium at the migration edge. As a consequence, directional migration, but not cell motility per se, is impaired in the absence of the receptor, under pathological as well as physiological conditions. Altogether, our results show that the control exerted by ERRα on RHOA stability is required for directional migration.

  14. Epidermal growth factor induces G protein-coupled receptor 30 expression in estrogen receptor-negative breast cancer cells.

    PubMed

    Albanito, Lidia; Sisci, Diego; Aquila, Saveria; Brunelli, Elvira; Vivacqua, Adele; Madeo, Antonio; Lappano, Rosamaria; Pandey, Deo Prakash; Picard, Didier; Mauro, Loredana; Andò, Sebastiano; Maggiolini, Marcello

    2008-08-01

    Different cellular receptors mediate the biological effects induced by estrogens. In addition to the classical nuclear estrogen receptors (ERs)-alpha and -beta, estrogen also signals through the seven-transmembrane G-protein-coupled receptor (GPR)-30. Using as a model system SkBr3 and BT20 breast cancer cells lacking the classical ER, the regulation of GPR30 expression by 17beta-estradiol, the selective GPR30 ligand G-1, IGF-I, and epidermal growth factor (EGF) was evaluated. Transient transfections with an expression plasmid encoding a short 5'-flanking sequence of the GPR30 gene revealed that an activator protein-1 site located within this region is required for the activating potential exhibited only by EGF. Accordingly, EGF up-regulated GPR30 protein levels, which accumulated predominantly in the intracellular compartment. The stimulatory role elicited by EGF on GPR30 expression was triggered through rapid ERK phosphorylation and c-fos induction, which was strongly recruited to the activator protein-1 site found in the short 5'-flanking sequence of the GPR30 gene. Of note, EGF activating the EGF receptor-MAPK transduction pathway stimulated a regulatory loop that subsequently engaged estrogen through GPR30 to boost the proliferation of SkBr3 and BT20 breast tumor cells. The up-regulation of GPR30 by ligand-activated EGF receptor-MAPK signaling provides new insight into the well-known estrogen and EGF cross talk, which, as largely reported, contributes to breast cancer progression. On the basis of our results, the action of EGF may include the up-regulation of GPR30 in facilitating a stimulatory role of estrogen, even in ER-negative breast tumor cells.

  15. G Protein-Coupled Estrogen Receptor-Selective Ligands Modulate Endometrial Tumor Growth

    PubMed Central

    Petrie, Whitney K.; Dennis, Megan K.; Dai, Donghai; Arterburn, Jeffrey B.; Smith, Harriet O.; Hathaway, Helen J.; Prossnitz, Eric R.

    2013-01-01

    Endometrial carcinoma is the most common cancer of the female reproductive tract. GPER/GPR30 is a 7-transmembrane spanning G protein-coupled receptor that has been identified as the third estrogen receptor, in addition to ERα and ERβ. High GPER expression is predictive of poor survival in endometrial and ovarian cancer, but despite this, the estrogen-mediated signaling pathways and specific estrogen receptors involved in endometrial cancer remain unclear. Here, employing ERα-negative Hec50 endometrial cancer cells, we demonstrate that GPER mediates estrogen-stimulated activation of ERK and PI3K via matrix metalloproteinase activation and subsequent transactivation of the EGFR and that ER-targeted therapeutic agents (4-hydroxytamoxifen, ICI182,780/fulvestrant, and Raloxifene), the phytoestrogen genistein, and the “ERα-selective” agonist propylpyrazole triol also function as GPER agonists. Furthermore, xenograft tumors of Hec50 cells yield enhanced growth with G-1 and estrogen, the latter being inhibited by GPER-selective pharmacologic antagonism with G36. These results have important implications with respect to the use of putatively ER-selective ligands and particularly for the widespread long-term use of “ER-targeted” therapeutics. Moreover, our findings shed light on the potential mechanisms of SERM/SERD side effects reported in many clinical studies. Finally, our results provide the first demonstration that pharmacological inhibition of GPER activity in vivo prevents estrogen-mediated tumor growth. PMID:24379833

  16. G protein-coupled estrogen receptor-selective ligands modulate endometrial tumor growth.

    PubMed

    Petrie, Whitney K; Dennis, Megan K; Hu, Chelin; Dai, Donghai; Arterburn, Jeffrey B; Smith, Harriet O; Hathaway, Helen J; Prossnitz, Eric R

    2013-01-01

    Endometrial carcinoma is the most common cancer of the female reproductive tract. GPER/GPR30 is a 7-transmembrane spanning G protein-coupled receptor that has been identified as the third estrogen receptor, in addition to ERα and ERβ. High GPER expression is predictive of poor survival in endometrial and ovarian cancer, but despite this, the estrogen-mediated signaling pathways and specific estrogen receptors involved in endometrial cancer remain unclear. Here, employing ERα-negative Hec50 endometrial cancer cells, we demonstrate that GPER mediates estrogen-stimulated activation of ERK and PI3K via matrix metalloproteinase activation and subsequent transactivation of the EGFR and that ER-targeted therapeutic agents (4-hydroxytamoxifen, ICI182,780/fulvestrant, and Raloxifene), the phytoestrogen genistein, and the "ERα-selective" agonist propylpyrazole triol also function as GPER agonists. Furthermore, xenograft tumors of Hec50 cells yield enhanced growth with G-1 and estrogen, the latter being inhibited by GPER-selective pharmacologic antagonism with G36. These results have important implications with respect to the use of putatively ER-selective ligands and particularly for the widespread long-term use of "ER-targeted" therapeutics. Moreover, our findings shed light on the potential mechanisms of SERM/SERD side effects reported in many clinical studies. Finally, our results provide the first demonstration that pharmacological inhibition of GPER activity in vivo prevents estrogen-mediated tumor growth.

  17. Expression of estrogen, estrogen related and androgen receptors in adrenal cortex of intact adult male and female rats.

    PubMed

    Trejter, Marcin; Jopek, Karol; Celichowski, Piotr; Tyczewska, Marianna; Malendowicz, Ludwik K; Rucinski, Marcin

    2015-01-01

    Adrenocortical activity in various species is sensitive to androgens and estrogens. They may affect adrenal cortex growth and functioning either via central pathways (CRH and ACTH) or directly, via specific receptors expressed in the cortex and/or by interfering with adrenocortical enzymes, among them those involved in steroidogenesis. Only limited data on expression of androgen and estrogen receptors in adrenal glands are available. Therefore the present study aimed to characterize, at the level of mRNA, expression of these receptors in specific components of adrenal cortex of intact adult male and female rats. Studies were performed on adult male and female (estrus) Wistar rats. Total RNA was isolated from adrenal zona glomerulosa (ZG) and fasciculate/reticularis (ZF/R). Expression of genes were evaluated by means of Affymetrix® Rat Gene 1.1 ST Array Strip and QPCR. By means of Affymetrix® Rat Gene 1.1 ST Array we examined adrenocortical sex differences in the expression of nearly 30,000 genes. All data were analyzed in relation to the adrenals of the male rats. 32 genes were differentially expressed in ZG, and 233 genes in ZF/R. In the ZG expression levels of 24 genes were lower and 8 higher in female rats. The more distinct sex differences were observed in the ZF/R, in which expression levels of 146 genes were lower and 87 genes higher in female rats. Performed analyses did not reveal sex differences in the expression levels of both androgen (AR) and estrogen (ER) receptor genes in the adrenal cortex of male and female rats. Therefore matrix data were validated by QPCR. QPCR revealed higher expression levels of AR gene both in ZG and ZF/R of male than female rats. On the other hand, QPCR did not reveal sex-related differences in the expression levels of ERα, ERβ and non-genomic GPR30 (GPER-1) receptor. Of those genes expression levels of ERα genes were the highest. In studied adrenal samples the relative expression of ERα mRNA was higher than ERβ m

  18. International Union of Basic and Clinical Pharmacology. XCVII. G Protein–Coupled Estrogen Receptor and Its Pharmacologic Modulators

    PubMed Central

    2015-01-01

    Estrogens are critical mediators of multiple and diverse physiologic effects throughout the body in both sexes, including the reproductive, cardiovascular, endocrine, nervous, and immune systems. As such, alterations in estrogen function play important roles in many diseases and pathophysiological conditions (including cancer), exemplified by the lower prevalence of many diseases in premenopausal women. Estrogens mediate their effects through multiple cellular receptors, including the nuclear receptor family (ERα and ERβ) and the G protein–coupled receptor (GPCR) family (GPR30/G protein–coupled estrogen receptor [GPER]). Although both receptor families can initiate rapid cell signaling and transcriptional regulation, the nuclear receptors are traditionally associated with regulating gene expression, whereas GPCRs are recognized as mediating rapid cellular signaling. Estrogen-activated pathways are not only the target of multiple therapeutic agents (e.g., tamoxifen, fulvestrant, raloxifene, and aromatase inhibitors) but are also affected by a plethora of phyto- and xeno-estrogens (e.g., genistein, coumestrol, bisphenol A, dichlorodiphenyltrichloroethane). Because of the existence of multiple estrogen receptors with overlapping ligand specificities, expression patterns, and signaling pathways, the roles of the individual receptors with respect to the diverse array of endogenous and exogenous ligands have been challenging to ascertain. The identification of GPER-selective ligands however has led to a much greater understanding of the roles of this receptor in normal physiology and disease as well as its interactions with the classic estrogen receptors ERα and ERβ and their signaling pathways. In this review, we describe the history and characterization of GPER over the past 15 years focusing on the pharmacology of steroidal and nonsteroidal compounds that have been employed to unravel the biology of this most recently recognized estrogen receptor. PMID

  19. Effects of estrogen receptor modulators on cytoskeletal proteins in the central nervous system.

    PubMed

    Segura-Uribe, Julia J; Pinto-Almazán, Rodolfo; Coyoy-Salgado, Angélica; Fuentes-Venado, Claudia E; Guerra-Araiza, Christian

    2017-08-01

    Estrogen receptor modulators are compounds of interest because of their estrogenic agonistic/antagonistic effects and tissue specificity. These compounds have many clinical applications, particularly for breast cancer treatment and osteoporosis in postmenopausal women, as well as for the treatment of climacteric symptoms. Similar to estrogens, neuroprotective effects of estrogen receptor modulators have been described in different models. However, the mechanisms of action of these compounds in the central nervous system have not been fully described. We conducted a systematic search to investigate the effects of estrogen receptor modulators in the central nervous system, focusing on the modulation of cytoskeletal proteins. We found that raloxifene, tamoxifen, and tibolone modulate some cytoskeletal proteins such as tau, microtuble-associated protein 1 (MAP1), MAP2, neurofilament 38 (NF38) by different mechanisms of action and at different levels: neuronal microfilaments, intermediate filaments, and microtubule-associated proteins. Finally, we emphasize the importance of the study of these compounds in the treatment of neurodegenerative diseases since they present the benefits of estrogens without their side effects.

  20. Effects of estrogen receptor modulators on cytoskeletal proteins in the central nervous system

    PubMed Central

    Segura-Uribe, Julia J.; Pinto-Almazán, Rodolfo; Coyoy-Salgado, Angélica; Fuentes-Venado, Claudia E.; Guerra-Araiza, Christian

    2017-01-01

    Estrogen receptor modulators are compounds of interest because of their estrogenic agonistic/antagonistic effects and tissue specificity. These compounds have many clinical applications, particularly for breast cancer treatment and osteoporosis in postmenopausal women, as well as for the treatment of climacteric symptoms. Similar to estrogens, neuroprotective effects of estrogen receptor modulators have been described in different models. However, the mechanisms of action of these compounds in the central nervous system have not been fully described. We conducted a systematic search to investigate the effects of estrogen receptor modulators in the central nervous system, focusing on the modulation of cytoskeletal proteins. We found that raloxifene, tamoxifen, and tibolone modulate some cytoskeletal proteins such as tau, microtuble-associated protein 1 (MAP1), MAP2, neurofilament 38 (NF38) by different mechanisms of action and at different levels: neuronal microfilaments, intermediate filaments, and microtubule-associated proteins. Finally, we emphasize the importance of the study of these compounds in the treatment of neurodegenerative diseases since they present the benefits of estrogens without their side effects. PMID:28966632

  1. Aromatase and estrogen receptors in male reproduction.

    PubMed

    Carreau, Serge; Delalande, Christelle; Silandre, Dorothée; Bourguiba, Sonia; Lambard, Sophie

    2006-02-26

    Aromatase is a terminal enzyme which transforms irreversibly androgens into estrogens and it is present in the endoplasmic reticulum of numerous tissues. We have demonstrated that mature rat germ cells express a functional aromatase with a production of estrogens equivalent to that of Leydig cells. In humans in addition to Leydig cells, we have shown the presence of aromatase in ejaculated spermatozoa and in immature germ cells. In most tissues, high affinity estrogen receptors, ERalpha and/or ERbeta, mediate the role of estrogens. Indeed, in human spermatozoa, we have successfully amplified ERbeta mRNA but the protein was not detectable. Using ERalpha antibody we have detected two proteins in human immature germ cells: one at the expected size 66 kDa and another at 46 kDa likely corresponding to the ERalpha isoform lacking exon 1. In spermatozoa only the 46 kDa isoform was present, and we suggest that it may be located on the membrane. In addition, in men genetically deficient in aromatase, it is reported that alterations of spermatogenesis occur both in terms of the number and motility of spermatozoa. All together, these observations suggest that endogenous estrogens are important in male reproduction.

  2. Estrogen Receptor-α in the Medial Amygdala Prevents Stress-Induced Elevations in Blood Pressure in Females.

    PubMed

    Hinton, Antentor Othrell; He, Yanlin; Xia, Yan; Xu, Pingwen; Yang, Yongjie; Saito, Kenji; Wang, Chunmei; Yan, Xiaofeng; Shu, Gang; Henderson, Alexander; Clegg, Deborah J; Khan, Sohaib A; Reynolds, Corey; Wu, Qi; Tong, Qingchun; Xu, Yong

    2016-06-01

    Psychological stress contributes to the development of hypertension in humans. The ovarian hormone, estrogen, has been shown to prevent stress-induced pressor responses in females by unknown mechanisms. Here, we showed that the antihypertensive effects of estrogen during stress were blunted in female mice lacking estrogen receptor-α in the brain medial amygdala. Deletion of estrogen receptor-α in medial amygdala neurons also resulted in increased excitability of these neurons, associated with elevated ionotropic glutamate receptor expression. We further demonstrated that selective activation of medial amygdala neurons mimicked effects of stress to increase blood pressure in mice. Together, our results support a model where estrogen acts on estrogen receptor-α expressed by medial amygdala neurons to prevent stress-induced activation of these neurons, and therefore prevents pressor responses to stress. © 2016 American Heart Association, Inc.

  3. GPER - novel membrane estrogen receptor

    PubMed Central

    Zimmerman, Margaret A.; Budish, Rebecca A.; Kashyap, Shreya; Lindsey, Sarah H.

    2016-01-01

    The recent discovery of the G protein-coupled estrogen receptor (GPER) presents new challenges and opportunities for understanding the physiology, pathophysiology, and pharmacology of many diseases. This review will focus on the expression and function of GPER in hypertension, kidney disease, atherosclerosis, vascular remodeling, heart failure, reproduction, metabolic disorders, cancer, environmental health, and menopause. Furthermore, this review will highlight the potential of GPER as a therapeutic target. PMID:27154744

  4. Factors Modulating Estrogen Receptor Activity

    DTIC Science & Technology

    1997-07-01

    public release; distribution unlimited The views, opinions and/or findings contained in this report are those of the author( s ) and should not be...TITLE AND SUBTITLE Activity Factors Modulating Estrogen Receptor 6. AUTHOR( S ) Michael J. Garabedian, Ph.D. 7. PERFORMING ORGANIZATION NAME( S ) AND...ADDRESS(ES) New York University Medical Center New York, New York 10016 9. SPONSORING/MONITORING AGENCY NAME( S ) AND ADDRESS(ES) Commander U.S

  5. International Union of Basic and Clinical Pharmacology. XCVII. G Protein-Coupled Estrogen Receptor and Its Pharmacologic Modulators.

    PubMed

    Prossnitz, Eric R; Arterburn, Jeffrey B

    2015-07-01

    Estrogens are critical mediators of multiple and diverse physiologic effects throughout the body in both sexes, including the reproductive, cardiovascular, endocrine, nervous, and immune systems. As such, alterations in estrogen function play important roles in many diseases and pathophysiological conditions (including cancer), exemplified by the lower prevalence of many diseases in premenopausal women. Estrogens mediate their effects through multiple cellular receptors, including the nuclear receptor family (ERα and ERβ) and the G protein-coupled receptor (GPCR) family (GPR30/G protein-coupled estrogen receptor [GPER]). Although both receptor families can initiate rapid cell signaling and transcriptional regulation, the nuclear receptors are traditionally associated with regulating gene expression, whereas GPCRs are recognized as mediating rapid cellular signaling. Estrogen-activated pathways are not only the target of multiple therapeutic agents (e.g., tamoxifen, fulvestrant, raloxifene, and aromatase inhibitors) but are also affected by a plethora of phyto- and xeno-estrogens (e.g., genistein, coumestrol, bisphenol A, dichlorodiphenyltrichloroethane). Because of the existence of multiple estrogen receptors with overlapping ligand specificities, expression patterns, and signaling pathways, the roles of the individual receptors with respect to the diverse array of endogenous and exogenous ligands have been challenging to ascertain. The identification of GPER-selective ligands however has led to a much greater understanding of the roles of this receptor in normal physiology and disease as well as its interactions with the classic estrogen receptors ERα and ERβ and their signaling pathways. In this review, we describe the history and characterization of GPER over the past 15 years focusing on the pharmacology of steroidal and nonsteroidal compounds that have been employed to unravel the biology of this most recently recognized estrogen receptor. Copyright

  6. Novel drugs that target the estrogen-related receptor alpha: their therapeutic potential in breast cancer

    PubMed Central

    May, Felicity EB

    2014-01-01

    The incidence of breast cancer continues to rise: 1.7 million women were diagnosed with and 521,000 women died from breast cancer in 2012. This review considers first current treatment options: surgery; radiotherapy; and systemic endocrine, anti-biological, and cytotoxic therapies. Clinical management includes prevention, early detection by screening, treatment with curative intent, management of chronic disease, and palliative control of advanced breast cancer. Next, the potential of novel drugs that target DNA repair, growth factor dependence, intracellular and intercellular signal transduction, and cell cycle are considered. Estrogen-related receptor alpha has attracted attention as a therapeutic target in triple-negative breast cancers with de novo resistance to, and in breast cancers with acquired resistance to, endocrine therapies such as antiestrogens and aromatase inhibitors. Estrogen-related receptor alpha is an orphan receptor and transcription factor. Its activity is regulated by coregulator proteins and posttranslational modification. It is an energy sensor that controls adaptation to energy demand and may facilitate glycolytic metabolism and mitochondrial oxidative respiration in breast cancer cells. Estrogen-related receptor alpha increases breast cancer cell migration, proliferation, and tumor development. It is expressed at high levels in estrogen receptor-negative tumors, and is proposed to activate estrogen-responsive genes in endocrine-resistant tumors. The structures and functions of the ligand-binding domains of estrogen receptor alpha and estrogen-related receptor alpha, their ability to bind estrogens, phytoestrogens, and synthetic ligands, and the effects of ligand agonists, antagonists, and inverse agonists on biological activity, are evaluated. Synthetic ligands of estrogen-related receptor alpha have activity in preclinical models of metabolic disorders, diabetes, osteoporosis, and oncology. The clinical settings in which these novel

  7. Estrogen receptor expert system overview and examples

    EPA Science Inventory

    The estrogen receptor expert system (ERES) is a rule-based system developed to prioritize chemicals based upon their potential for binding to the ER. The ERES was initially developed to predict ER affinity of chemicals from two specific EPA chemical inventories, antimicrobial pe...

  8. Identification of the G protein-coupled estrogen receptor (GPER) in human prostate: expression site of the estrogen receptor in the benign and neoplastic gland.

    PubMed

    Rago, V; Romeo, F; Giordano, F; Ferraro, A; Carpino, A

    2016-01-01

    Estrogens are involved in growth, differentiation and pathogenesis of human prostate through the mediation of the classical estrogen receptors ERα and ERβ. The G protein-coupled estrogen receptor (GPER) is a 'novel' mediator of estrogen signaling which has been recently recognized in some human reproductive tissues, but its expression in the prostate gland is still unknown. Here, we investigated GPER in benign (from 5 patients) and neoplastic prostatic tissues (from 50 patients) by immunohistochemical analysis and Western blotting. Normal areas of benign prostates revealed a strong GPER immunoreactivity in the basal epithelial cells while luminal epithelial cells were unreactive and stromal cells were weakly immunostained. GPER was also immunolocalized in adenocarcinoma samples but the immunoreactivity of tumoral areas decreased from Gleason pattern 2 to Gleason pattern 4. Furthermore, a strong GPER immunostaining was also revealed in cells of pre-neoplastic lesions (high-grade prostatic intra-epithelial neoplasia). Western blot analysis of benign and tumor protein extracts showed the presence of a ~42 kDa band, consistent with the GPER molecular weight. An increase in both pAkt and p cAMP-response-binding protein (pCREB) levels was also observed in poorly differentiated PCa samples. Finally, this work identified GPER in the epithelial basal cells of benign human prostate, with a different localization with respect to the classical estrogen receptors. Furthermore, the expression of GPER in prostatic adenocarcinoma cells was also observed but with a modulation of the immunoreactivity according to tumor cell arrangements. © 2015 American Society of Andrology and European Academy of Andrology.

  9. INDUCTION OF MAMMARY GLAND DEVELOPMENT IN ESTROGEN RECEPTOR-ALPHA KNOCKOUT MICE

    EPA Science Inventory

    Mammary glands from the estrogen receptor knockout ( ERKO) mouse do not undergo ductal morphogenesis or alveolar development. Disrupted Er signaling may result in reduced estrogen-responsive gene products in the mammary gland or reduced mammotropic hormones that contribute t...

  10. Estrogen Receptors and Chronic Venous Disease.

    PubMed

    Serra, R; Gallelli, L; Perri, P; De Francesco, E M; Rigiracciolo, D C; Mastroroberto, P; Maggiolini, M; de Franciscis, S

    2016-07-01

    Chronic venous disease (CVD) is a common and relevant problem affecting Western people. The role of estrogens and their receptors in the venous wall seems to support the major prevalence of CVD in women. The effects of the estrogens are mediated by three estrogen receptors (ERs): ERα, ERβ, and G protein-coupled ER (GPER). The expression of ERs in the vessel walls of varicose veins is evaluated. In this prospective study, patients of both sexes, with CVD and varicose veins undergoing open venous surgery procedures, were enrolled in order to obtain vein samples. To obtain control samples of healthy veins, patients of both sexes without CVD undergoing coronary artery bypass grafting with autologous saphenous vein were recruited (control group). Samples were processed in order to evaluate gene expression. Forty patients with CVD (10 men [25%], 30 women [75%], mean age 54.3 years [median 52 years, range 33-74 years]) were enrolled. Five patients without CVD (three men, two women [aged 61-73 years]) were enrolled as the control group. A significant increase of tissue expression of ERα, ERβ and GPER in patients with CVD was recorded (p < .01), which was also related to the severity of venous disease. ERs seem to play a role in CVD; in this study, the expression of ERs correlated with the severity of the disease, and their expression was correlated with the clinical stage. Copyright © 2016 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  11. G Protein-Coupled Estrogen Receptor in Energy Homeostasis and Obesity Pathogenesis

    PubMed Central

    Shi, Haifei; Dharshan Senthil Kumar, Shiva Priya; Liu, Xian

    2013-01-01

    Obesity and its related metabolic diseases have reached a pandemic level worldwide. There are sex differences in the prevalence of obesity and its related metabolic diseases, with men being more vulnerable than women; however, the prevalence of these disorders increases dramatically in women after menopause, suggesting that sex steroid hormone estrogens play key protective roles against development of obesity and metabolic diseases. Estrogens are important regulators of several aspects of metabolism, including body weight and body fat, caloric intake and energy expenditure, and glucose and lipid metabolism in both males and females. Estrogens act in complex ways on their nuclear estrogen receptors (ERs) ERα and ERβ and transmembrane ERs such as G protein-coupled estrogen receptor. Genetic tools, such as different lines of knockout mouse models, and pharmacological agents, such as selective agonists and antagonists, are available to study function and signaling mechanisms of ERs. We provide an overview of the evidence for the physiological and cellular actions of ERs in estrogen-dependent processes in the context of energy homeostasis and body fat regulation and discuss its pathology that leads to obesity and related metabolic states. PMID:23317786

  12. Endoxifen, 4-Hydroxytamoxifen and an Estrogenic Derivative Modulate Estrogen Receptor Complex Mediated Apoptosis in Breast Cancer.

    PubMed

    Maximov, Philipp Y; Abderrahman, Balkees; Fanning, Sean W; Sengupta, Surojeet; Fan, Ping; Curpan, Ramona F; Quintana Rincon, Daniela Maria; Greenland, Jeffery A; Rajan, Shyamala S; Greene, Geoffrey L; Jordan, V Craig

    2018-05-08

    Estrogen therapy was used to treat advanced breast cancer in postmenopausal women for decades until the introduction of tamoxifen. Resistance to long-term estrogen deprivation (LTED) with tamoxifen and aromatase inhibitors used as a treatment for breast cancer inevitably occurs, but unexpectedly low dose estrogen can cause regression of breast cancer and increase disease free survival in some patients. This therapeutic effect is attributed to estrogen-induced apoptosis in LTED breast cancer. Here we describe modulation of the estrogen receptor liganded with antiestrogens (endoxifen, 4-hydroxytamoxifen) and an estrogenic triphenylethylene (TPE) EthoxyTPE (EtOXTPE) on estrogen-induced apoptosis in LTED breast cancer cells. Our results show that the angular TPE estrogen (EtOXTPE) is able to induce the ER-mediated apoptosis only at a later time compared to planar estradiol in these cells. Using RT-PCR, ChIP, Western blotting, molecular modelling and X-ray crystallography techniques we report novel conformations of the ER complex with an angular estrogen EtOXTPE and endoxifen. We propose that alteration of the conformation of the ER complexes, with changes in coactivator binding, governs estrogen-induced apoptosis through the PERK sensor system to trigger an Unfolded Protein Response (UPR). The American Society for Pharmacology and Experimental Therapeutics.

  13. Estrogen via estrogen receptor beta partially inhibits mandibular condylar cartilage growth.

    PubMed

    Chen, J; Kamiya, Y; Polur, I; Xu, M; Choi, T; Kalajzic, Z; Drissi, H; Wadhwa, S

    2014-11-01

    Temporomandibular joint (TMJ) diseases predominantly afflict women, suggesting a role for female hormones in the disease process. However, little is known about the role of estrogen receptor (ER) signaling in regulating mandibular condylar cartilage growth. Therefore, the goal of this study was to examine the effects of altered estrogen levels on the mandibular condylar cartilage in wild type (WT) and ER beta Knockout (KO) mice. 21-day-old female WT (n = 37) and ER beta KO mice (n = 36) were either sham operated or ovariectomized, and treated with either placebo or estradiol. The mandibular condylar cartilage was evaluated by histomorphometry, proliferation was analyzed by double ethynyl-2'-deoxyuridine/bromodeoxyuridine (EdU/BrdU) labeling, and assays on gene and protein expression of chondrocyte maturation markers were performed. In WT mice, ovariectomy caused a significant increase in mandibular condylar cartilage cell numbers, a significant increase in Sox9 expression and a significant increase in proliferation compared with sham operated WT mice. In contrast, ovariectomy did not cause any of these effects in the ER beta KO mice. Estrogen replacement treatment in ovariectomized WT mice caused a significant decrease in ER alpha expression and a significant increase in Sost expression compared with ovariectomized mice treated with placebo. Estrogen replacement treatment in ovariectomized ER beta KO mice caused a significant increase in Col2 expression, no change in ER alpha expression, and a significant increase in Sost expression. Estrogen via ER beta inhibits proliferation and ER alpha expression while estrogen independent of ER beta induces Col2 and Sost expression. Copyright © 2014 China University of Geosciences (Beijing) and Peking University. Published by Elsevier Ltd. All rights reserved.

  14. Antiestrogenic activity of flavnoid phytochemicals mediated via c-Jun N-terminal protein kinase pathway. Cell-type specific regulation of estrogen receptor alpha

    USDA-ARS?s Scientific Manuscript database

    Flavonoid phytochemicals act as both agonists and antagonists of the human estrogen receptors (ERs). While a number of these compounds act by directly binding to the ER, certain phytochemicals, such as the flavonoid compounds chalcone and flavone, elicit antagonistic effects on estrogen signaling in...

  15. Expression and localization of aromatase P450AROM, estrogen receptor-α, and estrogen receptor-β in the developing fetal bovine frontal cortex.

    PubMed

    Peruffo, A; Giacomello, M; Montelli, S; Corain, L; Cozzi, B

    2011-06-01

    The enzyme aromatase (P450(AROM)) converts testosterone (T) into 17-β estradiol (E(2)) and is crucial for the control of development of the central nervous system during ontogenesis. The effects of E(2) in various brain areas are mediated by the estrogen receptor alpha (ER-α) and the estrogen receptor beta (ER-β). During fetal development, steroids are responsible for the sexual differentiation of the hypothalamus. Estrogens are also able to exert effects in other brain areas of the fetus including the frontal cortex, where they act through estrogen receptors (ERs) modulating cognitive function and affective behaviors. In this study we have determined the expression profiles of P450(AROM) and ERs in the fetal bovine frontal cortex by quantitative Real-Time PCR (qRT-PCR) throughout the prenatal development. The data show that the patterns of expression of both ERs are strongly correlated during pregnancy and increase in the last stage of gestation. On the contrary, the expression of P450(AROM) has no correlation with ERs expression and is not developmentally regulated. Moreover, we performed immunochemical studies showing that fetal neurons express P450(AROM) and the ERs. P450(AROM) is localized in the cytoplasm and only seldom present in the fine extensions of the cells; ER-α is detected predominantly in the soma whereas ER-β is only present in the nucleus of a few cells. This study provides new data on the development of the frontal cortex in a long gestation mammal with a large convoluted brain. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Selective estrogen receptor modulators and risk for coronary heart disease.

    PubMed

    Cano, A; Hermenegildo, C; Oviedo, P; Tarín, J J

    2007-04-01

    Coronary heart disease (CHD) is the leading cause of death in women in most countries. Atherosclerosis is the main biological process determining CHD. Clinical data support the notion that CHD is sensitive to estrogens, but debate exists concerning the effects of the hormone on atherosclerosis and its complications. Selective estrogen receptor modulators (SERMs) are compounds capable of binding the estrogen receptor to induce a functional profile distinct from estrogens. The possibility that SERMs may shift the estrogenic balance on cardiovascular risk towards a more beneficial profile has generated interest in recent years. There is considerable information on the effects of SERMs on distinct areas that are crucial in atherogenesis. The complexity derived from the diversity of variables affecting their mechanism of action plus the differences between compounds make it difficult to delineate one uniform trend for SERMs. The present picture, nonetheless, is one where SERMs seem less powerful than estrogens in atherosclerosis protection, but more gentle with advanced forms of the disease. The recent publication of the Raloxifene Use for The Heart (RUTH) study has confirmed a neutral effect for raloxifene. Prothrombotic states may favor occlusive thrombi at sites occupied by atheromatous plaques. Platelet activation has received attention as an important determinant of arterial thrombogenesis. Although still sparse, available evidence globally suggests neutral or beneficial effects for SERMs.

  17. Identifying a Mechanism for Crosstalk Between the Estrogen and Glucocorticoid Receptors | Center for Cancer Research

    Cancer.gov

    Estrogen has long been known to play important roles in the development and progression of breast cancer. Its receptor (ER), a member of the steroid receptor family, binds to estrogen response elements (EREs) in DNA and regulates gene transcription. More recently, another steroid receptor family member, the glucocorticoid receptor (GR), has been implicated in breast cancer

  18. Structural Stereochemistry of Androstene Hormones Determines Interactions with Human Androgen, Estrogen, and Glucocorticoid Receptors

    PubMed Central

    Shaak, Thomas L.; Wijesinghe, Dayanjan S.; Chalfant, Charles E.; Diegelmann, Robert F.; Ward, Kevin R.; Loria, Roger M.

    2013-01-01

    DHEA, 17α-AED, 17β-AED, and 17β-AET exhibit strong biological activity that has been attributed to androgenic, estrogenic, or antiglucocorticoid activity in vivo and in vitro. This study compared DHEA, 17α-AED, 17β-AED, and 17β-AET for their ability to activate the human AR, ER, and GR and determine the relative androgenicity, estrogenicity, and glucocorticoid activity. The results show that, at the receptor level, these androstene hormones are weak AR and even weaker ER activators. Direct androstene hormone activation of the human AR, ERα, and ERβ may not be essential for their biological function. Similarly, these hormones indirectly activated the human GR, only in the presence of high dexamethasone concentrations. These results underscore the major difference between androstene hormone interactions with these nuclear receptors and their biological effects. PMID:24729874

  19. Estrogen receptor 1 modulates circadian rhythms in adult female mice.

    PubMed

    Blattner, Margaret S; Mahoney, Megan M

    2014-06-01

    Estradiol influences the level and distribution of daily activity, the duration of the free-running period, and the behavioral phase response to light pulses. However, the mechanisms by which estradiol regulates daily and circadian rhythms are not fully understood. We tested the hypothesis that estrogens modulate daily activity patterns via both classical and "non-classical" actions at the estrogen receptor subtype 1 (ESR1). We used female transgenic mice with mutations in their estrogen response pathways; ESR1 knock-out (ERKO) mice and "non-classical" estrogen receptor knock-in (NERKI) mice. NERKI mice have an ESR1 receptor with a mutation in the estrogen-response-element binding domain, allowing only actions via "non-classical" genomic and second messenger pathways. Ovariectomized female NERKI, ERKO, and wildtype (WT) mice were given a subcutaneous capsule with low- or high-dose estradiol and compared with counterparts with no hormone replacement. We measured wheel-running activity in a light:dark cycle and constant darkness, and the behavioral phase response to light pulses given at different points during the subjective day and night. Estradiol increased average daily wheel-running, consolidated activity to the dark phase, and shortened the endogenous period in WT, but not NERKI and ERKO mice. The timing of activity onset during entrainment was advanced in all estradiol-treated animals regardless of genotype suggesting an ESR1-independent mechanism. We propose that estradiol modifies period, activity level, and distribution of activity via classical actions of ESR1 whereas an ESR1 independent mechanism regulates the phase of rhythms.

  20. The Molecular, Cellular and Clinical Consequences of Targeting the Estrogen Receptor Following Estrogen Deprivation Therapy

    PubMed Central

    Fan, Ping; Maximov, Philipp Y.; Curpan, Ramona F.; Abderrahman, Balkees; Jordan, V. Craig

    2015-01-01

    During the past twenty years our understanding of the control of breast tumor development, growth and survival has changed dramatically. The once long forgotten application of high dose synthetic estrogen therapy as the first chemical therapy to treat any cancer has been resurrected, refined and reinvented as the new biology of estrogen-induced apoptosis. High dose estrogen therapy was cast aside once tamoxifen, from its origins as a failed “morning after pill”, was reinvented as the first targeted therapy to treat any cancer. The current understanding of the mechanism of estrogen-induced apoptosis is described as a consequence of acquired resistance to long term antihormone therapy in estrogen receptor (ER) positive breast cancer. The ER signal transduction pathway remains a target for therapy in breast cancer despite “antiestrogen” resistance, but becomes a regulator of resistance. Multiple mechanisms of resistance come into play: Selective ER Modulator (SERM) stimulated growth, growth factor/ER crosstalk, estrogen-induced apoptosis and mutations of ER. But it is with the science of estrogen-induced apoptosis that the next innovation in women’s health will be developed. Recent evidence suggests that the glucocorticoid properties of medroxyprogesterone acetate blunt estrogen-induced apoptosis in estrogen deprived breast cancer cell populations. As a result breast cancer develops during long-term Hormone Replacement Therapy (HRT). A new synthetic progestin with estrogen-like properties, such as the 19 nortestosterone derivatives used in oral contraceptives, will continue to protect the uterus from unopposed estrogen stimulation but at the same time, reinforce apoptosis in vulnerable populations of nascent breast cancer cells. PMID:26052034

  1. Effects of environmental estrogenic chemicals on AP1 mediated transcription with estrogen receptors alpha and beta.

    PubMed

    Fujimoto, Nariaki; Honda, Hiroaki; Kitamura, Shigeyuki

    2004-01-01

    There has been much discussion concerning endocrine disrupting chemicals suspected of exerting adverse effects in both wildlife and humans. Since the majority of these compounds are estrogenic, a large number of in vitro tests for estrogenic characteristics have been developed for screening purpose. One reliable and widely used method is the reporter gene assay employing estrogen receptors (ERs) and a reporter gene with a cis-acting estrogen responsive element (ERE). Other elements such as AP1 also mediate estrogenic signals and the manner of response could be quite different from that of ERE. Since this has yet to be explored, the ER mediated AP1 activity in response to a series of environmental estrogens was investigated in comparison with ERE findings. All the compounds exhibited estrogenic properties with ERE-luc and their AP1 responses were quite similar. These was one exception, however, p,p'-DDT (1,1,1,-trichloro-2,2-bis(p-chlorophenyl)ethane) did not exert any AP1-luc activity, while it appeared to be estrogenic at 10(-7) to 10(-5)M with the ERE action. None of the compounds demonstrated ER beta:AP1 activity. These data suggest that significant differences can occur in responses through the two estrogen pathways depending on environmental chemicals.

  2. Estradiol induces endothelial cell migration and proliferation through estrogen receptor-enhanced RhoA/ROCK pathway.

    PubMed

    Oviedo, Pilar J; Sobrino, Agua; Laguna-Fernandez, Andrés; Novella, Susana; Tarín, Juan J; García-Pérez, Miguel-Angel; Sanchís, Juan; Cano, Antonio; Hermenegildo, Carlos

    2011-03-30

    Migration and proliferation of endothelial cells are involved in re-endothelialization and angiogenesis, two important cardiovascular processes that are increased in response to estrogens. RhoA, a small GTPase which controls multiple cellular processes, is involved in the control of cell migration and proliferation. Our aim was to study the role of RhoA on estradiol-induced migration and proliferation and its dependence on estrogen receptors activity. Human umbilical vein endothelial cells were stimulated with estradiol, in the presence or absence of ICI 182780 (estrogen receptors antagonist) and Y-27632 (Rho kinase inhibitor). Estradiol increased Rho GEF-1 gene expression and RhoA (gene and protein expression and activity) in an estrogen receptor-dependent manner. Cell migration, stress fiber formation and cell proliferation were increased in response to estradiol and were also dependent on the estrogen receptors and RhoA activation. Estradiol decreased p27 levels, and significantly raised the expression of cyclins and CDK. These effects were counteracted by the use of either ICI 182780 or Y-27632. In conclusion, estradiol enhances the RhoA/ROCK pathway and increases cell cycle-related protein expression by acting through estrogen receptors. This results in an enhanced migration and proliferation of endothelial cells. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  3. CITED2 modulates estrogen receptor transcriptional activity in breast cancer cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lau, Wen Min; Doucet, Michele; Huang, David

    2013-07-26

    Highlights: •The effects of elevated CITED2 on ER function in breast cancer cells are examined. •CITED2 enhances cell growth in the absence of estrogen and presence of tamoxifen. •CITED2 functions as a transcriptional co-activator of ER in breast cancer cells. -- Abstract: Cbp/p300-interacting transactivator with Glu/Asp-rich carboxy-terminal domain 2 (CITED2) is a member of the CITED family of non-DNA binding transcriptional co-activators of the p300/CBP-mediated transcription complex. Previously, we identified CITED2 as being overexpressed in human breast tumors relative to normal mammary epithelium. Upon further investigation within the estrogen receptor (ER)-positive subset of these breast tumor samples, we found thatmore » CITED2 mRNA expression was elevated in those associated with poor survival. In light of this observation, we investigated the effect of elevated CITED2 levels on ER function. While ectopic overexpression of CITED2 in three ER-positive breast cancer cell lines (MCF-7, T47D, and CAMA-1) did not alter cell proliferation in complete media, growth was markedly enhanced in the absence of exogenous estrogen. Correspondingly, cells overexpressing CITED2 demonstrated reduced sensitivity to the growth inhibitory effects of the selective estrogen receptor modulator, 4-hydroxytamoxifen. Subsequent studies revealed that basal ER transcriptional activity was elevated in CITED2-overexpressing cells and was further increased upon the addition of estrogen. Similarly, basal and estrogen-induced expression of the ER-regulated genes trefoil factor 1 (TFF1) and progesterone receptor (PGR) was higher in cells overexpressing CITED2. Concordant with this observation, ChIP analysis revealed higher basal levels of CITED2 localized to the TFF-1 and PGR promoters in cells with ectopic overexpression of CITED2, and these levels were elevated further in response to estrogen stimulation. Taken together, these data indicate that CITED2 functions as a

  4. Localization of androgen receptors and estrogen receptors in the same cells of the songbird brain.

    PubMed Central

    Gahr, M

    1990-01-01

    Estrogens and androgens each have unique effects but act together for the neural differentiation and control of sexual behaviors in male vertebrates, such as the canary. The neuronal basis for these synergistic effects is elusive because the spatial relation between estrogen target cells and androgen target cells is unknown. This study localized estrogen receptor (ER)-containing cells by using immunocytochemistry and androgen receptor (AR)-containing cells by using autoradiography in the same sections of the male canary brain. Three cell types, those containing only ER, those containing only AR, and those containing both ER and AR, were found in tissue-specific frequencies. The midbrain nucleus intercollicularis exhibited the highest number of cells expressing both ER and AR, whereas ER and AR are expressed only in disjunctive cell populations in the forebrain nucleus hyperstriatalis ventrale, pars caudale. Synergistic effects of androgens and estrogens for the neural behavorial control could result from cells containing both ER and AR (intracellular) and from neural circuits containing ER and AR in different cells (intercellular). Images PMID:2251286

  5. Integral assessment of estrogenic potentials in sediment-associated samples: Part 2: Study of estrogen and anti-estrogen receptor-binding potentials of sediment-associated chemicals under different salinity conditions using the salinity-adapted enzyme-linked receptor assay.

    PubMed

    Kase, Robert; Hansen, Peter D; Fischer, Birgit; Manz, Werner; Heininger, Peter; Reifferscheid, Georg

    2009-01-01

    sediments were tested in a dilution series to evaluate at which dilution step the receptor-binding potential ends. In the elution process (see Section 2.1 to 2.2), a method was developed to adjust the salinity to the levels of the reference testings, which offers an appropriate option to adjust the salinity in both directions. Statistical evaluation was made with a combination of the Mann-Whitney U test and the pT-method. This part of the study characterised the environmental factor 'salinity' for prospective applications of the ELRA. Using reference substances such as 17-beta-estradiol, the ELRA showed sigmoid concentration-effect relations over a broad range from 0.05 mug/l to 100 mug/l under physiological conditions. After methodological optimisation, both sensitivity and tolerance of the assay against salinity could be significantly raised, and the ELRA became applicable under salinity conditions up to concentrations of 20.5 per thousand. The mean relative inter-test error (n = 3) was around 11% with reference substances and below 5% for single sediments elutriates in three replicates each. For sediment testings, the pore water and different salinity-adjusted elutriates of 13 sediments were used. A clear differentiation of the receptor-binding potential could be reached by application of the pT-method. Thereby, pT-values from one to six could be assigned to the sediments, and the deviation caused by the different salinity conditions was one pT-value. The mean standard deviation in the salinity adaptation procedure of the elutriates was below 5%. Although the ELRA has already been used for assessments of wastewater, sludge and soil, its applicability for samples to different salinity levels has not been investigated so far. Even if the ELRA is not as sensitive as the E-screen or the YES-assay, with regard to reference substances like 17-beta-estradiol, it is a very useful tool for pre-screening, because it is able to integrate both estrogenic as well as anti-estrogenic

  6. Substrate Induced Conformational Studies of the Hormone Binding Domain of the Human Estrogen Receptor by Fluorine NMR

    DTIC Science & Technology

    1998-07-01

    the progression of breast cancer and the estrogen receptor (ER) has been implicated in reproductive cancers . Our laboratory would like to understand how...function. ൖ. SUBJECT TERMS 15. NUMBER OF PAGES Breast Cancer 41 16. PRICE CODE 17. SECURITY CLASSIFICATION 18. SECURITY CLASSIFICATION OF THIS 19...production of estrogen or estrogen like materials. Estrogen has been shown to be involved in the progression of breast cancer and the estrogen receptor (ER

  7. The role of selective estrogen receptor modulators in the treatment of schizophrenia.

    PubMed

    Bratek, Agnieszka; Krysta, Krzysztof; Drzyzga, Karolina; Barańska, Justyna; Kucia, Krzysztof

    2016-09-01

    Gender differences in schizophrenia have been recognized for a long time and it has been widely accepted that sex steroid hormones, especially estradiol, are strongly attributed to this fact. Two hypotheses regarding estradiol action in psychoses gained special research attention - the estrogen protection hypothesis and hypoestrogenism hypothesis. A growing number of studies have shown benefits in augmenting antipsychotic treatment with estrogens or selective estrogen receptor modulators (SERM). This review is focused on the role of selective estrogen receptor modulators in the treatment of schizophrenic patients. In order to achieve this result PubMed was searched using the following terms: schizophrenia, raloxifene, humans. We reviewed only randomized, placebo-controlled studies. Raloxifene, a selective estrogen receptor modulator was identified as useful to improve negative, positive, and general psychopathological symptoms, and also cognitive functions. All reviewed studies indicated improvement in at least one studied domain. Augmentation with raloxifene was found to be a beneficial treatment strategy for chronic schizophrenia both in female and male patients, however potential side effects (a small increase in the risk of venous thromboembolism and endometrial cancer) should be carefully considered. SERMs could be an effective augmentation strategy in the treatment of both men women with schizophrenia, although further research efforts are needed to study potential long-term side effects.

  8. Presence of estrogen receptors in human myeloid monocytic cells (THP-1 cell line).

    PubMed

    Cutolo, M; Villaggio, B; Bisso, A; Sulli, A; Coviello, D; Dayer, J M

    2001-01-01

    To test THP-1 cells for the presence of estrogen receptors (ER) since studies have demonstrated in vivo and in vitro, the influence of estrogens on cells involved in immune response (i.e. macrophages), and since it has been demonstrated that human myeloid monocytic THP-1 cells acquire phenotypic and functional macrophage-like features after incubation with several cytokines or pharmacological agents. Stimulation of THP-1 cells with phorbol myristate acetate (PMA) to prompt their differentiation into macrophage-like cells and evaluation of the possible induction of ER. The expression of ER was analyzed by immunocytochemical assay, reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot analysis. After stimulation by PMA, the human myeloid monocytic THP-1 cells showed the presence of ER, together with markers of monocytic cell differentiation such as CD68, CD54 and HLA-DR. Estrogen effects may be exerted directly through ER on monocytes/macrophages. PMA-treated THP-1 cells may constitute a useful in vitro model to determine the effects of estrogens on macrophage-like cells and their implications in the inflammatory and immune processes.

  9. CoMSIA and Docking Study of Rhenium Based Estrogen Receptor Ligand Analogs

    PubMed Central

    Wolohan, Peter; Reichert, David E.

    2007-01-01

    OPLS all atom force field parameters were developed in order to model a diverse set of novel rhenium based estrogen receptor ligands whose relative binding affinities (RBA) to the estrogen receptor alpha isoform (ERα) with respect to 17β-Estradiol were available. The binding properties of these novel rhenium based organometallic complexes were studied with a combination of Comparative Molecular Similarity Indices Analysis (CoMSIA) and docking. A total of 29 estrogen receptor ligands consisting of 11 rhenium complexes and 18 organic ligands were docked inside the ligand-binding domain (LBD) of ERα utilizing the program Gold. The top ranked pose was used to construct CoMSIA models from a training set of 22 of the estrogen receptor ligands which were selected at random. In addition scoring functions from the docking runs and the polar volume (PV) were also studied to investigate their ability to predict RBA ERα. A partial least-squares analysis consisting of the CoMSIA steric, electrostatic and hydrophobic indices together with the polar volume proved sufficiently predictive having a correlation coefficient, r2, of 0.94 and a cross-validated correlation coefficient, q2, utilizing the leave one out method of 0.68. Analysis of the scoring functions from Gold showed particularly poor correlation to RBA ERα which did not improve when the rhenium complexes were extracted to leave the organic ligands. The combined CoMSIA and polar volume model ranked correctly the ligands in order of increasing RBA ERα, illustrating the utility of this method as a prescreening tool in the development of novel rhenium based estrogen receptor ligands. PMID:17280694

  10. Relaxant Effects of the Selective Estrogen Receptor Modulator, Bazedoxifene, and Estrogen Receptor Agonists in Isolated Rabbit Basilar Artery.

    PubMed

    Castelló-Ruiz, María; Salom, Juan B; Fernández-Musoles, Ricardo; Burguete, María C; López-Morales, Mikahela A; Arduini, Alessandro; Jover-Mengual, Teresa; Hervás, David; Torregrosa, Germán; Alborch, Enrique

    2016-10-01

    We have previously shown that the selective estrogen receptor modulator, bazedoxifene, improves the consequences of ischemic stroke. Now we aimed to characterize the effects and mechanisms of action of bazedoxifene in cerebral arteries. Male rabbit isolated basilar arteries were used for isometric tension recording and quantitative polymerase chain reaction. Bazedoxifene relaxed cerebral arteries, as 17-β-estradiol, 4,4',4″-(4-propyl-[1H]-pyrazole-1,3,5-triyl)trisphenol [estrogen receptor (ER) α agonist], and G1 [G protein-coupled ER (GPER) agonist] did it (4,4',4″-(4-propyl-[1H]-pyrazole-1,3,5-triyl)trisphenol > bazedoxifene = G1 > 17-β-estradiol). 2,3-Bis(4-hydroxyphenyl)-propionitrile (ERβ agonist) had no effect. Expression profile of genes encoding for ERα (ESR1), ERβ (ESR2), and GPER was GPER > ESR1 > ESR2. As to the endothelial mechanisms, endothelium removal, N-nitro-L-arginine methyl ester, and indomethacin, did not modify the relaxant responses to bazedoxifene. As to the K channels, both a high-K medium and the Kv blocker, 4-aminopyridine, inhibited the bazedoxifene-induced relaxations, whereas tetraethylammonium (nonselective K channel blocker), glibenclamide (selective KATP blocker) or iberiotoxin (selective KCa blocker) were without effect. Bazedoxifene also inhibited both Ca- and Bay K8644-elicited contractions. Therefore, bazedoxifene induces endothelium-independent relaxations of cerebral arteries through (1) activation of GPER and ERα receptors; (2) increase of K conductance through Kv channels; and (3) inhibition of Ca entry through L-type Ca channels. Such a profile is compatible with the beneficial effects of estrogenic compounds (eg, SERMs) on vascular function and, specifically, that concerning the brain. Therefore, bazedoxifene could be useful in the treatment of cerebral disorders in which the cerebrovascular function is compromised (eg, stroke).

  11. Selectivity of natural, synthetic and environmental estrogens for zebrafish estrogen receptors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pinto, Caroline; Grimaldi, Marina; Boulahtouf, Abdelhay

    2014-10-01

    Zebrafish, Danio rerio, is increasingly used as an animal model to study the effects of pharmaceuticals and environmental estrogens. As most of these estrogens have only been tested on human estrogen receptors (ERs), it is necessary to measure their effects on zebrafish ERs. In humans there are two distinct nuclear ERs (hERα and hERβ), whereas the zebrafish genome encodes three ERs, zfERα and two zfERβs (zfERβ1 and zfERβ2). In this study, we established HeLa-based reporter cell lines stably expressing each of the three zfERs. We first reported that estrogens more efficiently activate the zfERs at 28 °C as compared tomore » 37 °C, thus reflecting the physiological temperature of zebrafish in wildlife. We then showed significant differences in the ability of agonist and antagonist estrogens to modulate activation of the three zfER isotypes in comparison to hERs. Environmental compounds (bisphenol A, alkylphenols, mycoestrogens) which are hER panagonists and hERβ selective agonists displayed greater potency for zfERα as compared to zfERβs. Among hERα selective synthetic agonists, PPT did not activate zfERα while 16α-LE2 was the most zfERα selective compound. Altogether, these results confirm that all hER ligands control in a similar manner the transcriptional activity of zfERs although significant differences in selectivity were observed among subtypes. The zfER subtype selective ligands that we identified thus represent new valuable tools to dissect the physiological roles of the different zfERs. Finally, our work also points out that care has to be taken in transposing the results obtained using the zebrafish as a model for human physiopathology. - Highlights: • Zebrafish is increasingly used to study the effects of estrogens. • We assessed the activity of pharmaceutical and environmental estrogens on zfERs. • Environmental estrogens displayed greater potency for zfERα compared to zfERβs. • hERβ selective agonists displayed greater

  12. Modulating Estrogen Receptor-related Receptor-α Activity Inhibits Cell Proliferation*

    PubMed Central

    Bianco, Stéphanie; Lanvin, Olivia; Tribollet, Violaine; Macari, Claire; North, Sophie; Vanacker, Jean-Marc

    2009-01-01

    High expression of the estrogen receptor-related receptor (ERR)-α in human tumors is correlated to a poor prognosis, suggesting an involvement of the receptor in cell proliferation. In this study, we show that a synthetic compound (XCT790) that modulates the activity of ERRα reduces the proliferation of various cell lines and blocks the G1/S transition of the cell cycle in an ERRα-dependent manner. XCT790 induces, in a p53-independent manner, the expression of the cell cycle inhibitor p21waf/cip1 at the protein, mRNA, and promoter level, leading to an accumulation of hypophosphorylated Rb. Finally, XCT790 reduces cell tumorigenicity in Nude mice. PMID:19546226

  13. Quality control of estrogen receptor assays.

    PubMed

    Godolphin, W; Jacobson, B

    1980-01-01

    Four types of material have been used for the quality control of routine assays of estrogen receptors in human breast tumors. Pieces of hormone-dependent Nb rat mammary tumors gave a precision about 40%. Rat uteri and rat tumors pulverized at liquid nitrogen temperature and stored as powder yielded precision about 30%. Powdered and lyophilised human tumors appear the best with precision as good as 17%.

  14. Breast Cancer Risk Factors Defined by Estrogen and Progesterone Receptor Status

    PubMed Central

    Monroe, Kristine R.; Wilkens, Lynne R.; Kolonel, Laurence N.; Pike, Malcolm C.; Henderson, Brian E.

    2009-01-01

    Prospective data on ethnic differences in hormone receptor-defined subtypes of breast cancer and their risk factor profiles are scarce. The authors examined the joint distributions of estrogen receptor (ER) and progesterone receptor (PR) status across 5 ethnic groups and the associations of established risk factors with ER/PR status in the Multiethnic Cohort Study (Hawaii and Los Angeles, California). During an average of 10.4 years of follow-up of 84,427 women between 1993–1996 and 2004/2005, 2,543 breast cancer cases with data on ER/PR status were identified: 1,672 estrogen receptor-positive (ER+)/progesterone receptor-positive (PR+); 303 ER+/progesterone receptor-negative (PR−); 77 estrogen receptor-negative (ER−)/PR+; and 491 ER−/PR−. ER/PR status varied significantly across racial/ethnic groups even within the same tumor stage (for localized tumors, P < 0.0001; for advanced tumors, P = 0.01). The highest fraction of ER−/PR− tumors was observed in African Americans (31%), followed by Latinas (25%), Whites (18%), Japanese (14%), and Native Hawaiians (14%). Associations differed between ER+/PR+ and ER−/PR− cases for postmenopausal obesity (P = 0.02), age at menarche (P = 0.05), age at first birth (P = 0.04), and postmenopausal hormone use (P < 0.0001). African Americans are more likely to be diagnosed with ER−/PR− tumors independently of stage at diagnosis, and there are disparate risk factor profiles across the ER/PR subtypes of breast cancer. PMID:19318616

  15. G protein-coupled estrogen receptor regulates embryonic heart rate in zebrafish

    PubMed Central

    Romano, Shannon N.; Edwards, Hailey E.; Ryan, Kevin J.

    2017-01-01

    Estrogens act by binding to estrogen receptors alpha and beta (ERα, ERβ), ligand-dependent transcription factors that play crucial roles in sex differentiation, tumor growth and cardiovascular physiology. Estrogens also activate the G protein-coupled estrogen receptor (GPER), however the function of GPER in vivo is less well understood. Here we find that GPER is required for normal heart rate in zebrafish embryos. Acute exposure to estrogens increased heart rate in wildtype and in ERα and ERβ mutant embryos but not in GPER mutants. GPER mutant embryos exhibited reduced basal heart rate, while heart rate was normal in ERα and ERβ mutants. We detected gper transcript in discrete regions of the brain and pituitary but not in the heart, suggesting that GPER acts centrally to regulate heart rate. In the pituitary, we observed gper expression in cells that regulate levels of thyroid hormone triiodothyronine (T3), a hormone known to increase heart rate. Compared to wild type, GPER mutants had reduced levels of T3 and estrogens, suggesting pituitary abnormalities. Exposure to exogenous T3, but not estradiol, rescued the reduced heart rate phenotype in gper mutant embryos, demonstrating that T3 acts downstream of GPER to regulate heart rate. Using genetic and mass spectrometry approaches, we find that GPER regulates maternal estrogen levels, which are required for normal embryonic heart rate. Our results demonstrate that estradiol plays a previously unappreciated role in the acute modulation of heart rate during zebrafish embryonic development and suggest that GPER regulates embryonic heart rate by altering maternal estrogen levels and embryonic T3 levels. PMID:29065151

  16. G protein-coupled estrogen receptor regulates embryonic heart rate in zebrafish.

    PubMed

    Romano, Shannon N; Edwards, Hailey E; Souder, Jaclyn Paige; Ryan, Kevin J; Cui, Xiangqin; Gorelick, Daniel A

    2017-10-01

    Estrogens act by binding to estrogen receptors alpha and beta (ERα, ERβ), ligand-dependent transcription factors that play crucial roles in sex differentiation, tumor growth and cardiovascular physiology. Estrogens also activate the G protein-coupled estrogen receptor (GPER), however the function of GPER in vivo is less well understood. Here we find that GPER is required for normal heart rate in zebrafish embryos. Acute exposure to estrogens increased heart rate in wildtype and in ERα and ERβ mutant embryos but not in GPER mutants. GPER mutant embryos exhibited reduced basal heart rate, while heart rate was normal in ERα and ERβ mutants. We detected gper transcript in discrete regions of the brain and pituitary but not in the heart, suggesting that GPER acts centrally to regulate heart rate. In the pituitary, we observed gper expression in cells that regulate levels of thyroid hormone triiodothyronine (T3), a hormone known to increase heart rate. Compared to wild type, GPER mutants had reduced levels of T3 and estrogens, suggesting pituitary abnormalities. Exposure to exogenous T3, but not estradiol, rescued the reduced heart rate phenotype in gper mutant embryos, demonstrating that T3 acts downstream of GPER to regulate heart rate. Using genetic and mass spectrometry approaches, we find that GPER regulates maternal estrogen levels, which are required for normal embryonic heart rate. Our results demonstrate that estradiol plays a previously unappreciated role in the acute modulation of heart rate during zebrafish embryonic development and suggest that GPER regulates embryonic heart rate by altering maternal estrogen levels and embryonic T3 levels.

  17. Estrogen Receptor-Related Receptor α Mediates Up-Regulation of Aromatase Expression by Prostaglandin E2 in Prostate Stromal Cells

    PubMed Central

    Miao, Lin; Shi, Jiandang; Wang, Chun-Yu; Zhu, Yan; Du, Xiaoling; Jiao, Hongli; Mo, Zengnan; Klocker, Helmut; Lee, Chung; Zhang, Ju

    2010-01-01

    Estrogen receptor-related receptor α (ERRα) is an orphan member of the nuclear receptor superfamily of transcription factors. ERRα is highly expressed in the prostate, especially in prostate stromal cells. However, little is known about the regulation and function of ERRα, which may contribute to the progression of prostatic diseases. We previously found that prostaglandin E2 (PGE2) up-regulated the expression of aromatase in prostate stromal cells. Here we show that PGE2 also up-regulates the expression of ERRα, which, as a transcription factor, further mediates the regulatory effects of PGE2 on the expression of aromatase. ERRα expression was up-regulated by PGE2 in prostate stromal cell line WPMY-1, which was mediated mainly through the protein kinase A signaling pathway by PGE2 receptor EP2. Suppression of ERRα activity by chlordane (an antagonist of ERRα) or small interfering RNA knockdown of ERRα blocked the increase of expression and promoter activity of aromatase induced by PGE2. Overexpression of ERRα significantly increased aromatase expression and promoter activity, which were further augmented by PGE2. Chromatin immunoprecipitation assay demonstrated that ERRα directly bound to the aromatase promoter in vivo, and PGE2 enhanced the recruitment of ERRα and promoted transcriptional regulatory effects on aromatase expression in WPMY-1. 17β-Estradiol concentration in WPMY-1 medium was up-regulated by ERRα expression, and that was further increased by PGE2. Our results provided evidence that ERRα contributed to local estrogen production by up-regulating aromatase expression in response to PGE2 and provided further insights into the potential role of ERRα in estrogen-related prostatic diseases. PMID:20351196

  18. Involvement of estrogen receptor variant ER-alpha36, not GPR30, in nongenomic estrogen signaling.

    PubMed

    Kang, Lianguo; Zhang, Xintian; Xie, Yan; Tu, Yaping; Wang, Dong; Liu, Zhenming; Wang, Zhao-Yi

    2010-04-01

    Accumulating evidence suggested that an orphan G protein-coupled receptor (GPR)30, mediates nongenomic responses to estrogen. The present study was performed to investigate the molecular mechanisms underlying GPR30 function. We found that knockdown of GPR30 expression in breast cancer SK-BR-3 cells down-regulated the expression levels of estrogen receptor (ER)-alpha36, a variant of ER-alpha. Introduction of a GPR30 expression vector into GPR30 nonexpressing cells induced endogenous ER-alpha36 expression, and cotransfection assay demonstrated that GPR30 activated the promoter activity of ER-alpha36 via an activator protein 1 binding site. Both 17beta-estradiol (E2) and G1, a compound reported to be a selective GPR30 agonist, increased the phosphorylation levels of the MAPK/ERK1/2 in SK-BR-3 cells, which could be blocked by an anti-ER-alpha36-specific antibody against its ligand-binding domain. G1 induced activities mediated by ER-alpha36, such as transcription activation activity of a VP16-ER-alpha36 fusion protein and activation of the MAPK/ERK1/2 in ER-alpha36-expressing cells. ER-alpha36-expressing cells, but not the nonexpressing cells, displayed high-affinity, specific E2 and G1 binding, and E2- and G1-induced intracellular Ca(2+) mobilization only in ER-alpha36 expressing cells. Taken together, our results demonstrated that previously reported activities of GPR30 in response to estrogen were through its ability to induce ER-alpha36 expression. The selective G protein-coupled receptor (GPR)30 agonist G1 actually interacts with ER-alpha36. Thus, the ER-alpha variant ER-alpha36, not GPR30, is involved in nongenomic estrogen signaling.

  19. Melanocortin 4 receptor is not required for estrogenic regulations on energy homeostasis and reproduction

    USDA-ARS?s Scientific Manuscript database

    Brain estrogen receptor-a (ERa) is essential for estrogenic regulation of energy homeostasis and reproduction. We previously showed that ERa expressed by pro-opiomelanocortin (POMC) neurons mediates estrogen's effects on food intake, body weight, negative regulation of hypothalamic–pituitary–gonadal...

  20. Identifying a Mechanism for Crosstalk Between the Estrogen and Glucocorticoid Receptors | Center for Cancer Research

    Cancer.gov

    Estrogen has long been known to play important roles in the development and progression of breast cancer. Its receptor (ER), a member of the steroid receptor family, binds to estrogen response elements (EREs) in DNA and regulates gene transcription. More recently, another steroid receptor family member, the glucocorticoid receptor (GR), has been implicated in breast cancer progression, and ER/GR status is an important predictor of breast cancer outcome.

  1. Activation of G protein-coupled estrogen receptor 1 (GPER-1) decreases fluid intake in female rats

    PubMed Central

    Santollo, Jessica; Daniels, Derek

    2015-01-01

    Estradiol (E2) decreases fluid intake in the female rat and recent studies from our lab demonstrate that the effect is at least in part mediated by membrane-associated estrogen receptors. Because multiple estrogen receptor subtypes can localize to the cell membrane, it is unclear which receptor(s) is generating the anti-dipsogenic effect of E2. The G protein-coupled estrogen receptor 1 (GPER-1) is a particularly interesting possibility because it has been shown to regulate blood pressure; many drinking-regulatory systems play overlapping roles in the control of blood pressure. Accordingly, we tested the hypothesis that activation of GPER-1 is sufficient to decrease fluid intake in female rats. In support of this hypothesis we found that treatment with the selective GPER-1 agonist G1 reduced AngII-stimulated fluid intake in OVX rats. Given the close association between food and fluid intakes in rats, and previous reports suggesting GPER-1 plays a role in energy homeostasis, we tested the hypothesis that the effect of GPER-1 on fluid intake was caused by a more direct effect on food intake. We found, however, that G1-treatment did not influence short-term or overnight food intake in OVX rats. Together these results reveal a novel effect of GPER-1 in the control of drinking behavior and provide an example of the divergence in the controls of fluid and food intakes in female rats. PMID:26093261

  2. Activation of G protein-coupled estrogen receptor 1 (GPER-1) decreases fluid intake in female rats.

    PubMed

    Santollo, Jessica; Daniels, Derek

    2015-07-01

    Estradiol (E2) decreases fluid intake in the female rat and recent studies from our lab demonstrate that the effect is at least in part mediated by membrane-associated estrogen receptors. Because multiple estrogen receptor subtypes can localize to the cell membrane, it is unclear which receptor(s) is generating the anti-dipsogenic effect of E2. The G protein-coupled estrogen receptor 1 (GPER-1) is a particularly interesting possibility because it has been shown to regulate blood pressure; many drinking-regulatory systems play overlapping roles in the control of blood pressure. Accordingly, we tested the hypothesis that activation of GPER-1 is sufficient to decrease fluid intake in female rats. In support of this hypothesis we found that treatment with the selective GPER-1 agonist G1 reduced AngII-stimulated fluid intake in OVX rats. Given the close association between food and fluid intakes in rats, and previous reports suggesting GPER-1 plays a role in energy homeostasis, we tested the hypothesis that the effect of GPER-1 on fluid intake was caused by a more direct effect on food intake. We found, however, that G1-treatment did not influence short-term or overnight food intake in OVX rats. Together these results reveal a novel effect of GPER-1 in the control of drinking behavior and provide an example of the divergence in the controls of fluid and food intakes in female rats. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Estrogen receptor-alpha promotes alternative macrophage activation during cutaneous repair.

    PubMed

    Campbell, Laura; Emmerson, Elaine; Williams, Helen; Saville, Charis R; Krust, Andrée; Chambon, Pierre; Mace, Kimberly A; Hardman, Matthew J

    2014-09-01

    Efficient local monocyte/macrophage recruitment is critical for tissue repair. Recruited macrophages are polarized toward classical (proinflammatory) or alternative (prohealing) activation in response to cytokines, with tight temporal regulation crucial for efficient wound repair. Estrogen acts as a potent anti-inflammatory regulator of cutaneous healing. However, an understanding of estrogen/estrogen receptor (ER) contribution to macrophage polarization and subsequent local effects on wound healing is lacking. Here we identify, to our knowledge previously unreported, a role whereby estrogen receptor α (ERα) signaling preferentially polarizes macrophages from a range of sources to an alternative phenotype. Cell-specific ER ablation studies confirm an in vivo role for inflammatory cell ERα, but not ERβ, in poor healing associated with an altered cytokine profile and fewer alternatively activated macrophages. Furthermore, we reveal intrinsic changes in ERα-deficient macrophages, which are unable to respond to alternative activation signals in vitro. Collectively, our data reveal that inflammatory cell-expressed ERα promotes alternative macrophage polarization, which is beneficial for timely healing. Given the diverse physiological roles of ERs, these findings will likely be of relevance to many pathologies involving excessive inflammation.

  4. Estrogen promotes cutaneous wound healing via estrogen receptor β independent of its antiinflammatory activities

    PubMed Central

    Campbell, Laura; Emmerson, Elaine; Davies, Faith; Gilliver, Stephen C.; Krust, Andre; Chambon, Pierre; Ashcroft, Gillian S.

    2010-01-01

    Post-menopausal women have an increased risk of developing a number of degenerative pathological conditions, linked by the common theme of excessive inflammation. Systemic estrogen replacement (in the form of hormone replacement therapy) is able to accelerate healing of acute cutaneous wounds in elderly females, linked to its potent antiinflammatory activity. However, in contrast to many other age-associated pathologies, the detailed mechanisms through which estrogen modulates skin repair, particularly the cell type–specific role of the two estrogen receptors, ERα and ERβ, has yet to be determined. Here, we use pharmacological activation and genetic deletion to investigate the role of both ERα and ERβ in cutaneous tissue repair. Unexpectedly, we report that exogenous estrogen replacement to ovariectomised mice in the absence of ERβ actually delayed wound healing. Moreover, healing in epidermal-specific ERβ null mice (K14-cre/ERβL2/L2) largely resembled that in global ERβ null mice. Thus, the beneficial effects of estrogen on skin wound healing are mediated by epidermal ERβ, in marked contrast to most other tissues in the body where ERα is predominant. Surprisingly, agonists to both ERα and ERβ are potently antiinflammatory during skin repair, indicating clear uncoupling of inflammation and overall efficiency of repair. Thus, estrogen-mediated antiinflammatory activity is not the principal factor in accelerated wound healing. PMID:20733032

  5. Estrogen receptor, progesterone receptor and CD8+ expression in endometrium of women of unexplained infertility.

    PubMed

    Dixit, Shilpi Gupta; Ghatak, Surajit; Singh, Pratibha; Bhattacharya, Shilajit

    2018-05-18

    The present study aimed to investigate the changes of endometrial progesterone and estrogen receptors in luteal phase biopsy specimens of infertile women and find a correlation, if any, between these and CD8+ receptors in the same. The study was conducted on luteal phase endometrial biopsy specimens of 30 women of unexplained infertility and 15 age matched controls. Paraffin sections were first H & E stained. A standardized immunohistochemical protocol was then used to localize the estrogen, progesterone and CD8+ receptors in these samples that were expressed as percentage positivity. Unpaired T test was applied between the controls and cases both for epithelial and stromal cells. The data was also analyzed for correlation in cases for the positivity of CD8+ Cells with that of ER and PR. The positivity of estrogen receptors (ER) in stromal cells was significantly lower (p<0.001) in the infertile women when compared to controls and in both the epithelial and stromal cells for progesterone receptors (p<0.001). The results were non significant for CD8+ cells (p=0.19) and also showed no significant correlation in the positivity of CD8+ cells with that of ER and PR. The development of molecular probe like ER and PR positivity in endometrial epithelial and stromal cells allows a new approach to be made to the characterization of normal and defective endometrial function. Copyright © 2018. Published by Elsevier Masson SAS.

