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Sample records for hormone receptors alpha

  1. Expansion of microsatellite in the thyroid hormone receptor-alpha1 gene linked to increased receptor expression and less aggressive thyroid cancer

    DEFF Research Database (Denmark)

    Onda, Masamitsu; Li, Daisy; Suzuki, Shinichi

    2002-01-01

    PURPOSE: The purpose of this study was to determine whether the length of the THRA1 microsatellite, which resides in a noncoding portion of the thyroid hormone receptor-alpha1 gene, affects receptor expression and is linked to clinicopathological parameters in thyroid cancer. EXPERIMENTAL DESIGN......: In 30 cases of surgically resected sporadic thyroid cancer, the length of the THRA1 microsatellite was determined by DNA sequence analysis, and expression of thyroid hormone receptor-alpha1 was assessed immunohistochemically in thin sections cut from tumor blocks. The length of THRA1 and expression...... of thyroid hormone receptor-alpha1 were also assessed in seven cancer cell lines. Regression analysis was used to gauge the correlation between the size of THRA1 and receptor expression. Multivariate analysis was used to test for links to the clinical parameters of gender, age, histology, stage, nodal...

  2. Desethylamiodarone is a competitive inhibitor of the binding of thyroid hormone to the thyroid hormone alpha 1-receptor protein

    NARCIS (Netherlands)

    van Beeren, H. C.; Bakker, O.; Wiersinga, W. M.

    1995-01-01

    Desethylamiodarone (DEA), the major metabolite of the potent antiarrythmic drug amiodarone, is a non-competitive inhibitor of the binding of thyroid hormone (T3) to the beta 1-thyroid hormone receptor (T3R). In the present study, we investigated whether DEA acts in a similar way with respect to the

  3. Brain glucose utilization in mice with a targeted mutation in the thyroid hormone alpha or beta receptor gene.

    Science.gov (United States)

    Itoh, Y; Esaki, T; Kaneshige, M; Suzuki, H; Cook, M; Sokoloff, L; Cheng, S Y; Nunez, J

    2001-08-14

    Brain glucose utilization is markedly depressed in adult rats made cretinous after birth. To ascertain which subtype of thyroid hormone (TH) receptors, TRalpha1 or TRbeta, is involved in the regulation of glucose utilization during brain development, we used the 2-[(14)C]deoxyglucose method in mice with a mutation in either their TRalpha or TRbeta gene. A C insertion produced a frameshift mutation in their carboxyl terminus. These mutants lacked TH binding and transactivation activities and exhibited potent dominant negative activity. Glucose utilization in the homozygous TRbetaPV mutant mice and their wild-type siblings was almost identical in 19 brain regions, whereas it was markedly reduced in all brain regions of the heterozygous TRalpha1PV mice. These suggest that the alpha1 receptor mediates the TH effects in brain. Inasmuch as local cerebral glucose utilization is closely related to local synaptic activity, we also examined which thyroid hormone receptor is involved in the expression of synaptotagmin-related gene 1 (Srg1), a TH-positively regulated gene involved in the formation and function of synapses [Thompson, C. C. (1996) J. Neurosci. 16, 7832-7840]. Northern analysis showed that Srg1 expression was markedly reduced in the cerebellum of TRalpha(PV/+) mice but not TRbeta(PV/PV) mice. These results show that the same receptor, TRalpha1, is involved in the regulation by TH of both glucose utilization and Srg1 expression.

  4. The silencing mediator of retinoic acid and thyroid hormone receptor (SMRT) corepressor is required for full estrogen receptor alpha transcriptional activity.

    Science.gov (United States)

    Peterson, Theresa J; Karmakar, Sudipan; Pace, Margaret C; Gao, Tong; Smith, Carolyn L

    2007-09-01

    Multiple factors influence estrogen receptor alpha (ERalpha) transcriptional activity. Current models suggest that the silencing mediator of retinoic acid and thyroid hormone receptor (SMRT) corepressor functions within a histone deactylase-containing protein complex that binds to antiestrogen-bound ERalpha and contributes to negative regulation of gene expression. In this report, we demonstrate that SMRT is required for full agonist-dependent ERalpha activation. Chromatin immunoprecipitation assays demonstrate that SMRT, like ERalpha and the SRC-3 coactivator, is recruited to an estrogen-responsive promoter in estrogen-treated MCF-7 cells. Depletion of SMRT, but not histone deacetylases 1 or 3, negatively impacts estradiol-stimulated ERalpha transcriptional activity, while exogenous expression of SMRT's receptor interaction domains blocks ERalpha activity, indicating a functional interaction between this corepressor and agonist-bound ERalpha. Stimulation of estradiol-induced ERalpha activity by SMRT overexpression occurred in HeLa and MCF-7 cells, but not HepG2 cells, indicating that these positive effects are cell type specific. Similarly, the ability of SMRT depletion to promote the agonist activity of tamoxifen was observed for HeLa but not MCF-7 cells. Furthermore, impairment of agonist-stimulated activity by SMRT depletion is specific to ERalpha and not observed for receptors for vitamin D, androgen, or thyroid hormone. Nuclear receptor corepressor (N-CoR) depletion increased the transcriptional activity of all four tested receptors. SMRT is required for full expression of the ERalpha target genes cyclin D1, BCL-2, and progesterone receptor but not pS2, and its depletion significantly attenuated estrogen-dependent proliferation of MCF-7 cells. Taken together, these data indicate that SMRT, in conjunction with gene-specific and cell-dependent factors, is required for positively regulating agonist-dependent ERalpha transcriptional activity.

  5. Effect of neonatal hypothyroidism on prepubertal mouse testis in relation to thyroid hormone receptor alpha 1 (THRα1).

    Science.gov (United States)

    Sarkar, Debarshi; Singh, Shio Kumar

    2017-09-15

    Thyroid hormones (THs) are important for growth and development of many tissues, and altered thyroid status affects various organs and systems. Testis also is considered as a thyroid hormone responsive organ. Though THs play an important role in regulation of testicular steroidogenesis and spermatogenesis, the exact mechanism of this regulation remains poorly understood. The present study, therefore, is designed to examine the effect of neonatal hypothyroidism on prepubertal Parkes (P) strain mice testis in relation to thyroid hormone receptor alpha 1 (THRα1). Hypothyroidism was induced by administration of 6-propyl-2-thiouracil (PTU) in mother's drinking water from birth to day 28; on postnatal day (PND) 21 only pups, and on PND 28, both pups and lactating dams were euthanized. Serum T 3 and T 4 were markedly reduced in pups at PND 28 and in lactating mothers, while serum and intra-testicular testosterone levels were considerably decreased in pups of both age groups. Further, serum and intra-testicular levels of estrogen were significantly increased in hypothyroid mice at PND 28 with concomitant increase in CYP19 expression. Histologically, marked changes were noticed in testes of PTU-treated mice; immunohistochemical and western blot analyses of testes in treated mice also revealed marked decrease in the expression of THRα1 at both age groups. Semiquantitative RT-PCR and western blot analyses also showed reductions in both testicular mRNA and protein levels of SF-1, StAR, CYP11A1 and 3β-HSD in these mice. In conclusion, our results suggest that neonatal hypothyroidism alters localization and expression of THRα1 and impairs testicular steroidogenesis by down-regulating the expression SF-1, thereby affecting spermatogenesis in prepubertal mice. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Identification and consequences of polymorphisms in the thyroid hormone receptor alpha and beta genes

    DEFF Research Database (Denmark)

    Sørensen, Helena Gásdal; van der Deure, Wendy M; Hansen, Pia Skov

    2008-01-01

    SNPs in the 3' untranslated region of THRA were genotyped: a novel SNP (2390A/G) and 1895C/A (rs12939700). In THRB, a synonymous (735C/T; rs3752874) and an intronic SNP (in9-G/A; rs13063628) were genotyped. No associations between SNPs and thyroid hormone levels (total and free 3,3',5-triiodo...

  7. The chicken c-erbA alpha-product induces expression of thyroid hormone-responsive genes in 3,5,3'-triiodothyronine receptor-deficient rat hepatoma cells

    DEFF Research Database (Denmark)

    Muñoz, A; Höppner, W; Sap, J

    1990-01-01

    To determine the capacity of the chicken c-erbA (cTR-alpha) gene product in regulating expression of known thyroid hormone-responsive genes, both the cTR-alpha and the viral v-erbA genes were expressed in FAO cells, a rat hepatoma cell line defective for functional thyroid hormone receptors. Upon...

  8. Alpha-melanocyte stimulating hormone modulates ethanol self-administration in posterior ventral tegmental area through melanocortin-4 receptors.

    Science.gov (United States)

    Shelkar, Gajanan P; Kale, Atmaram D; Singh, Uday; Singru, Praful S; Subhedar, Nishikant K; Kokare, Dadasaheb M

    2015-03-01

    Although the role of alpha-melanocyte stimulating hormone (α-MSH) in alcohol seeking behaviour in rats has been demonstrated, the underlying mechanisms are not understood. Herein, we test the hypothesis that α-MSH might have a permissive effect in promoting the reward action of ethanol. Rats were implanted with cannulae targeted at the posterior ventral tegmental area (pVTA), because the site is sensitive to reinforcing effects of ethanol. These rats were trained to self-administer ethanol in standard two-lever (active/inactive) operant chamber test. Each active lever press resulted in self-administration of 100 nl of ethanol (100-300 mg%) containing solution. Over a period of 7 days, ethanol significantly increased the number of lever presses, which was considered as a measure of reward. Because ethanol at 200 mg% resulted in maximum number of lever presses (∼18-20 lever presses/30-minute session), the dose was employed in further studies. While prior administration of melanocortin (MC) agonists, α-MSH or [Nle4,D-Phe7]-alpha-MSH into pVTA, resulted in an 89% increase in lever presses, the response was attenuated following pre-treatment with MC4 receptors (MC4R) antagonist, HS014. In an immunohistochemical study, the brains of rats that were trained to self-infuse ethanol showed significantly increased α-MSH immunoreactivity in the nucleus accumbens shell, bed nucleus of stria terminalis and arcuate nucleus of the hypothalamus. In the pVTA, α-MSH fibres were found to run close to the dopamine cells, labelled with tyrosine hydroxylase antibodies. We suggest that α-MSH-MC4R system in the pVTA might be a part of the neuroadaptive mechanism underlying ethanol addiction. © 2014 Society for the Study of Addiction.

  9. Modifications of receptor concentrations for adrenaline, steroid hormones, prostaglandin F2alpha and gonadotropins in hypophysis and ovary of dairy cows with ovarian cysts.

    Science.gov (United States)

    Odore, R; Re, G; Badino, P; Donn, A; Vigo, D; Biolatti, B; Girardi, C

    1999-04-01

    Receptor concentrations for adrenaline, steroid hormones, PGF2alpha, LH and FSH were measured in the hypophysis and ovary of dairy cows with ovarian cysts and the results were compared with those of healthy animals. Significant modifications were found in all receptor concentrations, either between follicular and luteal structures or between the hypophyseal and ovarian receptorial status. The correlations between catecholaminergic and steroidal systems have already been demonstrated, particularly those existing between beta-adrenoceptors and steroid hormone receptors. Particular attention has been given to the possibility that a derangement in neurogenic inputs may be at the basis of some ovarian pathologies. The results of the present study suggest that the modifications of the ovarian and hypophyseal receptorial status of healthy and affected cows could play an important role in the pathogenesis of ovarian cysts. Copyright 1999 The Italian Pharmacological Society.

  10. Thyroid hormone receptor alpha (TRa) tissue expression in ductal invasive breast cancer: A study combining quantitative immunohistochemistry with digital slide image analysis.

    Science.gov (United States)

    Charalampoudis, P; Agrogiannis, G; Kontzoglou, K; Kouraklis, G; Sotiropoulos, G C

    2017-08-01

    In breast cancer, hormonal receptors hold promise for developing novel targeted therapies. The thyroid exerts its actions via the thyroid hormone receptors alpha and beta. The clinical significance of the expression of thyroid hormone receptors in breast cancer is unclear. We studied thyroid hormone receptor alpha (TRa) expression in 82 samples from 41 women with ductal invasive breast cancer and no thyroid disease. We performed quantitative immunohistochemistry with digital image analysis and correlated TRa expression with clinicopathological parameters. TRa was expressed in both normal breast epithelium and breast cancer, but expression in breast cancer was significantly lower. TRa was expressed significantly less in larger and grade III tumors. Conversely, breast cancers with lymphovascular invasion showed increased TRa expression compared to cancers without lymphovascular invasion. TRa expression was not significantly different between node-positive and node-negative breast cancers, or among different hormonal profiles and intrinsic subtypes. This is the first-in-human study to combine quantitative immunohistochemistry with image analysis to study TRa expression in women with ductal invasive breast cancer and no clinical or biochemical evidence of thyroid dysfunction. We confirm that TRa is expressed in both normal and malignant breast epithelium and suggest that TRa expression is downregulated during breast carcinogenesis. Larger and higher grade breast cancers demonstrate partial loss in TRa expression. Alterations in TRa expression take place even in the absence of clinical or biochemical thyroid disease. The underlying mechanism of these findings and their potential significance in survival and relapse mandate further research. Copyright © 2017 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

  11. Nitric oxide enhances the sensitivity of alpaca melanocytes to respond to {alpha}-melanocyte-stimulating hormone by up-regulating melanocortin-1 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Yanjun; Cao, Jing; Wang, Haidong; Zhang, Jie; Zhu, Zhiwei; Bai, Rui; Hao, HuanQing; He, Xiaoyan; Fan, Ruiwen [College of Animal Science and Technology, Shanxi Agricultural University, 030801 Taigu, Shanxi (China); Dong, Changsheng, E-mail: cs_dong@sxau.edu.cn [College of Animal Science and Technology, Shanxi Agricultural University, 030801 Taigu, Shanxi (China)

    2010-06-11

    Nitric oxide (NO) and {alpha}-melanocyte-stimulating hormone ({alpha}-MSH) have been correlated with the synthesis of melanin. The NO-dependent signaling of cellular response to activate the hypothalamopituitary proopiomelanocortin system, thereby enhances the hypophysial secretion of {alpha}-MSH to stimulate {alpha}-MSH-receptor responsive cells. In this study we investigated whether an NO-induced pathway can enhance the ability of the melanocyte to respond to {alpha}-MSH on melanogenesis in alpaca skin melanocytes in vitro. It is important for us to know how to enhance the coat color of alpaca. We set up three groups for experiments using the third passage number of alpaca melanocytes: the control cultures were allowed a total of 5 days growth; the UV group cultures like the control group but the melanocytes were then irradiated everyday (once) with 312 mJ/cm{sup 2} of UVB; the UV + L-NAME group is the same as group UV but has the addition of 300 {mu}M L-NAME (every 6 h). To determine the inhibited effect of NO produce, NO produces were measured. To determine the effect of the NO to the key protein and gene of {alpha}-MSH pathway on melanogenesis, the key gene and protein of the {alpha}-MSH pathway were measured by quantitative real-time PCR and Western immunoblotting. The results provide exciting new evidence that NO can enhance {alpha}-MSH pathway in alpaca skin melanocytes by elevated MC1R. And we suggest that the NO pathway may more rapidly cause the synthesis of melanin in alpaca skin under UV, which at that time elevates the expression of MC1R and stimulates the keratinocytes to secrete {alpha}-MSH to enhance the {alpha}-MSH pathway on melanogenesis. This process will be of considerable interest in future studies.

  12. Nitric oxide enhances the sensitivity of alpaca melanocytes to respond to alpha-melanocyte-stimulating hormone by up-regulating melanocortin-1 receptor.

    Science.gov (United States)

    Dong, Yanjun; Cao, Jing; Wang, Haidong; Zhang, Jie; Zhu, Zhiwei; Bai, Rui; Hao, HuanQing; He, Xiaoyan; Fan, Ruiwen; Dong, Changsheng

    2010-06-11

    Nitric oxide (NO) and alpha-melanocyte-stimulating hormone (alpha-MSH) have been correlated with the synthesis of melanin. The NO-dependent signaling of cellular response to activate the hypothalamopituitary proopiomelanocortin system, thereby enhances the hypophysial secretion of alpha-MSH to stimulate alpha-MSH-receptor responsive cells. In this study we investigated whether an NO-induced pathway can enhance the ability of the melanocyte to respond to alpha-MSH on melanogenesis in alpaca skin melanocytes in vitro. It is important for us to know how to enhance the coat color of alpaca. We set up three groups for experiments using the third passage number of alpaca melanocytes: the control cultures were allowed a total of 5 days growth; the UV group cultures like the control group but the melanocytes were then irradiated everyday (once) with 312 mJ/cm(2) of UVB; the UV+L-NAME group is the same as group UV but has the addition of 300 microM L-NAME (every 6h). To determine the inhibited effect of NO produce, NO produces were measured. To determine the effect of the NO to the key protein and gene of alpha-MSH pathway on melanogenesis, the key gene and protein of the alpha-MSH pathway were measured by quantitative real-time PCR and Western immunoblotting. The results provide exciting new evidence that NO can enhance alpha-MSH pathway in alpaca skin melanocytes by elevated MC1R. And we suggest that the NO pathway may more rapidly cause the synthesis of melanin in alpaca skin under UV, which at that time elevates the expression of MC1R and stimulates the keratinocytes to secrete alpha-MSH to enhance the alpha-MSH pathway on melanogenesis. This process will be of considerable interest in future studies. (c) 2010 Elsevier Inc. All rights reserved.

  13. The interaction between menstrual cycle, Tumour Necrosis Factor alpha receptors and sex hormones in healthy non-obese women – results from an observational study

    Directory of Open Access Journals (Sweden)

    Paweł Rzymski

    2014-09-01

    Full Text Available There is growing evidence that TNF-alpha and its two receptors play an important role in hormonal regulation, metabolism, inflammation and cancer. The biological effects of TNF-alpha are mediated by two receptors, p55 and p75. The aim of this study was to analyze serum concentrations of p55 and p75 and hormonal status in healthy women during the normal menstrual cycle. Eight women aged 20–22 with regular menstrual cycles were scheduled for examination on 3[sup]rd[/sup] , 8[sup]th[/sup] , 14[sup]th[/sup] and 25[sup]th [/sup] day of their menstrual cycle. We only observed a positive correlation of p75 subunit with prolactin level (correlation coefficient 0.417; p=0.0116 and negative correlation with insulin level (correlation coefficient -0.35; p=0.032 and HOMA[sub]IR[/sub] insulin resistance index correlation coefficient 0.39; p=0.0185. Furthermore, a negative correlation of p55/p75 ratio with prolactin (correlation coefficient -0.42; p=0.0101 and a positive correlations of p55/p75 ratio with insulin level (correlation coefficient 0.43; p=0.008 and HOMA[sub]IR[/sub] insulin resistance factor correlation coefficient 0.45; p=0.0065 were found.

  14. Placental expression of estrogen receptor beta and its hormone binding variant – comparison with estrogen receptor alpha and a role for estrogen receptors in asymmetric division and differentiation of estrogen-dependent cells

    Directory of Open Access Journals (Sweden)

    Henley Donald C

    2003-04-01

    Full Text Available Abstract During human pregnancy, the production of 17-beta-estradiol (E2 rises steadily to eighty fold at term, and placenta has been found to specifically bind estrogens. We have recently demonstrated the expression of estrogen receptor alpha (ER-alpha protein in human placenta and its localization in villous cytotrophoblast (CT, vascular pericytes, and amniotic fibroblasts. In vitro, E2 stimulated development of large syncytiotrophoblast (ST aggregates. In the present study we utilized ER-beta affinity purified polyclonal (N19:sc6820 and ER-alpha monoclonal (clone h-151 antibodies. Western blot analysis revealed a single ~52 kDa ER-beta band in chorionic villi (CV protein extracts. In CV, strong cytoplasmic ER-beta immunoreactivity was confined to ST. Dual color immunohistochemistry revealed asymmetric segregation of ER-alpha in dividing villous CT cells. Prior to separation, the cell nuclei more distant from ST exhibited high ER-alpha, while cell nuclei associated with ST showed diminution of ER-alpha and appearance of ER-beta. In trophoblast cultures, development of ST aggregates was associated with diminution of ER-alpha and appearance of ER-beta immunoreactivity. ER-beta was also detected in endothelial cells, amniotic epithelial cells and fibroblasts, extravillous trophoblast (nuclear and cytoplasmic and decidual cells (cytoplasmic only. In addition, CFK-E12 (E12 and CWK-F12 (F12 monoclonal antibodies, which recognize ~64 kDa ER-beta with hormone binding domain, showed nuclear-specific reactivity with villous ST, extravillous trophoblast, and amniotic epithelium and fibroblasts. Western blot analysis indicated abundant expression of a ~64 kDa ER-beta variant in trophoblast cultures, significantly higher when compared to the chorionic villi and freshly isolated trophoblast cell protein extracts. This is the first report on ER-beta expression in human placenta and cultured trophoblast. Our data indicate that during trophoblast

  15. Identification of a hormone-regulated dynamic nuclear actin network associated with estrogen receptor alpha in human breast cancer cell nuclei.

    Science.gov (United States)

    Ambrosino, Concetta; Tarallo, Roberta; Bamundo, Angela; Cuomo, Danila; Franci, Gianluigi; Nassa, Giovanni; Paris, Ornella; Ravo, Maria; Giovane, Alfonso; Zambrano, Nicola; Lepikhova, Tatiana; Jänne, Olli A; Baumann, Marc; Nyman, Tuula A; Cicatiello, Luigi; Weisz, Alessandro

    2010-06-01

    Estrogen receptor alpha (ERalpha) is a modular protein of the steroid/nuclear receptor family of transcriptional regulators that upon binding to the hormone undergoes structural changes, resulting in its nuclear translocation and docking to specific chromatin sites. In the nucleus, ERalpha assembles in multiprotein complexes that act as final effectors of estrogen signaling to the genome through chromatin remodeling and epigenetic modifications, leading to dynamic and coordinated regulation of hormone-responsive genes. Identification of the molecular partners of ERalpha and understanding their combinatory interactions within functional complexes is a prerequisite to define the molecular basis of estrogen control of cell functions. To this end, affinity purification was applied to map and characterize the ERalpha interactome in hormone-responsive human breast cancer cell nuclei. MCF-7 cell clones expressing human ERalpha fused to a tandem affinity purification tag were generated and used to purify native nuclear ER-containing complexes by IgG-Sepharose affinity chromatography and glycerol gradient centrifugation. Purified complexes were analyzed by two-dimensional DIGE and mass spectrometry, leading to the identification of a ligand-dependent multiprotein complex comprising beta-actin, myosins, and several proteins involved in actin filament organization and dynamics and/or known to participate in actin-mediated regulation of gene transcription, chromatin dynamics, and ribosome biogenesis. Time course analyses indicated that complexes containing ERalpha and actin are assembled in the nucleus early after receptor activation by ligands, and gene knockdown experiments showed that gelsolin and the nuclear isoform of myosin 1c are key determinants for assembly and/or stability of these complexes. Based on these results, we propose that the actin network plays a role in nuclear ERalpha actions in breast cancer cells, including coordinated regulation of target gene

  16. Synthesis and evaluation of 17alpha-20E-21-(4-substituted phenyl)-19-norpregna-1,3,5(10),20-tetraene-3,17beta-diols as probes for the estrogen receptor alpha hormone binding domain.

    Science.gov (United States)

    Hanson, Robert N; Lee, Choon Young; Friel, Carolyn J; Dilis, Robert; Hughes, Alun; DeSombre, Eugene R

    2003-07-03

    As part of our program to develop probes for the hormone binding domain of the estrogen receptor alpha (ERalpha), we prepared a series of 4-para-substituted phenylvinyl estradiol derivatives using a combination of solution and solid-phase Pd(0)-catalyzed methods. The compounds 5a-j were evaluated for their binding affinity using the ERalpha hormone binding domain (HDB) isolated from transfected BL21 cells. The results indicated that although the new compounds were somewhat lower in relative binding affinity (RBA at 25 degrees C is 1-60%) than estradiol (100%), most had higher affinity than the unsubstituted parent phenylvinyl estradiol (RBA = 9%). Because the substituents did not generate a structure-activity relationship directly based on physicochemical properties, the series was evaluated using molecular modeling and molecular dynamics to determine key interactions between the ligand, especially the para substituent, and the protein. The results suggest that the observed relative binding affinities are directly related to the calculated binding energies and that amino acids juxtaposed to the para position play a significant but not dominant role in binding. In conclusion, we have identified the 17alpha-E-(4-substituted phenyl)vinyl estradiols as a class of ligands that retain significant affinity for the ERalpha-HBD. In particular, 4-substitution tends to increase receptor affinity compared to the unsubstituted analogue, as exemplified by 5e (4-COCH(3)), which had the highest RBA value (60%) of the series. Palladium(0)-catalyzed coupling reactions on solid support or in solution using suitably substituted iodo arenes and 17alpha-E-tributylstannylvinyl estradiols offer a flexible approach to their preparation. Molecular modeling studies of the receptor suggest that there exists additional ligand accessible regions within the ERalpha-HBD to generate interactions that may enhance receptor affinity or modify efficacy in developing new therapeutic agents. Studies to

  17. The dominant negative thyroid hormone receptor beta-mutant delta337T alters PPAR-alpha signaling in heart

    Science.gov (United States)

    PPARalpha and TR independently regulate cardiac metabolism. Although ligands for both these receptors are currently under evaluation for treatment of congestive heart failure, their interactions or signaling cooperation have not been investigated in heart. We tested the hypothesis that cardiac TRs i...