  6. Genomic agonism and phenotypic antagonism between estrogen and progesterone receptors in breast cancer

    PubMed Central

    Singhal, Hari; Greene, Marianne E.; Tarulli, Gerard; Zarnke, Allison L.; Bourgo, Ryan J.; Laine, Muriel; Chang, Ya-Fang; Ma, Shihong; Dembo, Anna G.; Raj, Ganesh V.; Hickey, Theresa E.; Tilley, Wayne D.; Greene, Geoffrey L.

    2016-01-01

    The functional role of progesterone receptor (PR) and its impact on estrogen signaling in breast cancer remain controversial. In primary ER+ (estrogen receptor–positive)/PR+ human tumors, we report that PR reprograms estrogen signaling as a genomic agonist and a phenotypic antagonist. In isolation, estrogen and progestin act as genomic agonists by regulating the expression of common target genes in similar directions, but at different levels. Similarly, in isolation, progestin is also a weak phenotypic agonist of estrogen action. However, in the presence of both hormones, progestin behaves as a phenotypic estrogen antagonist. PR remodels nucleosomes to noncompetitively redirect ER genomic binding to distal enhancers enriched for BRCA1 binding motifs and sites that link PR and ER/PR complexes. When both hormones are present, progestin modulates estrogen action, such that responsive transcriptomes, cellular processes, and ER/PR recruitment to genomic sites correlate with those observed with PR alone, but not ER alone. Despite this overall correlation, the transcriptome patterns modulated by dual treatment are sufficiently different from individual treatments, such that antagonism of oncogenic processes is both predicted and observed. Combination therapies using the selective PR modulator/antagonist (SPRM) CDB4124 in combination with tamoxifen elicited 70% cytotoxic tumor regression of T47D tumor xenografts, whereas individual therapies inhibited tumor growth without net regression. Our findings demonstrate that PR redirects ER chromatin binding to antagonize estrogen signaling and that SPRMs can potentiate responses to antiestrogens, suggesting that cotargeting of ER and PR in ER+/PR+ breast cancers should be explored. PMID:27386569

  7. Differential neonatal imprinting and regulation by estrogen of estrogen receptor subtypes alpha and beta and of the truncated estrogen receptor product (TERP-1) mRNA expression in the male rat pituitary.

    PubMed

    Tena-Sempere, M; Barreiro, M L; González, L C; Pinilla, L; Aguilar, E

    2001-11-01

    Two distinct nuclear estrogen receptors (ERs) have been identified, the classical one, renamed ERalpha, and the more recently cloned ERbeta. In a variety of tissues, gene expression of both receptor subtypes results in the generation of multiple transcripts encoding the full-length as well as several alternately spliced isoforms. In the rat pituitary, a truncated, tissue-specific variant of ERalpha, called TERP-1, has been identified and found able to modulate ERalpha and ERbeta activity. So far, its pattern of expression and hormonal regulation have been mostly studied in females. The present study was designed to analyze the pattern of expression of TERP-1 mRNA in the male rat pituitary at different stages of postnatal development, and to evaluate the impact of neonatal imprinting and estrogen treatment upon TERP-1 expression in the male pituitary. Assessment of TERP-1 mRNA levels by semi-quantitative RT-PCR, using a variant-specific primer pair, revealed that TERP-1 is also expressed in the male rat pituitary. Relative mRNA expression levels changed markedly during postnatal development, with moderate expression of the TERP-1 transcript at birth, barely detectable levels during the infantile-prepubertal period, and maximal values in adulthood. Expression of TERP-1 was sensitive to neonatal estrogen exposure, which resulted in a significant, persistent increase in mRNA levels from the infantile period until puberty. This phenomenon was not mimicked by neonatal blockade of endogenous GnRH. In addition, estrogen was able to acutely up-regulate pituitary TERP-1 mRNA expression levels in prepubertal (30-day-old) and adult (75-day-old) males. Interestingly, neonatal imprinting as well as acute estrogen treatment resulted in opposite effects on TERP-1 and full-length ERalpha and ERbeta transcripts, the latter being decreased under both conditions. In conclusion, our data indicate that TERP-1 mRNA is expressed in a developmentally regulated manner in the male rat

  8. Targeting estrogen/estrogen receptor alpha enhances Bacillus Calmette-Guérin efficacy in bladder cancer

    PubMed Central

    Shang, Zhiqun; Li, Yanjun; Hsu, Iawen; Zhang, Minghao; Tian, Jing; Wen, Simeng; Han, Ruifa; Messing, Edward M.; Chang, Chawnshang; Niu, Yuanjie; Yeh, Shuyuan

    2016-01-01

    Recent studies showed the potential linkage of estrogen/estrogen receptor signaling with bladder tumorigenesis, yet detailed mechanisms remain elusive. Here we found a new potential therapy with the combination of Bacillus Calmette Guerin (BCG) and the anti-estrogen ICI 182,780 led to better suppression of bladder cancer (BCa) than BCG alone. Mechanism dissection found ICI 182,780 could promote BCG attachment/internalization to the BCa cells through increased integrin-α5β1 expression and IL-6 release, which may enhance BCG-induced suppression of BCa cell growth via recruiting more monocytes/macrophages to BCa cells and increased TNF-α release. Consistently, in vivo studies found ICI 182,780 could potentiate the anti-BCa effects of BCG in the carcinogen-induced mouse BCa models. Together, these in vitro and in vivo results suggest that combining BCG with anti-estrogen may become a new therapeutic approach with better efficacy to suppress BCa progression and recurrence. PMID:27092883

  9. Targeting estrogen/estrogen receptor alpha enhances Bacillus Calmette-Guérin efficacy in bladder cancer.

    PubMed

    Shang, Zhiqun; Li, Yanjun; Hsu, Iawen; Zhang, Minghao; Tian, Jing; Wen, Simeng; Han, Ruifa; Messing, Edward M; Chang, Chawnshang; Niu, Yuanjie; Yeh, Shuyuan

    2016-05-10

    Recent studies showed the potential linkage of estrogen/estrogen receptor signaling with bladder tumorigenesis, yet detailed mechanisms remain elusive. Here we found a new potential therapy with the combination of Bacillus Calmette-Guerin (BCG) and the anti-estrogen ICI 182,780 led to better suppression of bladder cancer (BCa) than BCG alone. Mechanism dissection found ICI 182,780 could promote BCG attachment/internalization to the BCa cells through increased integrin-α5β1 expression and IL-6 release, which may enhance BCG-induced suppression of BCa cell growth via recruiting more monocytes/macrophages to BCa cells and increased TNF-α release. Consistently, in vivo studies found ICI 182,780 could potentiate the anti-BCa effects of BCG in the carcinogen-induced mouse BCa models. Together, these in vitro and in vivo results suggest that combining BCG with anti-estrogen may become a new therapeutic approach with better efficacy to suppress BCa progression and recurrence.

  10. Identification of estrogenic and antiestrogenic activities of respirable diesel exhaust particles by bioassay-directed fractionation.

    PubMed

    Oh, Seung Min; Ryu, Byung Taek; Chung, Kyu Hyuck

    2008-01-01

    Bioassay-directed fractionation was performed to identify causative chemical groups of DEPs with estrogenic and antiestrogenic activities. Bioassay-directed fractionation consists of a cell bioassay (E-SCREEN) in conjunction with acid-base partitioning (F1 and F2) and silica gel column fractionation of neutral fractions (F3-F7). Crude extract (CE) of DEPs in dichloromethane (DCM) exhibited both estrogenic and antiestrogenic activity. Estrogenic activity of CE and some fractions (F1, F2, F3, F5 and F6) was induced through estrogen receptor (ER)-mediated pathways. In particular, the acid polar fraction (F2) of DEPs, which contains phenols, induced high levels of estrogenic activity compared to other fractions. The estrogenic activity of F2 (610.80 pg-bio-EEQ/g-DEPs) was higher than that of the total estrogenic activity of CE (222.22 pg-bio-EEQ/g-DEPs). This result indicates that the estrogenic activity induced by causative estrogenic fraction (F2) may be antagonized by unidentified chemicals in DEPs. On the other hand, non-polar fractions (F3 and F4) of DEPs include aliphatic and chlorinated hydrocarbon, polyaromatic hydrocarbons, and their alkyl derivatives, which play an important role in the antiestrogenic activity of DEPs. In particular, F4, which contains PAH and its derivatives, showed the highest antiestrogenic activity. Since in our previous study, dibenzo(a, h)anthracene and chrysene were identified in F4, and these chemicals have antiestrogenic activity, we assume that these chemicals are the major causative chemicals with antiestrogenic activity in DEPs. In contrast to the estrogenic activity of DEPs, antiestrogenic activity of CE was stronger than that of antiestrogenic fractions (F3 and F4) at non-cytotoxic concentrations, indicating that additive or synergistic effects by unidentified chemicals contained in DEPs occurred.

  11. Cardioprotective role of G-Protein Coupled Estrogen Receptor 1 (GPER1).

    PubMed

    Koganti, Sivaramakrishna

    2015-01-01

    G-Protein Coupled Estrogen Receptor 1 (GPER1), also known as G-Protein Coupled Receptor 30 (GPR30) and initially considered an orphan receptor, has become one of the most important pharmacological targets in cardiovascular research. Since the gene encoding this putative receptor was cloned nearly 20 years ago, researchers have addressed its role in various aspects of physiology, including cardioprotection. Although extensive research has been carried out to understand the role of GPER1 as a pharmacological target to treat cardiovascular diseases, there are few current reviews addressing the overall cardioprotective benefits of this receptor and the signaling intermediates involved. This review considers the origins of GPER1, its cell biology, its physiological and pharmacological roles as a therapeutic target in cardiovascular disease, and what future research on GPER1 might entail. More specifically, the review focuses on GPER1 regulation of Angiotensin Type I Receptor (AT1R) and the role of estrogen receptors, epidermal growth factor receptor (EGFR) and matrix metalloproteinases (MMPs) in bringing about the cardioprotective effects of GPER1. Areas where improved knowledge of GPER1 biology is still needed to better understand the receptor's cardioprotective effects are also discussed.

  12. Estrogen Receptors in Breast and Bone: from Virtue of Remodeling to Vileness of Metastasis

    PubMed Central

    Bado, Igor; Gugala, Zbigniew; Fuqua, Suzanne A. W.; Zhang, Xiang H.-F.

    2017-01-01

    Bone metastasis is a prominent cause of morbidity and mortality in cancer. High rates of bone colonization in breast cancer, especially in the subtype expressing estrogen receptors (ERs), suggests tissue-specific proclivities for metastatic tumor formation. The mechanisms behind this subtype-specific organ-tropism remains largely elusive. Interestingly, as the major driver of ER+ breast cancer, ERs also play important roles in bone development and homeostasis. Thus, any agents targeting ER will also inevitably affect the microenvironment, i.e., the osteoblasts and osteoclasts. Yet, how such microenvironmental effects are integrated with direct therapeutic responses of cancer cells remain poorly understood. Recent findings on ER mutations, especially their enrichment in bone metastasis, raised even more provocative questions on the role of ER in cancer-bone interaction. In this review, we evaluate the importance of estrogen receptors (ERs) in bone metastasis and discuss new avenues of investigation for bone metastasis treatment based on current knowledge. PMID:28368409

  13. Hispolon inhibits the growth of estrogen receptor positive human breast cancer cells through modulation of estrogen receptor alpha

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jang, Eun Hyang; Jang, Soon Young; Cho, In-Hye

    Human estrogen receptor α (ERα) is a nuclear transcription factor that is a major therapeutic target in breast cancer. The transcriptional activity of ERα is regulated by certain estrogen-receptor modulators. Hispolon, isolated from Phellinus linteus, a traditional medicinal mushroom called Sanghwang in Korea, has been used to treat various pathologies, such as inflammation, gastroenteric disorders, lymphatic diseases, and cancers. In this latter context, Hispolon has been reported to exhibit therapeutic efficacy against various cancer cells, including melanoma, leukemia, hepatocarcinoma, bladder cancer, and gastric cancer cells. However, ERα regulation by Hispolon has not been reported. In this study, we investigated themore » effects of Hispolon on the growth of breast cancer cells. We found that Hispolon decreased expression of ERα at both mRNA and the protein levels in MCF7 and T47D human breast cancer cells. Luciferase reporter assays showed that Hispolon decreased the transcriptional activity of ERα. Hispolon treatment also inhibited expression of the ERα target gene pS2. We propose that Hispolon, an anticancer drug extracted from natural sources, inhibits cell growth through modulation of ERα in estrogen-positive breast cancer cells and is a candidate for use in human breast cancer chemotherapy. - Highlights: • Hispolon decreased ERα expression at both mRNA and protein levels. • Hispolon decreased ERα transcriptional activity. • Hispolon treatment inhibited expression of ERα target gene pS2. • Shikonin is a candidate chemotherapeutic target in the treatment of human breast cancer.« less

  14. Epidermal growth factor receptor (EGFR) transactivation by estrogen via the G-protein-coupled receptor, GPR30: a novel signaling pathway with potential significance for breast cancer.

    PubMed

    Filardo, Edward J

    2002-02-01

    The biological and biochemical effects of estrogen have been ascribed to its known receptors, which function as ligand-inducible transcription factors. However, estrogen also triggers rapid activation of classical second messengers (cAMP, calcium, and inositol triphosphate) and stimulation of intracellular signaling cascades mitogen-activated protein kinase (MAP K), PI3K and eNOS. These latter events are commonly activated by membrane receptors that either possess intrinsic tyrosine kinase activity or couple to heterotrimeric G-proteins. We have shown that estrogen transactivates the epidermal growth factor receptor (EGFR) to MAP K signaling axis via the G-protein-coupled receptor (GPCR), GPR30, through the release of surface-bound proHB-EGF from estrogen receptor (ER)-negative human breast cancer cells [Molecular Endocrinology 14 (2000) 1649]. This finding is consistent with a growing body of evidence suggesting that transactivation of EGFRs by GPCRs is a recurrent theme in cell signaling. GPCR-mediated transactivation of EGFRs by estrogen provides a previously unappreciated mechanism of cross-talk between estrogen and serum growth factors, and explains prior data reporting the EGF-like effects of estrogen. This novel mechanism by which estrogen activates growth factor-dependent signaling and its implications for breast cancer biology are discussed further in this review.

  15. Involvement of epidermal growth factor receptor signaling in estrogen inhibition of oocyte maturation mediated through the G protein-coupled estrogen receptor (Gper) in zebrafish (Danio rerio).

    PubMed

    Peyton, Candace; Thomas, Peter

    2011-07-01

    Oocyte maturation (OM) in teleosts is under precise hormonal control by progestins and estrogens. We show here that estrogens activate an epidermal growth factor receptor (Egfr) signaling pathway in fully grown, denuded zebrafish (Danio rerio) oocytes through the G protein-coupled estrogen receptor (Gper; also known as GPR30) to maintain oocyte meiotic arrest in a germinal vesicle breakdown (GVBD) bioassay. A GPER-specific antagonist, G-15, increased spontaneous OM, indicating that the inhibitory estrogen actions on OM are mediated through Gper. Estradiol-17beta-bovine serum albumin, which cannot enter oocytes, decreased GVBD, whereas treatment with actinomycin D did not block estrogen's inhibitory effects, suggesting that estrogens act at the cell surface via a nongenomic mechanism to prevent OM. The intracellular tyrosine kinase (Src) inhibitor, PP2, blocked estrogen inhibition of OM. Expression of egfr mRNA and Egfr protein were detected in denuded zebrafish oocytes. The matrix metalloproteinase (MMP) inhibitor, ilomastat, which prevents the release of heparin-bound epidermal growth factor, increased spontaneous OM, whereas the MMP activator, interleukin-1alpha, decreased spontaneous OM. Moreover, inhibitors of EGFR (ErbB1) and extracellular-related kinase 1 and 2 (Erk1/2; official symbol Mapk3/1) increased spontaneous OM. In addition, estradiol-17beta and the GPER agonist, G-1, increased phosphorylation of Erk, and this was abrogated by simultaneous treatment with the EGFR inhibitor. Taken together, these results suggest that estrogens act through Gper to maintain meiotic arrest via an Src kinase-dependent G-protein betagamma subunit signaling pathway involving transactivation of egfr and phosphorylation of Mapk3/1. To our knowledge, this is the first evidence that EGFR signaling in vertebrate oocytes can prevent meiotic progression.

  16. Formononetin upregulates nitric oxide synthase in arterial endothelium through estrogen receptors and MAPK pathways.

    PubMed

    Sun, Tao; Cao, Lei; Ping, Na-Na; Wu, Yue; Liu, Dong-Zheng; Cao, Yong-Xiao

    2016-03-01

    Formononetin, a phytoestrogen, can improve arterial endothelial cell function by upregulating endothelial nitric oxide synthase (eNOS). The estrogen receptor plays an important role in the regulation of eNOS. This study investigated the hypothesis that formononetin upregulates eNOS through estrogen receptors and MAPK pathways. The rat superior mesenteric arteries were cultured with formononetin or formononetin plus inhibitors for 24 h. The isometric tension of the arteries was measured using a myograph system. The mRNA and protein expression levels of eNOS were determined by real-time PCR and immunohistochemistry, respectively. Acetylcholine (ACh) relaxed the mesenteric arteries precontracted with 5-hydroxytryptamine. This relaxation could be enhanced by formononetin. The removal of endothelium or incubation with l-NAME (a NOS inhibitor) completely abolished the formononetin-enhanced relaxation induced by ACh, suggesting that the formononetin-enhanced vasodilatation is dependent on endothelium and NO pathway. The estrogen receptor inhibitor ICI 182780 attenuated the formononetin-enhanced vasodilatation induced by ACh, suggesting that the formononetin-enhanced arterial relaxation is mediated by the estrogen receptor. Formononetin increased the mRNA and protein expression levels of eNOS. ICI 182780, U0126 (an ERK1/2 inhibitor) and SP600125 (a JNK inhibitor) prevented the increases in arterial relaxation and eNOS levels. Formononetin upregulates eNOS expression in mesenteric arteries via estrogen receptors, ERK1/2 and JNK pathways. © 2016 Royal Pharmaceutical Society, Journal of Pharmacy and Pharmacology.

  17. [Estrogen receptor alpha in obesity and diabetes].

    PubMed

    Cahua-Pablo, José Ángel; Flores-Alfaro, Eugenia; Cruz, Miguel

    2016-01-01

    Estradiol (E2) is an important hormone in reproductive physiology, cardiovascular, skeletal and in the central nervous system (CNS). In human and rodents, E2 and its receptors are involved in the control of energy and glucose metabolism in health and metabolic diseases. The estrogen receptor (ER) belongs to the superfamily of nuclear receptors (NR), which are transcription factors that regulate gene expression. Three ER, ER-alpha, ER-beta and the G protein-coupled ER (GPER; also called GPR30) in tissues are involved in glucose and lipid homeostasis. Also, it may have important implications for risk factors associated with metabolic syndrome (MS), insulin resistance (IR), obesity and type 2 diabetes (T2D).

  18. The high mobility group protein 1 enhances binding of the estrogen receptor DNA binding domain to the estrogen response element.

    PubMed

    Romine, L E; Wood, J R; Lamia, L A; Prendergast, P; Edwards, D P; Nardulli, A M

    1998-05-01

    We have examined the ability of the high-mobility group protein 1 (HMG1) to alter binding of the estrogen receptor DNA-binding domain (DBD) to the estrogen response element (ERE). HMG1 dramatically enhanced binding of purified, bacterially expressed DBD to the consensus vitellogenin A2 ERE in a dose-dependent manner. The ability of HMG1 to stabilize the DBD-ERE complex resulted in part from a decrease in the dissociation rate of the DBD from the ERE. Antibody supershift experiments demonstrated that HMG1 was also capable of forming a ternary complex with the ERE-bound DBD in the presence of HMG1-specific antibody. HMG1 did not substantially affect DBD-ERE contacts as assessed by methylation interference assays, nor did it alter the ability of the DBD to induce distortion in ERE-containing DNA fragments. Because HMG1 dramatically enhanced estrogen receptor DBD binding to the ERE, and the DBD is the most highly conserved region among the nuclear receptor superfamily members, HMG1 may function to enhance binding of other nuclear receptors to their respective response elements and act in concert with coactivator proteins to regulate expression of hormone-responsive genes.

  19. Src-JNK Potentiation of Estrogen Receptor AF-1; Mechanism, and Role in Estrogen Action in Breast Cancer

    DTIC Science & Technology

    2002-08-01

    an increase in estrogen receptor activity. A second objective is to understand the potential role of Src in estrogen induced mammary ductal development ...bPcis i on to The Ser-ilS-dependent link wt GR- t KaroBio AB, a Swedish pharmaceutical development company with CBP is in addition to the Ser-1l8...the ECL detection kit (Amersham Pharmacia Biotech ). phoresis, stained with Coomassic Blue to monitor expression, and sub- Fluorescence Microscopy

  20. A novel estrogen receptor GPER mediates proliferation induced by 17β-estradiol and selective GPER agonist G-1 in estrogen receptor α (ERα)-negative ovarian cancer cells.

    PubMed

    Liu, Huidi; Yan, Yan; Wen, Haixia; Jiang, Xueli; Cao, Xuefeng; Zhang, Guangmei; Liu, Guoyi

    2014-05-01

    G protein-coupled estrogen receptor (GPER) is recently identified as a membrane-associated estrogen receptor that mediates non-genomic effects of estrogen. Our previous immunohistochemistry study found an association between GPER and the proliferation of epithelial ovarian cancer. However, the contributions and mechanisms of GPER in the proliferation of ovarian cancers are not clear. We have examined the role of GPER in estrogen receptor α (ERα)-negative/GPER positive OVCAR5 ovarian cancer cell line. MTT assay was used to detect cell proliferation. BrdU incorporation assay was used to measure the cells in S-phase. Protein expression of marker genes of proliferation, cell cycle and apoptosis were examined by Western blot. The results showed that 17β-estradiol and selective GPER agonist G-1 stimulated the proliferation of OVCAR5 cells and increased the cells in S-phase. Both ligands upregulated the protein levels of c-fos and cyclin D1. Small interfering RNA targeting GPER or G protein inhibitor pertussin toxin (PTX) inhibited basal cell proliferation and attenuated 17β-estradiol- or G-1-induced cell proliferation. GPER mediated cell growth was also associated with the apoptosis of OVCAR5 cells. These findings suggest that GPER has an important function in the proliferation of ovarian cancer cells lacking ERα. GPER might be a promising therapeutic target in ovarian cancer. © 2014 International Federation for Cell Biology.

  1. Integrated Summary Report: Validation of Two Binding Assays Using Human Recombinant Estrogen Receptor Alpha (hrERa)

    EPA Science Inventory

    This Integrated Summary Report (ISR) summarizes, in a single document, the results from an international multi-laboratory validation study conducted for two in vitro estrogen receptor (ER) binding assays. These assays both use human recombinant estrogen receptor, alpha subtype (h...

  2. Homology Modeling, Validation and Dynamics of the G Protein-coupled Estrogen Receptor 1 (GPER-1).

    PubMed

    Bruno, Agostino; Aiello, Francesca; Costantino, Gabriele; Radi, Marco

    2016-09-01

    Estrogens exert their action mainly by binding three receptors, namely estrogen receptors α and β (ERα and ERβ) and GPER-1 (G-protein coupled estrogen receptor 1). While the patho-physiological role of both ERα and ERβ has been deeply investigated, the role of GPER-1 in estrogens' signaling has not been clearly defined yet. Unfortunately, only few GPER-1 selective ligands were discovered so far, and the real efficiency of such compounds is still matter of debate. To better understand the physiological relevance of GPER-1, new selective chemical probes are higly needed. In this scenario, we report herein the generation and validation of a three-dimensional (3-D) GPER-1 homology model by means of docking studies and molecular dynamics simulations. The model thus generated was employed to (i) decipher the structural basis underlying the ability of estrogens and some Selective Estrogen Receptor Modulators (SERMs) to bind GPER-1 and classical ERα and ERβ, and (ii) generate a reliable G1/GPER-1 complex useful in rationalizing the pharmacological profile of G1 reported in the literature. The G1/GPER-1 complex herein reported could be further exploited in drug design approaches aimed at improving the pharmacological profile of G1 or at identifying new chemical entities (NCEs) as potential modulators of GPER-1. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. The novel estrogen receptor G-protein-coupled receptor 30 is expressed in human bone.

    PubMed

    Heino, Terhi J; Chagin, Andrei S; Sävendahl, Lars

    2008-05-01

    Estrogens have significant impact on bone mineral metabolism. Besides the classical estrogen receptors (ERalpha and ERbeta), a trans-membrane G-protein-coupled receptor (GPR30) has been demonstrated to mediate estrogenic effects. We aimed to study whether GPR30 is expressed in bone cells and if so, whether the level of expression is developmentally regulated. Metaphyseal bone biopsies were collected from the tibia in 14 boys and 6 girls, all at different stages of puberty. GPR30 protein expression was studied by immunohistochemistry in paraffin-embedded sections. GPR30-positive osteocytes and osteoblasts were quantified and linear regression analysis was applied. Cytoplasmic GPR30 expression was detected in osteoblasts, osteocytes, and osteoclasts. Osteocytes were more frequently positive for GPR30 than osteoblasts (58+/-4% vs 46+/-3% positive cells respectively, P<0.05). Detailed analysis demonstrated that GPR30 positivity declined during pubertal development in osteocytes (R=-0.56, P<0.01) but not in osteoblasts (R=-0.31, P>0.05). No sex difference was observed in the numbers of GPR30-positive osteoblasts or osteocytes. Furthermore, GPR30 expression did not correlate with chronological or bone age. In conclusion, the novel ER GPR30 is expressed in osteoblasts, osteocytes, and osteoclasts suggesting that non-genomic estrogen signaling via GPR30 may exist in bone. However, the functional role of GPR30 in bone tissue remains to be elucidated.

  4. Facile screening of potential xenoestrogens by an estrogen receptor-based reusable optical biosensor.

    PubMed

    Liu, Lanhua; Zhou, Xiaohong; Lu, Yun; Shan, Didi; Xu, Bi; He, Miao; Shi, Hanchang; Qian, Yi

    2017-11-15

    The apparent increase in hormone-induced cancers and disorders of the reproductive tract has led to a growing demand for new technologies capable of screening xenoestrogens. We reported an estrogen receptor (ER)-based reusable fiber biosensor for facile screening estrogenic compounds in environment. The bioassay is based on the competition of xenoestrogens with 17β-estradiol (E 2 ) for binding to the recombinant receptor of human estrogen receptor α (hERα) protein, leaving E 2 free to bind to fluorophore-labeled anti-E 2 monoclonal antibody. Unbound anti-E 2 antibody then binds to the immobilized E 2 -protein conjugate on the fiber surface, and is detected by fluorescence emission induced by evanescent field. As expected, the stronger estrogenic activity of xenoestrogen would result in the weaker fluorescent signal. Three estrogen-agonist compounds, diethylstilbestrol (DES), 4-n-nonylphenol (NP) and 4-n-octylphenol (OP), were chosen as a paradigm for validation of this assay. The rank order of estrogenic potency determined by this biosensor was DES>OP>NP, which were consistent with the published results in numerous studies. Moreover, the E 2 -protein conjugate modified optical fiber was robust enough for over 300 sensing cycles with the signal recoveries ranging from 90% to 100%. In conclusion, the biosensor is reusable, reliable, portable and amenable to on-line operation, providing a facile, efficient and economical alternative to screen potential xenoestrogens in environment. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Estetrol, a Fetal Selective Estrogen Receptor Modulator, Acts on the Vagina of Mice through Nuclear Estrogen Receptor α Activation.

    PubMed

    Benoit, Thibaut; Valera, Marie-Cecile; Fontaine, Coralie; Buscato, Melissa; Lenfant, Francoise; Raymond-Letron, Isabelle; Tremollieres, Florence; Soulie, Michel; Foidart, Jean-Michel; Game, Xavier; Arnal, Jean-Francois

    2017-11-01

    The genitourinary syndrome of menopause has a negative impact on quality of life of postmenopausal women. The treatment of vulvovaginal atrophy includes administration of estrogens. However, oral estrogen treatment is controversial because of its potential risks on venous thrombosis and breast cancer. Estetrol (E4) is a natural estrogen synthesized exclusively during pregnancy by the human fetal liver and initially considered as a weak estrogen. However, E4 was recently evaluated in phase 1 to 2 clinical studies and found to act as an oral contraceptive in combination with a progestin, without increasing the level of coagulation factors. We recently showed that E4 stimulates uterine epithelial proliferation through nuclear estrogen receptor (ER) α, but failed to elicit endothelial responses. Herein, we first evaluated the morphological and functional impacts of E4 on the vagina of ovariectomized mice, and we determined the molecular mechanism mediating these effects. Vaginal epithelial proliferation and lubrication after stimulation were found to increase after E4 chronic treatment. Using a combination of pharmacological and genetic approaches, we demonstrated that these E4 effects on the vagina are mediated by nuclear ERα activation. Altogether, we demonstrate that the selective activation of nuclear ERα is both necessary and sufficient to elicit functional and structural effects on the vagina, and therefore E4 appears promising as a therapeutic option to improve vulvovaginal atrophy. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  6. COMPARISON OF FATHEAD MINNOW AND HUMAN ESTROGEN RECEPTOR BINDING TO ENDOCRINE DISRUPTING COMPOUNDS

    EPA Science Inventory

    Environmental estrogens have the potential to disrupt endocrine function in a myriad of species. However, in vitro assays designed to detect and characterize endocrine disrupting chemicals (EDCs) typically utilize mammalian estrogen receptors. Our overall objective is to charac...

  7. Steroid receptor coactivator-1 mediates estrogenic actions to prevent body weight gain in female mice

    USDA-ARS?s Scientific Manuscript database

    Estrogen receptor-alpha (ERalpha) expressed by hypothalamic proopiomelanocortin and steroidogenic factor-1 neurons largely mediates the antiobesity effects of estrogens in females. However, the critical molecular events that are coupled to ERalpha and mediate estrogenic effects on energy balance rem...

  8. Changes in estrogen receptor signaling alters the timekeeping system in male mice.

    PubMed

    Blattner, Margaret S; Mahoney, Megan M

    2015-11-01

    Circadian rhythms are modulated by steroid hormones; however, the mechanisms of this action are not fully understood, particularly in males. In females estradiol regulates activity level, pattern of expression, and free running period (tau). We tested the hypothesis that activity level and distribution in male mice includes both classical and "non-classical" actions of estrogens at the estrogen receptor subtype 1 (ESR1). We used transgenic mice with mutations in their estrogen response pathways: ESR1 knock-out (ERKO) mice lack the ability to respond to estrogens via ESR1. "Non-classical" estrogen receptor knock-in (NERKI) mice have an inserted ESR1 receptor with a mutation in the estrogen-response-element binding domain, allowing activation via non-genomic and second messenger pathways. Gonadectomized male NERKI, ERKO, and wildtype (WT) littermates were given oil, or low or high dose estradiol and daily activity parameters were quantified. Estradiol shortened the ratio of activity in the light relative to dark (LD ratio), shortened tau, advanced the time of activity onset, and altered responsiveness to light cues administered in the late subjective night, suggesting modulation by an ESR1-independent mechanism. Estradiol treatment in NERKI but not WT males altered the timing of activity onset, LD ratio, and the behavioral response to light cues. These results may represent disruptions in the balance of genomic/nongenomic or ESR1/ESR2 signaling pathways. We also found a significant genotype effect on total activity, LD ratio, tau, and activity duration. These data provide new information about the role of ESR1-dependent and independent signaling pathways on the timekeeping system in male mice. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Membrane Estrogen and HER-2 Receptors in Human Breast Cancer

    DTIC Science & Technology

    2002-07-01

    activation of G-proteins, adenylate cyclase, inositol phosphate, calcium homeostasis and/or MAP kinase. These interactions may promote phosphorylation of ER...of breast cancer cells and interact with transmembrane HER-2 growth factor receptors. Expression of HER-2 receptors occurs in many breast cancers...reports of significant cross-talk and interaction between erb B (HER) pathways and estrogen receptor signaling (3,24,27,34-36). It is generally held

  10. SPONTANEOUS AIRWAY HYPERRESPONSIVENESS IN ESTROGEN RECEPTOR-A DEFICIENT MICE

    EPA Science Inventory

    Rationale: Airway hyperresponsiveness is a critical feature of asthma. Substantial epidemiologic evidence supports a role for female sex hormones in modulating lung function and airway hyperresponsiveness in humans. Objectives: To examine the role of estrogen receptors in modulat...

  11. Estrogen action and prostate cancer

    PubMed Central

    Nelles, Jason L; Hu, Wen-Yang; Prins, Gail S

    2011-01-01

    Early work on the hormonal basis of prostate cancer focused on the role of androgens, but more recently estrogens have been implicated as potential agents in the development and progression of prostate cancer. In this article, we review the epidemiological, laboratory and clinical evidence that estrogen may play a causative role in human prostate cancer, as well as rodent and grafted in vivo models. We then review recent literature highlighting potential mechanisms by which estrogen may contribute to prostate cancer, including estrogenic imprinting and epigenetic modifications, direct genotoxicity, hyperprolactinemia, inflammation and immunologic changes, and receptor-mediated actions. We discuss the work performed so far separating the actions of the different known estrogen receptors (ERs), ERα and ERβ, as well as G-protein-coupled receptor 30 and their specific roles in prostate disease. Finally, we predict that future work in this field will involve more investigations into epigenetic changes, experiments using new models of hormonal dysregulation in developing human prostate tissue, and continued delineation of the roles of the different ER subtypes, as well as their downstream signaling pathways that may serve as therapeutic targets. PMID:21765856

  12. Evaluation of estrogen and G protein-coupled estrogen receptor 1 (GPER) levels in drug-naïve patients with attention deficit hyperactivity disorder (ADHD).

    PubMed

    Sahin, Nilfer; Altun, Hatice; Kurutaş, Ergül Belge; Fındıklı, Ebru

    2018-05-20

    Estrogen has a crucial role in the regulation of reproductive and neuroendocrine function and exerts its effects through two classes of receptors, nuclear and membrane estrogen receptors (mERs). G protein-coupled estrogen receptor 1 (GPER) is a member of mERs, and despite limited research on the levels of GPER in patients with psychiatric diseases, a role of GPER in such conditions has been suggested. Here we evaluated serum estrogen and GPER levels in children with attention deficit hyperactivity disorder (ADHD) in relation to their age- and gender-matched healthy controls. A total of 82 children were included in the study, 47 drug- naïve patients with ADHD (age: 6-12 years; male/female: 34/13) and 35 healthy controls (age: 6-12 years; male/female: 19/16). The subgroups according to ADHD types were inattentive, hyperactive/impulsive, and combined. Serum estrogen was measured using an immunoassay system, while serum GPER was determined using a commercial sandwich enzyme-linked immunosorbent assay kit. Estrogen levels in children with ADHD were similar as in control group, while GPER levels were significantly lower in ADHD group compared to controls (p < 0.05). Logistic regression analysis showed a significant association between GPER levels and ADHD (p < 0.05), and no association between estrogen levels and ADHD (p > 0.05). No significant differences were found in GPER and estrogen levels between ADHD subgroups (p > 0.05). To the best of our knowledge, this study is the first to investigate estrogen and GPER levels in ADHD. Our preliminary findings suggest a relationship between serum GPER levels and ADHD, and this should be further investigated.

  13. Extracellular matrix integrity: a possible mechanism for differential clinical effects among selective estrogen receptor modulators and estrogens?

    PubMed

    Cox, David A; Helvering, Leah M

    2006-03-09

    Recent gene microarray studies have illustrated heterogeneity in gene expression changes not only between estrogens and selective estrogen receptor modulators (SERMs), but also across different SERM molecules. In ovariectomized rats, this phenomenon was observed with respect to a number of genes involved in collagen turnover and extracellular matrix (ECM) integrity in the uterus and vaginal tissues. Preliminary mechanistic data suggest that these effects on ECM integrity may have relevance in the context of the effect of estrogens and some SERMs to increase the risk of pelvic organ prolapse and the incidence of urinary incontinence in postmenopausal women. Given the pivotal role of ECM integrity and collagen turnover in other tissues and disease states, these processes may provide a fruitful target for future research into the mechanisms for the heterogeneous pharmacology of estrogens and SERMs across different cell types and target tissues.

  14. The estrogen-related receptors and the adipocyte.

    PubMed

    Carnesecchi, Julie; Vanacker, Jean-Marc

    2013-08-01

    The estrogen-related receptors (ERRα, β, and γ) are orphan members of the nuclear receptor superfamily. ERRα and γ are highly expressed in tissues displaying elevated energy demands and are involved in several aspects of energetic metabolism, which they regulate mostly in association with members of the PGC-1 coactivator family. These activities have mostly been documented in the liver, heart, or skeletal muscle. ERRα and γ are also highly expressed in adipocytes. Their precise roles in this cell type are less documented, although published data indicate that they contribute to cell differentiation as well as functionality. This review describes these activities.

  15. The antiestrogen ICI 182,780 decreases the expression of estrogen receptor-alpha but has no effect on estrogen receptor-beta and androgen receptor in rat efferent ductules

    PubMed Central

    Oliveira, Cleida A; Nie, Rong; Carnes, Kay; Franca, Luiz R; Prins, Gail S; Saunders, Philippa TK; Hess, Rex A

    2003-01-01

    Background The antiestrogen ICI 182,780 has been used successfully as an alternative experimental model for the study of estrogen action in the rodent adult male reproductive tract. Although ICI 182,780 causes severe alterations in testicular and efferent ductule morphology and function, the effects on the expression of estrogen and androgen receptors in the male have not been shown. Methods In the present study, adult male rats were treated with ICI 182,780 for 7 to 150 days, to evaluate the time-response effects of the treatment on the pattern of ERα, ERβ and AR protein expression in the efferent ductules. The receptors were localized using immunohistochemistry. Results ERα, ERβ and AR have distinct cellular distribution in the testis and efferent ductules. Staining for ERα is nearly opposite of that for ERβ, as ERα shows an increase in staining intensity from proximal to distal efferent ductules, whereas ERβ shows the reverse. Androgen receptor follows that of ERα. ICI 182,780 caused a gradual but dramatic decrease in ERα expression in the testis and efferent ductules, but no change in ERβ and AR expression. Conclusions The differential response of ERα and ERβ proteins to ICI 182,780 indicates that these receptors are regulated by different mechanisms in the male reproductive tract. PMID:14613549

  16. Involvement of Epidermal Growth Factor Receptor Signaling in Estrogen Inhibition of Oocyte Maturation Mediated Through the G Protein-Coupled Estrogen Receptor (Gper) in Zebrafish (Danio rerio)1

    PubMed Central

    Peyton, Candace; Thomas, Peter

    2011-01-01

    Oocyte maturation (OM) in teleosts is under precise hormonal control by progestins and estrogens. We show here that estrogens activate an epidermal growth factor receptor (Egfr) signaling pathway in fully grown, denuded zebrafish (Danio rerio) oocytes through the G protein-coupled estrogen receptor (Gper; also known as GPR30) to maintain oocyte meiotic arrest in a germinal vesicle breakdown (GVBD) bioassay. A GPER-specific antagonist, G-15, increased spontaneous OM, indicating that the inhibitory estrogen actions on OM are mediated through Gper. Estradiol-17beta-bovine serum albumin, which cannot enter oocytes, decreased GVBD, whereas treatment with actinomycin D did not block estrogen's inhibitory effects, suggesting that estrogens act at the cell surface via a nongenomic mechanism to prevent OM. The intracellular tyrosine kinase (Src) inhibitor, PP2, blocked estrogen inhibition of OM. Expression of egfr mRNA and Egfr protein were detected in denuded zebrafish oocytes. The matrix metalloproteinase (MMP) inhibitor, ilomastat, which prevents the release of heparin-bound epidermal growth factor, increased spontaneous OM, whereas the MMP activator, interleukin-1alpha, decreased spontaneous OM. Moreover, inhibitors of EGFR (ErbB1) and extracellular-related kinase 1 and 2 (Erk1/2; official symbol Mapk3/1) increased spontaneous OM. In addition, estradiol-17beta and the GPER agonist, G-1, increased phosphorylation of Erk, and this was abrogated by simultaneous treatment with the EGFR inhibitor. Taken together, these results suggest that estrogens act through Gper to maintain meiotic arrest via an Src kinase-dependent G-protein betagamma subunit signaling pathway involving transactivation of egfr and phosphorylation of Mapk3/1. To our knowledge, this is the first evidence that EGFR signaling in vertebrate oocytes can prevent meiotic progression. PMID:21349822

  17. Targeted basic research to highlight the role of estrogen and estrogen receptors in the cardiovascular system.

    PubMed

    Dworatzek, Elke; Mahmoodzadeh, Shokoufeh

    2017-05-01

    Epidemiological, clinical and animal studies revealed that sex differences exist in the manifestation and outcome of cardiovascular disease (CVD). The underlying molecular mechanisms implicated in these sex differences are not fully understood. The reasons for sex differences in CVD are definitely multifactorial, but major evidence points to the contribution of sex steroid hormone, 17β-estradiol (E2), and its receptors, estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ). In this review, we summarize past and present studies that implicate E2 and ER as important determinants of sexual dimorphism in the physiology and pathophysiology of the heart. In particular, we give an overview of studies aimed to reveal the role of E2 and ER in the physiology of the observed sex differences in CVD using ER knock-out mice. Finally, we discuss recent findings from novel transgenic mouse models, which have provided new information on the sexual dimorphic roles of ER specifically in cardiomyocytes under pathological conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Not lost in translation: Emerging clinical importance of the G protein-coupled estrogen receptor GPER.

    PubMed

    Barton, Matthias

    2016-07-01

    It has been 20years that the G protein-coupled estrogen receptor (GPER) was cloned as the orphan receptor GPR30 from multiple cellular sources, including vascular endothelial cells. Here, I will provide an overview of estrogen biology and the historical background leading to the discovery of rapid vascular estrogen signaling. I will also review the recent advances in the understanding of the mechanisms underlying GPER function, its role in physiology and disease, some of the currently available GPER-targeting drugs approved for clinical use such as SERMs (selective estrogen receptor modulators) and SERDs (selective estrogen receptor downregulators). Many of currently used drugs such as tamoxifen, raloxifene, or faslodex™/fulvestrant were discovered targeting GPER many years after they had been introduced to the clinics for entirely different purposes. This has important implications for the clinical use of these drugs and their modes of action, which I have termed 'reverse translational medicine'. In addition, environmental pollutants known as 'endocrine disruptors' have been found to bind to GPER. This article also discusses recent evidence in these areas as well as opportunities in translational clinical medicine and GPER research, including medical genetics, personalized medicine, prevention, and its theranostic use. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. The Distinct Effects of Estrogen and Hydrostatic Pressure on Mesenchymal Stem Cells Differentiation: Involvement of Estrogen Receptor Signaling.

    PubMed

    Zhao, Ying; Yi, Fei-Zhou; Zhao, Yin-Hua; Chen, Yong-Jin; Ma, Heng; Zhang, Min

    2016-10-01

    This study aimed to investigate the differential and synergistic effects of mechanical stimulation and estrogen on the proliferation and osteogenic or chondrogenic differentiation potential of bone marrow mesenchymal stem cells (BMSCs) and the roles of estrogen receptor (ER) in them. BMSCs were isolated and cultured using the whole bone marrow adherence method, and flow cytometry was used to identify the surface marker molecules of BMSCs. Cells were pre-treated with 1 nM 17β-estradiol or 1 nM of the estrogen receptor antagonist tamoxifen. Then, the cells were stimulated with hydrostatic pressure. Assessment included flow cytometry analysis of the cell cycle; immunofluorescent staining for F-actin; protein quantification for MAPK protein; and mRNA analysis for Col I, OCN, OPN and BSP after osteogenic induction and Sox-9, Aggrecan and Col-II after chondrogenic induction. Hydrostatic pressure (90 kPa/1 h) and 1 nM 17β-estradiol enhanced the cellular proliferation ability and the cytoskeleton activity but without synergistic biological effects. Estrogen activated ERKs and JNKs simultaneously and promoted the osteogenic differentiation, whereas the pressure just caused JNK-1/2 activation and promoted the chondrogenic differentiation of BMSCs. Estrogen had antagonism effect on chondrogenic promotion of hydrostatic pressure. Mechanobiological effects of hydrostatic pressure are closely associated with ERα activity. MAPK molecules and F-actin were likely to be important mediator molecules in the ER-mediated mechanotransduction of BMSCs.

  20. Quantitative RT-PCR analysis of estrogen receptor gene expression in laser microdissected prostate cancer tissue.

    PubMed

    Walton, Thomas J; Li, Geng; McCulloch, Thomas A; Seth, Rashmi; Powe, Desmond G; Bishop, Michael C; Rees, Robert C

    2009-06-01

    Real-time quantitative RT-PCR analysis of laser microdissected tissue is considered the most accurate technique for determining tissue gene expression. The discovery of estrogen receptor beta (ERbeta) has focussed renewed interest on the role of estrogen receptors in prostate cancer, yet few studies have utilized the technique to analyze estrogen receptor gene expression in prostate cancer. Fresh tissue was obtained from 11 radical prostatectomy specimens and from 6 patients with benign prostate hyperplasia. Pure populations of benign and malignant prostate epithelium were laser microdissected, followed by RNA isolation and electrophoresis. Quantitative RT-PCR was performed using primers for androgen receptor (AR), estrogen receptor beta (ERbeta), estrogen receptor alpha (ERalpha), progesterone receptor (PGR) and prostate specific antigen (PSA), with normalization to two housekeeping genes. Differences in gene expression were analyzed using the Mann-Whitney U-test. Correlation coefficients were analyzed using Spearman's test. Significant positive correlations were seen when AR and AR-dependent PSA, and ERalpha and ERalpha-dependent PGR were compared, indicating a representative population of RNA transcripts. ERbeta gene expression was significantly over-expressed in the cancer group compared with benign controls (P < 0.01). In contrast, PGR expression was significantly down-regulated in the cancer group (P < 0.05). There were no significant differences in AR, ERalpha or PSA expression between the groups. This study represents the first to show an upregulation of ERbeta gene expression in laser microdissected prostate cancer specimens. In concert with recent studies the findings suggest differential production of ERbeta splice variants, which may play important roles in the genesis of prostate cancer. (c) 2009 Wiley-Liss, Inc.

  1. Synthesis and biological evaluation of guanylhydrazone coactivator binding inhibitors for the estrogen receptor.

    PubMed

    LaFrate, Andrew L; Gunther, Jillian R; Carlson, Kathryn E; Katzenellenbogen, John A

    2008-12-01

    Most patients with hormone-responsive breast cancer eventually develop resistance to traditional antiestrogens such as tamoxifen, and this has become a major obstacle in their treatment. We prepared and characterized the activity of a series of 16 guanylhydrazone small molecules that are designed to block estrogen receptor (ER) activity through a non-traditional mechanism, by directly interfering with coactivator binding to agonist-liganded ER. The inhibitory activity of these compounds was determined in cell-based transcription assays using ER-responsive reporter gene and mammalian two-hybrid assays. Several of the compounds gave IC(50) values in the low micromolar range. Two secondary assays were used to confirm that these compounds were acting through the proposed non-traditional mode of estrogen inhibitory action and not as conventional antagonists at the ligand binding site.

  2. Dilation of epicardial coronary arteries by the G protein-coupled estrogen receptor agonists G-1 and ICI 182,780.

    PubMed

    Meyer, Matthias R; Baretella, Oliver; Prossnitz, Eric R; Barton, Matthias

    2010-01-01

    Endogenous estrogens protect from coronary artery disease in premenopausal women, but the mechanisms involved are only partly understood. This study investigated whether activation of the novel G protein-coupled estrogen receptor (GPER, formerly known as GPR30) affects coronary artery tone, and whether this is affected by concomitant blockade of estrogen receptors (ER) alpha and beta. Rings of epicardial porcine coronary arteries suspended in organ chambers were precontracted with prostaglandin F(2)alpha, and direct effects of G-1 (GPER agonist) and ICI 182,780 (GPER agonist and ERalpha/ERbeta antagonist) were determined. In addition, indirect effects on contractility to endothelin-1 and serotonin (a vasoconstrictor released from aggregating platelets during acute myocardial infarction) were assessed. ICI 182,780 and G-1 caused acute dilation of coronary arteries to a comparable degree (p < 0.05 vs. solvent control). Both GPER agonists attenuated contractions to endothelin-1 (p < 0.05 vs. ethanol), but not to serotonin (n.s.). In summary, these findings provide evidence for direct and indirect coronary artery dilator effects of GPER independent of ERalpha and ERbeta, and are the first demonstration of arterial vasodilation in response to ICI 182,780. Copyright 2010 S. Karger AG, Basel.

  3. Internalization of a C17α-alkynylestradiol-porphyrin conjugate into estrogen receptor positive MCF-7 breast cancer cells.

    PubMed

    Sadler, Sara; Persons, Kelly S; Jones, Graham B; Ray, Rahul

    2011-08-01

    We hypothesized that expression of nuclear estrogen receptor (ER) in hormone-sensitive breast cancer cells could be harnessed synergistically with the tumor-accumulating effect of porphyrins to selectively deliver estrogen-porphyrin conjugates into breast tumor cells, and preferentially kill tumor cells upon exposure to visible light. In this study we synthesized a conjugate of C(17α)-alkynylestradiol and pyropheophorbide and demonstrated that this conjugate is internalized by ER-positive MCF-7 cells while pyropheophorbide did not, suggesting an ER-mediated uptake and internalization of the conjugate by incipient nuclear ER in MCF-7 cells. This study is a direct demonstration of our hypothesis about ER-mediated internalization of estrogen-porphyrin conjugates. Copyright © 2011. Published by Elsevier Ltd.

  4. CERAPP: Collaborative Estrogen Receptor Activity Prediction ...

    EPA Pesticide Factsheets

    Humans potentially are exposed to thousands of man-made chemicals in the environment. Some chemicals mimic natural endocrine hormones and, thus, have the potential to be endocrine disruptors. Many of these chemicals never have been tested for their ability to interact with the estrogen receptor (ER). Risk assessors need tools to prioritize chemicals for assessment in costly in vivo tests, for instance, within the EPA Endocrine Disruptor Screening Program. Here, we describe a large-scale modeling project called CERAPP (Collaborative Estrogen Receptor Activity Prediction Project) demonstrating the efficacy of using predictive computational models on high-throughput screening data to screen thousands of chemicals against the ER. CERAPP combined multiple models developed in collaboration among 17 groups in the United States and Europe to predict ER activity of a common set of 32,464 chemical structures. Quantitative structure-activity relationship models and docking approaches were employed, mostly using a common training set of 1677 compounds provided by EPA, to build a total of 40 categorical and 8 continuous models for binding, agonist, and antagonist ER activity. All predictions were tested using an evaluation set of 7522 chemicals collected from the literature. To overcome the limitations of single models, a consensus was built weighting models using a scoring function (0 to 1) based on their accuracies. Individual model scores ranged from 0.69 to 0.85, showing

  5. Identification and Biological Evaluation of Coactivator Binding Inhibitors for the Estrogen Receptor

    ERIC Educational Resources Information Center

    Gunther, Jillian Rebecca

    2009-01-01

    The physiologic effects of estrogen action through the estrogen receptor (ER) are widespread, as this hormone exerts actions in both reproductive (e.g., uterus) and non-reproductive (e.g., bone, brain) tissues in both men and women. As such, the regulation of the activity of this ligand-activated transcription factor is highly relevant to the…

  6. G Protein-coupled Estrogen Receptor Protects from Atherosclerosis

    PubMed Central

    Meyer, Matthias R.; Fredette, Natalie C.; Howard, Tamara A.; Hu, Chelin; Ramesh, Chinnasamy; Daniel, Christoph; Amann, Kerstin; Arterburn, Jeffrey B.; Barton, Matthias; Prossnitz, Eric R.

    2014-01-01

    Coronary atherosclerosis and myocardial infarction in postmenopausal women have been linked to inflammation and reduced nitric oxide (NO) formation. Natural estrogen exerts protective effects on both processes, yet also displays uterotrophic activity. Here, we used genetic and pharmacologic approaches to investigate the role of the G protein-coupled estrogen receptor (GPER) in atherosclerosis. In ovary-intact mice, deletion of gper increased atherosclerosis progression, total and LDL cholesterol levels and inflammation while reducing vascular NO bioactivity, effects that were in some cases aggravated by surgical menopause. In human endothelial cells, GPER was expressed on intracellular membranes and mediated eNOS activation and NO formation, partially accounting for estrogen-mediated effects. Chronic treatment with G-1, a synthetic, highly selective small molecule agonist of GPER, reduced postmenopausal atherosclerosis and inflammation without uterotrophic effects. In summary, this study reveals an atheroprotective function of GPER and introduces selective GPER activation as a novel therapeutic approach to inhibit postmenopausal atherosclerosis and inflammation in the absence of uterotrophic activity. PMID:25532911

  7. GPER Mediates Non-Genomic Effects of Estrogen.

    PubMed

    Pupo, Marco; Maggiolini, Marcello; Musti, Anna Maria

    2016-01-01

    Estrogens are important modulators of a broad spectrum of physiological functions in humans. However, despite their beneficial actions, a number of lines of evidence correlate the sustained exposure to exogenous estrogen with increased risk of the onset of various cancers. Mainly these steroid hormones induce their effects by binding and activating estrogen receptors (ERα and ERβ). These receptors belong to the family of ligand-regulated transcription factors, and upon activation they regulate the expression of different target genes by binding directly to specific DNA sequences. On the other hand, in recent years it has become clear that the G protein-coupled estrogen receptor 30 (GPR30/GPER) is able to mediate non-genomic action of estrogens in different cell contexts. In particular, GPER has been shown to specifically bind estrogens, and in turn to functionally cross-react with diverse cell signaling systems such as the epidermal growth factor receptor (EGFR) pathway, the Notch signaling pathway and the mitogen-activated protein kinases (MAPK) pathway. In this chapter we will present some of the different experimental techniques currently used to demonstrate the functional role of GPER in mediating non-genomic actions of estrogens, such as the dual luciferase assay, assessment of the involvement of GPER in the stimulation of cell migration in breast cancer cell lines and in cancer-associated fibroblasts, and chromatin immunoprecipitation assay. Overall, the experimental procedures described herein represent key instruments for assessing the biological role of GPER in mediating non-genomic signals of estrogen.

  8. Formononetin promotes angiogenesis through the estrogen receptor alpha-enhanced ROCK pathway.

    PubMed

    Li, Shang; Dang, Yuanye; Zhou, Xuelin; Huang, Bin; Huang, Xiaohui; Zhang, Zherui; Kwan, Yiu Wa; Chan, Shun Wan; Leung, George Pak Heng; Lee, Simon Ming Yuen; Hoi, Maggie Pui Man

    2015-11-16

    Formononetin is an isoflavone that has been shown to display estrogenic properties and induce angiogenesis activities. However, the interrelationship between the estrogenic properties and angiogenesis activities of formononetin are not well defined. In the present study, docking and enzymatic assay demonstrated that formononetin displayed direct binding to the ligand-binding domain (LBD) of estrogen receptor alpha (ERα) with an agonistic property. Results from Human Umbilical Vein Endothelial Cells (HUVEC) by using real-time migration xCELLigence system, immunofluorescence and western blotting provided strong evidences of formononetin induced endothelial cell migration and dramatic actin cytoskeleton spatial modification through ERα-enhanced-ROCK-II/MMP2/9 signaling pathways. In addition, results from co-immunoprecipitation suggested formononetin induced cell migration via recruiting of ERα/ROCK-II activated complex formation. More interestingly, in zebrafish embryo we observed that formononetin significantly promoted angiogenic sproutings in the subintestinal vessels (SIVs) that could be completely abolished by ROCK inhibitor. In this study, we elucidated the underlying mechanisms that formononetin produced proangiogenesis effects through an ERα-enhanced ROCK-II signaling pathways. Results from the present study also expand our knowledge about the enigmatic underlying mechanisms of phytoestrogenic compounds in the promotion of angiogenesis in relation to ERα and ROCK interaction in endothelial cells and their relationship with actin assembly and cell migration.

  9. The human oxytocin gene promoter is regulated by estrogens.

    PubMed

    Richard, S; Zingg, H H

    1990-04-15

    Gonadal steroids affect brain function primarily by altering the expression of specific genes, yet the specific mechanisms by which neuronal target genes undergo such regulation are unknown. Recent evidence suggests that the expression of the neuropeptide gene for oxytocin (OT) is modulated by estrogens. We therefore examined the possibility that this regulation occurred via a direct interaction of the estrogen-receptor complex with cis-acting elements flanking the OT gene. DNA-mediated gene transfer experiments were performed using Neuro-2a neuroblastoma cells and chimeric plasmids containing portions of the human OT gene 5'-glanking region linked to the chloramphenicol acetyltransferase gene. We identified a 19-base pair region located at -164 to -146 upstream of the transcription start site which is capable of conferring estrogen responsiveness to the homologous as well as to a heterologous promoter. The hormonal response is strictly dependent on the presence of intracellular estrogen receptors, since estrogen induced stimulation occurred only in Neuro-2a cells co-transfected with an expression vector for the human estrogen receptor. The identified region contains a novel imperfect palindrome (GGTGACCTTGACC) with sequence similarity to other estrogen response elements (EREs). To define cis-acting elements that function in synergism with the ERE, sequences 3' to the ERE were deleted, including the CCAAT box, two additional motifs corresponding to the right half of the ERE palindrome (TGACC), as well as a CTGCTAA heptamer similar to the "elegans box" found in Caenorhabditis elegans. Interestingly, optimal function of the identified ERE was fully independent of these elements and only required a short promoter region (-49 to +36). Our studies define a molecular mechanism by which estrogens can directly modulate OT gene expression. However, only a subset of OT neurons are capable of binding estrogens, therefore, direct action of estrogens on the OT gene may be

  10. Estrogen modulates sexually dimorphic contextual fear extinction in rats through estrogen receptor beta.

    PubMed

    Chang, Yao-Ju; Yang, Chih-Hao; Liang, Ying-Ching; Yeh, Che-Ming; Huang, Chiung-Chun; Hsu, Kuei-Sen

    2009-11-01

    Females and males are different in brain and behavior. These sex differences occur early during development due to a combination of genetic and hormonal factors and continue throughout the lifespan. Previous studies revealed that male rats exhibited significantly higher levels of contextual fear memory than female rats. However, it remains unknown whether a sex difference exists in the contextual fear extinction. To address this issue, male, normally cycling female, and ovariectomized (OVX) female Sprague-Dawley rats were subjected to contextual fear conditioning and extinction trials. Here we report that although male rats exhibited higher levels of freezing than cycling female rats after contextual fear conditioning, female rats subjected to conditioning in the proestrus and estrus stage exhibited an enhancement of fear extinction than male rats. An estrogen receptor (ER) beta agonist diarylpropionitrile but not an ERalpha agonist propyl-pyrazole-triol administration also enhanced extinction of contextual fear in OVX female rats, suggesting that estrogen-mediated facilitation of extinction involves the activation of ERbeta. Intrahippocampal injection of estradiol or diarylpropionitrile before extinction training in OVX female rats remarkably reduced the levels of freezing response during extinction trials. In addition, the locomotion or anxiety state of female rats does not vary across the ovarian cycle. These results reveal a crucial role for estrogen in mediating sexually dimorphic contextual fear extinction, and that estrogen-mediated enhancement of fear extinction involves the activation of ERbeta.

  11. Estrogen receptors in skeletal metabolism: lessons from genetically modified models of receptor function.

    PubMed

    McCauley, Laurie K; Tözüm, Tolga F; Rosol, Thomas J

    2002-01-01

    Estrogens have long been known to be important for skeletal homeostasis, but their precise mechanisms of action in bone are still unclear. Mice with targeted deletions of the estrogen receptors alpha (ERalpha) and beta (ERbeta) have been generated by two research groups and several studies performed characterizing the phenotype of ERalpha knockout (ERKOalpha), ERbeta knockout (ERKObeta), or double deletion of ERalpha and ERbeta (DERKO) mice. Initial studies reported a reduction in bone mineral density in male ERKOalpha mice. More extensive analyses have been puzzling, likely because of compensatory mechanisms in ERKO mice. Furthermore, the existence of a third ER continues to be a potential explanation for some actions of estrogen in bone. Other rodent models, including the testicular feminized mouse and rat, the aromatase knockout mouse, and a rat with a dominant negative ER mutation, have added information regarding estrogen's actions in bone. This review summarizes many reports characterizing available rodent models with genetic alterations relevant to estrogen action. The sum of these reports suggests that the ERbeta is not highly protective in bone because loss of its function results in minimal alterations in the skeleton. Furthermore, loss of both the ERalpha and the ERbeta does not account for loss of estrogen action in bone, because the impact of DERKO is seemingly not as great as the impact of gonadectomy on the skeleton. Finally, through studies of ERKO mice and other rodent models of altered sex steroid action, it appears that estrogen may be more protective in the skeleton than androgens.

  12. Raloxifene increases prefrontal activity during emotional inhibition in schizophrenia based on estrogen receptor genotype.

    PubMed

    Kindler, Jochen; Weickert, Cynthia Shannon; Schofield, Peter R; Lenroot, Rhoshel; Weickert, Thomas W

    2016-12-01

    People with schizophrenia show decreased prefrontal cortex (PFC) activity during emotional response inhibition, a cognitive process sensitive to hormonal influences. Raloxifene, a selective estrogen receptor modulator, binds estrogen receptor alpha (ESR-α), improves memory, attention and normalizes cortical and hippocampal activity during learning and emotional face recognition in schizophrenia. Here, we tested the extent to which raloxifene restores neuronal activity during emotional response inhibition in schizophrenia. Since genetic variation in estrogen receptor alpha (ESR-1) determines cortical ESR-α production and correlates with cognition, we also predicted that genetic ESR-1 variation would differentially relate to increased cortical activity by raloxifene administration. Thirty people with schizophrenia participated in a thirteen-week randomized, double-blind, placebo-controlled, cross-over adjunctive treatment trial of raloxifene administered at 120mg/day. Effects of raloxifene on brain activation were assessed based on ESR-1 genotype using functional magnetic resonance imaging during emotional word inhibition. Raloxifene increased PFC activity during inhibition of response to negative words and the raloxifene related increased PFC activity was greater in patients homozygous for ESR-1 rs9340799 AA relative to G carriers. Comparison to 23 healthy controls demonstrated that PFC activity of people with schizophrenia receiving raloxifene was more similar to controls than to their own brain activity during placebo. Estrogen receptor modulation by raloxifene restores PFC activity during emotional response inhibition in schizophrenia and ESR-1 genotype predicts degree of increased neural activity in response to raloxifene. While these preliminary results require replication, they suggest the potential for personalized pharmacotherapy using ESR-1 and estrogen receptor targeting compounds in schizophrenia. Crown Copyright © 2016. Published by Elsevier B

  13. Recent advance in the design of small molecular modulators of estrogen-related receptors.

    PubMed

    Lu, Xiaoyun; Peng, Lijie; Lv, Man; ding, Ke

    2012-01-01

    The estrogen-related receptors (ERRs), comprising ERRα, ERRβ and ERRγ, are the members of the nuclear receptor superfamily, which have been functionally implicated in estrogen signal pathway in various patterns. However, no natural ligand of ERRs has been identified to data, so identification of the synthetic modulators (inverse agonist and agonist) of ERRs would be highly effective in the treatment of estrogen-related pathologies, such as diabetes, breast cancer and osteoporosis. This review summarizes the structures and biological functions of ERR subtypes, and the progress in designing the small molecular modulators of ERRs as well as the detailed description of available co-crystal structures of the LBD of ERRs in three distinct states: unligand, inverse agonist bound, and agonist bound.

  14. Design and structure of stapled peptides binding to estrogen receptors.

    PubMed

    Phillips, Chris; Roberts, Lee R; Schade, Markus; Bazin, Richard; Bent, Andrew; Davies, Nichola L; Moore, Rob; Pannifer, Andrew D; Pickford, Andrew R; Prior, Stephen H; Read, Christopher M; Scott, Andrew; Brown, David G; Xu, Bin; Irving, Stephen L

    2011-06-29

    Synthetic peptides that specifically bind nuclear hormone receptors offer an alternative approach to small molecules for the modulation of receptor signaling and subsequent gene expression. Here we describe the design of a series of novel stapled peptides that bind the coactivator peptide site of estrogen receptors. Using a number of biophysical techniques, including crystal structure analysis of receptor-stapled peptide complexes, we describe in detail the molecular interactions and demonstrate that all-hydrocarbon staples modulate molecular recognition events. The findings have implications for the design of stapled peptides in general.

  15. An energetic orphan in an endocrine tissue: a revised perspective of the function of estrogen receptor-related receptor alpha in bone and cartilage.

    PubMed

    Bonnelye, Edith; Aubin, Jane E

    2013-02-01

    Estrogen receptor-related receptor alpha (ERRα) is an orphan nuclear receptor with sequence homology to the estrogen receptors, ERα/β, but it does not bind estrogen. ERRα not only plays a functional role in osteoblasts but also in osteoclasts and chondrocytes. In addition, the ERRs, including ERRα, can be activated by coactivators such as peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC1α and β) and are implicated in adipogenesis, fatty acid oxidation, and oxidative stress defense, suggesting that ERRα-through its activity in bone resorption and adipogenesis--may regulate the insulin and leptin pathways and contribute to aging-related changes in bone and cartilage. In this review, we discuss data on ERRα and its cellular and molecular modes of action, which have broad implications for considering the potential role of this orphan receptor in cartilage and bone endocrine function, on whole-organism physiology, and in the bone aging process. Copyright © 2013 American Society for Bone and Mineral Research.

  16. Discovery of estrogen receptor α modulators from natural compounds in Si-Wu-Tang series decoctions using estrogen-responsive MCF-7 breast cancer cells.

    PubMed

    Liu, Li; Ma, Hongyue; Tang, Yuping; Chen, Wenxing; Lu, Yin; Guo, Jianming; Duan, Jin-Ao

    2012-01-01

    The binding between the estrogen receptor α (ER-α) and a variety of compounds in traditional Chinese formulae, Si-Wu-Tang (SWT) series decoctions, was studied using a stably-transfected human breast cancer cell line (MVLN). In 38 compounds tested from SWT series decoctions, the estrogen-like activity of 22 compounds was above 60% in 20 μg mL(-1). Furthermore, theoretical affinity of these compounds was certificated using the functional virtual screen of ER-α modulators by FlexX-Pharm. The accuracy of functional virtual screening of ER-α modulators could reach to 77.27%. The results showed that some compounds, such as organic acids and flavones in SWT series decoctions could be used as selective estrogen receptor modulators (SERMs) and could be selected for further development as potential agents for estrogen related diseases. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Brain aromatase (Cyp19A2) and estrogen receptors, in larvae and adult pejerrey fish Odontesthes bonariensis: Neuroanatomical and functional relations

    USGS Publications Warehouse

    Strobl-Mazzulla, P. H.; Lethimonier, C.; Gueguen, M.M.; Karube, M.; Fernandino, J.I.; Yoshizaki, G.; Patino, R.; Strussmann, C.A.; Kah, O.; Somoza, G.M.

    2008-01-01

    Although estrogens exert many functions on vertebrate brains, there is little information on the relationship between brain aromatase and estrogen receptors. Here, we report the cloning and characterization of two estrogen receptors, ?? and ??, in pejerrey. Both receptors' mRNAs largely overlap and were predominantly expressed in the brain, pituitary, liver, and gonads. Also brain aromatase and estrogen receptors were up-regulated in the brain of estradiol-treated males. In situ hybridization was performed to study in more detail, the distribution of the two receptors in comparison with brain aromatase mRNA in the brain of adult pejerrey. The estrogen receptors' mRNAs exhibited distinct but partially overlapping patterns of expression in the preoptic area and the mediobasal hypothalamus, as well as in the pituitary gland. Moreover, the estrogen receptor ??, but not ??, were found to be expressed in cells lining the preoptic recess, similarly as observed for brain aromatase. Finally, it was shown that the onset expression of brain aromatase and both estrogen receptors in the head of larvae preceded the morphological differentiation of the gonads. Because pejerrey sex differentiation is strongly influenced by temperature, brain aromatase expression was measured during the temperature-sensitive window and was found to be significantly higher at male-promoting temperature. Taken together these results suggest close neuroanatomical and functional relationships between brain aromatase and estrogen receptors, probably involved in the sexual differentiation of the brain and raising interesting questions on the origin (central or peripheral) of the brain aromatase substrate. ?? 2008 Elsevier Inc.

  18. G-Protein-Coupled Estrogen Receptor (GPER) and Sex-Specific Metabolic Homeostasis.

    PubMed

    Sharma, Geetanjali; Prossnitz, Eric R

    2017-01-01

    Obesity and metabolic syndrome display disparate prevalence and regulation between males and females. Human, as well as rodent, females with regular menstrual/estrous cycles exhibit protection from weight gain and associated chronic diseases. These beneficial effects are predominantly attributed to the female hormone estrogen, specifically 17β-estradiol (E2). E2 exerts its actions via multiple receptors, nuclear and extranuclear estrogen receptor (ER) α and ERβ, and the G-protein-coupled estrogen receptor (GPER, previously termed GPR30). The roles of GPER in metabolic homeostasis are beginning to emerge but are complex and remain unclear. The discovery of GPER-selective pharmacological agents (agonists and antagonists) and the availability of GPER knockout mice have significantly enhanced our understanding of the functions of GPER in normal physiology and disease. GPER action manifests pleiotropic effects in metabolically active tissues such as the pancreas, adipose, liver, and skeletal muscle. Cellular and animal studies have established that GPER is involved in the regulation of body weight, feeding behavior, inflammation, as well as glucose and lipid homeostasis. GPER deficiency leads to increased adiposity, insulin resistance, and metabolic dysfunction in mice. In contrast, pharmacologic stimulation of GPER in vivo limits weight gain and improves metabolic output, revealing a promising novel therapeutic potential for the treatment of obesity and diabetes.

  19. Estrogen-Induced Developmental Disorders of the Rat Penis Involve Both Estrogen Receptor (ESR)- and Androgen Receptor (AR)-Mediated Pathways1

    PubMed Central

    Goyal, H.O.; Braden, T.D.; Williams, C.S.; Williams, J.W.

    2009-01-01

    This study tested the hypothesis that the estrogen receptor (ESR) pathway, androgen receptor (AR) pathway, or both mediate estrogen-induced developmental penile disorders. Rat pups received diethylstilbestrol (DES), with or without the ESR antagonist ICI 182,780 (ICI) or the AR agonist dihydrotestosterone (DHT) or testosterone (T), from Postnatal Days 1 to 6. Testicular T concentration, penile morphology and morphometry, and/or fertility was determined at age 7, 28, or 150 days. DES treatment alone caused 90% reduction in the neonatal intratesticular T surge; this reduction was prevented by ICI coadministration, but not by DHT or T coadministration. Unlike the T surge, coadministration of ICI and coadministration of DHT or T mitigated penile deformities and loss of fertility. Generally, ICI, DHT, or T treatment alone did not alter penile morphology; however, fertility was 20% that of controls in ICI-treated rats vs. 70%–90% in DHT- or T-treated rats. The lower fertility in the rats treated with ICI alone could be due to altered sexual behavior, as these males did not deposit vaginal plugs. In conclusion, observations that both an ESR antagonist and AR agonists prevent penile deformities and infertility suggest that both pathways are involved in estrogen-induced penile disorders. Observations that coadministration of ICI, but not DHT or T, prevents the DES-induced reduction in the neonatal T surge suggest that, although ICI exerts its mitigating effect both at the level of Leydig cells and penile stromal cells, DHT and T do so only at the level of stromal cells. PMID:19420389

  20. Integration of Nuclear- and Extranuclear-Initiated Estrogen Receptor Signaling in Breast Cancer Cells

    ERIC Educational Resources Information Center

    Madak Erdogan, Zeynep

    2009-01-01

    Estrogenic hormones exert their effects through binding to Estrogen Receptors (ERs), which work in concert with coregulators and extranuclear signaling pathways to control gene expression in normal as well as cancerous states, including breast tumors. In this thesis, we have used multiple genome-wide analysis tools to elucidate various ways that…

  1. Noninvasive detection of activating estrogen receptor 1 (ESR1) mutations in estrogen receptor-positive metastatic breast cancer.