  18. Effect of estrogen receptor-alpha (ESR1 gene polymorphism on high density lipoprotein levels in response to hormone replacement therapy

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    N.C. Nogueira-de-Souza

    2009-12-01

    Full Text Available Studies have shown that estrogen replacement therapy and estrogen plus progestin replacement therapy alter serum levels of total, LDL and HDL cholesterol levels. However, HDL cholesterol levels in women vary considerably in response to hormone replacement therapy (HRT. A significant portion of the variability of these levels has been attributed to genetic factors. Therefore, we investigated the influence of estrogen receptor-alpha (ESR1 gene polymorphisms on HDL levels in response to postmenopausal HRT. We performed a prospective cohort study on 54 postmenopausal women who had not used HRT before the study and had no significant general medical illness. HRT consisted of conjugated equine estrogen and medroxyprogesterone acetate continuously for 1 year. The lipoprotein levels were measured from blood samples taken before the start of therapy and after 1 year of HRT. ESR1 polymorphism (MspI C>T, HaeIII C>T, PvuII C>T, and XbaI A>G frequencies were assayed by restriction fragment length polymorphism. A general linear model was used to describe the relationships between HDL levels and genotypes after adjusting for age. A significant increase in HDL levels was observed after HRT (P = 0.029. Women with the ESR1 PvuII TT genotype showed a statistically significant increase in HDL levels after HRT (P = 0.032. No association was found between other ESR1 polymorphisms and HDL levels. According to our results, the ESR1 PvuII TT genotype was associated with increased levels of HDL after 1 year of HRT.

  19. The functional relationship between co-repressor N-CoR and SMRT in mediating transcriptional repression by thyroid hormone receptor alpha.

    Science.gov (United States)

    Choi, Kyung-Chul; Oh, So-Young; Kang, Hee-Bum; Lee, Yoo-Hyun; Haam, Seungjoo; Kim, Ha-Il; Kim, Kunhong; Ahn, Young-Ho; Kim, Kyung-Sup; Yoon, Ho-Geun

    2008-04-01

    A central issue in mediating repression by nuclear hormone receptors is the distinct or redundant function between co-repressors N-CoR (nuclear receptor co-repressor) and SMRT (silencing mediator of retinoid and thyroid hormone receptor). To address the functional relationship between SMRT and N-CoR in TR (thyroid hormone receptor)-mediated repression, we have identified multiple TR target genes, including BCL3 (B-cell lymphoma 3-encoded protein), Spot14 (thyroid hormone-inducible hepatic protein), FAS (fatty acid synthase), and ADRB2 (beta-adrenergic receptor 2). We demonstrated that siRNA (small interfering RNA) treatment against either N-CoR or SMRT is sufficient for the de-repression of multiple TR target genes. By the combination of sequence mining and physical association as determined by ChIP (chromatin immunoprecipitation) assays, we mapped the putative TREs (thyroid hormone response elements) in BCL3, Spot14, FAS and ADRB2 genes. Our data clearly show that SMRT and N-CoR are independently recruited to various TR target genes. We also present evidence that overexpression of N-CoR can restore repression of endogenous genes after knocking down SMRT. Finally, unliganded, co-repressor-free TR is defective in repression and interacts with a co-activator, p300. Collectively, these results suggest that both SMRT and N-CoR are limited in cells and that knocking down either of them results in co-repressor-free TR and consequently de-repression of TR target genes.

  20. Mapping of the gene encoding the melanocortin-1 ([alpha]-melanocyte stimulating hormone) receptor (MC1R) to human chromosome 16q24. 3 by fluorescence in situ hybridization

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    Gantz, I.; Yamada, Tadataka; Tashiro, Takao; Konda, Yoshitaka; Shimoto, Yoshimasa; Miwa, Hiroto; Trent, J.M. (Univ. of Michigan Medical Center, Ann Arbor, MI (United States))

    1994-01-15

    [alpha]-Melanocyte stimulating hormone ([alpha]-MSH), a hormone originally named for its ability to regulate pigmentation of melanocytes, is a 13-amino-acid post-translational product of the pro-opiomelanocortin (POMC) gene. [alpha]-MSH and the other products of POMC processing, which share the core heptapeptide amino acid sequence Met-Glu (Gly)-His-Phe-Arg-Trp-Gly (Asp), the adrenocorticotropic hormone (ACTH), [beta]-MSH, and [gamma]-MSH, are collectively referred to as melanocortins. While best known for their effects on the melanocyte (pigmentation) and adrenal cortical cells (steroidogenesis), melanocortins have been postulated to function in diverse activities, including enhancement of learning and memory, control of the cardiovascular system, analgesia, thermoregulation, immunomodulation, parturition, and neurotrophism. To identify the chromosomal band encoding the human melanocortin-1 receptor gene, 1 [mu]g of an EMBL clone coding region of the human MC1R and approximately 15 kb of surrounding DNA was labeled with biotin and hybridized to human metaphase chromosomes as previously described. The results indicate that the human MC1R gene is localized to 16q24.3. 15 refs., 1 fig.

  1. Cloning of partial putative gonadotropin hormone receptor ...

    Indian Academy of Sciences (India)

    Keywords. Glycoprotein hormone receptor; gonadotropin receptor; Labeo rohita; luteinizing hormone receptor; mariner transposon; PCR cloning. Abstract. A search for the presence of mariner-like elements in the Labeo rohita genome by polymerase chain reaction led to the amplification of a partial DNA sequence coding ...

  2. Circulating sex hormones and gene expression of subcutaneous adipose tissue oestrogen and alpha-adrenergic receptors in HIV-lipodystrophy: implications for fat distribution

    DEFF Research Database (Denmark)

    Andersen, Ove; Pedersen, Steen B; Svenstrup, Birgit

    2007-01-01

    OBJECTIVE: Circulating oestradiol and testosterone, which have been shown to increase in human immunodeficiency virus (HIV)-infected patients following highly active antiretroviral therapy (HAART), may influence fat distribution and insulin sensitivity. Oestradiol increases subcutaneous adipose...... determined in 31 nondiabetic HIV-infected male patients receiving HAART (16 with lipodystrophy), in whom measures of fat distribution (CT and DEXA-scans) and insulin sensitivity (hyperinsulinaemic euglycaemic clamp) were available. RESULTS: Total and free oestradiol and testosterone were decreased...... patients, correlated positively with both plasma oestradiol and testosterone (n = 31). Glycerol concentration during clamp (a marker of lipolysis) correlated inversely with expression of alpha2A-adrenergic-receptor, ratio of subcutaneous to total abdominal fat mass, and limb fat, respectively. Expression...

  3. Circulating sex hormones and gene expression of subcutaneous adipose tissue oestrogen and alpha-adrenergic receptors in HIV-lipodystrophy: implications for fat distribution

    DEFF Research Database (Denmark)

    Andersen, Ove; Pedersen, Steen B; Svenstrup, Birgit

    2007-01-01

    determined in 31 nondiabetic HIV-infected male patients receiving HAART (16 with lipodystrophy), in whom measures of fat distribution (CT and DEXA-scans) and insulin sensitivity (hyperinsulinaemic euglycaemic clamp) were available. RESULTS: Total and free oestradiol and testosterone were decreased......OBJECTIVE: Circulating oestradiol and testosterone, which have been shown to increase in human immunodeficiency virus (HIV)-infected patients following highly active antiretroviral therapy (HAART), may influence fat distribution and insulin sensitivity. Oestradiol increases subcutaneous adipose...... patients, correlated positively with both plasma oestradiol and testosterone (n = 31). Glycerol concentration during clamp (a marker of lipolysis) correlated inversely with expression of alpha2A-adrenergic-receptor, ratio of subcutaneous to total abdominal fat mass, and limb fat, respectively. Expression...

  4. Genomic growth hormone, growth hormone receptor and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-20

    Lei et al., 2007). Recently, the effects of bovine growth hormone gene polymorphism at codon 127 and 172 were determined on carcass traits and fatty acid compositions in Japanese Black cattle using allele specific-multiplex ...

  5. Structural Basis for Antibody Discrimination between Two Hormones That Recognize the Parathyroid Hormone Receptor

    Energy Technology Data Exchange (ETDEWEB)

    McKinstry, William J.; Polekhina, Galina; Diefenbach-Jagger, Hannelore; Ho, Patricia W.M.; Sato, Koh; Onuma, Etsuro; Gillespie, Matthew T.; Martin, T. John; Parker, Michael W.; (SVIMR-A); (Chugai); (Melbourne)

    2009-08-18

    Parathyroid hormone-related protein (PTHrP) plays a vital role in the embryonic development of the skeleton and other tissues. When it is produced in excess by cancers it can cause hypercalcemia, and its local production by breast cancer cells has been implicated in the pathogenesis of bone metastasis formation in that disease. Antibodies have been developed that neutralize the action of PTHrP through its receptor, parathyroid hormone receptor 1, without influencing parathyroid hormone action through the same receptor. Such neutralizing antibodies against PTHrP are therapeutically effective in animal models of the humoral hypercalcemia of malignancy and of bone metastasis formation. We have determined the crystal structure of the complex between PTHrP (residues 1-108) and a neutralizing monoclonal anti-PTHrP antibody that reveals the only point of contact is an {alpha}-helical structure extending from residues 14-29. Another striking feature is that the same residues that interact with the antibody also interact with parathyroid hormone receptor 1, showing that the antibody and the receptor binding site on the hormone closely overlap. The structure explains how the antibody discriminates between the two hormones and provides information that could be used in the development of novel agonists and antagonists of their common receptor.

  6. Zearalenone and alpha-zearalenol inhibit the synthesis and secretion of pig follicle stimulating hormone via the non-classical estrogen membrane receptor GPR30.

    Science.gov (United States)

    He, Jing; Wei, Chao; Li, Yueqin; Liu, Ying; Wang, Yue; Pan, Jirong; Liu, Jiali; Wu, Yingjie; Cui, Sheng

    2018-02-05

    Zearalenone (ZEA) is one of the most popular endocrine-disrupting chemicals and is mainly produced by fungi of the genus Fusarium. The excessive intake of ZEA severely disrupts human and animal fertility by affecting the reproductive axis. However, most studies on the effects of ZEA and its metabolite α-zearalenol (α-ZOL) on reproductive systems have focused on gonads. Few studies have investigated the endocrine-disrupting effects of ZEA and α-ZOL on pituitary gonadotropins, including follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The present study was designed to investigate the effects of ZEA and α-ZOL on the synthesis and secretion of FSH and LH and related mechanisms in female pig pituitary. Our in vivo and in vitro results demonstrated that ZEA significantly inhibited the synthesis and secretion of FSH in the pig pituitary gland, but ZEA and α-ZOL had no effects on LH. Our study also showed that ZEA and α-ZOL decreased FSH synthesis and secretion through non-classical estrogen membrane receptor GPR30, which subsequently induced protein kinase cascades and the phosphorylation of PKC, ERK and p38MAPK signaling pathways in pig pituitary cells. Furthermore, our study showed that the LIM homeodomain transcription factor LHX3 was involved in the mechanisms of ZEA and α-ZOL actions on gonadotropes in the female pig pituitary. These findings elucidate the mechanisms behind the physiological alterations resulting from endocrine-disrupting chemicals and further show that the proposed key molecules of the α-ZOL signaling pathway could be potential pharmacological targets. Copyright © 2017. Published by Elsevier B.V.

  7. Ovine prolactin and human growth hormone derivatives. Specific modification of their alpha-amino groups.

    Science.gov (United States)

    Caridad, J J; Nowicki, C; Santomé, J A; Wolfenstein-Todel, C

    1988-06-01

    The alpha-amino group of ovine prolactin (oPRL) and human growth hormone (hGH) was selectively modified by transamination with glyoxylic acid. No difference was found in the binding capacity of transaminated oPRL to rat liver lactogenic receptors with respect to its control, although both samples showed a decrease in its binding capacity with reference to the native hormone. This decrease was due to conformational changes caused by the reaction conditions and not by the transamination itself, as shown by the circular dichroism spectra. Transaminated hGH retained the full binding capacity of the hormone. These results suggest that the alpha-amino group is not relevant for the binding to lactogenic liver receptors in both lactogenic hormones.

  8. alpha-Melanocyte-stimulating-hormone precursors in the pig pituitary

    DEFF Research Database (Denmark)

    Fenger, M

    1986-01-01

    The occurrence of intermediates from the processing of ACTH-(1-39) [adrenocorticotropic hormone-(1-39)] to alpha-melanocyte-stimulating hormone was investigated in normal pig pituitaries by the use of sensitive and specific radioimmunoassays for ACTH-(1-13), ACTH-(1-14), ACTH-(1-13)-NH2 and ACTH-(1...

  9. Sex hormone receptors are present in the human suprachiasmatic nucleus.

    Science.gov (United States)

    Kruijver, Frank P M; Swaab, Dick F

    2002-05-01

    The suprachiasmatic nucleus (SCN) is the clock of the brain that orchestrates circadian and circannual biological rhythms, such as the rhythms of hormones, body temperature, sleep and mood. These rhythms are frequently disturbed in menopause and even more so in dementia and can be restored in postmenopausal women by sex hormone replacement therapy (SHRT). Although it seems clear, both from clinical and experimental studies, that sex hormones influence circadian rhythms, it is not known whether this is by a direct or an indirect effect on the SCN. Therefore, using immunocytochemistry in the present study, we investigated whether the human SCN expresses sex hormone receptors in 5 premenopausal women and 5 young men. SCN neurons appeared to contain estrogen receptor-alpha (ERalpha), estrogen receptor-beta (ERbeta) and progesterone receptors. Median ratings of ER immunoreactivity per individual and per gender group revealed a statistically significantly stronger nuclear ERalpha expression pattern in female SCN neurons (p sexual dimorphic tendency was observed for nuclear ERbeta (p > 0.1) and progesterone receptors (p > 0.7). These data seem to support previously reported functional and structural SCN differences in relation to sex and sexual orientation and indicate for the first time that estrogen and progesterone may act directly on neurons of the human biological clock. In addition, the present findings provide a potential neuroendocrine mechanism by which SHRT can act to improve or restore SCN-related rhythm disturbances, such as body temperature, sleep and mood. Copyright 2002 S. Karger AG, Basel

  10. Pancreatic insulin content regulation by the estrogen receptor ER alpha.

    Directory of Open Access Journals (Sweden)

    Paloma Alonso-Magdalena

    Full Text Available The function of pancreatic beta-cells is the synthesis and release of insulin, the main hormone involved in blood glucose homeostasis. Estrogen receptors, ER alpha and ER beta, are important molecules involved in glucose metabolism, yet their role in pancreatic beta-cell physiology is still greatly unknown. In this report we show that both ER alpha and ER beta are present in pancreatic beta-cells. Long term exposure to physiological concentrations of 17beta-estradiol (E2 increased beta-cell insulin content, insulin gene expression and insulin release, yet pancreatic beta-cell mass was unaltered. The up-regulation of pancreatic beta-cell insulin content was imitated by environmentally relevant doses of the widespread endocrine disruptor Bisphenol-A (BPA. The use of ER alpha and ER beta agonists as well as ER alphaKO and ER betaKO mice suggests that the estrogen receptor involved is ER alpha. The up-regulation of pancreatic insulin content by ER alpha activation involves ERK1/2. These data may be important to explain the actions of E2 and environmental estrogens in endocrine pancreatic function and blood glucose homeostasis.

  11. Molecular Modeling of Estrogen Receptor Alpha Mutated Breast Cancer to Guide New Therapeutic Strategies

    Science.gov (United States)

    2017-10-01

    ER in 10-40% of metastatic hormone therapy resistant breast tumors suggests that these mutations may be a common mechanism leading to resistance...LBD) of ER in approximately 20% of metastatic hormone therapy resistant breast tumors suggests that these mutations are a common mechanism leading...mutations. 2. KEYWORDS Breast cancer, Estrogen receptor alpha, hormone therapy resistance, gene regulation, genomics, CRSIPR/Cas9, epigenetic

  12. Zonal variation in the distribution of an alpha 1-acid glycoprotein glycoform receptor in human adrenal cortex

    DEFF Research Database (Denmark)

    Andersen, U O; Bøg-Hansen, T C; Kirkeby, S

    1999-01-01

    specific receptor. The binding of alpha 1-acid glycoprotein glycoform B and alpha 1-acid glycoprotein glycoform C to the glycoform specific receptor is inhibited by the steroid hormones cortisone, aldosterone, estradiol and progesterone but not by testosterone. The pronounced changes in the distribution...

  13. Ligands specify estrogen receptor alpha nuclear localization and degradation

    OpenAIRE

    Caze-Subra Stéphanie; Mazaheri Mahta; Kocanova Silvia; Bystricky Kerstin

    2010-01-01

    Abstract Background The estrogen receptor alpha (ERα) is found predominately in the nucleus, both in hormone stimulated and untreated cells. Intracellular distribution of the ERα changes in the presence of agonists but the impact of different antiestrogens on the fate of ERα is a matter of debate. Results A MCF-7 cell line stably expressing GFP-tagged human ERα (SK19 cell line) was created to examine the localization of ligand-bound GFP-ERα. We combined digitonin-based cell fractionation anal...

  14. Growth hormone receptor gene expression in puberty.

    Science.gov (United States)

    Pagani, S; Meazza, C; Gertosio, C; Bozzola, E; Bozzola, M

    2015-07-01

    The mechanisms regulating the synergic effect of growth hormone and other hormones during pubertal spurt are not completely clarified. We enrolled 64 females of Caucasian origin and normal height including 22 prepubertal girls, 26 pubertal girls, and 16 adults to evaluate the role of Growth Hormone/Insulin-like growth factor-I axis (GH/IGF-I) during the pubertal period. In these subjects both serum IGF-I and growth hormone binding protein levels, as well as quantitative growth hormone receptor (GHR) gene expression were evaluated in peripheral lymphocytes of all individuals by real-time PCR. Our results showed significantly lower IGF-I levels in women (148±10 ng/ml) and prepubertal girls (166.34±18.85 ng/ml) compared to pubertal girls (441.95±29.42 ng/ml; p<0.0001). Serum GHBP levels were significantly higher in prepubertal (127.02±20.76 ng/ml) compared to pubertal girls (16.63±2.97 ng/ml; p=0.0001) and adult women (19.95±6.65 ng/ml; p=0.0003). We also found higher GHR gene expression levels in pubertal girls [174.73±80.22 ag (growth hormone receptor)/5×10(5) ag (glyceraldehyde 3-phosphate dehydrogenase)] compared with other groups of subjects [women: 42.52±7.66 ag (growth hormone receptor)/5×10(5) ag (glyceraldehyde 3-phosphate dehydrogenase); prepubertal girls: 58.45±0.18.12 ag (growth hormone receptor)/5×10(5) ag (glyceraldehyde 3-phosphate dehydrogenase)], but the difference did not reach statistical significance. These results suggest that sexual hormones could positively influence GHR action, during the pubertal period, in a dual mode, that is, increasing GHR mRNA production and reducing GHR cleavage leading to GHBP variations. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Sex hormone receptors in breast cancer.

    Science.gov (United States)

    D'Abreo, Nina; Hindenburg, Alexander A

    2013-01-01

    The dependency of certain breast cancers on estrogen is undeniably one of the most important observations in oncology. Since this early observation, there has been a tremendous effort to define the precise roles of the estrogen receptor (ER) in the pathogenesis of breast cancer. Estrogen signaling pathways can also be exploited as effective targets for cancer treatment. Both ligand-dependent and ligand-independent receptor activation pathways have been successfully blocked by hormonal therapies including selective ER modulators such as tamoxifen, by blocking and accelerating the degradation of ER (fulvestrant), and by depleting tissue levels of estrogen (aromatase inhibitors). Because of the immense prognostic and predictive value of the ER and PR receptor, accurately defining hormone dependency is also of paramount importance. Despite this avalanche of discovery and development resulting in improved outcome for the patient, resistance to these therapies, both intrinsic and acquired, is well known. Uncovering the various mechanisms of resistance has deepened scientific understanding of posttranslational modifications of these receptors, as well as their cross talk with other receptor families such as the HER-2/neu receptor. The recent discovery that orphan estrogen-related receptors may also play an important role in breast cancer is just starting to be appreciated. A clear understanding of the historical perspective and the intricacies of ER structure and function is required to improve current therapeutic strategies for breast cancer. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Growth hormone-releasing hormone resistance in pseudohypoparathyroidism type ia: new evidence for imprinting of the Gs alpha gene.

    Science.gov (United States)

    Mantovani, Giovanna; Maghnie, Mohamad; Weber, Giovanna; De Menis, Ernesto; Brunelli, Valeria; Cappa, Marco; Loli, Paola; Beck-Peccoz, Paolo; Spada, Anna

    2003-09-01

    Heterozygous inactivating mutations in the Gs alpha gene cause Albright's hereditary osteodystrophy. Consistent with the observation that only maternally inherited mutations lead to resistance to hormone action [pseudohypoparathyroidism type Ia (PHP Ia)], recent studies provided evidence for a predominant maternal origin of Gs alpha transcripts in endocrine organs, such as thyroid, gonad, and pituitary. The aim of this study was to investigate the presence of pituitary resistance to hypothalamic hormones acting via Gs alpha-coupled receptors in patients with PHP Ia. Six of nine patients showed an impaired GH responsiveness to GHRH plus arginine, consistent with a complete GH deficiency (GH peak from 2.6-8.6 microg/liter, normal > 16.5), and partial (GH peak 13.9 and 13.6 microg/liter) and normal responses were found in two and one patient, respectively. Accordingly, IGF-I levels were below and in the low-normal range in seven and two patients. All patients had a normal cortisol response to 1 microg ACTH test, suggesting a normal corticotroph function that was confirmed by a normal ACTH and cortisol response to CRH test in three patients. In conclusion, we report that in addition to PTH and TSH resistance, patients with PHP Ia display variable degrees of GHRH resistance, consistent with Gs alpha imprinting in human pituitary.

  17. Prognostic Value of Estrogen Receptor alpha and Progesterone Receptor Conversion in Distant Breast Cancer Metastases

    NARCIS (Netherlands)

    Hoefnagel, Laurien D. C.; Moelans, Cathy B.; Meijer, S. L.; van Slooten, Henk-Jan; Wesseling, Pieter; Wesseling, Jelle; Westenend, Pieter J.; Bart, Joost; Seldenrijk, Cornelis A.; Nagtegaal, Iris D.; Oudejans, Joost; van der Valk, Paul; van Gils, Carla H.; van der Wall, Elsken; van Diest, Paul J.

    2012-01-01

    BACKGROUND: Changes in the receptor profile of primary breast cancers to their metastases (receptor conversion) have been described for the estrogen receptor alpha (ER alpha) and progesterone receptor (PR). The purpose of this study was to evaluate the impact of receptor conversion for ER alpha and

  18. Steroid-Functionalized Titanocenes: Docking Studies with Estrogen Receptor Alpha

    Directory of Open Access Journals (Sweden)

    Li Ming Gao

    2016-11-01

    Full Text Available Estrogen receptor alpha (ERα is a transcription factor that is activated by hormones, with 17β-estradiol being its most active agonist endogenous ligand. ERα is also activated or inactivated by exogenous ligands. ER is overexpressed in hormone-dependent breast cancer, and one of the treatments for this type of cancer is the use of an ER antagonist to halt cell proliferation. We have previously reported four steroid-functionalized titanocenes: pregnenolone, dehydroepiandrosterone (DHEA, trans-androsterone, and androsterone. These steroids have hormonal activity as well as moderate antiproliferative activity, thus these steroids could act as vectors for the titanocene dichloride to target hormone-dependent cancers. Also, these steroids could increase the antiproliferative activity of the resulting titanocenes based on synergism. In order to elucidate which factors contribute to the enhanced antiproliferative activity of these steroid-functionalized titanocenes, we performed docking studies between ERα and the titanocenes and the steroids. The binding affinities and type of bonding interactions of the steroid-functionalized titanocenes with ERα are herein discussed.

  19. Steroid hormone receptor phosphorylation: Is there a physiological role?

    NARCIS (Netherlands)

    G.G.J.M. Kuiper (George); A.O. Brinkmann (Albert)

    1994-01-01

    textabstractAll members of the steroid hormone receptor family are phosphoproteins. Additional phosphorylation occurs in the presence of hormone. This hormone-induced phosphorylation, which is 2- to 7-fold more than the basal phosphorylation, is a rapid process. All steroid receptors are

  20. Molecular recognition of parathyroid hormone by its G protein-coupled receptor

    Energy Technology Data Exchange (ETDEWEB)

    Pioszak, Augen A.; Xu, H. Eric (Van Andel)

    2008-08-07

    Parathyroid hormone (PTH) is central to calcium homeostasis and bone maintenance in vertebrates, and as such it has been used for treating osteoporosis. It acts primarily by binding to its receptor, PTH1R, a member of the class B G protein-coupled receptor (GPCR) family that also includes receptors for glucagon, calcitonin, and other therapeutically important peptide hormones. Despite considerable interest and much research, determining the structure of the receptor-hormone complex has been hindered by difficulties in purifying the receptor and obtaining diffraction-quality crystals. Here, we present a method for expression and purification of the extracellular domain (ECD) of human PTH1R engineered as a maltose-binding protein (MBP) fusion that readily crystallizes. The 1.95-{angstrom} structure of PTH bound to the MBP-PTH1R-ECD fusion reveals that PTH docks as an amphipathic helix into a central hydrophobic groove formed by a three-layer {alpha}-{beta}-{beta}{alpha} fold of the PTH1R ECD, resembling a hot dog in a bun. Conservation in the ECD scaffold and the helical structure of peptide hormones emphasizes this hot dog model as a general mechanism of hormone recognition common to class B GPCRs. Our findings reveal critical insights into PTH actions and provide a rational template for drug design that targets this hormone signaling pathway.

  1. Association between steroid hormone receptors and PSA gene ...

    African Journals Online (AJOL)

    associated with presence of steroid hormone receptors. The aim of this research was to show differential expression and association between steroid hormone receptors and PSA gene expression in breast cancer cell lines. The cell lines investigated were steroid receptor-negative breast carcinoma cell lines BT-20 and ...

  2. alpha-Melanocyte-stimulating-hormone precursors in the pig pituitary

    DEFF Research Database (Denmark)

    Fenger, M

    1986-01-01

    The occurrence of intermediates from the processing of ACTH-(1-39) [adrenocorticotropic hormone-(1-39)] to alpha-melanocyte-stimulating hormone was investigated in normal pig pituitaries by the use of sensitive and specific radioimmunoassays for ACTH-(1-13), ACTH-(1-14), ACTH-(1-13)-NH2 and ACTH-(1......-39). Fractionation by reverse-phase h.p.l.c. revealed ACTH(1-17) and their acetylated analogues. The intermediate lobe contained NO-diacetyl-ACTH-(1-13)-NH2, N-acetyl-ACTH-(1-13)-NH2 and ACTH-(1-13)-NH2. In addition, the corresponding ACTH-(1-14) peptides (the glycine-extended precursor of the amidated peptides...