    PubMed

    Guttery, David S; Page, Karen; Hills, Allison; Woodley, Laura; Marchese, Stephanie D; Rghebi, Basma; Hastings, Robert K; Luo, Jinli; Pringle, J Howard; Stebbing, Justin; Coombes, R Charles; Ali, Simak; Shaw, Jacqueline A

    2015-07-01

    Activating mutations in the estrogen receptor 1 (ESR1) gene are acquired on treatment and can drive resistance to endocrine therapy. Because of the spatial and temporal limitations of needle core biopsies, our goal was to develop a highly sensitive, less invasive method of detecting activating ESR1 mutations via circulating cell-free DNA (cfDNA) and tumor cells as a "liquid biopsy." We developed a targeted 23-amplicon next-generation sequencing (NGS) panel for detection of hot-spot mutations in ESR1, phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA), tumor protein p53 (TP53), fibroblast growth factor receptor 1 (FGFR1), and fibroblast growth factor receptor 2 (FGFR2) in 48 patients with estrogen receptor-α-positive metastatic breast cancer who were receiving systemic therapy. Selected mutations were validated using droplet digital PCR (ddPCR). Nine baseline cfDNA samples had an ESR1 mutation. NGS detected 3 activating mutations in ESR1, and 3 hot-spot mutations in PIK3CA, and 3 in TP53 in baseline cfDNA, and the ESR1 p.D538G mutation in 1 matched circulating tumor cell sample. ddPCR analysis was more sensitive than NGS and identified 6 additional baseline cfDNA samples with the ESR1 p.D538G mutation at a frequency of <1%. In serial blood samples from 11 patients, 4 showed changes in cfDNA, 2 with emergence of a mutation in ESR1. We also detected a low frequency ESR1 mutation (1.3%) in cfDNA of 1 primary patient who was thought to have metastatic disease but was clear by scans. Early identification of ESR1 mutations by liquid biopsy might allow for cessation of ineffective endocrine therapies and switching to other treatments, without the need for tissue biopsy and before the emergence of metastatic disease. © 2015 American Association for Clinical Chemistry.

  2. Glyceollin, a novel regulator of mTOR/p70S6 in estrogen receptor positive breast cancer

    USDA-ARS?s Scientific Manuscript database

    An estimated 70% of breast cancer tumors utilize estrogen receptor (ER) signaling to maintain tumorigenesis, and targeting of the estrogen receptor is a common method of treatment for these tumor types. However, ER-positive (+) breast cancers often acquire drug resistant or altered ER activity in r...

  3. Glyphosate induces human breast cancer cells growth via estrogen receptors.

    PubMed

    Thongprakaisang, Siriporn; Thiantanawat, Apinya; Rangkadilok, Nuchanart; Suriyo, Tawit; Satayavivad, Jutamaad

    2013-09-01

    Glyphosate is an active ingredient of the most widely used herbicide and it is believed to be less toxic than other pesticides. However, several recent studies showed its potential adverse health effects to humans as it may be an endocrine disruptor. This study focuses on the effects of pure glyphosate on estrogen receptors (ERs) mediated transcriptional activity and their expressions. Glyphosate exerted proliferative effects only in human hormone-dependent breast cancer, T47D cells, but not in hormone-independent breast cancer, MDA-MB231 cells, at 10⁻¹² to 10⁻⁶M in estrogen withdrawal condition. The proliferative concentrations of glyphosate that induced the activation of estrogen response element (ERE) transcription activity were 5-13 fold of control in T47D-KBluc cells and this activation was inhibited by an estrogen antagonist, ICI 182780, indicating that the estrogenic activity of glyphosate was mediated via ERs. Furthermore, glyphosate also altered both ERα and β expression. These results indicated that low and environmentally relevant concentrations of glyphosate possessed estrogenic activity. Glyphosate-based herbicides are widely used for soybean cultivation, and our results also found that there was an additive estrogenic effect between glyphosate and genistein, a phytoestrogen in soybeans. However, these additive effects of glyphosate contamination in soybeans need further animal study. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Expression of the estrogen receptors and steroidogenic enzymes involved in estradiol formation in the monkey vagina.

    PubMed

    Bertin, Jonathan; Ouellet, Johanne; Dury, Alain Yves; Pelletier, Georges; Labrie, Fernand

    2014-11-01

    Estrogens are well recognized to have beneficial effects on vulvovaginal atrophy because of menopause. The distribution of estrogen receptors and enzymes responsible for estradiol (E2) formation within the vagina may provide insight into how dehydroepiandrosterone, a precursor of both estrogens and androgens, improves vulvovaginal atrophy. The purpose of the study was to determine where the steroidogenic enzymes responsible for E2 formation as well as estrogen receptors are localized in vaginal specimens collected from cynomolgus monkeys (Macaca fascicularis), the closest model to the human. HSD3B1, HSD17B1, HSD17B5, HSD17B12, aromatase (CYP19A1), estrogen receptor (ER)-α, and ER-β were measured or localized by quantitative real-time polymerase chain reaction, immunohistochemistry, and immunofluorescence. Estrogens were quantified by liquid chromatography/tandem mass spectrometry. All steroidogenic enzymes and estrogen receptors are localized mainly in the superficial layer of the stratified squamous epithelium, blood vessel walls, and muscle fibers of the vagina. Immunolabeling of HSD17B5 and HSD17B12 shows that these enzymes are uniformly distributed from the basal membrane to the superficial keratinized cells, whereas HSD3B1 and aromatase are particularly localized in the outer (external) portion of the epithelial layer. ER-α and ER-β are also distributed within the vaginal epithelium, with expression especially elevated at the basal membrane level. The enzymes responsible for E2 formation as well as ERs are expressed mainly in the superficial layer of the stratified epithelium as well as the muscle layer of the vagina. The present data provide morphologic and biochemical support for the role of local dehydroepiandrosterone transformation into estrogens in regulating epithelial cell maturation, pH, fluid secretion, smooth muscle activity, and blood flow regulation in the primate vagina. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Testosterone and 17β-estradiol have opposite effects on podocyte apoptosis that precedes glomerulosclerosis in female estrogen receptor knockout mice

    PubMed Central

    Doublier, Sophie; Lupia, Enrico; Catanuto, Paola; Periera-Simon, Simone; Xia, Xiaomei; Korach, Ken; Berho, Mariana; Elliot, Sharon J.; Karl, Michael

    2016-01-01

    Podocyte damage and apoptosis are thought to be important if not essential in the development of glomerulosclerosis. Female estrogen receptor knockout mice develop glomerulosclerosis at 9 months of age due to excessive ovarian testosterone production and secretion. Here, we studied the pathogenesis of glomerulosclerosis in this mouse model to determine whether testosterone and/or 17β-estradiol directly affect the function and survival of podocytes. Glomerulosclerosis in these mice was associated with the expression of desmin and the loss of nephrin, markers of podocyte damage and apoptosis. Ovariectomy preserved the function and survival of podocytes by eliminating the source of endogenous testosterone production. In contrast, testosterone supplementation induced podocyte apoptosis in ovariectomized wild-type mice. Importantly, podocytes express functional androgen and estrogen receptors, which, upon stimulation by their respective ligands, have opposing effects. Testosterone induced podocyte apoptosis in vitro by androgen receptor activation, but independent of the TGF-β1 signaling pathway. Pretreatment with 17β-estradiol prevented testosterone-induced podocyte apoptosis, an estrogen receptor-dependent effect mediated by activation of the ERK signaling pathway, and protected podocytes from TGF-β1- or TNF-α-induced apoptosis. Thus, podocytes are target cells for testosterone and 17β-estradiol. These hormones modulate podocyte damage and apoptosis. PMID:20962747

  6. Testosterone and 17β-estradiol have opposite effects on podocyte apoptosis that precedes glomerulosclerosis in female estrogen receptor knockout mice.

    PubMed

    Doublier, Sophie; Lupia, Enrico; Catanuto, Paola; Periera-Simon, Simone; Xia, Xiaomei; Korach, Ken; Berho, Mariana; Elliot, Sharon J; Karl, Michael

    2011-02-01

    Podocyte damage and apoptosis are thought to be important if not essential in the development of glomerulosclerosis. Female estrogen receptor knockout mice develop glomerulosclerosis at 9 months of age due to excessive ovarian testosterone production and secretion. Here, we studied the pathogenesis of glomerulosclerosis in this mouse model to determine whether testosterone and/or 17β-estradiol directly affect the function and survival of podocytes. Glomerulosclerosis in these mice was associated with the expression of desmin and the loss of nephrin, markers of podocyte damage and apoptosis. Ovariectomy preserved the function and survival of podocytes by eliminating the source of endogenous testosterone production. In contrast, testosterone supplementation induced podocyte apoptosis in ovariectomized wild-type mice. Importantly, podocytes express functional androgen and estrogen receptors, which, upon stimulation by their respective ligands, have opposing effects. Testosterone induced podocyte apoptosis in vitro by androgen receptor activation, but independent of the TGF-β1 signaling pathway. Pretreatment with 17β-estradiol prevented testosterone-induced podocyte apoptosis, an estrogen receptor-dependent effect mediated by activation of the ERK signaling pathway, and protected podocytes from TGF-β1- or TNF-α-induced apoptosis. Thus, podocytes are target cells for testosterone and 17β-estradiol. These hormones modulate podocyte damage and apoptosis.

  7. The estrogen receptor alpha nuclear localization sequence is critical for fulvestrant-induced degradation of the receptor.

    PubMed

    Casa, Angelo J; Hochbaum, Daniel; Sreekumar, Sreeja; Oesterreich, Steffi; Lee, Adrian V

    2015-11-05

    Fulvestrant, a selective estrogen receptor down-regulator (SERD) is a pure competitive antagonist of estrogen receptor alpha (ERα). Fulvestrant binds ERα and reduces the receptor's half-life by increasing protein turnover, however, its mechanism of action is not fully understood. In this study, we show that removal of the ERα nuclear localization sequence (ERΔNLS) resulted in a predominantly cytoplasmic ERα that was degraded in response to 17-β-estradiol (E2) but was resistant to degradation by fulvestrant. ERΔNLS bound the ligands and exhibited receptor interaction similar to ERα, indicating that the lack of degradation was not due to disruption of these processes. Forcing ERΔNLS into the nucleus with a heterologous SV40-NLS did not restore degradation, suggesting that the NLS domain itself, and not merely receptor localization, is critical for fulvestrant-induced ERα degradation. Indeed, cloning of the endogenous ERα NLS onto the N-terminus of ERΔNLS significantly restored both its nuclear localization and turnover in response to fulvestrant. Moreover, mutation of the sumoylation targets K266 and K268 within the NLS impaired fulvestrant-induced ERα degradation. In conclusion, our study provides evidence for the unique role of the ERα NLS in fulvestrant-induced degradation of the receptor. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. FDA-Approved Selective Estrogen Receptor Modulators Inhibit Ebola Virus Infection

    PubMed Central

    Johansen, Lisa M.; Brannan, Jennifer M.; Delos, Sue E.; Shoemaker, Charles J.; Stossel, Andrea; Lear, Calli; Hoffstrom, Benjamin G.; DeWald, Lisa Evans; Schornberg, Kathryn L.; Scully, Corinne; Lehár, Joseph; Hensley, Lisa E.; White, Judith M.; Olinger, Gene G.

    2014-01-01

    Ebola viruses remain a substantial threat to both civilian and military populations as bioweapons, during sporadic outbreaks, and from the possibility of accidental importation from endemic regions by infected individuals. Currently, no approved therapeutics exist to treat or prevent infection by Ebola viruses. Therefore, we performed an in vitro screen of Food and Drug Administration (FDA)– and ex–US-approved drugs and selected molecular probes to identify drugs with antiviral activity against the type species Zaire ebolavirus (EBOV). From this screen, we identified a set of selective estrogen receptor modulators (SERMs), including clomiphene and toremifene, which act as potent inhibitors of EBOV infection. Anti-EBOV activity was confirmed for both of these SERMs in an in vivo mouse infection model. This anti-EBOV activity occurred even in the absence of detectable estrogen receptor expression, and both SERMs inhibited virus entry after internalization, suggesting that clomiphene and toremifene are not working through classical pathways associated with the estrogen receptor. Instead, the response appeared to be an off-target effect where the compounds interfere with a step late in viral entry and likely affect the triggering of fusion. These data support the screening of readily available approved drugs to identify therapeutics for the Ebola viruses and other infectious diseases. The SERM compounds described in this report are an immediately actionable class of approved drugs that can be repurposed for treatment of filovirus infections. PMID:23785035

  9. Expression and functional roles of estrogen receptor GPR30 in human intervertebral disc.

    PubMed

    Wei, Aiqun; Shen, Bojiang; Williams, Lisa A; Bhargav, Divya; Yan, Feng; Chong, Beng H; Diwan, Ashish D

    2016-04-01

    Estrogen withdrawal, a characteristic of female aging, is associated with age-related intervertebral disc (IVD) degeneration. The function of estrogen is mediated by two classic nuclear receptors, estrogen receptor (ER)-α and -β, and a membrane bound G-protein-coupled receptor 30 (GPR30). To date, the expression and function of GPR30 in human spine is poorly understood. This study aimed to evaluate GPR30 expression in IVD, and its role in estrogen-related regulation of proliferation and apoptosis of disc nucleus pulposus (NP) cells. GPR30 expression was examined in 30 human adult NP and 9 fetal IVD. Results showed that GPR30 was expressed in NP cells at both mRNA and protein levels. In human fetal IVD, GPR30 protein was expressed in the NP at 12-14 weeks gestation, but was undetectable at 8-11 weeks. The effect of 17β-estradiol (E2) on GPR30-mediated proliferation and interleukin-1β (IL-1β)-induced apoptosis of NP cells was investigated. Cultured NP cells were treated with or without E2, GPR30 antagonist G36, and ER antagonist ICI 182,780. NP cell viability was tested by MTS assay. Apoptosis was determined by flow cytometry using fluorescence labeled annexin-V, TUNEL assay and immumnocytochemical staining of activated caspase-3. E2 enhanced cell proliferation and prevented IL-1β-induced cell death, but the effect was partially blocked by G36 and completely abrogated by a combination of ICI 182,780 and G36. This study demonstrates that GPR30 is expressed in human IVD to transmit signals triggering E2-induced NP cell proliferation and protecting against IL-1β-induced apoptosis. The effects of E2 on NP cells require both GPR30 and classic estrogen receptors. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Estradiol coupling to human monocyte nitric oxide release is dependent on intracellular calcium transients: evidence for an estrogen surface receptor.

    PubMed

    Stefano, G B; Prevot, V; Beauvillain, J C; Fimiani, C; Welters, I; Cadet, P; Breton, C; Pestel, J; Salzet, M; Bilfinger, T V

    1999-10-01

    We tested the hypothesis that estrogen acutely stimulates constitutive NO synthase (cNOS) activity in human peripheral monocytes by acting on an estrogen surface receptor. NO release was measured in real time with an amperometric probe. 17beta-estradiol exposure to monocytes stimulated NO release within seconds in a concentration-dependent manner, whereas 17alpha-estradiol had no effect. 17beta-estradiol conjugated to BSA (E2-BSA) also stimulated NO release, suggesting mediation by a membrane surface receptor. Tamoxifen, an estrogen receptor inhibitor, antagonized the action of both 17beta-estradiol and E2-BSA, whereas ICI 182,780, a selective inhibitor of the nuclear estrogen receptor, had no effect. We further showed, using a dual emission microfluorometry in a calcium-free medium, that the 17beta-estradiol-stimulated release of monocyte NO was dependent on the initial stimulation of intracellular calcium transients in a tamoxifen-sensitive process. Leeching out the intracellular calcium stores abolished the effect of 17beta-estradiol on NO release. RT-PCR analysis of RNA obtained from the cells revealed a strong estrogen receptor-alpha amplification signal and a weak beta signal. Taken together, a physiological dose of estrogen acutely stimulates NO release from human monocytes via the activation of an estrogen surface receptor that is coupled to increases in intracellular calcium.

  11. Estrogen and progesterone receptor testing in breast carcinoma: concordance of results between local and reference laboratories in Brazil.

    PubMed

    Wludarski, Sheila Cristina Lordelo; Lopes, Lisandro Ferreira; Duarte, Ivison Xavier; Carvalho, Filomena Marino; Weiss, Lawrence; Bacchi, Carlos Eduardo

    2011-01-01

    Breast cancer accounts for approximately one quarter of all cancers in females. Estrogen and progesterone receptor testing has become an essential part of the clinical evaluation of breast carcinoma patients, and accurate results are critical in identifying patients who may benefit from hormone therapy. The present study had the aim of investigating the concordance of the results from hormone receptor tests between a reference laboratory and local (or community) laboratories in Brazil. Retrospective study at a reference pathology laboratory. The concordance in the results from hormone receptor tests between a reference laboratory and 146 local laboratories in Brazil was compared in relation to 500 invasive breast carcinoma cases, using immunohistochemistry. There was concordance in 89.4% (447/500 cases) and 85.0% (425/500 cases) of the results from estrogen (κ = 0.744, P < 0.001) and progesterone (κ = 0.688, P < 0.001) receptor tests, respectively, between local and reference laboratories. This was similar to findings in other countries. The false negative rates from estrogen and progesterone receptor tests in local laboratories were 8.7% and 14.4%, respectively. The false positive rates from estrogen and progesterone receptor tests in local laboratories were 15.5% and 16.0%, respectively. Technical and result interpretation issues may explain most of the discordances in hormone receptor testing in local laboratories. Validation of estrogen and progesterone receptor tests at local laboratories, with rigorous quality control measures, is strongly recommended in order to avoid erroneous treatment of breast cancer patients.

  12. T Lymphocytes Do Not Directly Mediate the Protective Effect of Estrogen on Experimental Autoimmune Encephalomyelitis

    PubMed Central

    Polanczyk, Magdalena J.; Jones, Richard E.; Subramanian, Sandhya; Afentoulis, Michael; Rich, Cathleen; Zakroczymski, Melissa; Cooke, Paul; Vandenbark, Arthur A.; Offner, Halina

    2004-01-01

    Gender influences mediated by 17β-estradiol (E2) have been associated with susceptibility to and severity of autoimmune diseases such as diabetes, arthritis, and multiple sclerosis. In this regard, we have shown that estrogen receptor-α (Esr1) is crucial for the protective effect of 17β-estradiol (E2) in murine experimental autoimmune encephalitis (EAE), an animal model of multiple sclerosis. The expression of estrogen receptors among various immune cells (eg, T and B lymphocytes, antigen-presenting cells) suggests that the therapeutic effect of E2 is likely mediated directly through specific receptor binding. However, the target immune cell populations responsive to E2 treatment have not been identified. In the current study, we induced EAE in T-cell-deficient, severe combined immunodeficient mice or in immunocompetent mice with encephalitogenic T cells from wild-type Esr1+/+ or Esr1 knockout (Esr1−/−) donors and compared the protective E2 responses. The results showed that E2-responsive, Esr1+/+ disease-inducing encephalitogenic T cells were neither necessary nor sufficient for E2-mediated protection from EAE. Instead, the therapeutic response appeared to be mediated through direct effects on nonlymphocytic, E2-responsive cells and down-regulation of the inflammatory response in the central nervous system. These results provide the first demonstration that the protective effect of E2 on EAE is not mediated directly through E2-responsive T cells and raise the alternative possibility that nonlymphocytic cells such as macrophages, dendritic cells, or other nonlymphocytic cells are primarily responsive to E2 treatment in EAE. PMID:15579449

  13. Treatment of BG-1 Ovarian Cancer Cells Expressing Estrogen Receptors with Lambda-cyhalothrin and Cypermethrin Caused a Partial Estrogenicity Via an Estrogen Receptor-dependent Pathway

    PubMed Central

    Kim, Cho-Won; Go, Ryeo-Eun

    2015-01-01

    Synthetic pyrethroids (SPs) are the most common pesticides which are recently used for indoor pest control. The widespread use of SPs has resulted in the increased exposure to wild animals and humans. Recently, some SPs are suspected as endocrine disrupting chemicals (EDCs) and have been assessed for their potential estrogenicity by adopting various analyzing assays. In this study, we examined the estrogenic effects of lambda-cyhalothrin (LC) and cypermethrin (CP), the most commonly used pesticides in Korea, using BG-1 ovarian cancer cells expressing estrogen receptors (ERs). To evaluate the estrogenic activities of two SPs, LC and CP, we employed MTT assay and reverse-transcription polymerase chain reaction (RT-PCR) in LC or CP treated BG-1 ovarian cancer cells. In MTT assay, LC (10−6 M) and CP (10−5 M) significantly induced the growth of BG-1 cancer cells. LC or CP-induced cell growth was antagonized by addition of ICI 182,720 (10−8 M), an ER antagonist, suggesting that this effect appears to be mediated by an ER-dependent manner. Moreover, RT-PCR results showed that transcriptional level of cyclin D1, a cell cycle-regulating gene, was significantly up-regulated by LC and CP, while these effects were reversed by co-treatment of ICI 182,780. However, p21, a cyclin D-ckd-4 inhibitor gene, was not altered by LC or CP. Moreover, ERα expression was not significantly changed by LC and CP, while downregulated by E2. Finally, in xenografted mouse model transplanted with human BG-1 ovarian cancer cells, E2 significantly increased the tumor volume compare to a negative control, but LC did not. Taken together, these results suggest that LC and CP may possess estrogenic potentials by stimulating the growth of BG-1 ovarian cancer cells via partially ER signaling pathway associated with cell cycle as did E2, but this estrogenic effect was not found in in vivo mouse model. PMID:26877835

  14. G-protein coupled estrogen receptor 1 expression in rat and human heart: Protective role during ischaemic stress.

    PubMed

    Patel, Vanlata H; Chen, Jing; Ramanjaneya, Manjunath; Karteris, Emmanouil; Zachariades, Elena; Thomas, Peter; Been, Martin; Randeva, Harpal S

    2010-08-01

    G-protein coupled estrogen receptor 1, GPER, formerly known as GPR30, is a seven transmembrane domain receptor that mediates rapid estrogen responses in a wide variety of cell types. To date, little is known about the role of GPER during ischaemia/reperfusion injury. In this study, we report both mRNA and protein expression of GPER in the rat and human heart. The role of GPER in estrogen protection against ischaemic stress in the rat heart was also assessed using the isolated Langendorff system. Pre-treatment with 17beta-estradiol (E2) significantly decreased infarct size, (61.48+/-2.2% to 27.92+/-2.9% (P<0.001). Similarly, treatment with the GPER agonist G1 prior to 30-min global ischaemia followed by 120-min reperfusion significantly reduced infarct size from 61.48+/-2.2% to 23.85+/-3.2% (P<0.001), whilst addition of GPR30 antibody, abolished the protective effect of G1 (infarct size: 55.42+/-1.3%). The results suggest that GPER under cardiac stress exerts direct protection in the heart and may serve as a potential therapeutic target for cardiac drug therapy.

  15. Estrogen receptor accessory proteins augment receptor-DNA interaction and DNA bending.

    PubMed

    Landel, C C; Potthoff, S J; Nardulli, A M; Kushner, P J; Greene, G L

    1997-01-01

    Increasing evidence suggests that accessory proteins play an important role in the ability of the estrogen receptor (ER) and other nuclear hormone receptors to modulate transcription when bound to cis-acting hormone response elements in target genes. We have previously shown that four proteins, hsp70, protein disulfide isomerase (PDI) and two unknown proteins (p48 and p45), copurify with ER that has been isolated by site-specific DNA chromatography (BERE) and influence the interaction of ER with DNA in vitro. To better define the nature of these effects, we used filter binding and electrophoretic mobility shift assays to study the ability of these proteins to alter the kinetics of ER-DNA interaction and to influence the ability of ER to bend DNA when bound to an estrogen response element (ERE). The results of both assays indicate that ERE-purified ER, with its four associated proteins (hsp70, PDI, p48, p45), has a greater ability to bind to the vitellogenin A2 ERE than ER purified by estradiol-Sepharose chromatography in the absence (ESeph) or presence (EATP) of ATP, in which p48, p45 (ESeph) and hsp70 (EATP) are removed. Surprisingly, the rates of association and dissociation of ER and ERE were essentially the same for all three mixtures, suggesting that one or more ER-associated proteins, especially p45 and p48, may be required for ER to attain maximum DNA binding activity. In addition, circular permutation and phasing analyses demonstrated that the same ER-associated proteins produced higher order ER-DNA complexes that significantly increased the magnitude of DNA distortion, but did not alter the direction of the ER-induced bend of ERE-containing DNA fragments, which was toward the major groove of the DNA helix. These results suggest that p45 and/or p48 and possibly hsp70, play an important role both in the specific DNA binding and bending activities of ER and thus contribute to the overall stimulation of transcription in target genes that contain cis

  16. Anti-tumor effect of estrogen-related receptor alpha knockdown on uterine endometrial cancer

    PubMed Central

    Matsushima, Hiroshi; Mori, Taisuke; Ito, Fumitake; Yamamoto, Takuro; Akiyama, Makoto; Kokabu, Tetsuya; Yoriki, Kaori; Umemura, Shiori; Akashi, Kyoko; Kitawaki, Jo

    2016-01-01

    Estrogen-related receptor (ERR)α presents structural similarities with estrogen receptor (ER)α. However, it is an orphan receptor not binding to naturally occurring estrogens. This study was designed to investigate the role of ERRα in endometrial cancer progression. Immunohistochemistry analysis on 50 specimens from patients with endometrial cancer showed that ERRα was expressed in all examined tissues and the elevated expression levels of ERRα were associated with advanced clinical stages and serous histological type (p < 0.01 for each). ERRα knockdown with siRNA suppressed angiogenesis via VEGF and cell proliferation in vitro (p < 0.01). Cell cycle and apoptosis assays using flow cytometry and western blot revealed that ERRα knockdown induced cell cycle arrest during the mitotic phase followed by apoptosis initiated by caspase-3. Additionally, ERRα knockdown sensitized cells to paclitaxel. A significant reduction of tumor growth and angiogenesis was also observed in ERRα knockdown xenografts (p < 0.01). These findings indicate that ERRα may serve as a novel molecular target for the treatment of endometrial cancer. PMID:27153547

  17. Differential Regulation of Native Estrogen Receptor-Regulatory Elements by Estradiol, Tamoxifen, and Raloxifene

    PubMed Central

    Levy, Nitzan; Tatomer, Dierdre; Herber, Candice B.; Zhao, Xiaoyue; Tang, Hui; Sargeant, Toby; Ball, Lonnele J.; Summers, Jonathan; Speed, Terence P.; Leitman, Dale C.

    2008-01-01

    Estrogen receptors (ERs) regulate gene transcription by interacting with regulatory elements. Most information regarding how ER activates genes has come from studies using a small set of target genes or simple consensus sequences such as estrogen response element, activator protein 1, and Sp1 elements. However, these elements cannot explain the differences in gene regulation patterns and clinical effects observed with estradiol (E2) and selective estrogen receptor modulators. To obtain a greater understanding of how E2 and selective estrogen receptor modulators differentially regulate genes, it is necessary to investigate their action on a more comprehensive set of native regulatory elements derived from ER target genes. Here we used chromatin immunoprecipitation-cloning and sequencing to isolate 173 regulatory elements associated with ERα. Most elements were found in the introns (38%) and regions greater than 10 kb upstream of the transcription initiation site (38%); 24% of the elements were found in the proximal promoter region (<10 kb). Only 11% of the elements contained a classical estrogen response element; 23% of the elements did not have any known response elements, including one derived from the naked cuticle homolog gene, which was associated with the recruitment of p160 coactivators. Transfection studies found that 80% of the 173 elements were regulated by E2, raloxifene, or tamoxifen with ERα or ERβ. Tamoxifen was more effective than raloxifene at activating the elements with ERα, whereas raloxifene was superior with ERβ. Our findings demonstrate that E2, tamoxifen, and raloxifene differentially regulate native ER-regulatory elements isolated by chromatin immunoprecipitation with ERα and ERβ. PMID:17962382

  18. Roles of α- and β-estrogen receptors in mouse social recognition memory: effects of gender and the estrous cycle.

    PubMed

    Sánchez-Andrade, G; Kendrick, K M

    2011-01-01

    Establishing clear effects of gender and natural hormonal changes during female ovarian cycles on cognitive function has often proved difficult. Here we have investigated such effects on the formation and long-term (24 h) maintenance of social recognition memory in mice together with the respective involvement of α- and β-estrogen receptors using α- and β-estrogen receptor knockout mice and wildtype controls. Results in wildtype animals showed that while females successfully formed a memory in the context of a habituation/dishabituation paradigm at all stages of their ovarian cycle, only when learning occurred during proestrus (when estrogen levels are highest) was it retained after 24 h. In α-receptor knockout mice (which showed no ovarian cycles) both formation and maintenance of this social recognition memory were impaired, whereas β-receptor knockouts showed no significant deficits and exhibited the same proestrus-dependent retention of memory at 24 h. To investigate possible sex differences, male α- and β-estrogen receptor knockout mice were also tested and showed similar effects to females excepting that α-receptor knockouts had normal memory formation and only exhibited a 24 h retention deficit. This indicates a greater dependence in females on α-receptor expression for memory formation in this task. Since non-specific motivational and attentional aspects of the task were unaffected, our findings suggest a general α-receptor dependent facilitation of memory formation by estrogen as well as an enhanced long-term retention during proestrus. Results are discussed in terms of the differential roles of the two estrogen receptors, the neural substrates involved and putative interactions with oxytocin. Copyright © 2010 Elsevier Inc. All rights reserved.

  19. The Dual Estrogen Receptor α Inhibitory Effects of the Tissue-Selective Estrogen Complex for Endometrial and Breast Safety

    PubMed Central

    Han, Sang Jun; Begum, Khurshida; Foulds, Charles E.; Hamilton, Ross A.; Bailey, Suzanna; Malovannaya, Anna; Chan, Doug; Qin, Jun

    2016-01-01

    The conjugated estrogen/bazedoxifene tissue-selective estrogen complex (TSEC) is designed to minimize the undesirable effects of estrogen in the uterus and breast tissues and to allow the beneficial effects of estrogen in other estrogen-target tissues, such as the bone and brain. However, the molecular mechanism underlying endometrial and breast safety during TSEC use is not fully understood. Estrogen receptor α (ERα)–estrogen response element (ERE)–DNA pull-down assays using HeLa nuclear extracts followed by mass spectrometry–immunoblotting analyses revealed that, upon TSEC treatment, ERα interacted with transcriptional repressors rather than coactivators. Therefore, the TSEC-mediated recruitment of transcriptional repressors suppresses ERα-mediated transcription in the breast and uterus. In addition, TSEC treatment also degraded ERα protein in uterine tissue and breast cancer cells, but not in bone cells. Interestingly, ERα-ERE-DNA pull-down assays also revealed that, upon TSEC treatment, ERα interacted with the F-box protein 45 (FBXO45) E3 ubiquitin ligase. The loss-of- and gain-of-FBXO45 function analyses indicated that FBXO45 is involved in TSEC-mediated degradation of the ERα protein in endometrial and breast cells. In preclinical studies, these synergistic effects of TSEC on ERα inhibition also suppressed the estrogen-dependent progression of endometriosis. Therefore, the endometrial and breast safety effects of TSEC are associated with synergy between the selective recruitment of transcriptional repressors to ERα and FBXO45-mediated degradation of the ERα protein. PMID:26487511

  20. Formononetin promotes angiogenesis through the estrogen receptor alpha-enhanced ROCK pathway

    PubMed Central

    Li, Shang; Dang, Yuanye; Zhou, Xuelin; Huang, Bin; Huang, Xiaohui; Zhang, Zherui; Kwan, Yiu Wa; Chan, Shun Wan; Leung, George Pak Heng; Lee, Simon Ming Yuen; Hoi, Maggie Pui Man

    2015-01-01

    Formononetin is an isoflavone that has been shown to display estrogenic properties and induce angiogenesis activities. However, the interrelationship between the estrogenic properties and angiogenesis activities of formononetin are not well defined. In the present study, docking and enzymatic assay demonstrated that formononetin displayed direct binding to the ligand-binding domain (LBD) of estrogen receptor alpha (ERα) with an agonistic property. Results from Human Umbilical Vein Endothelial Cells (HUVEC) by using real-time migration xCELLigence system, immunofluorescence and western blotting provided strong evidences of formononetin induced endothelial cell migration and dramatic actin cytoskeleton spatial modification through ERα-enhanced-ROCK-II/MMP2/9 signaling pathways. In addition, results from co-immunoprecipitation suggested formononetin induced cell migration via recruiting of ERα/ROCK-II activated complex formation. More interestingly, in zebrafish embryo we observed that formononetin significantly promoted angiogenic sproutings in the subintestinal vessels (SIVs) that could be completely abolished by ROCK inhibitor. In this study, we elucidated the underlying mechanisms that formononetin produced proangiogenesis effects through an ERα-enhanced ROCK-II signaling pathways. Results from the present study also expand our knowledge about the enigmatic underlying mechanisms of phytoestrogenic compounds in the promotion of angiogenesis in relation to ERα and ROCK interaction in endothelial cells and their relationship with actin assembly and cell migration. PMID:26568398

  1. Estrogen Enhances Linkage in the Vascular Endothelial Calmodulin Network via a Feedforward Mechanism at the G Protein-coupled Estrogen Receptor 1*

    PubMed Central

    Tran, Quang-Kim; Firkins, Rachel; Giles, Jennifer; Francis, Sarah; Matnishian, Vahe; Tran, Phuong; VerMeer, Mark; Jasurda, Jake; Burgard, Michelle Ann; Gebert-Oberle, Briana

    2016-01-01

    Estrogen exerts many effects on the vascular endothelium. Calmodulin (CaM) is the transducer of Ca2+ signals and is a limiting factor in cardiovascular tissues. It is unknown whether and how estrogen modifies endothelial functions via the network of CaM-dependent proteins. Here we show that 17β-estradiol (E2) up-regulates total CaM level in endothelial cells. Concurrent measurement of Ca2+ and Ca2+-CaM indicated that E2 also increases free Ca2+-CaM. Pharmacological studies, gene silencing, and receptor expression-specific cell studies indicated that the G protein-coupled estrogen receptor 1 (GPER/GPR30) mediates these effects via transactivation of EGFR and subsequent MAPK activation. The outcomes were then examined on four distinct members of the intracellular CaM target network, including GPER/GPR30 itself and estrogen receptor α, the plasma membrane Ca2+-ATPase (PMCA), and endothelial nitric-oxide synthase (eNOS). E2 substantially increases CaM binding to estrogen receptor α and GPER/GPR30. Mutations that reduced CaM binding to GPER/GPR30 in separate binding domains do not affect GPER/GPR30-Gβγ preassociation but decrease GPER/GPR30-mediated ERK1/2 phosphorylation. E2 increases CaM-PMCA association, but the expected stimulation of Ca2+ efflux is reversed by E2-stimulated tyrosine phosphorylation of PMCA. These effects sustain Ca2+ signals and promote Ca2+-dependent CaM interactions with other CaM targets. Consequently, E2 doubles CaM-eNOS interaction and also promotes dual phosphorylation of eNOS at Ser-617 and Ser-1179. Calculations using in-cell and in vitro data revealed substantial individual and combined contribution of these effects to total eNOS activity. Taken together, E2 generates a feedforward loop via GPER/GPR30, which enhances Ca2+/CaM signals and functional linkage in the endothelial CaM target network. PMID:26987903

  2. Estrogen Enhances Linkage in the Vascular Endothelial Calmodulin Network via a Feedforward Mechanism at the G Protein-coupled Estrogen Receptor 1.

    PubMed

    Tran, Quang-Kim; Firkins, Rachel; Giles, Jennifer; Francis, Sarah; Matnishian, Vahe; Tran, Phuong; VerMeer, Mark; Jasurda, Jake; Burgard, Michelle Ann; Gebert-Oberle, Briana

    2016-05-13

    Estrogen exerts many effects on the vascular endothelium. Calmodulin (CaM) is the transducer of Ca(2+) signals and is a limiting factor in cardiovascular tissues. It is unknown whether and how estrogen modifies endothelial functions via the network of CaM-dependent proteins. Here we show that 17β-estradiol (E2) up-regulates total CaM level in endothelial cells. Concurrent measurement of Ca(2+) and Ca(2+)-CaM indicated that E2 also increases free Ca(2+)-CaM. Pharmacological studies, gene silencing, and receptor expression-specific cell studies indicated that the G protein-coupled estrogen receptor 1 (GPER/GPR30) mediates these effects via transactivation of EGFR and subsequent MAPK activation. The outcomes were then examined on four distinct members of the intracellular CaM target network, including GPER/GPR30 itself and estrogen receptor α, the plasma membrane Ca(2+)-ATPase (PMCA), and endothelial nitric-oxide synthase (eNOS). E2 substantially increases CaM binding to estrogen receptor α and GPER/GPR30. Mutations that reduced CaM binding to GPER/GPR30 in separate binding domains do not affect GPER/GPR30-Gβγ preassociation but decrease GPER/GPR30-mediated ERK1/2 phosphorylation. E2 increases CaM-PMCA association, but the expected stimulation of Ca(2+) efflux is reversed by E2-stimulated tyrosine phosphorylation of PMCA. These effects sustain Ca(2+) signals and promote Ca(2+)-dependent CaM interactions with other CaM targets. Consequently, E2 doubles CaM-eNOS interaction and also promotes dual phosphorylation of eNOS at Ser-617 and Ser-1179. Calculations using in-cell and in vitro data revealed substantial individual and combined contribution of these effects to total eNOS activity. Taken together, E2 generates a feedforward loop via GPER/GPR30, which enhances Ca(2+)/CaM signals and functional linkage in the endothelial CaM target network. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Estrogen, Angiogenesis, Immunity and Cell Metabolism: Solving the Puzzle.

    PubMed

    Trenti, Annalisa; Tedesco, Serena; Boscaro, Carlotta; Trevisi, Lucia; Bolego, Chiara; Cignarella, Andrea

    2018-03-15

    Estrogen plays an important role in the regulation of cardiovascular physiology and the immune system by inducing direct effects on multiple cell types including immune and vascular cells. Sex steroid hormones are implicated in cardiovascular protection, including endothelial healing in case of arterial injury and collateral vessel formation in ischemic tissue. Estrogen can exert potent modulation effects at all levels of the innate and adaptive immune systems. Their action is mediated by interaction with classical estrogen receptors (ERs), ERα and ERβ, as well as the more recently identified G-protein coupled receptor 30/G-protein estrogen receptor 1 (GPER1), via both genomic and non-genomic mechanisms. Emerging data from the literature suggest that estrogen deficiency in menopause is associated with an increased potential for an unresolved inflammatory status. In this review, we provide an overview through the puzzle pieces of how 17β-estradiol can influence the cardiovascular and immune systems.

  4. Bisphenol A (BPA) binding on full-length architectures of estrogen receptor.

    PubMed

    Liu, Yaquan; Qu, Kaili; Hai, Ying; Zhao, Chunyan

    2018-08-01

    Previous research has shown that the major toxicity mechanism for many environment chemicals is binding with estrogen receptor (ER) and blocking endogenous estrogen access, including bisphenol A (BPA). However, the molecular level understanding the global consequence of BPA binding on the full-length architectures of ER is largely unknown, which is a necessary stage to evaluate estrogen-like toxicity of BPA. In the present work, the consequence of BPA on full-length architectures of ER was firstly modeled based on molecular dynamics, focusing on the cross communication between multi-domains including ligand binding domain (LBD) and DNA binding domain (DBD). The study proved consequence of BPA upon full-length ER structure was dependent on long-range communications between multiple protein domains. The allosteric effects occurring in LBD units could alter dimerization formation through a crucial change in residue-residue connections, which resulted in relaxation of DBD. It indicated BPA could present consequence on the full-size receptor, not only on the separate domains, but also on the cross communication among LBD, DBD, and DNA molecules. It might provide detailed insight into the knowledge about the structural characteristics of ER and its role in gene regulation, which eventually helped us evaluate the estrogen-like toxicity upon BPA binding with full-length ER. © 2018 Wiley Periodicals, Inc.

  5. Androgenic/estrogenic balance in the male rat cerebral circulation: metabolic enzymes and sex steroid receptors

    PubMed Central

    Gonzales, Rayna J; Ansar, Saema; Duckles, Sue P; Krause, Diana N

    2008-01-01

    Tissues from males can be regulated by a balance of androgenic and estrogenic effects because of local metabolism of testosterone and expression of relevant steroid hormone receptors. As a critical first step to understanding sex hormone influences in the cerebral circulation of males, we investigated the presence of enzymes that metabolize testosterone to active products and their respective receptors. We found that cerebral blood vessels from male rats express 5α-reductase type 2 and aromatase, enzymes responsible for conversion of testosterone into dihydrotestosterone (DHT) and 17β-estradiol, respectively. Protein levels of these enzymes, however, were not modulated by long-term in vivo hormone treatment. We also showed the presence of receptors for both androgens (AR) and estrogens (ER) from male cerebral vessels. Western blot analysis showed bands corresponding to the full-length AR (110 kDa) and ERα (66 kDa). Long-term in vivo treatment of orchiectomized rats with testosterone or DHT, but not estrogen, increased AR levels in cerebral vessels. In contrast, ERα protein levels were increased after in vivo treatment with estrogen but not testosterone. Fluorescent immunostaining revealed ERα, AR, and 5α-reductase type 2 in both the endothelial and smooth muscle layers of cerebral arteries, whereas aromatase staining was solely localized to the endothelium. Thus, cerebral vessels from males are target tissues for both androgens and estrogen. Furthermore, local metabolism of testosterone might balance opposing androgenic and estrogenic influences on cerebrovascular as well as brain function in males. PMID:17406656

  6. Characterization of an estrogen-responsive element implicated in regulation of the rainbow trout estrogen receptor gene.

    PubMed

    Le Dréan, Y; Lazennec, G; Kern, L; Saligaut, D; Pakdel, F; Valotaire, Y

    1995-08-01

    We previously reported that the expression of the rainbow trout estrogen receptor (rtER) gene is markedly increased by estradiol (E2). In this paper, we have used transient transfection assays with reporter plasmids expressing chloramphenicol acetyl transferase (CAT), linked to 5' flanking regions of the rtER gene promoter, to identify cis-elements responsible for E2 inducibility. Deletion analysis localized an estrogen-responsive element (ERE), at position +242, with one mutation on the first base compared with the consensus sequence. This element confers estrogen responsiveness to CAT reporter linked to both the herpes simplex virus thymidine kinase promoter and the homologous rtER promoter. Moreover, using a 0.2 kb fragment of the rtER promoter encompassing the ERE and the rtER DNA binding domain obtained from a bacterial expression system, DNase I footprinting experiments demonstrated a specific protection covering 20 bp (+240/+260) containing the ERE sequence. Based on these studies, we believe that this ERE sequence, identified in the rtER gene promoter, may be a major cis-acting element involved in the regulation of the gene by estrogen.

  7. Lupinalbin A as the most potent estrogen receptor α- and aryl hydrocarbon receptor agonist in Eriosema laurentii de Wild. (Leguminosae).

    PubMed

    Ateba, Sylvin Benjamin; Njamen, Dieudonné; Medjakovic, Svjetlana; Zehl, Martin; Kaehlig, Hanspeter; Jungbauer, Alois; Krenn, Liselotte

    2014-08-09

    Eriosema laurentii De Wild. (Leguminosae) is a plant used in Cameroon against infertility and gynecological or menopausal complaints. In our previous report, a methanol extract of its aerial parts was shown to exhibit estrogenic and aryl hydrocarbon receptor agonistic activities in vitro and to prevent menopausal symptoms in ovariectomized Wistar rats. In order to determine the major estrogen receptor α (ERα) agonists in the extract, an activity-guided fractionation was performed using the ERα yeast screen. To check whether the ERα active fractions/compounds also accounted for the aryl hydrocarbon receptor (AhR) agonistic activity of the crude methanol extract, they were further tested on the AhR yeast screen. This study led to the identification of 2'-hydroxygenistein, lupinalbin A and genistein as major estrogenic principles of the extract. 2'-hydroxygenistein and lupinalbin A were, for the first time, also shown to possess an AhR agonistic activity, whereas genistein was not active in this assay. In addition, it was possible to deduce structure-activity relationships. These results suggest that the identified compounds are the major active principles responsible for the estrogenic and AhR agonistic activities of the crude methanol extract of the aerial parts of Eriosema laurentii.

  8. Expression of estrogen receptors-alpha and -beta in the pregnant ovine uterine artery endothelial cells in vivo and in vitro.

    PubMed

    Liao, Wu Xiang; Magness, Ronald R; Chen, Dong-Bao

    2005-03-01

    Estrogen is recognized to be one of the driving forces in increases in uterine blood flow through both rapid and delayed actions via binding to its receptors, ER alpha and ER beta at the uterine artery (UA) wall, and especially in UA endothelium (UAE). However, information regarding estrogen receptor (ER) expression in UAE is limited. This study was designed to test whether ERs are expressed in UAE in vivo, and if they are, whether these receptors are maintained in cultured UA endothelial cells (UAECs) in vitro. By using immunohistochemical and Western blot analyses, we clearly demonstrated ER alpha and ER beta protein expression in pregnant (Days 120-130) sheep UA and UAE in vivo and as well as cultured UAECs in vitro. Reverse transcription-polymerase chain reaction (RT-PCR) amplified both ER alpha and ER beta mRNAs in UA, UAE, and UAECs. Of interest, a truncated ER beta (ER beta2) variant due to a splicing deletion of exon 5 of the ER beta gene was detected in these cells. Quantitative RT-PCR analysis revealed that ER alpha mRNA levels are approximately 8-fold (P < 0.01) higher than that of ER beta in UAECs, indicating that ER alpha may play a more important role than ER beta in the UAEC responses to estrogen. Fluorescence immunolabeling analysis showed that ER alpha is present in both nuclei and plasma membranes in UAECs, and the latter is also colocalized with caveolin-1. The membrane and nuclear ER alpha presumably participate in rapid and delayed responses, respectively, to estrogen on UAE. Taken together, our data demonstrated that UAE is a direct target of estrogen actions and that the UAEC culture model we established is suitable for dissecting estrogen actions on UAE.

  9. Sex and seasonal differences in mRNA expression of estrogen receptor α (ESR1) in red-sided garter snakes (Thamnophis sirtalis parietalis).

    PubMed

    Ashton, Sydney E; Vernasco, Ben J; Moore, Ignacio T; Parker, M Rockwell

    2018-05-25

    Estrogens are important regulators of reproductive physiology including sexual signal expression and vitellogenesis. For the regulation to occur, the hormone must bind and activate receptors in target tissues, and expression of the receptors can vary by sex and/or season. By simultaneously comparing circulating hormone levels with receptor expression, a more complete understanding of hormone action can be gained. Our study species, the red-sided garter snake (Thamnophis sirtalis parietalis), provides an excellent opportunity to study the interaction between sex steroid hormones and receptor expression in addition to sexual dimorphism and seasonality. During the spring mating season, male garter snakes rely exclusively on the female's skin-based, estrogen-dependent sex pheromone to direct courtship. Males can be stimulated to produce this sexual attractiveness pheromone by treatment with estradiol (E 2 ), which also induces male vitellogenesis. Estrogen receptors (ESRs) are required to transduce the effects of estrogens, thus we used quantitative RT-PCR to analyze expression of ESR alpha (ERα; gene ESR1) mRNA in the skin and liver of wild caught male and female garter snakes across simulated spring and fall conditions in the laboratory. While ESR1 was present in the skin of both sexes, there were no sex or seasonal differences in expression levels. Liver expression of ESR1, however, was sexually dimorphic, with females showing greatest expression in fall when circulating E 2 concentrations were lowest. There were no statistically significant correlations between E 2 and ESR1 expression. Our data suggest that the skin of both sexes is sensitive to estrogen signaling and thus the production of sex pheromone is dependent on bioavailable levels of E 2 . Female expression of ESR1 in the liver may increase in the fall to prime energy storage mechanisms required for vitellogenesis the following year. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Determination of the Role of Estrogen Receptors and Estrogen Regulated Genes in B Cell Autoreactivity

    DTIC Science & Technology

    2011-07-01

    Betty Diamond – DOD FINAL REPORT 9 Figure 3: (A) expression of estrogen receptors ERalpha( Esr1 ) and ERbeta (Esr2) in splenic B cells and (B...Urinary 16 OH-Estradiol metabolite in BALB/c and C57BL6 mice. Esr1 0 0.05 0.1 0.15 0.2 Transit. Mature Transit. Mature Transit. Mature Transit. mature P E2

  11. Regulation of the intronic promoter of rat estrogen receptor alpha gene, responsible for truncated estrogen receptor product-1 expression.

    PubMed

    Schausi, Diane; Tiffoche, Christophe; Thieulant, Marie-Lise

    2003-07-01

    We have characterized the intronic promoter of the rat estrogen receptor (ER) alpha gene, responsible for the lactotrope-specific truncated ER product (TERP)-1 isoform expression. Transcriptional regulation was investigated by transient transfections using 5'-deletion constructs. TERP promoter constructs were highly active in MMQ cells, a pure lactotrope cell line, whereas a low basal activity was detected in alphaT3-1 gonadotrope cells or in COS-7 monkey kidney cells. Serial deletion analysis revealed that 1) a minimal -693-bp region encompassing the TATA box is sufficient to allow lactotrope-specific expression; 2) the promoter contains strong positive cis-acting elements both in the distal and proximal regions, and 3) the region spanning the -1698/-1194 region includes repressor elements. Transient transfection studies, EMSAs, and gel shifts demonstrated that estrogen activates the TERP promoter via an estrogen-responsive element (ERE1) located within the proximal region. Mutation of ERE1 site completely abolishes the estradiol-dependent transcription, indicating that ERE1 site is sufficient to confer estrogen responsiveness to TERP promoter. In addition, ERalpha action was synergized by transfection of the pituitary-specific factor Pit-1. EMSAs showed that a single Pit-1 DNA binding element in the vicinity of the TATA box is sufficient to confer response by the TERP promoter. In conclusion, we demonstrated, for the first time, that TERP promoter regulation involves ERE and Pit-1 cis-elements and corresponding trans-acting factors, which could play a role in the physiological changes that occur in TERP-1 transcription in lactotrope cells.

  12. The polymorphism of estrogen receptor α is important for metabolic consequences associated with menopause.

    PubMed

    Pinkas, Jarosław; Gujski, Mariusz; Wierzbińska-Stępniak, Anna; Owoc, Alfred; Bojar, Iwona

    2016-01-01

    Menopause is associated with multiple health and metabolic consequences resulting from the decrease in estrogens level. Women at postmenopausal age are burdened with a higher risk of cardiovascular diseases, and the main cause of mortality in this group is ischemic heart disease. Estrogen deficiency is related, among other things, with frequent occurrence of dislipidemia, cessation of the beneficial effect of estrogens on the vascular wall, increase in body weight characterized by unfavourable redistribution of fatty tissue, with an increased amount of visceral fat and reduction of so-called non-fatty body mass. Estrogens exert an effect on metabolism, mainly through the genomic mechanism. The presence of α and β estrogen receptors was found in many tissues and organs. Recently, attention was paid to the fact that the effect of estrogens action on tissues and organs may depend not only on distribution, but also on their polymorphic types. The article presents the latest approach to the problem of metabolic consequences resulting from menopause, according to the possessed α estrogen receptor polymorphism (ERα).Genes encoding for ERα have many polymorphic variants, the most important of which from the clinical aspect are two single nucleotide polymorphisms (SNPs) - Xba1 and PvuII. The review of literature indicates that ERα polymorphisms are of great importance with respect to the effect of estrogens on the functioning of the body of a woman after menopause, and may imply the development of many pathological states, including the prevention or development of metabolic disorders. Identifying ERα polymorphisms may be useful in case of estrogen therapy for menopausal women who may benefit from it.

  13. Mixture Effects of Estrogenic Pesticides at the Human Estrogen Receptor α and β

    PubMed Central

    Seeger, Bettina; Klawonn, Frank; Nguema Bekale, Boris; Steinberg, Pablo

    2016-01-01

    Consumers of fruits and vegetables are frequently exposed to small amounts of hormonally active pesticides, some of them sharing a common mode of action such as the activation of the human estrogen receptor α (hERα) or β (hERβ). Therefore, it is of particular importance to evaluate risks emanating from chemical mixtures, in which the individual pesticides are present at human-relevant concentrations, below their corresponding maximum residue levels. Binary and ternary iso-effective mixtures of estrogenic pesticides at effect concentrations eliciting a 1 or 10% effect in the presence or absence of 17β-estradiol were tested experimentally at the hERα in the yeast-based estrogen screen (YES) assay as well as in the human U2-OS cell-based ERα chemical-activated luciferase gene expression (ERα CALUX) assay and at the hERβ in the ERβ CALUX assay. The outcome was then compared to predictions calculated by means of concentration addition. In most cases, additive effects were observed with the tested combinations in all three test systems, an observation that supports the need to expand the risk assessment of pesticides and consider cumulative risk assessment. An additional testing of mixture effects at the hERβ showed that most test substances being active at the hERα could also elicit additive effects at the hERβ, but the hERβ was less sensitive. In conclusion, effects of the same ligands at the hERα and the hERβ could influence the estrogenic outcome under physiological conditions. PMID:26812056

  14. Estrogen-Related Receptors and the control of bone cell fate.

    PubMed

    Carnesecchi, Julie; Vanacker, Jean-Marc

    2016-09-05

    Bone loss is naturally occurring in aging males and females and exacerbated in the latter after menopause, altogether leading to cumulative skeleton fragility and increased fracture risk. Two types of therapeutic strategies can be envisioned to counteract age- or menopause-associated bone loss, aiming at either reducing bone resorption exerted by osteoclasts or, alternatively, promoting bone formation by osteoblasts. We here summarize data suggesting that inhibition of the Estrogen-Related Receptors α and/or γ could promote bone formation and compensate for bone loss induced by ageing or estrogen-deficiency. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Role of dietary bioactive natural products in estrogen receptor-positive breast cancer

    PubMed Central

    Bak, Min Ji; Das Gupta, Soumyasri; Wahler, Joseph; Suh, Nanjoo

    2016-01-01

    Estrogen receptor (ER)-positive breast cancer, including luminal-A and -B, is the most common type of breast cancer. Extended exposure to estrogen is associated with an increased risk of breast cancer. Both ER-dependent and ER-independent mechanisms have been implicated in estrogen-mediated carcinogenesis. The ER-dependent pathway involves cell growth and proliferation triggered by the binding of estrogen to the ER. The ER-independent mechanisms depend on the metabolism of estrogen to generate genotoxic metabolites, free radicals and reactive oxygen species to induce breast cancer. A better understanding of the mechanisms that drive ER-positive breast cancer will help optimize targeted approaches to prevent or treat breast cancer. A growing emphasis is being placed on alternative medicine and dietary approaches toward the prevention and treatment of breast cancer. Many natural products and bioactive compounds found in foods have been shown to inhibit breast carcinogenesis via inhibition of estrogen induced oxidative stress as well as ER signaling. This review summarizes the role of bioactive natural products that are involved in the prevention and treatment of estrogen-related and ER-positive breast cancer. PMID:27016037

  16. Epithelial estrogen receptor 1 intrinsically mediates squamous differentiation in the mouse vagina.

    PubMed

    Miyagawa, Shinichi; Iguchi, Taisen

    2015-10-20

    Estrogen-mediated actions in female reproductive organs are tightly regulated, mainly through estrogen receptor 1 (ESR1). The mouse vaginal epithelium cyclically exhibits cell proliferation and differentiation in response to estrogen and provides a unique model for analyzing the homeostasis of stratified squamous epithelia. To address the role of ESR1-mediated tissue events during homeostasis, we analyzed mice with a vaginal epithelium-specific knockout of Esr1 driven by keratin 5-Cre (K5-Esr1KO). We show here that loss of epithelial ESR1 in the vagina resulted in aberrant epithelial cell proliferation in the suprabasal cell layers and led to failure of keratinized differentiation. Gene expression analysis showed that several known estrogen target genes, including erbB growth factor ligands, were not induced by estrogen in the K5-Esr1KO mouse vagina. Organ culture experiments revealed that the addition of erbB growth factor ligands, such as amphiregulin, could activate keratinized differentiation in the absence of epithelial ESR1. Thus, epithelial ESR1 integrates estrogen and growth factor signaling to mediate regulation of cell proliferation in squamous differentiation, and our results provide new insights into estrogen-mediated homeostasis in female reproductive organs.

  17. Roles of G protein-coupled estrogen receptor GPER in metabolic regulation.

    PubMed

    Sharma, Geetanjali; Mauvais-Jarvis, Franck; Prossnitz, Eric R

    2018-02-01

    Metabolic homeostasis is differentially regulated in males and females. The lower incidence of obesity and associated diseases in pre-menopausal females points towards the beneficial role of the predominant estrogen, 17β-estradiol (E2). The actions of E2 are elicited by nuclear and extra-nuclear estrogen receptor (ER) α and ERβ, as well as the G protein-coupled estrogen receptor (GPER, previously termed GPR30). The roles of GPER in the regulation of metabolism are only beginning to emerge and much remains unclear. The present review highlights recent advances implicating the importance of GPER in metabolic regulation. Assessment of the specific metabolic roles of GPER employing GPER-deficient mice and highly selective GPER-targeted pharmacological agents, agonist G-1 and antagonists G-15 and G36, is also presented. Evidence from in vitro and in vivo studies involving either GPER deficiency or selective activation suggests that GPER is involved in body weight regulation, glucose and lipid homeostasis as well as inflammation. The therapeutic potential of activating GPER signaling through selective ligands for the treatment of obesity and diabetes is also discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. The Estrogen Receptor and Its Variants as Risk Factors in Breast Cancer

    DTIC Science & Technology

    2000-11-01

    34Materials and Methods." observation that the ratio of SRA:AIB I is also significantly increased PCR products were separated on 6% acrylamide gels. which...prostate cancer Gerry Coetzee: Androgen receptor CAG repeat length and breast and prostate cancer risk 1030 COFFEE 1100 Session 2 - Receptor structure...Parker: Role of p160 coactivators in transcriptional activation by estrogen receptors and cross-coupling to other signalling pathways 1550 COFFEE 1615

  19. Type-I Insulin-Like Growth Factor Receptor (IGF1R)-Estrogen Receptor (ER) Crosstalk Contributes to Antiestrogen Therapy Resistance in Breast Cancer Cells

    DTIC Science & Technology

    2013-02-01

    penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR...great success in treating estrogen receptor (ER) positive breast cancer. However, both acquired and de novo resistance to this therapy prevents it from...has shown great success in treating estrogen receptor (ER) positive breast tumors. However, both acquired and de novo resistance to this therapy

  20. Biosensors Paving the Way to Understanding the Interaction between Cadmium and the Estrogen Receptor Alpha

    PubMed Central

    Fechner, Peter; Damdimopoulou, Pauliina; Gauglitz, Günter

    2011-01-01

    Cadmium is a toxic heavy metal ubiquitously present in the environment and subsequently in the human diet. Cadmium has been proposed to disrupt the endocrine system, targeting in particular the estrogen signaling pathway already at environmentally relevant concentrations. Thus far, the reports on the binding affinity of cadmium towards human estrogen receptor alpha (hERα) have been contradicting, as have been the reports on the in vivo estrogenicity of cadmium. Hence, the mode of interaction between cadmium and the receptor remains unclear. Here, we investigated the interaction between cadmium and hERα on a molecular level by applying a novel, label-free biosensor technique based on reflectometric interference spectroscopy (RIfS). We studied the binding of cadmium to hERα, and the conformation of the receptor following cadmium treatment. Our data reveals that cadmium interacts with the ligand binding domain (LBD) of the ERα and affects the conformation of the receptor. However, the binding event, as well as the induced conformation change, greatly depends on the accessibility of the cysteine tails in the LBD. As the LBD cysteine residues have been reported as targets of post-translational modifications in vivo, we present a hypothesis according to which different cellular pools of ERα respond to cadmium differently. Our proposed theory could help to explain some of the previously contradicting results regarding estrogen-like activity of cadmium. PMID:21829690

  1. Post-synaptic Density-95 (PSD-95) Binding Capacity of G-protein-coupled Receptor 30 (GPR30), an Estrogen Receptor That Can Be Identified in Hippocampal Dendritic Spines*

    PubMed Central

    Akama, Keith T.; Thompson, Louisa I.; Milner, Teresa A.; McEwen, Bruce S.

    2013-01-01

    The estrogen 17β-estradiol (E2) modulates dendritic spine plasticity in the cornu ammonis 1 (CA1) region of the hippocampus, and GPR30 (G-protein coupled estrogen receptor 1 (GPER1)) is an estrogen-sensitive G-protein-coupled receptor (GPCR) that is expressed in the mammalian brain and in specific subregions that are responsive to E2, including the hippocampus. The subcellular localization of hippocampal GPR30, however, remains unclear. Here, we demonstrate that GPR30 immunoreactivity is detected in dendritic spines of rat CA1 hippocampal neurons in vivo and that GPR30 protein can be found in rat brain synaptosomes. GPR30 immunoreactivity is identified at the post-synaptic density (PSD) and in the adjacent peri-synaptic zone, and GPR30 can associate with the spine scaffolding protein PSD-95 both in vitro and in vivo. This PSD-95 binding capacity of GPR30 is specific and determined by the receptor C-terminal tail that is both necessary and sufficient for PSD-95 interaction. The interaction with PSD-95 functions to increase GPR30 protein levels residing at the plasma membrane surface. GPR30 associates with the N-terminal tandem pair of PDZ domains in PSD-95, suggesting that PSD-95 may be involved in clustering GPR30 with other receptors in the hippocampus. We demonstrate that GPR30 has the potential to associate with additional post-synaptic GPCRs, including the membrane progestin receptor, the corticotropin releasing hormone receptor, and the 5HT1a serotonin receptor. These data demonstrate that GPR30 is well positioned in the dendritic spine compartment to integrate E2 sensitivity directly onto multiple inputs on synaptic activity and might begin to provide a molecular explanation as to how E2 modulates dendritic spine plasticity. PMID:23300088

  2. Post-synaptic density-95 (PSD-95) binding capacity of G-protein-coupled receptor 30 (GPR30), an estrogen receptor that can be identified in hippocampal dendritic spines.

    PubMed

    Akama, Keith T; Thompson, Louisa I; Milner, Teresa A; McEwen, Bruce S

    2013-03-01

    The estrogen 17β-estradiol (E2) modulates dendritic spine plasticity in the cornu ammonis 1 (CA1) region of the hippocampus, and GPR30 (G-protein coupled estrogen receptor 1 (GPER1)) is an estrogen-sensitive G-protein-coupled receptor (GPCR) that is expressed in the mammalian brain and in specific subregions that are responsive to E2, including the hippocampus. The subcellular localization of hippocampal GPR30, however, remains unclear. Here, we demonstrate that GPR30 immunoreactivity is detected in dendritic spines of rat CA1 hippocampal neurons in vivo and that GPR30 protein can be found in rat brain synaptosomes. GPR30 immunoreactivity is identified at the post-synaptic density (PSD) and in the adjacent peri-synaptic zone, and GPR30 can associate with the spine scaffolding protein PSD-95 both in vitro and in vivo. This PSD-95 binding capacity of GPR30 is specific and determined by the receptor C-terminal tail that is both necessary and sufficient for PSD-95 interaction. The interaction with PSD-95 functions to increase GPR30 protein levels residing at the plasma membrane surface. GPR30 associates with the N-terminal tandem pair of PDZ domains in PSD-95, suggesting that PSD-95 may be involved in clustering GPR30 with other receptors in the hippocampus. We demonstrate that GPR30 has the potential to associate with additional post-synaptic GPCRs, including the membrane progestin receptor, the corticotropin releasing hormone receptor, and the 5HT1a serotonin receptor. These data demonstrate that GPR30 is well positioned in the dendritic spine compartment to integrate E2 sensitivity directly onto multiple inputs on synaptic activity and might begin to provide a molecular explanation as to how E2 modulates dendritic spine plasticity.

  3. Expression pattern of G protein‑coupled estrogen receptor 1 (GPER) in human cumulus granulosa cells (CGCs) of patients with PCOS.

    PubMed

    Zang, Lili; Zhang, Quan; Zhou, Yi; Zhao, Yan; Lu, Linlin; Jiang, Zhou; Peng, Zhen; Zou, Shuhua

    2016-06-01

    Estradiol mediates its actions by binding to classical nuclear receptors, estrogen receptor α (ER-α) and estrogen receptor β (ER-β), and the non-classical G protein-coupled estrogen receptor 1(GPER). Several gene knockdown models have shown the importance of the receptors for growth of the oocyte and for ovulation. The aim of our study was to identify the pattern of GPER expression in human cumulus granulosa cells (CGCs) from ovarian follicles at different stages of oocyte maturation, and the differences of GPER expression between polycystic ovary syndrome (PCOS) patients and non-PCOS women. Thirty-eight cases of PCOS patients and a control group of thirty-two infertile women without PCOS were used in this study. GPER's location in CGCs was investigated by immunohistochemistry. Quantitative RT-PCR and western blot were used to identify the quantify GPER expression. Here we demonstrated that GPER was expressed in CGCs of both PCOS patients and non-PCOS women, and the expression of GPER was decreased significantly during oocyte maturation. But the expression levels of GPER in CGCs of PCOS patients and non-PCOS women were not significantly different. The data indicate that GPER may play a role during human oocyte maturation through its action in cumulus granulosa cells. AMHRIIs: anti-Mullerian hormone type II receptors; BMI: body mass index; CGCs: cumulus granulosa cells; COH: controlled ovarian hyperstimulation; E2: estradiol; EGFR: epidermal growth factor receptor; ER-α: estrogen receptor; ER-β: estrogen receptor β; FF: follicular fluid; FSH: follicle-stimulating hormone; GCs: granulosa cells; GPER: G protein-coupled estrogen receptor 1; GV: germinal vesicle; GVBD: germinal vesicle breakdown; HCG: human chorionic gonadotropin; IRS: immunoreactive score; IVF-ET: in vitro fertilization and embryo transfer; MI: metaphase I; MII: metaphase II; MAPK: mitogen-activated protein kinase; OCCCs: oocyte corona cumulus complexes; PCOS: polycystic ovarian syndrome; q

  4. Liganded and unliganded activation of estrogen receptor and hormone replacement therapies.

    PubMed

    Maggi, Adriana

    2011-08-01

    Over the past two decades, our understanding of estrogen receptor physiology in mammals widened considerably as we acquired a deeper appreciation of the roles of estrogen receptor alpha and beta (ERα and ERβ) in reproduction as well as in bone and metabolic homeostasis, depression, vascular disorders, neurodegenerative diseases and cancer. In addition, our insights on ER transcriptional functions in cells increased considerably with the demonstration that ER activity is not strictly dependent on ligand availability. Indeed, unliganded ERs may be transcriptionally active and post-translational modifications play a major role in this context. The finding that several intracellular transduction molecules may regulate ER transcriptional programs indicates that ERs may act as a hub where several molecular pathways converge: this allows to maintain ER transcriptional activity in tune with all cell functions. Likely, the biological relevant role of ER was favored by evolution as a mean of integration between reproductive and metabolic functions. We here review the post-translational modifications modulating ER transcriptional activity in the presence or in the absence of estrogens and underline their potential role for ER tissue-specific activities. In our opinion, a better comprehension of the variety of molecular events that control ER activity in reproductive and non-reproductive organs is the foundation for the design of safer and more efficacious hormone-based therapies, particularly for menopause. This article is part of a Special Issue entitled: Translating Nuclear receptors from health to disease. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Melatonin decreases estrogen receptor binding to estrogen response elements sites on the OCT4 gene in human breast cancer stem cells

    PubMed Central

    Lopes, Juliana; Arnosti, David; Trosko, James E.; Tai, Mei-Hui; Zuccari, Debora

    2016-01-01

    Cancer stem cells (CSCs) pose a challenge in cancer treatment, as these cells can drive tumor growth and are resistant to chemotherapy. Melatonin exerts its oncostatic effects through the estrogen receptor (ER) pathway in cancer cells, however its action in CSCs is unclear. Here, we evaluated the effect of melatonin on the regulation of the transcription factor OCT4 (Octamer Binding 4) by estrogen receptor alpha (ERα) in breast cancer stem cells (BCSCs). The cells were grown as a cell suspension or as anchorage independent growth, for the mammospheres growth, representing the CSCs population and treated with 10 nM estrogen (E2) or 10 μM of the environmental estrogen Bisphenol A (BPA) and 1 mM of melatonin. At the end, the cell growth as well as OCT4 and ERα expression and the binding activity of ERα to the OCT4 was assessed. The increase in number and size of mammospheres induced by E2 or BPA was reduced by melatonin treatment. Furthermore, binding of the ERα to OCT4 was reduced, accompanied by a reduction of OCT4 and ERα expression. Thus, melatonin treatment is effective against proliferation of BCSCs in vitro and impacts the ER pathway, demonstrating its potential therapeutic use in breast cancer. PMID:27551335

  6. Stimulating the GPR30 estrogen receptor with a novel tamoxifen analogue activates SF-1 and promotes endometrial cell proliferation.

    PubMed

    Lin, Benjamin C; Suzawa, Miyuki; Blind, Raymond D; Tobias, Sandra C; Bulun, Serdar E; Scanlan, Thomas S; Ingraham, Holly A

    2009-07-01

    Estrogens and selective estrogen receptor (ER) modulators such as tamoxifen are known to increase uterine cell proliferation. Mounting evidence suggests that estrogen signaling is mediated not only by ERalpha and ERbeta nuclear receptors, but also by GPR30 (GPER), a seven transmembrane (7TM) receptor. Here, we report that primary human endometriotic H-38 cells express high levels of GPR30 with no detectable ERalpha or ERbeta. Using a novel tamoxifen analogue, STX, which activates GPR30 but not ERs, significant stimulation of the phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways was observed in H-38 cells and in Ishikawa endometrial cancer cells expressing GPR30; a similar effect was observed in JEG3 choriocarcinoma cells. STX treatment also increased cellular pools of phosphatidylinositol (3,4,5) triphosphate, a proposed ligand for the nuclear hormone receptor SF-1 (NR5A1). Consistent with these findings, STX, tamoxifen, and the phytoestrogen genistein were able to increase SF-1 transcription, promote Ishikawa cell proliferation, and induce the SF-1 target gene aromatase in a GPR30-dependent manner. Our findings suggest a novel signaling paradigm that is initiated by estrogen activation of the 7TM receptor GPR30, with signal transduction cascades (PI3K and MAPK) converging on nuclear hormone receptors (SF-1/LRH-1) to modulate their transcriptional output. We propose that this novel GPR30/SF-1 pathway increases local concentrations of estrogen, and together with classic ER signaling, mediate the proliferative effects of synthetic estrogens such as tamoxifen, in promoting endometriosis and endometrial cancers.

  7. Estrogen receptor-β in mitochondria: implications for mitochondrial bioenergetics and tumorigenesis.

    PubMed

    Liao, Tien-Ling; Tzeng, Chii-Ruey; Yu, Chao-Lan; Wang, Yi-Pei; Kao, Shu-Huei

    2015-09-01

    Estrogen enhances mitochondrial function by enhancing mitochondrial biogenesis and sustaining mitochondrial energy-transducing capacity. Shifts in mitochondrial bioenergetic pathways from oxidative phosphorylation to glycolysis have been hypothesized to be involved in estrogen-induced tumorigenesis. Studies have shown that mitochondria are an important target of estrogen. Estrogen receptor-β (ERβ) has been shown to localize to mitochondria in a ligand-dependent or -independent manner and can affect mitochondrial bioenergetics and anti-apoptotic signaling. However, the functional role of mitochondrial ERβ in tumorigenesis remains unclear. Clinical studies of ERβ-related tumorigenesis have shown that ERβ stimulates mitochondrial metabolism to meet the high energy demands of processes such as cell proliferation, cell survival, and transformation. Thus, in elucidating the precise role of mitochondrial ERβ in cell transformation and tumorigenesis, it will be particularly valuable to explore new approaches for the development of medical treatments targeting mitochondrial ERβ-mediated mitochondrial function and preventing apoptosis. © 2015 New York Academy of Sciences.

  8. Aroclor1254 interferes with estrogen receptor-mediated neuroprotection against beta-amyloid toxicity in cholinergic SN56 cells.

    PubMed

    Bang, Yeojin; Lim, Juhee; Kim, Sa Suk; Jeong, Hyung Min; Jung, Ki-Kyung; Kang, Il-Hyun; Lee, Kwang-Youl; Choi, Hyun Jin

    2011-10-01

    Because estrogen plays important neurotrophic and neuroprotective roles in the brain by activating estrogen receptors (ERs), disruption of normal estrogen signaling can leave neurons vulnerable to a variety of insults, including β-amyloid peptide (Aβ). Aroclor1254 (A1254) belongs to the endocrine-disrupting chemical (EDC) polychlorinated biphenyls and has anti-estrogenic properties. In the present study, we evaluated the effect of A1254 on the protective activity of estrogen against Aβ toxicity in differentiated cholinergic SN56 cells. Aged Aβ25-35 causes apoptotic cell death in differentiated SN56 cells, and the cytotoxic evidences are effectively rescued by estrogen. We found that A1254 abolishes the neuroprotective activity of estrogen against Aβ toxicity, and attenuates the suppressive effect of estrogen on Aβ-induced tau phosphorylation and JNK activation. The effects of A1254 on the neuroprotective effects of estrogen in Aβ toxicity are very similar to the effects of the estrogen receptor antagonist ICI182,780. Thus, exposure to EDCs that have anti-estrogenic activity might interfere with normal estrogen-activated neuroprotective signaling events and leave neurons more vulnerable to dangerous stimuli. Our present results provide new understanding of the mechanisms contributing to the harmful effects of EDCs on the function and viability of neurons, and the possible relevance of EDCs in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. RELATIVE BINDING AFFINITY OF ALKYLPHENOLS TO RAINBOW TROUT ESTROGEN RECEPTOR

    EPA Science Inventory

    RELATIVE BINDING AFFINITY OF ALKYLPHENOLS TO RAINBOW TROUT ESTROGEN RECEPTOR. T R Henry1, J S Denny2 and P K Schmieder2. USEPA, ORD, NHEERL, 1Experimental Toxicology Division and 2Mid-Continent Ecology Division, Duluth, MN, USA.
    The USEPA has been mandated to screen industria...

  10. A selective estrogen receptor modulator for the treatment of hot flushes.

    PubMed

    Wallace, Owen B; Lauwers, Kenneth S; Dodge, Jeffrey A; May, Scott A; Calvin, Joel R; Hinklin, Ronald; Bryant, Henry U; Shetler, Pamela K; Adrian, Mary D; Geiser, Andrew G; Sato, Masahiko; Burris, Thomas P

    2006-02-09

    A selective estrogen receptor modulator (SERM) for the potential treatment of hot flushes is described. (R)-(+)-7,9-difluoro-5-[4-(2-piperidin-1-ylethoxy)phenyl]-5H-6-oxachrysen-2-ol, LSN2120310, potently binds ERalpha and ERbeta and is an antagonist in MCF-7 breast adenocarcinoma and Ishikawa uterine cancer cell lines. The compound is a potent estrogen antagonist in the rat uterus. In ovariectomized rats, the compound lowers cholesterol, maintains bone mineral density, and is efficacious in a morphine dependent rat model of hot flush efficacy.

  11. MIBE acts as antagonist ligand of both estrogen receptor α and GPER in breast cancer cells

    PubMed Central

    2012-01-01

    Introduction The multiple biological responses to estrogens are mainly mediated by the classical estrogen receptors ERα and ERβ, which act as ligand-activated transcription factors. ERα exerts a main role in the development of breast cancer; therefore, the ER antagonist tamoxifen has been widely used although its effectiveness is limited by de novo and acquired resistance. Recently, GPR30/GPER, a member of the seven-transmembrane G protein-coupled receptor family, has been implicated in mediating the effects of estrogens in various normal and cancer cells. In particular, GPER triggered gene expression and proliferative responses induced by estrogens and even ER antagonists in hormone-sensitive tumor cells. Likewise, additional ER ligands showed the ability to bind to GPER eliciting promiscuous and, in some cases, opposite actions through the two receptors. We synthesized a novel compound (ethyl 3-[5-(2-ethoxycarbonyl-1-methylvinyloxy)-1-methyl-1H-indol-3-yl]but-2-enoate), referred to as MIBE, and investigated its properties elicited through ERα and GPER in breast cancer cells. Methods Molecular modeling, binding experiments and functional assays were performed in order to evaluate the biological action exerted by MIBE through ERα and GPER in MCF7 and SkBr3 breast cancer cells. Results MIBE displayed the ability to act as an antagonist ligand for ERα and GPER as it elicited inhibitory effects on gene transcription and growth effects by binding to both receptors in breast cancer cells. Moreover, GPER was required for epidermal growth factor receptor (EGFR) and ERK activation by EGF as ascertained by using MIBE and performing gene silencing experiments. Conclusions Our findings provide novel insights on the functional cross-talk between GPER and EGFR signaling. Furthermore, the exclusive antagonistic activity exerted by MIBE on ERα and GPER could represent an innovative pharmacological approach targeting breast carcinomas which express one or both receptors at

  12. MIBE acts as antagonist ligand of both estrogen receptor α and GPER in breast cancer cells.

    PubMed

    Lappano, Rosamaria; Santolla, Maria Francesca; Pupo, Marco; Sinicropi, Maria Stefania; Caruso, Anna; Rosano, Camillo; Maggiolini, Marcello

    2012-01-17

    The multiple biological responses to estrogens are mainly mediated by the classical estrogen receptors ERα and ERβ, which act as ligand-activated transcription factors. ERα exerts a main role in the development of breast cancer; therefore, the ER antagonist tamoxifen has been widely used although its effectiveness is limited by de novo and acquired resistance. Recently, GPR30/GPER, a member of the seven-transmembrane G protein-coupled receptor family, has been implicated in mediating the effects of estrogens in various normal and cancer cells. In particular, GPER triggered gene expression and proliferative responses induced by estrogens and even ER antagonists in hormone-sensitive tumor cells. Likewise, additional ER ligands showed the ability to bind to GPER eliciting promiscuous and, in some cases, opposite actions through the two receptors. We synthesized a novel compound (ethyl 3-[5-(2-ethoxycarbonyl-1-methylvinyloxy)-1-methyl-1H-indol-3-yl]but-2-enoate), referred to as MIBE, and investigated its properties elicited through ERα and GPER in breast cancer cells. Molecular modeling, binding experiments and functional assays were performed in order to evaluate the biological action exerted by MIBE through ERα and GPER in MCF7 and SkBr3 breast cancer cells. MIBE displayed the ability to act as an antagonist ligand for ERα and GPER as it elicited inhibitory effects on gene transcription and growth effects by binding to both receptors in breast cancer cells. Moreover, GPER was required for epidermal growth factor receptor (EGFR) and ERK activation by EGF as ascertained by using MIBE and performing gene silencing experiments. Our findings provide novel insights on the functional cross-talk between GPER and EGFR signaling. Furthermore, the exclusive antagonistic activity exerted by MIBE on ERα and GPER could represent an innovative pharmacological approach targeting breast carcinomas which express one or both receptors at the beginning and/or during tumor

  13. The Estrogen Receptor-α in Osteoclasts Mediates the Protective Effects of Estrogens on Cancellous But Not Cortical Bone

    PubMed Central

    Martin-Millan, Marta; Almeida, Maria; Ambrogini, Elena; Han, Li; Zhao, Haibo; Weinstein, Robert S.; Jilka, Robert L.; O'Brien, Charles A.; Manolagas, Stavros C.

    2010-01-01

    Estrogens attenuate osteoclastogenesis and stimulate osteoclast apoptosis, but the molecular mechanism and contribution of these effects to the overall antiosteoporotic efficacy of estrogens remain controversial. We selectively deleted the estrogen receptor (ER)α from the monocyte/macrophage cell lineage in mice (ERαLysM−/−) and found a 2-fold increase in osteoclast progenitors in the marrow and the number of osteoclasts in cancellous bone, along with a decrease in cancellous bone mass. After loss of estrogens these mice failed to exhibit the expected increase in osteoclast progenitors, the number of osteoclasts in bone, and further loss of cancellous bone. However, they lost cortical bone indistinguishably from their littermate controls. Mature osteoclasts from ERαLysM−/− were resistant to the proapoptotic effect of 17β-estradiol. Nonetheless, the effects of estrogens on osteoclasts were unhindered in mice bearing an ERα knock-in mutation that prevented binding to DNA. Moreover, a polymeric form of estrogen that is not capable of stimulating the nuclear-initiated actions of ERα was as effective as 17β-estradiol in inducing osteoclast apoptosis in cells with the wild-type ERα. We conclude that estrogens attenuate osteoclast generation and life span via cell autonomous effects mediated by DNA-binding-independent actions of ERα. Elimination of these effects is sufficient for loss of bone in the cancellous compartment in which complete perforation of trabeculae by osteoclastic resorption precludes subsequent refilling of the cavities by the bone-forming osteoblasts. However, additional effects of estrogens on osteoblasts, osteocytes, and perhaps other cell types are required for their protective effects on the cortical compartment, which constitutes 80% of the skeleton. PMID:20053716

  14. Androgens and estrogens in benign prostatic hyperplasia: past, present and future

    PubMed Central

    Nicholson, Tristan M.; Ricke, William A.

    2011-01-01

    Benign prostatic hyperplasia (BPH) and associated lower urinary tract symptoms (LUTS) are common clinical problems in urology. While the precise molecular etiology remains unclear, sex steroids have been implicated in the development and maintenance of BPH. Sufficient data exists linking androgens and androgen receptor pathways to BPH and use of androgen reducing compounds, such as 5α-reductase inhibitors which block the conversion of testosterone into dihydrotestosterone, are a component of the standard of care for men with LUTS attributed to an enlarged prostate. However, BPH is a multifactorial disease and not all men respond well to currently available treatments, suggesting factors other than androgens are involved. Testosterone, the primary circulating androgen in men, can also be metabolized via CYP19/aromatase into the potent estrogen, estradiol-17β. The prostate is an estrogen target tissue and estrogens directly and indirectly affect growth and differentiation of prostate. The precise role of endogenous and exogenous estrogens in directly affecting prostate growth and differentiation in the context of BPH is an understudied area. Estrogens and selective estrogen receptor modulators (SERMs) have been shown to promote or inhibit prostate proliferation signifying potential roles in BPH. Recent research has demonstrated that estrogen receptor signaling pathways may be important in the development and maintenance of BPH and LUTS; however, new models are needed to genetically dissect estrogen regulated molecular mechanisms involved in BPH. More work is needed to identify estrogens and associated signaling pathways in BPH in order to target BPH with dietary and therapeutic SERMs. PMID:21620560

  15. Dissociated overexpression of cathepsin D and estrogen receptor alpha in preinvasive mammary tumors.

    PubMed

    Roger, P; Daures, J P; Maudelonde, T; Pignodel, C; Gleizes, M; Chapelle, J; Marty-Double, C; Baldet, P; Mares, P; Laffargue, F; Rochefort, H

    2000-05-01

    The role of estrogen as a promoter agent of sporadic breast cancer has been considered by assaying, in benign breast disease (BBD) and in situ carcinomas (CIS), 2 markers, the estrogen receptor alpha (ERalpha) and cathepsin D (cath-D) involved in estrogen action on mammary tissue. ERalpha and cath-D were assayed by quantitative immunohistochemistry using an image analyzer in 170 lesions of varying histological risk (94 BBD and 76 CIS), and in "normal" glands close to these lesions. The ERalpha level increased significantly in proliferative BBD with atypia (P < .001), in non-high-grade CIS (P < .001), and in adjacent "normal" glands. ERalpha level was decreased in high-grade ductal CIS (DCIS) and also in adjacent "normal" glands. Cath-D level increased in ductal proliferative BBD (P < or = .01) and in high-grade DCIS (P < or = .003), but not in the other lesions. After menopause, ERalpha level was increased (P = .012) but not cath-D level. According to Mac Neman test, the high-grade DCIS were predominantly ERalpha negative and cath-D positive (P = .0017), and the other CIS were predominantly ERalpha positive and cath-D negative (P = .0002). The 2 markers are overexpressed early in premalignant lesions, but independently. This dissociation suggests a branched model of mammary carcinogenesis involving 1 estrogen-independent pathway with high cath-D and low ERalpha levels (including high-grade DCIS) and 1 estrogen-dependent pathway, with high ERalpha level (including proliferative BBD with atypia and low-grade DCIS). We propose that ERalpha-negative breast cancers may develop directly from high-grade DCIS and that ERalpha assay in preinvasive lesions should be considered in prevention trials with antiestrogens.

  16. Induction of osteoblast differentiation by selective activation of kinase-mediated actions of the estrogen receptor.

    PubMed

    Kousteni, Stavroula; Almeida, Maria; Han, Li; Bellido, Teresita; Jilka, Robert L; Manolagas, Stavros C

    2007-02-01

    Estrogens control gene transcription by cis or trans interactions of the estrogen receptor (ER) with target DNA or via the activation of cytoplasmic kinases. We report that selective activation of kinase-mediated actions of the ER with 4-estren-3alpha,17beta-diol (estren) or an estradiol-dendrimer conjugate, each a synthetic compound that stimulates kinase-mediated ER actions 1,000 to 10,000 times more potently than direct DNA interactions, induced osteoblastic differentiation in established cell lines of uncommitted osteoblast precursors and primary cultures of osteoblast progenitors by stimulating Wnt and BMP-2 signaling in a kinase-dependent manner. In sharp contrast, 17beta-estradiol (E(2)) suppressed BMP-2-induced osteoblast progenitor commitment and differentiation. Consistent with the in vitro findings, estren, but not E(2), stimulated Wnt/beta-catenin-mediated transcription in T-cell factor-lacZ transgenic mice. Moreover, E(2) stimulated BMP signaling in mice in which ERalpha lacks DNA binding activity and classical estrogen response element-mediated transcription (ERalpha(NERKI/-)) but not in wild-type controls. This evidence reveals for the first time the existence of a large signalosome in which inputs from the ER, kinases, bone morphogenetic proteins, and Wnt signaling converge to induce differentiation of osteoblast precursors. ER can either induce it or repress it, depending on whether the activating ligand (and presumably the resulting conformation of the receptor protein) precludes or accommodates ERE-mediated transcription.

  17. Estrogen Receptor Mutants/Variants in Human Breast Cancer.

    DTIC Science & Technology

    1995-12-01

    Effect of dystrophin gene deletions on mRNA levels and processing in Duchenne and Becker dystrophies . Cell 1990, 63:1239-1248 4 Patriotis C, Makris A...the most common inherited disorder of platelets, Aspartylblucosaminuria, 2 an inherited lysosomal storage disorder, Duchenne and Becker muscular... dystrophies 3 or cancer progression.4m 5 Several estrogen receptor (ER) variant mRNAs have also been identified in human breast cancer biopsies.6,7,8, 9

  18. G protein-coupled receptor 30 expression is up-regulated by EGF and TGF alpha in estrogen receptor alpha-positive cancer cells.

    PubMed

    Vivacqua, Adele; Lappano, Rosamaria; De Marco, Paola; Sisci, Diego; Aquila, Saveria; De Amicis, Francesca; Fuqua, Suzanne A W; Andò, Sebastiano; Maggiolini, Marcello

    2009-11-01

    In the present study, we evaluated the regulation of G protein-coupled receptor (GPR)30 expression in estrogen receptor (ER)-positive endometrial, ovarian, and estrogen-sensitive, as well as tamoxifen-resistant breast cancer cells. We demonstrate that epidermal growth factor (EGF) and TGF alpha transactivate the GPR30 promoter and accordingly up-regulate GPR30 mRNA and protein levels only in endometrial and tamoxifen-resistant breast cancer cells. These effects exerted by EGF and TGF alpha were dependent on EGF receptor (EGFR) expression and activation and involved phosphorylation of the Tyr(1045) and Tyr(1173) EGFR sites. Using gene-silencing experiments and specific pharmacological inhibitors, we have ascertained that EGF and TGF alpha induce GPR30 expression through the EGFR/ERK transduction pathway, and the recruitment of c-fos to the activator protein-1 site located within GPR30 promoter sequence. Interestingly, we show that functional cross talk of GPR30 with both activated EGFR and ER alpha relies on a physical interaction among these receptors, further extending the potential of estrogen to trigger a complex stimulatory signaling network in hormone-sensitive tumors. Given that EGFR/HER2 overexpression is associated with tamoxifen resistance, our data may suggest that ligand-activated EGFR could contribute to the failure of tamoxifen therapy also by up-regulating GPR30, which in turn could facilitates the action of estrogen. In addition, important for resistance is the ability of tamoxifen to bind to and activate GPR30, the expression of which is up-regulated by EGFR activation. Our results emphasize the need for new endocrine agents able to block widespread actions of estrogen without exerting any stimulatory activity on transduction pathways shared by the steroid and growth factor-signaling networks.

  19. Retrograde transport of the transmembrane estrogen receptor, G-protein-coupled-receptor-30 (GPR30/GPER) from the plasma membrane towards the nucleus.

    PubMed

    Cheng, Shi-Bin; Graeber, Carl T; Quinn, Jeffrey A; Filardo, Edward J

    2011-08-01

    G-protein-coupled receptor 30 (GPR30/GPER) belongs to the seven transmembrane receptor (7TMR) superfamily, the most common class of surface receptor with approximately 800 known members. GPER promotes estrogen binding and rapid signaling via membrane-associated enzymes resulting in increased cAMP and release of heparan bound epidermal growth factor (proHB-EGF) from breast cancer cells. However, GPER is predominately localized intracellularly in breast cancer cells with minor amounts of receptor on the cell surface, an observation that has caused some controversy regarding its potential role as a plasma membrane estrogen receptor. Using the widely employed approach of tracking recombinant 7TMRs by surface labeling live cells, we have begun to characterize and compare the endocytic fate of GPER to other similarly labeled 7TMRs. Upon ectopic expression in human embryonic kidney HEK-293 cells, functional GPER is generated as these cells acquire the capacity to stimulate cAMP and activate cyclic AMP responsive binding protein in response to estradiol-17 beta stimulation. GPER is detectable on the cell surface by immunofluorescent analysis using HA-specific antibodies, albeit the bulk of the receptor is located intracellularly. Like β1AR (beta 1 adrenergic receptor) and CXCR4 (C-X-C chemokine receptor 4), GPER exits the plasma membrane via clathrin-coated pits and enters early endosomes. Interestingly, GPER has a destination that is uncommon among 7TMRs, as it accumulates in a perinuclear compartment. Like many 7TMRs (approximately one-third), GPER trafficking from the plasma membrane is constitutive (occurs in the absence of agonist). However, its route of intracellular trafficking is highly unusual, as 7TMRs typically recycle to the plasma membrane (e.g. β1AR) or are degraded in lysosomes (e.g. CXCR4). The accumulation of GPER in the perinuclear space and its possible significance for attenuating estrogen action via this newly recognized membrane estrogen receptor is

  20. Estrogen receptor modulatory effects of germinated brown rice bioactives in the uterus of rats through the regulation of estrogen-induced genes

    PubMed Central

    Muhammad, Sani Ismaila; Maznah, Ismail; Mahmud, Rozi Bint; Saeed, Mohammed Ibrahim; Imam, Mustapha Umar; Ishaka, Aminu

    2013-01-01

    Purpose The expression of genes regulated by estrogen in the uterus was studied in ovariectomized (OVX) rats treated with germinated brown rice (GBR) bioactives, and compared to Remifemin or estrogen at different doses to identify the regulation of these genes in the uterus and their molecular mechanisms. Methods Rats were treated orally with GBR bioactives (phenolics), acylated steryl glucosides (ASG), γ-amino butyric acid (GABA), and γ-oryzanol (ORZ) at 100 and 200 mg/kg, Remifemin (REM) at 10 mg/kg and 20 mg/kg, or estrogen (EST) at 0.2 mg/kg. Ribonucleic acid (RNA) was extracted from the uterus, and messenger (m)RNA expression of selected genes encoding estrogen receptor-beta (ER-β), calcium-binding protein (CaBP9k), complement protein (C3), heat shock protein 70 kDa (HSP70), and interleukin (IL)-4 receptor were quantified. Similarly, serum steroid hormone concentration was monitored at 2, 4, and 8 weeks after treatments. ER-β antibody binding to the uterus sections was also studied using immunohistochemistry. Results The group treated with EST (0.2 mg/kg) upregulated ER-β, C3, and IL-4 receptor genes compared to other groups (P<0.001). GBR phenolics (200 mg/kg) treatment upregulated the ER-β gene almost to the level of the sham non-treated group. The CaBP9k gene showed upregulation in groups treated with ASG (200 mg/kg), EST (0.2 mg/kg), and ORZ (200 mg/kg) (P<0.05). Estrogen levels increased in groups treated with EST, ASG, and ORZ (200 mg/kg) compared to the OVX untreated group (P<0.05), and there was a slight non-significant decrease (P>0.05) in the progesterone levels in the OVX untreated group compared to the sham and other treated groups. There was a significant increase at 8 weeks in the level of FSH (P<0.05) in the treated groups compared to the OVX untreated group. There was no significant difference (P>0.05) in serum luteinizing hormone (LH) between the OVX untreated group and other groups. The sham and GBR phenolics treated group showed ER

  1. Epithelial estrogen receptor 1 intrinsically mediates squamous differentiation in the mouse vagina

    PubMed Central

    Miyagawa, Shinichi; Iguchi, Taisen

    2015-01-01

    Estrogen-mediated actions in female reproductive organs are tightly regulated, mainly through estrogen receptor 1 (ESR1). The mouse vaginal epithelium cyclically exhibits cell proliferation and differentiation in response to estrogen and provides a unique model for analyzing the homeostasis of stratified squamous epithelia. To address the role of ESR1-mediated tissue events during homeostasis, we analyzed mice with a vaginal epithelium-specific knockout of Esr1 driven by keratin 5-Cre (K5-Esr1KO). We show here that loss of epithelial ESR1 in the vagina resulted in aberrant epithelial cell proliferation in the suprabasal cell layers and led to failure of keratinized differentiation. Gene expression analysis showed that several known estrogen target genes, including erbB growth factor ligands, were not induced by estrogen in the K5-Esr1KO mouse vagina. Organ culture experiments revealed that the addition of erbB growth factor ligands, such as amphiregulin, could activate keratinized differentiation in the absence of epithelial ESR1. Thus, epithelial ESR1 integrates estrogen and growth factor signaling to mediate regulation of cell proliferation in squamous differentiation, and our results provide new insights into estrogen-mediated homeostasis in female reproductive organs. PMID:26438838

  2. Estrogen receptors and the metabolic network.

    PubMed

    Barros, Rodrigo P A; Gustafsson, Jan-Åke

    2011-09-07

    The metabolic syndrome has reached pandemic level worldwide, and evidence is that estradiol plays a key role in its development. The discovery of the second estrogen receptor, ERβ, in tissues previously not considered targets of estradiol was a breakthrough in endocrinology. In the present review, we discuss how the presence of ERβ and the previously described ERα in tissues involved in glucose and lipid homeostasis (brain, skeletal muscle, adipose tissue, pancreas, liver, and heart) may have important implications to risk factors associated with the metabolic syndrome. Imbalance of ERα/ERβ ratio in this "metabolic network" may lead to the metabolic syndrome. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Distinct effects of loss of classical estrogen receptor signaling versus complete deletion of estrogen receptor alpha on bone

    PubMed Central

    Syed, Farhan A.; Fraser, Daniel G.; Monroe, David G.; Khosla, Sundeep

    2011-01-01

    Estrogen receptor (ER)α is a major regulator of bone metabolism which can modulate gene expression via a “classical” pathway involving direct DNA binding to estrogen-response elements (EREs) or via “non-classical” pathways involving protein-protein interactions. While the skeletal consequences of loss of ERE binding by ERα have been described, a significant unresolved question is how loss of ERE binding differs from complete loss of ERα. Thus, we compared the skeletal phenotype of wild-type (ERα+/+) and ERα knock out (ERα−/−) mice with that of mice in which the only ERα present had a knock-in mutation abolishing ERE binding (non-classical ERα knock-in [NERKI], ERα−/NERKI). All three groups were in the same genetic background (C57BL/6). As compared to both ERα+/+ and ERα−/− mice, ERα−/NERKI mice had significantly reduced cortical volumetric bone mineral density and thickness at the tibial diaphysis; this was accompanied by significant decreases in periosteal and endocortical mineral apposition rates. Colony forming unit (CFU)-fibroblast, CFU-alkaline phosphatase, and CFU-osteoblast numbers were all increased in ERα−/− compared to ERα+/+ mice, but reduced in ERα−/NERKI mice compared to the two other groups. Thus, using mice in identical genetic backgrounds, our data indicate that the presence of an ERα that cannot bind DNA but can function through protein-protein interactions may have more deleterious skeletal effects than complete loss of ERα. These findings suggest that shifting the balance of classical versus non-classical ERα signaling triggers pathways that impair bone formation. Further studies defining these pathways may lead to novel approaches to selectively modulate ER signaling for beneficial skeletal effects. PMID:21458604

  4. Estrogen receptors and cathepsin D in human thyroid tissue.

    PubMed

    Métayé, T; Millet, C; Kraimps, J L; Aubouin, B; Barbier, J; Bégon, F

    1993-09-15

    To investigate the significance of estrogen receptors (ER) in the pathogenesis of thyroid dysplasia, the authors analyzed, by analogy with breast cancers, ER and three estrogen-regulated proteins: progesterone receptor (PR), cathepsin D, and pS2 protein, in cytosols of 42 human thyroid tissues. ER and PR were measured by an immunoenzymatic assay and cathepsin D and pS2 by an immunoradiometric assay. Tissue specimens included 7 normal tissues, 6 benign nodules, 8 toxic adenomas, 7 from patients with Graves disease, and 14 carcinomas. ER was present at very low concentrations, with no statistical difference between neoplastic and nonneoplastic tissues. The mean levels of cathepsin D, expressed as pmol/mg protein minus thyroglobulin, were higher in the 14 carcinomas (P = 0.0003), the 7 specimens from patients with Graves disease (P = 0.006), and the 8 toxic adenomas (P = 0.04) than in the 7 normal thyroid tissues. A significant difference also was observed between the carcinomas (P = 0.003) and six benign nodules. Compared to TNM parameters, cathepsin D concentrations correlated with tumor size: higher cathepsin D levels were found in pT4 than in pT2 and pT3 carcinomas. All the tissues tested were negative for PR and pS2 protein. The results clearly indicate a significant difference between neoplastic and normal thyroid tissue in terms of the amount of cathepsin D, but not that of ER. This suggests that cathepsin D probably is not regulated by estrogen but simply is a marker of protease activity during invasion by thyroid carcinomas.

  5. The selective estrogen receptor modulators in breast cancer prevention.

    PubMed

    Li, Fangxuan; Dou, Jinli; Wei, Lijuan; Li, Shixia; Liu, Juntian

    2016-05-01

    Persistently increased blood levels of estrogens are associated with an increased risk of breast cancer. Selective estrogen receptor modulators (SERMs) are a class of compounds that act on the estrogen receptor (ER). Several clinical trials have demonstrated the effectiveness of its prophylactic administration. Incidence of invasive ER-positive breast cancer was reduced by SERMs treatment, especially for those women with high risk of developing breast cancer. In this study, we reviewed the clinical application of SERMs in breast cancer prevention. To date, four prospective randomized clinical trials had been performed to test the efficacy of tamoxifen for this purpose. Concerning on the benefit and cost of tamoxifen, various studies from different countries demonstrated that chemoprevention with tamoxifen seemed to be cost-effective for women with a high risk of invasive breast cancer. Based above, tamoxifen was approved for breast cancer prevention by the US Food and Drug Administration in 1998. Raloxifene was also approved for postmenopausal women in 2007 for breast cancer prevention which reduces the risk of invasive breast cancer with a lower risk of unwanted stimulation of endometrium. Thus, raloxifene is considered to have a better clinical possesses as prophylactic agent. Several other agents, such as arzoxifene and lasofoxifene, are currently being investigated in clinic. The American Society of Clinical Oncology and National Comprehensive Cancer Network had published guidelines on breast cancer chemoprevention by SERMs. However, use of tamoxifen and raloxifene for primary breast cancer prevention was still low. A broader educational effort is needed to alert women and primary care physicians that SERMs are available to reduce breast cancer risk.

  6. Gene therapy of uterine leiomyomas: adenovirus-mediated expression of dominant negative estrogen receptor inhibits tumor growth in nude mice.

    PubMed

    Al-Hendy, Ayman; Lee, Eun J; Wang, Hui Q; Copland, John A

    2004-11-01

    Leiomyomas (fibroids) are common estrogen-dependent uterine tumors with no effective medicinal treatment; hysterectomy is the mainstay of management. This study was undertaken to investigate a potential therapy for leiomyoma; we used a mutated dominant-negative estrogen receptor gene delivered via an adenoviral vector (Ad-ER-DN). Ad-ER-DN transduction, in both human and rat leiomyoma cell lines, induced an increase in both caspase-3 levels and BAX/Bcl-2 ratio with evident apoptosis in the TdT-mediated dUTP nick-end labeling assay. In nude mice, rat leiomyoma cells ex vivo transduced with Ad-ER-DN supported significantly smaller tumors compared with Ad-LacZ-treated cells 5 weeks after implantation. In mice treated by direct intratumor injection into preexisting lesions, Ad-ER-DN caused immediate overall arrest of tumor growth. The Ad-ER-DN-treated tumors demonstrated severely inhibited cell proliferation (BrdU index) and a marked increase in the number of apoptotic cells (TdT-mediated dUTP nick-end labeling index). Dominant-negative estrogen receptor gene therapy may provide a nonsurgical treatment option for women with symptomatic uterine fibroids who want to preserve their uteri.

  7. Activation of G protein-coupled receptor 30 by thiodiphenol promotes proliferation of estrogen receptor α-positive breast cancer cells.

    PubMed

    Lei, Bingli; Peng, Wei; Xu, Gang; Wu, Minghong; Wen, Yu; Xu, Jie; Yu, Zhiqiang; Wang, Yipei

    2017-02-01

    Many studies have been shown that environmental estrogen bisphenol A (BPA) can activate nuclear receptor (estrogen receptor alpha, ERα) or membrane receptor (G-protein-coupled receptor, GPR30) in breast cancer cells and exerts genomic or nongenomic actions inducing cell proliferation. 4,4'-thiodiphenol (TDP) as one of BPA derivatives exhibits more potent estrogenic activity than BPA does. However, comparatively little is known about the ways in which TDP interferes with these signaling pathways and produces cell biological changes. This study evaluated the effect of TDP on cell viability, reactive oxygen species (ROS) formation, and intercellular calcium (Ca 2+ ) fluctuation in MCF-7 breast cancer cells. The underlying molecular mechanism of cell proliferation induced by TDP was analyzed by examining the activation of ERα and GPR30-mediated phosphatidylinotidol 3-kinase/protein kinase B (PI3K/AKT) and extracellular-signa1regulated kinase (ERK1/2) signaling pathways. The results showed that exposure to 0.1-10 μM TDP for 24, 48, and 72 h significantly increased viability of MCF-7 cells. At the same concentration range, TDP exposure for 3 and 24 h markedly elevated ROS production and intracellular Ca 2+ levels. In addition, 0.01-1 μM TDP significantly increased the expression of ERα, GPR30, p-AKT and p-ERK1/2 protein. Specific protein inhibitors blocked phosphorylation of ERK1/2 and AKT and decreased TDP-induced cell proliferation. These findings show that TDP activated the GPR30-PI3K/AKT and ERK1/2 pathways, and the resulting interaction with ERα stimulated MCF-7 cell proliferation. Our results indicate a novel mechanism through which TDP may exert relevant estrogenic action in ERα positive cancer cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Expression pattern and signalling pathways in neutrophil like HL-60 cells after treatment with estrogen receptor selective ligands.

    PubMed

    Blesson, Chellakkan Selvanesan; Sahlin, Lena

    2012-09-25

    Estrogens play a role in the regulation of genes associated with inflammation and immunity in neutrophils. Estrogen signalling is mediated by estrogen receptor (ER)α, ERβ, and G-protein-coupled estrogen receptor-1 (GPER). The mechanisms by which estrogen regulate genes in neutrophils are poorly understood. Our aim was to identify the presence of ERs and to characterize estrogen responsive genes in terminally differentiated neutrophil like HL-60 (nHL-60) cells using estradiol and selective ER agonists. ERs were identified by Western blotting and immunocytochemistry. Microarray technique was used to screen for differentially expressed genes and the selected genes were verified by quantitative PCR. We show the presence of functional ERα, ERβ and GPER. Microarray analysis showed the presence of genes that are uniquely regulated by a single ligand and also genes that are regulated by multiple ligands. We conclude that ERs are functionally active in nHL-60 cells regulating genes involved in key physiological functions. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  9. The G-protein coupled estrogen receptor, GPER: The inside and inside-out story.

    PubMed

    Gaudet, H M; Cheng, S B; Christensen, E M; Filardo, E J

    2015-12-15

    GPER possesses structural and functional characteristics shared by members of the G-protein-coupled receptor (GPCR) superfamily, the largest class of plasma membrane receptors. This newly appreciated estrogen receptor is localized predominately within intracellular membranes in most, but not all, cell types and its surface expression is modulated by steroid hormones and during tissue injury. An intracellular staining pattern is not unique among GPCRs, which employ a diverse array of molecular mechanisms that restrict cell surface expression and effectively regulating receptor binding and activation. The finding that GPER displays an intracellular predisposition has created some confusion as the estrogen-inducible transcription factors, ERα and ERβ, also reside intracellularly, and has led to complex suggestions of receptor interaction. GPER undergoes constitutive retrograde trafficking from the plasma membrane to the endoplasmic reticulum and recent studies indicate its interaction with PDZ binding proteins that sort transmembrane receptors to synaptosomes and endosomes. Genetic targeting and selective ligand approaches as well as cell models that express GPER in the absence of ERs clearly supports GPER as a bonafide "stand alone" receptor. Here, the molecular details that regulate GPER action, its cell biological activities and its implicated roles in physiological and pathological processes are reviewed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. An estrogen receptor β-selective agonist inhibits non-alcoholic steatohepatitis in preclinical models by regulating bile acid and xenobiotic receptors.

    PubMed

    Ponnusamy, Suriyan; Tran, Quynh T; Thiyagarajan, Thirumagal; Miller, Duane D; Bridges, Dave; Narayanan, Ramesh

    2017-03-01

    Non-alcoholic steatohepatitis (NASH) affects 8-10 million people in the US and up to 75% of obese individuals. Despite this, there are no approved oral therapeutics to treat NASH and therefore the need for novel approaches exists. The estrogen receptor β (ER-β)-selective agonist, β-LGND2, inhibits body weight and white adipose tissue, and increases metabolism, resulting in higher energy expenditure and thermogenesis. Due to favorable effects of β-LGND2 on obesity, we hypothesized that β-LGND2 will prevent NASH directly by reducing lipid accumulation in the liver or indirectly by favorably changing body composition. Male C57BL/6 mice fed with high fat diet (HFD) for 10 weeks or methionine choline-deficient diet for four weeks and treated with vehicle exhibited altered liver weights by twofold and increased serum transaminases by 2-6-folds. These changes were not observed in β-LGND2-treated animals. Infiltration of inflammatory cells and collagen deposits, an indication of fibrosis, were observed in the liver of mice fed with HFD for 10 weeks, which were effectively blocked by β-LGND2. Gene expression studies in the liver indicate that pregnane X receptor target genes were significantly increased by HFD, and the increase was inhibited by β-LGND2. On the other hand, metabolomics indicate that bile acid metabolites were significantly increased by β-LGND2. These studies demonstrate that an ER-β agonist might provide therapeutic benefits in NASH by directly modulating the function of xenobiotic and bile acid receptors in the liver, which have important functions in the liver, and indirectly, as demonstrated before, by inhibiting adiposity. Impact statement Over 75-90% of those classified as clinically obese suffer from co-morbidities, the most common of which is non-alcoholic steatohepatitis (NASH). While there are currently no effective treatment approaches for NASH, data presented here provide preliminary evidence that an estrogen receptor β-selective ligand

  11. Selective Estrogen Receptor Modulation Increases Hippocampal Activity during Probabilistic Association Learning in Schizophrenia

    PubMed Central

    Kindler, Jochen; Weickert, Cynthia Shannon; Skilleter, Ashley J; Catts, Stanley V; Lenroot, Rhoshel; Weickert, Thomas W

    2015-01-01

    People with schizophrenia show probabilistic association learning impairment in conjunction with abnormal neural activity. The selective estrogen receptor modulator (SERM) raloxifene preserves neural activity during memory in healthy older men and improves memory in schizophrenia. Here, we tested the extent to which raloxifene modifies neural activity during learning in schizophrenia. Nineteen people with schizophrenia participated in a twelve-week randomized, double-blind, placebo-controlled, cross-over adjunctive treatment trial of the SERM raloxifene administered orally at 120 mg daily to assess brain activity during probabilistic association learning using functional magnetic resonance imaging (fMRI). Raloxifene improved probabilistic association learning and significantly increased fMRI BOLD activity in the hippocampus and parahippocampal gyrus relative to placebo. A separate region of interest confirmatory analysis in 21 patients vs 36 healthy controls showed a positive association between parahippocampal neural activity and learning in patients, but no such relationship in the parahippocampal gyrus of healthy controls. Thus, selective estrogen receptor modulation by raloxifene concurrently increases activity in the parahippocampal gyrus and improves probabilistic association learning in schizophrenia. These results support a role for estrogen receptor modulation of mesial temporal lobe neural activity in the remediation of learning disabilities in both men and women with schizophrenia. PMID:25829142

  12. Correlation between erythropoietin receptor(s) and estrogen and progesterone receptor expression in different breast cancer cell lines.

    PubMed

    Trošt, Nina; Hevir, Neli; Rižner, Tea Lanišnik; Debeljak, Nataša

    2013-03-01

    Erythropoietin (EPO) receptor (EPOR) expression in breast cancer has been shown to correlate with the expression of estrogen receptor (ESR) and progesterone receptor (PGR) and to be associated with the response to tamoxifen in ESR+/PGR+ tumors but not in ESR- tumors. In addition, the correlation between EPOR and G protein-coupled estrogen receptor 1 [GPER; also known as G protein-coupled receptor 30 (GPR30)] has been reported, suggesting the prognostic potential of EPOR expression. Moreover, the involvement of colony stimulating factor 2 receptor, β, low‑affinity (CSF2RB) and ephrin type-B receptor 4 (EPHB4) as EPOR potential receptor partners in cancer has been indicated. This study analyzed the correlation between the expression of genes for EPO, EPOR, CSF2RB, EPHB4, ESR, PGR and GPER in the MCF-7, MDA-MB-361, T-47D, MDA-MB-231, Hs578Bst, SKBR3, MCF-10A and Hs578T cell lines. The cell lines were also treated with recombinant human EPO (rHuEPO) in order to determine its ability to activate the Jak/STAT5, MAPK and PI3K signaling pathways and modify cell growth characteristics. Expression analysis stratified the cell lines in 2 main clusters, hormone-dependent cell lines expressing ESR and PGR and a hormone-independent cluster. A significant correlation was observed between the expression levels of ESR and PGR and their expression was also associated with that of GPER. Furthermore, the expression of GPER was associated with that of EPOR, suggesting the connection between this orphan G protein and EPO signaling. A negative correlation between EPOR and CSF2RB expression was observed, questioning the involvement of these two receptors in the hetero-receptor formation. rHuEPO treatment only influenced the hormone-independent cell lines, since only the MDA-MB-231, SKBR3 and Hs578T cells responded to the treatment. The correlation between the expression of the analyzed receptors suggests that the receptors may interact in order to activate signaling pathways

  13. Estrogen receptor alpha polymorphisms and the risk of prostate cancer development.

    PubMed

    Jurečeková, Jana; Babušíková, Eva; Kmeťová, Monika; Kliment, Ján; Dobrota, Dušan

    2015-11-01

    The main purpose of the study was to evaluate the effect of two polymorphisms in the estrogen receptor alpha, rs2077647 and rs3798577, on the development of prostate cancer, their correlation with selected clinical characteristics, as well as consideration of potential interactions between four estrogen receptor alpha polymorphisms (rs2077647, rs3798577, PvuII, XbaI). The study was performed using 395 patients with histologically verified prostate cancer and 253 healthy male controls. The CC genotype of rs2077647 was significantly associated with prostate cancer (OR = 1.61). No association was found between rs3798577 polymorphism and prostate cancer. After stratification of patients according to the age at diagnosis and Gleason score, we observed significant correlation between rs2077647 polymorphism and prostate cancer risk in patients diagnosed before the age of 60 as well as patients with Gleason score <7, while rs3798577 was significantly associated with prostate cancer risk development in patients older than 60 and with Gleason score ≥7. Double analysis of each combination of four studied polymorphisms showed that presence of at least three variant alleles was associated with prostate cancer risk in all combinations, while each containing rs3798577 was significantly associated with development of high-grade carcinomas. The present study suggests that rs2077647 polymorphism may be a risk factor for prostate cancer especially in patients diagnosed before the age of 60, while rs3798577 polymorphism could probably serve rather as promoting factor in combination with other polymorphisms in estrogen receptor alpha contributing preferably to development of high-grade carcinomas.

  14. Inhibition of estrogen-responsive gene activation by the retinoid X receptor beta: evidence for multiple inhibitory pathways.

    PubMed

    Segars, J H; Marks, M S; Hirschfeld, S; Driggers, P H; Martinez, E; Grippo, J F; Brown, M; Wahli, W; Ozato, K

    1993-04-01

    The retinoid X receptor beta (RXR beta; H-2RIIBP) forms heterodimers with various nuclear hormone receptors and binds multiple hormone response elements, including the estrogen response element (ERE). In this report, we show that endogenous RXR beta contributes to ERE binding activity in nuclear extracts of the human breast cancer cell line MCF-7. To define a possible regulatory role of RXR beta regarding estrogen-responsive transcription in breast cancer cells, RXR beta and a reporter gene driven by the vitellogenin A2 ERE were transfected into estrogen-treated MCF-7 cells. RXR beta inhibited ERE-driven reporter activity in a dose-dependent and element-specific fashion. This inhibition occurred in the absence of the RXR ligand 9-cis retinoic acid. The RXR beta-induced inhibition was specific for estrogen receptor (ER)-mediated ERE activation because inhibition was observed in ER-negative MDA-MB-231 cells only following transfection of the estrogen-activated ER. No inhibition of the basal reporter activity was observed. The inhibition was not caused by simple competition of RXR beta with the ER for ERE binding, since deletion mutants retaining DNA binding activity but lacking the N-terminal or C-terminal domain failed to inhibit reporter activity. In addition, cross-linking studies indicated the presence of an auxiliary nuclear factor present in MCF-7 cells that contributed to RXR beta binding of the ERE. Studies using known heterodimerization partners of RXR beta confirmed that RXR beta/triiodothyronine receptor alpha heterodimers avidly bind the ERE but revealed the existence of another triiodothyronine-independent pathway of ERE inhibition. These results indicate that estrogen-responsive genes may be negatively regulated by RXR beta through two distinct pathways.

  15. Estrogen-dependent regulation of sodium/hydrogen exchanger-3 (NHE3) expression via estrogen receptor β in proximal colon of pregnant mice.

    PubMed

    Choijookhuu, Narantsog; Sato, Yoko; Nishino, Tomoya; Endo, Daisuke; Hishikawa, Yoshitaka; Koji, Takehiko

    2012-05-01

    Although constipation is very common during pregnancy, the exact mechanism is unknown. We hypothesized that the involvement of estrogen receptor (ER) in the regulation of electrolyte transporter in the colon leads to constipation. In this study, the intestines of normal female ICR mouse and pregnant mice were examined for the expression of ERα and ERβ by immunohistochemistry and in situ hybridization. ERβ, but not ERα, was expressed in surface epithelial cells of the proximal, but not distal, colon on pregnancy days 10, 15, and 18, but not day 5, and the number of ERβ-positive cells increased significantly during pregnancy. Expression of NHE3, the gene that harbors estrogen response element, examined by immunohistochemistry and western blotting, was localized in the surface epithelial cells of the proximal colon and increased in parallel with ERβ expression. In ovariectomized mice, NHE3 expression was only marginal and was up-regulated after treatment with 17β-estradiol (E(2)), but not E(2) + ICI 182,780 (estrogen receptor antagonist). Moreover, knock-down of ERβ expression by electroporetically transfected siRNA resulted in a significant reduction of NHE3 expression. These results indicate that ERβ regulates the expression of NHE3 in the proximal colon of pregnant mice through estrogen action, suggesting the involvement of increased sodium absorption by up-regulated NHE3 in constipation during pregnancy.

  16. Apoptosis of lactotrophs induced by D2 receptor activation is estrogen dependent.

    PubMed

    Radl, Daniela B; Zárate, Sandra; Jaita, Gabriela; Ferraris, Jimena; Zaldivar, Verónica; Eijo, Guadalupe; Seilicovich, Adriana; Pisera, Daniel

    2008-01-01

    Dopamine (DA) inhibits prolactin release and reduces lactotroph proliferation by activating D2 receptors. DA and its metabolite, 6-hydroxydopamine (6-OHDA), induce apoptosis in different cell types. DA receptors and DA transporter (DAT) were implicated in this action. Considering that estradiol sensitizes anterior pituitary cells to proapoptotic stimuli, we investigated the effect of estradiol on the apoptotic action of DA and 6-OHDA in anterior pituitary cells, and the involvement of the D2 receptor and DAT in the proapoptotic effect of DA. Viability of cultured anterior pituitary cells from ovariectomized rats was determined by MTS assay. Apoptosis was evaluated by Annexin-V/flow cytometry and TUNEL. Lactotrophs were identified by immunocytochemistry. DA induced apoptosis of lactotrophs in an estrogen-dependent manner. In contrast, estradiol was not required to trigger the apoptotic action of 6-OHDA. Cabergoline, a D2 receptor agonist, induced lactotroph apoptosis, while sulpiride, a D2 receptor antagonist, blocked DA-induced cell death. The blockade of DAT by GBR12909 did not affect the apoptotic action of DA, but inhibited 6-OHDA-induced apoptosis. These data show that DA, through D2 receptor activation, induces apoptosis of estrogen-sensitized anterior pituitary cells, and suggest that DA contributes to the control of lactotroph number not only by inhibiting proliferation but also by inducing apoptosis. 2008 S. Karger AG, Basel.

  17. NATURE OF BINDING INTERACTION OF SELECTED CHEMICALS WITH RAT ESTROGEN RECEPTORS

    EPA Science Inventory

    The US EPA is currently validating a rat uterine estrogen receptor (ER) binding assay as part of the Tier 1 Screening Battery for the Endocrine Disruptor Program. An eventual goal is to use interactive data to create computerized structure-activity models. However, more informati...

  18. Sexually Dimorphic Role of G Protein-Coupled Estrogen Receptor (GPER) in Modulating Energy Homeostasis

    PubMed Central

    Davis, Kathryn E.; Carstens, Elizabeth J.; Irani, Boman G.; Gent, Lana M.; Hahner, Lisa M.; Clegg, Deborah J.

    2014-01-01

    The classical estrogen receptors, estrogen receptor-α and estrogen receptor-β are well established in the regulation of body weight and energy homeostasis in both male and female mice, whereas, the role for G protein-coupled estrogen receptor 1 (GPER) as a modulator of energy homeostasis remains controversial. This study sought to determine whether gene deletion of GPER (GPER KO) alters body weight, body adiposity, food intake, and energy homeostasis in both males and females. Male mice lacking GPER developed moderate obesity and larger adipocyte size beginning at 8 weeks of age, with significant reductions in energy expenditure, but not food intake or adipocyte number. Female GPER KO mice developed increased body weight relative to WT females a full 6 weeks later than the male GPER KO mice. Female GPER KO mice also had reductions in energy expenditure, but not significant increases in body fat content. Consistent with their decrease in energy expenditure, GPER KO males and females showed significant reductions in two brown fat thermogenic proteins. GPER KO females, prior to their divergence in body weight, were less sensitive than WT females to the feeding-inhibitory effects of leptin and CCK. Additionally, body weight was not as modulated by ovariectomy or estradiol replacement in GPER KO mice. Estradiol treatment activated phosphorylated extracellular signal-regulated kinase (pERK) in WT but not GPER KO females. For the first time, GPER expression was found in the adipocyte but not the stromal fraction of adipose tissue. Together, these results provide new information elucidating a sexual dimorphism in GPER function in the development of postpubertal energy balance. PMID:24560890

  19. Progesterone receptor isoforms, agonists and antagonists differentially reprogram estrogen signaling

    PubMed Central

    Singhal, Hari; Greene, Marianne E.; Zarnke, Allison L.; Laine, Muriel; Al Abosy, Rose; Chang, Ya-Fang; Dembo, Anna G.; Schoenfelt, Kelly; Vadhi, Raga; Qiu, Xintao; Rao, Prakash; Santhamma, Bindu; Nair, Hareesh B.; Nickisch, Klaus J.; Long, Henry W.; Becker, Lev; Brown, Myles; Greene, Geoffrey L.

    2018-01-01

    Major roadblocks to developing effective progesterone receptor (PR)-targeted therapies in breast cancer include the lack of highly-specific PR modulators, a poor understanding of the pro- or anti-tumorigenic networks for PR isoforms and ligands, and an incomplete understanding of the cross talk between PR and estrogen receptor (ER) signaling. Through genomic analyses of xenografts treated with various clinically-relevant ER and PR-targeting drugs, we describe how the activation or inhibition of PR differentially reprograms estrogen signaling, resulting in the segregation of transcriptomes into separate PR agonist and antagonist-mediated groups. These findings address an ongoing controversy regarding the clinical utility of PR agonists and antagonists, alone or in combination with tamoxifen, for breast cancer management. Additionally, the two PR isoforms PRA and PRB, bind distinct but overlapping genomic sites and interact with different sets of co-regulators to differentially modulate estrogen signaling to be either pro- or anti-tumorigenic. Of the two isoforms, PRA inhibited gene expression and ER chromatin binding significantly more than PRB. Differential gene expression was observed in PRA and PRB-rich patient tumors and PRA-rich gene signatures had poorer survival outcomes. In support of antiprogestin responsiveness of PRA-rich tumors, gene signatures associated with PR antagonists, but not PR agonists, predicted better survival outcomes. The better patient survival associated with PR antagonists versus PR agonists treatments was further reflected in the higher in vivo anti-tumor activity of therapies that combine tamoxifen with PR antagonists and modulators. This study suggests that distinguishing common effects observed due to concomitant interaction of another receptor with its ligand (agonist or antagonist), from unique isoform and ligand-specific effects will inform the development of biomarkers for patient selection and translation of PR

  20. Determination of the Role of Estrogen Receptors and Estrogen Regulated Genes in B cell Autoreactivity. Addendum

    DTIC Science & Technology

    2012-07-01

    Betty Diamond – DOD FINAL REPORT 9 Figure 3: (A) expression of estrogen receptors ERalpha( Esr1 ) and ERbeta (Esr2) in splenic B cells and (B)Urinary...16 OH-Estradiol metabolite in BALB/c and C57BL6 mice. Esr1 0 0.05 0.1 0.15 0.2 Transit. Mature Transit. Mature Transit. Mature Transit. mature P E2 P

  1. Estrogen rapidly enhances incisional pain of ovariectomized rats primarily through the G protein-coupled estrogen receptor.

    PubMed

    An, Guanghui; Li, Wenhui; Yan, Tao; Li, Shitong

    2014-06-11

    It has become increasingly apparent that the pain threshold of females and males varies in an estrogen dependent manner. To investigate the modulation of pain by estrogen and the molecular mechanisms involved in this process. A total of 48 rats were ovariectomized (OVX). At 14 and 20 days after OVX, rats were divided into eight groups: groups 1-4 were administered drugs intravenously (IV); groups 5-8 were administered through intrathecal (IT) catheter. Hind paw incision was made in all animals to determine incisional pain. Paw withdraw threshold (PWT) was tested prior to and 24 h after incision. The test drugs were applied 24 h after the incision. Rats were either IV or IT administered with: 17-β-estradiol (E2), G protein-coupled estrogen receptor (GPER)-selective agonist (G1), GPER-selective antagonist (G15) and E2 (G15+E2), or solvent. Before and 30 min after IV drug administration and 20 min during the IT catheter administration, PWT was tested and recorded. 24 h after incisional surgery, the PWT of all rats significantly decreased. Both in the IV group and IT group: administration of E2 and G1 significantly decreased PWT. Neither administration of G15+E2 nor solvent significantly changed PWT. Estrogen causes rapid reduction in the mechanical pain threshold of OVX rats via GPER.

  2. The effect of low-dose experimental zearalenone intoxication on the immunoexpression of estrogen receptors in the ovaries of pre-pubertal bitches.

    PubMed

    Gajecka, M

    2012-01-01

    Zearalenone is an estrogenic mycotoxin that often contaminates plant material used in the production of feeds for companion animals. Small daily doses of ingested zearalenone--a competitive substrate modulating the activity of enzymes participating in estrogen biosynthesis at the pre-receptor level--can induce subclinical symptoms of hyperestrogenism in bitches. The objective of this study was to determine the effects of low zearalenone doses on the presence of estrogen receptors in the ovaries of pre-pubertal Beagle bitches. The bitches were divided into three groups of 10 animals each: experimental group I--50 microg zearalenone/kg body weight administered once daily per os; experimental group II--75 microg zearalenone/kg body weight administered once daily per os; control group--placebo containing no ZEN administered per os. The animals were ovariorectomized at the end of the experiment, at 112 days of age. Estrogen receptors were detected in ovarian specimens by immunohistochemical methods. The results revealed an absence of estrogen receptors alpha in all groups. In both experimental groups a decrease in the positive response of estrogen receptors beta in specified structures of ovaries was observed. Very low alpha-zearalenol levels probably attested to the slowing down (hypostimulation) of the biotransformation process. Overall, zearalenone intoxication led to hyperestrogenism during a specific developmental stage of pre-pubertal bitches. As regards hormesis, the threshold dose of zearalenone (adaptive capability) was exceeded in the ovaries of experimental group II animals. The results obtained in both experimental groups suggest that long-term exposure to low-dose zearalenone intoxication decreased the degree of estrogen receptors beta staining in particular structures of ovaries in the experimental bitches, which initiated epigenetic modification mechanisms that inhibited ovarian development.

  3. Transcriptional corepressor SMILE recruits SIRT1 to inhibit nuclear receptor estrogen receptor-related receptor gamma transactivation.

    PubMed

    Xie, Yuan-Bin; Park, Jeong-Hoh; Kim, Don-Kyu; Hwang, Jung Hwan; Oh, Sangmi; Park, Seung Bum; Shong, Minho; Lee, In-Kyu; Choi, Hueng-Sik

    2009-10-16

    SMILE (small heterodimer partner interacting leucine zipper protein) has been identified as a corepressor of the glucocorticoid receptor, constitutive androstane receptor, and hepatocyte nuclear factor 4alpha. Here we show that SMILE also represses estrogen receptor-related receptor gamma (ERRgamma) transactivation. Knockdown of SMILE gene expression increases ERRgamma activity. SMILE directly interacts with ERRgamma in vitro and in vivo. Domain mapping analysis showed that SMILE binds to the AF2 domain of ERRgamma. SMILE represses ERRgamma transactivation partially through competition with coactivators PGC-1alpha, PGC-1beta, and GRIP1. Interestingly, the repression of SMILE on ERRgamma is released by SIRT1 inhibitors, a catalytically inactive SIRT1 mutant, and SIRT1 small interfering RNA but not by histone protein deacetylase inhibitor. In vivo glutathione S-transferase pulldown and coimmunoprecipitation assays validated that SMILE physically interacts with SIRT1. Furthermore, the ERRgamma inverse agonist GSK5182 enhances the interaction of SMILE with ERRgamma and SMILE-mediated repression. Knockdown of SMILE or SIRT1 blocks the repressive effect of GSK5182. Moreover, chromatin immunoprecipitation assays revealed that GSK5182 augments the association of SMILE and SIRT1 on the promoter of the ERRgamma target PDK4. GSK5182 and adenoviral overexpression of SMILE cooperate to repress ERRgamma-induced PDK4 gene expression, and this repression is released by overexpression of a catalytically defective SIRT1 mutant. Finally, we demonstrated that ERRgamma regulates SMILE gene expression, which in turn inhibits ERRgamma. Overall, these findings implicate SMILE as a novel corepressor of ERRgamma and recruitment of SIRT1 as a novel repressive mechanism for SMILE and ERRgamma inverse agonist.

  4. G protein-coupled estrogen receptor 1 (GPER 1) mediates estrogen-induced, proliferation of leiomyoma cells.

    PubMed

    Jiang, Xiuxiu; Ye, Xiaolei; Ma, Junyan; Li, Wen; Wu, Ruijin; Jun, Lin

    2015-01-01

    G protein-coupled estrogen receptor 1 (GPER-1, formerly known as GPR30) has been proposed as the receptor for estrogen-induced, growth of leiomyomas though its precise mechanisms of action are not clear. We obtained leiomyoma cells (LC) and normal smooth muscle cells from 28 women (n = 28, median age 38 years, median parity 1.0). We incubated them with 17-β estradiol (E(2)), after blocking, or upregulating, expression of GPER-1 with ICI182,780 (a GPER-1 agonist) and siGPR30, respectively. We evaluated the role of GPER-1 in the mitogen-activated protein kinase (MAPK) signaling pathway using Western blot analysis. We studied cell proliferation with 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide, and, mitotic activity with phosphohistone H3 (PPH3) expression in leiomyoma, and, matched, normal, smooth muscle tissues using standard immunohistochemistry. Downregulation of GPER-1 expression with siGPR30 partially attenuated the E(2)-activated MAPK signaling pathway (p < 0.01). Upregulation of GPER-1 with ICI182,780 enhanced the E(2)-activated MAPK signaling pathway (p < 0.01). ICI182,780 enhanced E(2)-induced proliferation of LC (p < 0.01), while knock down of the GPER-1 gene with GPER-1 small interfering RNA partially inhibited E(2)-induced cell proliferation (p < 0.01). There were no significant differences in PPH3 expression between LCs and normal smooth muscle tissues (p > 0.05). Neither ICI182,780 nor siGPR30 increased mitosis in LCs (p > 0.05). Our results indicate that GPER-1 mediates proliferation of estrogen-induced, LC by activating the MAPK pathway, and, not by promoting mitosis.

  5. The G protein-coupled estrogen receptor GPER in health and disease

    PubMed Central

    Prossnitz, Eric R.; Barton, Matthias

    2012-01-01

    Estrogens mediate profound effects throughout the body, and regulate physiological and pathological processes in both women and men. The decreased incidence of many diseases in premenopausal women is attributed to the presence of 17β-estradiol, the predominant and most potent endogenous estrogen. In addition to endogenous estrogens, however, several manmade and plant-derived molecules also exhibit estrogenic activity. Traditionally, the actions of 17β-estradiol are ascribed to two nuclear estrogen receptors (ERs), ERα and ERβ, which function as ligand-activated transcription factors. However, 17β-estradiol also mediates rapid signaling events via pathways that involve transmembrane ERs, such as G-protein-coupled ER 1, (GPER, formerly known as GPR30). In the past 10 years, GPER has been implicated in both rapid signaling and transcriptional regulation. With the discovery of GPER-selective ligands that can selectively modulate GPER function in cell experiments and preclinical studies, and the use of GPER-knockout mice, many more potential roles for GPER are currently being elucidated. This Review highlights the physiological roles of GPER in the reproductive, nervous, endocrine, immune and cardiovascular systems, as well as its pathological roles in a diverse array of disorders including cancer. GPER is emerging as a novel therapeutic target and prognostic indicator for these diseases. PMID:21844907

  6. The G-protein-coupled estrogen receptor GPER in health and disease.

    PubMed

    Prossnitz, Eric R; Barton, Matthias

    2011-08-16

    Estrogens mediate profound effects throughout the body and regulate physiological and pathological processes in both women and men. The low prevalence of many diseases in premenopausal women is attributed to the presence of 17β-estradiol, the predominant and most potent endogenous estrogen. In addition to endogenous estrogens, several man-made and plant-derived molecules, such as bisphenol A and genistein, also exhibit estrogenic activity. Traditionally, the actions of 17β-estradiol are ascribed to two nuclear estrogen receptors (ERs), ERα and ERβ, which function as ligand-activated transcription factors. However, 17β-estradiol also mediates rapid signaling events via pathways that involve transmembrane ERs, such as G-protein-coupled ER 1 (GPER; formerly known as GPR30). In the past 10 years, GPER has been implicated in both rapid signaling and transcriptional regulation. With the discovery of GPER-selective ligands that can selectively modulate GPER function in vitro and in preclinical studies and with the use of Gper knockout mice, many more potential roles for GPER are being elucidated. This Review highlights the physiological roles of GPER in the reproductive, nervous, endocrine, immune and cardiovascular systems, as well as its pathological roles in a diverse array of disorders including cancer, for which GPER is emerging as a novel therapeutic target and prognostic indicator.

  7. Synthesis of 3-alkyl naphthalenes as novel estrogen receptor ligands

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fang, Jing; Akwabi-Ameyaw, Adwoa; Britton, Jonathan E.

    2009-06-24

    A series of estrogen receptor ligands based on a 3-alkyl naphthalene scaffold was synthesized using an intramolecular enolate-alkyne cycloaromatization as the key step. Several of these compounds bearing a C6-OH group were shown to be high affinity ligands. All compounds had similar ER{alpha} and ER{beta} binding affinity ranging from micromolar to low nanomolar.

  8. Estrogen Receptor Binding Affinity of Food Contact Material Components Estimated by QSAR.

    PubMed

    Sosnovcová, Jitka; Rucki, Marián; Bendová, Hana

    2016-09-01

    The presented work characterized components of food contact materials (FCM) with potential to bind to estrogen receptor (ER) and cause adverse effects in the human organism. The QSAR Toolbox, software application designed to identify and fill toxicological data gaps for chemical hazard assessment, was used. Estrogen receptors are much less of a lock-and-key interaction than highly specific ones. The ER is nonspecific enough to permit binding with a diverse array of chemical structures. There are three primary ER binding subpockets, each with different requirements for hydrogen bonding. More than 900 compounds approved as of FCM components were evaluated for their potential to bind on ER. All evaluated chemicals were subcategorized to five groups with respect to the binding potential to ER: very strong, strong, moderate, weak binder, and no binder to ER. In total 46 compounds were characterized as potential disturbers of estrogen receptor. Among the group of selected chemicals, compounds with high and even very high affinity to the ER binding subpockets were found. These compounds may act as gene activators and cause adverse effects in the organism, particularly during pregnancy and breast-feeding. It should be considered to carry out further in vitro or in vivo tests to confirm their potential to disturb the regulation of physiological processes in humans by abnormal ER signaling and subsequently remove these chemicals from the list of approved food contact materials. Copyright© by the National Institute of Public Health, Prague 2016

  9. Estrogenic and anti-estrogenic activity of 23 commercial textile dyes.

    PubMed

    Bazin, Ingrid; Ibn Hadj Hassine, Aziza; Haj Hamouda, Yosra; Mnif, Wissem; Bartegi, Ahgleb; Lopez-Ferber, Miguel; De Waard, Michel; Gonzalez, Catherine

    2012-11-01

    The presence of dyes in wastewater effluent of textile industry is well documented. In contrast, the endocrine disrupting effects of these dyes and wastewater effluent have been poorly investigated. Herein, we studied twenty-three commercial dyes, usually used in the textile industry, and extracts of blue jean textile wastewater samples were evaluated for their agonistic and antagonistic estrogen activity. Total estrogenic and anti-estrogenic activities were measured using the Yeast Estrogen Screen bioassay (YES) that evaluates estrogen receptor binding-dependent transcriptional and translational activities. The estrogenic potencies of the dyes and wastewater samples were evaluated by dose-response curves and compared to the dose-response curve of 17β-estradiol (E2), the reference compound. The dose-dependent anti-estrogenic activities of the dyes and wastewater samples were normalized to the known antagonistic effect of 4-hydroxytamoxifen (4-OHT) on the induction of the lac Z reporter gene by E2. About half azo textile dyes have anti-estrogenic activity with the most active being Blue HFRL. Most azo dyes however have no or weak estrogenic activity. E2/dye or E2/waste water ER competitive binding assays show activity of Blue HFRL, benzopurpurine 4B, Everzol Navy Blue FBN, direct red 89 BNL 200% and waste water samples indicating a mechanism of action common to E2. Our results indicate that several textile dyes are potential endocrine disrupting agents. The presence of some of these dyes in textile industry wastewater may thus impact the aquatic ecosystem. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. CERAPP: Collaborative Estrogen Receptor Activity Prediction Project

    PubMed Central

    Mansouri, Kamel; Abdelaziz, Ahmed; Rybacka, Aleksandra; Roncaglioni, Alessandra; Tropsha, Alexander; Varnek, Alexandre; Zakharov, Alexey; Worth, Andrew; Richard, Ann M.; Grulke, Christopher M.; Trisciuzzi, Daniela; Fourches, Denis; Horvath, Dragos; Benfenati, Emilio; Muratov, Eugene; Wedebye, Eva Bay; Grisoni, Francesca; Mangiatordi, Giuseppe F.; Incisivo, Giuseppina M.; Hong, Huixiao; Ng, Hui W.; Tetko, Igor V.; Balabin, Ilya; Kancherla, Jayaram; Shen, Jie; Burton, Julien; Nicklaus, Marc; Cassotti, Matteo; Nikolov, Nikolai G.; Nicolotti, Orazio; Andersson, Patrik L.; Zang, Qingda; Politi, Regina; Beger, Richard D.; Todeschini, Roberto; Huang, Ruili; Farag, Sherif; Rosenberg, Sine A.; Slavov, Svetoslav; Hu, Xin; Judson, Richard S.

    2016-01-01

    Background: Humans are exposed to thousands of man-made chemicals in the environment. Some chemicals mimic natural endocrine hormones and, thus, have the potential to be endocrine disruptors. Most of these chemicals have never been tested for their ability to interact with the estrogen receptor (ER). Risk assessors need tools to prioritize chemicals for evaluation in costly in vivo tests, for instance, within the U.S. EPA Endocrine Disruptor Screening Program. Objectives: We describe a large-scale modeling project called CERAPP (Collaborative Estrogen Receptor Activity Prediction Project) and demonstrate the efficacy of using predictive computational models trained on high-throughput screening data to evaluate thousands of chemicals for ER-related activity and prioritize them for further testing. Methods: CERAPP combined multiple models developed in collaboration with 17 groups in the United States and Europe to predict ER activity of a common set of 32,464 chemical structures. Quantitative structure–activity relationship models and docking approaches were employed, mostly using a common training set of 1,677 chemical structures provided by the U.S. EPA, to build a total of 40 categorical and 8 continuous models for binding, agonist, and antagonist ER activity. All predictions were evaluated on a set of 7,522 chemicals curated from the literature. To overcome the limitations of single models, a consensus was built by weighting models on scores based on their evaluated accuracies. Results: Individual model scores ranged from 0.69 to 0.85, showing high prediction reliabilities. Out of the 32,464 chemicals, the consensus model predicted 4,001 chemicals (12.3%) as high priority actives and 6,742 potential actives (20.8%) to be considered for further testing. Conclusion: This project demonstrated the possibility to screen large libraries of chemicals using a consensus of different in silico approaches. This concept will be applied in future projects related to other

  11. A new series of estrogen receptor modulators that display selectivity for estrogen receptor beta.

    PubMed

    Henke, Brad R; Consler, Thomas G; Go, Ning; Hale, Ron L; Hohman, Dana R; Jones, Stacey A; Lu, Amy T; Moore, Linda B; Moore, John T; Orband-Miller, Lisa A; Robinett, R Graham; Shearin, Jean; Spearing, Paul K; Stewart, Eugene L; Turnbull, Philip S; Weaver, Susan L; Williams, Shawn P; Wisely, G Bruce; Lambert, Millard H

    2002-12-05

    A series of 1,3,5-triazine-based estrogen receptor (ER) modulators that are modestly selective for the ERbeta subtype are reported. Compound 1, which displayed modest potency and selectivity for ERbeta vs ERalpha, was identified via high-throughput screening utilizing an ERbeta SPA-based binding assay. Subsequent analogue preparation resulted in the identification of compounds such as 21 and 43 that display 25- to 30-fold selectivity for ERbeta with potencies in the 10-30 nM range. These compounds profile as full antagonists at ERbeta and weak partial agonists at ERalpha in a cell-based reporter gene assay. In addition, the X-ray crystal structure of compound 15 complexed with the ligand binding domain of ERbeta has been solved and was utilized in the design of more conformationally restrained analogues such as 31 in an attempt to increase selectivity for the ERbeta subtype.

  12. The human estrogen receptor can regulate exogenous but not endogenous vitellogenin gene promoters in a Xenopus cell line

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Seiler-Tuyns, A.; Merillat, A.M.; Haefliger, D.N.