  3. Estrogen receptor alpha: molecular mechanisms and emerging insights.

    Science.gov (United States)

    Candelaria, Nicholes R; Liu, Ka; Lin, Chin-Yo

    2013-10-01

    Estrogen receptor alpha (ERα) is a cellular receptor for the female sex hormone estrogen and other natural and synthetic ligands and play critical roles in normal development and physiology and in the etiology and treatment of endocrine-related diseases. ERα is a member of the nuclear receptor superfamily of transcription factors and regulates target gene expression in a ligand-dependent manner. It has also been shown to interact with G-protein coupled receptors and associated signaling molecules in the cytoplasm. Transcriptionally, ERα either binds DNA directly through conserved estrogen response element sequence motifs or indirectly by tethering to other interacting transcription factors and nucleate transcriptional regulatory complexes which include an array of co-regulator proteins. Genome-scale studies of ERα transcriptional activity and localization have revealed mechanistic complexity and insights including novel interactions with several transcription factors, including FOXA1, AP-2g, GATA3, and RUNX1, which function as pioneering, collaborative, or tethering factors. The major challenge and exciting prospect moving forward is the comprehensive definition and integration of ERα complexes and mechanisms and their tissue-specific roles in normal physiology and in human diseases. Copyright © 2013 Wiley Periodicals, Inc.

  4. Effect of mutations in the beta1-thyroid hormone receptor on the inhibition of T3 binding by desethylamiodarone

    NARCIS (Netherlands)

    van Beeren, H. C.; Bakker, O.; Chatterjee, V. K.; Wiersinga, W. M.

    1999-01-01

    Desethylamiodarone (DEA) acts as a competitive inhibitor of triiodothyronine (T3) binding to the alpha1-thyroid hormone receptor (TR alpha1) but as a non-competitive inhibitor with respect to TR beta1. To gain insight into the position of the binding site of desethylamiodarone on TR beta1 we

  5. Endocrine therapy use among elderly hormone receptor-pos...

    Data.gov (United States)

    U.S. Department of Health & Human Services — Clinical guidelines recommend that women with hormone-receptor positive breast cancer receive endocrine therapy (selective estrogen receptor modulators or aromatase...

  6. Thyroid-stimulating hormone receptor and thyroid hormone receptors are involved in human endometrial physiology.

    Science.gov (United States)

    Aghajanova, Lusine; Stavreus-Evers, Anneli; Lindeberg, Maria; Landgren, Britt-Marie; Sparre, Lottie Skjöldebrand; Hovatta, Outi

    2011-01-01

    To study the expression, distribution, and function of thyroid-stimulating hormone receptor (TSHR) and thyroid hormone receptors (TR) α1, α2, and β1 in human endometrium. Experimental clinical study. University hospital. 31 fertile women. Endometrial biopsy samples obtained throughout the menstrual cycle. Real-time reverse transcriptase polymerase chain reaction, immunohistochemistry and Western blot to study the expression of TSHR, TRα1, TRα2, and TRβ1 messenger RNA (mRNA) and proteins in human endometrium. We found TSHR, TRα1, TRα2 and TRβ1 mRNA and proteins expressed in human endometrium. Immunostaining for TSHR in the luminal epithelium and TRα1 and β1 in the glandular and luminal epithelium increased statistically significantly on luteinizing hormone (LH) days 6 to 9, coinciding with appearance of pinopodes. Endometrial stromal and Ishikawa cells expressed mRNA for TSHR, TR, and iodothyronine deiodinases 1-3. After 48 hours, TSH significantly increased leukemia inhibitory factor (LIF) and LIF receptor (LIFR) messenger RNA (mRNA) in endometrial stromal cells, but decreased their expression in Ishikawa cells. Glucose transporter 1 mRNA was up-regulated by TSH in Ishikawa cells. We found that TSH statistically significantly increased secretion of free triiodothyronine (T3) and total thyroxin (T4) by Ishikawa cells compared with nonstimulated cells. Thyroid hormones are directly involved in endometrial physiology. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  7. Steroid Hormone Receptor Signals as Prognosticators for Urothelial Tumor

    Directory of Open Access Journals (Sweden)

    Hiroki Ide

    2015-01-01

    Full Text Available There is a substantial amount of preclinical or clinical evidence suggesting that steroid hormone receptor-mediated signals play a critical role in urothelial tumorigenesis and tumor progression. These receptors include androgen receptor, estrogen receptors, glucocorticoid receptor, progesterone receptor, vitamin D receptor, retinoid receptors, peroxisome proliferator-activated receptors, and others including orphan receptors. In particular, studies using urothelial cancer tissue specimens have demonstrated that elevated or reduced expression of these receptors as well as alterations of their upstream or downstream pathways correlates with patient outcomes. This review summarizes and discusses available data suggesting that steroid hormone receptors and related signals serve as biomarkers for urothelial carcinoma and are able to predict tumor recurrence or progression.

  8. Evidence for Alpha Receptors in the Human Ureter

    Science.gov (United States)

    Madeb, Ralph; Knopf, Joy; Golijanin, Dragan; Bourne, Patricia; Erturk, Erdal

    2007-04-01

    An immunohistochemical and western blot expression analysis of human ureters was performed in order to characterize the alpha-1-adrenergic receptor distribution along the length of the human ureteral wall. Mapping the distribution will assist in understanding the potential role alpha -1-adrenergic receptors and their subtype density might have in the pathophysiology of ureteral colic and stone passage. Patients diagnosed with renal cancer or bladder cancer undergoing nephrectomy, nephroureterectomy, or cystectomy had ureteral specimens taken from the proximal, mid, distal and tunneled ureter. Tissues were processed for fresh frozen examination and fixed in formalin. None of the ureteral specimens were involved with cancer. Serial histologic sections and immunohistochemical studies were performed using antibodies specific for alpha-1-adrenergic receptor subtypes (alpha 1a, alpha 1b, alpha 1d). The sections were examined under a light microscope and scored as positive or negative. In order to validate and quantify the alpha receptor subtypes along the human ureter. Western blotting techniques were applied. Human ureter stained positively for alpha -1-adrenergic receptors. Immunostaining appeared red, with intense reaction in the smooth muscle of the ureter and endothelium of the neighboring blood vessels. There was differential expression between all the receptors with the highest staining for alpha-1D subtype. The highest protein expression for all three subtypes was in the renal pelvis and decreased with advancement along the ureter to the distal ureter. At the distal ureter, there was marked increase in expression as one progressed towards the ureteral orifice. The same pattern of protein expression was exhibited for all three alpha -1-adrenergic receptor subtypes. We provide preliminary evidence for the ability to detect and quantify the alpha-1-receptor subtypes along the human ureter which to the best of our knowledge has never been done with

  9. Metastatic Breast Cancer and Hormonal Receptor Status among a ...

    African Journals Online (AJOL)

    hormone receptor status correlates with site of metastatic lesions and survival among breast cancer patients. Objective: To determine the sites of metastatic breast lesions and how they relate to the hormonal receptor status. Methods: In this cross sectional descriptive study, 71 women with histologically confirmed incident ...

  10. Hormone receptor expression in male breast cancers | Akosa ...

    African Journals Online (AJOL)

    Male breast cancers are rare but have been found in higher proportions in Black Africans. Prognostic factors for breast cancers include tumour size, grade and stage, and hormone receptor status. The hormone receptor status is an invaluable guide in the use of adjuvant endocrine therapy, but none of the reports available ...

  11. Importance of hormone receptors in breast cancer

    Directory of Open Access Journals (Sweden)

    Nohelia Muñoz-Ordóñez

    2013-09-01

    Full Text Available The basis of the diagnosis of breast cancer is the histological confirmation of it. In the diagnostic methods performed on biopsy specimens and / or surgical specimens of patients, analysis of hormone receptors, provides information to the appropriate prescription of the endocrine treatments used today, in addition to having utility as a prognostic factor in determining the risk of recurrence post treatment and evaluate the response. To obtain tumor tissue, also allows to determine prognostic and predictive factors such as histopathological classification of the tumor, its size, number of positive lymph nodes and lymph-vascular commitment, all of them very important in a integrated treatment, in order to improve the quality and life expectancy of patients.

  12. Helix 3-Helix 5 interactions in Steroid Hormone Receptor Function

    Science.gov (United States)

    Zhang, Junhui; Geller, David S.

    2009-01-01

    Steroid hormones working through their receptors regulate a wide variety of physiologic processes necessary for normal homeostasis. Recent years have witnessed great advances in our understanding of how these hormones interact with their receptors, and have brought us closer to the era of directed drug design. We previously described a novel intramolecular interaction between helix 3 and helix 5 which is responsible for a Mendelian form of human hypertension. Further studies revealed that this interaction is highly conserved throughout the steroid hormone receptor family and functions as a key regulator of steroid hormone receptor sensitivity and specificity. Here, we review the contribution of helix 3-helix 5 interaction to steroid hormone receptor activity, with an eye towards how this knowledge may aid in the creation of novel therapeutic agonists and antagonists. PMID:18502379

  13. Thyroid Hormone Receptor beta Mediates Acute Illness-Induced Alterations in Central Thyroid Hormone Metabolism

    NARCIS (Netherlands)

    Boelen, Anita; Kwakkel, Joan; Chassande, Olivier; Fliers, Eric

    2009-01-01

    Acute illness in mice profoundly affects thyroid hormone metabolism in the hypothalamus and pituitary gland. It remains unknown whether the thyroid hormone receptor (TR)-beta is involved in these changes. In the present study, we investigated central thyroid hormone metabolism during

  14. Thyroid hormone receptors in health and disease

    NARCIS (Netherlands)

    Boelen, A.; Kwakkel, J.; Fliers, E.

    2012-01-01

    Thyroid hormones (TH) play a key role in energy homeostasis throughout life. Thyroid hormone production and secretion by the thyroid gland is regulated via the hypothalamus-pituitary-thyroid (HPT)-axis. Thyroid hormone has to be transported into the cell, where it can bind to the thyroid hormone

  15. Autoinduction of thyroid hormone receptor during metamorphosis is reproduced in Xenopus XTC-2 cells.

    Science.gov (United States)

    Machuca, I; Tata, J R

    1992-09-01

    To determine if the autoinduction of thyroid hormone receptor (TR) alpha and beta mRNAs during metamorphosis in Xenopus tadpoles can be reproduced in cultured cells, we have screened four Xenopus cell lines (XTC-2, XL-177, XL2 and Kr) for receptor transcripts and their response to thyroid hormone. Exposure of XTC-2 cells to 10(-9) M triiodothyronine (T3) for 24 h upregulated TR alpha and beta mRNAs by 2-4- and 10-40-fold, respectively. In view of the marked similarity of the differential distribution of the two transcripts and their upregulation by T3 to the pattern of autoinduction seen in whole tadpoles, the process was studied in greater detail in XTC-2 cells. The time-course of autoinduction of TR alpha and beta mRNAs in these cells also resembled that in vivo, the two transcripts being significantly induced by 3-6 h after T3. Dose-response to T3, and the relative responses to its active and inactive analogs, confirmed that the process of autoinduction was initiated by thyroid hormone receptor with the same functional characteristics as that found in all amphibian and mammalian tissues. Experiments performed with cycloheximide suggested that intermediary protein(s) were involved in autoinduction, so that TR genes cannot be considered as 'immediate early' genes for this process. The possible advantages of studying thyroid hormone action in metamorphosis in XTC-2 cells are briefly discussed.

  16. Hmrbase: a database of hormones and their receptors

    Directory of Open Access Journals (Sweden)

    Kumar Manish

    2009-07-01

    Full Text Available Abstract Background Hormones are signaling molecules that play vital roles in various life processes, like growth and differentiation, physiology, and reproduction. These molecules are mostly secreted by endocrine glands, and transported to target organs through the bloodstream. Deficient, or excessive, levels of hormones are associated with several diseases such as cancer, osteoporosis, diabetes etc. Thus, it is important to collect and compile information about hormones and their receptors. Description This manuscript describes a database called Hmrbase which has been developed for managing information about hormones and their receptors. It is a highly curated database for which information has been collected from the literature and the public databases. The current version of Hmrbase contains comprehensive information about ~2000 hormones, e.g., about their function, source organism, receptors, mature sequences, structures etc. Hmrbase also contains information about ~3000 hormone receptors, in terms of amino acid sequences, subcellular localizations, ligands, and post-translational modifications etc. One of the major features of this database is that it provides data about ~4100 hormone-receptor pairs. A number of online tools have been integrated into the database, to provide the facilities like keyword search, structure-based search, mapping of a given peptide(s on the hormone/receptor sequence, sequence similarity search. This database also provides a number of external links to other resources/databases in order to help in the retrieving of further related information. Conclusion Owing to the high impact of endocrine research in the biomedical sciences, the Hmrbase could become a leading data portal for researchers. The salient features of Hmrbase are hormone-receptor pair-related information, mapping of peptide stretches on the protein sequences of hormones and receptors, Pfam domain annotations, categorical browsing options, online

  17. Hmrbase: a database of hormones and their receptors

    Science.gov (United States)

    Rashid, Mamoon; Singla, Deepak; Sharma, Arun; Kumar, Manish; Raghava, Gajendra PS

    2009-01-01

    Background Hormones are signaling molecules that play vital roles in various life processes, like growth and differentiation, physiology, and reproduction. These molecules are mostly secreted by endocrine glands, and transported to target organs through the bloodstream. Deficient, or excessive, levels of hormones are associated with several diseases such as cancer, osteoporosis, diabetes etc. Thus, it is important to collect and compile information about hormones and their receptors. Description This manuscript describes a database called Hmrbase which has been developed for managing information about hormones and their receptors. It is a highly curated database for which information has been collected from the literature and the public databases. The current version of Hmrbase contains comprehensive information about ~2000 hormones, e.g., about their function, source organism, receptors, mature sequences, structures etc. Hmrbase also contains information about ~3000 hormone receptors, in terms of amino acid sequences, subcellular localizations, ligands, and post-translational modifications etc. One of the major features of this database is that it provides data about ~4100 hormone-receptor pairs. A number of online tools have been integrated into the database, to provide the facilities like keyword search, structure-based search, mapping of a given peptide(s) on the hormone/receptor sequence, sequence similarity search. This database also provides a number of external links to other resources/databases in order to help in the retrieving of further related information. Conclusion Owing to the high impact of endocrine research in the biomedical sciences, the Hmrbase could become a leading data portal for researchers. The salient features of Hmrbase are hormone-receptor pair-related information, mapping of peptide stretches on the protein sequences of hormones and receptors, Pfam domain annotations, categorical browsing options, online data submission, Drug

  18. Estrogen and Progesterone hormone receptor expression in oral cavity cancer.

    Science.gov (United States)

    Grimm, M; Biegner, T; Teriete, P; Hoefert, S; Krimmel, M; Munz, A; Reinert, S

    2016-09-01

    Recent studies have shown an increase in the incidence of oral squamous cell carcinoma (OSCC) in younger patients. The hypothesis that tumors could be hormonally induced during pregnancy or in young female patients without the well-known risk factors alcohol or tobacco abuse seems to be plausible. Estrogen Receptor alpha (ERα) and Progesterone Receptor (PR) expression were analyzed in normal oral mucosa (n=5), oral precursor lesions (simple hyperplasia, n=11; squamous intraepithelial neoplasia, SIN I-III, n=35), and OSCC specimen. OSCCs were stratified in a young female (n=7) study cohort and older patients (n=46). In the young female study cohort three patients (n=3/7) developed OSCC during or shortly after pregnancy. Breast cancer tissues were used as positive control for ERα and PR expression. ERα expression was found in four oral precursor lesions (squamous intraepithelial neoplasia, SIN I-III, n=4/35, 11%) and in five OSCC specimen (n=5/46, 11%). The five ERα positive OSCC samples were older male patients. All patients within the young female study cohort were negatively stained for both ERα and PR. ER expression could be regarded as a seldom risk factor for OSCC. PR expression seems to be not relevant for the development of OSCC.

  19. The reciprocal regulation of stress hormones and GABAA receptors

    Directory of Open Access Journals (Sweden)

    Istvan eMody

    2012-01-01

    Full Text Available Stress-derived steroid hormones regulate the expression and function of GABAA receptors (GABAARs. Changes in GABAAR subunit expression have been demonstrated under conditions of altered steroid hormone levels, such as stress, as well as following exogenous steroid hormone administration. In addition to the effects of stress-derived steroid hormones on GABAAR subunit expression, stress hormones can also be metabolized to neuroactive derivatives which can alter the function of GABAARs. Neurosteroids allosterically modulate GABAARs at concentrations comparable to those during stress. In addition to the actions of stress-derived steroid hormones on GABAARs, GABAARs reciprocally regulate the production of stress hormones. The stress response is mediated by the hypothalamic-pituitary-adrenal (HPA axis, the activity of which is governed by corticotropin releasing hormone (CRH neurons. The activity of CRH neurons is largely controlled by robust GABAergic inhibition. Recently, it has been demonstrated that CRH neurons are regulated by neurosteroid-sensitive, GABAAR δ subunit-containing receptors representing a novel feedback mechanism onto the HPA axis. Further, it has been demonstrated that neurosteroidogenesis and neurosteroid actions on GABAAR δ subunit-containing receptors on CRH neurons are necessary to mount the physiological response to stress. Here we review the literature describing the effects of steroid hormones on GABAARs as well as the importance of GABAARs in regulating the production of steroid hormones. This review incorporates what we currently know about changes in GABAARs following stress and the role in HPA axis regulation.

  20. Alpha 2-adrenergic receptor turnover in adipose tissue and kidney: irreversible blockade of alpha 2-adrenergic receptors by benextramine

    Energy Technology Data Exchange (ETDEWEB)

    Taouis, M.; Berlan, M.; Lafontan, M.

    1987-01-01

    The recovery of post- and extrasynaptic alpha 2-adrenergic receptor-binding sites was studied in vivo in male golden hamsters after treatment with an irreversible alpha-adrenoceptor antagonist benextramine, a tetramine disulfide that possesses a high affinity for alpha 2-binding sites. The kidney alpha 2-adrenergic receptor number was measured with (/sup 3/H)yohimbine, whereas (/sup 3/H)clonidine was used for fat cell and brain membrane alpha 2-binding site identification. Benextramine treatment of fat cell, kidney, and brain membranes reduced or completely suppressed, in an irreversible manner, (/sup 3/H) clonidine and (/sup 3/H)yohimbine binding without modifying adenosine (A1-receptor) and beta-adrenergic receptor sites. This irreversible binding was also found 1 and 2 hr after intraperitoneal administration of benextramine to the hamsters. Although it bound irreversibly to peripheral and central alpha 2-adrenergic receptors on isolated membranes, benextramine was unable to cross the blood-brain barrier of the hamster at the concentrations used (10-20 mg/kg). After the irreversible blockade, alpha 2-binding sites reappeared in kidney and adipose tissue following a monoexponential time course. Recovery of binding sites was more rapid in kidney than in adipose tissue; the half-lives of the receptor were 31 and 46 hr, respectively in the tissues. The rates of receptor production were 1.5 and 1.8 fmol/mg of protein/hr in kidney and adipose tissue. Reappearance of alpha 2-binding sites was associated with a rapid recovery of function (antilipolytic potencies of alpha 2-agonists) in fat cells inasmuch as occupancy of 15% of (/sup 3/H)clonidine-binding sites was sufficient to promote 40% inhibition of lipolysis. Benextramine is a useful tool to estimate turnover of alpha 2-adrenergic receptors under normal and pathological situations.

  1. GABA(A) receptor alpha4 subunit suppression prevents withdrawal properties of an endogenous steroid.

    Science.gov (United States)

    Smith, S S; Gong, Q H; Hsu, F C; Markowitz, R S; ffrench-Mullen, J M; Li, X

    1998-04-30

    The hormone progesterone is readily converted to 3alpha-OH-5alpha-pregnan-20-one (3alpha,5alpha-THP) in the brains of males and females. In the brain, 3alpha,5alpha-THP acts like a sedative, decreasing anxiety and reducing seizure activity, by enhancing the function of GABA (gamma-aminobutyric acid), the brain's major inhibitory neurotransmitter. Symptoms of premenstrual syndrome (PMS), such as anxiety and seizure susceptibility, are associated with sharp declines in circulating levels of progesterone and, consequently, of levels of 3alpha,5alpha-THP in the brain. Abrupt discontinuation of use of sedatives such as benzodiazepines and ethanol can also produce PMS-like withdrawal symptoms. Here we report a progesterone-withdrawal paradigm, designed to mimic PMS and post-partum syndrome in a rat model. In this model, withdrawal of progesterone leads to increased seizure susceptibility and insensitivity to benzodiazepine sedatives through an effect on gene transcription. Specifically, this effect was due to reduced levels of 3alpha,5alpha-THP which enhance transcription of the gene encoding the alpha4 subunit of the GABA(A) receptor. We also find that increased susceptibility to seizure after progesferone withdrawal is due to a sixfold decrease in the decay time for GABA currents and consequent decreased inhibitory function. Blockade of the alpha4 gene transcript prevents these withdrawal properties. PMS symptoms may therefore be attributable, in part, to alterations in expression of GABA(A) receptor subunits as a result of progesterone withdrawal.

  2. Genome inventory and analysis of nuclear hormone receptors in ...

    Indian Academy of Sciences (India)

    Prakash

    2006-12-20

    , UAS-GKVK Campus, Bellary Road,. Bangalore 560 065 .... have important implications in biology and in understanding the evolutionary and ..... Rechavi M 2004 Update of NUREBASE: nuclear hormone receptor functional ...

  3. Molecular identification of the first insect ecdysis triggering hormone receptors

    DEFF Research Database (Denmark)

    Iversen, Annette; Cazzamali, Giuseppe; Williamson, Michael

    2002-01-01

    be activated by low concentrations of Drosophila ecdysis triggering hormones-1 and -2. Ecdysis (cuticle shedding) is an important behaviour, allowing growth and metamorphosis in insects and other arthropods. Our paper is the first report on the molecular identification of ecdysis triggering hormone receptors...... from insects....

  4. Evaluation of estrogen receptor alpha and beta and progesterone receptor expression and correlation with clinicopathologic factors and proliferative marker Ki-67 in breast cancers

    DEFF Research Database (Denmark)

    Rosa, Fabíola E; Caldeira, José R F; Felipes, Joice

    2008-01-01

    To elucidate the molecular profile of hormonal steroid receptor status, we analyzed ER-alpha, ER-beta, and PGR mRNA and protein expression in 80 breast carcinomas using reverse transcriptase polymerase chain reaction (RT-PCR), quantitative RT-PCR, and immunohistochemical analysis. Qualitative ana...

  5. Palbociclib in Combination With Tamoxifen as First Line Therapy for Metastatic Hormone Receptor Positive Breast Cancer

    Science.gov (United States)

    2017-08-23

    Hormone Receptor Positive Malignant Neoplasm of Breast; Human Epidermal Growth Factor 2 Negative Carcinoma of Breast; Estrogen Receptor Positive Breast Cancer; Progesterone Receptor Positive Tumor; Metastatic Breast Cancer

  6. GABA regulates the rat hypothalamic-pituitary-adrenocortical axis via different GABA-A receptor alpha-subtypes

    DEFF Research Database (Denmark)

    Mikkelsen, Jens D; Bundzikova, Jana; Larsen, Marianne Hald

    2008-01-01

    The control of the corticotropin-releasing hormone (CRH) neurons in the hypothalamic paraventricular nucleus (PVN) is balanced by excitatory and inhibitory inputs. The GABA-A receptor, which is a major target for the inhibitory control, is composed of five subunits. The presence of an alpha(1)-, ...

  7. Status of sex steroid hormone receptors in large bowel cancer

    NARCIS (Netherlands)

    Meggouh, F.; Lointier, P.; Pezet, D.; Saez, S.

    1991-01-01

    To determine the potential role of sex steroid hormones in the development of colorectal tumors in humans, specific androgen (AR), estrogen (ER), and progesterone (PGR) receptors were investigated in normal mucosa (NM) and in tumor (T) paired biopsy specimens from 94 patients. Androgen receptors

  8. Role of TNF-alpha and its receptors in pericoronitis.

    Science.gov (United States)

    Beklen, A; Laine, M; Ventä, I; Hyrkäs, T; Konttinen, Y T

    2005-12-01

    The classic stimulus for cellular cytokine production is bacterial lipopolysaccharide (endotoxin). It was therefore hypothesized that tumor necrosis factor-alpha (TNF-alpha) may be responsible for pericoronitis. TNF-alpha and its receptors were detected by immunohistochemical staining in third molar pericoronitis in ten patients and ten healthy control samples. The percentage of TNF-alpha positive cells was high in pericoronitis (p = 0.0317). TNF receptors TNF-R1 and TNF-R2 were found in macrophage- and fibroblast-like cells, vascular endothelial cells in post-capillary venules, and basal epithelial cells in pericoronitis, but were only weakly expressed in controls. Increased expression of interleukin-1beta and vascular cell adhesion molecule-1 was found as a biological indicator of TNF-alpha ligand-receptor interaction. Explanted tissues acquired destructive potential upon TNF-alpha stimulation, whereas TNF-alpha blockers controlled it in inflamed tissues. These findings suggest that, in pericoronitis, inflammatory and resident cells produce and respond to potent pro-inflammatory cytokine TNF-alpha, with pathogenic and potential therapeutic relevance.

  9. Alpha macroglobulins and the low-density-lipoprotein-related protein alpha-2-macroglobulin receptor in experimental renal fibrosis

    NARCIS (Netherlands)

    van Goor, H; Diamond, [No Value; Ding, GH; Kaysen, GA

    1999-01-01

    In this study, we evaluated the location of non-specific proteinase inhibitors and their receptor in experimental glomerular and interstitial fibrosis. The alpha macroglobulins alpha-2-macroglobulin (alpha 2M) and alpha-1-inhibitor 3 (alpha 1I3) are proteinase inhibitors, including

  10. Molecular identification of the insect adipokinetic hormone receptors

    DEFF Research Database (Denmark)

    Staubli, Frank; Jørgensen, Thomas J D; Cazzamali, Giuseppe

    2002-01-01

    The insect adipokinetic hormones (AKHs) are a large family of peptide hormones that are involved in the mobilization of sugar and lipids from the insect fat body during energy-requiring activities such as flight and locomotion, but that also contribute to hemolymph sugar homeostasis. Here, we have...... identified the first insect AKH receptors, namely those from the fruitfly Drosophila melanogaster and the silkworm Bombyx mori. These results represent a breakthrough for insect molecular endocrinology, because it will lead to the cloning of all AKH receptors from all model insects used in AKH research, and......, therefore, to a better understanding of AKH heterogeneity and actions. Interestingly, the insect AKH receptors are structurally and evolutionarily related to the gonadotropin-releasing hormone receptors from vertebrates....

  11. Agouti protein is an antagonist of the melanocyte-stimulating-hormone receptor.

    Science.gov (United States)

    Lu, D; Willard, D; Patel, I R; Kadwell, S; Overton, L; Kost, T; Luther, M; Chen, W; Woychik, R P; Wilkison, W O

    1994-10-27

    The genetic loci agouti and extension control the relative amounts of eumelanin (brown-black) and phaeomelanin (yellow-red) pigments in mammals: extension encodes the receptor for melanocyte-stimulating hormone (MSH) and agouti encodes a novel 131-amino-acid protein containing a signal sequence. Agouti, which is produced in the hair follicle, acts on follicular melanocytes to inhibit alpha-MSH-induced eumelanin production, resulting in the subterminal band of phaeomelanin often visible in mammalian fur. Here we use partially purified agouti protein to demonstrate that agouti is a high-affinity antagonist of the MSH receptor and blocks alpha-MSH stimulation of adenylyl cyclase, the effector through which alpha-MSH induces eumelanin synthesis. Agouti was also found to be an antagonist of the melanocortin-4 receptor, a related MSH-binding receptor. Consequently, the obesity caused by ectopic expression of agouti in the lethal yellow (Ay) mouse may be due to the inhibition of melanocortin receptor(s) outside the hair follicle.

  12. Hormones and receptors in fish: do duplicates matter?

    Science.gov (United States)

    Roch, Graeme J; Wu, Sheng; Sherwood, Nancy M

    2009-03-01

    Modern fish are the result of major changes in evolution including three possible duplications of the whole genome. Retained duplicate genes are often involved with metabolism, transcription, neurogenic processes and development. Here we examine the consequences of the most recent (350 mya) teleost-specific duplication in five fishes (zebrafish, fugu, medaka, stickleback and rainbow trout) in regard to duplicate copies of hormones and receptors in the secretin superfamily. This subset of genes was selected as the superfamily is limited to ten hormones and their receptors and includes some important members: glucagon, growth hormone-releasing hormone (GHRH), pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal polypeptide (VIP). We used reports from the literature and an extensive database search of the fish genomes to evaluate the status of the superfamily and its duplicate genes. We found that all five fish species have an almost complete set of orthologs with the human superfamily of hormones, although they lack secretin and its receptor. Receptor orthologs are present in zebrafish, fugu, medaka, stickleback and to a lesser extent in salmonids. Zebrafish retain duplicate copies for seven hormones and five receptors. Duplicated genes in fugu, medaka, stickleback and salmonids are also present, based mainly on genome annotation or mRNA transcription. Separate chromosome locations and synteny support zebrafish duplicates as the result of large-scale duplications. Novel changes in fish include the modification of a duplicate glucagon receptor to a GLP-1 receptor and, unlike humans, the presence of bioactive and specific PHI and GHRH-like peptide receptors. We conclude that fish duplicates in the secretin superfamily are a rich, mostly unexplored area for endocrine research.

  13. Ligands specify estrogen receptor alpha nuclear localization and degradation

    Directory of Open Access Journals (Sweden)

    Caze-Subra Stéphanie

    2010-12-01

    Full Text Available Abstract Background The estrogen receptor alpha (ERα is found predominately in the nucleus, both in hormone stimulated and untreated cells. Intracellular distribution of the ERα changes in the presence of agonists but the impact of different antiestrogens on the fate of ERα is a matter of debate. Results A MCF-7 cell line stably expressing GFP-tagged human ERα (SK19 cell line was created to examine the localization of ligand-bound GFP-ERα. We combined digitonin-based cell fractionation analyses with fluorescence and immuno-electron microscopy to determine the intracellular distribution of ligand-bound ERα and/or GFP-ERα. Using fluorescence- and electron microscopy we demonstrate that both endogenous ERα and GFP-ERα form numerous nuclear focal accumulations upon addition of agonist, 17β-estradiol (E2, and pure antagonists (selective estrogen regulator disruptor; SERD, ICI 182,780 or RU58,668, while in the presence of partial antagonists (selective estrogen regulator modulator; SERM, 4-hydroxytamoxifen (OHT or RU39,411, diffuse nuclear staining persisted. Digitonin based cell fractionation analyses confirmed that endogenous ERα and GFP-ERα predominantly reside in the nuclear fraction. Overall ERα protein levels were reduced after estradiol treatment. In the presence of SERMs ERα was stabilized in the nuclear soluble fraction, while in the presence of SERDs protein levels decreased drastically and the remaining ERα was largely found in a nuclear insoluble fraction. mRNA levels of ESR1 were reduced compared to untreated cells in the presence of all ligands tested, including E2. E2 and SERDs induced ERα degradation occurred in distinct nuclear foci composed of ERα and the proteasome providing a simple explanation for ERα sequestration in the nucleus. Conclusions Our results indicate that chemical structure of ligands directly affect the nuclear fate and protein turnover of the estrogen receptor alpha independently of their impact on

  14. Folate receptor {alpha} regulates cell proliferation in mouse gonadotroph {alpha}T3-1 cells

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Congjun; Evans, Chheng-Orn [Department of Neurosurgery and Laboratory of Molecular Neurosurgery and Biotechnology, Emory University, School of Medicine, Atlanta, Georgia (United States); Stevens, Victoria L. [Epidemiology and Surveillance Research, American Cancer Society, Atlanta, Georgia (United States); Owens, Timothy R. [Emory University, School of Medicine, Atlanta, Georgia (United States); Oyesiku, Nelson M., E-mail: noyesik@emory.edu [Department of Neurosurgery and Laboratory of Molecular Neurosurgery and Biotechnology, Emory University, School of Medicine, Atlanta, Georgia (United States)

    2009-11-01

    We have previously found that the mRNA and protein levels of the folate receptor alpha (FR{alpha}) are uniquely over-expressed in clinically human nonfunctional (NF) pituitary adenomas, but the mechanistic role of FR{alpha} has not fully been determined. We investigated the effect of FR{alpha} over-expression in the mouse gonadotroph {alpha}T3-1 cell line as a model for NF pituitary adenomas. We found that the expression and function of FR{alpha} were strongly up-regulated, by Western blotting and folic acid binding assay. Furthermore, we found a higher cell growth rate, an enhanced percentage of cells in S-phase by BrdU assay, and a higher PCNA staining. These observations indicate that over-expression of FR{alpha} promotes cell proliferation. These effects were abrogated in the same {alpha}T3-1 cells when transfected with a mutant FR{alpha} cDNA that confers a dominant-negative phenotype by inhibiting folic acid binding. Finally, by real-time quantitative PCR, we found that mRNA expression of NOTCH3 was up-regulated in FR{alpha} over-expressing cells. In summary, our data suggests that FR{alpha} regulates pituitary tumor cell proliferation and mechanistically may involve the NOTCH pathway. Potentially, this finding could be exploited to develop new, innovative molecular targeted treatment for human NF pituitary adenomas.

  15. The Alpha-1A Adrenergic Receptor in the Rabbit Heart.

    Directory of Open Access Journals (Sweden)

    R Croft Thomas

    Full Text Available The alpha-1A-adrenergic receptor (AR subtype is associated with cardioprotective signaling in the mouse and human heart. The rabbit is useful for cardiac disease modeling, but data on the alpha-1A in the rabbit heart are limited. Our objective was to test for expression and function of the alpha-1A in rabbit heart. By quantitative real-time reverse transcription PCR (qPCR on mRNA from ventricular myocardium of adult male New Zealand White rabbits, the alpha-1B was 99% of total alpha-1-AR mRNA, with <1% alpha-1A and alpha-1D, whereas alpha-1A mRNA was over 50% of total in brain and liver. Saturation radioligand binding identified ~4 fmol total alpha-1-ARs per mg myocardial protein, with 17% alpha-1A by competition with the selective antagonist 5-methylurapidil. The alpha-1D was not detected by competition with BMY-7378, indicating that 83% of alpha-1-ARs were alpha-1B. In isolated left ventricle and right ventricle, the selective alpha-1A agonist A61603 stimulated a negative inotropic effect, versus a positive inotropic effect with the nonselective alpha-1-agonist phenylephrine and the beta-agonist isoproterenol. Blood pressure assay in conscious rabbits using an indwelling aortic telemeter showed that A61603 by bolus intravenous dosing increased mean arterial pressure by 20 mm Hg at 0.14 μg/kg, 10-fold lower than norepinephrine, and chronic A61603 infusion by iPRECIO programmable micro Infusion pump did not increase BP at 22 μg/kg/d. A myocardial slice model useful in human myocardium and an anthracycline cardiotoxicity model useful in mouse were both problematic in rabbit. We conclude that alpha-1A mRNA is very low in rabbit heart, but the receptor is present by binding and mediates a negative inotropic response. Expression and function of the alpha-1A in rabbit heart differ from mouse and human, but the vasopressor response is similar to mouse.

  16. Alpha-MSH, the melanocortin-1 receptor and background adaptation in the Mozambique tilapia, Oreochromis mossambicus.

    Science.gov (United States)

    van der Salm, A L; Metz, J R; Bonga, S E Wendelaar; Flik, G

    2005-11-01

    The regulation of skin darkness in vertebrates is mediated by alpha-melanophore-stimulating-hormone (alphaMSH). For this action, alphaMSH binds to the melanocortin (MC)-1 receptor, a 7-transmembrane receptor located in melanophore cell membranes. The Mozambique tilapia, Oreochromis mossambicus, can change the hue of its body in response to a change in background, a process that may involve alphaMSH and the MC1R. Scale melanophores were isolated from tilapia that were acclimatised for 25 days to a black, control grey or white background and then tested for their sensitivity to des-, mono-, and di-acetylated alphaMSH. On all backgrounds, mono-acetylated alphaMSH was the dominant isoform present in pituitary homogenates. Mono-acetylated alphaMSH also had the highest potency to disperse melanosomes. Black background adapted fish showed the highest dispersing response to alphaMSH, independent of the isoform applied. We elucidated the nucleotide and amino acid sequence of the tilapia MC1R. We show that its expression in skin does not change when tilapia are acclimatised for 25 days to a black, grey or white background, while a clear change in hue is visible. This finding, combined with the absence of differential MC1R gene expression following background acclimation indicates that the increased sensitivity to alphaMSH is most likely a result of changes in the intracellular signalling system in melanophores of black background adapted fish, rather than up-regulation of the MC1R.

  17. Mitigating photosensitivity of erythropoietic protoporphyria patients by an agonistic analog of alpha-melanocyte stimulating hormone.

    Science.gov (United States)

    Harms, Juergen H; Lautenschlager, Stephan; Minder, Christoph E; Minder, Elisabeth I

    2009-01-01

    Erythropoietic protoporphyria (EPP) is a rare hereditary disorder characterized by dermal accumulation of the photosensitizer protoporphyrin IX. Following sunlight exposure, the resulting photosensitivity is manifested first as pain, later as erythema, edema and dermal lesions. Afamelanotide (Nle(4)-D-Phe(7)-alpha-MSH), a synthetic analog of alpha-melanocyte stimulating hormone and agonist of the melanocortin-1-receptor, promotes melanin synthesis, increasing skin pigmentation. This study examines the efficacy of afamelanotide in preventing symptoms in patients with EPP. A sustained-release subcutaneous implant of 20 mg afamelanotide was administered twice, with a 60-day interval to five EPP patients. Therapeutic efficacy was assessed by a photoprovocation test using standardized white light irradiation, melanin density (MD) determination and daily recording of sunlight exposure and symptoms. From Day 30 to Day 120 tolerance to photoprovocation significantly increased compared with baseline (P = 0.007) and skin MD was significantly higher than that recorded at baseline (P = 0.004). Except for two low-grade pain episodes, patients recorded no phototoxic events past Day 4 of treatment. Tolerance to natural sunlight was up to 24 times longer than prior to therapy. The findings demonstrate beneficial effects of afamelanotide in patients with EPP. Due to the limited number of patients enrolled and the design being an open-label study, confirmation by a large-scale trial is required.

  18. The effects of acute and chronic alpha melanocyte stimulating hormone (alphaMSH) on cardiovascular dynamics in conscious rats.

    Science.gov (United States)

    Hill, Crystal; Dunbar, Joseph C

    2002-09-01

    Alpha melanocyte stimulating hormone (alphaMSH) has been demonstrated to have regulatory functions in the periphery and central nervous system (CNS). alphaMSH plays a central role in the regulation of metabolic balance such as decreasing food intake, increasing sympathetic outflow and hypothalamic/pituitary function. Our laboratory has investigated the actions of alphaMSH on sympathetic and cardiovascular dynamics using anesthetized animals. In this study we determined both the acute and chronic effects of alphaMSH on cardiovascular and metabolic dynamics in conscious unrestrained rats. Animals were each implanted with a radio-telemetry transmitter for recording of cardiovascular parameters and subsequently instrumented with intracerebroventricular (ICV) cannulas. The acute ICV administration of alphaMSH significantly increased the mean arterial pressure (MAP) and heart rate (HR) when compared to artificial cerebrospinal fluid (ACSF) controls. On the other hand chronic alphaMSH infusion resulted in an initial increase in MAP and HR lasting for 2 days followed by a decrease in MAP. Chronic alphaMSH administration decreased physical activity and food intake but not weight gain. We conclude that in the conscious unrestrained animal the acute administration of alphaMSH increased MAP and HR, however, chronic infusion is associated with decreased MAP, physical activity and food intake.

  19. Synthesis of Analogues of Thyroid Hormones: Nuclear Receptor Modulators

    Directory of Open Access Journals (Sweden)

    Guilherme Vieira de Castro

    2015-09-01

    Full Text Available Thyroid hormones are essential for the development and differentiation of all cells of the human body. This work reports the synthesis of some synthetic structural analogues of thyroid hormones, which may be modulators of the thyroid hormone receptor. The known compounds GC-1 (Sobetirome and CG-24 were successfully prepared and two novel analogous molecules were also synthesized by a new and efficient synthetic methodology. DOI: http://dx.doi.org/10.17807/orbital.v7i3.739  

  20. Endocrine control of canine mammary neoplasms: serum reproductive hormone levels and tissue expression of steroid hormone, prolactin and growth hormone receptors.

    Science.gov (United States)

    Spoerri, Michèle; Guscetti, Franco; Hartnack, Sonja; Boos, Alois; Oei, Christine; Balogh, Orsolya; Nowaczyk, Renata M; Michel, Erika; Reichler, Iris M; Kowalewski, Mariusz P

    2015-09-15

    Neoplasms of the mammary gland are among the most common diseases in female domestic dogs (Canis familiaris). It is assumed that reproductive hormones influence tumorigenesis in this species, although the precise role of the endocrine milieu and reproductive state is subject to continuing discussion. In line with this, a recent systematic review of available data on the development of mammary neoplasms revealed weak evidence for risk reduction after neutering and an effect of age at neutering. Investigation of several hormone receptors has revealed decreased expression of estrogen receptor-alpha (ERα, ESR1), progesterone (P4) receptor (PGR), prolactin (PRL) receptor (PRLR) and growth hormone receptor (GHR) associated with neoplastic differentiation of mammary tissues. In other studies, increased levels of estrogens, progesterone and prolactin were found in serum and/or tissue homogenates of dogs with malignant neoplasms. However, the association between these entities within one animal population was never previously examined. Therefore, this study investigated the association between circulating serum concentrations of estradiol-17β, progesterone and prolactin, and gene expression of ERα (ESR1), ERβ (ESR2), PGR, PRLR, PRL and GHR, with respect to reproductive state (spayed vs. intact) and cycle stage (anestrus vs. diestrus). Additionally, the expression of E-cadherin (CDH-1) was evaluated as a possible indicator of metastatic potential. For all receptors, the lowest gene expression was found in malignant tumors compared to normal tissues of affected dogs. Steroid levels were not influenced by their corresponding receptor expression in mammary neoplasms, but increased PRL levels were negatively associated with low PRLR gene expression in malignant tumors. The expression of CDH-1 was influenced by tumor malignancy and cycle stage, i.e., the highest gene expression was found in benign mammary tumors in diestrous dogs compared to normal and malignant mammary

  1. Discovery of an Oxybenzylglycine Based Peroxisome Proliferator Activated Receptor Alpha Selective

    Energy Technology Data Exchange (ETDEWEB)

    Li, J.; Kennedy, L; Shi, Y; Tao, S; Ye, X; Chen, S; Wang, Y; Hernandez, A; Wang, W; et al.

    2010-01-01

    An 1,3-oxybenzylglycine based compound 2 (BMS-687453) was discovered to be a potent and selective peroxisome proliferator activated receptor (PPAR) {alpha} agonist, with an EC{sub 50} of 10 nM for human PPAR{alpha} and {approx}410-fold selectivity vs human PPAR{gamma} in PPAR-GAL4 transactivation assays. Similar potencies and selectivity were also observed in the full length receptor co-transfection assays. Compound 2 has negligible cross-reactivity against a panel of human nuclear hormone receptors including PPAR{delta}. Compound 2 demonstrated an excellent pharmacological and safety profile in preclinical studies and thus was chosen as a development candidate for the treatment of atherosclerosis and dyslipidemia. The X-ray cocrystal structures of the early lead compound 12 and compound 2 in complex with PPAR{alpha} ligand binding domain (LBD) were determined. The role of the crystal structure of compound 12 with PPAR{alpha} in the development of the SAR that ultimately resulted in the discovery of compound 2 is discussed.

  2. Estrogen activates rapid signaling in the brain: role of estrogen receptor alpha and estrogen receptor beta in neurons and glia.

    Science.gov (United States)

    Mhyre, A J; Dorsa, D M

    2006-01-01

    The aging process is known to coincide with a decline in circulating sex hormone levels in both men and women. Due to an increase in the average lifespan, a growing number of post-menopausal women are now receiving hormone therapy for extended periods of time. Recent findings of the Women's Health Initiative, however, have called into question the benefits of long-term hormone therapy for treating symptoms of menopause. The results of this study are still being evaluated, but it is clear that a better understanding of the molecular effects of estradiol is needed in order to develop new estrogenic compounds that activate specific mechanisms but lack adverse side effects. Traditionally, the effects of estradiol treatment have been ascribed to changes in gene expression, namely transcription at estrogen response elements. This review focuses on emerging information that estradiol can also activate a repertoire of membrane-initiated signaling pathways and that these rapid signaling events lead to functional changes at the cellular level. The various types of cells in the brain can respond differently to estradiol treatment based on the signaling properties of the cell, as well as which receptor, estrogen receptor alpha and/or estrogen receptor beta, is expressed. Taken together, these findings suggest that the estradiol-induced activation of membrane-initiated signaling pathways occurs in a cell-type specific manner and can differentially influence how the cells respond to various insults.

  3. Steroid hormone receptors in male breast diseases.

    Science.gov (United States)

    Pacheco, M M; Oshima, C F; Lopes, M P; Widman, A; Franco, E L; Brentani, M M

    1986-01-01

    Estrogen (ER), progesterone (PR), glucocorticoid (GR) and androgen (AR) receptors were assayed in tumor samples from 8 cases of male breast cancer (MBC) and 20 cases of male gynecomastia. Seven out of eight (87.5%) male tumor samples had positive ER assays with values ranging from 12 to 180 fmol/mg protein. Of the seven ER positive cases of MBC, six, had positive PR activity with high titers. Positive GR and AR values were also detected in 75% of MBC cases. Concentrations of all four receptors were significantly correlated with each other. With gynecomastic tissue, the proportion of receptor-positive patients was 20% ER, 20% PR, 20% AR, and 45% GR. Except for GR, steroid receptor values for MBC individuals were significantly higher than those of gynecomastia patients.

  4. Model for growth hormone receptor activation based on subunit rotation within a receptor dimer

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Richard J.; Adams, Julian J.; Pelekanos, Rebecca A.; Wan, Yu; McKinstry, William J.; Palethorpe, Kathryn; Seeber, Ruth M.; Monks, Thea A.; Eidne, Karin A.; Parker, Michael W.; Waters, Michael J. (UWA); (St. Vincent); (Queensland)

    2010-07-13

    Growth hormone is believed to activate the growth hormone receptor (GHR) by dimerizing two identical receptor subunits, leading to activation of JAK2 kinase associated with the cytoplasmic domain. However, we have reported previously that dimerization alone is insufficient to activate full-length GHR. By comparing the crystal structure of the liganded and unliganded human GHR extracellular domain, we show here that there is no substantial change in its conformation on ligand binding. However, the receptor can be activated by rotation without ligand by inserting a defined number of alanine residues within the transmembrane domain. Fluorescence resonance energy transfer (FRET), bioluminescence resonance energy transfer (BRET) and coimmunoprecipitation studies suggest that receptor subunits undergo specific transmembrane interactions independent of hormone binding. We propose an activation mechanism involving a relative rotation of subunits within a dimeric receptor as a result of asymmetric placement of the receptor-binding sites on the ligand.

  5. Receptors for thyrotropin-releasing hormone, thyroid-stimulating hormone, and thyroid hormones in the macaque uterus: effects of long-term sex hormone treatment.

    Science.gov (United States)

    Hulchiy, Mariana; Zhang, Hua; Cline, J Mark; Hirschberg, Angelica Lindén; Sahlin, Lena

    2012-11-01

    Thyroid gland dysfunction is associated with menstrual cycle disturbances, infertility, and increased risk of miscarriage, but the mechanisms are poorly understood. However, little is known about the regulation of these receptors in the uterus. The aim of this study was to determine the effects of long-term treatment with steroid hormones on the expression, distribution, and regulation of the receptors for thyrotropin-releasing hormone (TRHR) and thyroid-stimulating hormone (TSHR), thyroid hormone receptor α1/α2 (THRα1/α2), and THRβ1 in the uterus of surgically menopausal monkeys. Eighty-eight cynomolgus macaques were ovariectomized and treated orally with conjugated equine estrogens (CEE; n = 20), a combination of CEE and medroxyprogesterone acetate (MPA; n = 20), or tibolone (n = 28) for 2 years. The control group (OvxC; n = 20) received no treatment. Immunohistochemistry was used to evaluate the protein expression and distribution of the receptors in luminal epithelium, glands, stroma, and myometrium of the uterus. Immunostaining of TRHR, TSHR, and THRs was detected in all uterine compartments. Epithelial immunostaining of TRHR was down-regulated in the CEE + MPA group, whereas in stroma, both TRHR and TSHR were increased by CEE + MPA treatment as compared with OvxC. TRHR immunoreactivity was up-regulated, but THRα and THRβ were down-regulated, in the myometrium of the CEE and CEE + MPA groups. The thyroid-stimulating hormone level was higher in the CEE and tibolone groups as compared with OvxC, but the level of free thyroxin did not differ between groups. All receptors involved in thyroid hormone function are expressed in monkey uterus, and they are all regulated by long-term steroid hormone treatment. These findings suggest that there is a possibility of direct actions of thyroid hormones, thyroid-stimulating hormone and thyrotropin-releasing hormone on uterine function.

  6. Metastatic Breast Cancer and Hormonal Receptor Status among a ...

    African Journals Online (AJOL)

    Background: Breast cancer is the third commonest cancer in women in Uganda. The majority of breast cancer patients in Uganda present with advanced disease. Many studies show that metastatic lesions frequently lodge in bones, lung and liver. Tumour hormone receptor status correlates with site of metastatic lesions and ...

  7. Genetic features of thyroid hormone receptors

    Indian Academy of Sciences (India)

    region of chromosome 3 and variable deletion in small cell lung cancer. Proc. Natl. Acad. Sci. USA 85, 9258–9262. Duan Q. L., Du R., Lasky-Su J., Klanderman B. J., Partch A. B.,. Peters S. P. et al. 2012 A polymorphism in the thyroid hor- mone receptor gene is associated with bronchodilator response in asthmatics Duan.

  8. Tetrahydro-iso-alpha Acids Antagonize Estrogen Receptor Alpha Activity in MCF-7 Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Maëlle Lempereur

    2016-01-01

    Full Text Available Tetrahydro-iso-alpha acids commonly called THIAA or Tetra are modified hop acids extracted from hop (Humulus lupulus L. which are frequently used in brewing industry mainly in order to provide beer bitterness and foam stability. Interestingly, molecular structure of tetrahydro-iso-alpha acids is close to a new type of estrogen receptor alpha (ERα antagonists aimed at disrupting the binding of coactivators containing an LxxLL motif (NR-box. In this work we show that THIAA decreases estradiol-stimulated proliferation of MCF-7 (ERα-positive breast cancer cells. Besides, we show that it inhibits ERα transcriptional activity. Interestingly, this extract fails to compete with estradiol for ERα binding and does not significantly impact the receptor turnover rate in MCF-7 cells, suggesting that it does not act like classical antiestrogens. Hence, we demonstrate that THIAA is able to antagonize ERα estradiol-induced recruitment of the LxxLL binding motif.

  9. Growth hormone action in rat insulinoma cells expressing truncated growth hormone receptors

    DEFF Research Database (Denmark)

    Møldrup, Annette; Allevato, G; Dyrberg, Thomas

    1991-01-01

    Transfection of the insulin-producing rat islet tumor cell line RIN-5AH with a full length cDNA of the rat hepatic growth hormone (GH) receptor (GH-R1-638) augments the GH-responsive insulin synthesis in these cells. Using this functional system we analyzed the effect of COOH-terminal truncation...