    Transfection of a human estrogen receptor cDNA expression vector (HEO) into cultured Xenopus kidney cells confers estrogen responsiveness to the recipient cells as demonstrated by the hormone dependent expression of co-transfected Xenopus vitellogenin-CAT chimeric genes. The estrogen stimulation of these vit-CAT genes is dependent upon the presence of the vitellogenin estrogen responsive element (ERE) in their 5{prime} flanking region. Thus, functional human estrogen receptor (hER) can be synthesized in heterologous lower vertebrate cells and can act as a trans-acting regulatory factor that is necessary, together with estradiol, for the induction of the vit-CAT constructs in these cells. In addition, vitellogeninmore » minigenes co-transfected with the HEO expression vector also respond to hormonal stimulation. Their induction is not higher than that of the vit-CAT chimeric genes. It suggests that in the Xenopus kidney cell line B 3.2, the structural parts of the vitellogenin minigenes do not play a role in the induction process. Furthermore, no stabilizing effect of estrogen on vitellogenin mRNA is observed in these cells.« less

  13. Sexually dimorphic role of G protein-coupled estrogen receptor (GPER) in modulating energy homeostasis.

    PubMed

    Davis, Kathryn E; Carstens, Elizabeth J; Irani, Boman G; Gent, Lana M; Hahner, Lisa M; Clegg, Deborah J

    2014-06-01

    This article is part of a Special Issue "Energy Balance". The classical estrogen receptors, estrogen receptor-α and estrogen receptor-β are well established in the regulation of body weight and energy homeostasis in both male and female mice, whereas, the role for G protein-coupled estrogen receptor 1 (GPER) as a modulator of energy homeostasis remains controversial. This study sought to determine whether gene deletion of GPER (GPER KO) alters body weight, body adiposity, food intake, and energy homeostasis in both males and females. Male mice lacking GPER developed moderate obesity and larger adipocyte size beginning at 8 weeks of age, with significant reductions in energy expenditure, but not food intake or adipocyte number. Female GPER KO mice developed increased body weight relative to WT females a full 6 weeks later than the male GPER KO mice. Female GPER KO mice also had reductions in energy expenditure, but no significant increases in body fat content. Consistent with their decrease in energy expenditure, GPER KO males and females showed significant reductions in two brown fat thermogenic proteins. GPER KO females, prior to their divergence in body weight, were less sensitive than WT females to the feeding-inhibitory effects of leptin and CCK. Additionally, body weight was not as modulated by ovariectomy or estradiol replacement in GPER KO mice. Estradiol treatment activated phosphorylated extracellular signal-regulated kinase (pERK) in WT but not GPER KO females. For the first time, GPER expression was found in the adipocyte but not the stromal fraction of adipose tissue. Together, these results provide new information elucidating a sexual dimorphism in GPER function in the development of postpubertal energy balance. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Liganded and unliganded activation of estrogen receptor and hormone replacement therapies

    PubMed Central

    Maggi, Adriana

    2011-01-01

    Over the past two decades, our understanding of estrogen receptor physiology in mammals widened considerably as we acquired a deeper appreciation of the roles of estrogen receptor alpha and beta (ERα and ERβ) in reproduction as well as in bone and metabolic homeostasis, depression, vascular disorders, neurodegenerative diseases and cancer. In addition, our insights on ER transcriptional functions in cells increased considerably with the demonstration that ER activity is not strictly dependent on ligand availability. Indeed, unliganded ERs may be transcriptionally active and post-translational modifications play a major role in this context. The finding that several intracellular transduction molecules may regulate ER transcriptional programs indicates that ERs may act as a hub where several molecular pathways converge: this allows to maintain ER transcriptional activity in tune with all cell functions. Likely, the biological relevant role of ER was favored by evolution as a mean of integration between reproductive and metabolic functions. We here review the post-translational modifications modulating ER transcriptional activity in the presence or in the absence of estrogens and underline their potential role for ER tissue-specific activities. In our opinion, a better comprehension of the variety of molecular events that control ER activity in reproductive and non-reproductive organs is the foundation for the design of safer and more efficacious hormone-based therapies, particularly for menopause. PMID:21605666

  15. G-Protein-Coupled Estrogen Receptor Antagonist G15 Decreases Estrogen-Induced Development of Non-Small Cell Lung Cancer.

    PubMed

    Liu, Changyu; Liao, Yongde; Fan, Sheng; Fu, Xiangning; Xiong, Jing; Zhou, Sheng; Zou, Man; Wang, Jianmiao

    2017-08-25

    G-protein-coupled estrogen receptor (GPER) was found to promote Non-small cell lung cancer (NSCLC) by estrogen, indicating the potential necessity of inhibiting GPER by selective antagonist. This study was performed to elucidate the function of GPER selective inhibitor G15 in NSCLC development. Cytoplasmic GPER (cGPER) and nuclear GPER (nGPER) were detected by immunohistochemical analysis in NSCLC samples. The relation of GPER and estrogen receptor β (ERβ) expression and correlation between GPER, ERβ and clinical factors were analyzed. The effects of activating GPER and function of G15 were analyzed in proliferation of A549, H1793 cell lines and development of urethane-induced adenocarcinoma. Overexpression of cGPER and nGPER was detected in 80.49% (120/150) and 52.00% (78/150) of the NSCLC samples. High expression of GPER related with higher stages, poorer differentiation and high expression of ERβ. Protein level of GPER in A549 and H1793 cell lines increased by treatment of E2, G1 (GPER agonist) or Ful (fulvestrant, ERβ antagonist), and decreased by G15. Administration with G15 reversed the E2- or G1-induced cell growth by inhibiting GPER. In urethane-induced adenocarcinoma mice, number of tumor nodules and tumor index increased in E2 or G1 group and decreased by treatment of G15. These findings deomonstrate that using of G15 to block GPER signaling may be considered as a new therapeutic target in NSCLC.

  16. Dopamine activates masculine sexual behavior independent of the estrogen receptor alpha.

    PubMed

    Wersinger, S R; Rissman, E F

    2000-06-01

    Estrogen receptor alpha (ERalpha) is believed to be a critical part of the regulatory processes involved in normal reproduction and sexual behavior. However, in this study we show the ERalpha is not required for display of masculine sexual behavior. Male and female, ERalpha knock-out (ERalphaKO) and wild-type mice were gonadectomized and implanted with testosterone. Sexual behavior and social preferences were tested after injection of the dopamine agonist, apomorphine (APO), or vehicle. All wild-type mice showed normal masculine behavior, including mounts and pelvic thrusts in females, and ejaculation in males. In agreement with past reports, ERalphaKO mice, given vehicle, failed to show mating behavior. Yet, ERalphaKO males given APO showed masculine copulatory behavior and chemoinvestigatory behavior directed at females. ERalphaKO females, treated with APO, mounted and thrusted when tested with receptive females. HPLC revealed that wild-type and ERalphaKO mice had equivalent catecholamine content in brain regions associated with masculine sexual behavior. These data show that the ERalpha is not essential during development or adulthood for the expression of masculine sexual behavior in mice. Moreover, dopamine can activate sexual behavior via a mechanism that either acts on an ER other than ERalpha or via an estrogen-independent pathway.

  17. Bisphenol A and Related Alkylphenols Exert Nongenomic Estrogenic Actions Through a G Protein-Coupled Estrogen Receptor 1 (Gper)/Epidermal Growth Factor Receptor (Egfr) Pathway to Inhibit Meiotic Maturation of Zebrafish Oocytes.

    PubMed

    Fitzgerald, Amanda C; Peyton, Candace; Dong, Jing; Thomas, Peter

    2015-12-01

    Xenobiotic estrogens, such as bisphenol A (BPA), disrupt a wide variety of genomic estrogen actions, but their nongenomic estrogen actions remain poorly understood. We investigated nongenomic estrogenic effects of low concentrations of BPA and three related alkylphenols on the inhibition of zebrafish oocye maturation (OM) mediated through a G protein-coupled estrogen receptor 1 (Gper)-dependent epidermal growth factor receptor (Egfr) pathway. BPA (10-100 nM) treatment for 3 h mimicked the effects of estradiol-17beta (E2) and EGF, decreasing spontaneous maturation of defolliculated zebrafish oocytes, an effect not blocked by coincubation with actinomycin D, but blocked by coincubation with a Gper antibody. BPA displayed relatively high binding affinity (15.8% that of E2) for recombinant zebrafish Gper. The inhibitory effects of BPA were attenuated by inhibition of upstream regulators of Egfr, intracellular tyrosine kinase (Src) with PP2, and matrix metalloproteinase with ilomastat. Treatment with an inhibitor of Egfr transactivation, AG1478, and an inhibitor of the mitogen-activated protein kinase (MAPK) 3/1 pathway, U0126, increased spontaneous OM and blocked the inhibitory effects of BPA, E2, and the selective GPER agonist, G-1. Western blot analysis showed that BPA (10-200 nM) mimicked the stimulatory effects of E2 and EGF on Mapk3/1 phosphorylation. Tetrabromobisphenol A, 4-nonylphenol, and tetrachlorobisphenol A (5-100 nM) also inhibited OM, an effect blocked by cotreatment with AG1478, as well as with the GPER antagonist, G-15, and displayed similar binding affinities as BPA to zebrafish Gper. The results suggest that BPA and related alkylphenols disrupt zebrafish OM by a novel nongenomic estrogenic mechanism involving activation of the Gper/Egfr/Mapk3/1 pathway. © 2015 by the Society for the Study of Reproduction, Inc.

  18. Estrogen-Related Receptor α (ERRα) and ERRγ Are Essential Coordinators of Cardiac Metabolism and Function

    PubMed Central

    Wang, Ting; McDonald, Caitlin; Petrenko, Nataliya B.; Leblanc, Mathias; Wang, Tao; Giguere, Vincent; Evans, Ronald M.; Patel, Vickas V.

    2015-01-01

    Almost all cellular functions are powered by a continuous energy supply derived from cellular metabolism. However, it is little understood how cellular energy production is coordinated with diverse energy-consuming cellular functions. Here, using the cardiac muscle system, we demonstrate that nuclear receptors estrogen-related receptor α (ERRα) and ERRγ are essential transcriptional coordinators of cardiac energy production and consumption. On the one hand, ERRα and ERRγ together are vital for intact cardiomyocyte metabolism by directly controlling expression of genes important for mitochondrial functions and dynamics. On the other hand, ERRα and ERRγ influence major cardiomyocyte energy consumption functions through direct transcriptional regulation of key contraction, calcium homeostasis, and conduction genes. Mice lacking both ERRα and cardiac ERRγ develop severe bradycardia, lethal cardiomyopathy, and heart failure featuring metabolic, contractile, and conduction dysfunctions. These results illustrate that the ERR transcriptional pathway is essential to couple cellular energy metabolism with energy consumption processes in order to maintain normal cardiac function. PMID:25624346

  19. Differential regulation of the human progesterone receptor gene through an estrogen response element half site and Sp1 sites.

    PubMed

    Petz, Larry N; Ziegler, Yvonne S; Schultz, Jennifer R; Kim, Hwajin; Kemper, J Kim; Nardulli, Ann M

    2004-02-01

    The progesterone receptor (PR) gene is regulated by estrogen in normal reproductive tissues and in MCF-7 human breast cancer cells. Although it is generally thought that estrogen responsiveness is mediated by interaction of the ligand-occupied estrogen receptor (ER) with estrogen response elements (EREs) in target genes, the human progesterone receptor (PR) gene lacks a palindromic ERE. Promoter A of the PR gene does, however, contain an ERE half site upstream of two adjacent Sp1 sites from +571 to +595, the +571 ERE/Sp1 site. We have examined the individual contributions of the ERE half site and the two Sp1 sites in regulating estrogen responsiveness. Transient transfection assays demonstrated that both Sp1 sites were critical for estrogen-mediated activation of the PR gene. Interestingly, rather than decreasing transcription, mutations in the ERE half site increased transcription substantially suggesting that this site plays a role in limiting transcription. Chromatin immunoprecipitation assays demonstrated that Sp1 was associated with the +571 ERE/Sp1 site in the endogenous PR gene in the absence and in the presence of estrogen, but that ERalpha was only associated with this region of the PR gene after MCF-7 cells had been treated with estrogen. Our studies provide evidence that effective regulation of transcription through the +571 ERE/Sp1 site requires the binding of ERalpha and Sp1 to their respective cis elements and the appropriate interaction of ERalpha and Sp1 with other coregulatory proteins and transcription factors.

  20. Design and Synthesis of Selective Estrogen Receptor beta Agonists and Their Pharmacology

    NASA Astrophysics Data System (ADS)

    Perera, K. L. Iresha Sampathi

    Estrogens (17beta-estradiol, E2) have garnered considerable attention in influencing cognitive process in relation to phases of the menstrual cycle, aging and menopausal symptoms. However, hormone replacement therapy can have deleterious effects leading to breast and endometrial cancer, predominantly mediated by estrogen receptor-alpha (ERalpha) the major isoform present in the mammary gland and uterus. Further evidence supports a dominant role of estrogen receptor-beta (ERbeta) for improved cognitive effects such as enhanced hippocampal signaling and memory consolidation via estrogen activated signaling cascades. Creation of the ERbeta selective ligands is challenging due to high structural similarity of both receptors. Thus far, several ERbeta selective agonists have been developed, however, none of these have made it to clinical use due to their lower selectivity or considerable side effects. The research in this dissertation involved the design of non-steroidal ERbeta selective agonists for hippocampal memory consolidation. The step-wise process to achieve the ultimate goal of this research includes: (1) design and synthesis of (4-hydroxyphenyl)cyclohexyl or cycloheptyl derivatives, (2) in vitro biological evaluation of synthesized compounds to identify highly potent and selective candidates, and (3) in vivo biological evaluation of selected candidates for hippocampal memory consolidation. Several (4-hydroxyphenyl)cyclohexyl or cycloheptyl derivatives were synthesized having structural alterations on both aromatic and cyclohexyl/heptyl ring scaffolds. ERbeta agonist potency was initially evaluated in TR-FRET ERbeta ligand binding assay and compounds having high potency were re-evaluated in functional cell based assays for potency and ERbeta vs. ERalpha selectivity. Two compounds from each series, ISP 163-PK4 and ISP 358-2 were identified as most selective ERbeta agonists. Both compounds revealed high metabolic stability, solubility and no cross reactivity

  1. Bile Acid Receptor Agonist GW4064 Regulates PPARγ Coactivator-1α Expression Through Estrogen Receptor-Related Receptor α

    PubMed Central

    Dwivedi, Shailendra Kumar Dhar; Singh, Nidhi; Kumari, Rashmi; Mishra, Jay Sharan; Tripathi, Sarita; Banerjee, Priyam; Shah, Priyanka; Kukshal, Vandana; Tyagi, Abdul Malik; Gaikwad, Anil Nilkanth; Chaturvedi, Rajnish Kumar; Mishra, Durga Prasad; Trivedi, Arun Kumar; Sanyal, Somali; Chattopadhyay, Naibedya; Ramachandran, Ravishankar; Siddiqi, Mohammad Imran; Bandyopadhyay, Arun; Arora, Ashish; Lundåsen, Thomas; Anakk, Sayee Priyadarshini; Moore, David D.

    2011-01-01

    Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) is induced in energy-starved conditions and is a key regulator of energy homeostasis. This makes PGC-1α an attractive therapeutic target for metabolic syndrome and diabetes. In our effort to identify new regulators of PGC-1α expression, we found that GW4064, a widely used synthetic agonist for the nuclear bile acid receptor [farnesoid X receptor (FXR)] strongly enhances PGC-1α promoter reporter activity, mRNA, and protein expression. This induction in PGC-1α concomitantly enhances mitochondrial mass and expression of several PGC-1α target genes involved in mitochondrial function. Using FXR-rich or FXR-nonexpressing cell lines and tissues, we found that this effect of GW4064 is not mediated directly by FXR but occurs via activation of estrogen receptor-related receptor α (ERRα). Cell-based, biochemical and biophysical assays indicate GW4064 as an agonist of ERR proteins. Interestingly, FXR disruption alters GW4064 induction of PGC-1α mRNA in a tissue-dependent manner. Using FXR-null [FXR knockout (FXRKO)] mice, we determined that GW4064 induction of PGC-1α expression is not affected in oxidative soleus muscles of FXRKO mice but is compromised in the FXRKO liver. Mechanistic studies to explain these differences revealed that FXR physically interacts with ERR and protects them from repression by the atypical corepressor, small heterodimer partner in liver. Together, this interplay between ERRα-FXR-PGC-1α and small heterodimer partner offers new insights into the biological functions of ERRα and FXR, thus providing a knowledge base for therapeutics in energy balance-related pathophysiology. PMID:21493670

  2. Estrogen receptor β and Liver X receptor β: biology and therapeutic potential in CNS diseases.

    PubMed

    Warner, M; Gustafsson, J-A

    2015-02-01

    In the last decade of the twentieth century, two nuclear receptors were discovered in our laboratory and, very surprisingly, were found to have key roles in the central nervous system. These receptors have provided some novel insights into the etiology and progression of neurodegenerative diseases and anxiety disorders. The two receptors are estrogen receptor beta (ERβ) and liver X receptor beta (LXRβ). Both ERβ and LXRβ have potent anti-inflammatory activities and, in addition, LXRβ is involved in the genesis of dopaminergic neurons during development and protection of these neurons against neurodegeneration in adult life. ERβ is involved in migration of cortical neurons and calretinin-positive GABAergic interneurons during development and maintenance of serotonergic neurons in adults. Both receptors are present in magnocellular neurons of the hypothalamic preoptic area including those expressing vasopressin and oxytocin. As both ERβ and LXRβ are ligand-activated transcription factors, their ligands hold great potential in the treatment of diseases of the CNS.

  3. Estrogen receptor mRNA expression patterns in the liver and ovary of female rainbow trout over a complete reproductive cycle

    PubMed Central

    Nagler, James J.; Cavileer, Timothy D.; Verducci, Joseph S.; Schultz, Irvin R.; Hook, Sharon E.; Hayton, William L.

    2012-01-01

    Estrogens are critical hormones involved in reproduction and need to bind to estrogen receptors in target organs for biological activity. Fishes have two distinct estrogen receptor subtypes, alpha (α) and beta (β), with variable combinations of additional isoforms of each subtype dependent on the history of genome duplication within a taxon. The comparative expression patterns of estrogen receptor isoforms during the female reproductive cycle will provide important insights into the unique function and importance of each. The purpose of this study was to measure the mRNAs for the four estrogen receptor isoforms (erα1, erα2, erβ1, erβ2) in the liver and ovary of adult, female rainbow trout over the course of an annual reproductive cycle. The expression of estrogen receptor mRNA isoforms was measured by quantitative real-time RT-PCR. Several reproductive indices (gonadosomatic index, maximum oocyte diameter, plasma estradiol-17β, plasma vitellogenin, and ovulation) were also quantified for comparison and used in a correlation analysis to examine any inter-relationships. Of the four isoforms, the expression of erα1 was highest in the liver, and had a significant positive correlation with liver erβ1 expression. Liver expression of erα2 mRNA was the lowest, but showed a significant positive correlation with maximum oocyte diameter in the ovary. The pattern of the erβ isoforms in liver was one of initially elevated mRNA expression followed by a gradual decrease as reproductive development proceeded. In the ovary the erβ1 isoform had the highest mRNA expression of all estrogen receptor isoforms, at the beginning of the reproductive cycle, but then decreased afterward. Both ovarian erβ isoforms had a significant positive correlation with one another. In contrast, erα2 mRNA expression showed a high maximum level in the ovary near the end of the cycle along with a significant positive correlation with plasma estradiol-17β levels; the highest gonadosomatic

  4. GPER-1/GPR30 a novel estrogen receptor sited in the cell membrane: therapeutic coupling to breast cancer.

    PubMed

    Molina, Luis; Figueroa, Carlos D; Bhoola, Kanti D; Ehrenfeld, Pamela

    2017-08-01

    Breast cancer is clinically classified as 'estrogen-positive' when at least 1% of cancer cells stain for the estrogen receptor alpha (ERα). However, recent research on both basic and clinical aspects of breast cancer suggests that GPER-1 (G protein-coupled estrogen receptor-1) may have an important role in breast cancer. Areas covered: This review provides a comprehensive and systematic literature search on GPER-1. We have focused on the role of GPER-1 in breast cancer and on resistance to endocrine therapy, an unsolved clinical issue still under discussion. Expert opinion: The discovery of GPER-1 as a novel estrogen receptor is unique and the signaling pathways activated by its stimulation, when compared to the classical nuclear ERα, indicate a potential role of GPER-1 in the genesis and mechanisms of drug resistance in breast cancer. Tumors expressing ERα represent the largest group of breast cancer patients indicating that more women eventually die from ERα-positive breast tumors than from other more malignant breast cancer subtypes such as HER2-positive and the triple negative groups. It is important to develop new strategies on endocrine therapy with regard to ERα and GPER-1 receptors to achieve innovative successful therapeutic tools.

  5. Expression of Genomic Functional Estrogen Receptor 1 in Mouse Sertoli Cells

    PubMed Central

    Lin, Jing; Zhu, Jia; Li, Xian; Li, Shengqiang; Lan, Zijian; Ko, Jay

    2014-01-01

    There is no consensus whether Sertoli cells express estrogen receptor 1 (Esr1). Reverse transcription-polymerase chain reaction, Western blot, and immunofluorescence demonstrated that mouse Sertoli cell lines, TM4, MSC-1, and 15P-1, and purified primary mouse Sertoli cells (PSCs) contained Esr1 messenger RNA and proteins. Incubation of Sertoli cells with 17β-estradiol (E2) or ESR1 agonist stimulated the expression of an estrogen responsive gene Greb1, which was prevented by ESR inhibitor or ESR1 antagonist. Overexpression of Esr1 in MSC-1 enhanced E2-induced Greb1 expression, while knockdown of Esr1 by small interfering RNA in TM4 attenuated the response. Furthermore, E2-induced Greb1 expression was abolished in the PSCs isolated from Amh-Cre/Esr1-floxed mice in which Esr1 in Sertoli cells were selectively deleted. Chromatin immunoprecipitation assays indicated that E2-induced Greb1 expression in Sertoli cells was mediated by binding of ESR1 to estrogen responsive elements. In summary, ligand-dependent nuclear ESR1 was present in mouse Sertoli cells and mediates a classical genomic action of estrogens. PMID:24615934

  6. Histone H2A.Z is essential for estrogen receptor signaling

    PubMed Central

    Gévry, Nicolas; Hardy, Sara; Jacques, Pierre-Étienne; Laflamme, Liette; Svotelis, Amy; Robert, François; Gaudreau, Luc

    2009-01-01

    Incorporation of H2A.Z into the chromatin of inactive promoters has been shown to poise genes for their expression. Here we provide strong evidence that H2A.Z is incorporated into the promoter regions of estrogen receptor (ERα) target genes only upon gene induction, and that, in a cyclic pattern. Moreover, members of the human H2A.Z-depositing complex, p400, also follow the same gene recruitment kinetics as H2A.Z. Importantly, cellular depletion of H2A.Z or p400 leads to a severe defect in estrogen signaling, including loss of estrogen-specific cell proliferation. We find that incorporation of H2A.Z within TFF1 promoter chromatin allows nucleosomes to adopt preferential positions along the DNA translational axis. Finally, we provide evidence that H2A.Z is essential to allow estrogen-responsive enhancer function. Taken together, our results provide strong mechanistic insight into how H2A.Z regulates ERα-mediated gene expression and provide a novel link between H2A.Z–p400 and ERα-dependent gene regulation and enhancer function. PMID:19515975

  7. Nuclear receptor co-regulator Kruppel-like factor 9 and prohibitin 2 expression in estrogen-induced epithelial cell proliferation in the mouse uterus

    USDA-ARS?s Scientific Manuscript database

    Estrogen, acting through its cognate receptor estrogen receptor-' (ESR1), is a critical regulator of uterine endometrial epithelial proliferation. Although the dynamic communication between endometrial stromal (ST) and epithelial cells is considered to be an important component in this process, key ...

  8. 17β-Estradiol and/or estrogen receptor alpha signaling blocks protein phosphatase 1 mediated ISO induced cardiac hypertrophy.

    PubMed

    Fang, Hsin-Yuan; Hung, Meng-Yu; Lin, Yueh-Min; Pandey, Sudhir; Chang, Chia-Chien; Lin, Kuan-Ho; Shen, Chia-Yao; Viswanadha, Vijaya Padma; Kuo, Wei-Wen; Huang, Chih-Yang

    2018-01-01

    Earlier studies have shown that estrogen possess protective function against the development of pathological cardiac hypertrophy. However, the molecular mechanisms of estrogens (E2) protective effect are poorly understood. Additionally, abnormal activation of β-adrenergic signaling have been implicated in the development of pathological cardiac remodeling. However, the role of serine/threonine protein phosphatase 1 (PP1) in pathological cardiac remodeling under the influence of β-adrenergic signaling have been sparsely investigated. In this study, we assessed the downstream effects of abnormal activation of PP1 upon isoproterenol (ISO) induced pathological cardiac changes. We found that pre-treatment of 17β-estradiol (E2), tet-on estrogen receptor-α, or both significantly inhibited ISO-induced increase in cell size, hypertrophy marker gene expression and cytosolic calcium accumulation in H9c2 cells. Additionally, treatment with estrogen receptor inhibitor (ICI) reversed those effects, implicating role of E2 in inhibiting pathological cardiac remodeling. However, specific inhibition of ERα using melatonin, reduced ISO-induced PP1c expression and enhanced the level of ser-16 phosphorylated phospholamban (PLB), responsible for regulation of sarcoplasmic reticulum Ca2+-ATPase (SERCA) activity. Furthermore, hypertrophic effect caused by overexpression of PP1cα was reduced by treatment with specific inhibitor of ERα. Collectively, we found that estrogen and estrogen receptor-α have protective effect against pathological cardiac changes by suppressing PP1 expression and its downstream signaling pathway, which further needs to be elucidated.

  9. Unliganded estrogen receptor α stimulates bone sialoprotein gene expression.

    PubMed

    Takai, Hideki; Matsumura, Hiroyoshi; Matsui, Sari; Kim, Kyung Mi; Mezawa, Masaru; Nakayama, Yohei; Ogata, Yorimasa

    2014-04-10

    Estrogen is one of the steroid hormones essential for skeletal development. The estrogen receptor (ER) is a transcription factor and a member of the steroid receptor superfamily. There are two different forms of the ER, usually referred to as α and β, each encoded by a separate gene. Hormone-activated ERs form dimers, since the two forms are coexpressed in many cell types. Bone sialoprotein (BSP) is a tissue-specific acidic glycoprotein that is expressed by differentiated osteoblasts, odontoblasts and cementoblasts during the initial formation of mineralized tissue. To determine the molecular basis of the tissue-specific expression of BSP and its regulation by estrogen and the ER, we have analyzed the effects of β-estradiol and ERα on BSP gene transcription. ERα protein levels were increased after ERα overexpression in ROS17/2.8 cells. While BSP mRNA levels were increased by ERα overexpression, the endogenous and overexpressed BSP mRNA levels were not changed by β-estradiol (10(-8)M, 24 h). Luciferase activities of different sized BSP promoter constructs (pLUC3~6) were increased by ERα overexpression, whereas basal and induced luciferase activities by ERα overexpression were not influenced by β-estradiol. Effects of ERα overexpression were abrogated by 2 bp mutations in either the cAMP response element (CRE) or activator protein 1 (AP1)/glucocorticoid response element (GRE). Gel shift analyses showed that ERα overexpression increased binding to the CRE and AP1/GRE elements. Notably, the CRE-protein complexes were disrupted by ERα, CREB and phospho-CREB antibodies. The AP1/GRE-protein complexes were supershifted by the c-Fos antibody. These studies demonstrate that ERα stimulates BSP gene transcription in a ligand-independent manner by targeting the CRE and AP1/GRE elements in the rat BSP gene promoter. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Synergism between a half-site and an imperfect estrogen-responsive element, and cooperation with COUP-TFI are required for estrogen receptor (ER) to achieve a maximal estrogen-stimulation of rainbow trout ER gene.

    PubMed

    Petit, F G; Métivier, R; Valotaire, Y; Pakdel, F

    1999-01-01

    In all oviparous, liver represents one of the main E2-target tissues where estrogen receptor (ER) constitutes the key mediator of estrogen action. The rainbow trout estrogen receptor (rtER) gene expression is markedly up-regulated by estrogens and the sequences responsible for this autoregulation have been located in a 0.2 kb upstream transcription start site within - 40/- 248 enhancer region. Absence of interference with steroid hormone receptors and tissue-specific factors and a conserved basal transcriptional machinery between yeast and higher eukaryotes, make yeast a simple assay system that will enable determination of important cis-acting regulatory sequences within rtER gene promoter and identification of transcription factors implicated in the regulation of this gene. Deletion analysis allowed to show a synergistic effect between an imperfect estrogen-responsive element (ERE) and a consensus half-ERE to achieve a high hormone-dependent transcriptional activation of the rtER gene promoter in the presence of stably expressed rtER. As in mammalian cells, here we observed a positive regulation of the rtER gene promoter by the chicken ovalbumin upstream promoter-transcription factor I (COUP-TFI) through enhancing autoregulation. Using a point mutation COUP-TFI mutant unable to bind DNA demonstrates that enhancement of rtER gene autoregulation requires the interaction of COUP-TFI to the DNA. Moreover, this enhancement of transcriptional activation by COUP-TFI requires specifically the AF-1 transactivation function of ER and can be observed in the presence of E2 or 4-hydroxytamoxifen but not ICI 164384. Thus, this paper describes the reconstitution of a hormone-responsive transcription unit in yeast in which the regulation of rtER gene promoter could be enhanced by the participation of cis-elements and/or trans-acting factors, such as ER itself or COUP-TF.

  11. A Suppressive Antagonism Evidences Progesterone and Estrogen Receptor Pathway Interaction with Concomitant Regulation of Hand2, Bmp2 and ERK during Early Decidualization

    PubMed Central

    Mestre-Citrinovitz, Ana C.; Kleff, Veronika; Vallejo, Griselda

    2015-01-01

    Progesterone receptor and estrogen receptor participate in growth and differentiation of the different rat decidual regions. Steroid hormone receptor antagonists were used to study steroid regulation of decidualization. Here we describe a suppressive interaction between progesterone receptor (onapristone) and estrogen receptor (ICI182780) antagonists and their relation to a rescue phenomenon with concomitant regulation of Hand2, Bmp2 and p-ERK1/2 during the early decidualization steps. Phenotypes of decidua development produced by antagonist treatments were characterized by morphology, proliferation, differentiation, angiogenesis and expression of signaling molecules. We found that suppression of progesterone receptor activity by onapristone treatment resulted in resorption of the implantation sites with concomitant decrease in progesterone and estrogen receptors, PCNA, KI67 antigen, DESMIN, CCND3, CX43, Prl8a2, and signaling players such as transcription factor Hand2, Bmp2 mRNAs and p-ERK1/2. Moreover, FGF-2 and Vegfa increased as a consequence of onapristone treatment. Implantation sites from antagonist of estrogen receptor treated rats developed all decidual regions, but showed an anomalous blood vessel formation at the mesometrial part of the decidua. The deleterious effect of onapristone was partially counteracted by the impairment of estrogen receptor activity with rescue of expression levels of hormone steroid receptors, proliferation and differentiation markers, and the induction of a probably compensatory increase in signaling molecules Hand2, Bmp2 and ERK1/2 activation compared to oil treated controls. This novel drug interaction during decidualization could be applied to pathological endometrial cell proliferation processes to improve therapies using steroid hormone receptor targets. PMID:25897495

  12. Investigations of new lead structures for the design of selective estrogen receptor modulators.

    PubMed

    Gust, R; Keilitz, R; Schmidt, K

    2001-06-07

    Heterocyclic derivatives of (R,S)/(S,R)-1-(2-chloro-4-hydroxyphenyl)-2-(2,6-dichloro-4-hydroxyphenyl)ethylenediamine (L1) were synthesized and tested for estrogen receptor binding. The selection of the heterocycles was based on theoretical consideration. (2R,3S)/(2S,3R)-2-(2-Chloro-4-hydroxyphenyl)-3-(2,6-dichloro-4-hydroxyphenyl)piperazine 2, (4R,5S)/(4S,5R)-4-(2-chloro-4-hydroxyphenyl)-5-(2,6-dichloro-4-hydroxyphenyl)-2-imidazoline 3, and 4-(2-chloro-4-hydroxyphenyl)-5-(2,6-dichloro-4-hydroxyphenyl)imidazole 4 possess a spatial structure with neighboring aromatic rings as is realized in hormonally active [1,2-diphenylethylenediamine]platinum(II) complexes. The 1,2-diphenylethane pharmacophor, however, cannot adapt an antiperiplanar conformation to interact with the estrogen receptor (ER) comparable to synthetic (e.g., diethylstilbestrol (DES)) or steroidal (e.g., estradiol (E2)) estrogens. Due to the different spatial structures, the heterocycles cause only a marginal displacement of E2 from its binding site (relative binding affinity (RBA) < 0.1%). Nevertheless, unequivocally ER mediated gene activation was verified on the MCF-7-2a cell line. Imidazoline 3 as the most active compound reached the maximum effect of E2 (100% activation) in a concentration of 5 x 10(-7) M, while piperazine 2 and imidazole 4 activate luciferase expression only in a small but significant amount of 20% and 27%, respectively. We therefore assigned these heterocyclic compounds to a second class of hormones (type-II-estrogens), which are attached at the ER at different amino acids than DES or E2 (type-I-estrogens).

  13. Estrogen receptors regulate the estrous behavior induced by progestins, peptides, and prostaglandin E2.

    PubMed

    Lima-Hernández, F J; Gómora-Arrati, P; García-Juárez, M; Blaustein, J D; Etgen, A M; Beyer, C; González-Flores, O

    2014-07-01

    The role of classical estrogen receptors (ERs) in priming female reproductive behavior has been studied previously; however, the participation of this receptor during activation of estrous behavior has not been extensively studied. The purpose of this work was to test the possibility that the facilitation of lordosis behavior in estrogen-primed rats by progesterone (P) and its 5α- and 5β-reduced metabolites, gonadotropin-releasing hormone (GnRH), leptin, prostaglandin E2 (PGE2) and vagino-cervical stimulation (VCS) involves interactions with classical ERs by using the selective ER modulator, tamoxifen. To further assess the role of ERs, we also explored the effects of the pure ER antagonist, ICI182780 (ICI), on estrous behavior induced by P and GnRH. Ovariectomized, estrogen-primed rats (5μg estradiol benzoate 40h earlier) were injected intraventricularly with the above-mentioned compounds, or they received VCS. All compounds and VCS effectively facilitated estrous behavior when tested at 60, 120 or 240min after infusion or application of VCS. Intraventricular infusion of tamoxifen (5μg), 30min before, significantly attenuated estrous behaviors induced in estradiol-primed rats by P, most of its 5α- and 5β-reduced metabolites, GnRH, and PGE2, but not by VCS. Although there was a trend for reduction, tamoxifen did not significantly decrease lordosis in females treated with 5β-pregnan-3,20-dione. ICI also inhibited lordosis behavior induced by P and GnRH at some testing intervals. These results suggest that activation of classical ERs participates in the triggering effects on estrous behavior induced by agents with different chemical structures that do not bind directly to ERs. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Bisphenol A and Related Alkylphenols Exert Nongenomic Estrogenic Actions Through a G Protein-Coupled Estrogen Receptor 1 (Gper)/Epidermal Growth Factor Receptor (Egfr) Pathway to Inhibit Meiotic Maturation of Zebrafish Oocytes1

    PubMed Central

    Fitzgerald, Amanda C.; Peyton, Candace; Dong, Jing; Thomas, Peter

    2015-01-01

    Xenobiotic estrogens, such as bisphenol A (BPA), disrupt a wide variety of genomic estrogen actions, but their nongenomic estrogen actions remain poorly understood. We investigated nongenomic estrogenic effects of low concentrations of BPA and three related alkylphenols on the inhibition of zebrafish oocye maturation (OM) mediated through a G protein-coupled estrogen receptor 1 (Gper)-dependent epidermal growth factor receptor (Egfr) pathway. BPA (10–100 nM) treatment for 3 h mimicked the effects of estradiol-17beta (E2) and EGF, decreasing spontaneous maturation of defolliculated zebrafish oocytes, an effect not blocked by coincubation with actinomycin D, but blocked by coincubation with a Gper antibody. BPA displayed relatively high binding affinity (15.8% that of E2) for recombinant zebrafish Gper. The inhibitory effects of BPA were attenuated by inhibition of upstream regulators of Egfr, intracellular tyrosine kinase (Src) with PP2, and matrix metalloproteinase with ilomastat. Treatment with an inhibitor of Egfr transactivation, AG1478, and an inhibitor of the mitogen-activated protein kinase (MAPK) 3/1 pathway, U0126, increased spontaneous OM and blocked the inhibitory effects of BPA, E2, and the selective GPER agonist, G-1. Western blot analysis showed that BPA (10–200 nM) mimicked the stimulatory effects of E2 and EGF on Mapk3/1 phosphorylation. Tetrabromobisphenol A, 4-nonylphenol, and tetrachlorobisphenol A (5–100 nM) also inhibited OM, an effect blocked by cotreatment with AG1478, as well as with the GPER antagonist, G-15, and displayed similar binding affinities as BPA to zebrafish Gper. The results suggest that BPA and related alkylphenols disrupt zebrafish OM by a novel nongenomic estrogenic mechanism involving activation of the Gper/Egfr/Mapk3/1 pathway. PMID:26490843

  15. Novel DNA Motif Binding Activity Observed In Vivo With an Estrogen Receptor α Mutant Mouse

    PubMed Central

    Li, Leping; Grimm, Sara A.; Winuthayanon, Wipawee; Hamilton, Katherine J.; Pockette, Brianna; Rubel, Cory A.; Pedersen, Lars C.; Fargo, David; Lanz, Rainer B.; DeMayo, Francesco J.; Schütz, Günther; Korach, Kenneth S.

    2014-01-01

    Estrogen receptor α (ERα) interacts with DNA directly or indirectly via other transcription factors, referred to as “tethering.” Evidence for tethering is based on in vitro studies and a widely used “KIKO” mouse model containing mutations that prevent direct estrogen response element DNA- binding. KIKO mice are infertile, due in part to the inability of estradiol (E2) to induce uterine epithelial proliferation. To elucidate the molecular events that prevent KIKO uterine growth, regulation of the pro-proliferative E2 target gene Klf4 and of Klf15, a progesterone (P4) target gene that opposes the pro-proliferative activity of KLF4, was evaluated. Klf4 induction was impaired in KIKO uteri; however, Klf15 was induced by E2 rather than by P4. Whole uterine chromatin immunoprecipitation-sequencing revealed enrichment of KIKO ERα binding to hormone response elements (HREs) motifs. KIKO binding to HRE motifs was verified using reporter gene and DNA-binding assays. Because the KIKO ERα has HRE DNA-binding activity, we evaluated the “EAAE” ERα, which has more severe DNA-binding domain mutations, and demonstrated a lack of estrogen response element or HRE reporter gene induction or DNA-binding. The EAAE mouse has an ERα null–like phenotype, with impaired uterine growth and transcriptional activity. Our findings demonstrate that the KIKO mouse model, which has been used by numerous investigators, cannot be used to establish biological functions for ERα tethering, because KIKO ERα effectively stimulates transcription using HRE motifs. The EAAE-ERα DNA-binding domain mutant mouse demonstrates that ERα DNA-binding is crucial for biological and transcriptional processes in reproductive tissues and that ERα tethering may not contribute to estrogen responsiveness in vivo. PMID:24713037

  16. The nuclear orphan receptors COUP-TF and ARP-1 positively regulate the trout estrogen receptor gene through enhancing autoregulation.

    PubMed Central

    Lazennec, G; Kern, L; Valotaire, Y; Salbert, G

    1997-01-01

    The rainbow trout estrogen receptor (rtER) is a positively autoregulated gene in liver cells. In a previous report, we showed that upregulation is mediated by an estrogen response element (ERE) located in the proximal promoter of the gene and that a half binding site for nuclear receptors (5'-TGACCT-3') located 15 bp upstream of the ERE is involved in the magnitude of the estrogen response. We now report that the human orphan receptor COUP-TF and a COUP-TF-like protein from trout liver are able to bind to the consensus half-site. When cotransfected with the rtER gene proximal promoter, COUP-TF had no regulatory functions on its own. Interestingly, COUP-TF enhanced rtER transactivation properties in the presence of estradiol in a dose-dependent manner when cotransfected with the rtER gene promoter. Unliganded retinoid receptor heterodimers had the same helper function as COUP-TF in the presence of estradiol but were switched to repressors when the ligand all-trans-retinoic acid was added. Mutation of the consensus half-site only slightly reduced COUP-TF helper function, suggesting that it actually results from a complex mechanism that probably involves both DNA binding of COUP-TF to the promoter and protein-protein interaction with another transcription factor bound to the promoter. Nevertheless, a DNA-binding-defective mutant of COUP-TF was also defective in ER helper function. Competition footprinting analysis suggested that COUP-TF actually establishes contacts with the consensus upstream half-site and the downstream ERE half-site that would form a DR-24-like response element. Interaction of COUP-TF with the DR-24 element was confirmed in footprinting assays by using nuclear extracts from Saccharomyces cerevisiae expressing COUP-TF. Finally, interaction of COUP-TF with mutants of the rtER gene promoter showed that COUP-TF recognizes the ERE when the upstream half-site is mutated. These data show that COUP-TF may activate transcription through interaction with

  17. Expression of Estrogen Receptors in Relation to Hormone Levels and the Nottingham Prognostic Index.

    PubMed

    Fahlén, Mia; Zhang, Hua; Löfgren, Lars; Masironi, Britt; VON Schoultz, Eva; VON Schoultz, B O; Sahlin, Lena

    2016-06-01

    Estrogen hormones have a large impact on both normal development and tumorigenesis of the breast. Breast tissue samples from 49 women undergoing surgery were included. The estrogen receptors (ERα and ERβ), ERα36 and G-coupled estrogen receptor-1 (GPER) were determined in benign and malignant breast tissue. The ERα36 and ERα mRNA levels were highest in malignant tumors. Stromal ERβ immunostaining in benign tumors was higher than in the paired normal tissue. GPER expression was lowest in benign tumors. In the malignant tumors, the Nottingham Prognostic Index (NPI) correlated positively with stromal GPER and the serum testosterone level. The serum insulin-like growth factor-1 (IGF-1) level correlated negatively with GPER mRNA and glandular ERα. The expression of ERα36 is stronger in malignant breast tissue. The strong positive correlation between NPI and GPER in malignant breast stroma indicates an important role for GPER in breast cancer prognosis. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  18. Regulation of expression of hyperalgesic priming by estrogen receptor alpha in the rat

    PubMed Central

    Ferrari, Luiz F.; Araldi, Dionéia; Levine, Jon D.

    2017-01-01

    Hyperalgesic priming, a sexually dimorphic model of transition to chronic pain, is expressed as prolongation of prostaglandin E2 (PGE2)-induced hyperalgesia by the activation of an additional pathway including an autocrine mechanism at the plasma membrane. The autocrine mechanism involves the transport of cAMP to the extracellular space, and its conversion to AMP and adenosine, by ecto-5′phosphodiesterase and ecto-5′nucleotidase, respectively. The end product, adenosine, activates A1 receptors, producing delayed onset prolongation of PGE2 hyperalgesia. We tested the hypothesis that the previously reported, estrogen-dependent, sexual dimorphism observed in the induction of priming is present in the mechanisms involved in its expression, as a regulatory effect on ecto-5′nucleotidase by estrogen receptor alpha (EsRα), in female rats. In the primed paw AMP hyperalgesia was dependent on conversion to adenosine, being prevented by ecto-5′nucleotidase inhibitor AMPCP and A1 receptor antagonist DPCPX. To investigate an interaction between EsRα and ecto-5′nucleotidase, we treated primed female rats with ODN antisense or mismatch against EsRα mRNA. While in rats treated with antisense AMP-induced hyperalgesia was abolished, the A1 receptor agonist N6-cyclopentiladenosine (CPA) still produced hyperalgesia. Thus, EsRα interacts with this autocrine pathway at the level of ecto-5′nucleotidase. These results demonstrate a sexually dimorphic mechanism for the expression of priming. Perspective This study presents evidence of an estrogen-dependent mechanism of expression of chronic pain in females, supporting the suggestion that differential targets must be considered when establishing protocols for the treatment of painful conditions in males and females. PMID:28089711

  19. Binding of alkylphenols and alkylated non-phenolics to rainbow trout (Oncorhynchus mykiss) hepatic estrogen receptors.

    PubMed

    Tollefsen, Knut-Erik; Julie Nilsen, Anja

    2008-02-01

    Alkylphenols are well-known endocrine disrupters, mediating effects through the estrogen receptor (ER). In the present work, the interaction of alkylphenols and alkylated non-phenolics with hepatic rainbow trout (Oncorhynchus mykiss) estrogen receptors (rtERs) was determined. The role of alkyl chain length and branching, substituent position, number of alkylated groups, and the requirement of a phenolic ring structure was assessed. The results showed that the rtERs bound most alkylphenols, although with 20,000 to 2 million times lower affinity than the endogenous estrogen 17beta-estradiol. Mono-substituted alkylphenols with moderate (C4-C6) and long (C8 and C12) alkyl chain length in the para position exhibited the highest affinity for the rtERs. Substitution with multiple alkyl groups, presence of substituents in the ortho- and meta-position, and lack of a hydroxyl group on the benzene ring reduced the binding affinity. The rtERs resembled the reported binding specificity of the human ER for alkylphenols, although some exceptions were identified.

  20. Estrogens Induce Rapid Cytoskeleton Re-Organization in Human Dermal Fibroblasts via the Non-Classical Receptor GPR30

    PubMed Central

    Carnesecchi, Julie; Malbouyres, Marilyne; de Mets, Richard; Balland, Martial; Beauchef, Gallic; Vié, Katell; Chamot, Christophe; Lionnet, Claire; Ruggiero, Florence; Vanacker, Jean-Marc

    2015-01-01

    The post-menopausal decrease in estrogen circulating levels results in rapid skin deterioration pointing out to a protective effect exerted by these hormones. The identity of the skin cell type responding to estrogens is unclear as are the cellular and molecular processes they elicit. Here, we reported that lack of estrogens induces rapid re-organization of the human dermal fibroblast cytoskeleton resulting in striking cell shape change. This morphological change was accompanied by a spatial re-organization of focal adhesion and a substantial reduction of their number as evidenced by vinculin and actin co-staining. Cell morphology and cytoskeleton organization was fully restored upon 17β-estradiol (E2) addition. Treatment with specific ER antagonists and cycloheximide respectively showed that the E2 acts independently of the classical Estrogen Receptors and that cell shape change is mediated by non-genomic mechanisms. E2 treatment resulted in a rapid and transient activation of ERK1/2 but not Src or PI3K. We show that human fibroblasts express the non-classical E2 receptor GPR30 and that its agonist G-1 phenocopies the effect of E2. Inhibiting GPR30 through treatment with the G-15 antagonist or specific shRNA impaired E2 effects. Altogether, our data reveal a novel mechanism by which estrogens act on skin fibroblast by regulating cell shape through the non-classical G protein-coupled receptor GPR30 and ERK1/2 activation. PMID:25781607

  1. Estrogens induce rapid cytoskeleton re-organization in human dermal fibroblasts via the non-classical receptor GPR30.

    PubMed

    Carnesecchi, Julie; Malbouyres, Marilyne; de Mets, Richard; Balland, Martial; Beauchef, Gallic; Vié, Katell; Chamot, Christophe; Lionnet, Claire; Ruggiero, Florence; Vanacker, Jean-Marc

    2015-01-01

    The post-menopausal decrease in estrogen circulating levels results in rapid skin deterioration pointing out to a protective effect exerted by these hormones. The identity of the skin cell type responding to estrogens is unclear as are the cellular and molecular processes they elicit. Here, we reported that lack of estrogens induces rapid re-organization of the human dermal fibroblast cytoskeleton resulting in striking cell shape change. This morphological change was accompanied by a spatial re-organization of focal adhesion and a substantial reduction of their number as evidenced by vinculin and actin co-staining. Cell morphology and cytoskeleton organization was fully restored upon 17β-estradiol (E2) addition. Treatment with specific ER antagonists and cycloheximide respectively showed that the E2 acts independently of the classical Estrogen Receptors and that cell shape change is mediated by non-genomic mechanisms. E2 treatment resulted in a rapid and transient activation of ERK1/2 but not Src or PI3K. We show that human fibroblasts express the non-classical E2 receptor GPR30 and that its agonist G-1 phenocopies the effect of E2. Inhibiting GPR30 through treatment with the G-15 antagonist or specific shRNA impaired E2 effects. Altogether, our data reveal a novel mechanism by which estrogens act on skin fibroblast by regulating cell shape through the non-classical G protein-coupled receptor GPR30 and ERK1/2 activation.

  2. Effects of atrazine on estrogen receptor α- and G protein-coupled receptor 30-mediated signaling and proliferation in cancer cells and cancer-associated fibroblasts.

    PubMed

    Albanito, Lidia; Lappano, Rosamaria; Madeo, Antonio; Chimento, Adele; Prossnitz, Eric R; Cappello, Anna Rita; Dolce, Vincenza; Abonante, Sergio; Pezzi, Vincenzo; Maggiolini, Marcello

    2015-05-01

    The pesticide atrazine does not bind to or activate the classical estrogen receptor (ER), but it up-regulates the aromatase activity in estrogen-sensitive tumor cells. The G protein estrogen receptor (GPR30/GPER) has been reported to be involved in certain biological responses to endogenous estrogens and environmental compounds exerting estrogen-like activity. We aimed to evaluate the potential of atrazine to trigger GPER-mediated signaling in cancer cells and cancer-associated fibroblasts (CAFs). Using gene reporter assays in diverse types of cancer cells, we found that atrazine did not transactivate endogenous ERα or chimeric proteins that encode the ERα and ERβ hormone binding domains. Conversely, atrazine was able to bind to GPER to induce ERK activation and the expression of estrogen target genes, which, interestingly, appeared to rely on both GPER and ERα expression. As a biological counterpart, atrazine stimulated the proliferation of ovarian cancer cells that depend on GPER and ERα, as evidenced by gene silencing experiments and the use of specific signaling inhibitors. Of note, through GPER, atrazine elicited ERK phosphorylation, gene expression, and migration in CAFs, thus extending its stimulatory role to these main players of the tumor microenvironment. Our results suggest a novel mechanism through which atrazine may exert relevant biological effects in cancer cells and CAFs. On the basis of our data, atrazine should be included among the environmental contaminants that may elicit estrogenic activity through GPER-mediated signaling.

  3. Distinct Effects of Estrogen on Mouse Maternal Behavior: The Contribution of Estrogen Synthesis in the Brain

    PubMed Central

    Murakami, Gen

    2016-01-01

    Estrogen surge following progesterone withdrawal at parturition plays an important role in initiating maternal behavior in various rodent species. Systemic estrogen treatment shortens the latency to onset of maternal behavior in nulliparous female rats that have not experienced parturition. In contrast, nulliparous laboratory mice show rapid onset of maternal behavior without estrogen treatment, and the role of estrogen still remains unclear. Here the effect of systemic estrogen treatment (for 2 h, 1 day, 3 days, and 7 days) after progesterone withdrawal was examined on maternal behavior of C57BL/6 mice. This estrogen regimen led to different effects on nursing, pup retrieval, and nest building behaviors. Latency to nursing was shortened by estrogen treatment within 2 h. Moreover, pup retrieval and nest building were decreased. mRNA expression was also investigated for estrogen receptor α (ERα) and for genes involved in regulating maternal behavior, specifically, the oxytocin receptor (OTR) and vasopressin receptor in the medial amygdala (MeA) and medial preoptic area (MPOA). Estrogen treatment led to decreased ERα mRNA in both regions. Although OTR mRNA was increased in the MeA, OTR and vasopressin receptor mRNA were reduced in the MPOA, showing region-dependent transcription regulation. To determine the mechanisms for the actions of estrogen treatment, the contribution of estrogen synthesis in the brain was examined. Blockade of estrogen synthesis in the brain by systemic letrozole treatment in ovariectomized mice interfered with pup retrieval and nest building but not nursing behavior, indicating different contributions of estrogen synthesis to maternal behavior. Furthermore, letrozole treatment led to an increase in ERα mRNA in the MeA but not in the MPOA, suggesting that involvement of estrogen synthesis is brain region dependent. Altogether, these results suggest that region-dependent estrogen synthesis leads to differential transcriptional activation due

  4. Genistein and bisphenol A exposure cause estrogen receptor 1 to bind thousands of sites in a cell type-specific manner

    PubMed Central

    Gertz, Jason; Reddy, Timothy E.; Varley, Katherine E.; Garabedian, Michael J.; Myers, Richard M.

    2012-01-01

    Endogenous estrogens that are synthesized in the body impact gene regulation by activating estrogen receptors in diverse cell types. Exogenous compounds that have estrogenic properties can also be found circulating in the blood in both children and adults. The genome-wide impact of these environmental estrogens on gene regulation is unclear. To obtain an integrated view of gene regulation in response to environmental and endogenous estrogens on a genome-wide scale, we performed ChIP-seq to identify estrogen receptor 1 (ESR1; previously estrogen receptor α) binding sites, and RNA-seq in endometrial cancer cells exposed to bisphenol A (BPA; found in plastics), genistein (GEN; found in soybean), or 17β-estradiol (E2; an endogenous estrogen). GEN and BPA treatment induces thousands of ESR1 binding sites and >50 gene expression changes, representing a subset of E2-induced gene regulation changes. Genes affected by E2 were highly enriched for ribosome-associated proteins; however, GEN and BPA failed to regulate most ribosome-associated proteins and instead enriched for transporters of carboxylic acids. Treatment-dependent changes in gene expression were associated with treatment-dependent ESR1 binding sites, with the exception that many genes up-regulated by E2 harbored a BPA-induced ESR1 binding site but failed to show any expression change after BPA treatment. GEN and BPA exhibited a similar relationship to E2 in the breast cancer line T-47D, where cell type specificity played a much larger role than treatment specificity. Overall, both environmental estrogens clearly regulate gene expression through ESR1 on a genome-wide scale, although with lower potency resulting in less ESR1 binding sites and less gene expression changes compared to the endogenous estrogen, E2. PMID:23019147

  5. A novel carborane analog, BE360, with a carbon-containing polyhedral boron-cluster is a new selective estrogen receptor modulator for bone

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hirata, Michiko; Inada, Masaki; Matsumoto, Chiho

    Carboranes are a class of carbon-containing polyhedral boron-cluster compounds with globular geometry and hydrophobic surface that interact with hormone receptors. Estrogen deficiency results in marked bone loss due to increased osteoclastic bone resorption in females, but estrogen replacement therapy is not generally used for postmenopausal osteoporosis due to the risk of uterine cancer. We synthesized a novel carborane compound BE360 to clarify its anti-osteoporosis activity. BE360 showed a high binding affinity to estrogen receptors (ER), ER{alpha} and ER{beta}. In ovariectomized (OVX) mice, femoral bone volume was markedly reduced and BE360 dose-dependently restored bone loss in OVX mice. However, BE360 didmore » not exhibit any estrogenic activity in the uterus. BE360 also restored bone loss in orchidectomized mice without androgenic action in the sex organs. Therefore, BE360 is a novel selective estrogen receptor modulator (SERM) that may offer a new therapy option for osteoporosis.« less

  6. BPA Directly Decreases GnRH Neuronal Activity via Noncanonical Pathway.

    PubMed

    Klenke, Ulrike; Constantin, Stephanie; Wray, Susan

    2016-05-01

    Peripheral feedback of gonadal estrogen to the hypothalamus is critical for reproduction. Bisphenol A (BPA), an environmental pollutant with estrogenic actions, can disrupt this feedback and lead to infertility in both humans and animals. GnRH neurons are essential for reproduction, serving as an important link between brain, pituitary, and gonads. Because GnRH neurons express several receptors that bind estrogen, they are potential targets for endocrine disruptors. However, to date, direct effects of BPA on GnRH neurons have not been shown. This study investigated the effects of BPA on GnRH neuronal activity using an explant model in which large numbers of primary GnRH neurons are maintained and express many of the receptors found in vivo. Because oscillations in intracellular calcium have been shown to correlate with electrical activity in GnRH neurons, calcium imaging was used to assay the effects of BPA. Exposure to 50μM BPA significantly decreased GnRH calcium activity. Blockage of γ-aminobutyric acid ergic and glutamatergic input did not abrogate the inhibitory BPA effect, suggesting direct regulation of GnRH neurons by BPA. In addition to estrogen receptor-β, single-cell RT-PCR analysis confirmed that GnRH neurons express G protein-coupled receptor 30 (G protein-coupled estrogen receptor 1) and estrogen-related receptor-γ, all potential targets for BPA. Perturbation studies of the signaling pathway revealed that the BPA-mediated inhibition of GnRH neuronal activity occurred independent of estrogen receptors, GPER, or estrogen-related receptor-γ, via a noncanonical pathway. These results provide the first evidence of a direct effect of BPA on GnRH neurons.

  7. BPA Directly Decreases GnRH Neuronal Activity via Noncanonical Pathway

    PubMed Central

    Klenke, Ulrike; Constantin, Stephanie

    2016-01-01

    Peripheral feedback of gonadal estrogen to the hypothalamus is critical for reproduction. Bisphenol A (BPA), an environmental pollutant with estrogenic actions, can disrupt this feedback and lead to infertility in both humans and animals. GnRH neurons are essential for reproduction, serving as an important link between brain, pituitary, and gonads. Because GnRH neurons express several receptors that bind estrogen, they are potential targets for endocrine disruptors. However, to date, direct effects of BPA on GnRH neurons have not been shown. This study investigated the effects of BPA on GnRH neuronal activity using an explant model in which large numbers of primary GnRH neurons are maintained and express many of the receptors found in vivo. Because oscillations in intracellular calcium have been shown to correlate with electrical activity in GnRH neurons, calcium imaging was used to assay the effects of BPA. Exposure to 50μM BPA significantly decreased GnRH calcium activity. Blockage of γ-aminobutyric acid ergic and glutamatergic input did not abrogate the inhibitory BPA effect, suggesting direct regulation of GnRH neurons by BPA. In addition to estrogen receptor-β, single-cell RT-PCR analysis confirmed that GnRH neurons express G protein-coupled receptor 30 (G protein-coupled estrogen receptor 1) and estrogen-related receptor-γ, all potential targets for BPA. Perturbation studies of the signaling pathway revealed that the BPA-mediated inhibition of GnRH neuronal activity occurred independent of estrogen receptors, GPER, or estrogen-related receptor-γ, via a noncanonical pathway. These results provide the first evidence of a direct effect of BPA on GnRH neurons. PMID:26934298

  8. CLONING AND IN VITRO EXPRESSION AND CHARACTERIZATION OF THE ANDROGEN RECEPTOR AND ISOLATION OF ESTROGEN RECEPTOR α FROM THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    In vitro screening assays designed to identify hormone mimics or antagonists typically use mammalian (rat, human) estrogen (ER) and androgen receptors (AR). Although we know that the amino acid sequences of steroid receptors in nonmammalian vertebrates are not identical to the ma...

  9. Exclusive nuclear location of estrogen receptors in Squalus testis.

    PubMed Central

    Callard, G V; Mak, P

    1985-01-01

    An estrogen (E)-binding molecule having both occupied and unoccupied sites is restricted to nuclear subfractions in the testis of the spiny dogfish (Squalus acanthias). We investigated the hypothesis that a species characterized by high body-fluid osmolarity (1010 mosM) has an estrogen receptor (ER) that binds to chromatin with high affinity and consequently resists redistribution during tissue processing. Although the steroid binding and sedimentation properties of the Squalus nuclear ER conformed to those of classical ER, its elution maximum from DNA-cellulose was unusually high (0.55 M NaCl). A tendency to adhere tightly to cell nuclei was reflected in the high salt concentration (0.43 M KCl) required to extract 50% of the receptors from the nuclear compartment during homogenization and in the stability of the nuclear ER population in the presence of high concentrations of a nonionic solute (urea) or increased buffer volume. Mixing and redistribution experiments showed that nuclear ER could be quantitatively and qualitatively measured in cytosolic extracts, ruling out the possibility that soluble receptors were being masked. Although Squalus oviduct ER was similar to that of testis, ER in the testis and liver of a related elasmobranch (Potamotrygon) that maintains osmotic equilibrium at 300 mosM more closely resembled mammalian ER in its elution maximum from DNA-cellulose (0.22 M NaCl) and cytosolic/nuclear ratios in low-salt buffers. We conclude that Squalus testis has a single ER pool located exclusively in the nuclear compartment. These observations support a revised concept of steroid action and further indicate that the chromatin affinity of the hormone-ER complex is an important factor in determining subfractional distribution during tissue processing. PMID:3856265

  10. U-Shape Suppressive Effect of Phenol Red on the Epileptiform Burst Activity via Activation of Estrogen Receptors in Primary Hippocampal Culture

    PubMed Central

    Liu, Xu; Chen, Ben; Chen, Lulan; Ren, Wan-Ting; Liu, Juan; Wang, Guoxiang; Fan, Wei; Wang, Xin; Wang, Yun

    2013-01-01

    Phenol red is widely used in cell culture as a pH indicator. Recently, it also has been reported to have estrogen-like bioactivity and be capable of promoting cell proliferation in different cell lines. However, the effect of phenol red on primary neuronal culture has never been investigated. By using patch clamp technique, we demonstrated that hippocampal pyramidal neurons cultured in neurobasal medium containing no phenol red had large depolarization-associated epileptiform bursting activities, which were rarely seen in neurons cultured in phenol red-containing medium. Further experiment data indicate that the suppressive effect of the phenol red on the abnormal epileptiform burst neuronal activities was U-shape dose related, with the most effective concentration at 28 µM. In addition, this concentration related inhibitory effect of phenol red on the epileptiform neuronal discharges was mimicked by 17-β-estradiol, an estrogen receptor agonist, and inhibited by ICI-182,780, an estrogen receptor antagonist. Our results suggest that estrogen receptor activation by phenol red in the culture medium prevents formation of abnormal, epileptiform burst activity. These studies highlight the importance of phenol red as estrogen receptor stimulator and cautions of careful use of phenol red in cell culture media. PMID:23560076

  11. Protein Kinase Cα Modulates Estrogen-Receptor-Dependent Transcription and Proliferation in Endometrial Cancer Cells

    PubMed Central

    Thorne, Alicia M.; Jackson, Twila A.; Willis, Van C.; Bradford, Andrew P.

    2013-01-01

    Endometrial cancer is the most common invasive gynecologic malignancy in developed countries. The most prevalent endometrioid tumors are linked to excessive estrogen exposure and hyperplasia. However, molecular mechanisms and signaling pathways underlying their etiology and pathophysiology remain poorly understood. We have shown that protein kinase Cα (PKCα) is aberrantly expressed in endometrioid tumors and is an important mediator of endometrial cancer cell survival, proliferation, and invasion. In this study, we demonstrate that expression of active, myristoylated PKCα conferred ligand-independent activation of estrogen-receptor- (ER-) dependent promoters and enhanced responses to estrogen. Conversely, knockdown of PKCα reduced ER-dependent gene expression and inhibited estrogen-induced proliferation of endometrial cancer cells. The ability of PKCα to potentiate estrogen activation of ER-dependent transcription was attenuated by inhibitors of phosphoinositide 3-kinase (PI3K) and Akt. Evidence suggests that PKCα and estrogen signal transduction pathways functionally interact, to modulate ER-dependent growth and transcription. Thus, PKCα signaling, via PI3K/Akt, may be a critical element of the hyperestrogenic environment and activation of ER that is thought to underlie the development of estrogen-dependent endometrial hyperplasia and malignancy. PKCα-dependent pathways may provide much needed prognostic markers of aggressive disease and novel therapeutic targets in ER positive tumors. PMID:23843797

  12. Evaluation of estrogen receptor alpha activation by glyphosate-based herbicide constituents.

    PubMed

    Mesnage, Robin; Phedonos, Alexia; Biserni, Martina; Arno, Matthew; Balu, Sucharitha; Corton, J Christopher; Ugarte, Ricardo; Antoniou, Michael N

    2017-10-01

    The safety, including the endocrine disruptive capability, of glyphosate-based herbicides (GBHs) is a matter of intense debate. We evaluated the estrogenic potential of glyphosate, commercial GBHs and polyethoxylated tallowamine adjuvants present as co-formulants in GBHs. Glyphosate (≥10,000 μg/L or 59 μM) promoted proliferation of estrogen-dependent MCF-7 human breast cancer cells. Glyphosate also increased the expression of an estrogen response element-luciferase reporter gene (ERE-luc) in T47D-KBluc cells, which was blocked by the estrogen antagonist ICI 182,780. Commercial GBH formulations or their adjuvants alone did not exhibit estrogenic effects in either assay. Transcriptomics analysis of MCF-7 cells treated with glyphosate revealed changes in gene expression reflective of hormone-induced cell proliferation but did not overlap with an ERα gene expression biomarker. Calculation of glyphosate binding energy to ERα predicts a weak and unstable interaction (-4.10 kcal mol -1 ) compared to estradiol (-25.79 kcal mol -1 ), which suggests that activation of this receptor by glyphosate is via a ligand-independent mechanism. Induction of ERE-luc expression by the PKA signalling activator IBMX shows that ERE-luc is responsive to ligand-independent activation, suggesting a possible mechanism of glyphosate-mediated activation. Our study reveals that glyphosate, but not other components present in GBHs, can activate ERα in vitro, albeit at relatively high concentrations. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. The role of estrogen in pubertal skeletal physiology: epiphyseal maturation and mineralization of the skeleton.

    PubMed

    Frank, G R

    1995-06-01

    The year 1994 is likely to be remembered by many endocrinologists as the year in which dramatic new light was shed on the role played by estrogen in human skeletal physiology. It was in 1994 that two new syndromes were described, each representing a human model in which estrogen action was lacking. The first case was a female with an aromatase defect and a resultant inability to synthesize estrogen, and the second case was a man with an estrogen receptor gene defect that resulted in a non-functioning estrogen receptor and complete estrogen resistance. By examining the phenotypes of these two individuals, we were able, for the first time, to see what pubertal skeletal changes occur in the absence of estrogen action and directly extrapolate the role of estrogen in skeletal physiology. What has become abundantly clear is that it is estrogen and not androgen that is responsible for pubertal epiphyseal maturation and skeletal mineralization.

  14. Small-Molecule “BRCA1-Mimetics” Are Antagonists of Estrogen Receptor

    PubMed Central

    Ma, Yongxian; Tomita, York; Preet, Anju; Clarke, Robert; Englund, Erikah; Grindrod, Scott; Nathan, Shyam; De Oliveira, Eliseu; Brown, Milton L.

    2014-01-01

    Context: Resistance to conventional antiestrogens is a major cause of treatment failure and, ultimately, death in breast cancer. Objective: The objective of the study was to identify small-molecule estrogen receptor (ER)-α antagonists that work differently from tamoxifen and other selective estrogen receptor modulators. Design: Based on in silico screening of a pharmacophore database using a computed model of the BRCA1-ER-α complex (with ER-α liganded to 17β-estradiol), we identified a candidate group of small-molecule compounds predicted to bind to a BRCA1-binding interface separate from the ligand-binding pocket and the coactivator binding site of ER-α. Among 40 candidate compounds, six inhibited estradiol-stimulated ER-α activity by at least 50% in breast carcinoma cells, with IC50 values ranging between 3 and 50 μM. These ER-α inhibitory compounds were further studied by molecular and cell biological techniques. Results: The compounds strongly inhibited ER-α activity at concentrations that yielded little or no nonspecific toxicity, but they produced only a modest inhibition of progesterone receptor activity. Importantly, the compounds blocked proliferation and inhibited ER-α activity about equally well in antiestrogen-sensitive and antiestrogen-resistant breast cancer cells. Representative compounds disrupted the interaction of BRCA1 and ER-α in the cultured cells and blocked the interaction of ER-α with the estrogen response element. However, the compounds had no effect on the total cellular ER-α levels. Conclusions: These findings suggest that we have identified a new class of ER-α antagonists that work differently from conventional antiestrogens (eg, tamoxifen and fulvestrant). PMID:25264941

  15. Expression patterns of STAT3, ERK and estrogen-receptor α are associated with development and histologic severity of hepatic steatosis: a retrospective study.

    PubMed

    Choi, Euno; Kim, Won; Joo, Sae Kyung; Park, Sunyoung; Park, Jeong Hwan; Kang, Yun Kyung; Jin, So-Young; Chang, Mee Soo

    2018-04-03

    Hepatic steatosis renders hepatocytes vulnerable to injury, resulting in the progression of preexisting liver disease. Previous animal and cell culture studies implicated mammalian target of rapamycin (mTOR), signal transducer and activator of transcription-3 (STAT3), extracellular signal-regulated kinase (ERK) and estrogen-receptor α in the pathogenesis of hepatic steatosis and disease progression. However, to date there have been few studies performed using human liver tissue to study hepatic steatosis. We examined the expression patterns of mTOR, STAT3, ERK and estrogen-receptor α in liver tissues from patients diagnosed with hepatic steatosis. We reviewed the clinical and histomorphological features of 29 patients diagnosed with hepatic steatosis: 18 with non-alcoholic fatty liver disease (NAFLD), 11 with alcoholic fatty acid disease (AFLD), and a control group (16 biliary cysts and 22 hepatolithiasis). Immunohistochemistry was performed on liver tissue using an automated immunostainer. The histologic severity of hepatic steatosis was evaluated by assessing four key histomorphologic parameters common to NAFLD and AFLD: steatosis, lobular inflammation, ballooning degeneration and fibrosis. mTOR, phosphorylated STAT3, phosphorylated pERK, estrogen-receptor α were found to be more frequently expressed in the hepatic steatosis group than in the control group. Specifically, mTOR was expressed in 78% of hepatocytes, and ERK in 100% of hepatic stellate cells, respectively, in patients with NAFLD. Interestingly, estrogen-receptor α was diffusely expressed in hepatocytes in all NALFD cases. Phosphorylated (active) STAT3 was expressed in 73% of hepatocytes and 45% of hepatic stellate cells in patients with AFLD, and phosphorylated (active) ERK was expressed in hepatic stellate cells in all AFLD cases. Estrogen-receptor α was expressed in all AFLD cases (focally in 64% of AFLD cases, and diffusely in 36%). Phosphorylated STAT3 expression in hepatocytes and hepatic

  16. Estrogen and androgen receptor activities of hydraulic fracturing chemicals and surface and ground water in a drilling-dense region

    USGS Publications Warehouse

    Kassotis, Christopher D.; Tillitt, Donald E.; Davis, J. Wade; Hormann, Anette M.; Nagel, Susan C.

    2014-01-01

    The rapid rise in natural gas extraction using hydraulic fracturing increases the potential for contamination of surface and ground water from chemicals used throughout the process. Hundreds of products containing more than 750 chemicals and components are potentially used throughout the extraction process, including more than 100 known or suspected endocrine-disrupting chemicals. We hypothesized thataselected subset of chemicalsusedin natural gas drilling operationsandalso surface and ground water samples collected in a drilling-dense region of Garfield County, Colorado, would exhibit estrogen and androgen receptor activities. Water samples were collected, solid-phase extracted, and measured for estrogen and androgen receptor activities using reporter gene assays in human cell lines. Of the 39 unique water samples, 89%, 41%, 12%, and 46% exhibited estrogenic, antiestrogenic, androgenic, and antiandrogenic activities, respectively. Testing of a subset of natural gas drilling chemicals revealed novel antiestrogenic, novel antiandrogenic, and limited estrogenic activities. The Colorado River, the drainage basin for this region, exhibited moderate levels of estrogenic, antiestrogenic, and antiandrogenic activities, suggesting that higher localized activity at sites with known natural gas–related spills surrounding the river might be contributing to the multiple receptor activities observed in this water source. The majority of water samples collected from sites in a drilling-dense region of Colorado exhibited more estrogenic, antiestrogenic, or antiandrogenic activities than reference sites with limited nearby drilling operations. Our data suggest that natural gas drilling operationsmayresult in elevated endocrine-disrupting chemical activity in surface and ground water.

  17. Role of Estrogens in the Regulation of Liver Lipid Metabolism.

    PubMed

    Palmisano, Brian T; Zhu, Lin; Stafford, John M

    2017-01-01

    Before menopause, women are protected from atherosclerotic heart disease associated with obesity relative to men. Sex hormones have been proposed as a mechanism that differentiates this risk. In this review, we discuss the literature around how the endogenous sex hormones and hormone treatment approaches after menopause regulate fatty acid, triglyceride, and cholesterol metabolism to influence cardiovascular risk.The important regulatory functions of estrogen signaling pathways with regard to lipid metabolism have been in part obscured by clinical trials with hormone treatment of women after menopause, due to different formulations, routes of delivery, and pairings with progestins. Oral hormone treatment with several estrogen preparations increases VLDL triglyceride production. Progestins oppose this effect by stimulating VLDL clearance in both humans and animals. Transdermal estradiol preparations do not increase VLDL production or serum triglycerides.Many aspects of sex differences in atherosclerotic heart disease risk are influenced by the distributed actions of estrogens in the muscle, adipose, and liver. In humans, 17β-estradiol (E2) is the predominant circulating estrogen and signals through estrogen receptor alpha (ERα), estrogen receptor beta (ERβ), and G-protein-coupled estrogen receptor (GPER). Over 1000 human liver genes display a sex bias in their expression, and the top biological pathways are in lipid metabolism and genes related to cardiovascular disease. Many of these genes display variation depending on estrus cycling in the mouse. Future directions will likely rely on targeting estrogens to specific tissues or specific aspects of the signaling pathways in order to recapitulate the protective physiology of premenopause therapeutically after menopause.

  18. 17β-Estradiol and Agonism of G-protein-Coupled Estrogen Receptor Enhance Hippocampal Memory via Different Cell-Signaling Mechanisms

    PubMed Central

    Kim, Jaekyoon; Szinte, Julia S.; Boulware, Marissa I.

    2016-01-01

    The ability of 17β-estradiol (E2) to enhance hippocampal object recognition and spatial memory depends on rapid activation of extracellular signal-regulated kinase (ERK) in the dorsal hippocampus (DH). Although this activation can be mediated by the intracellular estrogen receptors ERα and ERβ, little is known about the role that the membrane estrogen receptor GPER plays in regulating ERK or E2-mediated memory formation. In this study, post-training DH infusion of the GPER agonist G-1 enhanced object recognition and spatial memory in ovariectomized female mice, whereas the GPER antagonist G-15 impaired memory, suggesting that GPER activation, like E2, promotes hippocampal memory formation. However, unlike E2, G-1 did not increase ERK phosphorylation, but instead significantly increased phosphorylation of c-Jun N-terminal kinase (JNK) in the DH. Moreover, DH infusion of the JNK inhibitor SP600125 prevented G-1 from enhancing object recognition and spatial memory, but the ERK inhibitor U0126 did not. These data suggest that GPER enhances memory via different cell-signaling mechanisms than E2. This conclusion was supported by data showing that the ability of E2 to facilitate memory and activate ERK signaling was not blocked by G-15 or SP600125, which demonstrates that the memory-enhancing effects of E2 are not dependent on JNK or GPER activation in the DH. Together, these data indicate that GPER regulates memory independently from ERα and ERβ by activating JNK signaling, rather than ERK signaling. Thus, the findings suggest that GPER in the DH may not function as an estrogen receptor to regulate object recognition and spatial memory. SIGNIFICANCE STATEMENT Although 17β-estradiol has long been known to regulate memory function, the molecular mechanisms underlying estrogenic memory modulation remain largely unknown. Here, we examined whether the putative membrane estrogen receptor GPER acts like the classical estrogen receptors, ERα and ERβ, to facilitate

  19. Beta-Estradiol Regulates Voltage-Gated Calcium Channels and Estrogen Receptors in Telocytes from Human Myometrium.

    PubMed

    Banciu, Adela; Banciu, Daniel Dumitru; Mustaciosu, Cosmin Catalin; Radu, Mihai; Cretoiu, Dragos; Xiao, Junjie; Cretoiu, Sanda Maria; Suciu, Nicolae; Radu, Beatrice Mihaela

    2018-05-09

    Voltage-gated calcium channels and estrogen receptors are essential players in uterine physiology, and their association with different calcium signaling pathways contributes to healthy and pathological conditions of the uterine myometrium. Among the properties of the various cell subtypes present in human uterine myometrium, there is increasing evidence that calcium oscillations in telocytes (TCs) contribute to contractile activity and pregnancy. Our study aimed to evaluate the effects of beta-estradiol on voltage-gated calcium channels and estrogen receptors in TCs from human uterine myometrium and to understand their role in pregnancy. For this purpose, we employed patch-clamp recordings, ratiometric Fura-2-based calcium imaging analysis, and qRT-PCR techniques for the analysis of cultured human myometrial TCs derived from pregnant and non-pregnant uterine samples. In human myometrial TCs from both non-pregnant and pregnant uterus, we evidenced by qRT-PCR the presence of genes encoding for voltage-gated calcium channels (Cav3.1, Ca3.2, Cav3.3, Cav2.1), estrogen receptors (ESR1, ESR2, GPR30), and nuclear receptor coactivator 3 (NCOA3). Pregnancy significantly upregulated Cav3.1 and downregulated Cav3.2, Cav3.3, ESR1, ESR2, and NCOA3, compared to the non-pregnant condition. Beta-estradiol treatment (24 h, 10, 100, 1000 nM) downregulated Cav3.2, Cav3.3, Cav1.2, ESR1, ESR2, GRP30, and NCOA3 in TCs from human pregnant uterine myometrium. We also confirmed the functional expression of voltage-gated calcium channels by patch-clamp recordings and calcium imaging analysis of TCs from pregnant human myometrium by perfusing with BAY K8644, which induced calcium influx through these channels. Additionally, we demonstrated that beta-estradiol (1000 nM) antagonized the effect of BAY K8644 (2.5 or 5 µM) in the same preparations. In conclusion, we evidenced the presence of voltage-gated calcium channels and estrogen receptors in TCs from non-pregnant and pregnant human

  20. A biomimetic approach to the detection and identification of estrogen receptor agonists in surface waters using semipermeable membrane devices (SPMDs) and bioassay-directed chemical analysis.

    PubMed

    Rastall, Andrew C; Getting, Dominic; Goddard, Jon; Roberts, David R; Erdinger, Lothar

    2006-07-01

    Some anthropogenic pollutants posses the capacity to disrupt endogenous control of developmental and reproductive processes in aquatic biota by activating estrogen receptors. Many anthropogenic estrogen receptor agonists (ERAs) are hydrophobic and will therefore readily partition into the abiotic organic carbon phases present in natural waters. This partitioning process effectively reduces the proportion of ERAs readily available for bioconcentration by aquatic biota. Results from some studies have suggested that for many aquatic species, bioconcentration of the freely-dissolved fraction may be the principal route of uptake for hydrophobic pollutants with logarithm n-octanol/water partition coefficient (log Kow) values less than approximately 6.0, which includes the majority of known anthropogenic ERAs. The detection and identification of freely-dissolved readily bioconcentratable ERAs is therefore an important aspect of exposure and risk assessment. However, most studies use conventional techniques to sample total ERA concentrations and in doing so frequently fail to account for bioconcentration of the freely-dissolved fraction. The aim of the current study was to couple the biomimetic sampling properties of semipermeable membrane devices (SPMDs) to a bioassay-directed chemical analysis (BDCA) scheme for the detection and identification of readily bioconcentratable ERAs in surface waters. SPMDs were constructed and deployed at a number of sites in Germany and the UK. Following the dialytic recovery of target compounds and size exclusion chromatographic cleanup, SPMD samples were fractionated using a reverse-phase HPLC method calibrated to provide an estimation of target analyte log Kow. A portion of each HPLC fraction was then subjected to the yeast estrogen screen (YES) to determine estrogenic potential. Results were plotted in the form of 'estrograms' which displayed profiles of estrogenic potential as a function of HPLC retention time (i.e. hydrophobicity) for

  1. Localization and Divergent Profiles of Estrogen Receptors and Aromatase in the Vocal and Auditory Networks of a Fish with Alternative Mating Tactics

    PubMed Central

    Fergus, Daniel J.; Bass, Andrew H.

    2013-01-01

    Estrogens play a salient role in the development and maintenance of both male and female nervous systems and behaviors. The plainfin midshipman (Porichthys notatus), a teleost fish, has two male reproductive morphs that follow alternative mating tactics and diverge in multiple somatic, hormonal and neural traits, including the central control of morph-specific vocal behaviors. After we identified duplicate estrogen receptors (ERβ1 and ERβ2) in midshipman, we developed antibodies to localize protein expression in the central vocal-acoustic networks and saccule, the auditory division of the inner ear. As in other teleost species, ERβ1 and ERβ2 were robustly expressed in the telencephalon and hypothalamus in vocal-acoustic and other brain regions shown previously to exhibit strong expression of ERα and aromatase (estrogen synthetase, CYP19) in midshipman. Like aromatase, ERβ1 label co-localized with glial fibrillary acidic protein (GFAP) in telencephalic radial glial cells. Quantitative PCR revealed similar patterns of transcript abundance across reproductive morphs for ERβ1, ERβ2, ERα and aromatase in the forebrain and saccule. In contrast, transcript abundance for ERs and aromatase varied significantly between morphs in and around the sexually polymorphic vocal motor nucleus (VMN). Together, the results suggest that VMN is the major estrogen target within the estrogen-sensitive hindbrain vocal network that directly determines the duration, frequency and amplitude of morph-specific vocalizations. Comparable regional differences in steroid receptor abundances likely regulate morph-specific behaviors in males and females of other species exhibiting alternative reproductive tactics. PMID:23460422

  2. The sexually dimorphic role of adipose and adipocyte estrogen receptors in modulating adipose tissue expansion, inflammation, and fibrosis

    PubMed Central

    Davis, Kathryn E.; D. Neinast, Michael; Sun, Kai; M. Skiles, William; D. Bills, Jessica; A. Zehr, Jordan; Zeve, Daniel; D. Hahner, Lisa; W. Cox, Derek; M. Gent, Lana; Xu, Yong; V. Wang, Zhao; A. Khan, Sohaib; Clegg, Deborah J.

    2013-01-01

    Our data demonstrate that estrogens, estrogen receptor-α (ERα), and estrogen receptor-β (ERβ) regulate adipose tissue distribution, inflammation, fibrosis, and glucose homeostasis, by determining that αERKO mice have increased adipose tissue inflammation and fibrosis prior to obesity onset. Selective deletion of adipose tissue ERα in adult mice using a novel viral vector technology recapitulated the findings in the total body ERα null mice. Generation of a novel mouse model, lacking ERα specifically from adipocytes (AdipoERα), demonstrated increased markers of fibrosis and inflammation, especially in the males. Additionally, we found that the beneficial effects of estrogens on adipose tissue require adipocyte ERα. Lastly, we determined the role of ERβ in regulating inflammation and fibrosis, by breeding the AdipoERα into the βERKO background and found that in the absence of adipocyte ERα, ERβ has a protective role. These data suggest that adipose tissue and adipocyte ERα protects against adiposity, inflammation, and fibrosis in both males and females. PMID:24049737

  3. In vivo functions of GPR30/GPER-1, a membrane receptor for estrogen: from discovery to functions in vivo.

    PubMed

    Mizukami, Yoichi

    2010-01-01

    G protein-coupled receptor 30/G protein-coupled estrogen receptor-1 (GPR30/GPER-1) was reported as a novel membrane receptor for estrogen in 2005. However, the research on GPR30 has produced conflicting reports with regard to its intracellular localization, the tissue distribution of its expression, and some its functions. Recently, in addition to the finding of G-1, a GPR30 agonist, GPR30 KO mice have been produced in laboratories, and this has significantly increased the confidence in the data. In this review, the intrinsic appearance of GPR30 is approached based mainly on data obtained in vivo.

  4. CDNA CLONING OF FATHEAD MINNOW (PIMEPHALES PROMELAS) ESTROGEN AND ANDROGEN RECEPTORS FOR USE IN STEROID RECEPTOR EXTRAPOLATION STUDIES FOR ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    cDNA Cloning of Fathead minnow (Pimephales promelas) Estrogen and Androgen Receptors for Use in Steroid Receptor Extrapolation Studies for Endocrine Disrupting Chemicals.

    Wilson, V.S.1,, Korte, J.2, Hartig P. 1, Ankley, G.T.2, Gray, L.E., Jr 1, , and Welch, J.E.1. 1U.S...

  5. Human Endometriosis Tissue Microarray Reveals Site-specific Expression of Estrogen Receptors, Progesterone Receptor, and Ki67.

    PubMed

    Colón-Caraballo, Mariano; García, Miosotis; Mendoza, Adalberto; Flores, Idhaliz

    2018-04-07

    Most available therapies for endometriosis are hormone-based and generally broadly used without taking into consideration the ovarian hormone receptor expression status. This contrasts strikingly with the standard of care for other hormone-based conditions such as breast cancer. We therefore aimed to characterize the expression of ovarian steroid hormone receptors for estrogen alpha (ESR1), estrogen beta (ESR2), and progesterone (PGR) in different types of endometriotic lesions and eutopic endometrium from women with endometriosis and controls using a tissue microarray (TMA). Nuclear expression levels of the receptors were analyzed by tissue (ie, ectopic vs. eutopic endometrium) and cell type (ie, glands vs. stroma). Ovarian lesions showed the lowest expression of ESR1 and PGR, and the highest expression of ESR2, whereas the fallopian tube lesions showed high expression of the 3 receptors. Differences among endometria included lower expression of ESR1 and higher expression of ESR2 in stroma of proliferative endometrium from patients versus patients, and a trend towards loss of PGR nuclear positivity in proliferative endometrium from patients. The largest ESR2:ESR1 ratios were observed in ovarian lesions and secretory endometrium. The highest proportion of samples with >10% Ki67 positive nuclei was in glands of fallopian tube (54%) and extrapelvic lesions (75%); 60% of glands of secretory endometrium from patients had >10% Ki67 positivity compared with only 15% in controls. Our results provide a better understanding of endometriosis heterogeneity by revealing lesion type-specific differences and case-by-case variability in the expression of ovarian hormone receptors. This knowledge could potentially predict individual responses to hormone therapies, and set the basis for the application of personalized medicine approaches for women with endometriosis.

  6. Estrogen and Thyroid Hormone Receptor Activation by Medicinal Plants from Bahia, Brazil

    PubMed Central

    da Silva, Magnus Régios Dias; Costa, Silvia Lima; Velozo, Eudes da Silva

    2018-01-01

    Background: A number of medicinal plants are traditionally used for metabolic disorders in Bahia state, Brazil. The aim of this study was to evaluate the estrogen receptor (ER) and thyroid receptor (TR) activation of crude extracts prepared from 20 plants. Methods: Species were extracted and assayed for receptor activation through both ER and TR gene-reporter assays, using 17β-estradiol and triiodothyronine (T3), respectively, as the positive controls. Results: Cajanus cajan (Fabaceae), Abarema cochliacarpus (Fabaceae), and Borreria verticillata (Rubiaceae) were able to activate ER as much as the positive control (17β-estradiol). These three plant species were also assayed for TR activation. At the concentration of 50 µg/mL, C. cajans exerted the highest positive modulation on TR, causing an activation of 59.9%, while B. verticillata and A. cochliacarpus caused 30.8% and 23.3%, respectively. Conclusions: Our results contribute towards the validation of the traditional use of C. cajans, B. verticillata, and A. cochliacarpus in the treatment of metabolic disorders related to ER and TR functions. The gene-reporter assay was proven effective in screening crude plant extracts for ER/TR activation, endorsing this methodology as an important tool for future bioprospection studies focused on identifying novel starting molecules for the development of estrogen and thyroid agonists. PMID:29342924

  7. Stanniocalcin 2 is an estrogen-responsive gene coexpressed with the estrogen receptor in human breast cancer.

    PubMed

    Bouras, Toula; Southey, Melissa C; Chang, Andy C; Reddel, Roger R; Willhite, Dorian; Glynne, Richard; Henderson, Michael A; Armes, Jane E; Venter, Deon J

    2002-03-01

    Differences in gene expression are likely to explain the phenotypic variation between hormone-responsive and hormone-unresponsive breast cancers. In this study, DNA microarray analysis of approximately 10,000 known genes and 25,000 expressed sequence tag clusters was performed to identify genes induced by estrogen and repressed by the pure antiestrogen ICI 182 780 in vitro that correlated with estrogen receptor (ER) expression in primary breast carcinomas in vivo. Stanniocalcin (STC) 2 was identified as one of the genes that fulfilled these criteria. DNA microarray hybridization showed a 3-fold induction of STC2 mRNA expression in MCF-7 cells in < or = 3 h of estrogen exposure and a 3-fold repression in the presence of antiestrogen (one-way ANOVA, P < 0.0005). In 13 ER-positive and 12 ER-negative breast carcinomas, the microarray-derived mRNA levels observed for STC2 correlated with tumor ER mRNA (Pearson's correlation, r = 0.85; P < 0.0001) and ER protein status (Spearman's rank correlation, r = 0.73; P < 0.0001). The expression profile of STC2 was further confirmed by in situ hybridization and immunohistochemistry on a larger cohort of 236 unselected breast carcinomas using tissue microarrays. STC2 mRNA and protein expression were found to be associated with tumor ER status (Fisher's exact test, P < 0.005). The related gene, STC1, was also examined and shown to be associated with ER status in breast carcinomas (Fisher's exact test, P < 0.05). This study demonstrates the feasibility of using global gene expression data derived from an in vitro model to pinpoint novel estrogen-responsive genes of potential clinical relevance.

  8. Black tea and D. candidum extracts play estrogenic activity via estrogen receptor α-dependent signaling pathway

    PubMed Central

    Wang, Yongsen; Sun, Jing; Zhang, Kun; Hu, Xin; Sun, Yuchu; Sheng, Jun; Fu, Xueqi

    2018-01-01

    In recent years, phytoestrogens have been shown as useful selective estrogen receptor modulators. The estrogen-like effects of black tea (BT) and D. candidum (DC), as well as the combination of the two herbs, have remained largely elusive. This study aims to investigate the phytoestrogenic effect of BT and DC extract, and the possible mechanism. The effects on T47D (ER+ cell line) proliferation were evaluated by using MTT assay. The S phase proportion of ER+ cells was determined by using flow cytometry. The estrogen antagonist ICI 182,780 was applied to block the ER function. The activation of ER-mediated PI3K/AKT and ERK signal pathways were observed by using western blot. Expression of ERα and PGR, as well as PS2 and Cyclin D1 were detected by using western blot and real-time quantitative PCR. Firstly, our results found that BT and DC extracts promoted cell proliferation in ER-positive cells, and this effect was ER-dependent. Besides, BT and DC extracts increased the S-phase cell number. Next, PI3K, AKT and ERK pathways below ER were activated by phytoestrogen treatment, and this activation was blocked by the ER antagonist. Moreover, prolonged BT and DC treatments increased the expression of ESR1 and PGR. Consistently, the mRNA levels of not only ESR1 and PGR but also estrogen-dependent effectors ps2 and cyclin D1, were increased by phytoestrogens and blocked by ICI 182,780. Taken Together, BT and DC extracts have phytoestrogenic effects, and this may provide new ideas and experimental basis for the development and application of phytoestrogens. PMID:29422998

  9. Effect of protracted estrogen administration on the thyroid of Ames dwarf mice.

    PubMed

    Vidal, S; Cameselle-Teijeiro, J; Horvath, E; Kovacs, K; Bartke, A

    2001-04-01

    The effect of protracted estrogen administration on estrogen receptor expression and cellular composition of the thyroid was examined in genetically thyrotropin (TSH)-deficient female Ames dwarf mice (df/df) to reveal whether estrogen might act independently from TSH. inducing changes in thyroid morphology and function. To evaluate such changes, the thyroid from four estrogen-implanted Ames dwarf mice, four sham-implanted Ames dwarf mice and four sham-implanted normal littermate mice were investigated histologically, immunohistochemically and morphometrically. Our morphologic study demonstrated significant differences in the colloid areas of normal and dwarf mice (P<0.001). The correlation observed between this parameter and body weights (r=0.610, P<0.05) and thyroid weights (r=0.729, P<0.01) suggests that the decrease in the colloid areas is not a result of abnormal folliculogenesis but is in direct correlation with the small thyroid and body size of dwarf mice. Although two types of estrogen receptors are known to exist in the present study, only the alpha (ERalpha) variant was found in the thyroid. ERalpha immunoreactivity was detected in the nuclei of parafollicular cells but not of the follicular epithelium. No significant differences were reported in ER expression between estrogen-implanted dwarf mice and sham-implanted dwarf mice, suggesting that estrogen receptor expression in the thyroid is independent of circulating estrogen levels. In spite of the absence of ERalpha in follicular cells, protracted estrogen administration affected mainly the follicular cells. Our results suggest that when TSH is absent estrogens may exert a negative feedback on the activity of follicular cells.

  10. Estrogens in Male Physiology.

    PubMed

    Cooke, Paul S; Nanjappa, Manjunatha K; Ko, CheMyong; Prins, Gail S; Hess, Rex A

    2017-07-01

    Estrogens have historically been associated with female reproduction, but work over the last two decades established that estrogens and their main nuclear receptors (ESR1 and ESR2) and G protein-coupled estrogen receptor (GPER) also regulate male reproductive and nonreproductive organs. 17β-Estradiol (E2) is measureable in blood of men and males of other species, but in rete testis fluids, E2 reaches concentrations normally found only in females and in some species nanomolar concentrations of estrone sulfate are found in semen. Aromatase, which converts androgens to estrogens, is expressed in Leydig cells, seminiferous epithelium, and other male organs. Early studies showed E2 binding in numerous male tissues, and ESR1 and ESR2 each show unique distributions and actions in males. Exogenous estrogen treatment produced male reproductive pathologies in laboratory animals and men, especially during development, and studies with transgenic mice with compromised estrogen signaling demonstrated an E2 role in normal male physiology. Efferent ductules and epididymal functions are dependent on estrogen signaling through ESR1, whose loss impaired ion transport and water reabsorption, resulting in abnormal sperm. Loss of ESR1 or aromatase also produces effects on nonreproductive targets such as brain, adipose, skeletal muscle, bone, cardiovascular, and immune tissues. Expression of GPER is extensive in male tracts, suggesting a possible role for E2 signaling through this receptor in male reproduction. Recent evidence also indicates that membrane ESR1 has critical roles in male reproduction. Thus estrogens are important physiological regulators in males, and future studies may reveal additional roles for estrogen signaling in various target tissues. Copyright © 2017 the American Physiological Society.

  11. Estrogen receptor (ER) and progesterone receptor (PgR) in breast cancer of Indian women

    PubMed Central

    Patil, Amit V; Bhamre, Rahul S; Singhai, Rajeev; Tayade, Mukund B; Patil, Vinayak W

    2011-01-01

    Objective To determine the expressions and relationship between estrogen receptors (ERs) and progesterone receptors (PgRs) in breast cancer in Indian women. Participants Surgically removed breast cancer tissues were collected from Grant Medical College and Sir JJ Group of Hospitals, Mumbai, India, taking (n = 300) cases of infiltrating duct cancer of Indian women after radical mastectomy and lumpectomy; the age- and menopausal-related subgroups satisfied this requirement. Measurements Statistical significance was calculated by the likelihood ratio test; relative risk served to check for significant differences. Relapse-free interval probabilities were calculated according to Kaplan and Meier, with Cox–Mantel test comparing survival functions and P values. Results We observed that only in middle-aged postmenopausal patients bearing pT2 tumors were ER and PgR receptors shown to have a prognostic significance with the lowest tested cutoff value being 5 fmol/mg. Conclusion Immunohistochemistry analysis has been shown to be a prognostic factor for patients with breast cancer; the major aim of determining the ER receptor status is to assess predictive response to hormonal therapy. PMID:24367174

  12. Expression and subcellular localization of estrogen receptors α and β in human fetal brown adipose tissue.

    PubMed

    Velickovic, Ksenija; Cvoro, Aleksandra; Srdic, Biljana; Stokic, Edita; Markelic, Milica; Golic, Igor; Otasevic, Vesna; Stancic, Ana; Jankovic, Aleksandra; Vucetic, Milica; Buzadzic, Biljana; Korac, Bato; Korac, Aleksandra

    2014-01-01

    Brown adipose tissue (BAT) has the unique ability of generating heat due to the expression of mitochondrial uncoupling protein 1 (UCP1). A recent discovery regarding functional BAT in adult humans has increased interest in the molecular pathways of BAT development and functionality. An important role for estrogen in white adipose tissue was shown, but the possible role of estrogen in human fetal BAT (fBAT) is unclear. The objective of this study was to determine whether human fBAT expresses estrogen receptor α (ERα) and ERβ. In addition, we examined their localization as well as their correlation with crucial proteins involved in BAT differentiation, proliferation, mitochondriogenesis and thermogenesis including peroxisome proliferator-activated receptor γ (PPARγ), proliferating cell nuclear antigen (PCNA), PPARγ-coactivator-1α (PGC-1α), and UCP1. The fBAT was obtained from 4 human male fetuses aged 15, 17, 20, and 23 weeks gestation. ERα and ERβ expression was assessed using Western blotting, immunohistochemistry, and immunocytochemistry. Possible correlations with PPARγ, PCNA, PGC-1α, and UCP1 were examined by double immunofluorescence. Both ERα and ERβ were expressed in human fBAT, with ERα being dominant. Unlike ERβ, which was present only in mature brown adipocytes, we detected ERα in mature adipocytes, preadipocytes, mesenchymal and endothelial cells. In addition, double immunofluorescence supported the notion that differentiation in fBAT probably involves ERα. Immunocytochemical analysis revealed mitochondrial localization of both receptors. The expression of both ERα and ERβ in human fBAT suggests a role for estrogen in its development, primarily via ERα. In addition, our results indicate that fBAT mitochondria could be targeted by estrogens and pointed out the possible role of both ERs in mitochondriogenesis.

  13. GPER-1 and estrogen receptor-β ligands modulate aldosterone synthesis.

    PubMed

    Caroccia, Brasilina; Seccia, Teresa M; Campos, Abril Gonzalez; Gioco, Francesca; Kuppusamy, Maniselvan; Ceolotto, Giulio; Guerzoni, Eugenia; Simonato, Francesca; Mareso, Sara; Lenzini, Livia; Fassina, Ambrogio; Rossi, Gian Paolo

    2014-11-01

    Fertile women have lower blood pressure and cardiovascular risk than age-matched men, which suggests that estrogens exert cardiovascular protective effects. However, whether 17 β-estradiol (E2) blunts aldosterone secretion, and thereby affects the gender dimorphism of blood pressure, is unknown. We therefore sought for the estrogen receptor (ER) subtypes in human adrenocortical tissues ex vivo by performing gene and protein expression studies. We also investigated the effect of E2 on aldosterone synthesis and the involved receptors through in vitro functional experiments in the adrenocortical cells HAC15. We found that in the human adrenal cortex and aldosterone-producing adenoma cells, the most expressed ERs were the ERβ and the G protein-coupled receptor-1 (GPER-1), respectively. After selective ERβ blockade, E2 (10 nmol/L) markedly increased both the expression of aldosterone synthase and the production of aldosterone (+5- to 7-fold vs baseline, P < .001). Under the same condition, the GPER-1 receptor agonist 1-[4-(6-bromo-benzo (1, 3)dioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c] quinolin-8-yl]-ethanone (G-1) (10 nmol/L) mimicked this effect, which was abrogated by cotreatment with either the GPER-1 receptor antagonist (3aS*,4R*,9bR*)-4-(6-Bro-mo-1,3-benzodioxol-5-yl)-3a,4,5,9b-3H-cyclopenta[c]quinoline (G-15), or a selective protein kinase A inhibitor 8-Bromo-2-monobutyryladenosine-3,5-cyclic mono-phosphorothioate, Rp-isomer. Silencing of the ERβ significantly raised aldosterone synthase expression and aldosterone production. Conversely, silencing of the GPER-1 lowered aldosterone synthase gene and protein expression. Moreover, it blunted the stimulatory effect of E2 on aldosterone synthase that was seen during ERβ blockade. These results support the conclusion that in humans, E2 inhibits aldosterone synthesis by acting via ERβ. Pharmacologic disinhibition of ERβ unmasks a potent secretagogue effect of E2 that involves GPER-1 and protein kinase A

  14. Association with replication between estrogen-related receptor gamma (ESRRgamma) polymorphisms and bone phenotypes in women of European ancestry.

    PubMed

    Elfassihi, Latifa; Giroux, Sylvie; Bureau, Alexandre; Laflamme, Nathalie; Cole, David Ec; Rousseau, François

    2010-04-01

    Osteoporosis is a bone disease characterized by low bone mineral density (BMD), a highly heritable polygenic trait. Women are more prone than men to develop osteoporosis owing to a lower peak bone mass and accelerated bone loss at menopause. Lack of estrogen thus is a major risk factor for osteoporosis. In addition to having strong similarity to the estrogen receptor 1 (ESR1), the orphan nuclear estrogen-related receptor gamma (ESRRgamma) is widely expressed and shows overlap with ESR1 expression in tissues where estrogen has important physiologic functions. For these reasons, we have undertaken a study of ESRRgamma sequence variants in association with bone measurements [heel quantitative ultrasound (QUS) by measurements of broadband ultrasound attenuation (BUA), speed of sound (SOS), and stiffness index (SI) and dual-energy X-ray absorptiometry (DXA) at the femoral neck (FN) and lumbar spine (LS)]. A silent variant was found to be associated with multiple bone measurements (LS, BUA, SOS, and SI), the p values ranging from .006 to .04 in a sample of 5144 Quebec women. The region of this variant was analyzed using the HapMap database and the Gabriel method to define a block of 20 kb. Using the Tagger method, eight TagSNPs were identified and genotyped in a sample of 1335 women. Four of these SNPs capture the five major block haplotypes. One SNP (rs2818964) and one haplotype were significantly associated with multiple bone measures. All SNPs involved in the associations were analyzed in two other sample sets with significant results in the same direction. These results suggest involvement of ESRRgamma in the determination of bone density in women. Copyright 2010 American Society for Bone and Mineral Research.

  15. Female Mice Lacking Estrogen Receptor-α in Hypothalamic Proopiomelanocortin (POMC) Neurons Display Enhanced Estrogenic Response on Cortical Bone Mass.

    PubMed

    Farman, H H; Windahl, S H; Westberg, L; Isaksson, H; Egecioglu, E; Schele, E; Ryberg, H; Jansson, J O; Tuukkanen, J; Koskela, A; Xie, S K; Hahner, L; Zehr, J; Clegg, D J; Lagerquist, M K; Ohlsson, C

    2016-08-01

    Estrogens are important regulators of bone mass and their effects are mainly mediated via estrogen receptor (ER)α. Central ERα exerts an inhibitory role on bone mass. ERα is highly expressed in the arcuate (ARC) and the ventromedial (VMN) nuclei in the hypothalamus. To test whether ERα in proopiomelanocortin (POMC) neurons, located in ARC, is involved in the regulation of bone mass, we used mice lacking ERα expression specifically in POMC neurons (POMC-ERα(-/-)). Female POMC-ERα(-/-) and control mice were ovariectomized (OVX) and treated with vehicle or estradiol (0.5 μg/d) for 6 weeks. As expected, estradiol treatment increased the cortical bone thickness in femur, the cortical bone mechanical strength in tibia and the trabecular bone volume fraction in both femur and vertebrae in OVX control mice. Importantly, the estrogenic responses were substantially increased in OVX POMC-ERα(-/-) mice compared with the estrogenic responses in OVX control mice for cortical bone thickness (+126 ± 34%, P < .01) and mechanical strength (+193 ± 38%, P < .01). To test whether ERα in VMN is involved in the regulation of bone mass, ERα was silenced using an adeno-associated viral vector. Silencing of ERα in hypothalamic VMN resulted in unchanged bone mass. In conclusion, mice lacking ERα in POMC neurons display enhanced estrogenic response on cortical bone mass and mechanical strength. We propose that the balance between inhibitory effects of central ERα activity in hypothalamic POMC neurons in ARC and stimulatory peripheral ERα-mediated effects in bone determines cortical bone mass in female mice.

  16. Calmodulin-like protein 3 is an estrogen receptor alpha coregulator for gene expression and drug response in a SNP, estrogen, and SERM-dependent fashion.

    PubMed

    Qin, Sisi; Ingle, James N; Liu, Mohan; Yu, Jia; Wickerham, D Lawrence; Kubo, Michiaki; Weinshilboum, Richard M; Wang, Liewei

    2017-08-18

    We previously performed a case-control genome-wide association study in women treated with selective estrogen receptor modulators (SERMs) for breast cancer prevention and identified single nucleotide polymorphisms (SNPs) in ZNF423 as potential biomarkers for response to SERM therapy. The ZNF423rs9940645 SNP, which is approximately 200 bp away from the estrogen response elements, resulted in the SNP, estrogen, and SERM-dependent regulation of ZNF423 expression and, "downstream", that of BRCA1. Electrophoretic mobility shift assay-mass spectrometry was performed to identify proteins binding to the ZNF423 SNP and coordinating with estrogen receptor alpha (ERα). Clustered, regularly interspaced short palindromic repeats (CRISPR)/Cas9 genome editing was applied to generate ZR75-1 breast cancer cells with different ZNF423 SNP genotypes. Both cultured cells and mouse xenograft models with different ZNF423 SNP genotypes were used to study the cellular responses to SERMs and poly(ADP-ribose) polymerase (PARP) inhibitors. We identified calmodulin-like protein 3 (CALML3) as a key sensor of this SNP and a coregulator of ERα, which contributes to differential gene transcription regulation in an estrogen and SERM-dependent fashion. Furthermore, using CRISPR/Cas9-engineered ZR75-1 breast cancer cells with different ZNF423 SNP genotypes, striking differences in cellular responses to SERMs and PARP inhibitors, alone or in combination, were observed not only in cells but also in a mouse xenograft model. Our results have demonstrated the mechanism by which the ZNF423 rs9940645 SNP might regulate gene expression and drug response as well as its potential role in achieving more highly individualized breast cancer therapy.

  17. GPR30 and estrogen receptor expression: new insights into hormone dependence of inflammatory breast cancer.

    PubMed

    Arias-Pulido, Hugo; Royce, Melanie; Gong, Yun; Joste, Nancy; Lomo, Lesley; Lee, Sang-Joon; Chaher, Nabila; Verschraegen, Claire; Lara, Juanita; Prossnitz, Eric R; Cristofanilli, Massimo

    2010-08-01

    GPR30 is a novel G protein-coupled estrogen receptor (ER) associated with metastases in breast cancer (BC) and poor survival in endometrial and ovarian tumors. The association of GPR30 expression with inflammatory breast cancer (IBC), an aggressive and commonly hormone-independent form of BC, has not been studied. GPR30, ER, progesterone receptor (PR), epidermal growth factor receptor (EGFR), and HER-2 expression were assessed by immunohistochemistry (and FISH for HER-2) in 88 primary IBCs. GPR30 expression was correlated with patient overall survival (OS), disease-free survival (DFS), pathologic variables, and other biomarkers. GPR30 expression was found in 69% of IBC cases. ER, PR, HER-2, and EGFR were found in 43, 35, 39, and 34% of IBC cases, respectively. GPR30 expression correlated inversely with ER expression (P = 0.02). Co-expression of ER and GPR30 was found in 24% of IBC samples; 19% expressed only ER and 46% expressed only GPR30. Univariate analysis showed no association between GPR30 expression and OS or DFS. However, co-expression of ER and GPR30 was associated with improved OS (P < 0.03) and marginally with DFS (P < 0.06); the absence of both ER and GPR30 was associated with worse OS and DFS (P = 0.03 for both). Multivariate analysis identified ER as an independent prognostic factor of OS (P = 0.008) and DFS (P = 0.02). The majority of IBC tumors are GPR30-positive, suggesting that estrogen signaling may be active in ER-negative IBC patients. These findings suggest potential new therapeutic targets for IBC such as novel endocrine agents or direct modulation of GPR30.

  18. Sexual Dimorphism and Estrogen Action in Mouse Liver.

    PubMed

    Torre, Della; Lolli, Federica; Ciana, Paolo; Maggi, Adriana

    2017-01-01

    Recent studies have demonstrated that in mice, the estrogen receptor alpha (ERα) is expressed in the liver and has a direct effect on the regulation of the hepatic genes relevant for energy metabolism and drug metabolism. The sex-related differential expression of the hepatic ERα raises the questions as to whether this receptor is responsible for the sexual differences observed in the physiopathology of the liver.

  19. Thiophene-Core Estrogen Receptor Ligands Having Superagonist Activity

    PubMed Central

    Min, Jian; Wang, Pengcheng; Srinivasan, Sathish; Nwachukwu, Jerome C.; Guo, Pu; Huang, Minjian; Carlson, Kathryn E.; Katzenellenbogen, John A.; Nettles, Kendall W.; Zhou, Hai-Bing

    2013-01-01

    To probe the importance of the heterocyclic core of estrogen receptor (ER) ligands, we prepared a series of thiophene-core ligands by Suzuki cross-coupling of aryl boronic acids with bromo-thiophenes, and we assessed their receptor binding and cell biological activities. The disposition of the phenol substituents on the thiophene core, at alternate or adjacent sites, and the nature of substituents on these phenols all contribute to binding affinity and subtype selectivity. Most of the bis(hydroxyphenyl)-thiophenes were ERβ selective, whereas the tris(hydroxyphenyl)-thiophenes were ERα selective; analogous furan-core compounds generally have lower affinity and less selectivity. Some diarylthiophenes show distinct superagonist activity in reporter gene assays, giving maximal activities 2–3 times that of estradiol, and modeling suggests that these ligands have a different interaction with a hydrogen-bonding residue in helix-11. Ligand-core modification may be a new strategy for developing ER ligands whose selectivity is based on having transcriptional activity greater than that of estradiol. PMID:23586645

  20. Maternal Regulation of Estrogen Receptor α Methylation

    PubMed Central

    Champagne, Frances A.; Curley, James P.

    2008-01-01

    Summary Advances in molecular biology have provided tools for studying the epigenetic factors which modulate gene expression. DNA methylation is an epigenetic modification which can have sustained effects on transcription and is associated with long-term gene silencing. In this review, we focus on the regulation of estrogen receptor alpha (ERα) expression by hormonal and environmental cues, the consequences of these cues for female maternal and sexual behavior and recent studies which explore the role of DNA methylation in mediating these developmental effects, with particular focus on the mediating role of maternal care. The methylation status of ERα has implications for reproductive behavior, cancer susceptibility and recovery from ischemic injury suggesting an epigenetic basis for risk and resilience across the life span. PMID:18644464

  1. Nature of the binding interaction for 50 structurally diverse chemicals with rat estrogen receptors

    EPA Science Inventory

    This study was conducted to characterize the estrogen receptor (ER)-binding affinities of 50 chemicals selected from among the high production volume chemicals under the U.S. EPA's (U.S. Environmental Protection Agency's) Toxic Substances Control Act inventory. The chemicals were...

  2. Activation of the novel estrogen receptor G protein-coupled receptor 30 (GPR30) at the plasma membrane.

    PubMed

    Filardo, E; Quinn, J; Pang, Y; Graeber, C; Shaw, S; Dong, J; Thomas, P

    2007-07-01

    G protein-coupled receptor 30 (GPR30), a seven-transmembrane receptor (7TMR), is associated with rapid estrogen-dependent, G protein signaling and specific estrogen binding. At present, the subcellular site of GPR30 action is unclear. Previous studies using antibodies and fluorochrome-labeled estradiol (E2) have failed to detect GPR30 on the cell surface, suggesting that GPR30 may function uniquely among 7TMRs as an intracellular receptor. Here, we show that detectable expression of GPR30 on the surface of transfected HEK-293 cells can be selected by fluorescence-activated cell sorting. Expression of GPR30 on the cell surface was confirmed by confocal microscopy using the lectin concanavalin A as a plasma membrane marker. Stimulation of GPR30-expressing HEK-293 cells with 17beta-E2 caused sequestration of GPR30 from the cell surface and resulted in its codistribution with clathrin and mobilization of intracellular calcium stores. Evidence that GPR30 signals from the cell surface was obtained from experiments demonstrating that the cell-impermeable E2-protein conjugates E2-BSA and E2-horseradish peroxidase promote GPR30-dependent elevation of intracellular cAMP concentrations. Subcellular fractionation studies further support the plasma membrane as a site of GPR30 action with specific [3H]17beta-E2 binding and G protein activation associated with plasma membrane but not microsomal, or other fractions, prepared from HEK-293 or SKBR3 breast cancer cells. These results suggest that GPR30, like other 7TMRs, functions as a plasma membrane receptor.

  3. Immune-Specific Expression and Estrogenic Regulation of the Four Estrogen Receptor Isoforms in Female Rainbow Trout (Oncorhynchus mykiss).

    PubMed

    Casanova-Nakayama, Ayako; Wernicke von Siebenthal, Elena; Kropf, Christian; Oldenberg, Elisabeth; Segner, Helmut

    2018-03-21

    Genomic actions of estrogens in vertebrates are exerted via two intracellular estrogen receptor (ER) subtypes, ERα and ERβ, which show cell- and tissue-specific expression profiles. Mammalian immune cells express ERs and are responsive to estrogens. More recently, evidence became available that ERs are also present in the immune organs and cells of teleost fish, suggesting that the immunomodulatory function of estrogens has been conserved throughout vertebrate evolution. For a better understanding of the sensitivity and the responsiveness of the fish immune system to estrogens, more insight is needed on the abundance of ERs in the fish immune system, the cellular ratios of the ER subtypes, and their autoregulation by estrogens. Consequently, the aims of the present study were (i) to determine the absolute mRNA copy numbers of the four ER isoforms in the immune organs and cells of rainbow trout, Oncorhynchus mykiss , and to compare them to the hepatic ER numbers; (ii) to analyse the ER mRNA isoform ratios in the immune system; and, (iii) finally, to examine the alterations of immune ER mRNA expression levels in sexually immature trout exposed to 17β-estradiol (E2), as well as the alterations of immune ER mRNA expression levels in sexually mature trout during the reproductive cycle. All four ER isoforms were present in immune organs-head kidney, spleen-and immune cells from head kidney and blood of rainbow trout, but their mRNA levels were substantially lower than in the liver. The ER isoform ratios were tissue- and cell-specific, both within the immune system, but also between the immune system and the liver. Short-term administration of E2 to juvenile female trout altered the ER mRNA levels in the liver, but the ERs of the immune organs and cells were not responsive. Changes of ER gene transcript numbers in immune organs and cells occurred during the reproductive cycle of mature female trout, but the changes in the immune ER profiles differed from those in the

  4. 17β-Estradiol and Agonism of G-protein-Coupled Estrogen Receptor Enhance Hippocampal Memory via Different Cell-Signaling Mechanisms.

    PubMed

    Kim, Jaekyoon; Szinte, Julia S; Boulware, Marissa I; Frick, Karyn M

    2016-03-16

    The ability of 17β-estradiol (E2) to enhance hippocampal object recognition and spatial memory depends on rapid activation of extracellular signal-regulated kinase (ERK) in the dorsal hippocampus (DH). Although this activation can be mediated by the intracellular estrogen receptors ERα and ERβ, little is known about the role that the membrane estrogen receptor GPER plays in regulating ERK or E2-mediated memory formation. In this study, post-training DH infusion of the GPER agonist G-1 enhanced object recognition and spatial memory in ovariectomized female mice, whereas the GPER antagonist G-15 impaired memory, suggesting that GPER activation, like E2, promotes hippocampal memory formation. However, unlike E2, G-1 did not increase ERK phosphorylation, but instead significantly increased phosphorylation of c-Jun N-terminal kinase (JNK) in the DH. Moreover, DH infusion of the JNK inhibitor SP600125 prevented G-1 from enhancing object recognition and spatial memory, but the ERK inhibitor U0126 did not. These data suggest that GPER enhances memory via different cell-signaling mechanisms than E2. This conclusion was supported by data showing that the ability of E2 to facilitate memory and activate ERK signaling was not blocked by G-15 or SP600125, which demonstrates that the memory-enhancing effects of E2 are not dependent on JNK or GPER activation in the DH. Together, these data indicate that GPER regulates memory independently from ERα and ERβ by activating JNK signaling, rather than ERK signaling. Thus, the findings suggest that GPER in the DH may not function as an estrogen receptor to regulate object recognition and spatial memory. Although 17β-estradiol has long been known to regulate memory function, the molecular mechanisms underlying estrogenic memory modulation remain largely unknown. Here, we examined whether the putative membrane estrogen receptor GPER acts like the classical estrogen receptors, ERα and ERβ, to facilitate hippocampal memory in female

  5. Involvement of estrogen receptor alpha, beta and oxytocin in social discrimination: A detailed behavioral analysis with knockout female mice.

    PubMed

    Choleris, E; Ogawa, S; Kavaliers, M; Gustafsson, J-A; Korach, K S; Muglia, L J; Pfaff, D W

    2006-10-01

    Social recognition, processing, and retaining information about conspecific individuals is crucial for the development of normal social relationships. The neuropeptide oxytocin (OT) is necessary for social recognition in male and female mice, with its effects being modulated by estrogens in females. In previous studies, mice whose genes for the estrogen receptor-alpha (alpha-ERKO) and estrogen receptor-beta (beta-ERKO) as well as OTKO were knocked out failed to habituate to a repeatedly presented conspecific and to dishabituate when the familiar mouse is replaced by a novel animal (Choleris et al. 2003, Proc Natl Acad Sci USA 100, 6192-6197). However, a binary social discrimination assay, where animals are given a simultaneous choice between a familiar and a previously unknown individual, offers a more direct test of social recognition. Here, we used alpha-ERKO, beta-ERKO, and OTKO female mice in the binary social discrimination paradigm. Differently from their wild-type controls, when given a choice, the KO mice showed either reduced (beta-ERKO) or completely impaired (OTKO and alpha-ERKO) social discrimination. Detailed behavioral analyses indicate that all of the KO mice have reduced anxiety-related stretched approaches to the social stimulus with no overall impairment in horizontal and vertical activity, non-social investigation, and various other behaviors such as, self-grooming, digging, and inactivity. Therefore, the OT, ER-alpha, and ER-beta genes are necessary, to different degrees, for social discrimination and, thus, for the modulation of social behavior (e.g. aggression, affiliation).

  6. A review of estrogen receptor/androgen receptor genomics in male breast cancer.

    PubMed

    Severson, Tesa M; Zwart, Wilbert

    2017-03-01

    Male breast cancer is a rare disease, of which little is known. In contrast to female breast cancer, the very vast majority of all cases are positive for estrogen receptor alpha (ERα), implicating the function of this steroid hormone receptor in tumor development and progression. Consequently, adjuvant treatment of male breast cancer revolves around inhibition of ERα. In addition, the androgen receptor (AR) gradually receives more attention as a relevant novel target in breast cancer treatment. Importantly, the rationale of treatment decision making is strongly based on parallels with female breast cancer. Yet, prognostic indicators are not necessarily the same in breast cancer between both genders, complicating translatability of knowledge developed in female breast cancer toward male patients. Even though ERα and AR are expressed both in female and male disease, are the genomic functions of both steroid hormone receptors conserved between genders? Recent studies have reported on mutational and epigenetic similarities and differences between male and female breast cancer, further suggesting that some features are strongly conserved between the two diseases, whereas others are not. This review critically discusses the recent developments in the study of male breast cancer in relation to ERα and AR action and highlights the potential future studies to further elucidate the genomic regulation of this rare disease. © 2017 Society for Endocrinology.

  7. The evolution of selective estrogen receptor modulators in osteoporosis therapy

    PubMed Central

    2012-01-01

    Selective estrogen receptor modulators (SERMs), which exhibit estrogen receptor agonist or antagonist activity based on the target tissue, have evolved through multiple generations for the prevention and/or treatment of postmenopausal osteoporosis. An ideal SERM would protect bone without stimulating the breast or endometrium. Raloxifene, lasofoxifene, and bazedoxifene have demonstrated unique preclinical profiles. Raloxifene, lasofoxifene, and bazedoxifene have shown significant reduction in the risk of vertebral fracture and improvement in bone mineral density versus placebo in postmenopausal women with osteoporosis. Raloxifene has been shown to reduce the risk of non-vertebral fractures in women with severe prevalent fractures at baseline. Lasofoxifene 0.5 mg, but not lasofoxifene 0.25 mg, has shown reduction in the incidence of non-vertebral fractures. Bazedoxifene 20 mg has been associated with a significant reduction in the risk of non-vertebral fracture versus placebo and raloxifene 60 mg in women at higher baseline fracture risk. Neither raloxifene, lasofoxifene, nor bazedoxifene has shown an increase in the incidence of endometrial hyperplasia or carcinoma. All SERMs have been associated with increased venous thromboembolic events and hot flushes. SERMs are effective alternatives for women who cannot tolerate or are unwilling to take bisphosphonates and may be appropriate for women at higher risk of fracture, particularly younger women who expect to remain on therapy for many years and are concerned about the long-term safety of bisphosphonates. PMID:22853318

  8. Progesterone induces progesterone receptor gene (PGR) expression via rapid activation of protein kinase pathways required for cooperative estrogen receptor alpha (ER) and progesterone receptor (PR) genomic action at ER/PR target genes.

    PubMed

    Diep, Caroline H; Ahrendt, Hannah; Lange, Carol A

    2016-10-01

    Progesterone Receptors (PRs) are critical effectors of estrogen receptor (ER) signaling required for mammary gland development and reproductive proficiency. In breast and reproductive tract malignancies, PR expression is a clinical prognostic marker of ER action. While estrogens primarily regulate PR expression, other factors likely contribute to a dynamic range of receptor expression across diverse tissues. In this study, we identified estrogen-independent but progestin (R5020)-dependent regulation of ER target genes including PGR in ER+/PR+ cancer cell lines. R5020 (10nM-10μM range) induced dose-dependent PR mRNA and protein expression in the absence of estrogen but required both PR and ERα. Antagonists of either PR (RU486, onapristone) or ERα (ICI 182,780) attenuated R5020 induction of TFF1, CTSD, and PGR. Chromatin immunoprecipitation (ChIP) assays performed on ER+/PR+ cells demonstrated that both ERα and PR were recruited to the same ERE/Sp1 site-containing region of the PGR proximal promoter in response to high dose progestin (10μM). Recruitment of ERα and PR to chromatin and subsequent PR mRNA induction were dependent upon rapid activation of MAPK/ERK and AKT; inhibition of these kinase pathways via U0126 or LY294002 blocked these events. Overall, we have identified a novel mechanism of ERα activation initiated by rapid PR-dependent kinase pathway activation and associated with phosphorylation of ERα Ser118 for estrogen-independent but progestin-dependent ER/PR cross talk. These studies may provide insight into mechanisms of persistent ER-target gene expression during periods of hormone (i.e. estrogen) ablation and suggest caution following prolonged treatment with aromatase or CYP17 inhibitors (i.e. contexts when progesterone levels may be abnormally elevated). Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Estrogen receptors and biologic response in rat parathyroid tissue and C cells.

    PubMed Central

    Naveh-Many, T; Almogi, G; Livni, N; Silver, J

    1992-01-01

    The expression of the PTH and calcitonin genes is dramatically decreased by 1,25(OH)2D3 in vivo, and the PTH gene expression is increased by hypocalcemia. We have now studied the effect of estrogens on the expression of these genes in vivo. 17 beta-Estradiol, given to ovariectomized rats, led to a fourfold increase in PTH mRNA and calcitonin mRNA levels. These effects occurred 24 h after single injections of 37-145 nmol estradiol, or after constant infusions of 12 pmol/d for 1 or 2 wk, where there was no effect on serum calcium levels. The estrogen receptor mRNA was demonstrated in the thyroparathyroid tissue by polymerase chain reaction. The estrogen binding was localized to the parathyroid and C cells by immunohistochemistry. Uterus weight was increased by repeated larger doses (73 nmol/d x 7) of estradiol, but not by the small doses (12 pmol/d for 1 or 2 wk) which were effective on the PTH and calcitonin genes, suggesting a sensitive endocrine effect. These results confirm that the parathyroid and C cells are target organs for estrogen, leading to an increased expression of PTH and calcitonin, which by their combined anabolic effect on bone would help prevent osteoporosis. Images PMID:1469095

  10. G protein-coupled estrogen receptor (GPER) mediates NSCLC progression induced by 17β-estradiol (E2) and selective agonist G1.

    PubMed

    Liu, Changyu; Liao, Yongde; Fan, Sheng; Tang, Hexiao; Jiang, Zhixiao; Zhou, Bo; Xiong, Jing; Zhou, Sheng; Zou, Man; Wang, Jianmiao

    2015-04-01

    Estrogen classically drives lung cancer development via estrogen receptor β (ERβ). However, fulvestrant, an anti-estrogen-based endocrine therapeutic treatment, shows limited effects for non-small cell lung cancer (NSCLC) in phase II clinical trials. G protein-coupled estrogen receptor (GPER), a third estrogen receptor that binds to estrogen, has been found to be activated by fulvestrant, stimulating the progression of breast, endometrial, and ovarian cancers. We here demonstrated that cytoplasm-GPER (cGPER) (80.49 %) and nucleus-GPER (53.05 %) were detected by immunohistochemical analysis in NSCLC samples. cGPER expression was related to stages IIIA-IV, lymph node metastasis, and poorly differentiated NSCLC. Selective agonist G1 and 17β-estradiol (E2) promoted the GPER-mediated proliferation, invasion, and migration of NSCLC cells. Additionally, in vitro administration of E2 and G1 increased the number of tumor nodules, tumor grade, and tumor index in a urethane-induced adenocarcinoma model. Importantly, the pro-tumorigenic effects of GPER induced by E2 were significantly reduced by co-administering the GPER inhibitor G15 and the ERβ inhibitor fulvestrant, as compared to administering fulvestrant alone both in vitro and in vivo. Moreover, the phosphorylation of MAPK and Akt was involved in E2/G1-induced GPER activation. In conclusion, our results indicated that a pro-tumor function of GPER exists that mediated E2-/G1-dependent NSCLC progression and showed better efficiency regarding the co-targeting of GPER and ERβ, providing a rationale for further investigation of anti-estrogen clinical therapy.

  11. Isoliquiritigenin exhibits anti-proliferative properties in the pituitary independent of estrogen receptor function

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weis, Karen E.; Raetzman, Lori T., E-mail: raetzma

    The plant flavonoid isoliquiritigenin (ISL) is a botanical estrogen widely taken as an herbal supplement to ease the symptoms of menopause. ISL has been also shown to have anti-tumor properties in a number of cancer cell backgrounds. However, the effects of ISL on normal cells are less well known and virtually unstudied in the context of the pituitary gland. We have established a pituitary explant culture model to screen chemical agents for gene expression changes within the pituitary gland during a period of active proliferation and differentiation. Using this whole-organ culture system we found ISL to be weakly estrogenic basedmore » on its ability to induce Cckar mRNA expression, an estrogen receptor (ER) mediated gene. Using a range of ISL from 200 nM to 200 μM, we discovered that ISL promoted cell proliferation at a low concentration, yet potently inhibited proliferation at the highest concentration. ICI 182,780 failed to antagonize ISL's repression of pituitary cell proliferation, indicating the effect is independent of ER signaling. Coincident with a decrease in proliferating cells, we observed down-regulation of transcript for cyclin D2 and E2 and a strong induction of mRNA and protein for the cyclin dependent kinase inhibitor Cdkn1a (p21). Importantly, high dose ISL did not alter the balance of progenitor vs. differentiated cell types within the pituitary explants and they seemed otherwise healthy; however, TUNEL staining revealed an increase in apoptotic cell death in ISL treated cultures. Our results merit further examination of ISL as an anti-tumor agent in the pituitary gland. - Highlights: • Isoliquiritigenin possesses weak estrogenic activity based on induction of Cckar. • ISL can be anti-proliferative in pituitary explants without altering cell lineages. • Anti-proliferative behavior of ISL is not estrogen receptor mediated. • ISL induces p21 expression leading to cell cycle arrest and apoptosis.« less

  12. CLONING, EXPRESSION AND CHARACTERIZATION OF THE ANDROGEN RECEPTOR AND ISOLATION OF ESTROGEN RECEPTOR ALPHA FROM THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    In vitro screening assays designed to identify hormone mimics or antagonists, including those recommended for use in the EPA's Tier 1 screening battery, typically use mammalian estrogen (ER) and androgen receptors (AR) such as rat or human. Although we know that the amino acid s...

  13. Estrogens and Coronary Artery Disease: New Clinical Perspectives.

    PubMed

    Meyer, M R; Barton, M

    2016-01-01

    In premenopausal women, endogenous estrogens are associated with reduced prevalence of arterial hypertension, coronary artery disease, myocardial infarction, and stroke. Clinical trials conducted in the 1990s such as HERS, WHI, and WISDOM have shown that postmenopausal treatment with horse hormone mixtures (so-called conjugated equine estrogens) and synthetic progestins adversely affects female cardiovascular health. Our understanding of rapid (nongenomic) and chronic (genomic) estrogen signaling has since advanced considerably, including identification of a new G protein-coupled estrogen receptor (GPER), which like the "classical" receptors ERα and ERβ is highly abundant in the cardiovascular system. Here, we discuss the role of estrogen receptors in the pathogenesis of coronary artery disease and review natural and synthetic ligands of estrogen receptors as well as their effects in physiology, on cardiovascular risk factors, and atherosclerotic vascular disease. Data from preclinical and clinical studies using nonselective compounds activating GPER, which include selective estrogen receptor modulators such as tamoxifen or raloxifene, selective estrogen receptor downregulators such as Faslodex™ (fulvestrant/ICI 182,780), vitamin B3 (niacin), green tea catechins, and soy flavonoids such as genistein or resveratrol, strongly suggest that activation of GPER may afford therapeutic benefit for primary and secondary prevention in patients with or at risk for coronary artery disease. Evidence from preclinical studies suggest similar efficacy profiles for selective small molecule GPER agonists such as G-1 which are devoid of uterotrophic activity. Further clinical research in this area is warranted to provide opportunities for future cardiovascular drug development. © 2016 Elsevier Inc. All rights reserved.

  14. [The estrogenic effect of formononetin and its effect on the expression of rats' atrium estrogen receptors].

    PubMed

    Xing, Dian-Xia; Liu, Xian-Ling; Xue, Cun-Kuan; Huang, Qi; Liu, Zhi-Gao; Xiong, Liang

    2010-09-01

    To observe the estrogenic effect of formononetin and its effect on the expressions of atrial estrogen receptor subtypes alpha and beta (ERalpha and ERbeta). 50 femal rats were randomly divided into five groups: sham group, model group, nilestriol group, formononetin groups of low and high dose. Rats in sham group were cut a piece of fat before closing the abdomen, the others were ovariectomized. Vaginal exfoliated cell were observed from the fifth day to the tenth after operation to test if the model is successful. The sham and model group were given nomal saline in 10 mL/kg by gavage, the remaining three groups were given nilestriol 2.5 mg/(kg x w), low [20 mg/(kg x d) land high dose [100 mg/(kg x d)) of formononetin by gavage respectively. In the 8th week, vaginal exfoliated cell were observed, then decapitated the rats, removed the uterus, weighed and take wright staining microscopy. The relative expressions of ERalpha and ERbeta of right atrium were detected by RT-PCR. The vaginal cells exhibit a change of estrus after had been fed with high dose of formononetin after 8 weeks. Formononetin increase the uterus coefficient and the expression of atrial ERbeta (P < 0.01), but it dose not have any effect on the expression of ERalpha (P > 0.05). Formononetin have estrogenic effect in ovariectomized rats, and it can markedly upregulate the expression of rats' atrial ERbeta.

  15. Genetic variants of estrogen beta and leptin receptors may cause gynecomastia in adolescent.

    PubMed

    Eren, Erdal; Edgunlu, Tuba; Korkmaz, Huseyin Anil; Cakir, Esra Deniz Papatya; Demir, Korcan; Cetin, Esin Sakalli; Celik, Sevim Karakas

    2014-05-15

    Gynecomastia is a benign breast enlargement in males that affects approximately one-third of adolescents. The exact mechanism is not fully understood; however, it has been proposed that estrogen receptors and aromatase enzyme activity may play important roles in the pathogenesis of gynecomastia. While many studies have reported that aromatase enzyme (CYP19) gene polymorphism is associated with gynecomastia, only one study has shown a relationship between estrogen receptor (ER) alpha and beta gene polymorphism and gynecomastia. Thus, the aim of this study was to evaluate the relationships between CYP19 (rs2414096), ER alpha (rs2234693), ER beta (rs4986938), leptin (rs7799039), and leptin receptor (rs1137101) gene polymorphisms and gynecomastia. This study included 107 male adolescents with gynecomastia and 97 controls. Total serum testosterone (T) and estradiol (E2) levels were measured, and DNA was extracted from whole blood using the PCR-RFLP technique. The polymorphic distributions of CYP19, ER alpha, ER beta, leptin and leptin receptor genes were compared. The median E2 level was 12.41 (5.00-65.40) pg/ml in the control group and 16.86 (2.58-78.47) pg/ml in the study group (p<0.001). The median T level was 2.19 (0.04-7.04) ng/ml in the control group and 1.46 (0.13-12.02) ng/ml in the study group (p=0.714). There was a significant relationship between gynecomastia and leptin receptor rs1137101 (p=0.002) and ER beta receptor rs4986938 gene polymorphisms (p=0.002). According to our results, increased E2 level and ER beta gene rs4986938 polymorphism might explain why some adolescents have gynecomastia. Leptin receptor gene rs1137101 polymorphism might affect susceptibility to gynecomastia. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Identification of Breast Cancer Inhibitors Specific for G Protein-Coupled Estrogen Receptor (GPER)-Expressing Cells.

    PubMed

    Aiello, Francesca; Carullo, Gabriele; Giordano, Francesca; Spina, Elena; Nigro, Alessandra; Garofalo, Antonio; Tassini, Sabrina; Costantino, Gabriele; Vincetti, Paolo; Bruno, Agostino; Radi, Marco

    2017-08-22

    Together with estrogen receptors ERα and ERβ, the G protein-coupled estrogen receptor (GPER) mediates important pathophysiological signaling pathways induced by estrogens and is currently regarded as a promising target for ER-negative (ER-) and triple-negative (TN) breast cancer. Only a few selective GPER modulators have been reported to date, and their use in cancer cell lines has often led to contradictory results. Herein we report the application of virtual screening and cell-based studies for the identification of new chemical scaffolds with a specific antiproliferative effect against GPER-expressing breast cancer cell lines. Out of the four different scaffolds identified, 8-chloro-4-(4-chlorophenyl)pyrrolo[1,2-a]quinoxaline 14 c was found to be the most promising compound able to induce: 1) antiproliferative activity in GPER-expressing cell lines (MCF7 and SKBR3), similarly to G15; 2) no effect on cells that do not express GPER (HEK293); 3) a decrease in cyclin D1 expression; and 4) a sustained induction of cell-cycle negative regulators p53 and p21. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. G-protein-coupled estrogen receptor 1 is anatomically positioned to modulate synaptic plasticity in the mouse hippocampus.

    PubMed

    Waters, Elizabeth M; Thompson, Louisa I; Patel, Parth; Gonzales, Andreina D; Ye, Hector Zhiyu; Filardo, Edward J; Clegg, Deborah J; Gorecka, Jolanta; Akama, Keith T; McEwen, Bruce S; Milner, Teresa A

    2015-02-11

    Both estrous cycle and sex affect the numbers and types of neuronal and glial profiles containing the classical estrogen receptors α and β, and synaptic levels in the rodent dorsal hippocampus. Here, we examined whether the membrane estrogen receptor, G-protein-coupled estrogen receptor 1 (GPER1), is anatomically positioned in the dorsal hippocampus of mice to regulate synaptic plasticity. By light microscopy, GPER1-immunoreactivity (IR) was most noticeable in the pyramidal cell layer and interspersed interneurons, especially those in the hilus of the dentate gyrus. Diffuse GPER1-IR was found in all lamina but was most dense in stratum lucidum of CA3. Ultrastructural analysis revealed discrete extranuclear GPER1-IR affiliated with the plasma membrane and endoplasmic reticulum of neuronal perikarya and dendritic shafts, synaptic specializations in dendritic spines, and clusters of vesicles in axon terminals. Moreover, GPER1-IR was found in unmyelinated axons and glial profiles. Overall, the types and amounts of GPER1-labeled profiles were similar between males and females; however, in females elevated estrogen levels generally increased axonal labeling. Some estradiol-induced changes observed in previous studies were replicated by the GPER agonist G1: G1 increased PSD95-IR in strata oriens, lucidum, and radiatum of CA3 in ovariectomized mice 6 h after administration. In contrast, estradiol but not G1 increased Akt phosphorylation levels. Instead, GPER1 actions in the synapse may be due to interactions with synaptic scaffolding proteins, such as SAP97. These results suggest that although estrogen's actions via GPER1 may converge on the same synaptic elements, different pathways are used to achieve these actions. Copyright © 2015 the authors 0270-6474/15/352384-14$15.00/0.

  18. COMPARATIVE DOCKING STUDIES OF THE BINDING OF POLYCYCLIC AROMATIC HYDROCARBONS TO THE ESTROGEN RECEPTOR

    EPA Science Inventory

    The interactions of several PAHs, and some of their possible metabolites, with the ligand binding domain of the estrogen receptor have been examined using molecular docking and quantum mechanical methods. The geometries of the PAHs were optimized at the Hartree-Fock level and the...

  19. Competitive Binding Assay for the G-Protein-Coupled Receptor 30 (GPR30) or G-Protein-Coupled Estrogen Receptor (GPER).

    PubMed

    Thekkumkara, Thomas; Snyder, Russell; Karamyan, Vardan T

    2016-01-01

    The role of 2-methoxyestradiol is becoming a major area of investigation because of its therapeutic utility, though its mechanism is not fully explored. Recent studies have identified the G-protein-coupled receptor 30 (GPR30, GPER) as a high-affinity membrane receptor for 2-methoxyestradiol. However, studies aimed at establishing the binding affinities of steroid compounds for specific targets are difficult, as the tracers are highly lipophilic and often result in nonspecific binding in lipid-rich membrane preparations with low-level target receptor expression. 2-Methoxyestradiol binding studies are essential to elucidate the underlying effects of this novel estrogen metabolite and to validate its targets; therefore, this competitive receptor-binding assay protocol was developed in order to assess the membrane receptor binding and affinity of 2-methyoxyestradiol.

  20. Tetrahydroisoquinoline alkaloids mimic direct but not receptor-mediated inhibitory effects of estrogens and phytoestrogens on testicular endocrine function. Possible significance for Leydig cell insufficiency in alcohol addiction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stammel, W.; Thomas, H.; Staib, W.

    1991-01-01

    Possible effects of various tetrahydroisoquinolines (TIQs) on rat testicular endocrine function were tested in vitro in order to prove whether these compounds may be mediators of the development of Leydig cell insufficiency. TIQ effects on different levels of regulation of testis function were compared in vitro with estrogen effects, since both classes of compounds have structural similarities. Gonadotropin-stimulated testosterone production by testicular Leydig cells was inhibited by tetrahydropapaveroline and isosalsoline, the IC{sub 50} values being comparable to those of estradiol, 2-hydroxyestradiol, and the phytoestrogens, coumestrol and genistein; salsolinol and salsoline were less effective, and salsolidine was ineffective. None of thesemore » TIQs interacted significantly with testicular estrogen receptor as analyzed by estradiol displacement. However, tetrahydropapaveroline, isosalsoline and salsolinol competitively inhibited substrate binding to cytochrome P45OXVII, with similar efficiency as the estrogens did; salsoline and salsolidine were again much less effective.« less

  1. Interactions between estrogen receptors and metabotropic glutamate receptors and their impact on drug addiction in females.

    PubMed

    Tonn Eisinger, Katherine R; Gross, Kellie S; Head, Brian P; Mermelstein, Paul G

    2018-03-10

    Estrogen receptors α and β (ERα and ERβ) have a unique relationship with metabotropic glutamate receptors (mGluRs) in the female rodent brain such that estradiol is able to recruit intracellular G-protein signaling cascades to influence neuronal physiology, structure, and ultimately behavior. While this association between ERs and mGluRs exists in many cell types and brain regions, its effects are perhaps most striking in the nucleus accumbens (NAc). This review will discuss the original characterization of ER/mGluR signaling and how estradiol activity in the NAc confers increased sensitivity to drugs of abuse in females through this mechanism. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. Identifying Metabolically Active Chemicals Using a Consensus Quantitative Structure Activity Model for Estrogen Receptor Binding

    EPA Science Inventory

    Endocrine disrupting chemicals (EDCs) are abundant throughout the environment and can alter neurodevelopment, behavior, and reproductive success of humans and other species by perturbing signaling pathways related to the estrogen receptor (ER). A recent study compared results acr...

  3. Tamoxifen and ICI 182, 780 activate hypothalamic G protein-coupled estrogen receptor 1 to rapidly facilitate lordosis in female rats

    PubMed Central

    Long, Nathan; Long, Bertha; Mana, Asma; Le, Dream; Nguyen, Lam; Chokr, Sima; Sinchak, Kevin

    2017-01-01

    In the female rat, sexual receptivity (lordosis) can be facilitated by sequential activation of estrogen receptor (ER) α and G protein-coupled estrogen receptor 1 (GPER) by estradiol. In the estradiol benzoate (EB) primed ovariectomized (OVX) rat, EB initially binds to ERα in the plasma membrane that complexes with and transactivates metabotropic glutamate receptor 1a to activate β-endorphin neurons in the arcuate nucleus of the hypothalamus (ARH) that project to the medial preoptic nucleus (MPN). This activates MPN μ-opioid receptors (MOP), inhibiting lordosis. Infusion of non-esterified 17β-estradiol into the ARH rapidly reduces MPN MOP activation and facilitates lordosis via GPER. Tamoxifen (TAM) and ICI 182,780 (ICI) are selective estrogen receptor modulators that activate GPER. Therefore, we tested the hypothesis that TAM and ICI rapidly facilitate lordosis via activation of GPER in the ARH. Our first experiment demonstrated that injection of TAM intraperitoneal, or ICI into the lateral ventricle, deactivated MPN MOP and facilitated lordosis in EB-primed rats. We then tested whether TAM and ICI were acting rapidly through a GPER dependent pathway in the ARH. In EB-primed rats, ARH infusion of either TAM or ICI facilitated lordosis and reduced MPN MOP activation within 30 minutes compared to controls. These effects were blocked by pretreatment with the GPER antagonist, G15. Our findings demonstrate that TAM and ICI deactivate MPN MOP and facilitate lordosis in a GPER dependent manner. Thus, TAM and ICI may activate GPER in the CNS to produce estrogenic actions in neural circuits that modulate physiology and behavior. PMID:28063803

  4. Tamoxifen and ICI 182,780 activate hypothalamic G protein-coupled estrogen receptor 1 to rapidly facilitate lordosis in female rats.

    PubMed

    Long, Nathan; Long, Bertha; Mana, Asma; Le, Dream; Nguyen, Lam; Chokr, Sima; Sinchak, Kevin

    2017-03-01

    In the female rat, sexual receptivity (lordosis) can be facilitated by sequential activation of estrogen receptor (ER) α and G protein-coupled estrogen receptor 1 (GPER) by estradiol. In the estradiol benzoate (EB) primed ovariectomized (OVX) rat, EB initially binds to ERα in the plasma membrane that complexes with and transactivates metabotropic glutamate receptor 1a to activate β-endorphin neurons in the arcuate nucleus of the hypothalamus (ARH) that project to the medial preoptic nucleus (MPN). This activates MPN μ-opioid receptors (MOP), inhibiting lordosis. Infusion of non-esterified 17β-estradiol into the ARH rapidly reduces MPN MOP activation and facilitates lordosis via GPER. Tamoxifen (TAM) and ICI 182,780 (ICI) are selective estrogen receptor modulators that activate GPER. Therefore, we tested the hypothesis that TAM and ICI rapidly facilitate lordosis via activation of GPER in the ARH. Our first experiment demonstrated that injection of TAM intraperitoneal, or ICI into the lateral ventricle, deactivated MPN MOP and facilitated lordosis in EB-primed rats. We then tested whether TAM and ICI were acting rapidly through a GPER dependent pathway in the ARH. In EB-primed rats, ARH infusion of either TAM or ICI facilitated lordosis and reduced MPN MOP activation within 30min compared to controls. These effects were blocked by pretreatment with the GPER antagonist, G15. Our findings demonstrate that TAM and ICI deactivate MPN MOP and facilitate lordosis in a GPER dependent manner. Thus, TAM and ICI may activate GPER in the CNS to produce estrogenic actions in neural circuits that modulate physiology and behavior. Published by Elsevier Inc.