  10. Alpha2 subunit specificity of cyclothiazide inhibition on glycine receptors.

    Science.gov (United States)

    Zhang, Xiao-Bing; Sun, Guang-Chun; Liu, Lu-Ying; Yu, Fang; Xu, Tian-Le

    2008-04-01

    In the mammalian cortex, alpha2 subunit-containing glycine receptors (GlyRs) mediate tonic inhibition, but the precise functional role of this type of GlyRs is difficult to establish because of the lack of subtype-selective antagonist. In this study, we found that cyclothiazide (CTZ), an epileptogenic agent, potently inhibited GlyR-mediated current (I(Gly)) in cultured rat hippocampal neurons. The inhibition was glycine concentration-dependent, suggesting a competitive mechanism. Note that GlyRs containing the alpha2 but not alpha1 or alpha3 subunits, when being heterologously expressed in human embryonic kidney 293T cells, were inhibited by CTZ, indicating subunit specificity of CTZ action. In addition, the degree of CTZ inhibition on I(Gly) in rat spinal neurons declined with time in culture, in parallel with a decline of alpha2 subunit expression, which is known to occur during spinal cord development. Furthermore, site-directed mutagenesis indicates that a single-amino acid threonine at position 59 near the N terminus of the alpha2 subunit confers the specificity of CTZ action. Thus, CTZ is a potent and selective inhibitor of alpha2-GlyRs, and threonine at position 59 plays a critical role in the susceptibility of GlyR to CTZ inhibition.

  11. The Growth Hormone Secretagogue Receptor: Its Intracellular Signaling and Regulation

    Science.gov (United States)

    Yin, Yue; Li, Yin; Zhang, Weizhen

    2014-01-01

    The growth hormone secretagogue receptor (GHSR), also known as the ghrelin receptor, is involved in mediating a wide variety of biological effects of ghrelin, including: stimulation of growth hormone release, increase of food intake and body weight, modulation of glucose and lipid metabolism, regulation of gastrointestinal motility and secretion, protection of neuronal and cardiovascular cells, and regulation of immune function. Dependent on the tissues and cells, activation of GHSR may trigger a diversity of signaling mechanisms and subsequent distinct physiological responses. Distinct regulation of GHSR occurs at levels of transcription, receptor interaction and internalization. Here we review the current understanding on the intracellular signaling pathways of GHSR and its modulation. An overview of the molecular structure of GHSR is presented first, followed by the discussion on its signaling mechanisms. Finally, potential mechanisms regulating GHSR are reviewed. PMID:24651458

  12. Nuclear hormone receptor architecture - form and dynamics: The 2009 FASEB Summer Conference on Dynamic Structure of the Nuclear Hormone Receptors.

    Science.gov (United States)

    McEwan, Iain J; Nardulli, Ann M

    2009-12-31

    Nuclear hormone receptors (NHRs) represent a large and diverse family of ligand-activated transcription factors involved in regulating development, metabolic homeostasis, salt balance and reproductive health. The ligands for these receptors are typically small hydrophobic molecules such as steroid hormones, thyroid hormone, vitamin D3 and fatty acid derivatives. The first NHR structural information appeared approximately 20 years ago with the solution and crystal structures of the DNA binding domains and was followed by the structure of the agonist and antagonist bound ligand binding domains of different NHR members. Interestingly, in addition to these defined structural features, it has become clear that NHRs also possess significant structural plasticity. Thus, the dynamic structure of the NHRs was the topic of a recent stimulating and informative FASEB Summer Research Conference held in Vermont.

  13. Growth of human prostate carcinomas with and without hormone alpha- dehydrotestosterone in nude mice.

    Science.gov (United States)

    Baisch, H; Otto, U; Fack, H

    1998-12-01

    The dependence of human prostate carcinoma growth on hormone was studied in xenotransplants in nude mice. The objective was to determine differences in cell kinetic parameters and volume growth of tumors growing with alpha-dehydrotestosterone (alphaDHT) and without alphaDHT. These differences could be used as arguments pro and contra the adaptation versus the clonal selection hypothesis. Human prostate carcinomas were xenotransplanted into nude mice. Growth of tumors was observed in castrated male mice without and with implanted osmotic pumps secreting alphaDHT. In a further series of experiments the alphaDHT tubes were removed when the tumors had reached a volume of 0.3 cm3. Tumor volume was measured to determine tumor doubling time with and without alphaDHT. Detailed cell kinetics were analyzed using the bromodeoxyuridine (BrdUrd) method with flow cytometry. Applying the relative movement (RM) and a simulation analysis to parallel single and multiple BrdUrd labelling experimental data we determined transit times through the phases of cell cycle, potential doubling time Tpot, growth fraction (GF) and cell loss. Five human prostate carcinomas were xenotransplanted into nude mice. Tumor take was only achieved when androgen hormone was present. However, when alphaDHT was removed when the tumors had grown to a volume of 0.3 cm3, they continued to grow at nearly the same Td as those tumors with continued alphaDHT application. The BrdUrd experiments, on the other hand, showed considerable increase of Tc and Tpot upon withdrawal of alphaDHT in 4 out of 5 tumors. The GF and labelling index (LI) were maintained at about the same level as alphaDHT consuming tumors. While small transplanted tumor pieces do not grow without alphaDHT, larger tumors grow with the same Td after removal of alphaDHT. The slower proliferation shown by the increased Tc and Tpot is balanced by less cell loss. Since GF and LI were maintained at about the same level, we conclude that in our tumors the

  14. Expression of functional growth hormone receptor in a mouse L cell line infected with recombinant vaccinia virus

    NARCIS (Netherlands)

    Strous, G J; van Kerkhof, P; Verheijen, C; Rossen, J W; Liou, W; Slot, J W; Roelen, C A; Schwartz, A L

    The growth hormone receptor is a member of a large family of receptors including the receptors for prolactin and interleukins. Upon binding to one molecule of growth hormone two growth hormone receptor polypeptides dimerize. We have expressed the rabbit growth hormone receptor DNA in transfected

  15. Estrogen receptor alpha and risk for cognitive impairment in postmenopausal women

    DEFF Research Database (Denmark)

    Olsen, Line; Rasmussen, Henrik B; Hansen, Thomas

    2006-01-01

    -item Orientation-Memory-Concentration test in postmenopausal Danish women. Hormone replacement therapy, age and executive cognitive ability were examined as covariates for ESR1 gene effects on cognitive impairment. The XbaI polymorphism showed a marginal effect on cognitive abilities (P=0.054) when adjusted......The estrogen receptor alpha (ESR1) gene has been implicated in the process of cognitive impairment in elderly women. In a paired case-control study, we tested whether two ESR1 gene polymorphisms (the XbaI and PvuII sites) are risk factors for cognitive impairment as measured by the six...... for executive cognitive ability. Using a dominant genetic model for the X allele, we found an elevated risk (executive cognitive ability adjusted P=0.033) for cognitive impairment. Hormone replacement therapy also had a borderline effect on cognitive ability (P=0.049) and this effect was reflected in executive...

  16. The size of the thyroid hormone receptor in chromatin.

    Science.gov (United States)

    Gruol, D J; Kempner, E S

    1982-01-25

    We have used radiation inactivation and target theory to determine the size of the functional unit for T3 binding in rat liver chromatin. The process involves exposure of frozen chromatin samples to a beam of high energy electrons produced in a linear accelerator and subsequent measurement of the residual capacity to bind hormone. Our experiments were carried out using three forms of solubilized chromatin: 1) sonicated, containing the receptor in fragments which sedimented faster than 30 S; 2) digested by nuclease, containing the receptor in a form which sedimented at 5-6 S; 3) digested by nuclease and made 0.5 M in KCl, containing the receptor in a form which sedimented at 3.8 S. We have shown that in each sample preparation the receptor retained the ability to bind T3 with the same capacity and affinity that had previously been measured with high molecular weight chromatin. Irradiation caused a reduction in the capacity to bind T3 but did not change the affinity of the remaining receptors for the hormone. In each preparation, the radiation resulted in a simple exponential loss of binding capacity with dose, indicating that a single target size was detected. Within the variation of the measurements, the target size for each form of the receptor was the same, 59,000 daltons.

  17. Sex Hormones and Their Receptors Regulate Liver Energy Homeostasis

    Directory of Open Access Journals (Sweden)

    Minqian Shen

    2015-01-01

    Full Text Available The liver is one of the most essential organs involved in the regulation of energy homeostasis. Hepatic steatosis, a major manifestation of metabolic syndrome, is associated with imbalance between lipid formation and breakdown, glucose production and catabolism, and cholesterol synthesis and secretion. Epidemiological studies show sex difference in the prevalence in fatty liver disease and suggest that sex hormones may play vital roles in regulating hepatic steatosis. In this review, we summarize current literature and discuss the role of estrogens and androgens and the mechanisms through which estrogen receptors and androgen receptors regulate lipid and glucose metabolism in the liver. In females, estradiol regulates liver metabolism via estrogen receptors by decreasing lipogenesis, gluconeogenesis, and fatty acid uptake, while enhancing lipolysis, cholesterol secretion, and glucose catabolism. In males, testosterone works via androgen receptors to increase insulin receptor expression and glycogen synthesis, decrease glucose uptake and lipogenesis, and promote cholesterol storage in the liver. These recent integrated concepts suggest that sex hormone receptors could be potential promising targets for the prevention of hepatic steatosis.

  18. Steroidal Hormone Receptor Expression in Male Breast Cancer

    Directory of Open Access Journals (Sweden)

    Fatemeh Homaei-Shandiz

    2014-01-01

    Full Text Available Introduction: The etiology of male breast cancer is unclear, but hormonal levels may play a role in development of this disease. It seems that the risk of male breast cancer related to increased lifelong exposure to estrogen or reduced androgen. The aim of this study was to investigate the expression of the steroid hormone receptors including estrogen receptor (ER and progesterone receptor (PR in Iranian cases with male breast cancer. Methods: This is a prospective review of 18 cases of male breast cancer in in Omid Hospital, Mashhad, North East of Iran, between October 2001 and October 2006. ER and PR were measured by immunohistochemistry. Clinicopathologic features and family history were obtained by interview. Data were analyzed with SPSS 13 using descriptive statistics.  Results: The median age was 63.2 year. All the cases were infiltrating ductal carcinoma. A high rate of expression of ER (88.8% and PR (66.6% was found in the studied cases. Conclusion: Cancers of the male breast are significantly more likely than cancers of the female breast to express hormonal receptors.

  19. Substantial expression of luteinizing hormone-releasing hormone (LHRH) receptor type I in human uveal melanoma

    Science.gov (United States)

    Schally, Andrew V.; Block, Norman L; Dezso, Balazs; Olah, Gabor; Rozsa, Bernadett; Fodor, Klara; Buglyo, Armin; Gardi, Janos; Berta, Andras; Halmos, Gabor

    2013-01-01

    Uveal melanoma is the most common primary intraocular malignancy in adults, with a very high mortality rate due to frequent liver metastases. Consequently, the therapy of uveal melanoma remains a major clinical challenge and new treatment approaches are needed. For improving diagnosis and designing a rational and effective therapy, it is essential to elucidate molecular characteristics of this malignancy. The aim of this study therefore was to evaluate as a potential therapeutic target the expression of luteinizing hormone-releasing hormone (LHRH) receptor in human uveal melanoma. The expression of LHRH ligand and LHRH receptor transcript forms was studied in 39 human uveal melanoma specimens by RT-PCR using gene specific primers. The binding charachteristics of receptors for LHRH on 10 samples were determined by ligand competition assays. The presence of LHRH receptor protein was further evaluated by immunohistochemistry. The expression of mRNA for type I LHRH receptor was detected in 18 of 39 (46%) of tissue specimens. mRNA for LHRH-I ligand could be detected in 27 of 39 (69%) of the samples. Seven of 10 samples investigated showed high affinity LHRH-I receptors. The specific presence of full length LHRH receptor protein was further confirmed by immunohistochemistry. A high percentage of uveal melanomas express mRNA and protein for type-I LHRH receptors. Our results support the merit of further investigation of LHRH receptors in human ophthalmological tumors. Since diverse analogs of LHRH are in clinical trials or are already used for the treatment of various cancers, these analogs could be considered for the LHRH receptor-based treatment of uveal melanoma. PMID:24077773

  20. Transcriptional activation by the thyroid hormone receptor through ligand-dependent receptor recruitment and chromatin remodelling

    DEFF Research Database (Denmark)

    Grøntved, Lars; Waterfall, Joshua J; Kim, Dong Wook

    2015-01-01

    A bimodal switch model is widely used to describe transcriptional regulation by the thyroid hormone receptor (TR). In this model, the unliganded TR forms stable, chromatin-bound complexes with transcriptional co-repressors to repress transcription. Binding of hormone dissociates co-repressors and...... process. This dynamic and ligand-dependent interaction with chromatin is likely shared by all steroid hormone receptors regardless of their capacity to repress transcription in the absence of ligand.......A bimodal switch model is widely used to describe transcriptional regulation by the thyroid hormone receptor (TR). In this model, the unliganded TR forms stable, chromatin-bound complexes with transcriptional co-repressors to repress transcription. Binding of hormone dissociates co......-repressors and facilitates recruitment of co-activators to activate transcription. Here we show that in addition to hormone-independent TR occupancy, ChIP-seq against endogenous TR in mouse liver tissue demonstrates considerable hormone-induced TR recruitment to chromatin associated with chromatin remodelling and activated...

  1. Hormonal regulation of AMPA receptor trafficking and memory formation

    Directory of Open Access Journals (Sweden)

    Harmen J Krugers

    2009-10-01

    Full Text Available Humans and rodents retain memories for stressful events very well. The facilitated retention of these memories is normally very useful. However, in susceptible individuals a variety of pathological conditions may develop in which memories related to stressful events remain inappropriately present, such as in post-traumatic stress disorder. The memory enhancing effects of stress are mediated by hormones, such as norepinephrine and glucocorticoids which are released during stressful experiences. Here we review recently identified molecular mechanisms that underlie the effects of stress hormones on synaptic efficacy and learning and memory. We discuss AMPA receptors as major target for stress hormones and describe a model in which norepinephrine and glucocorticoids are able to strengthen and prolong different phases of stressful memories.

  2. Molecular cloning and function expression of a diuretic hormone receptor from the house cricket, Acheta domesticus.

    Science.gov (United States)

    Reagan, J D

    1996-01-01

    Insect diuretic hormones regulate fluid and ion secretion and the receptors with which they interact are attractive targets for new insect control agents. Recently, a diuretic hormone receptor from the moth Manduca sexta was isolated by expression cloning and found to be a member of the calcitonin/secretin/corticotropin releasing factor family of G-protein coupled receptors [Reagan J. D. (1994) J. Biol. Chem. 269, 9-12]. Degenerate oligonucleotides were designed based upon conserved regions in this receptor family and used to isolate a diuretic hormone receptor from the house cricket, Acheta domesticus. The complementary DNA isolated encodes a protein consisting of 441 amino acids with seven putative membrane spanning regions. Interestingly, unlike the M. sexta diuretic hormone receptor, the cricket diuretic hormone receptor contains a putative signal sequence. The receptor shares 53% and 38% sequence identity with the M. sexta diuretic hormone and human corticotropin releasing factor receptors respectively. When expressed in COS-7 cells, the receptor binds A. domesticus diuretic hormone with high affinity and stimulates adenylate cyclase with high potency. Four other insect diuretic hormones are considerably less effective at stimulating adenylate cyclase in COS-7 cells transfected with the receptor. This is in contrast to the M. sexta diuretic hormone receptor which is stimulated by all five insect diuretic hormones with high potency.

  3. Studies using the estrogen receptor alpha knockout uterus demonstrate that implantation but not decidualization-associated signaling is estrogen dependent.

    Science.gov (United States)

    Curtis Hewitt, Sylvia; Goulding, Eugenia H; Eddy, E M; Korach, Kenneth S

    2002-10-01

    Ovarian hormonal signaling is essential for proper functioning of the uterus in the establishment of pregnancy. Previous studies have demonstrated that decidualization, a stromal transformation that occurs in response to embryo implantation, can be elicited in the uterus of estrogen receptor alpha knockout (alphaERKO) mice in the absence of the estrogen dependence normally seen in wild-type (WT) mice for this response. While the alphaERKO stromal compartment demonstrated the necessary decidual response, embryo implantation is a process initiated in the epithelial layer, a uterine component that lacks estrogen responsiveness in the alphaERKO. To determine if the alphaERKO uterus would be competent for implantation, donor embryos were transferred into the uterine lumen of WT and alphaERKO females that had been ovariectomized and treated with exogenous estradiol and progesterone to mimic early pregnancy. No implantation occurred in the alphaERKO, while implantation sites containing live embryos were seen in similarly treated WT uteri, indicating that functional estrogen receptor alpha (ERalpha) is required for implantation. Previous observations of estrogen-independent decidualization in the alphaERKO prompted investigation of the mechanism leading to estrogen independence of this process. The disruption of progesterone receptor (PR), Hoxa10, Cox2, or LIF in transgenic mice results in the loss of decidualization response. Therefore, the expression of these genes was studied in WT and alphaERKO uteri by comparing expression following vehicle, progesterone alone (P), or estradiol priming followed by progesterone with nidatory estradiol (E+Pe) and by comparing expression following the above hormonal manipulations in addition to luminal infusion of oil used previously as decidualization-initiating stimulus. The whole-uterus level of PR and Hoxa10 mRNAs did not vary; however, the PR protein was induced in the stroma 24 h after oil infusion. Interestingly, in the WT, this

  4. Sex Steroid Hormone Receptor Expression Affects Ovarian Cancer Survival

    DEFF Research Database (Denmark)

    Jönsson, Jenny-Maria; Skovbjerg Arildsen, Nicolai; Malander, Susanne

    2015-01-01

    in epithelial ovarian cancer. METHODS: Immunohistochemical stainings for ERα, ERβ, PR, and AR were assessed in relation to survival in 118 serous and endometrioid ovarian cancers. Expression of the genes encoding the four receptors was studied in relation to prognosis in the molecular subtypes of ovarian cancer...... in ovarian cancer and support that tumors should be stratified based on molecular as well as histological subtypes in future studies investigating the role of endocrine treatment in ovarian cancer.......BACKGROUND AND AIMS: Although most ovarian cancers express estrogen (ER), progesterone (PR), and androgen (AR) receptors, they are currently not applied in clinical decision making. We explored the prognostic impact of sex steroid hormone receptor protein and mRNA expression on survival...

  5. Inhibition of MAP kinase promotes the recruitment of corepressor SMRT by tamoxifen-bound estrogen receptor alpha and potentiates tamoxifen action in MCF-7 cells

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Wei, E-mail: hongwei@tijmu.edu.cn [Department of Immunology, Tianjin Medical University, 300070 Tianjin (China); Department of Laboratory Medicine, Tianjin Medical University, 300070 Tianjin (China); Chen, Linfeng [Department of Medical Oncology, Harvard Medical School, Dana Farber Cancer Institute, Boston, 02115 MA (United States); Li, Juan [Department of Laboratory Medicine, Tianjin Medical University, 300070 Tianjin (China); Yao, Zhi [Department of Immunology, Tianjin Medical University, 300070 Tianjin (China)

    2010-05-28

    Estrogen receptor alpha (ER{alpha}), a ligand controlled transcription factor, plays an important role in breast cancer growth and endocrine therapy. Tamoxifen (TAM) antagonizes ER{alpha} activity and has been applied in breast cancer treatment. TAM-bound ER{alpha} associates with nuclear receptor-corepressors. Mitogen-activated protein kinase (MAPK) has been elucidated to result in cross-talk between growth factor and ER{alpha} mediated signaling. We show that activated MAPK represses interaction of TAM-bound ER{alpha} with silencing mediator for retinoid and thyroid hormone receptors (SMRT) and inhibits the recruitment of SMRT by ER{alpha} to certain estrogen target genes. Blockade of MAPK signaling cascade with MEK inhibitor U0126 promotes the interaction and subsequently inhibits ER{alpha} activity via enhanced recruitment of SMRT, leading to reduced expression of ER{alpha} target genes. The growth rate of MCF-7 cells was decelerated when treated with both TAM and U0126. Moreover, the growth of MCF-7 cells stably expressing SMRT showed a robust repression in the presence of TAM and U0126. These results suggest that activated MAPK signaling cascade attenuates antagonist-induced recruitment of SMRT to ER{alpha}, suggesting corepressor mediates inhibition of ER{alpha} transactivation and breast cancer cell growth by antagonist. Taken together, our finding indicates combination of antagonist and MAPK inhibitor could be a helpful approach for breast cancer therapy.

  6. A novel steroidal inhibitor of estrogen-related receptor alpha (ERR alpha).

    Science.gov (United States)

    Duellman, Sarah J; Calaoagan, Joy M; Sato, Barbara G; Fine, Richard; Klebansky, Boris; Chao, Wan-Ru; Hobbs, Peter; Collins, Nathan; Sambucetti, Lidia; Laderoute, Keith R

    2010-09-15

    The orphan nuclear receptor estrogen-related receptor alpha (ERRalpha) has been implicated in the development of various human malignancies, including breast, prostate, ovary, and colon cancer. ERRalpha, bound to a co-activator protein (e.g., peroxisome proliferator receptor gamma co-activator-1alpha, PGC-1alpha), regulates cellular energy metabolism by activating transcription of genes involved in various metabolic processes, such as mitochondrial genesis, oxidative phosphorylation, and fatty acid oxidation. Accumulating evidence suggests that ERRalpha is a novel target for solid tumor therapy, conceivably through effects on the regulation of tumor cell energy metabolism associated with energy stress within solid tumor microenvironments. This report describes a novel steroidal antiestrogen (SR16388) that binds selectively to ERRalpha, but not to ERRbeta or ERRgamma, as determined using a time-resolved fluorescence resonance energy transfer assay. SR16388 potently inhibits ERRalpha's transcriptional activity in reporter gene assays, and prevents endogenous PGC-1alpha and ERRalpha from being recruited to the promoters or enhancers of target genes. Representative in vivo results show that SR16388 inhibited the growth of human prostate tumor xenografts in nude mice as a single agent at 30mg/kg given once daily and 100mg/kg given once weekly. In a combination study, SR16388 (10mg/kg, once daily) and paclitaxel (7.5mg/kg, twice weekly) inhibited the growth of prostate tumor xenografts in nude mice by 61% compared to untreated xenograft tumors. SR16388 also inhibited the proliferation of diverse human tumor cell lines after a 24-h exposure to the compound. SR16388 thus has utility both as an experimental antitumor agent and as a chemical probe of ERRalpha biology. Copyright 2010 Elsevier Inc. All rights reserved.

  7. Short-term exposure to a neuroactive steroid increases alpha4 GABA(A) receptor subunit levels in association with increased anxiety in the female rat.

    Science.gov (United States)

    Gulinello, M; Gong, Q H; Li, X; Smith, S S

    2001-08-10

    Previous work from this laboratory has demonstrated that withdrawal from the neuroactive steroid 3alpha,5alpha-THP (3alpha-hydroxy-5alpha-pregnan-20-one) after 3-week exposure to its parent compound, progesterone (P), increases anxiety and produces benzodiazepine (BDZ) insensitivity in female rats. These events were linked to upregulation of the alpha4 subunit of the GABA(A) receptor (GABAR) in the hippocampus [Brain Res. 507 (1998) 91; Nature 392 (1998) 926; J. Neurosci. 18 (1998) 5275]. The present study investigates the role of shorter term hormone treatment on alpha4 subunit levels as well as relevant behavioral and pharmacological end-points related to GABAR function. After 2-3 days of P exposure, two- to threefold increases in alpha4 protein levels were observed, which declined to control values after 5-6 days of hormone exposure. This effect was due to the GABA-modulatory metabolite of P, 3alpha,5alpha-THP. alpha4 upregulation was inversely correlated with BDZ potentiation of GABA-gated current, assessed using whole cell patch clamp techniques on acutely isolated hippocampal pyramidal cells. A near total BDZ insensitivity was observed by 2-3 days of hormone exposure in association with the maximal increase in alpha4 levels. Up-regulation of the alpha4 GABAR subunit was also reflected by an increase in anxiety in the elevated plus maze. A significant decrease in open arm entries was observed after 72-h exposure to P, an effect which recovered by 6 days of P treatment. As demonstrated in vitro, alpha4 upregulation also resulted in a relative insensitivity to the anxiolytic actions of BDZ. These results suggest that short-term exposure to 3alpha,5alpha-THP produces changes in GABAR subunit composition similar to those that occur after chronic exposure and withdrawal from the steroid.

  8. Growth hormone-dependent phosphorylation of tyrosine 333 and/or 338 of the growth hormone receptor

    DEFF Research Database (Denmark)

    VanderKuur, J A; Wang, X; Zhang, L

    1995-01-01

    Many signaling pathways initiated by ligands that activate receptor tyrosine kinases have been shown to involve the binding of SH2 domain-containing proteins to specific phosphorylated tyrosines in the receptor. Although the receptor for growth hormone (GH) does not contain intrinsic tyrosine...

  9. DEHP reduces thyroid hormones via interacting with hormone synthesis-related proteins, deiodinases, transthyretin, receptors, and hepatic enzymes in rats.

    Science.gov (United States)

    Liu, Changjiang; Zhao, Letian; Wei, Li; Li, Lianbing

    2015-08-01

    Di-(2-ethylhexyl) phthalate (DEHP) is used extensively in many personal care and consumer products, resulting in widespread nonoccupational human exposure through multiple routes and media. Limited studies suggest that exposure to DEHP may be associated with altered thyroid function, but detailed mechanisms are unclear. In order to elucidate potential mechanisms by which DEHP disturbs thyroid hormone homeostasis, Sprague-Dawley (SD) rats were dosed with DEHP by gavage at 0, 250, 500, and 750 mg/kg/day for 30 days and sacrificed within 24 h after the last dose. Gene expressions of thyroid hormone receptors, deiodinases, transthyretin, and hepatic enzymes were measured by RT-PCR; protein levels of transthyretin were also analyzed by Western blot. Results showed that DEHP caused histological changes in the thyroid and follicular epithelial cell hypertrophy and hyperplasia were observed. DEHP significantly reduced thyroid hormones (T3, T4) and thyrotropin releasing hormone (TRH) levels, whereas thyroid stimulating hormone (TSH) was not affected. After exposure to DEHP, biosynthesis of thyroid hormones was suppressed, and sodium iodide symporter (NIS) and thyroid peroxidase (TPO) levels were significantly reduced. Additionally, levels of deiodinases and transthyretin were also affected. TSH receptor (TSHr) level was downregulated, while TRH receptor (TRHr) level was upregulated. Metabolism of thyroid hormones was accelerated due to elevated gene expression of hepatic enzymes (UDPGTs and CYP2B1) by DEHP. Taken together, observed findings indicate that DEHP could reduce thyroid hormones through influencing biosynthesis, biotransformation, biotransport, receptor levels, and metabolism of thyroid hormones.

  10. Plant nuclear hormone receptors: a role for small molecules in protein-protein interactions.

    Science.gov (United States)

    Lumba, Shelley; Cutler, Sean; McCourt, Peter

    2010-01-01

    Plant hormones are a group of chemically diverse small molecules that direct processes ranging from growth and development to biotic and abiotic stress responses. Surprisingly, genome analyses suggest that classic animal nuclear hormone receptor homologs do not exist in plants. It now appears that plants have co-opted several protein families to perceive hormones within the nucleus. In one solution to the problem, the hormones auxin and jasmonate (JA) act as “molecular glue” that promotes protein-protein interactions between receptor F-boxes and downstream corepressor targets. In another solution, gibberellins (GAs) bind and elicit a conformational change in a novel soluble receptor family related to hormone-sensitive lipases. Abscisic acid (ABA), like GA, also acts through an allosteric mechanism involving a START-domain protein. The molecular identification of plant nuclear hormone receptors will allow comparisons with animal nuclear receptors and testing of fundamental questions about hormone function in plant development and evolution.

  11. Antagonism of Lateral Amygdala Alpha1-Adrenergic Receptors Facilitates Fear Conditioning and Long-Term Potentiation

    Science.gov (United States)

    Lazzaro, Stephanie C.; Hou, Mian; Cunha, Catarina; LeDoux, Joseph E.; Cain, Christopher K.

    2010-01-01

    Norepinephrine receptors have been studied in emotion, memory, and attention. However, the role of alpha1-adrenergic receptors in fear conditioning, a major model of emotional learning, is poorly understood. We examined the effect of terazosin, an alpha1-adrenergic receptor antagonist, on cued fear conditioning. Systemic or intra-lateral amygdala…

  12. Peroxisome Proliferator-Activated Receptor Alpha Target Genes

    Directory of Open Access Journals (Sweden)

    Maryam Rakhshandehroo

    2010-01-01

    Full Text Available The peroxisome proliferator-activated receptor alpha (PPARα is a ligand-activated transcription factor involved in the regulation of a variety of processes, ranging from inflammation and immunity to nutrient metabolism and energy homeostasis. PPARα serves as a molecular target for hypolipidemic fibrates drugs which bind the receptor with high affinity. Furthermore, PPARα binds and is activated by numerous fatty acids and fatty acid-derived compounds. PPARα governs biological processes by altering the expression of a large number of target genes. Accordingly, the specific role of PPARα is directly related to the biological function of its target genes. Here, we present an overview of the involvement of PPARα in lipid metabolism and other pathways through a detailed analysis of the different known or putative PPARα target genes. The emphasis is on gene regulation by PPARα in liver although many of the results likely apply to other organs and tissues as well.

  13. Peroxisome Proliferator-Activated Receptor Alpha Target Genes

    Science.gov (United States)

    Rakhshandehroo, Maryam; Knoch, Bianca; Müller, Michael; Kersten, Sander

    2010-01-01

    The peroxisome proliferator-activated receptor alpha (PPARα) is a ligand-activated transcription factor involved in the regulation of a variety of processes, ranging from inflammation and immunity to nutrient metabolism and energy homeostasis. PPARα serves as a molecular target for hypolipidemic fibrates drugs which bind the receptor with high affinity. Furthermore, PPARα binds and is activated by numerous fatty acids and fatty acid-derived compounds. PPARα governs biological processes by altering the expression of a large number of target genes. Accordingly, the specific role of PPARα is directly related to the biological function of its target genes. Here, we present an overview of the involvement of PPARα in lipid metabolism and other pathways through a detailed analysis of the different known or putative PPARα target genes. The emphasis is on gene regulation by PPARα in liver although many of the results likely apply to other organs and tissues as well. PMID:20936127

  14. Anorectic actions of prolactin-releasing peptide are mediated by corticotropin-releasing hormone receptors.

    Science.gov (United States)

    Lawrence, Catherine B; Liu, Yong-Ling; Stock, Michael J; Luckman, Simon M

    2004-01-01

    Prolactin-releasing peptide (PrRP) reduces food intake and body weight and modifies body temperature when administered centrally in rats, suggesting a role in energy homeostasis. However, the mediators of PrRP's actions are unknown. The present study, therefore, first examined the possible involvement of the anorectic neuropeptides corticotropin-releasing hormone (CRH) and the melanocortins (e.g., alpha-melanocyte-stimulating hormone) in PrRP's effects on food intake and core body temperature and, second, determined if PrRP affects energy expenditure by measuring oxygen consumption (Vo2). Intracerebroventricular injection of PrRP (4 nmol) to 24-h-fasted male Sprague-Dawley rats decreased food intake and modified body temperature. Blockade of central CRH receptors by intracerebroventricular coadministration of the CRH receptor antagonist astressin (20 microg) reversed the PrRP-induced reduction in feeding. However, astressin's effect on PrRP-induced changes in body temperature was complicated because the antagonist itself caused a slight rise in body temperature. In contrast, intracerebroventricular coadministration of the melanocortin receptor-3/4 antagonist SHU-9119 (0.1 nmol) had no effect on any of PrRP's actions. Finally, intracerebroventricular injection of PrRP (4 nmol) caused a significantly greater Vo2 over a 3-h test period compared with vehicle-treated rats. These results show that the anorectic actions of PrRP are mediated by central CRH receptors but not by melanocortin receptors-3/4 and that PrRP can modify Vo2.

  15. Growth hormone receptor expression and function in pituitary adenomas

    DEFF Research Database (Denmark)

    Clausen, Lene R; Kristiansen, Mikkel T; Rasmussen, Lars M

    2004-01-01

    OBJECTIVE AND DESIGN: Hypopituitarism, in particular GH deficiency, is prevalent in patients with clinically nonfunctioning pituitary adenomas (NFPAs) both before and after surgery. The factors regulating the growth of pituitary adenomas in general and residual tumour tissue in particular....... CONCLUSION: GH receptors are expressed in human pituitary adenoma cells but their functional role is uncertain. GH and IGF-I do not consistently influence the proliferation of cultured pituitary adenoma cells....... are not fully characterized, and the effect of GH and IGF-I on human pituitary cell proliferation has not previously been reported. In NFPA tissue from 14 patients we evaluated GH receptor (GHR) expression and signal transduction, and the effect of GH and IGF-I exposure on cell proliferation and hormone...

  16. The orphan nuclear hormone receptor ERRβ controls rod photoreceptor survival

    Science.gov (United States)

    Onishi, Akishi; Peng, Guang-Hua; Poth, Erin M.; Lee, Daniel A.; Chen, Jichao; Alexis, Uel; de Melo, Jimmy; Chen, Shiming; Blackshaw, Seth

    2010-01-01

    Mutation of rod photoreceptor-enriched transcription factors is a major cause of inherited blindness. We identified the orphan nuclear hormone receptor estrogen-related receptor β (ERRβ) as selectively expressed in rod photoreceptors. Overexpression of ERRβ induces expression of rod-specific genes in retinas of wild-type as well as Nrl−/− mice, which lack rod photoreceptors. Mutation of ERRβ results in dysfunction and degeneration of rods, whereas inverse agonists of ERRβ trigger rapid rod degeneration, which is rescued by constitutively active mutants of ERRβ. ERRβ coordinates expression of multiple genes that are rate-limiting regulators of ATP generation and consumption in photoreceptors. Furthermore, enhancing ERRβ activity rescues photoreceptor defects that result from loss of the photoreceptor-specific transcription factor Crx. Our findings demonstrate that ERRβ is a critical regulator of rod photoreceptor function and survival, and suggest that ERRβ agonists may be useful in the treatment of certain retinal dystrophies. PMID:20534447

  17. Neither bST nor Growth Hormone Releasing Factor Alter Expression of Thyroid Hormone Receptors in Liver and Mammary Tissues

    Science.gov (United States)

    Physiological effects of thyroid hormones are mediated primarily by binding of triiodothyronine, to specific nuclear receptors. It has been hypothesized that organ-specific changes in production of triiodothyronine from its prohormone, thyroxine, target the action of thyroid hormones to the mammary...

  18. Reproductive Hormones and Their Receptors May Affect Lung Cancer

    Directory of Open Access Journals (Sweden)

    Mengmeng Dou

    2017-11-01

    Full Text Available Background/Aims: In contrast to men, women have experienced a rapid increase in lung cancer mortality. Numerous studies have found that the sex differences in lung cancer are due to reproductive hormones. Experiments in female mice with and without ovariectomy were performed to explore the possible mechanism by which sex hormones (and their receptors influence lung cancer. Methods: Twenty-four female C57BL/6 mice aged 56-62 days were randomly divided into the ovariectomized group and the control group. In the ovariectomized group, the bilateral ovaries were removed via the dorsal approach, while the control group underwent a sham operation with bilateral ovarian fat resection at the same sites. After 3 weeks of recovery, Lewis lung cancer cells were transplanted into these mice by subcutaneous inoculation of a tumour cell suspension to establish the ovariectomized lung cancer model. Beginning on the 6th day after subcutaneous inoculation, mouse weight and transplanted tumour volume were measured every 3 days. After 3 weeks, all the mice were killed by cervical dislocation, and we measured the tumour weight. Mouse serum and tumour tissues were removed. Then, the serum levels of E2 (oestradiol and T (testosterone were detected by ELISA; the protein expression levels of AR (androgen receptor, ERα (oestrogen receptor α and ERβ (oestrogen receptor β were detected by Western Blot and IHC (immunohistochemistry; and the mRNA expression levels of AR, ERα and ERβ were detected by qRT-PCR (quantitative real-time polymerase chain reaction in the ovariectomized and control groups. Results: Compared with the control group, both mouse weight and transplanted tumour volume increased rapidly in the ovariectomized group, and the transplanted tumour weight was significantly heavier in the ovariectomized group (1.83±0.40 and 3.13±0.43, P<0.05. E2 and T serum levels decreased exponentially in the ovariectomized group, while the E2/T ratio increased compared

  19. Evolution of minimal specificity and promiscuity in steroid hormone receptors.

    Science.gov (United States)

    Eick, Geeta N; Colucci, Jennifer K; Harms, Michael J; Ortlund, Eric A; Thornton, Joseph W

    2012-01-01

    Most proteins are regulated by physical interactions with other molecules; some are highly specific, but others interact with many partners. Despite much speculation, we know little about how and why specificity/promiscuity evolves in natural proteins. It is widely assumed that specific proteins evolved from more promiscuous ancient forms and that most proteins' specificity has been tuned to an optimal state by selection. Here we use ancestral protein reconstruction to trace the evolutionary history of ligand recognition in the steroid hormone receptors (SRs), a family of hormone-regulated animal transcription factors. We resurrected the deepest ancestral proteins in the SR family and characterized the structure-activity relationships by which they distinguished among ligands. We found that that the most ancient split in SR evolution involved a discrete switch from an ancient receptor for aromatized estrogens--including xenobiotics--to a derived receptor that recognized non-aromatized progestagens and corticosteroids. The family's history, viewed in relation to the evolution of their ligands, suggests that SRs evolved according to a principle of minimal specificity: at each point in time, receptors evolved ligand recognition criteria that were just specific enough to parse the set of endogenous substances to which they were exposed. By studying the atomic structures of resurrected SR proteins, we found that their promiscuity evolved because the ancestral binding cavity was larger than the primary ligand and contained excess hydrogen bonding capacity, allowing adventitious recognition of larger molecules with additional functional groups. Our findings provide an historical explanation for the sensitivity of modern SRs to natural and synthetic ligands--including endocrine-disrupting drugs and pollutants--and show that knowledge of history can contribute to ligand prediction. They suggest that SR promiscuity may reflect the limited power of selection within real

  20. Evolution of Minimal Specificity and Promiscuity in Steroid Hormone Receptors

    Science.gov (United States)

    Eick, Geeta N.; Colucci, Jennifer K.; Harms, Michael J.; Ortlund, Eric A.; Thornton, Joseph W.

    2012-01-01

    Most proteins are regulated by physical interactions with other molecules; some are highly specific, but others interact with many partners. Despite much speculation, we know little about how and why specificity/promiscuity evolves in natural proteins. It is widely assumed that specific proteins evolved from more promiscuous ancient forms and that most proteins' specificity has been tuned to an optimal state by selection. Here we use ancestral protein reconstruction to trace the evolutionary history of ligand recognition in the steroid hormone receptors (SRs), a family of hormone-regulated animal transcription factors. We resurrected the deepest ancestral proteins in the SR family and characterized the structure-activity relationships by which they distinguished among ligands. We found that that the most ancient split in SR evolution involved a discrete switch from an ancient receptor for aromatized estrogens—including xenobiotics—to a derived receptor that recognized non-aromatized progestagens and corticosteroids. The family's history, viewed in relation to the evolution of their ligands, suggests that SRs evolved according to a principle of minimal specificity: at each point in time, receptors evolved ligand recognition criteria that were just specific enough to parse the set of endogenous substances to which they were exposed. By studying the atomic structures of resurrected SR proteins, we found that their promiscuity evolved because the ancestral binding cavity was larger than the primary ligand and contained excess hydrogen bonding capacity, allowing adventitious recognition of larger molecules with additional functional groups. Our findings provide an historical explanation for the sensitivity of modern SRs to natural and synthetic ligands—including endocrine-disrupting drugs and pollutants—and show that knowledge of history can contribute to ligand prediction. They suggest that SR promiscuity may reflect the limited power of selection within real

  1. Evolution of minimal specificity and promiscuity in steroid hormone receptors.

    Directory of Open Access Journals (Sweden)

    Geeta N Eick

    Full Text Available Most proteins are regulated by physical interactions with other molecules; some are highly specific, but others interact with many partners. Despite much speculation, we know little about how and why specificity/promiscuity evolves in natural proteins. It is widely assumed that specific proteins evolved from more promiscuous ancient forms and that most proteins' specificity has been tuned to an optimal state by selection. Here we use ancestral protein reconstruction to trace the evolutionary history of ligand recognition in the steroid hormone receptors (SRs, a family of hormone-regulated animal transcription factors. We resurrected the deepest ancestral proteins in the SR family and characterized the structure-activity relationships by which they distinguished among ligands. We found that that the most ancient split in SR evolution involved a discrete switch from an ancient receptor for aromatized estrogens--including xenobiotics--to a derived receptor that recognized non-aromatized progestagens and corticosteroids. The family's history, viewed in relation to the evolution of their ligands, suggests that SRs evolved according to a principle of minimal specificity: at each point in time, receptors evolved ligand recognition criteria that were just specific enough to parse the set of endogenous substances to which they were exposed. By studying the atomic structures of resurrected SR proteins, we found that their promiscuity evolved because the ancestral binding cavity was larger than the primary ligand and contained excess hydrogen bonding capacity, allowing adventitious recognition of larger molecules with additional functional groups. Our findings provide an historical explanation for the sensitivity of modern SRs to natural and synthetic ligands--including endocrine-disrupting drugs and pollutants--and show that knowledge of history can contribute to ligand prediction. They suggest that SR promiscuity may reflect the limited power of

  2. Immunohistochemical localization of progesterone receptor isoforms and estrogen receptor alpha in the chicken oviduct magnum during development.

    Science.gov (United States)

    González-Morán, María Genoveva

    2015-10-01

    In this work, the immunohistochemical expression of progesterone receptor (PR) isoforms and estrogen receptor alpha (ER-α), as well as the histomorphometric changes of the magnum region of the left oviduct from 8-day-old chicken embryos to one-month-old chickens were evaluated. Results indicate evident histological changes in the oviduct magnum during development mainly in the magnum's mucosa. Immunohistochemical analysis showed that the oviduct magnum from 8-day-old chicken embryos to one-day-old chickens did not present any PR isoform, but the oviduct magnum of one-week and one-month-old chickens expressed PR in the nuclei of all cell types. In epithelial cells, PR-B was the only isoform expressed; in muscle and serosa cells, PR-A isoform was the only isoform expressed; and stromal cells expressed both isoforms. The results also demonstrate positive ER-α immunostaining in the nuclei of different cells from embryonic life to later developmental stages of the oviduct magnum. Data indicate that the variations of ER-α or PR expression or dominance of either PR expression is differentially regulated depending on the cell type, the development of the oviduct, and in an age-specific manner. These variations in sex steroids hormone receptors are related with histological changes of the oviduct magnum through development. Copyright © 2015 Elsevier GmbH. All rights reserved.

  3. Distribution of the mRNAs encoding the thyrotropin-releasing hormone (TRH) precursor and three TRH receptors in the brain and pituitary of Xenopus laevis: Effect of background color adaptation on TRH and TRH receptor gene expression

    NARCIS (Netherlands)

    Bidaud, I.; Galas, L.; Bulant, M.; Jenks, B.G.; Ouwens, D.T.W.M.; Jegou, S.; Ladram, A.; Roubos, E.W.; Tonon, M.C.; Nicolas, P.; Vaudry, H.

    2004-01-01

    In amphibians, thyrotropin-releasing hormone (TRH) is a potent stimulator of et-melanotropin (alpha-MSH) secretion, so TRH plays a major role in the neuroendocrine regulation of skin-color adaptation. We have recently cloned a third type of TRH receptor in Xenopus laevis (xTRHR3) that has not yet

  4. Endorphins and the hypotensive response to stimulation of alpha-receptors in the brainstem by alpha-methylnoradrenaline

    NARCIS (Netherlands)

    Jong, Wybren de; Petty, M.A.

    1984-01-01

    Opioid peptide involvement in the fall in blood pressure resulting from stimulation of alpha-receptors in the brainstem has been investigated in the urethane-anaesthetised rat. Unilateral microinjection of alpha-methylnoradrenaline into the nucleus tractus solitarii (NTS) induced a doserelated fall

  5. Development and validation of fluorescent receptor assays based on the human recombinant estrogen receptor subtypes alpha and beta

    NARCIS (Netherlands)

    de boer, T; Otjens, D; Muntendam, A; Meulman, E; van Oostijen, M; Ensing, K

    2004-01-01

    This article describes the development and validation of two fluorescent receptor assays for the hRec-estrogen receptor subtypes alpha and beta. As a labelled ligand an autofluorescent phyto-estrogen (coumestrol) has been used. The estrogen receptor (ER) belongs to the nuclear receptor family, a

  6. Estrogen receptor alpha and risk for cognitive impairment in postmenopausal women

    DEFF Research Database (Denmark)

    Olsen, Line; Rasmussen, Henrik B; Hansen, Thomas

    2006-01-01

    The estrogen receptor alpha (ESR1) gene has been implicated in the process of cognitive impairment in elderly women. In a paired case-control study, we tested whether two ESR1 gene polymorphisms (the XbaI and PvuII sites) are risk factors for cognitive impairment as measured by the six......-item Orientation-Memory-Concentration test in postmenopausal Danish women. Hormone replacement therapy, age and executive cognitive ability were examined as covariates for ESR1 gene effects on cognitive impairment. The XbaI polymorphism showed a marginal effect on cognitive abilities (P=0.054) when adjusted...... cognitive ability. These data support that the ESR1 gene variants affect cognitive functioning in postmenopausal women....

  7. The thyroid hormone receptors modulate the skin response to retinoids.

    Directory of Open Access Journals (Sweden)

    Laura García-Serrano

    Full Text Available Retinoids play an important role in skin homeostasis and when administered topically cause skin hyperplasia, abnormal epidermal differentiation and inflammation. Thyroidal status in humans also influences skin morphology and function and we have recently shown that the thyroid hormone receptors (TRs are required for a normal proliferative response to 12-O-tetradecanolyphorbol-13-acetate (TPA in mice.We have compared the epidermal response of mice lacking the thyroid hormone receptor binding isoforms TRα1 and TRβ to retinoids and TPA. Reduced hyperplasia and a decreased number of proliferating cells in the basal layer in response to 9-cis-RA and TPA were found in the epidermis of TR-deficient mice. Nuclear levels of proteins important for cell proliferation were altered, and expression of keratins 5 and 6 was also reduced, concomitantly with the decreased number of epidermal cell layers. In control mice the retinoid (but not TPA induced parakeratosis and diminished expression of keratin 10 and loricrin, markers of early and terminal epidermal differentiation, respectively. This reduction was more accentuated in the TR deficient animals, whereas they did not present parakeratosis. Therefore, TRs modulate both the proliferative response to retinoids and their inhibitory effects on skin differentiation. Reduced proliferation, which was reversed upon thyroxine treatment, was also found in hypothyroid mice, demonstrating that thyroid hormone binding to TRs is required for the normal response to retinoids. In addition, the mRNA levels of the pro-inflammatory cytokines TNFα and IL-6 and the chemotactic proteins S1008A and S1008B were significantly elevated in the skin of TR knock-out mice after TPA or 9-cis-RA treatment and immune cell infiltration was also enhanced.Since retinoids are commonly used for the treatment of skin disorders, these results demonstrating that TRs regulate skin proliferation, differentiation and inflammation in response to

  8. Nuclear Import and Export of the Thyroid Hormone Receptor.

    Science.gov (United States)

    Zhang, Jibo; Roggero, Vincent R; Allison, Lizabeth A

    2018-01-01

    The thyroid hormone receptors, TRα1 and TRβ1, are members of the nuclear receptor superfamily that forms one of the most abundant classes of transcription factors in multicellular organisms. Although primarily localized to the nucleus, TRα1 and TRβ1 shuttle rapidly between the nucleus and cytoplasm. The fine balance between nuclear import and export of TRs has emerged as a critical control point for modulating thyroid hormone-responsive gene expression. Mutagenesis studies have defined two nuclear localization signal (NLS) motifs that direct nuclear import of TRα1: NLS-1 in the hinge domain and NLS-2 in the N-terminal A/B domain. Three nuclear export signal (NES) motifs reside in the ligand-binding domain. A combined approach of shRNA-mediated knockdown and coimmunoprecipitation assays revealed that nuclear entry of TRα1 is facilitated by importin 7, likely through interactions with NLS-2, and importin β1 and the adapter importin α1 interacting with both NLS-1 and NLS-2. Interestingly, TRβ1 lacks NLS-2 and nuclear import depends solely on the importin α1/β1 heterodimer. Heterokaryon and fluorescence recovery after photobleaching shuttling assays identified multiple exportins that play a role in nuclear export of TRα1, including CRM1 (exportin 1), and exportins 4, 5, and 7. Even single amino acid changes in TRs dramatically alter their intracellular distribution patterns. We conclude that mutations within NLS and NES motifs affect nuclear shuttling activity, and propose that TR mislocalization contributes to the development of some types of cancer and Resistance to Thyroid Hormone syndrome. © 2018 Elsevier Inc. All rights reserved.

  9. The Neuroendocrine Functions of the Parathyroid Hormone 2 Receptor

    Directory of Open Access Journals (Sweden)

    Arpad eDobolyi

    2012-10-01

    Full Text Available The G-protein coupled parathyroid hormone 2 receptor (PTH2R is concentrated in endocrine and limbic regions in the forebrain. Its endogenous ligand,tuberoinfundibular peptide of 39 residues (TIP39, is synthesized in only 2 brain regions, within the posterior thalamus and the lateral pons. TIP39-expressing neurons have a widespread projection pattern, which matches the PTH2R distribution in the brain. Neuroendocrine centers including the preoptic area, the periventricular, paraventricular, and arcuate nuclei contain the highest density of PTH2R-positive networks. The administration of TIP39 and an antagonist of the PTH2R as well as the investigation of mice that lack functional TIP39 and PTH2R revealed the involvement of the PTH2R in a variety of neural and neuroendocrine functions. TIP39 acting via the PTH2R modulates several aspects of the stress response. It evokes corticosterone release by activating corticotropin-releasing hormone-containing neurons in the hypothalamic paraventricular nucleus. Block of TIP39 signaling elevates the anxiety state of animals and their fear response, and increases stress-induced analgesia. TIP39 has also been suggested to affect the release of additional pituitary hormones including arginine vasopressin and growth hormone. A role of the TIP39-PTH2R system in thermoregulation was also identified. TIP39 may play a role in maintaining body temperature in a cold environment via descending excitatory pathways from the preoptic area. Anatomical and functional studies also implicated the TIP39-PTH2R system in nociceptive information processing. Finally, TIP39 induced in postpartum dams may play a role in the release of prolactin during lactation. Potential mechanisms leading to the activation of TIP39 neurons and how they influence the neuroendocrine system are also described. The unique TIP39-PTH2R neuromodulator system provides the possibility for developing drugs with a novel mechanism of action to control

  10. Palbociclib in Hormone-Receptor-Positive Advanced Breast Cancer.

    Science.gov (United States)

    Turner, Nicholas C; Ro, Jungsil; André, Fabrice; Loi, Sherene; Verma, Sunil; Iwata, Hiroji; Harbeck, Nadia; Loibl, Sibylle; Huang Bartlett, Cynthia; Zhang, Ke; Giorgetti, Carla; Randolph, Sophia; Koehler, Maria; Cristofanilli, Massimo

    2015-07-16

    Growth of hormone-receptor-positive breast cancer is dependent on cyclin-dependent kinases 4 and 6 (CDK4 and CDK6), which promote progression from the G1 phase to the S phase of the cell cycle. We assessed the efficacy of palbociclib (an inhibitor of CDK4 and CDK6) and fulvestrant in advanced breast cancer. This phase 3 study involved 521 patients with advanced hormone-receptor-positive, human epidermal growth factor receptor 2-negative breast cancer that had relapsed or progressed during prior endocrine therapy. We randomly assigned patients in a 2:1 ratio to receive palbociclib and fulvestrant or placebo and fulvestrant. Premenopausal or perimenopausal women also received goserelin. The primary end point was investigator-assessed progression-free survival. Secondary end points included overall survival, objective response, rate of clinical benefit, patient-reported outcomes, and safety. A preplanned interim analysis was performed by an independent data and safety monitoring committee after 195 events of disease progression or death had occurred. The median progression-free survival was 9.2 months (95% confidence interval [CI], 7.5 to not estimable) with palbociclib-fulvestrant and 3.8 months (95% CI, 3.5 to 5.5) with placebo-fulvestrant (hazard ratio for disease progression or death, 0.42; 95% CI, 0.32 to 0.56; Ppalbociclib-fulvestrant group were neutropenia (62.0%, vs. 0.6% in the placebo-fulvestrant group), leukopenia (25.2% vs. 0.6%), anemia (2.6% vs. 1.7%), thrombocytopenia (2.3% vs. 0%), and fatigue (2.0% vs. 1.2%). Febrile neutropenia was reported in 0.6% of palbociclib-treated patients and 0.6% of placebo-treated patients. The rate of discontinuation due to adverse events was 2.6% with palbociclib and 1.7% with placebo. Among patients with hormone-receptor-positive metastatic breast cancer who had progression of disease during prior endocrine therapy, palbociclib combined with fulvestrant resulted in longer progression-free survival than fulvestrant alone

  11. Biological response to hormonal manipulation in oestrogen receptor positive ductal carcinoma in situ of the breast

    National Research Council Canada - National Science Library

    Boland, G P; McKeown, A; Chan, K C; Prasad, R; Knox, W F; Bundred, N J

    2003-01-01

    ...) to reduce local recurrence, despite 50% of lesions being oestrogen receptor (OR) negative. We have investigated the response to hormone manipulation in DCIS by studying changes in epithelial proliferation and progesterone receptor...