  5. Aromatase expression increases the survival and malignancy of estrogen receptor positive breast cancer cells.

    PubMed

    Mukhopadhyay, Keya De; Liu, Zhao; Bandyopadhyay, Abhik; Kirma, Nameer B; Tekmal, Rajeshwar R; Wang, Shui; Sun, Lu-Zhe

    2015-01-01

    In postmenopausal women, local estrogen produced by adipose stromal cells in the breast is believed to support estrogen receptor alpha (ERα) positive breast cancer cell survival and growth. This raises the question of how the ERα positive metastatic breast cancer cells survive after they enter blood and lymph circulation, where estrogen level is very low in postmenopausal women. In this study, we show that the aromatase expression increased when ERα positive breast cancer cells were cultured in suspension. Furthermore, treatment with the aromatase substrate, testosterone, inhibited suspension culture-induced apoptosis whereas an aromatase inhibitor attenuated the effect of testosterone suggesting that suspended circulating ERα positive breast cancer cells may up-regulate intracrine estrogen activity for survival. Consistent with this notion, a moderate level of ectopic aromatase expression rendered a non-tumorigenic ERα positive breast cancer cell line not only tumorigenic but also metastatic in female nude mice without exogenous estrogen supplementation. The increased malignant phenotype was confirmed to be due to aromatase expression as the growth of orthotopic tumors regressed with systemic administration of an aromatase inhibitor. Thus, our study provides experimental evidence that aromatase plays an important role in the survival of metastatic ERα breast cancer cells by suppressing anoikis.

  6. Immunolocalization of Leptin Receptor and mRNA Expression of Leptin and Estrogen Receptors as well as Caspases in the Chorioallantoic Membrane (CAM) of the Chicken Embryo.

    PubMed

    Grzegorzewska, Agnieszka K; Lis, Marcin W; Sechman, Andrzej

    The chicken chorioallantoic membrane (CAM) is used as a model in tests of angiogenesis, the biocompatibility of materials as well as tumor invasive potential. To assess the properties of CAM tissue, the localization of leptin receptor in the CAM, and the mRNA expression of two leptin receptor isoforms, estrogen receptors (ERα and ERβ) and caspases (-1 and -3) in the CAM on embryonic days 12 (E12), 15 (E15) and 18 (E18) were investigated. The leptin receptor was immunolocalized in each structure of the CAM (chorionic epithelium, allantoic epithelium, mesodermal layer and the walls of blood vessels) and did not change among analyzed stages of embryonic development (E12, E15 and E18) and between sexes. Expression of mRNA of genes encoding leptin and estrogen receptors as well as caspases was detected in the CAM of female and male chicken embryos at all three analysed stages of development. The relative mRNA expression of the long form of leptin receptor exceeded that of its short isoform. The mRNA expression of ERβ was significantly higher than ERα as well as caspase-3 in comparison with caspase-1. There were no differences in mRNA expression of these genes between sexes and among analyzed developmental days. The results indicate that the CAM is a target tissue for leptin as well as for estrogens and that CAM development is partially regulated by caspase-1 and caspase-3 dependent cell death. These results should be taken into consideration in studies in which the CAM is used as an experimental model.

  7. Interplay between estrogen receptor and AKT in Estradiol-induced alternative splicing

    PubMed Central

    2013-01-01

    Background Alternative splicing is critical for generating complex proteomes in response to extracellular signals. Nuclear receptors including estrogen receptor alpha (ERα) and their ligands promote alternative splicing. The endogenous targets of ERα:estradiol (E2)-mediated alternative splicing and the influence of extracellular kinases that phosphorylate ERα on E2-induced splicing are unknown. Methods MCF-7 and its anti-estrogen derivatives were used for the majority of the assays. CD44 mini gene was used to measure the effect of E2 and AKT on alternative splicing. ExonHit array analysis was performed to identify E2 and AKT-regulated endogenous alternatively spliced apoptosis-related genes. Quantitative reverse transcription polymerase chain reaction was performed to verify alternative splicing. ERα binding to alternatively spliced genes was verified by chromatin immunoprecipitation assay. Bromodeoxyuridine incorporation-ELISA and Annexin V labeling assays were done to measure cell proliferation and apoptosis, respectively. Results We identified the targets of E2-induced alternative splicing and deconstructed some of the mechanisms surrounding E2-induced splicing by combining splice array with ERα cistrome and gene expression array. E2-induced alternatively spliced genes fall into at least two subgroups: coupled to E2-regulated transcription and ERα binding to the gene without an effect on rate of transcription. Further, AKT, which phosphorylates both ERα and splicing factors, influenced ERα:E2 dependent splicing in a gene-specific manner. Genes that are alternatively spliced include FAS/CD95, FGFR2, and AXIN-1. E2 increased the expression of FGFR2 C1 isoform but reduced C3 isoform at mRNA level. E2-induced alternative splicing of FAS and FGFR2 in MCF-7 cells correlated with resistance to FAS activation-induced apoptosis and response to keratinocyte growth factor (KGF), respectively. Resistance of MCF-7 breast cancer cells to the anti-estrogen tamoxifen

  8. Molecular modeling and molecular dynamics simulation studies on the interactions of hydroxylated polychlorinated biphenyls with estrogen receptor-β.

    PubMed

    Li, Xiaolin; Ye, Li; Wang, Xiaoxiang; Shi, Wei; Qian, XiangPing; Zhu, YongLiang; Yu, HongXia

    2013-10-01

    Endocrine-disrupting chemicals have attracted great concern. As major metabolites of polychlorinated biphenyls (PCBs), hydroxylated polychlorinated biphenyls (HO-PCBs) may disrupt estrogen hormone status because of their structural similarity to estrogen endogenous compounds. However, interactions between HO-PCBs and estrogen receptors (ERs) are not fully understood. In the present work, a molecular modeling study combining molecular docking, molecular dynamics simulations, and binding free energy calculations was performed to characterize the interactions of three HO-PCBs (4'-HO-PCB50, 2'-HO-PCB65, and 4'-HO-PCB69) having much different estrogenic activities with ERβ. Docking results showed that binding between ligands and ERβ was stabilized by hydrogen bond and hydrophobic interactions. The binding free energies of three ligands with ERβ were calculated, and further binding free energy decomposition analysis indicated that the dominating driving force of the binding between the ligands and ERβ was the van der Waals interaction. Some key residues, such as Leu298, Phe356, Gly472, His475, and Leu476, played important roles in ligand-receptor interactions by forming hydrophobic and hydrogen bond interactions with ligands. The results may be beneficial to increase understanding of the interactions between HO-PCBs and ERβ.

  9. Genome-wide activity of unliganded estrogen receptor-α in breast cancer cells

    PubMed Central

    Caizzi, Livia; Ferrero, Giulio; Cutrupi, Santina; Cordero, Francesca; Ballaré, Cecilia; Miano, Valentina; Reineri, Stefania; Ricci, Laura; Friard, Olivier; Testori, Alessandro; Corà, Davide; Caselle, Michele; Di Croce, Luciano; De Bortoli, Michele

    2014-01-01

    Estrogen receptor-α (ERα) has central role in hormone-dependent breast cancer and its ligand-induced functions have been extensively characterized. However, evidence exists that ERα has functions that are independent of ligands. In the present work, we investigated the binding of ERα to chromatin in the absence of ligands and its functions on gene regulation. We demonstrated that in MCF7 breast cancer cells unliganded ERα binds to more than 4,000 chromatin sites. Unexpectedly, although almost entirely comprised in the larger group of estrogen-induced binding sites, we found that unliganded-ERα binding is specifically linked to genes with developmental functions, compared with estrogen-induced binding. Moreover, we found that siRNA-mediated down-regulation of ERα in absence of estrogen is accompanied by changes in the expression levels of hundreds of coding and noncoding RNAs. Down-regulated mRNAs showed enrichment in genes related to epithelial cell growth and development. Stable ERα down-regulation using shRNA, which caused cell growth arrest, was accompanied by increased H3K27me3 at ERα binding sites. Finally, we found that FOXA1 and AP2γ binding to several sites is decreased upon ERα silencing, suggesting that unliganded ERα participates, together with other factors, in the maintenance of the luminal-specific cistrome in breast cancer cells. PMID:24639548

  10. The unliganded long isoform of estrogen receptor beta stimulates brain ryanodine receptor single channel activity alongside with cytosolic Ca2+

    PubMed Central

    Rybalchenko, Volodymyr; Grillo, Michael A.; Gastinger, Matthew J.; Rybalchenko, Nataliya; Payne, Andrew J.; Koulen, Peter

    2010-01-01

    Ca2+ release from intracellular stores mediated by endoplasmic reticulum membrane ryanodine receptors (RyR) plays a key role in activating and synchronizing downstream Ca2+-dependent mechanisms, in different cells varying from apoptosis to nuclear transcription and development of defensive responses. Recently discovered, atypical “non-genomic” effects mediated by estrogen receptors (ER) include rapid Ca2+ release upon estrogen exposure in conditions implicitly suggesting involvement of RyRs. In the present study, we report various levels of co-localization between RyR type 2 (RyR2) and ER type β (ERβ) in the neuronal cell line HT-22, indicating a possible functional interaction. Electrophysiological analyses revealed a significant increase in single channel ionic currents generated by mouse brain RyRs after application of the soluble monomer of the long form ERβ (ERβ1). The effect was due to a strong increase in open probability of RyR higher open channel sublevels at cytosolic [Ca2+] concentrations of 100 nM, suggesting a synergistic action of ERβ1 and Ca2+ in RyR activation, and a potential contribution to Ca2+-induced Ca2+ release rather than to basal intracellular Ca2+ concentration level at rest. This RyR/ERβ interaction has potential effects on cellular physiology, including roles of shorter ERβ isoforms and modulation of the RyR/ERβ complexes by exogenous estrogens. PMID:19899956

  11. BA321, a novel carborane analog that binds to androgen and estrogen receptors, acts as a new selective androgen receptor modulator of bone in male mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Watanabe, Kenta; Cooperative Major in Advanced Health Science, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei, Tokyo 184-8588; Hirata, Michiko

    Carboranes are a class of carbon-containing polyhedral boron cluster compounds with globular geometry and hydrophobic surface that interact with hormone receptors such as estrogen receptor (ER) and androgen receptor (AR). We have synthesized BA321, a novel carborane compound, which binds to AR. We found here that it also binds to ERs, ERα and ERβ. In orchidectomized (ORX) mice, femoral bone mass was markedly reduced due to androgen deficiency and BA321 restored bone loss in the male, whilst the decreased weight of seminal vesicle in ORX mice was not recovered by administration of BA321. In female mice, BA321 acts as amore » pure estrogen agonist, and restored both the loss of bone mass and uterine atrophy due to estrogen deficiency in ovariectomized (OVX) mice. In bone tissues, the trabecular bone loss occurred in both ORX and OVX mice, and BA321 completely restored the trabecular bone loss in both sexes. Cortical bone loss occurred in ORX mice but not in OVX mice, and BA321 clearly restored cortical bone loss due to androgen deficiency in ORX mice. Therefore, BA321 is a novel selective androgen receptor modulator (SARM) that may offer a new therapy option for osteoporosis in the male. - Highlights: • A novel carborane compound BA321 binds to both AR and ERs, ERα and ERβ. • BA321 restores bone loss in orchidectomized mice without effects on sex organ. • BA321 acts as an estrogen agonist in bone and uterus in ovariectomized mice. • BA321 may be a new SARM to prevent the loss of musculoskeletal mass in elder men.« less

  12. Perilipin, a critical regulator of fat storage and breakdown, is a target gene of estrogen receptor-related receptor {alpha}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akter, Mst. Hasina; Yamaguchi, Tomohiro; Hirose, Fumiko

    2008-04-11

    Perilipin is a protein localized on lipid droplet surfaces in adipocytes and steroidogenic cells, playing a central role in regulated lipolysis. Expression of the perilipin gene is markedly induced during adipogenesis. We found that transcription from the perilipin gene promoter is activated by an orphan nuclear receptor, estrogen receptor-related receptor (ERR){alpha}. A response element to this receptor was identified in the promoter region by a gene reporter assay, the electrophoretic-gel mobility-shift assay and the chromatin immunoprecipitation assay. Peroxisome proliferator-activated receptor {gamma} coactivator (PGC)-1{alpha} enhanced, whereas small heterodimer partner (SHP) repressed, the transactivating function of ERR{alpha} on the promoter. Thus, themore » perilipin gene expression is regulated by a transcriptional network controlling energy metabolism, substantiating the functional importance of perilipin in the maintenance of body energy balance.« less

  13. Regulation of Estrogen Receptor α Expression in the Hypothalamus by Sex Steroids: Implication in the Regulation of Energy Homeostasis.

    PubMed

    Liu, Xian; Shi, Haifei

    2015-01-01

    Sex differences exist in the complex regulation of energy homeostasis that utilizes central and peripheral systems. It is widely accepted that sex steroids, especially estrogens, are important physiological and pathological components in this sex-specific regulation. Estrogens exert their biological functions via estrogen receptors (ERs). ERα, a classic nuclear receptor, contributes to metabolic regulation and sexual behavior more than other ER subtypes. Physiological and molecular studies have identified multiple ERα-rich nuclei in the hypothalamus of the central nervous system (CNS) as sites of actions that mediate effects of estrogens. Much of our understanding of ERα regulation has been obtained using transgenic models such as ERα global or nuclei-specific knockout mice. A fundamental question concerning how ERα is regulated in wild-type animals, including humans, in response to alterations in steroid hormone levels, due to experimental manipulation (i.e., castration and hormone replacement) or physiological stages (i.e., puberty, pregnancy, and menopause), lacks consistent answers. This review discusses how different sex hormones affect ERα expression in the hypothalamus. This information will contribute to the knowledge of estrogen action in the CNS, further our understanding of discrepancies in correlation of altered sex hormone levels with metabolic disturbances when comparing both sexes, and improve health issues in postmenopausal women.

  14. Development of an image analysis screen for estrogen receptor alpha (ERα) ligands through measurement of nuclear translocation dynamics.

    PubMed

    Dull, Angie; Goncharova, Ekaterina; Hager, Gordon; McMahon, James B

    2010-11-01

    We have developed a robust high-content assay to screen for novel estrogen receptor alpha (ERα) agonists and antagonists by quantitation of cytoplasmic to nuclear translocation of an estrogen receptor chimera in 384-well plates. The screen utilizes a green fluorescent protein tagged-glucocorticoid/estrogen receptor (GFP-GRER) chimera which consisted of the N-terminus of the glucocorticoid receptor fused to the human ER ligand binding domain. The GFP-GRER exhibited cytoplasmic localization in the absence of ERα ligands, and translocated to the nucleus in response to stimulation with ERα agonists or antagonists. The BD Pathway 435 imaging system was used for image acquisition, analysis of translocation dynamics, and cytotoxicity measurements. The assay was validated with known ERα agonists and antagonists, and the Library of Pharmacologically Active Compounds (LOPAC 1280). Additionally, screening of crude natural product extracts demonstrated the robustness of the assay, and the ability to quantitate the effects of toxicity on nuclear translocation dynamics. The GFP-GRER nuclear translocation assay was very robust, with z' values >0.7, CVs <5%, and has been validated with known ER ligands, and inclusion of cytotoxicity filters will facilitate screening of natural product extracts. This assay has been developed for future primary screening of synthetic, pure natural products, and natural product extracts libraries available at the National Cancer Institute at Frederick. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Estrogen Modulation of MgATPase Activity of Nonmuscle Myosin-II-B Filaments

    PubMed Central

    Gorodeski, George I.

    2008-01-01

    The study tested the hypothesis that estrogen controls epithelial paracellular resistance through modulation of myosin. The objective was to understand how estrogen modulates non-muscle myosin-II-B (NMM-II-B), the main component of the cortical actomyosin in human epithelial cervical cells. Experiments used human cervical epithelial cells CaSki as a model, and end points were NMM-II-B phosphorylation, filamentation, and MgATPase activity. The results were as follows: 1) treatment with estrogen increased phosphorylation and MgATPase activity and decreased NMM-II-B filamentation; 2) estrogen effects could be blocked by antisense nucleotides for the estrogen receptor-α and by ICI-182,780, tamoxifen, and the casein kinase-II (CK2) inhibitor, 5,6-dichloro-1-β-(D)-ribofuranosylbenzimidazole and attenuated by AG1478 and PD98059 (inhibitors of epithelial growth factor receptor and ERK/MAPK) but not staurosporine [blocker of protein kinase C (PKC)]; 3) treatments with the PKC activator sn-1,2-di-octanoyl diglyceride induced biphasic effect on NMM-II-B MgATPase activity: an increase at 1 nM to 1 μM and a decrease in activity at more than 1 μM; 4) sn-1,2-dioctanoyl diglyceride also decreased NMM-II-B filamentation in a monophasic and saturable dose dependence (EC50 1–10 μM); 5) when coincubated directly with purified NMM-II-B filaments, both CK2 and PKC decreased filamentation and increased MgATPase activity; 6) assays done on disassembled NMM-II-B filaments showed MgATPase activity in filaments obtained from estrogen-treated cells but not estrogen-depleted cells; and 7) incubations in vitro with CK2, but not PKC, facilitated MgATPase activity, even in disassembled NMM-II-B filaments. The results suggest that estrogen, in an effect mediated by estrogen receptor-α and CK2 and involving the epithelial growth factor receptor and ERK/MAPK cascades, increases NMM-II-B MgATPase activity independent of NMM-II-B filamentation status. PMID:17023528

  16. Association between polymorphisms of estrogen receptor 2 and benign prostatic hyperplasia

    PubMed Central

    KIM, SU KANG; CHUNG, JOO-HO; PARK, HYUN CHUL; KIM, JUN HO; ANN, JAE HONG; PARK, HUN KUK; LEE, SANG HYUP; YOO, KOO HAN; LEE, BYUNG-CHEOL; KIM, YOUNG OCK

    2015-01-01

    Estrogens and estrogen receptors (ESRs) have been implicated in the stimulation of aberrant prostate growth and the development of prostate diseases. The aim of the present study was to investigate four single nucleotide polymorphisms (SNPs) of the ESR2 gene in order to examine whether ESR2 is a susceptibility gene for benign prostatic hyperplasia (BPH). In order to evaluate whether an association exists between ESR2 and BPH risk, four polymorphisms [rs4986938 (intron), rs17766755 (intron), rs12435857 (intron) and rs1256049 (Val328Val)] of the ESR2 gene were genotyped by direct sequencing. A total of 94 patients with BPH and 79 control subjects were examined. SNPStats and Haploview version 4.2 we used for the genetic analysis. Multiple logistic regression models (codominant1, codominant2, dominant, recessive and log-additive) were produced in order to obtain the odds ratio, 95% confidence interval and P-value. Three SNPs (rs4986938, rs17766755 and rs12435857) showed significant associations with BPH (rs4986938, P=0.015 in log-additive model; rs17766755, P=0.033 in codominant1 model, P=0.019 in dominant model and P=0.020 in log-additive model; rs12435857, P=0.023 in dominant model and P=0.011 in log-additive model). The minor alleles of these SNPs increased the risk of BPH, and the AAC haplotype showed significant association with BPH (χ2=6.34, P=0.0118). These data suggest that the ESR2 gene may be associated with susceptibility to BPH. PMID:26640585

  17. Association between polymorphisms of estrogen receptor 2 and benign prostatic hyperplasia.

    PubMed

    Kim, Su Kang; Chung, Joo-Ho; Park, Hyun Chul; Kim, Jun Ho; Ann, Jae Hong; Park, Hun Kuk; Lee, Sang Hyup; Yoo, Koo Han; Lee, Byung-Cheol; Kim, Young Ock

    2015-11-01

    Estrogens and estrogen receptors (ESRs) have been implicated in the stimulation of aberrant prostate growth and the development of prostate diseases. The aim of the present study was to investigate four single nucleotide polymorphisms (SNPs) of the ESR2 gene in order to examine whether ESR2 is a susceptibility gene for benign prostatic hyperplasia (BPH). In order to evaluate whether an association exists between ESR2 and BPH risk, four polymorphisms [rs4986938 (intron), rs17766755 (intron), rs12435857 (intron) and rs1256049 (Val328Val)] of the ESR2 gene were genotyped by direct sequencing. A total of 94 patients with BPH and 79 control subjects were examined. SNPStats and Haploview version 4.2 we used for the genetic analysis. Multiple logistic regression models (codominant1, codominant2, dominant, recessive and log-additive) were produced in order to obtain the odds ratio, 95% confidence interval and P-value. Three SNPs (rs4986938, rs17766755 and rs12435857) showed significant associations with BPH (rs4986938, P=0.015 in log-additive model; rs17766755, P=0.033 in codominant1 model, P=0.019 in dominant model and P=0.020 in log-additive model; rs12435857, P=0.023 in dominant model and P=0.011 in log-additive model). The minor alleles of these SNPs increased the risk of BPH, and the AAC haplotype showed significant association with BPH (χ 2 =6.34, P=0.0118). These data suggest that the ESR2 gene may be associated with susceptibility to BPH.

  18. Functional Analysis of Nuclear Estrogen Receptors in Zebrafish Reproduction by Genome Editing Approach.

    PubMed

    Lu, Huijie; Cui, Yong; Jiang, Liwen; Ge, Wei

    2017-07-01

    Estrogens signal through both nuclear and membrane receptors with most reported effects being mediated via the nuclear estrogen receptors (nERs). Although much work has been reported on nERs in the zebrafish, there is a lack of direct genetic evidence for their functional roles and importance in reproduction. To address this issue, we undertook this study to disrupt all three nERs in the zebrafish, namely esr1 (ERα), esr2a (ERβII), and esr2b (ERβI), by the genome-editing technology clustered regularly interspaced short palindromic repeats and its associated nuclease (CRISPR/Cas9). Using this loss-of-function genetic approach, we successfully created three mutant zebrafish lines with each nER knocked out. In addition, we also generated all possible double and triple knockouts of the three nERs. The phenotypes of these mutants in reproduction were analyzed in all single, double, and triple nER knockouts in both females and males. Surprisingly, all three single nER mutant fish lines display normal reproductive development and function in both females and males, suggesting functional redundancy among these nERs. Further analysis of double and triple knockouts showed that nERs, especially Esr2a and Esr2b, were essential for female reproduction, and loss of these two nERs led to an arrest of folliculogenesis at previtellogenic stage II followed by sex reversal from female to male. In addition, the current study also revealed a unique role for Esr2a in follicle cell proliferation and transdifferentiation, follicle growth, and chorion formation. Taken together, this study provides the most comprehensive genetic analysis for differential functions of esr1, esr2a, and esr2b in fish reproduction. Copyright © 2017 Endocrine Society.

  19. Estrogenic activity of natural and synthetic estrogens in human breast cancer cells in culture.

    PubMed Central

    Zava, D T; Blen, M; Duwe, G

    1997-01-01

    We investigated the estrogenic activity of various environmental pollutants (xenobiotics), in particular the xenoestrogen o,p-DDT, and compared their effects with those of endogenous estrogens, phytoestrogens, and mycoestrogens on estrogen receptor binding capacity, induction of estrogen end products, and activation of cell proliferation in estrogen-sensitive human breast cancer cells in monolayer culture. We also quantified the levels of phytoestrogens in extracts of some common foods, herbs, and spices and in human saliva following consumption of a high phytoestrogen food source (soy milk) to compare phytoestrogen abundance and bioavailability relative to the reported xenoestrogen burden in humans. Results show that natural endogenous estrogens, phytoestrogens, mycoestrogens, and xenoestrogens bind estrogen receptor (ER) in intact cells, but demonstrate marked differences in their ability to induce end products of estrogen action and to regulate cell proliferation. All of the different classes of estrogens stimulated cell proliferation at concentrations that half-saturated ER, but only some classes were able to induce estrogen-regulated end products. Genistein, a common phytoestrogen found in soy foods, differed from the xenoestrogen DDT in its effects on cell proliferation and ability to induce estrogen-regulated end products. Moreover, we found that many of the foods, herbs, and spices commonly consumed by humans contain significant amounts of phytoestrogens, and consumption of soy milk, a phytoestrogen-rich food, markedly increases the levels of phytoestrogens in saliva. In conclusion, our in vitro results predict that a diet high in phytoestrogens would significantly reduce the binding of weak xenoestrogens to ER in target tissues in vivo. PMID:9168008

  20. Identification of a Novel LXXLL Motif in α-Actinin 4-spliced Isoform That Is Critical for Its Interaction with Estrogen Receptor α and Co-activators*

    PubMed Central

    Khurana, Simran; Chakraborty, Sharmistha; Zhao, Xuan; Liu, Yu; Guan, Dongyin; Lam, Minh; Huang, Wei; Yang, Sichun; Kao, Hung-Ying

    2012-01-01

    α-Actinins (ACTNs) are a family of proteins cross-linking actin filaments that maintain cytoskeletal organization and cell motility. Recently, it has also become clear that ACTN4 can function in the nucleus. In this report, we found that ACTN4 (full length) and its spliced isoform ACTN4 (Iso) possess an unusual LXXLL nuclear receptor interacting motif. Both ACTN4 (full length) and ACTN4 (Iso) potentiate basal transcription activity and directly interact with estrogen receptor α, although ACTN4 (Iso) binds ERα more strongly. We have also found that both ACTN4 (full length) and ACTN4 (Iso) interact with the ligand-independent and the ligand-dependent activation domains of estrogen receptor α. Although ACTN4 (Iso) interacts efficiently with transcriptional co-activators such as p300/CBP-associated factor (PCAF) and steroid receptor co-activator 1 (SRC-1), the full length ACTN4 protein either does not or does so weakly. More importantly, the flanking sequences of the LXXLL motif are important not only for interacting with nuclear receptors but also for the association with co-activators. Taken together, we have identified a novel extended LXXLL motif that is critical for interactions with both receptors and co-activators. This motif functions more efficiently in a spliced isoform of ACTN4 than it does in the full-length protein. PMID:22908231

  1. Structure-based Understanding of Binding Affinity and Mode of Estrogen Receptor α Agonists and Antagonists.

    EPA Science Inventory

    The flexible hydrophobic ligand binding pocket (LBP) of estrogen receptor α (ERα) allows the binding of a wide variety of endocrine disruptors. Upon ligand binding, the LBP reshapes around the contours of the ligand and stabilizes the complex by complementary hydrophobic interact...

  2. Structure-Based Understanding of Binding Affinity and Mode of Estrogen Receptor α Agonists and Antagonists

    EPA Science Inventory

    The flexible hydrophobic ligand binding pocket (LBP) of estrogen receptor α (ERα) allows the binding of a wide variety of endocrine disruptors. Upon ligand binding, the LBP reshapes around the contours of the ligand and stabilizes the complex by complementary hydrophobic interact...

  3. G protein-coupled estrogen receptor 1/G protein-coupled receptor 30 localizes in the plasma membrane and traffics intracellularly on cytokeratin intermediate filaments.

    PubMed

    Sandén, Caroline; Broselid, Stefan; Cornmark, Louise; Andersson, Krister; Daszkiewicz-Nilsson, Joanna; Mårtensson, Ulrika E A; Olde, Björn; Leeb-Lundberg, L M Fredrik

    2011-03-01

    G protein-coupled receptor 30 [G protein-coupled estrogen receptor 1 (GPER1)], has been introduced as a membrane estrogen receptor and a candidate cancer biomarker and therapeutic target. However, several questions surround the subcellular localization and signaling of this receptor. In native cells, including mouse myoblast C(2)C(12) cells, Madin-Darby canine kidney epithelial cells, and human ductal breast epithelial tumor T47-D cells, G-1, a GPER1 agonist, and 17β-estradiol stimulated GPER1-dependent cAMP production, a defined plasma membrane (PM) event, and recruitment of β-arrestin2 to the PM. Staining of fixed and live cells showed that GPER1 was localized both in the PM and on intracellular structures. One such intracellular structure was identified as cytokeratin (CK) intermediate filaments, including those composed of CK7 and CK8, but apparently not endoplasmic reticulum, Golgi, or microtubules. Reciprocal coimmunoprecipitation of GPER1 and CKs confirmed an association of these proteins. Live staining also showed that the PM receptors constitutively internalize apparently to reach CK filaments. Receptor localization was supported using FLAG- and hemagglutinin-tagged GPER1. We conclude that GPER1-mediated stimulation of cAMP production and β-arrestin2 recruitment occur in the PM. Furthermore, the PM receptors constitutively internalize and localize intracellularly on CK. This is the first observation that a G protein-coupled receptor is capable of associating with intermediate filaments, which may be important for GPER1 regulation in epithelial cells and the relationship of this receptor to cancer.

  4. Evidence for estrogen receptor beta-selective activity of Vitex agnus-castus and isolated flavones.

    PubMed

    Jarry, Hubertus; Spengler, Barbara; Porzel, Andrea; Schmidt, Juergen; Wuttke, Wolfgang; Christoffel, Volker

    2003-10-01

    Recent cell culture experiments indicated that extracts of Vitex agnus-castus (VAC) may contain yet unidentified phytoestrogens. Estrogenic actions are mediated via estrogen receptors (ER). To investigate whether VAC compounds bind to the currently known isoforms ERalpha or ERss, ligand binding assays (LBA) were performed. Subtype specific ER-LBA revealed a binding of VAC to ERss only. To isolate the ERss-selective compounds, the extract was fractionated by bio-guidance. The flavonoid apigenin was isolated and identified as the most active ERss-selective phytoestrogen in VAC. Other isolated compounds were vitexin and penduletin. These data demonstrate that the phytoestrogens in VAC are ERss-selective.

  5. G protein-coupled estrogen receptor inhibits the P2Y receptor-mediated Ca(2+) signaling pathway in human airway epithelia.

    PubMed

    Hao, Yuan; Chow, Alison W; Yip, Wallace C; Li, Chi H; Wan, Tai F; Tong, Benjamin C; Cheung, King H; Chan, Wood Y; Chen, Yangchao; Cheng, Christopher H; Ko, Wing H

    2016-08-01

    P2Y receptor activation causes the release of inflammatory cytokines in the bronchial epithelium, whereas G protein-coupled estrogen receptor (GPER), a novel estrogen (E2) receptor, may play an anti-inflammatory role in this process. We investigated the cellular mechanisms underlying the inhibitory effect of GPER activation on the P2Y receptor-mediated Ca(2+) signaling pathway and cytokine production in airway epithelia. Expression of GPER in primary human bronchial epithelial (HBE) or 16HBE14o- cells was confirmed on both the mRNA and protein levels. Stimulation of HBE or 16HBE14o- cells with E2 or G1, a specific agonist of GPER, attenuated the nucleotide-evoked increases in [Ca(2+)]i, whereas this effect was reversed by G15, a GPER-specific antagonist. G1 inhibited the secretion of two proinflammatory cytokines, interleukin (IL)-6 and IL-8, in cells stimulated by adenosine 5'-(γ-thio)triphosphate (ATPγS). G1 stimulated a real-time increase in cAMP levels in 16HBE14o- cells, which could be inhibited by adenylyl cyclase inhibitors. The inhibitory effects of E2 or G1 on P2Y receptor-induced increases in Ca(2+) were reversed by treating the cells with a protein kinase A (PKA) inhibitor. These results demonstrated that the inhibitory effects of G1 or E2 on P2Y receptor-mediated Ca(2+) mobilization and cytokine secretion were due to GPER-mediated activation of a cAMP-dependent PKA pathway. This study has reported, for the first time, the expression and function of GPER as an anti-inflammatory component in human bronchial epithelia, which may mediate through its opposing effects on the pro-inflammatory pathway activated by the P2Y receptors in inflamed airway epithelia.

  6. Estrogen receptors in gastric cancer: Advances and perspectives.

    PubMed

    Ur Rahman, Muhammad Saif; Cao, Jiang

    2016-02-28

    Worldwide, gastric cancer is one of the most common malignancies with high mortality. Various aspects of the development and progression of gastric cancer continue to be extensively investigated in order to further our understanding and provide more effective means for the prevention, diagnosis, and treatment of the disease. Estrogen receptors (ERs) are steroid hormone receptors that regulate cellular activities in many physiological and pathological processes in different tissues. There are two distinct forms of ERs, namely ERα and ERβ, with several alternative-splicing isoforms for each. They show distinct tissue distribution patterns and exert different biological functions. Dysregulation of ERs has been found to be associated closely with many diseases, including cancer. A number of studies have been conducted to investigate the role of ERs in gastric cancer, the possible mechanisms underlying these roles, and the clinical relevance of deregulated ERs in gastric cancer patients. To date, inconsistent associations of different ERs with gastric cancer have been reported. These inconsistencies may be caused by variations in in vitro cell models and clinical samples, including assay conditions and protocols with regard to different forms of ERs. Given the potential of the deregulated ERs as diagnostic/prognostic markers or therapeutic targets for gastric cancer, it will be important to identify/confirm the association of each ER isoform with gastric cancer, to determine the specific roles and interactions that these individual ER isoforms play under specific conditions in the development and/or progression of gastric cancer, and to elucidate precisely these mechanisms. In this review, we summarize the achievements from early ER studies in gastric cancer to the most up-to-date discoveries, with an effort to provide a comprehensive understanding of the role of ERs roles in gastric cancer and its possible mechanisms. Furthermore, we propose directions for future

  7. Synthesis and characterization of iodinated tetrahydroquinolines targeting the G protein-coupled estrogen receptor GPR30.

    PubMed

    Ramesh, Chinnasamy; Nayak, Tapan K; Burai, Ritwik; Dennis, Megan K; Hathaway, Helen J; Sklar, Larry A; Prossnitz, Eric R; Arterburn, Jeffrey B

    2010-02-11

    A series of iodo-substituted tetrahydro-3H-cyclopenta[c]quinolines was synthesized as potential targeted imaging agents for the G protein-coupled estrogen receptor GPR30. The affinity and specificity of binding to GPR30 versus the classical estrogen receptors ER alpha/beta and functional responses associated with ligand-binding were determined. Selected iodo-substituted tetrahydro-3H-cyclopenta[c]quinolines exhibited IC(50) values lower than 20 nM in competitive binding studies with GPR30-expressing human endometrial cancer cells. These compounds functioned as antagonists of GPR30 and blocked estrogen-induced PI3K activation and calcium mobilization. The tributylstannyl precursors of selected compounds were radiolabeled with (125)I using the iodogen method. In vivo biodistribution studies in female ovariectomized athymic (NCr) nu/nu mice bearing GPR30-expressing human endometrial tumors revealed GPR30-mediated uptake of the radiotracer ligands in tumor, adrenal, and reproductive organs. Biodistribution and quantitative SPECT/CT studies revealed structurally related differences in the pharmacokinetic profiles, target tissue uptake, and metabolism of the radiolabeled compounds as well as differences in susceptibility to deiodination. The high lipophilicity of the compounds adversely affects the in vivo biodistribution and clearance of these radioligands and suggests that further optimization of this parameter may lead to improved targeting characteristics.

  8. Estrogens and aging skin.

    PubMed

    Thornton, M Julie

    2013-04-01

    Estrogen deficiency following menopause results in atrophic skin changes and acceleration of skin aging. Estrogens significantly modulate skin physiology, targeting keratinocytes, fibroblasts, melanocytes, hair follicles and sebaceous glands, and improve angiogenesis, wound healing and immune responses. Estrogen insufficiency decreases defense against oxidative stress; skin becomes thinner with less collagen, decreased elasticity, increased wrinkling, increased dryness and reduced vascularity. Its protective function becomes compromised and aging is associated with impaired wound healing, hair loss, pigmentary changes and skin cancer.   Skin aging can be significantly delayed by the administration of estrogen. This paper reviews estrogen effects on human skin and the mechanisms by which estrogens can alleviate the changes due to aging. The relevance of estrogen replacement, selective estrogen receptor modulators (SERMs) and phytoestrogens as therapies for diminishing skin aging is highlighted. Understanding estrogen signaling in skin will provide a basis for interventions in aging pathologies.

  9. Estrogen receptor-Beta variants are associated with increased risk of Alzheimer's disease in women with down syndrome.

    PubMed

    Zhao, Qi; Lee, Joseph H; Pang, Deborah; Temkin, Alexis; Park, Naeun; Janicki, Sarah C; Zigman, Warren B; Silverman, Wayne; Tycko, Benjamin; Schupf, Nicole

    2011-01-01

    Genetic variants that affect estrogen activity may influence the risk of Alzheimer's disease (AD). We examined the relation of polymorphisms in the gene for the estrogen receptor-beta (ESR2) to the risk of AD in women with Down syndrome. Two hundred and forty-nine women with Down syndrome, 31-70 years of age and nondemented at baseline, were followed at 14- to 18-month intervals for 4 years. Women were genotyped for 13 single-nucleotide polymorphisms (SNPs) in the ESR2 gene, and their association with AD incidence was examined. Among postmenopausal women, we found a 2-fold increase in the risk of AD for women carrying 1 or 2 copies of the minor allele at 3 SNPs in introns seven (rs17766755) and six (rs4365213 and rs12435857) and 1 SNP in intron eight (rs4986938) of ESR2. These findings support a role for estrogen and its major brain receptors in modulating susceptibility to AD in women. Copyright © 2011 S. Karger AG, Basel.

  10. Mechanism of estrogen activation of c-myc oncogene expression.

    PubMed

    Dubik, D; Shiu, R P

    1992-08-01

    The estrogen receptor complex is a known trans-acting factor that regulates transcription of specific genes through an interaction with a specific estrogen-responsive cis-acting element (ERE). In previous studies we have shown that in estrogen-responsive human breast cancer cells estrogen rapidly activates c-myc expression. This activated expression occurs through enhanced transcription and does not require the synthesis of new protein intermediates; therefore, an ERE is present in the human c-myc gene regulatory region. To localize the ERE, constructs containing varying lengths of the c-myc 5'-flanking region ranging from -2327 to +25 (relative to the P1 promoter) placed adjacent to the chloramphenicol acetyl transferase reporter gene (CAT) were prepared. They were used in transient transfection studies in MCF-7 and HeLa cells co-transfected with an estrogen receptor expression vector. These studies reveal that all constructs containing the P2 promoter region exhibited estrogen-regulated CAT expression and that a 116-bp region upstream and encompassing the P2 TATA box is necessary for this activity. Analysis of this 116-bp region failed to identify a cis-acting element with sequences resembling the consensus ERE; however, co-transfection studies with mutant estrogen receptor expression vectors showed that the DNA-binding domain of the receptor is essential for estrogen-regulated CAT gene expression. We have also observed that anti-estrogen receptor complexes can weakly trans-activate from this 116-bp region but fail to do so from the ERE-containing ApoVLDLII-CAT construct. To explain these results we propose a new mechanism of estrogen trans-activation in the c-myc gene promoter.

  11. Development of a recombinant human ovarian (BG1) cell line containing estrogen receptor α and β for improved detection of estrogenic/antiestrogenic chemicals

    PubMed Central

    Brennan, Jennifer C.; Bassal, Arzoo; He, Guochun; Denison, Michael S.

    2016-01-01

    Estrogenic endocrine disrupting chemicals are found in environmental and biological samples, commercial and consumer products, food, and numerous other sources. Given their ubiquitous nature and potential for adverse effects, there is a critical need for rapidly detecting these chemicals. We developed an estrogen-responsive recombinant human ovarian (BG1Luc4E2) cell line recently accepted by the USEPA and OECD as a bioanalytical method to detect estrogen receptor (ER) agonists/antagonists. Unfortunately, these cells appear to contain only one of the two known ER isoforms, ERα but not ERβ, and the differential ligand selectivity of these ERs indicates that the currently accepted screening method only detects a subset of total estrogenic chemicals. To improve the estrogen screening bioassay, BG1Luc4E2 cells were stably transfected with an ERβ expression plasmid and positive clones identified using ERβ-selective ligands (genistein and Br-ERβ-041). A highly responsive clone (BG1LucERβc9) was identified that exhibited greater sensitivity and responsiveness to ERβ-selective ligands than BG1Luc4E2 cells and qRT-PCR confirmed the presence of ERβ expression in these cells. Screening of pesticides and industrial chemicals identified chemicals that preferentially stimulated ERβ-dependent reporter gene expression. Together, these results not only demonstrate the utility of this dual ER recombinant cell line for detecting a broader range of estrogenic chemicals than the current BG1Luc4E2 cell line, but screening with both cell lines allows identification of ERα and ERβ-selective chemicals. PMID:26139245

  12. Timing of androgen receptor disruption and estrogen exposure underlies a spectrum of congenital penile anomalies

    PubMed Central

    Armfield, Brooke A.; Cohn, Martin J.

    2015-01-01

    Congenital penile anomalies (CPAs) are among the most common human birth defects. Reports of CPAs, which include hypospadias, chordee, micropenis, and ambiguous genitalia, have risen sharply in recent decades, but the causes of these malformations are rarely identified. Both genetic anomalies and environmental factors, such as antiandrogenic and estrogenic endocrine disrupting chemicals (EDCs), are suspected to cause CPAs; however, little is known about the temporal window(s) of sensitivity to EDCs, or the tissue-specific roles and downstream targets of the androgen receptor (AR) in external genitalia. Here, we show that the full spectrum of CPAs can be produced by disrupting AR at different developmental stages and in specific cell types in the mouse genital tubercle. Inactivation of AR during a narrow window of prenatal development results in hypospadias and chordee, whereas earlier disruptions cause ambiguous genitalia and later disruptions cause micropenis. The neonatal phase of penile development is controlled by the balance of AR to estrogen receptor α (ERα) activity; either inhibition of androgen or augmentation of estrogen signaling can induce micropenis. AR and ERα have opposite effects on cell division, apoptosis, and regulation of Hedgehog, fibroblast growth factor, bone morphogenetic protein, and Wnt signaling in the genital tubercle. We identify Indian hedgehog (Ihh) as a novel downstream target of AR in external genitalia and show that conditional deletion of Ihh inhibits penile masculinization. These studies reveal previously unidentified cellular and molecular mechanisms by which antiandrogenic and estrogenic signals induce penile malformations and demonstrate that the timing of endocrine disruption can determine the type of CPA. PMID:26598695

  13. VASCULAR ACTIONS OF ESTROGENS: FUNCTIONAL IMPLICATIONS

    PubMed Central

    Miller, Virginia M.; Duckles, Sue P.

    2009-01-01

    The impact of estrogen exposure in preventing or treating cardiovascular disease is controversial. But it is clear that estrogen has important effects on vascular physiology and pathophysiology, with potential therapeutic implications. Therefore, it is the goal of this review to summarize, using an integrated approach, current knowledge of the vascular effects of estrogen, both in humans and in experimental animals. Aspects of estrogen synthesis and receptors, as well as general mechanisms of estrogenic action are reviewed with an emphasis on issues particularly relevant to the vascular system. Recent understanding of the impact of estrogen on mitochondrial function suggests that the longer lifespan of women compared to men may depend in part on the ability of estrogen to decrease production of reactive oxygen species in mitochondria. Mechanisms by which estrogen increases endothelial vasodilator function, promotes angiogenesis and modulates autonomic function are summarized. Key aspects of the relevant pathophysiology of inflammation, atherosclerosis, stroke, migraine and thrombosis are reviewed concerning current knowledge of estrogenic effects. A number of emerging concepts are addressed throughout. These include the importance of estrogenic formulation and route of administration and the impact of genetic polymorphisms, either in estrogen receptors or in enzymes responsible for estrogen metabolism, on responsiveness to hormone treatment. The importance of local metabolism of estrogenic precursors and the impact of timing for initiation of treatment and its duration are also considered. While consensus opinions are emphasized, controversial views are presented in order to stimulate future research. PMID:18579753

  14. EADB: An Estrogenic Activity Database for Assessing ...

    EPA Pesticide Factsheets

    Endocrine-active chemicals can potentially have adverse effects on both humans and wildlife. They can interfere with the body’s endocrine system through direct or indirect interactions with many protein targets. Estrogen receptors (ERs) are one of the major targets, and many endocrine disruptors are estrogenic and affect the normal estrogen signaling pathways. However, ERs can also serve as therapeutic targets for various medical conditions, such as menopausal symptoms, osteoporosis, and ER-positive breast cancer. Because of the decades-long interest in the safety and therapeutic utility of estrogenic chemicals, a large number of chemicals have been assayed for estrogenic activity, but these data exist in various sources and different formats that restrict the ability of regulatory and industry scientists to utilize them fully for assessing risk-benefit. To address this issue, we have developed an Estrogenic Activity Database (EADB; http://www.fda.gov/ScienceResearch/ BioinformaticsTools/EstrogenicActivityDatabaseEADB/default. htm) and made it freely available to the public. EADB contains 18,114 estrogenic activity data points collected for 8212 chemicals tested in 1284 binding, reporter gene, cell proliferation, and in vivo assays in 11 different species. The chemicals cover a broad chemical structure space and the data span a wide range of activities. A set of tools allow users to access EADB and evaluate potential endocrine activity of

  15. A Four-Hour Yeast Bioassay for the Direct Measure of Estrogenic Activity in Wastewater without Sample Extraction, Concentration, or Sterilization

    PubMed Central

    Balsiger, Heather A.; de la Torre, Roberto; Lee, Wen-Yee; Cox, Marc B.

    2010-01-01

    The assay described here represents an improved yeast bioassay that provides a rapid yet sensitive screening method for EDCs with very little hands-on time and without the need for sample preparation. Traditional receptor-mediated reporter assays in yeast were performed twelve to twenty four hours after ligand addition, used colorimetric substrates, and, in many cases, required high, non-physiological concentrations of ligand. With the advent of new chemiluminescent substrates a ligand-induced signal can be detected within thirty minutes using high picomolar to low nanomolar concentrations of estrogen. As a result of the sensitivity (EC50 for estradiol is ~ 0.7 nM) and the very short assay time (2-4 hours) environmental water samples can typically be assayed directly without sterilization, extraction, and concentration. Thus, these assays represent rapid and sensitive approaches for determining the presence of contaminants in environmental samples. As proof of principle, we directly assayed wastewater influent and effluent taken from a wastewater treatment plant in the El Paso, TX area for the presence of estrogenic activity. The data obtained in the four-hour yeast bioassay directly correlated with GC-mass spectrometry analysis of these same water samples. PMID:20074779

  16. Visualizing estrogen receptor-a-expressing neurons using a new ERa-ZsGreen reporter mouse line

    USDA-ARS?s Scientific Manuscript database

    A variety of biological functions of estrogens, including regulation of energy metabolism, are mediated by neurons expressingestrogen receptor-a (ERa) in the brain. However, complex intracellular processes in these ERa-expressing neurons are difficult to unravel, due to the lack of strategy to visua...

  17. Breast density and parenchymal texture measures as potential risk factors for estrogen-receptor positive breast cancer

    NASA Astrophysics Data System (ADS)

    Keller, Brad M.; Chen, Jinbo; Conant, Emily F.; Kontos, Despina

    2014-03-01

    Accurate assessment of a woman's risk to develop specific subtypes of breast cancer is critical for appropriate utilization of chemopreventative measures, such as with tamoxifen in preventing estrogen-receptor positive breast cancer. In this context, we investigate quantitative measures of breast density and parenchymal texture, measures of glandular tissue content and tissue structure, as risk factors for estrogen-receptor positive (ER+) breast cancer. Mediolateral oblique (MLO) view digital mammograms of the contralateral breast from 106 women with unilateral invasive breast cancer were retrospectively analyzed. Breast density and parenchymal texture were analyzed via fully-automated software. Logistic regression with feature selection and was performed to predict ER+ versus ER- cancer status. A combined model considering all imaging measures extracted was compared to baseline models consisting of density-alone and texture-alone features. Area under the curve (AUC) of the receiver operating characteristic (ROC) and Delong's test were used to compare the models' discriminatory capacity for receptor status. The density-alone model had a discriminatory capacity of 0.62 AUC (p=0.05). The texture-alone model had a higher discriminatory capacity of 0.70 AUC (p=0.001), which was not significantly different compared to the density-alone model (p=0.37). In contrast the combined density-texture logistic regression model had a discriminatory capacity of 0.82 AUC (p<0.001), which was statistically significantly higher than both the density-alone (p<0.001) and texture-alone regression models (p=0.04). The combination of breast density and texture measures may have the potential to identify women specifically at risk for estrogen-receptor positive breast cancer and could be useful in triaging women into appropriate risk-reduction strategies.

  18. EADB: An Estrogenic Activity Database for Assessing Potential Endocrine Activity

    EPA Science Inventory

    Endocrine-active chemicals can potentially have adverse effects on both humans and wildlife. They can interfere with the body’s endocrine system through direct or indirect interactions with many protein targets. Estrogen receptors (ERs) are one of the major targets, and many ...

  19. The Oxysterol, 27-Hydroxycholesterol, Links Cholesterol Metabolism to Bone Homeostasis Through Its Actions on the Estrogen and Liver X Receptors

    PubMed Central

    Nelson, Erik R.; DuSell, Carolyn D.; Wang, Xiaojuan; Howe, Matthew K.; Evans, Glenda; Michalek, Ryan D.; Umetani, Michihisa; Rathmell, Jeffrey C.; Khosla, Sundeep; Gesty-Palmer, Diane

    2011-01-01

    Osteoporosis and age-related bone loss are important public health concerns. Therefore, there is a high level of interest in the development of medical interventions and lifestyle changes that reduce the incidence of osteoporosis and age-related bone loss. Decreased bone mineral density is associated with high cholesterol, and patients on statins have increased bone mineral densities, strongly implicating cholesterol as a negative regulator of bone homeostasis. In this study, using both molecular and pharmacological approaches, we have been able to demonstrate that the primary cholesterol metabolite, 27-hydroxycholesterol, through its actions on both estrogen receptors and liver X receptors, decreases osteoblast differentiation and enhances osteoclastogenesis, resulting in increased bone resorbtion in mice. Induction of the short heterodimer partner protein by estrogens in osteoblasts can attenuate the liver X receptor-mediated actions of 27-hydroxycholesterol in bone. These data establish a mechanistic link between cholesterol and bone quality, highlight an unexpected target of estrogens in osteoblasts, and define a signaling axis, the therapeutic exploitation of which is likely to yield novel antiosteoporotic drugs. PMID:21933863

  20. A Rapid, Extensive, and Transient Transcriptional Response to Estrogen Signaling in Breast Cancer Cells

    PubMed Central

    Hah, Nasun; Danko, Charles G.; Core, Leighton; Waterfall, Joshua J.; Siepel, Adam; Lis, John T.; Kraus, W. Lee

    2011-01-01

    Summary We report the immediate effects of estrogen signaling on the transcriptome of breast cancer cells using Global Run-On and sequencing (GRO-seq). The data were analyzed using a new bioinformatic approach that allowed us to identify transcripts directly from the GRO-seq data. We found that estrogen signaling directly regulates a strikingly large fraction of the transcriptome in a rapid, robust, and unexpectedly transient manner. In addition to protein coding genes, estrogen regulates the distribution and activity of all three RNA polymerases, and virtually every class of non-coding RNA that has been described to date. We also identified a large number of previously undetected estrogen-regulated intergenic transcripts, many of which are found proximal to estrogen receptor binding sites. Collectively, our results provide the most comprehensive measurement of the primary and immediate estrogen effects to date and a resource for understanding rapid signal-dependent transcription in other systems. PMID:21549415

  1. Estrogens, Neuroinflammation, and Neurodegeneration

    PubMed Central

    Villa, Alessandro; Vegeto, Elisabetta; Poletti, Angelo

    2016-01-01

    Inflammatory activation of microglia is a hallmark of several disorders of the central nervous system. In addition to protecting the brain against inflammatory insults, microglia are neuroprotective and play a significant role in maintaining neuronal connectivity, but the prolongation of an inflammatory status may limit the beneficial functions of these immune cells. The finding that estrogen receptors are present in monocyte-derived cells and that estrogens prevent and control the inflammatory response raise the question of the role that this sex steroid plays in the manifestation and progression of pathologies that have a clear sex difference in prevalence, such as multiple sclerosis, Parkinson's disease, and Alzheimer's disease. The present review aims to provide a critical review of the current literature on the actions of estrogen in microglia and on the involvement of estrogen receptors in the manifestation of selected neurological disorders. This current understanding highlights a research area that should be expanded to identify appropriate replacement therapies to slow the progression of such diseases. PMID:27196727

  2. Conditional expression of constitutively active estrogen receptor {alpha} in chondrocytes impairs longitudinal bone growth in mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ikeda, Kazuhiro; Tsukui, Tohru; Imazawa, Yukiko

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer Conditional transgenic mice expressing constitutively active estrogen receptor {alpha} (caER{alpha}) in chondrocytes were developed. Black-Right-Pointing-Pointer Expression of caER{alpha} in chondrocytes impaired longitudinal bone growth in mice. Black-Right-Pointing-Pointer caER{alpha} affects chondrocyte proliferation and differentiation. Black-Right-Pointing-Pointer This mouse model is useful for understanding the physiological role of ER{alpha}in vivo. -- Abstract: Estrogen plays important roles in the regulation of chondrocyte proliferation and differentiation, which are essential steps for longitudinal bone growth; however, the mechanisms of estrogen action on chondrocytes have not been fully elucidated. In the present study, we generated conditional transgenic mice, designated as caER{alpha}{sup ColII}, expressing constitutively activemore » mutant estrogen receptor (ER) {alpha} in chondrocytes, using the chondrocyte-specific type II collagen promoter-driven Cre transgenic mice. caER{alpha}{sup ColII} mice showed retardation in longitudinal growth, with short bone lengths. BrdU labeling showed reduced proliferation of hypertrophic chondrocytes in the proliferating layer of the growth plate of tibia in caER{alpha}{sup ColII} mice. In situ hybridization analysis of type X collagen revealed that the maturation of hypertrophic chondrocytes was impaired in caER{alpha}{sup ColII} mice. These results suggest that ER{alpha} is a critical regulator of chondrocyte proliferation and maturation during skeletal development, mediating longitudinal bone growth in vivo.« less

  3. Synthetic estrogen derivatives demonstrate the functionality of intracellular GPR30.

    PubMed

    Revankar, Chetana M; Mitchell, Hugh D; Field, Angela S; Burai, Ritwik; Corona, Cesear; Ramesh, Chinnasamy; Sklar, Larry A; Arterburn, Jeffrey B; Prossnitz, Eric R

    2007-08-17

    Estrogen mediates its effects through multiple cellular receptors. In addition to the classical nuclear estrogen receptors (ERalpha and ERbeta), estrogen also signals through the seven-transmembrane G-protein-coupled receptor (GPCR) GPR30. Although estrogen is a cell-permeable ligand, it is often assumed that all GPCRs function solely as cell surface receptors. Our previous results showed that GPR30 appeared to be expressed predominantly in the endoplasmic reticulum. A critical question that arises is whether this localization represents the site of functional receptor. To address this question, we synthesized a collection of cell-permeable and cell-impermeable estrogen derivatives. We hypothesized that if functional GPR30 were expressed at the cell surface, both permeable and impermeable derivatives would show activity. However, if functional GPR30 were predominantly intracellular, like ERalpha, only the permeable ligands should show activity. Cell permeability was assessed using cells expressing ERalpha as a model intracellular estrogen-binding receptor. Our results reveal that despite exhibiting similar binding affinities for GPR30, only the cell-permeable ligands are capable of stimulating rapid calcium mobilization and phosphoinositide 3-kinase (PI3K) activation. We conclude that GPR30 expressed intracellularly is capable of initiating cellular signaling and that there is insufficient GPR30 expressed on the cell surface to initiate signaling in response to impermeable ligands in the cell lines examined. To our knowledge, this is the first definitive demonstration of a functional intracellular transmembrane estrogen receptor.

  4. G-protein coupled estrogen receptor (GPER) inhibits final oocyte maturation in common carp, Cyprinus carpio.

    PubMed

    Majumder, Suravi; Das, Sumana; Moulik, Sujata Roy; Mallick, Buddhadev; Pal, Puja; Mukherjee, Dilip

    2015-01-15

    GPR-30, now named as GPER (G protein-coupled estrogen receptor) was first identified as an orphan receptor and subsequently shown to be required for estrogen-mediated signaling in certain cancer cells. Later studies demonstrated that GPER has the characteristics of a high affinity estrogen membrane receptor on Atlantic croaker and zebra fish oocytes and mediates estrogen inhibition of oocyte maturation in these two distantly related teleost. To determine the broad application of these findings to other teleost, expression of GPER mRNA and its involvement in 17β-estradiol mediated inhibition of oocyte maturation in other cyprinid, Cyprinus carpio was investigated. Carp oocytes at pre-vitellogenic, late-vitellogenic and post-vitellogenic stages of development contained GPER mRNA and its transcribed protein with a maximum at late-vitellogenic oocytes. Ovarian follicular cells did not express GPER mRNA. Carp oocytes GPER mRNA was essentially identical to that found in other perciformes and cyprinid fish oocytes. Both spontaneous and 17,20β-dihydroxy-4-pregnen-3-one (17,20β-P)-induced oocyte maturation in carp was significantly decreased when they were incubated with either E2, or GPER agonist G-1. On the other hand spontaneous oocyte maturation was significantly increased when carp ovarian follicles were incubated with an aromatase inhibitor, fadrozole, GPER antagonist, G-15 and enzymatic removal of the ovarian follicle cell layers. This increase in oocyte maturation was partially reversed by co-treatment with E2. Consistent with previous findings with human and fish GPR30, E2 treatment in carp oocytes caused increase in cAMP production and simultaneously decrease in oocyte maturation, which was inhibited by the addition of 17,20β-P. The results suggest that E2 and GPER play a critical role in regulating re-entry in to meiotic cell cycle in carp oocytes. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. PACE4 is an important driver of ZR-75-1 estrogen receptor-positive breast cancer proliferation and tumor progression.

    PubMed

    Panet, François; Couture, Frédéric; Kwiatkowska, Anna; Desjardins, Roxane; Guérin, Brigitte; Day, Robert

    2017-08-01

    Breast cancer is the most frequent and deadly malignancy in women worldwide. Despite national screening programs combined with new treatments relapse rate remain high and new therapies are needed. From previous work, we identified PACE4, a member of the proprotein convertase (PCs) family of endoproteases, as a novel therapeutic target in prostate cancer. In the present study we asked the question if PACE4 could also be a potential target in breast cancer. In clinical samples of breast adenocarcinoma, we observed a specific overexpression of PACE4 in the estrogen-receptor (ER) positive subtype. We therefore looked for a breast cancer cell line model which would be representative and thus focused on the ZR-75-1 since it both expresses PACE4 and is estrogen-receptor positive. We compared stable knockdowns of furin, PACE4 and PC7 in the estrogen-receptor-positive cell line ZR-75-1 to evaluate their respective contribution to cell growth and tumor progression. PACE4 was the only PC displaying an impact on cell growth. A PACE4 peptide-based inhibitor (C23) was tested and shown to decrease proliferation of ZR-75-1 cells in cell based assays. C23 also had potent effects of tumor progression in vivo on xenografts of the ZR-75-1 cell line in athymic nude mice. Thus, PACE4-silencing and systemic administration of a PACE4 inhibitor resulted in hindered tumor progression with reduction in proliferative indices and increased cell quiescence assessed with biomarkers. Our results suggest that PACE4 is a promising target for estrogen-receptor-positive breast cancer. Copyright © 2017 Elsevier GmbH. All rights reserved.

  6. Synthesis and Characterization of Tricarbonyl-Re/Tc(I) Chelate Probes Targeting the G Protein-Coupled Estrogen Receptor GPER/GPR30

    PubMed Central

    Burai, Ritwik; Ramesh, Chinnasamy; Nayak, Tapan K.; Dennis, Megan K.; Bryant, Bj K.; Prossnitz, Eric R.; Arterburn, Jeffrey B.

    2012-01-01

    The discovery of the G protein-coupled estrogen receptor GPER (also GPR30) and the resulting development of selective chemical probes have revealed new aspects of estrogen receptor biology. The potential clinical relevance of this receptor has been suggested from numerous studies that have identified GPER expression in breast, endometrial, ovarian and other cancers. Thus GPER can be considered a candidate biomarker and target for non-invasive imaging and therapy. We have designed and synthesized a series of organometallic tricarbonyl-rhenium complexes conjugated to a GPER-selective small molecule derived from tetrahydro-3H-cyclopenta[c]quinoline. The activity and selectivity of these chelates in GPER-mediated signaling pathways were evaluated. These results demonstrate that GPER targeting characteristics depend strongly on the structure of the chelate and linkage. Ethanone conjugates functioned as agonists, a 1,2,3-triazole spacer yielded an antagonist, and derivatives with increased steric volume exhibited decreased activities. Promising GPER selectivity was observed, as none of the complexes interacted with the nuclear estrogen receptors. Radiolabeling with technetium-99m in aqueous media was efficient and gave radioligands with high radiochemical yields and purity. These chelates have favorable physicochemical properties, show excellent stability in biologically relevant media, exhibit receptor specificity and are promising candidates for continuing development as diagnostic imaging agents targeting GPER expression in cancer. PMID:23077529

  7. Synthesis, characterization and binding affinities of rhenium(I) thiosemicarbazone complexes for the estrogen receptor (α/β).

    PubMed

    Núñez-Montenegro, Ara; Carballo, Rosa; Vázquez-López, Ezequiel M

    2014-11-01

    The binding affinities towards estrogen receptors (ERs) α and β of a set of thiosemicarbazone ligands (HL(n)) and their rhenium(I) carbonyl complexes [ReX(HL(n))(CO)3] (X=Cl, Br) were determined by a competitive standard radiometric assay with [(3)H]-estradiol. The ability of the coordinated thiosemicarbazone ligands to undergo deprotonation and the lability of the ReX bond were used as a synthetic strategy to obtain [Re(hpy)(L(n))(CO)3] (hpy=3- or 4-hydroxypyridine). The inclusion of the additional hpy ligand endows the new thiosemicarbazonate complexes with an improved affinity towards the estrogen receptors and, consequently, the values of the inhibition constant (Ki) could be determined for some of them. In general, the values of Ki for both ER subtypes suggest an appreciable selectivity towards ERα. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Estrogen-related receptor {alpha} is essential for the expression of antioxidant protection genes and mitochondrial function

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rangwala, Shamina M.; Li, Xiaoyan; Lindsley, Loren

    2007-05-25

    Estrogen-related receptor {alpha} (ERR{alpha}) is an important mediator of mitochondrial biogenesis and function. To investigate the transcriptional network controlling these phenomena, we investigated mitochondrial gene expression in embryonic fibroblasts isolated from ERR{alpha} null mice. Peroxisome proliferator-activated receptor {gamma} coactivator-1{alpha} (PGC-1{alpha}) stimulated mitochondrial gene expression program in control cells, but not in the ERR{alpha} null cells. Interestingly, the induction of levels of mitochondrial oxidative stress protection genes in response to increased PGC-1{alpha} levels was dependent on ERR{alpha}. Furthermore, we found that the PGC-1{alpha}-mediated induction of estrogen-related receptor {gamma} and nuclear respiratory factor 2 (NRF-2), was dependent on the presence of ERR{alpha}.more » Basal levels of NRF-2 were decreased in the absence of ERR{alpha}. The absence of ERR{alpha} resulted in a decrease in citrate synthase enzyme activity in response to PGC-1{alpha} overexpression. Our results indicate an essential role for ERR{alpha} as a key regulator of oxidative metabolism.« less

  9. Response of adult mouse uterus to early disruption of estrogen receptor-alpha signaling is influenced by Krüppel-like factor 9

    USDA-ARS?s Scientific Manuscript database

    Inappropriate early exposure of the hormone-responsive uterus to estrogenic compounds is associated with increased risk for adult reproductive diseases including endometrial cancers. While the dysregulation of estrogen receptor-alpha (ESR1) signaling is a well-acknowledged early event in tumor initi...

  10. Human sex hormone-binding globulin binding affinities of 125 structurally diverse chemicals and comparison with their binding to androgen receptor, estrogen receptor, and α-fetoprotein.

    PubMed

    Hong, Huixiao; Branham, William S; Ng, Hui Wen; Moland, Carrie L; Dial, Stacey L; Fang, Hong; Perkins, Roger; Sheehan, Daniel; Tong, Weida

    2015-02-01

    One endocrine disruption mechanism is through binding to nuclear receptors such as the androgen receptor (AR) and estrogen receptor (ER) in target cells. The concentration of a chemical in serum is important for its entry into the target cells to bind the receptors, which is regulated by the serum proteins. Human sex hormone-binding globulin (SHBG) is the major transport protein in serum that can bind androgens and estrogens and thus change a chemical's availability to enter the target cells. Sequestration of an androgen or estrogen in the serum can alter the chemical elicited AR- and ER-mediated responses. To better understand the chemical-induced endocrine activity, we developed a competitive binding assay using human pregnancy plasma and measured the binding to the human SHBG for 125 structurally diverse chemicals, most of which were known to bind AR and ER. Eighty seven chemicals were able to bind the human SHBG in the assay, whereas 38 chemicals were nonbinders. Binding data for human SHBG are compared with that for rat α-fetoprotein, ER and AR. Knowing the binding profiles between serum and nuclear receptors will improve assessment of a chemical's potential for endocrine disruption. The SHBG binding data reported here represent the largest data set of structurally diverse chemicals tested for human SHBG binding. Utilization of the SHBG binding data with AR and ER binding data could enable better evaluation of endocrine disrupting potential of chemicals through AR- and ER-mediated responses since sequestration in serum could be considered. Published by Oxford University Press on behalf of the Society of Toxicology 2014. This work is written by US Government employees and is in the public domain in the US.

  11. A demonstration of the uncertainty in predicting the estrogenic activity of individual chemicals and mixtures from an in vitro estrogen receptor transcriptional activation assay (T47D-KBluc) to the in vivo uterotrophic assay using oral exposure

    EPA Science Inventory

    In vitro estrogen receptor assays are valuable screening tools for identifying environmental samples and chemicals that display estrogenic activity. However, in vitro potency cannot necessarily be extrapolated to estimates of in vivo potency because in vitro assays are currently...

  12. Effects of ICI 182780 on estrogen receptor expression, fluid absorption and sperm motility in the epididymis of the bonnet monkey

    PubMed Central

    Shayu, Deshpande; Kesava, Chenna CS; Soundarajan, Rama; Rao, A Jagannadha

    2005-01-01

    Background The importance of estrogen in regulation of fluid absorption and sperm maturation in the rodent epididymis has been established from studies on estrogen receptor-alpha knockout mice. However, functional studies on the role of estrogen in primate epididymis have been few. The main objective of this study was therefore to extend these observations and systematically analyze the presence and function of estrogen receptors in modulating the function of the primate epididymis, using the bonnet monkey (Macaca radiata) as a model system. Methods A steroidal estrogen receptor (ER) antagonist, ICI 182780 (ICI), was administered to adult male bonnet monkeys via mini-osmotic pumps for a duration of 30 to 180 days. The expression of key estrogen-regulated genes (ER-alpha, Na-K ATPase alpha-1 and Aquaporin-1) was examined at specific time points. Further, the effect of ICI in modulating fluid reabsorption in efferent ductules was monitored, and critical sperm-maturation parameters were also analyzed. Results Our studies in the bonnet monkey revealed that both ER-alpha and ER-beta were expressed in all the three regions of the epididymis. We observed an increase in ER-alpha mRNA and protein in the caput of ICI-treated monkeys. Steady state mRNA levels of the water-channel protein, Aquaporin-1, was significantly lower in the caput of ICI-treated monkeys compared to controls, whereas the mRNA levels of Na-K ATPase alpha-1 remained unchanged. In vitro incubation of efferent ductules with ICI resulted in two-fold increase in tubular diameter, indicating affected fluid reabsorption capacity. Furthermore, sperm from ICI-treated monkeys were immotile. Conclusion Taken together, our results point to an integral role for estrogen in modulating the functions of the bonnet monkey epididymis. This study also demonstrates possible differences in the epididymal physiology of rodents and non-human primates, and thus underscores the significance of reports such as these, that examine

  13. Effects of ICI 182780 on estrogen receptor expression, fluid absorption and sperm motility in the epididymis of the bonnet monkey.

    PubMed

    Shayu, Deshpande; ChennaKesava, C S; Soundarajan, Rama; Rao, A Jagannadha

    2005-03-02

    The importance of estrogen in regulation of fluid absorption and sperm maturation in the rodent epididymis has been established from studies on estrogen receptor-alpha knockout mice. However, functional studies on the role of estrogen in primate epididymis have been few. The main objective of this study was therefore to extend these observations and systematically analyze the presence and function of estrogen receptors in modulating the function of the primate epididymis, using the bonnet monkey (Macaca radiata) as a model system. A steroidal estrogen receptor (ER) antagonist, ICI 182780 (ICI), was administered to adult male bonnet monkeys via mini-osmotic pumps for a duration of 30 to 180 days. The expression of key estrogen-regulated genes (ER-alpha, Na-K ATPase alpha-1 and Aquaporin-1) was examined at specific time points. Further, the effect of ICI in modulating fluid reabsorption in efferent ductules was monitored, and critical sperm-maturation parameters were also analyzed. Our studies in the bonnet monkey revealed that both ER-alpha and ER-beta were expressed in all the three regions of the epididymis. We observed an increase in ER-alpha mRNA and protein in the caput of ICI-treated monkeys. Steady state mRNA levels of the water-channel protein, Aquaporin-1, was significantly lower in the caput of ICI-treated monkeys compared to controls, whereas the mRNA levels of Na-K ATPase alpha-1 remained unchanged. In vitro incubation of efferent ductules with ICI resulted in two-fold increase in tubular diameter, indicating affected fluid reabsorption capacity. Furthermore, sperm from ICI-treated monkeys were immotile. Taken together, our results point to an integral role for estrogen in modulating the functions of the bonnet monkey epididymis. This study also demonstrates possible differences in the epididymal physiology of rodents and non-human primates, and thus underscores the significance of reports such as these, that examine the physiology of non-human primates

  14. Activation of estrogen receptor signaling by the dioxin-like aryl hydrocarbon receptor agonist, 3,3',4,4',5-Pentachlorobiphenyl (PCB126) in salmon in vitro system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mortensen, Anne Skjetne; Arukwe, Augustine

    2008-03-01

    Available toxicological evidence indicates that environmental contaminants with strong affinity to the aryl hydrocarbon receptor (AhR) have anti-estrogenic properties in both mammalian and non-mammalian in vivo and in vitro studies. The primary objective of the present study was to investigate the interactions between the AhR and estrogen receptor (ER) in salmon in vitro system. Two separate experiments were performed and gene expression patterns were analyzed using real-time PCR, while protein analysis was done by immunoblotting. Firstly, salmon primary hepatocytes were exposed to the dioxin-like PCB126 at 1, 10 and 50 pM and ER agonist nonylphenol (NP) at 5 and 10more » {mu}M, singly or in combination. Our data showed increased levels of ER-mediated gene expression (vitellogenin: Vtg, zona radiata protein: Zr-protein, ER{alpha}, ER{beta} and vigilin) as well as increased cellular ER{alpha} protein levels after treatment with NP and PCB126, singly or in combination. PCB126 treatment alone produced, as expected, increased transcription of AhR nuclear translocator (Arnt), CYP1A1 and AhR repressor (AhRR) mRNA, and these responses were reduced in the presence of NP concentrations. PCB126 exposure alone did not produce significant effect on AhR2{alpha} mRNA but increased (at 1 and 50 pM) and decreased (at 10 pM) AhR2{beta} mRNA below control level. For AhR2{delta} and AhR2{gamma} isotypes, PCB126 (at 1 pM) produced significant decreases (total inhibition for AhR2{gamma}) of mRNA levels but was indifferent at 10 and 50 pM, compared to control. NP exposure alone produced concentration-dependent significant decrease of AhR2{beta} mRNA. In contrast, while 5 {mu}M NP produced an indifferent effect on AhR2{delta} and AhR2{gamma}, 10 {mu}M NP produced significant decrease (total inhibition for AhR2{gamma}) and the presence of NP produced apparent PCB126 concentration-specific modulation of all AhR isotypes. A second experiment was performed to evaluate the involvement of ER

  15. Estrogens and Cognition: Friends or Foes?

    PubMed Central

    Korol, Donna L.; Pisani, Samantha L.