  12. Persistent signaling by thyrotropin-releasing hormone receptors correlates with G-protein and receptor levels

    Science.gov (United States)

    Boutin, Alisa; Allen, Michael D.; Neumann, Susanne; Gershengorn, Marvin C.

    2012-01-01

    G-protein-coupled receptors with dissociable agonists for thyrotropin, parathyroid hormone, and sphingosine-1-phosphate were found to signal persistently hours after agonist withdrawal. Here we show that mouse thyrotropin-releasing hormone (TRH) receptors, subtypes 2 and 1(TRH-R2 and TRH-R1), can signal persistently in HEK-EM293 cells under appropriate conditions, but TRH-R2 exhibits higher persistent signaling activity. Both receptors couple primarily to Gαq/11. To gain insight into the mechanism of persistent signaling, we compared proximal steps of inositolmonophosphate (IP1) signaling by TRH-Rs. Persistent signaling was not caused by slower dissociation of TRH from TRH-R2 (t1/2=77±8.1 min) compared with TRH-R1 (t1/2=82±12 min) and was independent of internalization, as inhibition of internalization did not affect persistent signaling (115% of control), but required continuously activated receptors, as an inverse agonist decreased persistent signaling by 60%. Gαq/11 knockdown decreased persistent signaling by TRH-R2 by 82%, and overexpression of Gαq/11 induced persistent signaling in cells expressing TRH-R1. Lastly, persistent signaling was induced in cells expressing high levels of TRH-R1. We suggest that persistent signaling by TRHRs is exhibited when sufficient levels of agonist/receptor/G-protein complexes are established and maintained and that TRH-R2 forms and maintains these complexes more efficiently than TRH-R1.—Boutin, A., Allen, M. D., Neumann, S., Gershengorn, M. C. Persistent signaling by thyrotropin-releasing hormone receptors correlates with G-protein and receptor levels. PMID:22593547

  13. GROWTH HORMONE-, ALPHA-SUBUNIT AND THYROTROPIN-COSECRETING PITUITARY-ADENOMA IN FAMILIAL SETTING OF PITUITARY-TUMOR

    NARCIS (Netherlands)

    LINKS, TP; MONKELBAAN, JF; DULLAART, RPF; VANHAEFTEN, TW

    1993-01-01

    A patient with acromegaly and hyperthyroidism due to a growth hormone-, thyrotrophin- and alpha-subunit-secreting pituitary adenoma is described. His deceased father had suffered from a pituitary tumour, and was likely to have had acromegaly as well. Plasma growth hormone and insulin-like growth

  14. Sertoli cell specific knockdown of RAR-related orphan receptor (ROR) alpha at puberty reduces sperm count in rats.

    Science.gov (United States)

    Mandal, Kamal; Sarkar, Rajesh K; Sen Sharma, Souvik; Jain, Ayushi; Majumdar, Subeer S

    2018-01-30

    Globally, there is an alarming decline in sperm count. Very often hormonal supplementation fails to restore normal sperm count. Sertoli cells (Sc) present within seminiferous tubules provide appropriate niche and factors required for the differentiation of germ cells (Gc) into mature sperm (spermatogenesis). Functionally compromised Sc may be one of the reasons for failure of hormones to facilitate normal spermatogenesis. Although role of secretory proteins and signaling molecules of Sc has been studied well, role of transcription factors regulating sperm count has not been addressed appropriately. Retinoic acid receptor-related orphan receptor (ROR)-alpha is one of such transcription factors reported in testis but its role in testicular function is not yet known. In a separate study, we found abundant ROR-alpha binding sites on promoter regions of several genes upregulated in pubertal rat Sc as compared to infant Sc. Immunostaining studies also revealed presence of ROR alpha in nucleus of pubertal Sc. We generated a transgenic knockdown rat model expressing shRNA targeted to ROR-alpha under Sc specific promoter, which is transcriptionally active only at and after puberty. ROR-alpha knockdown animals were found to have abnormal association of Sc and Gc, including Gc sloughing and restricted release of sperm. The knockdown animals displayed compromised spermatogenesis leading to significant reduction in sperm count. This is the first report describing the Sc specific role of ROR-alpha in maintaining quantitatively normal sperm output. Identification of various such molecules can generate avenues to limit or reverse an alarmingly declining sperm count witnessed globally in men. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Effects of Steroidal Antiandrogen or 5-alpha-reductase Inhibitor on Prostate Tissue Hormone Content.

    Science.gov (United States)

    Shibata, Yasuhiro; Arai, Seiji; Miyazawa, Yoshiyuki; Shuto, Takahiro; Nomura, Masashi; Sekine, Yoshitaka; Koike, Hidekazu; Matsui, Hiroshi; Ito, Kazuto; Suzuki, Kazuhiro

    2017-05-01

    The effects of a steroidal antiandrogen (AA) and 5-alpha-reductase inhibitor (5ARI) on prostate tissue hormone content and metabolism are not fully elucidated. The objective of this study is to investigate the hormone content and metabolism of the prostate tissues of patients treated with AA or 5ARI using the ultra-sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Thirty-nine patients with benign prostatic hyperplasia (BPH) undergoing transurethral surgery were included. Serum and prostate tissue hormone and prostate tissue hormone metabolism analyses were performed using LC-MS/MS after 1 month of treatment with chlormadinone acetate (CMA; steroidal AA, 50 mg/day) or dutasteride (DUTA; dual 5ARI, 0.5 mg/day). Serum testosterone (T), dihydrotestosterone (DHT), and adrenal androgen levels were lower in the CMA group than the control group. Prostate tissue T and DHT levels were also lower in the CMA group than the control group. In the DUTA group, only serum and prostate DHT concentrations were reduced compared to the control group; in contrast, those of other hormones, especially T and 4-androstene-3,17-dione in the prostate tissue, showed marked elevations up to 70.4- and 11.4-fold normal levels, respectively. Moreover, the hormone metabolism assay confirmed that the conversion of T to DHT was significantly suppressed while that of T to 4-androstene-3,17-dione was significantly accelerated in the prostate tissue of DUTA-treated patients. Although treatment with AA and 5ARI show similar clinical outcomes, their effect on tissue hormone content and metabolism varied greatly. Prostate 77: 672-680, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  16. Unique presynaptic alpha 2-receptor selectivity and specificity of the antihypertensive agent moxonidine.

    Science.gov (United States)

    Armah, B I

    1988-10-01

    The characteristics of the alpha-receptor activating property of the new antihypertensive agent moxonidine (4-chloro-N-(4, 5-dihydro-1H-imidazol-2-yl)-6-methyl-2-methyl-5-pyrimidinamine, BDF 5895) was studied using peripheral vasculature and brain membranes of various animals. Moxonidine exerted a full agonist effect in elevating diastolic blood pressure in the pithed rat. Activation of postsynaptic alpha 1- and alpha 2-receptors contribute to the vasoconstrictory effect in rats. In the vasculature of the rabbit, moxonidine was a full agonist at presynaptic alpha 2-receptors in inhibiting transmitter release induced by electrical stimulation of pulmonary artery strips. At postsynaptic sites, exogenously applied moxonidine was a full agonist at alpha 1-receptors in the isolated aorta, pulmonary artery and vena cava of the rabbit. Selectivity for alpha 2-receptors in the pulmonary artery was 106-fold. In rat brain membranes, moxonidine showed 288-fold greater selectivity for alpha 2-receptors, when the displacement of [3H]-rauwolscine was compared with the displacement of [3H]-prazosin. On the whole, clonidine exhibited greater potency than moxonidine on both alpha-receptor subtypes, but moxonidine consistently showed greater alpha 2-receptor selectivity than clonidine. In the guinea pig myocardium, moxonidine caused neither bradycardia nor tachycardia in the isolated right atrium and produced a negligible positive inotropic effect at 100 mumol/l in the isolated papillary muscle.

  17. SENESCENCE-ASSOCIATED DECLINE IN HEPATIC PEROXISOMAL ENZYME ACTIVITIES CORRESPONDS WITH DIMINISHED LEVELS OF RETINOID X RECEPTOR ALPHA, BUT NOT PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR ALPHA1

    Science.gov (United States)

    AbstractAging is associated with alterations in hepatic peroxisomal metabolism and susceptibility to hepatocarcinogenecity produced by agonists of peroxisome proliferator-activated receptor alpha (PPARa). Mechanisms involved in these effects are not well understood. Howev...

  18. The c-erb-A protein is a high-affinity receptor for thyroid hormone

    DEFF Research Database (Denmark)

    Sap, J; Muñoz, A; Damm, K

    1987-01-01

    Hormone binding and localization of the c-erb-A protein suggest that it is a receptor for thyroid hormone, a nuclear protein that binds to DNA and activates transcription. In contrast, the product of the viral oncogene v-erb-A is defective in binding the hormone but is still located in the nucleus....

  19. Avian melanocortin system: alpha-MSH may act as an autocrine/paracrine hormone: a minireview.

    Science.gov (United States)

    Takeuchi, Sakae; Takahashi, Sumio; Okimoto, Ronald; Schioth, Helgi B; Boswell, Timothy

    2003-06-01

    The interest in the physiological role of alpha-MSH in birds has been limited because they lack the intermediate lobe of the pituitary, the main source of circulating alpha-MSH in most vertebrates. Recent studies have improved our understanding of the avian melanocortin system. We have cloned and characterized all five MC-R subtypes, POMC, and AGRP in chicken. Analyses of the tissue distribution of expression of these genes revealed widespread expression throughout the body, corresponding to the situation in mammals in which alpha-MSH exerts a multiplicity of effects in different tissues by acting as a local mediator. We showed that the extended black locus controlling feather pigmentation in the chicken encodes MC1-R. Moreover, black chickens carrying the dominant allele, the extended black, express the MC1-R with ligand-independent activity as the somber-3J black mice. alpha-MSH and AGRP were expressed in the infundibular nucleus of POMC and NPY neurons, respectively, in the brain of Japanese quail. Furthermore, fasting stimulated AGRP expression and lowered POMC expression. These data indicate that at least two of the major melanocortin systems reported in mammals, that is, regulation of pigmentation and energy homeostasis, was developed in a common ancestor to chicken and mammals at least 300 million years ago. Furthermore, alpha-MSH peptide was identified in developing chicken eye, suggesting a possible involvement of alpha-MSH in regulation of ocular development. Collectively, the data reviewed here indicate that alpha-MSH is produced locally and acts as an autocrine/paracrine hormone in birds.

  20. Unsaturated fatty acids prevent desensitization of the human growth hormone secretagogue receptor by blocking its internalization

    NARCIS (Netherlands)

    P.J.D. Delhanty (Patric); A. Kerkwijk (Anke); M. Huisman (Martijn); B. van de Zande (Bedette); M. Verhoef-Post (Miriam); C. Gauna (Carlotta); L.J. Hofland (Leo); A.P.N. Themmen (Axel); A-J. van der Lely (Aart-Jan)

    2010-01-01

    textabstractThe composition of the plasma membrane affects the responsiveness of cells to metabolically important hormones such as insulin and vasoactive intestinal peptide. Ghrelin is a metabolically regulated hormone that activates the G protein-coupled receptor GH secretagogue receptor type 1a

  1. The SOCS2 Ubiquitin Ligase Complex Regulates Growth Hormone Receptor Levels

    DEFF Research Database (Denmark)

    Vesterlund, Mattias; Zadjali, Fahad; Persson, Torbjörn

    2011-01-01

    Growth Hormone is essential for the regulation of growth and the homeostatic control of intermediary metabolism. GH actions are mediated by the Growth Hormone Receptor; a member of the cytokine receptor super family that signals chiefly through the JAK2/STAT5 pathway. Target tissue responsiveness...

  2. Ethnic and racial differences in prostate stromal estrogen receptor alpha.

    Science.gov (United States)

    Haqq, Christopher; Li, Rile; Khodabakhsh, Daniel; Frolov, Anna; Ginzinger, David; Thompson, Timothy; Wheeler, Thomas; Carroll, Peter; Ayala, Gustavo

    2005-10-01

    Prostate cancer incidence and mortality rates vary widely among individuals of different ethnic/racial groups. We identified a relationship between a subset of genes and race/ethnicity using gene expression profiling. Estrogen receptor alpha (ERalpha) was selected for confirmation due to its plausible biological role in cancer susceptibility. Quantitative polymerase chain reaction (Q-PCR) was used to verify gene expression results. Protein levels of ERalpha were determined by quantitative immunohistochemistry in a large-scale tissue microarray study (n = 183). ERalpha was significantly higher in stroma of Hispanic and Asian men than in Caucasian (P racial/ethnic background. Understanding the molecular basis for these differences may form the basis for prostate cancer prevention strategies with widespread public health impact. Copyright 2005 Wiley-Liss, Inc.

  3. Activity of L-alpha-amino acids at the promiscuous goldfish odorant receptor 5.24

    DEFF Research Database (Denmark)

    Christiansen, Bolette; Wellendorph, Petrine; Bräuner-Osborne, Hans

    2006-01-01

    The goldfish odorant receptor 5.24 is a member of family C of G protein-coupled receptors and is closely related to the human receptor GPRC6A. Receptor 5.24 has previously been shown to have binding affinity for L-alpha-amino acids, especially the basic amino acids arginine and lysine. Here we re...

  4. Molecular cloning, genomic organization, and developmental regulation of a novel receptor from Drosophila melanogaster structurally related to members of the thyroid-stimulating hormone, follicle-stimulating hormone, luteinizing hormone/choriogonadotropin receptor family from mammals

    DEFF Research Database (Denmark)

    Hauser, F; Nothacker, H P; Grimmelikhuijzen, C J

    1997-01-01

    ); follicle-stimulating hormone (FSH); luteinizing hormone/choriogonadotropin (LH/CG)) receptor family from mammals. This homology includes a very large, extracellular N terminus (20% sequence identity with rat TSH, 19% with rat FSH, and 20% with the rat LH/CG receptor) and a seven-transmembrane region (53...

  5. Surface expression of only gamma delta and/or alpha beta T cell receptor heterodimers by cells with four (alpha, beta, gamma, delta) functional receptor chains

    NARCIS (Netherlands)

    Saito, T.; Hochstenbach, F.; Marusic-Galesic, S.; Kruisbeek, A. M.; BRENNER, M.; GERMAIN, R. N.

    1988-01-01

    Surface expression of TCR dimers by cells synthesizing three or four distinct types of receptor chains was analyzed. Cells containing intact gamma, alpha, and beta chains had only gamma delta dimers on the cell surface. In human PEER cells, addition of a functional alpha chain led to the loss of

  6. On the Molecular Pharmacology of the Melanocortin-4 Receptor

    NARCIS (Netherlands)

    Nijenhuis, Wouter Albertus Johannes

    2003-01-01

    Melanocortin hormones, like alpha-MSH and ACTH (melanocyte stimulating hormone and adrenocorticotropic hormone), regulate several biological processes, including bodyweight homeostasis, neuropathic pain and nerve regeneration after nerve damage. Five melanocortin receptor subtypes have been cloned,

  7. Melanoma Therapy with Rhenium-Cyclized Alpha Melanocyte Stimulating Hormone Peptide Analogs

    Energy Technology Data Exchange (ETDEWEB)

    Thomas P Quinn

    2005-11-22

    Malignant melanoma is the 6th most commonly diagnosed cancer with increasing incidence in the United States. It is estimated that 54,200 cases of malignant melanoma will be newly diagnosed and 7,600 cases of death will occur in the United States in the year 2003 (1). At the present time, more than 1.3% of Americans will develop malignant melanoma during their lifetime (2). The average survival for patients with metastatic melanoma is about 6-9 months (3). Moreover, metastatic melanoma deposits are resistant to conventional chemotherapy and external beam radiation therapy (3). Systematic chemotherapy is the primary therapeutic approach to treat patients with metastatic melanoma. Dacarbazine is the only single chemotherapy agent approved by FDA for metastatic melanoma treatment (5). However, the response rate to Dacarbazine is only approximately 20% (6). Therefore, there is a great need to develop novel treatment approaches for metastatic melanoma. The global goal of this research program is the rational design, characterization and validation of melanoma imaging and therapeutic radiopharmaceuticals. Significant progress has been made in the design and characterization of metal-cyclized radiolabeled alpha-melanocyte stimulating hormone peptides. Therapy studies with {sup 188}Re-CCMSH demonstrated the therapeutic efficacy of the receptor-targeted treatment in murine and human melanoma bearing mice (previous progress report). Dosimetry calculations, based on biodistribution data, indicated that a significant dose was delivered to the tumor. However, {sup 188}Re is a very energetic beta-particle emitter. The longer-range beta-particles theoretically would be better for larger tumors. In the treatment of melanoma, the larger primary tumor is usually surgically removed leaving metastatic disease as the focus of targeted radiotherapy. Isotopes with lower beta-energies and/or shorter particle lengths should be better suited for targeting metastases. The {sup 177}Lu

  8. Technetium-99m-labeled Arg-Gly-Asp-conjugated alpha-melanocyte stimulating hormone hybrid peptides for human melanoma imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yang Jianquan; Guo Haixun [College of Pharmacy, University of New Mexico, Albuquerque, NM 87131 (United States); Miao Yubin, E-mail: ymiao@salud.unm.ed [College of Pharmacy, University of New Mexico, Albuquerque, NM 87131 (United States); Cancer Research and Treatment Center, University of New Mexico, Albuquerque, NM 87131 (United States); Department of Dermatology, University of New Mexico, Albuquerque, NM 87131 (United States)

    2010-11-15

    Introduction: The purpose of this study was to examine whether {sup 99m}Tc-labeled Arg-Gly-Asp (RGD)-conjugated alpha-melanocyte stimulating hormone ({alpha}-MSH) hybrid peptide targeting both melanocortin-1 (MC1) and {alpha}{sub v{beta}3} integrin receptors was superior in melanoma targeting to {sup 99m}Tc-labeled {alpha}-MSH or RGD peptide targeting only the MC1 or {alpha}{sub v{beta}3} integrin receptor. Methods: RGD-Lys-(Arg{sup 11})CCMSH, RAD-Lys-(Arg{sup 11})CCMSH and RGD-Lys-(Arg{sup 11})CCMSHscramble were designed to target both MC1 and {alpha}{sub v{beta}3} integrin receptors, MC1 receptor only and {alpha}{sub v{beta}3} integrin receptor only, respectively. The MC1 or {alpha}{sub v{beta}3} integrin receptor binding affinities of three peptides were determined in M21 human melanoma cells. The melanoma targeting properties of {sup 99m}Tc-labeled RGD-Lys-(Arg{sup 11})CCMSH, RAD-Lys-(Arg{sup 11})CCMSH and RGD-Lys-(Arg{sup 11})CCMSHscramble were determined in M21 human melanoma-xenografted nude mice. Meanwhile, the melanoma uptake of {sup 99m}Tc-RGD-Lys-(Arg{sup 11})CCMSH was blocked with various non-radiolabeled peptides in M21 melanoma xenografts. Results: RGD-Lys-(Arg{sup 11})CCMSH displayed 2.0 and 403 nM binding affinities to both MC1 and {alpha}{sub v{beta}3} integrin receptors, whereas RAD-Lys-(Arg{sup 11})CCMSH or RGD-Lys-(Arg{sup 11})CCMSHscramble lost their {alpha}{sub v{beta}3} integrin receptor binding affinity by greater than 248-fold or MC1 receptor binding affinity by more than 100-fold, respectively. The melanoma uptake of {sup 99m}Tc-RGD-Lys-(Arg{sup 11})CCMSH was 2.49 and 2.24 times (P < .05) the melanoma uptakes of {sup 99m}Tc-RAD-Lys-(Arg{sup 11})CCMSH and {sup 99m}Tc-RGD-Lys-(Arg{sup 11})CCMSHscramble at 2 h post-injection, respectively. Either RGD or (Arg{sup 11})CCMSH peptide co-injection could block 42% and 57% of the tumor uptake of {sup 99m}Tc-RGD-Lys-(Arg{sup 11})CCMSH, whereas the coinjection of RGD+(Arg{sup 11})CCMSH peptide mixture

  9. Cancer care Ontario guideline recommendations for hormone receptor testing in breast cancer.

    Science.gov (United States)

    Nofech-Mozes, S; Vella, E T; Dhesy-Thind, S; Hanna, W M

    2012-12-01

    Hormone receptor testing (oestrogen and progesterone) in breast cancer at the time of primary diagnosis is used to guide treatment decisions. Accurate and standardised testing methods are critical to ensure the proper classification of the patient's hormone receptor status. Recommendations were developed to improve the quality and accuracy of hormone receptor testing based on a systematic review conducted jointly by the American Society of Clinical Oncology/College of American Pathologists and Cancer Care Ontario's Program in Evidence-Based Care. Evidence-based recommendations were formulated to set standards for optimising immunohistochemistry in assessing hormone receptor status, as well as assuring quality and proficiency between and within laboratories. A formal external review was conducted to validate the relevance of these recommendations. It is anticipated that widespread adoption of these guidelines will further improve the accuracy of hormone receptor testing in Canada. Copyright © 2012 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  10. Alpha-receptor blockade improves muscle perfusion and glucose uptake in heart failure.

    NARCIS (Netherlands)

    Gomes, M.E.R.; Mulder, A.; Bellersen, L.; Verheugt, F.W.A.; Smits, P.; Tack, C.J.J.

    2010-01-01

    AIMS: Alpha-adrenergic receptor-mediated vasoconstriction might underlie the insulin resistance seen in conditions associated with increased sympathetic tone, like chronic heart failure (CHF). Alpha-adrenergic receptor blockade by phentolamine could improve forearm blood flow (FBF) and forearm

  11. Gene specific actions of thyroid hormone receptor subtypes.

    Directory of Open Access Journals (Sweden)

    Jean Z Lin

    Full Text Available There are two homologous thyroid hormone (TH receptors (TRs α and β, which are members of the nuclear hormone receptor (NR family. While TRs regulate different processes in vivo and other highly related NRs regulate distinct gene sets, initial studies of TR action revealed near complete overlaps in their actions at the level of individual genes. Here, we assessed the extent that TRα and TRβ differ in target gene regulation by comparing effects of equal levels of stably expressed exogenous TRs +/- T(3 in two cell backgrounds (HepG2 and HeLa. We find that hundreds of genes respond to T(3 or to unliganded TRs in both cell types, but were not able to detect verifiable examples of completely TR subtype-specific gene regulation. TR actions are, however, far from identical and we detect TR subtype-specific effects on global T(3 response kinetics in HepG2 cells and many examples of TR subtype specificity at the level of individual genes, including effects on magnitude of response to TR +/- T(3, TR regulation patterns and T(3 dose response. Cycloheximide (CHX treatment confirms that at least some differential effects involve verifiable direct TR target genes. TR subtype/gene-specific effects emerge in the context of widespread variation in target gene response and we suggest that gene-selective effects on mechanism of TR action highlight differences in TR subtype function that emerge in the environment of specific genes. We propose that differential TR actions could influence physiologic and pharmacologic responses to THs and selective TR modulators (STRMs.

  12. Signalling, cycling and desensitisation of gonadotrophin-releasing hormone receptors.

    Science.gov (United States)

    McArdle, Craig A; Franklin, J; Green, L; Hislop, J N

    2002-04-01

    down-regulation of inositol (1,4,5) trisphosphate receptors and desensitisation of Ca(2+) mobilisation in pituitary cells. The atypical resistance of the GnRH-R to desensitisation may underlie its atypical efficiency at provoking this downstream adaptive response. GnRH-Rs are also expressed in several extrapituitary sites, and these may mediate direct inhibition of proliferation of hormone-dependent cancer cells. Infection with type I GnRH-R-expressing adenovirus facilitated expression of high-affinity, PLC-coupled GnRH-R in mammary and prostate cancer cells, and these mediated pronounced antiproliferative effects of receptor agonists. No such effect was seen in cells transfected with a type II GnRH-R, implying that it is mediated most efficiently by a non-desensitising receptor. Thus it appears that the mammalian GnRH-Rs have undergone a period of rapidly accelerated molecular evolution that is of functional relevance to GnRH-Rs in pituitary and extrapituitary sites.