    2015-01-01

    Estrogens are becoming well known for their robust enhancement on cognition particularly for learning and memory that relies upon functioning of the hippocampus and related neural systems. What is also emerging is that estrogen modulation of cognition is not uniform, at times enhancing yet at other times impairing learning. This review explores the bidirectional effects of estrogens on learning from a multiple memory systems view, focusing on the hippocampus and striatum, whereby modulation by estrogens sorts according to task attributes and neural systems engaged during cognition. We highlight our findings that show the ability to solve hippocampus-sensitive tasks typically improves under relatively high estrogen status while the ability to solve striatum-sensitive tasks degrades with estrogen exposures. Though constrained by dose and timing of exposure, these opposing enhancements and impairments of cognition can be observed following treatments with different estrogenic compounds including the hormone estradiol, the isoflavone genistein found in soybeans, and agonists that are selective for specific estrogen receptors, suggesting that activation of a single receptor type is sufficient to produce the observed shifts in learning strategies. Using this multi-dimensional framework will allow us to extend our thinking of the relationship between estrogens and cognition to other brain regions and cognitive functions. PMID:26149525

  16. Evaluation of the Pathogenesis of Tumor Development from Endometriosis by Estrogen Receptor, P53 and Bcl-2 Immunohistochemical Staining

    PubMed Central

    Esmaili, Haidarali; Vahedi, Amir; Mohajeri, Shiva; Mostafidi, Elmira; Azimpouran, Mahzad; Behzad, Mohammad Naghavi

    2016-01-01

    Objective: Endometriosis, one of the most common estrogen dependent gynecological disorders, can present as both benign and malignant disease. The prevalence of tumoral transformation is 0.7-1.6% and the most common tumors are clear cell and endometrioid carcinomas. Unfortunately, the pathogenesis of transformation is unknown. For this purpose, we examined molecular alterations in ovarian endometriosis and endometriosis-associated tumors. Methods: Using the data bank of Alzahra hospital pathology department and paraffin blocks from appropriate cases were identified. Sections were cut and stained for 3 markers: estrogen receptor, P53 and bcl2. Correlations between findings were investigated. Results: Nineteen cases of endometriosis-associated tumor and 19 cases of endometriosis were identified. Staining for bcl2 was documented in 14 of 19 (73.7%) of endometriosis-associated tumor cases and also 7 of 19 (36.8%) endometriosis cases (P=0.02). Only 3 of the 19 (15.8%) endometriosis-associated tumors exhibited positive staining for estrogen receptors, compared with 14 of 19 (73.7%) endometriosis cases (P<0.001). Positive staining for P53 was noted in 5 of 19 (31.6%) endometriosis-associated ovarian tumor samples but was absent in endometriosis samples (0%), (P =0.008). Conclusions: Endometriosis-associated tumors appear to be associated with overexpression of bcl2 and P53 and reduced expression of Estrogen receptor. These finding may help to diagnose tumoral transformation with a background of endometriosis. PMID:28125869

  17. GPR30: a novel therapeutic target in estrogen-related disease.

    PubMed

    Prossnitz, Eric R; Sklar, Larry A; Oprea, Tudor I; Arterburn, Jeffrey B

    2008-03-01

    Estrogen is a crucial hormone in human physiology that regulates a multitude of biological processes. It is also an important target in many diseases such as cancer and skeletal, neurological and immunological conditions. The actions of estrogen have traditionally been ascribed to one of two closely related classical nuclear hormone receptors, ERalpha and ERbeta, which are best characterized for regulating gene expression. Recent studies have revealed the contribution of a novel estrogen receptor GPR30, which belongs to the family of seven-transmembrane G-protein-coupled receptors, to many of the rapid biological responses to estrogen. Many drugs, such as tamoxifen and fulvestrant, which seem to selectively inhibit the activities of the classical estrogen receptors, are in widespread clinical use. However, recent results indicate that these same drugs activate multiple cellular-signaling pathways via GPR30. Unraveling the pharmacological profiles and specificities of ERalpha, ERbeta and GPR30 will be vital for understanding not only the physiological roles of each receptor but also for the development of the next generation of receptor-specific drugs.

  18. Gender-specific effects of endogenous testosterone: female alpha-estrogen receptor-deficient C57Bl/6J mice develop glomerulosclerosis.

    PubMed

    Elliot, S J; Berho, M; Korach, K; Doublier, S; Lupia, E; Striker, G E; Karl, M

    2007-08-01

    Young female mice on a C57Bl/6J (B6) background are considered glomerulosclerosis (GS)-resistant but aging B6 mice develop mild GS. Estrogen deficiency accelerates while estrogen replacement retards GS in young sclerosis-prone oligosyndactyly mutant mice on an ROP background. To explore the effects of sex hormones on glomerular structure and function in the context of gender and genetic background, we studied mice in which the estrogen-receptor (ER) genes alpha- or -beta were deleted (alpha- or betaER knockout (KO)) and crossed into the B6 background. We also studied ovariectomized (Ovx) B6 mice given testosterone. Male and female betaERKO and male alphaERKO mice had no glomerular dysfunction at 9 months of age; however, alphaERKO female mice displayed albuminuria and GS. Ovx prevented glomerular dysfunction in alphaERKO female mice by eliminating endogenous testosterone production while exogenous testosterone induced GS in Ovx B6 mice. Androgen receptor (AR) expression and function was found in microdissected glomeruli and cultured mesangial cells. Testosterone compared to placebo increased both AR expression and TGF-beta1 mRNA levels in glomeruli isolated from female B6 mice. Estrogen deficiency had no deleterious effects on the glomeruli in B6 mice. Our study shows that genetic traits strongly influence the GS-promoting effects of estrogen deficiency while testosterone induces GS in a gender-specific manner.

  19. Xenobiotic interaction with and alteration of channel catfish estrogen receptor.

    PubMed

    Nimrod, A C; Benson, W H

    1997-12-01

    In teleostean in vivo studies, the vitellogenin response to environmental estrogens is not completely predicted by mammalian literature. One possible explanation for differences is heterogeneity of the estrogen receptor (ER) structure between species. Therefore, ER from channel catfish (Ictalurus punctatus) hepatic tissue was characterized by binding affinity for several compounds. Affinity was indirectly measured as potency of the chemical for inhibiting binding of radiolabeled estradiol (E2) to specific binding sites. The order of potency among therapeutic chemicals was ethinylestradiol > unlabeled E2 = diethylstilbestrol > mestranol > tamoxifen > testosterone. Unlabeled E2 had an IC50 of 2.2 nM. Several environmentally relevant chemicals were evaluated in a similar manner and the order of potency established was the o-demethylated metabolite of methoxychlor (MXC) > nonylphenol (NP) > chlordecone > MXC > o,p'-DDT > o,p'-DDE > beta-hexachlorocyclohexane. Demethylated MXC had an IC50 1000-fold greater than that of E2. Of the most potent inhibitors, NP appeared to be a competitive inhibitor for the same binding site as E2, while o-demethylated MXC had a more complex interaction with the receptor protein. ER from nonvitellogenic females was determined to have a Kd value of 1.0 to 1.3 nM. Because E2 has been reported to up-regulate teleostean ER, the hepatic ER population following in vivo xenobiotic exposure was assessed. NP significantly increased ER per milligram hepatic protein almost to the same extent as E2, but did not increase Kd to the same extent as E2.

  20. The G protein-coupled receptor GPR30 inhibits proliferation of estrogen receptor-positive breast cancer cells.

    PubMed

    Ariazi, Eric A; Brailoiu, Eugen; Yerrum, Smitha; Shupp, Heather A; Slifker, Michael J; Cunliffe, Heather E; Black, Michael A; Donato, Anne L; Arterburn, Jeffrey B; Oprea, Tudor I; Prossnitz, Eric R; Dun, Nae J; Jordan, V Craig

    2010-02-01

    The G protein-coupled receptor GPR30 binds 17beta-estradiol (E(2)) yet differs from classic estrogen receptors (ERalpha and ERbeta). GPR30 can mediate E(2)-induced nongenomic signaling, but its role in ERalpha-positive breast cancer remains unclear. Gene expression microarray data from five cohorts comprising 1,250 breast carcinomas showed an association between increased GPR30 expression and ERalpha-positive status. We therefore examined GPR30 in estrogenic activities in ER-positive MCF-7 breast cancer cells using G-1 and diethylstilbestrol (DES), ligands that selectively activate GPR30 and ER, respectively, and small interfering RNAs. In expression studies, E(2) and DES, but not G-1, transiently downregulated both ER and GPR30, indicating that this was ER mediated. In Ca(2+) mobilization studies, GPR30, but not ERalpha, mediated E(2)-induced Ca(2+) responses because E(2), 4-hydroxytamoxifen (activates GPR30), and G-1, but not DES, elicited cytosolic Ca(2+) increases not only in MCF-7 cells but also in ER-negative SKBr3 cells. Additionally, in MCF-7 cells, GPR30 depletion blocked E(2)-induced and G-1-induced Ca(2+) mobilization, but ERalpha depletion did not. Interestingly, GPR30-coupled Ca(2+) responses were sustained and inositol triphosphate receptor mediated in ER-positive MCF-7 cells but transitory and ryanodine receptor mediated in ER-negative SKBr3 cells. Proliferation studies involving GPR30 depletion indicated that the role of GPR30 was to promote SKBr3 cell growth but reduce MCF-7 cell growth. Supporting this, G-1 profoundly inhibited MCF-7 cell growth, potentially via p53 and p21 induction. Further, flow cytometry showed that G-1 blocked MCF-7 cell cycle progression at the G(1) phase. Thus, GPR30 antagonizes growth of ERalpha-positive breast cancer and may represent a new target to combat this disease.

  1. Estrogen and the female heart.

    PubMed

    Knowlton, A A; Korzick, D H

    2014-05-25

    Estrogen has a plethora of effects in the cardiovascular system. Studies of estrogen and the heart span human clinical trials and basic cell and molecular investigations. Greater understanding of cell and molecular responses to estrogens can provide further insights into the findings of clinical studies. Differences in expression and cellular/intracellular distribution of the two main receptors, estrogen receptor (ER) α and β, are thought to account for the specificity and differences in responses to estrogen. Much remains to be learned in this area, but cellular distribution within the cardiovascular system is becoming clearer. Identification of GPER as a third ER has introduced further complexity to the system. 17β-estradiol (E2), the most potent human estrogen, clearly has protective properties activating a signaling cascade leading to cellular protection and also influencing expression of the protective heat shock proteins (HSP). E2 protects the heart from ischemic injury in basic studies, but the picture is more involved in the whole organism and clinical studies. Here the complexity of E2's widespread effects comes into play and makes interpretation of findings more challenging. Estrogen loss occurs primarily with aging, but few studies have used aged models despite clear evidence of differences between the response to estrogen deficiency in adult and aged animals. Thus more work is needed focusing on the effects of aging vs. estrogen loss on the cardiovascular system. Published by Elsevier Ireland Ltd.

  2. Red Clover Aryl Hydrocarbon Receptor (AhR) and Estrogen Receptor (ER) Agonists Enhance Genotoxic Estrogen Metabolism

    PubMed Central

    2017-01-01

    Many women consider botanical dietary supplements (BDSs) as safe alternatives to hormone therapy for menopausal symptoms. However, the effect of BDSs on breast cancer risk is largely unknown. In the estrogen chemical carcinogenesis pathway, P450 1B1 metabolizes estrogens to 4-hydroxylated catechols, which are oxidized to genotoxic quinones that initiate and promote breast cancer. In contrast, P450 1A1 catalyzed 2-hydroxylation represents a detoxification pathway. The current study evaluated the effects of red clover, a popular BDS used for women’s health, and its isoflavones, biochanin A (BA), formononetin (FN), genistein (GN), and daidzein (DZ), on estrogen metabolism. The methoxy estrogen metabolites (2-MeOE1, 4-MeOE1) were measured by LC-MS/MS, and CYP1A1 and CYP1B1 gene expression was analyzed by qPCR. Nonmalignant ER-negative breast epithelial cells (MCF-10A) and ER-positive breast cancer cells (MCF-7) were derived from normal breast epithelial tissue and ER+ breast cancer tissue. Red clover extract (RCE, 10 μg/mL) and isoflavones had no effect on estrogen metabolism in MCF-10A cells. However, in MCF-7 cells, RCE treatments downregulated CYP1A1 expression and enhanced genotoxic metabolism (4-MeOE1/CYP1B1 > 2-MeOE1/CYP1A1). Experiments with the isoflavones showed that the AhR agonists (BA, FN) preferentially induced CYP1B1 expression as well as 4-MeOE1. In contrast, the ER agonists (GN, DZ) downregulated CYP1A1 expression likely through an epigenetic mechanism. Finally, the ER antagonist ICI 182,780 potentiated isoflavone-induced XRE-luciferase reporter activity and reversed GN and DZ induced downregulation of CYP1A1 expression. Overall, these studies show that red clover and its isoflavones have differential effects on estrogen metabolism in “normal” vs breast cancer cells. In breast cancer cells, the AhR agonists stimulate genotoxic metabolism, and the ER agonists downregulate the detoxification pathway. These data may suggest that especially breast

  3. Development of a recombinant human ovarian (BG1) cell line containing estrogen receptor α and β for improved detection of estrogenic/antiestrogenic chemicals.

    PubMed

    Brennan, Jennifer C; Bassal, Arzoo; He, Guochun; Denison, Michael S

    2016-01-01

    Estrogenic endocrine-disrupting chemicals are found in environmental and biological samples, commercial and consumer products, food, and numerous other sources. Given their ubiquitous nature and potential for adverse effects, a critical need exists for rapidly detecting these chemicals. The authors developed an estrogen-responsive recombinant human ovarian (BG1Luc4E2) cell line recently accepted by the US Environmental Protection Agency (USEPA) and Organisation for Economic Co-operation and Development (OECD) as a bioanalytical method to detect estrogen receptor (ER) agonists/antagonists. Unfortunately, these cells appear to contain only 1 of the 2 known ER isoforms, ERα but not ERβ, and the differential ligand selectivity of these ERs indicates that the currently accepted screening method only detects a subset of total estrogenic chemicals. To improve the estrogen screening bioassay, BG1Luc4E2 cells were stably transfected with an ERβ expression plasmid and positive clones identified using ERβ-selective ligands (genistein and Br-ERβ-041). A highly responsive clone (BG1LucERβc9) was identified that exhibited greater sensitivity and responsiveness to ERβ-selective ligands than BG1Luc4E2 cells, and quantitative reverse-transcription polymerase chain reaction confirmed the presence of ERβ expression in these cells. Screening of pesticides and industrial chemicals identified chemicals that preferentially stimulated ERβ-dependent reporter gene expression. Together, these results not only demonstrate the utility of this dual-ER recombinant cell line for detecting a broader range of estrogenic chemicals than the current BG1Luc4E2 cell line, but screening with both cell lines allows identification of ERα- and ERβ-selective chemicals. © 2015 SETAC.

  4. SMILE, a new orphan nuclear receptor SHP-interacting protein, regulates SHP-repressed estrogen receptor transactivation.

    PubMed

    Xie, Yuan-Bin; Lee, Ok-Hee; Nedumaran, Balachandar; Seong, Hyun-A; Lee, Kyeong-Min; Ha, Hyunjung; Lee, In-Kyu; Yun, Yungdae; Choi, Hueng-Sik

    2008-12-15

    SHP (small heterodimer partner) is a well-known NR (nuclear receptor) co-regulator. In the present study, we have identified a new SHP-interacting protein, termed SMILE (SHP-interacting leucine zipper protein), which was previously designated as ZF (Zhangfei) via a yeast two-hybrid system. We have determined that the SMILE gene generates two isoforms [SMILE-L (long isoform of SMILE) and SMILE-S (short isoform of SMILE)]. Mutational analysis has demonstrated that the SMILE isoforms arise from the alternative usage of initiation codons. We have confirmed the in vivo interaction and co-localization of the SMILE isoforms and SHP. Domain-mapping analysis indicates that the entire N-terminus of SHP and the middle region of SMILE-L are involved in this interaction. Interestingly, the SMILE isoforms counteract the SHP repressive effect on the transactivation of ERs (estrogen receptors) in HEK-293T cells (human embryonic kidney cells expressing the large T-antigen of simian virus 40), but enhance the SHP-repressive effect in MCF-7, T47D and MDA-MB-435 cells. Knockdown of SMILE gene expression using siRNA (small interfering RNA) in MCF-7 cells increases ER-mediated transcriptional activity. Moreover, adenovirus-mediated overexpression of SMILE and SHP down-regulates estrogen-induced mRNA expression of the critical cell-cycle regulator E2F1. Collectively, these results indicate that SMILE isoforms regulate the inhibition of ER transactivation by SHP in a cell-type-specific manner and act as a novel transcriptional co-regulator in ER signalling.

  5. Differential and directional estrogenic signaling pathways induced by enterolignans and their precursors

    PubMed Central

    Zhu, Yun; Kawaguchi, Kayoko; Kiyama, Ryoiti

    2017-01-01

    Mammalian lignans or enterolignans are metabolites of plant lignans, an important category of phytochemicals. Although they are known to be associated with estrogenic activity, cell signaling pathways leading to specific cell functions, and especially the differences among lignans, have not been explored. We examined the estrogenic activity of enterolignans and their precursor plant lignans and cell signaling pathways for some cell functions, cell cycle and chemokine secretion. We used DNA microarray-based gene expression profiling in human breast cancer MCF-7 cells to examine the similarities, as well as the differences, among enterolignans, enterolactone and enterodiol, and their precursors, matairesinol, pinoresinol and sesamin. The profiles showed moderate to high levels of correlation (R values: 0.44 to 0.81) with that of estrogen (17β-estradiol or E2). Significant correlations were observed among lignans (R values: 0.77 to 0.97), and the correlations were higher for cell functions related to enzymes, signaling, proliferation and transport. All the enterolignans/precursors examined showed activation of the Erk1/2 and PI3K/Akt pathways, indicating the involvement of rapid signaling through the non-genomic estrogen signaling pathway. However, when their effects on specific cell functions, cell cycle progression and chemokine (MCP-1) secretion were examined, positive effects were observed only for enterolactone, suggesting that signals are given in certain directions at a position closer to cell functions. We hypothesized that, while estrogen signaling is initiated by the enterolignans/precursors examined, their signals are differentially and directionally modulated later in the pathways, resulting in the differences at the cell function level. PMID:28152041

  6. Chronic Exposure to Anabolic Androgenic Steroids Alters Neuronal Function in the Mammalian Forebrain via Androgen Receptor- and Estrogen Receptor-Mediated Mechanisms

    PubMed Central

    Penatti, Carlos A A; Porter, Donna M; Henderson, Leslie P

    2009-01-01

    Anabolic androgenic steroids (AAS) can promote detrimental effects on social behaviors for which γ-aminobutyric acid type A (GABAA) receptor-mediated circuits in the forebrain play a critical role. While all AAS bind to androgen receptors (AR), they may also be aromatized to estrogens and thus potentially impart effects via estrogen receptors (ER). Chronic exposure of wild type male mice to a combination of chemically distinct AAS increased action potential (AP) frequency, selective GABAA receptor subunit mRNAs, and GABAergic synaptic current decay in the medial preoptic area (mPOA). Experiments performed with pharmacological agents and in AR-deficient Tfm mutant mice suggest that the AAS-dependent enhancement of GABAergic transmission in wild type mice is AR-mediated. In AR-deficient mice, the AAS elicited dramatically different effects, decreasing AP frequency, sIPSC amplitude and frequency and the expression of selective GABAA receptor subunit mRNAs. Surprisingly, in the absence of AR signaling, the data indicate that the AAS do not act as ER agonists, but rather suggest a novel in vivo action in which the AAS inhibit aromatase and impair endogenous ER signaling. These results show that the AAS have the capacity to alter neuronal function in the forebrain via multiple steroid signaling mechanisms and suggest that effects of these steroids in the brain will depend not only on the balance of AR- vs. ER-mediated regulation for different target genes, but also on the ability of these drugs to alter steroid metabolism and thus the endogenous steroid milieu. PMID:19812324

  7. Expression of the IGF and the aromatase/estrogen receptor systems in human adrenal tissues from early infancy to late puberty: implications for the development of adrenarche.

    PubMed

    Belgorosky, Alicia; Baquedano, María Sonia; Guercio, Gabriela; Rivarola, Marco A

    2009-03-01

    Adrenarche is a process of postnatal sexual maturation occurring in higher primates, in which there is an increase in the secretion of adrenal androgens. It is the consequence of a process of postnatal organogenesis characterized by the development of a new zone in the adrenal cortex, the zona reticularis (ZR). The mechanism of this phenomenon remains poorly understood, suggesting that it might be a multifactorial event. A relationship between circulating IGF-I, insulin sensitivity, and adrenal androgens has been postulated. Boys and girls have different patterns of changes in insulin sensitivity at puberty, perhaps secondary to differences in the estrogen milieu. Estrogen effects may also play a role in premature adrenarche. Peripheral or local IGF-1 actions could regulate adrenal progenitor cell proliferation and migration. Since adrenal progenitor cells as well as IGF-I and the IGF-R1 are located in the outer zone of the adrenal cortex during childhood and adolescence, this peripheral cell layer, below the capsule, may contain undifferentiated progenitor cells. Therefore, the IGF-R1 signaling pathway might positively modulate the proliferation and migration of adrenal progenitor cell to stimulate the development of adrenal zones, including ZR. However, no evidence of a direct action of IGF-I on ZR was found. In addition, a role for estrogens in the ontogenesis of ZR is suggested by the presence of aromatase (CYP19) in the subcapsular zona glomerulosa and in the adrenal medulla. Estrogens produced locally could act on ZR by interacting with estrogen receptor beta (ERbeta), but not alpha, and membrane estrogen receptor GPR-30. An estradiol-induced increase in DHEA/cortisol ratio was indeed seen in cultures of adrenocortical cells from post-adrenarche adrenals. In summary, several lines of evidence point to the action of multiple factors, such as local adrenal maturational changes and peripheral metabolic signals, on postnatal human adrenal gland ZR formation.

  8. G protein-coupled estrogen receptor (GPER) regulates mammary tumorigenesis and metastasis

    PubMed Central

    Marjon, Nicole A.; Hu, Chelin

    2014-01-01

    The role of 17β-estradiol (E2) in breast cancer development and tumor growth has traditionally been attributed exclusively to the activation of ERα. Although targeted inhibition of ERα is a successful approach for patients with ERα+ breast cancer, many patients fail to respond or become resistant to anti-estrogen therapy. The discovery of the G protein-coupled estrogen receptor (GPER1) suggested an additional mechanism through which E2 could exert its effects in breast cancer. Studies have demonstrated clinical correlations between GPER expression in human breast tumor specimens and increased tumor size, distant metastasis, and recurrence, as well as established a proliferative role for GPER in vitro; however, direct in vivo evidence has been lacking. To this end, a GPER null mutation [GPER knockout (KO)] was introduced, through interbreeding, into a widely used transgenic mouse model of mammary tumorigenesis [MMTV-PyMT (PyMT)]. Early tumor development, assessed by the extent of hyperplasia and proliferation, was not different between GPER wild-type/PyMT (WT/PyMT) and those mice harboring the GPER null mutation (KO/PyMT). However, by 12-13 weeks of age, tumors from KO/PyMT mice were smaller with decreased proliferation compared to those from WT/PyMT mice. Furthermore, tumors from the KO/PyMT mice were of histologically lower grade compared to tumors from their WT counterparts, suggesting less aggressive tumors in the KO/PyMT mice. Finally, KO/PyMT mice displayed dramatically fewer lung metastases compared to WT/PyMT mice. Combined, these data provide the first in vivo evidence that GPER plays a critical role in breast tumor growth and distant metastasis. PMID:25030371

  9. Tyrosine dephosphorylation enhances the therapeutic target activity of epidermal growth factor receptor (EGFR) by disrupting its interaction with estrogen receptor (ER).

    PubMed

    Ma, Shao; Yin, Ning; Qi, Xiaomei; Pfister, Sandra L; Zhang, Mei-Jie; Ma, Rong; Chen, Guan

    2015-05-30

    Protein-protein interactions can increase or decrease its therapeutic target activity and the determining factors involved, however, are largely unknown. Here, we report that tyrosine-dephosphorylation of epidermal growth factor receptor (EGFR) increases its therapeutic target activity by disrupting its interaction with estrogen receptor (ER). Protein tyrosine phosphatase H1 (PTPH1) dephosphorylates the tyrosine kinase EGFR, disrupts its interaction with the nuclear receptor ER, and increases breast cancer sensitivity to small molecule tyrosine kinase inhibitors (TKIs). These effects require PTPH1 catalytic activity and its interaction with EGFR, suggesting that the phosphatase may increase the sensitivity by dephosphorylating EGFR leading to its dissociation with ER. Consistent with this notion, a nuclear-localization defective ER has a higher EGFR-binding activity and confers the resistance to TKI-induced growth inhibition. Additional analysis show that PTPH1 stabilizes EGFR, stimulates the membranous EGFR accumulation, and enhances the growth-inhibitory activity of a combination therapy of TKIs with an anti-estrogen. Since EGFR and ER both are substrates for PTPH1 in vitro and in intact cells, these results indicate that an inhibitory EGFR-ER protein complex can be switched off through a competitive enzyme-substrate binding. Our results would have important implications for the treatment of breast cancer with targeted therapeutics.

  10. Estrogen: The necessary evil for human health, and ways to tame it.

    PubMed

    Patel, Seema; Homaei, Ahmad; Raju, Akondi Butchi; Meher, Biswa Ranjan

    2018-06-01

    Estrogen is a pivotal enzyme for survival and health in both genders, though their quantum, tropism, tissue-specific distribution, and receptor affinity varies with different phases of life. Converted from androgen via aromatase enzyme, this hormone is indispensable to glucose homeostasis, immune robustness, bone health, cardiovascular health, fertility, and neural functions. However, estrogen is at the center of almost all human pathologies as well-infectious, autoimmune, metabolic to degenerative. Both hypo and hyper level of estrogen has been linked to chronic and acute diseases. While normal aging is supposed to lower its level, leading to tissue degeneration (bone, muscle, neural etc.), and metabolite imbalance (glucose, lipid etc.), the increment in inflammatory agents in day-to-day life are enhancing the estrogen (or estrogen mimic) level, fueling 'estrogen dominance'. The resultant excess estrogen is inducing an overexpression of estrogen receptors (ERα and ERβ), harming tissues, leading to autoimmune diseases, and neoplasms. The unprecedented escalation in the polycystic ovary syndrome, infertility, breast cancer, ovary cancer, and gynecomastia cases are indicating that this sensitive hormone is getting exacerbated. This critical review is an effort to analyze the dual, and opposing facets of estrogen, via understanding its crosstalk with other hormones, enzymes, metabolites, and drugs. Why estrogen level correction is no trivial task, and how it can be restored to normalcy by a disciplined lifestyle with wise dietary and selective chemical usage choices has been discussed. Overall, our current state of knowledge does not disclose the full picture of estrogen's pleiotropic importance. Hence, this review should be a resource for general public as well as researchers to work in that direction. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  11. Receptor-based 3D QSAR analysis of estrogen receptor ligands - merging the accuracy of receptor-based alignments with the computational efficiency of ligand-based methods

    NASA Astrophysics Data System (ADS)

    Sippl, Wolfgang

    2000-08-01

    One of the major challenges in computational approaches to drug design is the accurate prediction of binding affinity of biomolecules. In the present study several prediction methods for a published set of estrogen receptor ligands are investigated and compared. The binding modes of 30 ligands were determined using the docking program AutoDock and were compared with available X-ray structures of estrogen receptor-ligand complexes. On the basis of the docking results an interaction energy-based model, which uses the information of the whole ligand-receptor complex, was generated. Several parameters were modified in order to analyze their influence onto the correlation between binding affinities and calculated ligand-receptor interaction energies. The highest correlation coefficient ( r 2 = 0.617, q 2 LOO = 0.570) was obtained considering protein flexibility during the interaction energy evaluation. The second prediction method uses a combination of receptor-based and 3D quantitative structure-activity relationships (3D QSAR) methods. The ligand alignment obtained from the docking simulations was taken as basis for a comparative field analysis applying the GRID/GOLPE program. Using the interaction field derived with a water probe and applying the smart region definition (SRD) variable selection, a significant and robust model was obtained ( r 2 = 0.991, q 2 LOO = 0.921). The predictive ability of the established model was further evaluated by using a test set of six additional compounds. The comparison with the generated interaction energy-based model and with a traditional CoMFA model obtained using a ligand-based alignment ( r 2 = 0.951, q 2 LOO = 0.796) indicates that the combination of receptor-based and 3D QSAR methods is able to improve the quality of the underlying model.

  12. INTERACTION OF PAH-RELATED COMPOUNDS WITH THE ALPHA AND BETA ISOFORMS OF ESTROGEN RECEPTOR. (R826192)

    EPA Science Inventory

    The ability of several 4- and 5-ring polycyclic aromatic hydrocarbons (PAHs), heterocyclic PAHs, and their monohydroxy derivatives to interact with the estrogen receptor (ER) alpha and beta isoforms was examined. Only compounds possessing a hydroxyl group were able to compete wit...

  13. Molecular Cloning, Characterization, and Expression Analysis of an Estrogen Receptor-Related Receptor Homologue in the Cricket, Teleogryllus emma

    PubMed Central

    He, Hui; Xi, Gengsi; Lu, Xiao

    2010-01-01

    The estrogen receptor-related receptors (ERRs) are a group of nuclear receptors that were originally identified on the basis of sequence similarity to estrogen receptors. The three mammalian ERR genes have been implicated in diverse physiological processes ranging from placental development to maintenance of bone density, but the function and regulation of ERRs in invertebrates are not well understood. A homologue of human ERR was isolated from the cricket Teleogryllus emma (Ohmachi and Matsumura) (Orthoptera: Gryllidae). The full-length cDNA of T. emma ERR, termed TeERR, has 1618 base pair (bp) and contains a 5′?-untranslated region of 140 bp and a 3′?-untranslated region of 272 bp. The open reading frame of TeERR encodes a deduced 401 amino acid peptide with a predicted molecular mass of 45.75 kilodaltons. The results of sequence alignments indicate that the TeERR protein shares an overall identity of 65%–82% with other known ERR homologues, and is most closely related to that of Nasonia vitripennis (Hymenoptera: Pteromalidae) and Apis mellifera (Apidae). Real-time quantitative reverse transcription-polymerase chain reaction was performed to compare the TeERR mRNA expression level at the whole body and gonad during T. emma development. The data revealed that TeERR mRNA is differentially expressed during T. emma development, with the highest expression level in embryos and the lowest in the body of late-instar larvae. The levels of TeERR transcripts also varied throughout gonad development; interestingly testicles had higher higher expression levels than ovaries at every development stage. These results suggest that TeERR has potential significance in the regulation of development in T. emma, due to its expression during different developmental periods. PMID:21265615

  14. Rapid effects of dorsal hippocampal G-protein coupled estrogen receptor on learning in female mice.

    PubMed

    Lymer, Jennifer; Robinson, Alana; Winters, Boyer D; Choleris, Elena

    2017-03-01

    Through rapid mechanisms of action, estrogens affect learning and memory processes. It has been shown that 17β-estradiol and an Estrogen Receptor (ER) α agonist enhances performance in social recognition, object recognition, and object placement tasks when administered systemically or infused in the dorsal hippocampus. In contrast, systemic and dorsal hippocampal ERβ activation only promote spatial learning. In addition, 17β-estradiol, the ERα and the G-protein coupled estrogen receptor (GPER) agonists increase dendritic spine density in the CA1 hippocampus. Recently, we have shown that selective systemic activation of the GPER also rapidly facilitated social recognition, object recognition, and object placement learning in female mice. Whether activation the GPER specifically in the dorsal hippocampus can also rapidly improve learning and memory prior to acquisition is unknown. Here, we investigated the rapid effects of infusion of the GPER agonist, G-1 (dose: 50nM, 100nM, 200nM), in the dorsal hippocampus on social recognition, object recognition, and object placement learning tasks in home cage. These paradigms were completed within 40min, which is within the range of rapid estrogenic effects. Dorsal hippocampal administration of G-1 improved social (doses: 50nM, 200nM G-1) and object (dose: 200nM G-1) recognition with no effect on object placement. Additionally, when spatial cues were minimized by testing in a Y-apparatus, G-1 administration promoted social (doses: 100nM, 200nM G-1) and object (doses: 50nM, 100nM, 200nM G-1) recognition. Therefore, like ERα, the GPER in the hippocampus appears to be sufficient for the rapid facilitation of social and object recognition in female mice, but not for the rapid facilitation of object placement learning. Thus, the GPER in the dorsal hippocampus is involved in estrogenic mediation of learning and memory and these effects likely occur through rapid signalling mechanisms. Copyright © 2016 Elsevier Ltd. All rights

  15. Activation of novel estrogen receptor GPER results in inhibition of cardiocyte apoptosis and cardioprotection.

    PubMed

    Li, Wan-Li; Xiang, Wei; Ping, Ye

    2015-08-01

    Several studies have recently demonstrated that G protein-coupled estrogen receptor (GPER) 30 directly binds to estrogen and mediates its action. The aim of the present study was to investigate the effects of GPER on cardiocyte apoptosis following ischemia/reperfusion injury (MIRI) in H9C2 myocardial cells. H9C2 cells were treated with a specific GPER agonist (G1), 17β-estradiol (E2) or the vehicle. The cells were subjected to 20 min of myocardial ischemia followed by 120 min of reperfusion. They were then randomly assigned to three experimental groups: Control, G1, E2. B-cell lymphoma 2 (Bcl-2) and Bcl-2 associated X (Bax) levels were measured, Hoechst 33258 staining was performed to assess apoptosis, and superoxide dismutase (SOD), tumor necrosis factor (TNF)-α and adenosine triphosphatase (ATPase) levels were determined. To test the specificity of G1, GPER-knockout cells were treated with G1 and analyzed as stated above. Compared with the vehicle-treated groups, G1 and E2-treated groups exhibited elevated Bcl-2 levels, decreased Bax levels and cell apoptosis, significantly increased SOD and ATP levels and decreased TNF-α levels following ischemia-reperfusion. However, G1 had no evident effects on the GPER-knockout cells. In conclusion, the present study suggested that GPER activation provided a cardioprotective effect following ischemia-reperfusion by inhibiting cardiocyte apoptosis.

  16. Estrogen synthesis and signaling pathways during ageing: from periphery to brain

    PubMed Central

    Cui, Jie; Shen, Yong; Li, Rena

    2012-01-01

    Estrogens are the primary female sex hormones and play important roles in both reproductive and non-reproductive systems. Estrogens can be synthesized in non-reproductive tissue as liver, heart, muscle, bone and brain. The tissue-specific estrogen synthesis is consistent with a diversity of estrogen actions. Here, we will focus on tissue and cell-specific estrogen synthesis and estrogen receptor signaling. This review will include three parts: (I) tissue and cell-specific estrogen synthesis and metabolism, (II) tissue and cell-specific distribution of estrogen receptors and signaling and (III) tissue-specific estrogen function and related disorders, including cardiovascular diseases, osteoporosis, Alzheimer's disease and Parkinson disease. This comprehensive review provides new insights into estrogens by giving a better understanding of the tissue-specific estrogen effects and their roles in various diseases. PMID:23348042

  17. Kruppel-like Factor 9 is a Negative Regulator of Ligand-dependent Estrogen Receptor Alpha Signaling in Ishikawa Endometrial Adenocarcinoma Cells

    USDA-ARS?s Scientific Manuscript database

    Estrogen (E) and progesterone (P), acting through their respective receptors and other nuclear proteins, exhibit opposing activities in target cells. We previously reported that Krüppel-like factor 9 (KLF9) cooperates with progesterone receptor (PR) to facilitate P-dependent gene transcription in ut...

  18. Estrogen receptor is activated by korean red ginseng in vitro but not in vivo.

    PubMed

    Shim, Myeong Kuk; Lee, Young Joo

    2012-04-01

    Ginseng has been used as a traditional medicine for treatment of many diseases and for general health maintenance in people of all ages. Ginseng is also used to ameliorate menopausal systems. We investigated the estrogenic activity of Korean red ginseng (KRG) in a transient transfection system, using estrogen receptor (ER) and estrogen-responsive luciferase plasmids in MCF-7 cells. The extract activated both ERα and ERβ. KRG modulated the mRNA levels of estrogen-responsive genes such as pS2 and ESR1 and decreased the protein level of ERα. In order to examine in vivo estrogenic activity of KRG, sixteen female Sprague-Dawley rats separated into four groups were studied for nine weeks: non-ovariectomized (OVX) rats treated with olive oil, OVX rats treated with olive oil, OVX rats treated with 17-β-estradiol (E2) in olive oil, and OVX rats treated with KRG extract in olive oil. The experiments were repeated for three times and the data of twelve rats were combined. Body weight of OVX rats was greater than that of sham-operated control rats and was decreased by E2 treatment. Uterine weight increased after E2 treatment compared to OVX rats. However, no difference in body or uterine weight was observed with KRG intake. KRG induced reductions in total cholesterol, low density lipoprotein cholesterol/total cholesterol, high density lipoprotein cholesterol/total cholesterol, and low density lipoprotein cholesterol/high density lipoprotein cholesterol, but not to the same degree as did E2 intake. These results show that KRG does contain estrogenic activity as manifested by in vitro study but the activity is not strong enough to elicit physiological responses.

  19. Estrogen Receptor Is Activated by Korean Red Ginseng In Vitro but Not In Vivo

    PubMed Central

    Shim, Myeong Kuk; Lee, Young Joo

    2012-01-01

    Ginseng has been used as a traditional medicine for treatment of many diseases and for general health maintenance in people of all ages. Ginseng is also used to ameliorate menopausal systems. We investigated the estrogenic activity of Korean red ginseng (KRG) in a transient transfection system, using estrogen receptor (ER) and estrogen-responsive luciferase plasmids in MCF-7 cells. The extract activated both ERα and ERβ. KRG modulated the mRNA levels of estrogen-responsive genes such as pS2 and ESR1 and decreased the protein level of ERα. In order to examine in vivo estrogenic activity of KRG, sixteen female Sprague-Dawley rats separated into four groups were studied for nine weeks: non-ovariectomized (OVX) rats treated with olive oil, OVX rats treated with olive oil, OVX rats treated with 17-β-estradiol (E2) in olive oil, and OVX rats treated with KRG extract in olive oil. The experiments were repeated for three times and the data of twelve rats were combined. Body weight of OVX rats was greater than that of sham-operated control rats and was decreased by E2 treatment. Uterine weight increased after E2 treatment compared to OVX rats. However, no difference in body or uterine weight was observed with KRG intake. KRG induced reductions in total cholesterol, low density lipoprotein cholesterol/total cholesterol, high density lipoprotein cholesterol/total cholesterol, and low density lipoprotein cholesterol/high density lipoprotein cholesterol, but not to the same degree as did E2 intake. These results show that KRG does contain estrogenic activity as manifested by in vitro study but the activity is not strong enough to elicit physiological responses. PMID:23717117

  20. O-GlcNAcylation of Orphan Nuclear Receptor Estrogen-Related Receptor γ Promotes Hepatic Gluconeogenesis.

    PubMed

    Misra, Jagannath; Kim, Don-Kyu; Jung, Yoon Seok; Kim, Han Byeol; Kim, Yong-Hoon; Yoo, Eun-Kyung; Kim, Byung Gyu; Kim, Sunghoon; Lee, In-Kyu; Harris, Robert A; Kim, Jeong-Sun; Lee, Chul-Ho; Cho, Jin Won; Choi, Hueng-Sik

    2016-10-01

    Estrogen-related receptor γ (ERRγ) is a major positive regulator of hepatic gluconeogenesis. Its transcriptional activity is suppressed by phosphorylation signaled by insulin in the fed state, but whether posttranslational modification alters its gluconeogenic activity in the fasted state is not known. Metabolically active hepatocytes direct a small amount of glucose into the hexosamine biosynthetic pathway, leading to protein O-GlcNAcylation. In this study, we demonstrate that ERRγ is O-GlcNAcylated by O-GlcNAc transferase in the fasted state. This stabilizes the protein by inhibiting proteasome-mediated protein degradation, increasing ERRγ recruitment to gluconeogenic gene promoters. Mass spectrometry identifies two serine residues (S317, S319) present in the ERRγ ligand-binding domain that are O-GlcNAcylated. Mutation of these residues destabilizes ERRγ protein and blocks the ability of ERRγ to induce gluconeogenesis in vivo. The impact of this pathway on gluconeogenesis in vivo was confirmed by the observation that decreasing the amount of O-GlcNAcylated ERRγ by overexpressing the deglycosylating enzyme O-GlcNAcase decreases ERRγ-dependent glucose production in fasted mice. We conclude that O-GlcNAcylation of ERRγ serves as a major signal to promote hepatic gluconeogenesis. © 2016 by the American Diabetes Association.

  1. Differential expression of estrogen receptor α and β isoforms in multiple and solitary leiomyomas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shao, Ruyue; Fang, Liaoqiong; Xing, Ruoxi

    Uterine leiomyomas are benign myometrial neoplasms that function as one of the common indications for hysterectomy. Clinical and biological evidences indicate that uterine leiomyomas are estrogen-dependent. Estrogen stimulates cell proliferation through binding to the estrogen receptor (ER), of which both subtypes α and β are present in leiomyomas. Clinically, leiomyomas may be singular or multiple, where the first one is rarely recurring if removed and the latter associated to a relatively young age or genetic predisposition. These markedly different clinical phenotypes indicate that there may different mechanism causing a similar smooth muscle response. To investigate the relative expression of ERαmore » and ERβ in multiple and solitary uterine leiomyomas, we collected samples from 35 Chinese women (multiple leiomyomas n = 20, solitary leiomyoma n = 15) undergoing surgery to remove uterine leiomyomas. ELISA assay was performed to detect estrogen(E{sub 2}) concentration. Quantitative real-time PCR analysis was performed to detect ERα and ERβ mRNA expression. Western blot and immunohistochemical analysis were performed to detect ERα and ERβ protein expression. We found that ERα mRNA and protein levels of in multiple leiomyomas were significantly lower than those of solitary leiomyomas, whereas ERβ mRNA and protein levels in multiple leiomyomas were significantly higher than those in solitary leiomyomas, irrespectively of the menstrual cycle stage. In both multiple and solitary leiomyomas, ERα expression was higher than that of ERβ. E{sub 2} concentration in multiple and solitary leiomyomas correlated with that of ERα expression. ERα was present in nuclus and cytoplasma while estrogen receptor β localized only in nuclei in both multiple and solitary leiomyomas. Our findings suggest that the difference of ERα and ERβ expression between multiple and solitary leiomyomas may be responsible for the course of the disease subtypes. - Highlights:

  2. Comparison of the Effects of the Selective Estrogen Receptor Modulators Ospemifene, Raloxifene, and Tamoxifen on Breast Tissue in Ex Vivo Culture.

    PubMed

    Eigeliene, Natalija; Erkkola, Risto; Härkönen, Pirkko

    2016-01-01

    Explant tissue culture provides a model for studying the direct effects of steroid hormones, their analogs, and novel hormonally active compounds on normal freshly isolated human breast tissues (HBTs). For this purpose, pre- and postmenopausal HBTs can be maintained in this culture system. The results demonstrate that the morphological integrity of HBT explants can be maintained in tissue culture up to 2 weeks and expression of differentiation markers, steroid hormone receptors, proliferation and apoptosis ratios can be evaluated as a response to hormonal stimulation. This chapter describes an ex vivo culture model that we have applied to study the effects of various hormonally active substances, including 17β-estradiol and selective estrogen receptor modulators (SERMs), on normal human breast tissues.

  3. Quantification of Estrogen Receptor Expression in Normal Breast Tissue in Postmenopausal Women With Breast Cancer and Association With Tumor Subtypes.

    PubMed

    Gulbahce, H Evin; Blair, Cindy K; Sweeney, Carol; Salama, Mohamed E

    2017-09-01

    Estrogen exposure is important in the pathogenesis of breast cancer and is a contributing risk factor. In this study we quantified estrogen receptor (ER) alpha expression in normal breast epithelium (NBR) in women with breast cancer and correlated it with breast cancer subtypes. Tissue microarrays were constructed from 204 breast cancer patients for whom normal breast tissue away from tumor was available. Slides stained with ER were scanned and expression in normal terminal duct lobular epithelium was quantitated using computer-assisted image analysis. ER expression in normal terminal duct lobular epithelium of postmenopausal women with breast cancer was significantly associated with estrogen and triple (estrogen, progesterone receptors, and HER2) negative phenotypes. Also increased age at diagnosis was significantly associated with ER expression in NBR. ER positivity in normal epithelium did not vary by tumor size, lymph node status, tumor grade, or stage. On the basis of quantitative image analysis, we confirm that ER expression in NBR increases with age in women with breast cancer, and report for the first time, a significant association between ER expression in NBR with ER-negative and triple-negative cancers in postmenopausal women.

  4. The estrogen receptor antagonist ICI 182,780 can act both as an agonist and an inverse agonist when estrogen receptor α AF-2 is modified

    PubMed Central

    Movérare-Skrtic, Sofia; Börjesson, Anna E.; Farman, Helen H.; Sjögren, Klara; Windahl, Sara H.; Lagerquist, Marie K.; Andersson, Annica; Stubelius, Alexandra; Carlsten, Hans; Gustafsson, Jan-Åke; Ohlsson, Claes

    2014-01-01

    The bone-sparing effect of estrogen is primarily mediated via estrogen receptor (ER) α, which stimulates target gene transcription through two activation functions (AFs), AF-1 in the N-terminal and AF-2 in the ligand-binding domain. It was recently demonstrated that the ER antagonist ICI 182,780 (ICI) acts as an ER agonist in uterus of mice with mutations in the ERα AF-2. To evaluate the estrogen-like effects of ICI in different tissues, ovariectomized wild-type mice and mice with mutations in the ERα AF-2 (ERαAF-20) were treated with ICI, estradiol, or vehicle for 3 wk. Estradiol increased the trabecular and cortical bone mass as well as the uterine weight, whereas it reduced fat mass, thymus weight, and the growth plate height in wild-type but not in ERαAF-20 mice. Although ICI had no effect in wild-type mice, it exerted tissue-specific effects in ERαAF-20 mice. It acted as an ERα agonist on trabecular bone mass and uterine weight, whereas no effect was seen on cortical bone mass, fat mass, or thymus weight. Surprisingly, a pronounced inverse agonistic activity was seen on the growth plate height, resulting in enhanced longitudinal bone growth. In conclusion, ICI uses ERα AF-1 in a tissue-dependent manner in mice lacking ERαAF-2, resulting in no effect, agonistic activity, or inverse agonistic activity. We propose that ERα lacking AF-2 is constitutively active in the absence of ligand in the growth plate, enabling ICI to act as an inverse agonist. PMID:24395795

  5. The estrogen receptor antagonist ICI 182,780 can act both as an agonist and an inverse agonist when estrogen receptor α AF-2 is modified.

    PubMed

    Movérare-Skrtic, Sofia; Börjesson, Anna E; Farman, Helen H; Sjögren, Klara; Windahl, Sara H; Lagerquist, Marie K; Andersson, Annica; Stubelius, Alexandra; Carlsten, Hans; Gustafsson, Jan-Åke; Ohlsson, Claes

    2014-01-21

    The bone-sparing effect of estrogen is primarily mediated via estrogen receptor (ER) α, which stimulates target gene transcription through two activation functions (AFs), AF-1 in the N-terminal and AF-2 in the ligand-binding domain. It was recently demonstrated that the ER antagonist ICI 182,780 (ICI) acts as an ER agonist in uterus of mice with mutations in the ERα AF-2. To evaluate the estrogen-like effects of ICI in different tissues, ovariectomized wild-type mice and mice with mutations in the ERα AF-2 (ERαAF-2(0)) were treated with ICI, estradiol, or vehicle for 3 wk. Estradiol increased the trabecular and cortical bone mass as well as the uterine weight, whereas it reduced fat mass, thymus weight, and the growth plate height in wild-type but not in ERαAF-2(0) mice. Although ICI had no effect in wild-type mice, it exerted tissue-specific effects in ERαAF-2(0) mice. It acted as an ERα agonist on trabecular bone mass and uterine weight, whereas no effect was seen on cortical bone mass, fat mass, or thymus weight. Surprisingly, a pronounced inverse agonistic activity was seen on the growth plate height, resulting in enhanced longitudinal bone growth. In conclusion, ICI uses ERα AF-1 in a tissue-dependent manner in mice lacking ERαAF-2, resulting in no effect, agonistic activity, or inverse agonistic activity. We propose that ERα lacking AF-2 is constitutively active in the absence of ligand in the growth plate, enabling ICI to act as an inverse agonist.

  6. Human sperm liver receptor homolog-1 (LRH-1) acts as a downstream target of the estrogen signaling pathway

    PubMed Central

    Montanaro, Daniela; Santoro, Marta; Carpino, Amalia; Perrotta, Ida; De Amicis, Francesca; Sirianni, Rosa; Rago, Vittoria; Gervasi, Serena; Aquila, Saveria

    2015-01-01

    In the last decade, the study of human sperm anatomy, at molecular level, has revealed the presence of several nuclear protein receptors. In this work, we examined the expression profile and the ultrastructural localization of liver receptor homolog-1 (LRH-1) in human spermatozoa. We evidenced the presence of the receptor by Western blotting and real time-RT-PCR. Furthermore, we used immunogold electron microscopy to investigate the sperm anatomical regions containing LRH-1. The receptor was mainly located in the sperm head, whereas its expression was reduced in the neck and across the tail. Interestingly, we observed the presence of LRH-1 in different stages of testicular germ cell development by immunohistochemistry. In somatic cells, it has been suggested that the LRH-1 pathway is tightly linked with estrogen signaling and the important role of estradiol has been widely studied in sperm cells. To assess the significance of LRH-1 in male gametes and to deepen understanding of the role of estrogens in these cells, we investigated important sperm features such as motility, survival and capacitation. Spermatozoa were treated with 10 nm estradiol and the inhibition of LRH-1 reversed the estradiol stimulatory action. From our data, we discovered that human spermatozoa can be considered a new site of expression for LRH-1, evidencing its role in sperm motility, survival and cholesterol efflux. Furthermore, we may presume that in spermatozoa the LRH-1 effects are closely integrated with the estrogen signaling, supporting LRH-1 as a downstream effector of the estradiol pathway on some sperm functions. PMID:26241668

  7. ESTROGEN INDUCED VITELLOGENIN MRNA AND PROTEIN IN SHEEPSHEAD MINNOW (CYPRINODON VARIEGATUS)

    EPA Science Inventory

    Many environmentally persistent xenobiotic chemicals appear to disrupt normal endocrine function by acting as ligands for endogenous steroid receptors, including the estrogen receptor. Xenobiotics that bind to the estrogen receptor may elicit several effects, one of which is acti...

  8. Relation of epidermal growth factor receptor and estrogen receptor-independent pS2 protein to the malignant transformation of mucinous cystic neoplasms of the pancreas.

    PubMed

    Kirby, R E; Lewandrowski, K B; Southern, J F; Compton, C C; Warshaw, A L

    1995-01-01

    To evaluate the role of epidermal growth factor receptor (EGF-R) and pS2 protein in the evolution of malignancy in mucinous cystic tumors of the pancreas. Mucinous cystic tumors of the pancreas include histologically benign but premalignant mucinous cystic neoplasms and mucinous cystadenocarcinoma. The molecular events leading to transformation from a benign to a malignant mucinous tumor are not known. Overexpression of EGF-R and detection of an estrogen-induced protein (pS2) has been demonstrated in ductal adenocarcinomas of the pancreas, but these factors have not been evaluated in mucinous cystic tumors. Twenty-six mucinous tumors were examined for EGF-R, pS2 protein, and estrogen and progesterone receptors. Eight (61.2%) of 13 malignant tumors exhibited increased expression of EGF-R, whereas EGF-R was not detected in any of the 13 benign tumors (P = .002). The pS2 protein was detected in nine of 11 malignant and 11 of 11 benign tumors (P = .480). Estrogen and progesterone receptors were not detected in the epithelium of either tumor type. The median survival time of the patients with EGF-R-negative tumors was 29.0 months compared with 14.5 months for those with EGF-R-positive tumors, but this difference did not reach significance owing to the small population size. Overexpression of EGF-R in mucinous cystic tumors, as in ductal adenocarcinomas, may be an important feature associated with malignancy and may have prognostic significance. Failure to detect EGF-R in histologically benign epithelium suggests that the upregulation of EGF-R may be important in the evolution of aggressive behavior. The expression of pS2 protein appears to be independent of estrogen and may play a role in the proliferative activity of mucinous tumors. However, pS2 expression is not a feature associated exclusively with malignancy.

  9. The E-screen assay as a tool to identify estrogens: An update on estrogenic environmental pollutants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Soto, A.M.; Sonnenschein, C.; Chung, K.L.

    1995-10-01

    Estrogens are defined by their ability to induce the proliferation of cells of the female genital tract. The wide chemical diversity of estrogenic compounds precludes an accurate prediction of estrogenic activity on the basis of chemical structure. Rodent bioassays are not suited for the large-scale screening of chemicals before their release into the environment because of their cost, complexity, and ethical concerns. The E-SCREEN assay was developed to assess the estrogenicity of environmental chemicals using the proliferative effect of estrogens on their target cells as an end point. This quantitative assay compares the cell number achieved by similar inocula ofmore » MCF-7 cells in the absence of estrogens (negative control) and in the presence of 17{beta}-estradiol (positive control) and a range of concentrations of chemicals suspected to be estrogenic. Among the compounds tested, several {open_quotes}new{close_quotes} estrogens were found; alkylphenols, phthalates, some PCB congeners and hydroxylated PCBs, and the insecticides dieldrin, endosulfan, and toxaphene were estrogenic by the E-SCREEN assay. In addition, these compounds competed with estradiol for binding to the estrogen receptor and increased the levels of progesterone receptor and pS2 in MCF-7 cells, as expected from estrogen mimics. Recombinant human growth factors (bFGF, EGF, IGF-1) and insulin did not increase cell yields. The aims of the work summarized in this paper were (a) to validate the E-SCREEN assay; (b) to screen a variety of chemicals present in the environment to identify those that may be causing reproductive effects in wildlife and humans; (c) to assess whether environmental estrogens may act cumulatively; and finally (d) to discuss the reliability of this and other assays to screen chemicals for their estrogenicity before they are released into the environment. 57 refs., 3 figs., 9 tabs.« less

  10. The role of estrogens for male bone health.

    PubMed

    Ohlsson, Claes; Vandenput, Liesbeth

    2009-06-01

    Sex steroids are important for the growth and maintenance of both the female and the male skeleton. However, the relative contribution of androgens versus estrogens in the regulation of the male skeleton is unclear. Experiments using mice with inactivated sex steroid receptors demonstrated that both activation of the estrogen receptor (ER)alpha and activation of the androgen receptor result in a stimulatory effect on both the cortical and trabecular bone mass in males. ERbeta is of no importance for the skeleton in male mice while it modulates the ERalpha-action on bone in female mice. Previous in vitro studies suggest that the membrane G protein-coupled receptor GPR30 also might be a functional ER. Our in vivo analyses of GPR30-inactivated mice revealed no function of GPR30 for estrogen-mediated effects on bone mass but it is required for normal regulation of the growth plate and estrogen-mediated insulin-secretion. Recent clinical evidence suggests that a threshold exists for estrogen effects on bone in men: rates of bone loss and fracture risk seem to be the highest in men with estradiol levels below this threshold. Taken together, even though these findings do not exclude an important role for testosterone in male skeletal homeostasis, it is now well-established that estrogens are important regulators of bone health in men.

  11. Nonsteroidal Selective Androgen Receptor Modulators and Selective Estrogen Receptor β Agonists Moderate Cognitive Deficits and Amyloid-β Levels in a Mouse Model of Alzheimer’s Disease

    PubMed Central

    2013-01-01

    Decreases of the sex steroids, testosterone and estrogen, are associated with increased risk of Alzheimer’s disease. Testosterone and estrogen supplementation improves cognitive deficits in animal models of Alzheimer’s disease. Sex hormones play a role in the regulation of amyloid-β via induction of the amyloid-β degrading enzymes neprilysin and insulin-degrading enzyme. To mimic the effect of dihydrotestosterone (DHT), we administered a selective androgen receptor agonist, ACP-105, alone and in combination with the selective estrogen receptor β (ERβ) agonist AC-186 to male gonadectomized triple transgenic mice. We assessed long-term spatial memory in the Morris water maze, spontaneous locomotion, and anxiety-like behavior in the open field and in the elevated plus maze. We found that ACP-105 given alone decreases anxiety-like behavior. Furthermore, when ACP-105 is administered in combination with AC-186, they increase the amyloid-β degrading enzymes neprilysin and insulin-degrading enzyme and decrease amyloid-β levels in the brain as well as improve cognition. Interestingly, the androgen receptor level in the brain was increased by chronic treatment with the same combination treatment, ACP-105 and AC-186, not seen with DHT or ACP-105 alone. Based on these results, the beneficial effect of the selective ERβ agonist as a potential therapeutic for Alzheimer’s disease warrants further investigation. PMID:24020966

  12. Effects of repeated 9 and 30-day exposure to extremely low-frequency electromagnetic fields on social recognition behavior and estrogen receptors expression in olfactory bulb of Wistar female rats.

    PubMed

    Bernal-Mondragón, C; Arriaga-Avila, V; Martínez-Abundis, E; Barrera-Mera, B; Mercado-Gómez, O; Guevara-Guzmán, R

    2017-02-01

    We investigated the short- and long-term effects of extremely low-frequency electromagnetic fields (EMF) on social recognition behavior and expression of α- and β-estrogen receptors (ER). Rats were exposed to 60-Hz electromagnetic fields for 9 or 30 days and tested for social recognition behavior. Immunohistochemistry and western blot assays were performed to evaluate α- and β-ER expression in the olfactory bulb of intact, ovariectomized (OVX), and ovariectomized+estradiol (E2) replacement (OVX+E2). Ovariectomization showed impairment of social recognition after 9 days of EMF exposure and a complete recovery after E2 replacement and so did those after 30 days. Short EMF exposure increased expression of β-ER in intact, but not in the others. Longer exposure produced a decrease in intact but an increase in OVX and OVX+E2. Our findings suggest a significant role for β-estrogen receptors and a lack of effect for α-estrogen receptors on a social recognition task. EMF: extremely low frequency electromagnetic fields; ERs: estrogen receptors; OB: olfactory bulb; OVX: ovariectomized; OVX + E 2 : ovariectomized + estradiol replacement; IEI: interexposure interval; β-ER: beta estrogen receptor; E 2 : replacement of estradiol; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; WB: Western blot; PBS: phosphate-buffer saline; PB: phosphate-buffer.

  13. Opioid receptor agonists may favorably affect bone mechanical properties in rats with estrogen deficiency-induced osteoporosis.

    PubMed

    Janas, Aleksandra; Folwarczna, Joanna

    2017-02-01

    The results of epidemiological, clinical, and in vivo and in vitro experimental studies on the effect of opioid analgesics on bone are inconsistent. The aim of the present study was to investigate the effect of morphine (an agonist of opioid receptors), buprenorphine (a partial μ opioid receptor agonist and κ opioid receptor antagonist), and naloxone (an antagonist of opioid receptors) on the skeletal system of female rats in vivo. The experiments were carried out on 3-month-old Wistar rats, divided into two groups: nonovariectomized (intact; NOVX) rats and ovariectomized (OVX) rats. The bilateral ovariectomy was performed 7 days before the start of drug administration. Morphine hydrochloride (20 mg/kg/day s.c.), buprenorphine (0.05 mg/kg/day s.c.), or naloxone hydrochloride dihydrate (2 mg/kg/day s.c.) were administered for 4 weeks to NOVX and OVX rats. In OVX rats, the use of morphine and buprenorphine counteracted the development of osteoporotic changes in the skeletal system induced by estrogen deficiency. Morphine and buprenorphine beneficially affected also the skeletal system of NOVX rats, but the effects were much weaker than those in OVX rats. Naloxone generally did not affect the rat skeletal system. The results confirmed the role of opioid receptors in the regulation of bone remodeling processes and demonstrated, in experimental conditions, that the use of opioid analgesics at moderate doses may exert beneficial effects on the skeletal system, especially in estrogen deficiency.

  14. Epileptogenic effects of G protein-coupled estrogen receptor 1 in the rat pentylenetetrazole kindling model of epilepsy.

    PubMed

    Kurt, Akif Hakan; Bosnak, Mehmet; Inan, Salim Yalcın; Celik, Ahmet; Uremis, Muhammed Mehdi

    2016-02-01

    G protein-coupled estrogen receptor 1 (GPER-1) has been demonstrated in several parts of the brain and may play an important role in estrogen downstream signaling pathway. However, the effects of this receptor on epileptic seizure are not clearly known. Therefore, the effects of GPER-1 agonist, G-1, GPER-1 antagonist, G-15 and the main estrogenic hormone, 17β-estradiol were investigated on seizures and brain tissue oxidative damages induced by pentylenetetrazole (PTZ) in rats. In this study, 30 adult male Wistar albino rats were used. Due to intraperitoneal (ip) injections of a subconvulsant dose of PTZ (35mg/kg) which was repeated 12 times every 48h, chemical kindling occurred and kindling seizure was recorded for 30min. The rats were injected with 17β-estradiol (5μg/kg, ip) or G-1 (5μg/kg, ip), G-15 (5μg/kg, ip), Saline, Ethanol and Dimethyl sulfoxide (DMSO) 30min before each dose of PTZ. Observed seizures were classified between the phase 0-5. Thirty minutes later when the last 12. PTZ administration, all rats were sacrificed and the brain cortex, hippocampus sections were removed and the tissue superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO) levels on these tissues were studied. GPER1 agonist, G-1 and estrogenic hormone, 17β-estradiol significantly increased the development of PTZ kindling the seizures. However, GPER1 antagonist, G-15 did not change the development of PTZ kindling the seizures. In the cortex and hippocampus homogenates, the NO levels after G-1 administration had significantly increased (p<0.05) compared to the PTZ groups but SOD activities and MDA levels demonstrated no difference between the groups. This is the first study that explores that GPER-1 receptors have epileptogenic effect on PTZ-induced kindling rat. GPER1 may mediate the epileptogenic effect of estrogens by changing the oxidative or anti-oxidative parameters in the brain. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences

  15. Estrogen receptor alpha modulates toll-like receptor signaling in murine lupus

    PubMed Central

    Cunningham, Melissa A.; Naga, Osama S.; Eudaly, Jackie G.; Scott, Jennifer L.; Gilkeson, Gary S.

    2013-01-01

    Systemic lupus erythematosus (SLE) is a disease that disproportionately affects females. Despite significant research effort, the mechanisms underlying the female predominance in this disease are largely unknown. Previously, we showed that estrogen receptor alpha knockout (ERαKO) lupus prone female mice had significantly less pathologic renal disease and proteinuria, and significantly prolonged survival. Since autoantibody levels and number and percentage of B/T cells were not significantly impacted by ERα genotype, we hypothesized that the primary benefit of ERα deficiency in lupus nephritis was via modulation of the innate immune response. Using BMDCs and spleen cells/B cells from female wild-type or ERαKO mice, we found that ERαKO-derived cells have a significantly reduced inflammatory response after stimulation with TLR agonists. Our results indicate that the inflammatory response to TLR ligands is significantly impacted by the presence of ERα despite the absence of estradiol, and may partially explain the protective effect of ERα deficiency in lupus-prone animals. PMID:22659029

  16. Systems Biology of Metabolic Regulation by Estrogen Receptor Signaling in Breast Cancer.

    PubMed

    Zhao, Yiru Chen; Madak Erdogan, Zeynep

    2016-03-17

    With the advent of the -omics approaches our understanding of the chronic diseases like cancer and metabolic syndrome has improved. However, effective mining of the information in the large-scale datasets that are obtained from gene expression microarrays, deep sequencing experiments or metabolic profiling is essential to uncover and then effectively target the critical regulators of diseased cell phenotypes. Estrogen Receptor α (ERα) is one of the master transcription factors regulating the gene programs that are important for estrogen responsive breast cancers. In order to understand to role of ERα signaling in breast cancer metabolism we utilized transcriptomic, cistromic and metabolomic data from MCF-7 cells treated with estradiol. In this report we described generation of samples for RNA-Seq, ChIP-Seq and metabolomics experiments and the integrative computational analysis of the obtained data. This approach is useful in delineating novel molecular mechanisms and gene regulatory circuits that are regulated by a particular transcription factor which impacts metabolism of normal or diseased cells.

  17. Development of a bioluminescence resonance energy transfer (BRET) for monitoring estrogen receptor alpha activation

    NASA Astrophysics Data System (ADS)

    Michelini, Elisa; Mirasoli, Mara; Karp, Matti; Virta, Marko; Roda, Aldo

    2004-06-01

    Estrogen receptor (ER) is a ligand-activated transcriptional factor, able to dimerize after activation and to bind specific DNA sequences (estrogen response elements), thus activating gene target transcription. Since ER homo- and hetero-dimerization (giving a-a and a-b isoforms) is a fundamental step for receptor activation, we developed an assay for detecting compounds that induce human ERa homo-dimerization based on bioluminescence resonance energy transfer (BRET). BRET is a non-radiative energy transfer, occurring between a luminescent donor and a fluorescent acceptor, that strictly depends on the closeness between the two proteins and can therefore be used for studying protein-protein interactions. We cloned ERa coding sequence in frame with either a variant of the green fluorescent protein (enhanced yellow fluorescent protein, EYFP) or Renilla luciferase (RLuc). Upon ERa homo-dimerization, BRET process takes place in the presence of the RLuc substrate coelenterazine resulting in EYFP emission at its characteristic wavelength. The ER alpha-Rluc and ER alpha-EYFP fusion proteins were cloned, then the occurrence of BRET in the presence of ER alpha activators was assayed both in vivo, within cells, and in vitro, with purified fusion proteins.

  18. Estrogens and cognition: Friends or foes?: An evaluation of the opposing effects of estrogens on learning and memory.

    PubMed

    Korol, Donna L; Pisani, Samantha L

    2015-08-01

    This article is part of a Special Issue "Estradiol and cognition". Estrogens are becoming well known for their robust enhancement on cognition particularly for learning and memory that relies upon functioning of the hippocampus and related neural systems. What is also emerging is that estrogen modulation of cognition is not uniform, at times enhancing yet at other times impairing learning. This review explores the bidirectional effects of estrogens on learning from a multiple memory systems view, focusing on the hippocampus and striatum, whereby modulation by estrogens sorts according to task attributes and neural systems engaged during cognition. We highlight our findings showing that the ability to solve hippocampus-sensitive tasks typically improves under relatively high estrogen status while the ability to solve striatum-sensitive tasks degrades with estrogen exposures. Though constrained by dose and timing of exposure, these opposing enhancements and impairments of cognition can be observed following treatments with different estrogenic compounds including the hormone estradiol, the isoflavone genistein found in soybeans, and agonists that are selective for specific estrogen receptors, suggesting that activation of a single receptor type is sufficient to produce the observed shifts in learning strategies. Using this multi-dimensional framework will allow us to extend our thinking of the relationship between estrogens and cognition to other brain regions and cognitive functions. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Novel Metal Ion Based Estrogen Mimics for Molecular Imaging

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rajagopalan, Raghavan

    The overall objective of the SBIR Phase I proposal is to prepare and evaluate a new class of {sup 99m}Tc or {sup 94m}Tc containing estrogen-like small molecules ('estrogen mimics') for SPECT or PET molecular imaging of estrogen receptor positive (ER+) tumors. In this approach, the metal ion is integrated into the estrone skeleton by isosteric substitution of a carbon atom in the steroidal structure to give new class of mimics that are topologically similar to the native estrogen (Fig. 1). Although both N{sub 2}S{sub 2} and N{sub 3}S mimics 1 and 2 were considered as target structures, molecular modeling studymore » revealed that the presence of the acetyl group at position-15 in the N{sub 3}S mimic 2 causes steric hinderance toward binding of 2 to SHBG. Therefore, initial efforts were directed at the synthesis and evaluation of the N{sub 2}S{sub 2} mimic 1.« less

  20. Regulation of estrogen receptor beta mRNA in the brain: opposite effects of 17beta-estradiol and the phytoestrogen, coumestrol.

    PubMed

    Patisaul, H B; Whitten, P L; Young, L J

    1999-04-06

    Estrogen receptor alpha (ERalpha) and estrogen receptor beta (ERbeta) are differentially distributed in the brain and likely mediate different estrogen-dependent processes. ERbeta is abundant in the bed nucleus of the stria terminalis, medial preoptic nucleus, paraventricular nucleus of the hypothalamus and the amygdala of the rat. In the paraventricular nucleus, which is devoid of ERalpha, ERbeta is colocalized with the neuropeptides, oxytocin and vasopressin, suggesting a potential functional role for ERbeta in the regulation of these peptides. We examined the regulation of ERbeta mRNA expression in the rat brain by 17beta-estradiol and the phytoestrogen, coumestrol. 17beta-Estradiol treatment decreased ERbeta mRNA in situ hybridization signal by 44.5% in the paraventricular nucleus of the hypothalamus (PVN), but had no effect in the bed nucleus of the stria terminalis (BnST) or the medial preoptic nucleus (MPA). In contrast, dietary exposure to coumestrol increased ERbeta mRNA signal by 47.5% in the PVN but had no effect in the BnST or the MPA. These data demonstrate that like ERalpha, ERbeta is down regulated by estrogen in a region specific manner in the rat brain. Furthermore, exposure to coumestrol may modulate ERbeta-dependent processes by acting as an anti-estrogen at ERbeta. This data contradicts results from cell transfection assays which suggest an estrogenic activity of coumestrol on ERbeta, indicating that the mode of action may be tissue specific, or that metabolism of dietary coumestrol may alter its effects. Because the highest concentrations of phytoestrogens are found in legumes, vegetables and grains, they are most prevalent in vegetarian and traditional Asian diets. Understanding the neuroendocrine effects of phytoestrogens is particularly important now that they are being marketed as a natural alternative to estrogen replacement therapy and sold in highly concentrated pills and powders. Copyright 1999 Elsevier Science B.V.