  13. Solubilization of a guanyl nucleotide-sensitive alpha/sub 1/ adrenergic receptor from liver membranes

    Energy Technology Data Exchange (ETDEWEB)

    Harris, S.I.; Moss, J.

    1987-05-01

    Rat liver membranes incubated with norepinephrine before solubilization with digitonin yielded a soluble hormone-receptor complex from which the release of tightly bound norepinephrine was facilitated by guanyl nucleotides. Binding of the alpha/sub 1/-adrenergic receptor antagonist, (/sup 3/H)-prazosin, to the soluble preparation was utilized as a gauge of guanyl nucleotide-induced release of receptor-bound agonist. The following potency series was obtained with regard to the ability of guanyl nucleotides to facilitate (/sup 3/H)-prazosin binding to the solubilized preparation: guanosine 5'-0-(3-thiotriphosphate)(K/sub 1/2/ = 2.5 nM), guanylyl-imidodiphosphate (K/sub 1/2/ = 10 nM), guanosine triphosphate (K/sub 1/2/ = 34 nM) and adenylyl-imidodiphosphate (K/sub 1/2/ > 1 mM). In the presence of guanylyl-imidodiphosphate (0.4 mM), the receptor population displayed monotonic binding parameters with a K/sub d/ for (/sup 3/H)-prazosin of 1.16 nM by Scatchard analysis. Competition curves against (/sup 3/H)-prazosin with the antagonists phentolamine and yohimbine revealed respective K/sub i/'s of .089 ..mu..M and 1.8 ..mu..M; curves with the agonists norepinephrine and isoproterenol yielded respective K/sub i/'s of 6.2..mu..M and 360 ..mu..M. Competition curves performed in the absence of guanyl nucleotide were complex demonstrating an apparent increase in affinity for agonists and an apparent decrease in affinity for antagonists. These curve shifts are consistent with the conversion of receptor to and from the guanyl nucleotide-sensitive state as a function of competing ligand concentration.

  14. Reproductive factors, hormone use, estrogen receptor expression and risk of non small-cell lung cancer in women.

    Science.gov (United States)

    Schwartz, Ann G; Wenzlaff, Angela S; Prysak, Geoffrey M; Murphy, Valerie; Cote, Michele L; Brooks, Sam C; Skafar, Debra F; Lonardo, Fulvio

    2007-12-20

    Estrogen receptor (ER) expression in lung tumors suggests that estrogens may play a role in the development of lung cancer. We evaluated the role of hormone-related factors in determining risk of non-small-cell lung cancer (NSCLC) in women. We also evaluated whether risk factors were differentially associated with cytoplasmic ER-alpha and/or nuclear ER-beta expression-defined NSCLC in postmenopausal women. Population-based participants included women aged 18 to 74 years diagnosed with NSCLC in metropolitan Detroit between November 1, 2001 and October 31, 2005. Population-based controls were identified through random digit dialing, matched to patient cases on race and 5-year age group. Interview data were analyzed for 488 patient cases (241 with tumor ER results) and 498 controls. Increased duration of hormone replacement therapy (HRT) use in quartiles was associated with decreased risk of NSCLC in postmenopausal women (odds ratio = 0.88; 95% CI, 0.78 to 1.00; P = .04), adjusting for age, race, pack-years, education, family history of lung cancer, current body mass index, years exposed to second-hand smoke in the workplace, and obstructive lung disease history. Among postmenopausal women, ever using HRT, increasing HRT duration of use in quartiles, and increasing quartiles of estrogen use were significant predictors of reduced risk of NSCLC characterized as ER-alpha and/or ER-beta positive. None of the hormone-related variables were associated with nuclear ER-alpha- or ER-beta-negative NSCLC. These findings suggest that postmenopausal hormone exposures are associated with reduced risk of ER-alpha- and ER-beta-expressing NSCLC. Understanding tumor characteristics may direct development of targeted treatment for this disease.

  15. Sleep in mice with nonfunctional growth hormone-releasing hormone receptors.

    Science.gov (United States)

    Obal, Ferenc; Alt, Jeremiah; Taishi, Ping; Gardi, Janos; Krueger, James M

    2003-01-01

    The role of the somatotropic axis in sleep regulation was studied by using the lit/lit mouse with nonfunctional growth hormone (GH)-releasing hormone (GHRH) receptors (GHRH-Rs) and control heterozygous C57BL/6J mice, which have a normal phenotype. During the light period, the lit/lit mice displayed significantly less spontaneous rapid eye movement sleep (REMS) and non-REMS (NREMS) than the controls. Intraperitoneal injection of GHRH (50 microg/kg) failed to promote sleep in the lit/lit mice, whereas it enhanced NREMS in the heterozygous mice. Subcutaneous infusion of GH replacement stimulated weight gain, increased the concentration of plasma insulin-like growth factor-1 (IGF-1), and normalized REMS, but failed to restore normal NREMS in the lit/lit mice. The NREMS response to a 4-h sleep deprivation was attenuated in the lit/lit mice. In control mice, intraperitoneal injection of ghrelin (400 microg/kg) elicited GH secretion and promoted NREMS, and intraperitoneal administration of the somatostatin analog octretotide (Oct, 200 microg/kg) inhibited sleep. In contrast, these responses were missing in the lit/lit mice. The results suggest that GH promotes REMS whereas GHRH stimulates NREMS via central GHRH-Rs and that GHRH is involved in the mediation of the sleep effects of ghrelin and somatostatin.

  16. Nicotinic Receptor Alpha7 Expression during Mouse Adrenal Gland Development

    Science.gov (United States)

    Gahring, Lorise C.; Myers, Elizabeth; Palumbos, Sierra; Rogers, Scott W.

    2014-01-01

    The nicotinic acetylcholine receptor alpha 7 (α7) is a ligand-activated ion channel that contributes to a diversity of cellular processes involved in development, neurotransmission and inflammation. In this report the expression of α7 was examined in the mouse developing and adult adrenal gland that expresses a green fluorescent protein (GFP) reporter as a bi-cistronic extension of the endogenous α7 transcript (α7G). At embryonic day 12.5 (E12.5) α7G expression was associated with the suprarenal ganglion and precursor cells of the adrenal gland. The α7G cells are catecholaminergic chromaffin cells as reflected by their progressive increase in the co-expression of tyrosine hydroxylase (TH) and dopamine-beta-hydroxylase (DBH) that is complete by E18.5. In the adult, α7G expression is limited to a subset of chromaffin cells in the adrenal medulla that cluster near the border with the adrenal cortex. These chromaffin cells co-express α7G, TH and DBH, but they lack phenylethanolamine N-methyltransferase (PNMT) consistent with only norepinephrine (NE) synthesis. These cell groups appear to be preferentially innervated by pre-ganglionic afferents identified by the neurotrophin receptor p75. No afferents identified by beta-III tubulin, neurofilament proteins or p75 co-expressed α7G. Occasional α7G cells in the pre-E14.5 embryos express neuronal markers consistent with intrinsic ganglion cells and in the adult some α7G cells co-express glutamic acid decarboxylase. The transient expression of α7 during adrenal gland development and its prominent co-expression by a subset of NE chromaffin cells in the adult suggests that the α7 receptor contributes to multiple aspects of adrenal gland development and function that persist into adulthood. PMID:25093893

  17. Sustained cyclic AMP production by parathyroid hormone receptor endocytosis.

    Science.gov (United States)

    Ferrandon, Sébastien; Feinstein, Timothy N; Castro, Marian; Wang, Bin; Bouley, Richard; Potts, John T; Gardella, Thomas J; Vilardaga, Jean-Pierre

    2009-10-01

    Cell signaling mediated by the G protein-coupled parathyroid hormone receptor type 1 (PTHR) is fundamental to bone and kidney physiology. It has been unclear how the two ligand systems--PTH, endocrine and homeostatic, and PTH-related peptide (PTHrP), paracrine--can effectively operate with only one receptor and trigger different durations of the cAMP responses. Here we analyze the ligand response by measuring the kinetics of activation and deactivation for each individual reaction step along the PTHR signaling cascade. We found that during the time frame of G protein coupling and cAMP production, PTHrP(1-36) action was restricted to the cell surface, whereas PTH(1-34) had moved to internalized compartments where it remained associated with the PTHR and Galpha(s), potentially as a persistent and active ternary complex. Such marked differences suggest a mechanism by which PTH and PTHrP induce differential responses, and these results indicate that the central tenet that cAMP production originates exclusively at the cell membrane must be revised.

  18. Effects of alpha-melanocyte-stimulating hormone on mitochondrial energy metabolism in rats of different age-groups.

    Science.gov (United States)

    Feichtinger, René G; Pétervári, Erika; Zopf, Michaela; Vidali, Silvia; Aminzadeh-Gohari, Sepideh; Mayr, Johannes A; Kofler, Barbara; Balaskó, Márta

    2017-08-01

    Hypothalamic alpha-melanocyte-stimulating hormone (α-MSH) is a key catabolic mediator of energy homeostasis. Its anorexigenic and hypermetabolic effects show characteristic age-related alterations that may be part of the mechanism of middle-aged obesity and geriatric anorexia/cachexia seen in humans and other mammals. We aimed to investigate the role of α-MSH in mitochondrial energy metabolism during the course of aging in a rodent model. To determine the role of α-MSH in mitochondrial energy metabolism in muscle, we administered intracerebroventricular (ICV) infusions of α-MSH for 7-days to different age-groups of male Wistar rats. The activities of oxidative phosphorylation complexes I to V and citrate synthase were determined and compared to those of age-matched controls. We also quantified mitochondrial DNA (mtDNA) copy number and measured the expression of the master regulators of mitochondrial biogenesis, peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and peroxisome proliferator-activated receptor gamma (PPARγ). The peptide reduced weight gain in juvenile rats to one fifth of that of controls and increased the weight loss in older animals by about five fold. Mitochondrial DNA copy number inversely correlated with changes in body weight in controls, but not in α-MSH-treated animals. The strong increase in body weight in young rats was associated with a low mtDNA copy number and high PPARγ mRNA levels in controls. Expression of PGC-1α and PPARγ declined with age, whereas OXPHOS and citrate synthase enzyme activities were unchanged. In contrast, α-MSH treatment suppressed OXPHOS enzyme and citrate synthase activity. In conclusion, our results showed age-related differences in the metabolic effects of α-MSH. In addition, administration of α-MSH suppressed citrate synthase and OXPHOS activities independent of age. These findings suggest that α-MSH exposure may inhibit mitochondrial biogenesis. Copyright © 2016 Elsevier

  19. Genomic organization of a receptor from sea anemones, structurally and evolutionary related to glycoprotein hormone receptors from mamals

    DEFF Research Database (Denmark)

    Vibede, N; Hauser, Frank; Williamson, M

    1998-01-01

    Abstract Cnidarians (e.g., sea anemones and corals) are the lowest animal group having a nervous system. Previously, we cloned a receptor from sea anemones that showed a strong structural similarity to the glycoprotein hormone (TSH, FSH, LH/CG) receptors from mammals. Here, we determine the genomic...... organization of this sea anemone receptor. The receptor gene contains eight introns that are all localized within a region coding for the large extracellular N terminus. These introns occur at the same positions and have the same intron phasing as eight introns in the genes coding for the mammalian...... glycoprotein hormone receptors, indicating that the cnidarian and mammalian receptor genes are evolutionarily related. As with the mammalian receptor genes, the sea anemone receptor gene does not contain introns in the region coding for the transmembrane and intracellular domains. Southern blot analyses show...

  20. Two farnesoid X receptor alpha isoforms in Japanese medaka (Oryzias latipes) are differentially activated in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Howarth, Deanna L. [Integrated Toxicology and Environmental Health Program and Nicholas School of the Environment and Earth Sciences, Duke University, Durham, NC 27708 (United States); Hagey, Lee R. [Department of Medicine, University of California at San Diego, La Jolla, CA 92093 (United States); Law, Sheran H.W. [Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695 (United States); Ai, Ni [Department of Pharmacology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway, NJ 08854 (United States); Krasowski, Matthew D. [Department of Pathology, University of Iowa Hospitals and Clinics, Iowa City, IA (United States); Ekins, Sean [Department of Pharmacology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway, NJ 08854 (United States); Collaboration in Chemistry, Jenkintown, PA 19046 (United States); Department of Pharmaceutical Sciences, University of Maryland, Baltimore, MD 21201 (United States); Moore, John T. [GlaxoSmithKline Discovery Research, Research Triangle Park, NC 27709 (United States); Kollitz, Erin M. [Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695 (United States); Hinton, David E. [Integrated Toxicology and Environmental Health Program and Nicholas School of the Environment and Earth Sciences, Duke University, Durham, NC 27708 (United States); Kullman, Seth W., E-mail: swkullma@ncsu.edu [Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695 (United States)

    2010-07-01

    The nuclear receptor farnesoid X receptor alpha (FXR{alpha}, NR1H4) is activated by bile acids in multiple species including mouse, rat, and human and in this study we have identified two isoforms of Fxr{alpha} in Japanese medaka (Oryzias latipes), a small freshwater teleost. Both isoforms share a high amino acid sequence identity to mammalian FXR{alpha} ({approx}70% in the ligand-binding domain). Fxr{alpha}1 and Fxr{alpha}2 differ within the AF1 domain due to alternative splicing at the fourth intron-exon boundary. This process results in Fxr{alpha}1 having an extended N-terminus compared to Fxr{alpha}2. A Gal4DBD-Fxr{alpha}LBD fusion construct was activated by chenodeoxycholic, cholic, deoxycholic and lithocholic acids, and the synthetic agonist GW4064 in transient transactivation assays. Activation of the Gal4DBD-Fxr{alpha}LBD fusion construct was enhanced by addition of PGC-1{alpha}, as demonstrated through titration assays. Surprisingly, when the full-length versions of the two Fxr{alpha} isoforms were compared in transient transfection assays, Fxr{alpha}2 was activated by C{sub 24} bile acids and GW4064, while Fxr{alpha}1 was not significantly activated by any of the compounds tested. Since the only significant difference between the full-length constructs was sequence in the AF1 domain, these experiments highlight a key functional region in the Fxr{alpha} AF1 domain. Furthermore, mammalian two-hybrid studies demonstrated the ability of Fxr{alpha}2, but not Fxr{alpha}1, to interact with PGC-1{alpha} and SRC-1, and supported our results from the transient transfection reporter gene activation assays. These data demonstrate that both mammalian and teleost FXR (Fxr{alpha}2 isoform) are activated by primary and secondary bile acids.

  1. Designer interface peptide grafts target estrogen receptor alpha dimerization

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, S. [Laboratory of Computational Biophysics & Bioengineering, Department of Physics, Tougaloo College, Tougaloo, MS 39174 (United States); Asare, B.K. [Department of Pharmacology and Toxicology, University of Buffalo, Buffalo, NY 14214 (United States); Biswas, P.K., E-mail: pbiswas@tougaloo.edu [Laboratory of Computational Biophysics & Bioengineering, Department of Physics, Tougaloo College, Tougaloo, MS 39174 (United States); Rajnarayanan, R.V., E-mail: rajendra@buffalo.edu [Department of Pharmacology and Toxicology, University of Buffalo, Buffalo, NY 14214 (United States)

    2016-09-09

    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. 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

  2. Thyroid-Stimulating Hormone Receptor Antibodies in Pregnancy: Clinical Relevance

    Science.gov (United States)

    Bucci, Ines; Giuliani, Cesidio; Napolitano, Giorgio

    2017-01-01

    Graves’ disease is the most common cause of thyrotoxicosis in women of childbearing age. Approximately 1% of pregnant women been treated before, or are being treated during pregnancy for Graves’ hyperthyroidism. In pregnancy, as in not pregnant state, thyroid-stimulating hormone (TSH) receptor (TSHR) antibodies (TRAbs) are the pathogenetic hallmark of Graves’ disease. TRAbs are heterogeneous for molecular and functional properties and are subdivided into activating (TSAbs), blocking (TBAbs), or neutral (N-TRAbs) depending on their effect on TSHR. The typical clinical features of Graves’ disease (goiter, hyperthyroidism, ophthalmopathy, dermopathy) occur when TSAbs predominate. Graves’ disease shows some peculiarities in pregnancy. The TRAbs disturb the maternal as well as the fetal thyroid function given their ability to cross the placental barrier. The pregnancy-related immunosuppression reduces the levels of TRAbs in most cases although they persist in women with active disease as well as in women who received definitive therapy (radioiodine or surgery) before pregnancy. Changes of functional properties from stimulating to blocking the TSHR could occur during gestation. Drug therapy is the treatment of choice for hyperthyroidism during gestation. Antithyroid drugs also cross the placenta and therefore decrease both the maternal and the fetal thyroid hormone production. The management of Graves’ disease in pregnancy should be aimed at maintaining euthyroidism in the mother as well as in the fetus. Maternal and fetal thyroid dysfunction (hyperthyroidism as well as hypothyroidism) are in fact associated with several morbidities. Monitoring of the maternal thyroid function, TRAbs measurement, and fetal surveillance are the mainstay for the management of Graves’ disease in pregnancy. This review summarizes the biochemical, immunological, and therapeutic aspects of Graves’ disease in pregnancy focusing on the role of the TRAbs in maternal and fetal

  3. Thyroid-Stimulating Hormone Receptor Antibodies in Pregnancy: Clinical Relevance

    Directory of Open Access Journals (Sweden)

    Ines Bucci

    2017-06-01

    Full Text Available Graves’ disease is the most common cause of thyrotoxicosis in women of childbearing age. Approximately 1% of pregnant women been treated before, or are being treated during pregnancy for Graves’ hyperthyroidism. In pregnancy, as in not pregnant state, thyroid-stimulating hormone (TSH receptor (TSHR antibodies (TRAbs are the pathogenetic hallmark of Graves’ disease. TRAbs are heterogeneous for molecular and functional properties and are subdivided into activating (TSAbs, blocking (TBAbs, or neutral (N-TRAbs depending on their effect on TSHR. The typical clinical features of Graves’ disease (goiter, hyperthyroidism, ophthalmopathy, dermopathy occur when TSAbs predominate. Graves’ disease shows some peculiarities in pregnancy. The TRAbs disturb the maternal as well as the fetal thyroid function given their ability to cross the placental barrier. The pregnancy-related immunosuppression reduces the levels of TRAbs in most cases although they persist in women with active disease as well as in women who received definitive therapy (radioiodine or surgery before pregnancy. Changes of functional properties from stimulating to blocking the TSHR could occur during gestation. Drug therapy is the treatment of choice for hyperthyroidism during gestation. Antithyroid drugs also cross the placenta and therefore decrease both the maternal and the fetal thyroid hormone production. The management of Graves’ disease in pregnancy should be aimed at maintaining euthyroidism in the mother as well as in the fetus. Maternal and fetal thyroid dysfunction (hyperthyroidism as well as hypothyroidism are in fact associated with several morbidities. Monitoring of the maternal thyroid function, TRAbs measurement, and fetal surveillance are the mainstay for the management of Graves’ disease in pregnancy. This review summarizes the biochemical, immunological, and therapeutic aspects of Graves’ disease in pregnancy focusing on the role of the TRAbs in maternal and

  4. Comparative analysis of nuclear estrogen receptor alpha and beta interactomes in breast cancer cells.

    Science.gov (United States)

    Nassa, Giovanni; Tarallo, Roberta; Guzzi, Pietro H; Ferraro, Lorenzo; Cirillo, Francesca; Ravo, Maria; Nola, Ernesto; Baumann, Marc; Nyman, Tuula A; Cannataro, Mario; Ambrosino, Concetta; Weisz, Alessandro

    2011-03-01

    Estrogen Receptor alpha and beta (ER-α and -β) are members of the nuclear receptor family of transcriptional regulators with distinct roles in mediating estrogen dependent breast cancer cell growth and differentiation. Following activation by the hormone, these proteins undergo conformation changes and accumulate in the nucleus, where they bind to chromatin at regulatory sites as homo- and/or heterodimers and assemble in large multiprotein complexes. Although the two ERs share a conserved structure, they exert specific and distinct functional roles in normal and transformed mammary epithelial cells and other cell types. To investigate the molecular bases of such differences, we performed a comparative computational analysis of the nuclear interactomes of the two ER subtypes, exploiting two datasets of receptor interacting proteins identified in breast cancer cell nuclei by Tandem Affinity Purification for their ability to associate in vivo with ligand-activated ER-α and/or ER-β. These datasets comprise 498 proteins, of which only 70 are common to both ERs, suggesting that differences in the nature of the two ER interactomes are likely to sustain the distinct roles of the two receptor subtypes. Functional characterization of the two interactomes and their topological analysis, considering node degree and closeness of the networks, confirmed this possibility. Indeed, clustering and network dissection highlighted the presence of distinct and ER subtype-specific subnetworks endowed with defined functions. Altogether, these data provide new insights on the protein-protein interaction networks controlled by ER-α and -β that mediate their ability to transduce estrogen signaling in breast cancer cells.

  5. Nuclear hormone receptor signals as new therapeutic targets for urothelial carcinoma.

    Science.gov (United States)

    Miyamoto, H; Zheng, Y; Izumi, K

    2012-01-01

    Unlike prostate and breast cancers, urothelial carcinoma of the urinary bladder is not yet considered as an endocrine-related neoplasm, and hormonal therapy for bladder cancer remains experimental. Nonetheless, there is increasing evidence indicating that nuclear hormone receptor signals are implicated in the development and progression of bladder cancer. Androgen-mediated androgen receptor (AR) signals have been convincingly shown to induce bladder tumorigenesis. Androgens also promote the growth of AR-positive bladder cancer cells, although it is controversial whether AR plays a dominant role in bladder cancer progression. Both stimulatory and inhibitory functions of estrogen receptor signals in bladder cancer have been reported. Various studies have also demonstrated the involvement of other nuclear receptors, including progesterone receptor, glucocorticoid receptor, vitamin D receptor, and retinoid receptors, as well as some orphan receptors, in bladder cancer. This review summarizes and discusses available data suggesting the modulation of bladder carcinogenesis and cancer progression via nuclear hormone receptor signaling pathways. These pathways have the potential to be an extremely important area of bladder cancer research, leading to the development of effective chemopreventive/therapeutic approaches, using hormonal manipulation. Considerable uncertainty remains regarding the selection of patients who are likely to benefit from hormonal therapy and optimal options for the treatment.

  6. Hormone receptors in gills of smolting Atlantic salmon, Salmo salar

    DEFF Research Database (Denmark)

    Kiilerich, Pia; Kristiansen, Karsten; Madsen, Steffen

    2007-01-01

    This is the first study to report concurrent dynamics in mRNA expression of growth hormone receptor (GHR), prolactin receptor (PRLR), gluco- and mineralocorticoid receptor (GR and MR) and the 11beta-hydroxysteroid dehydrogenase type-2 enzyme (11beta-HSD2) in Atlantic salmon (Salmo salar) gill...

  7. Evaluating Serum Markers for Hormone Receptor-Negative Breast Cancer.

    Directory of Open Access Journals (Sweden)

    Michèl Schummer

    Full Text Available Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death in females worldwide. Death rates have been declining, largely as a result of early detection through mammography and improved treatment, but mammographic screening is controversial because of over-diagnosis of breast disease that might not require treatment, and under-diagnosis of cancer in women with dense breasts. Breast cancer screening could be improved by pairing mammography with a tumor circulating marker, of which there are currently none. Given genomic similarities between the basal breast cancer subtype and serous ovarian cancer, and given our success in identifying circulating markers for ovarian cancer, we investigated the performance in hormone receptor-negative breast cancer detection of both previously identified ovarian serum markers and circulating markers associated with transcripts that were differentially expressed in breast cancer tissue compared to healthy breast tissue from reduction mammaplasties.We evaluated a total of 15 analytes (13 proteins, 1 miRNA, 1 autoantibody in sera drawn at or before breast cancer surgery from 43 breast cancer cases (28 triple-negative-TN-and 15 hormone receptor-negative-HRN-/ HER2-positive and 87 matched controls.In the analysis of our whole cohort of breast cancer cases, autoantibodies to TP53 performed significantly better than the other selected 14 analytes showing 25.6% and 34.9% sensitivity at 95% and 90% specificity respectively with AUC: 0.7 (p<0.001. The subset of 28 TN cancers showed very similar results. We observed no correlation between anti-TP53 and the 14 other markers; however, anti-TP53 expression correlated with Body-Mass-Index. It did not correlate with tumor size, positive lymph nodes, tumor stage, the presence of metastases or recurrence.None of the 13 serum proteins nor miRNA 135b identified women with HRN or TN breast cancer. TP53 autoantibodies identified women with HRN breast

  8. Autonomic function in mice lacking alpha5 neuronal nicotinic acetylcholine receptor subunit.

    Science.gov (United States)

    Wang, Ningshan; Orr-Urtreger, Avi; Chapman, Joab; Rabinowitz, Ruth; Nachman, Rachel; Korczyn, Amos D

    2002-07-15

    Neuronal acetylcholine nicotinic receptors (nAChR) are composed of 12 subunits (alpha2-10, beta2-4), of which alpha3, alpha5, alpha7, beta2 and beta4 subunits are known to exist in the autonomic nervous system (ANS). alpha5 subunits possess unique biophysical and pharmacological properties. The present study was undertaken to examine the functional role and pharmacological properties of the nAChR alpha5 subunits in the ANS using mice lacking alpha5 nAChR subunits (alpha5-/-). These mice grew to normal size showing no obvious physical or neurological deficit. They also showed normality in thermoregulation, pupil size and resting heart rate under physiological conditions. The heart rate and rectal temperature did not differ between alpha5-/- and wild-type mice during exposure to cold stress. An impairment of cardiac parasympathetic ganglionic transmission was observed during high frequency vagal stimulation, which caused cardiac arrest in all wild-type animals while alpha5-/- mice were more resistant. Deficiency of alpha5 subunits strikingly increased the sensitivity to a low concentration of hexamethonium, leading to a nearly complete blockade of bradycardia in response to vagal stimulation. Such a concentration of hexamethonium only slightly depressed the effects of vagal stimulation in control mice. Deficiency of alpha5 subunits significantly increased ileal contractile responses to cytisine and epibatidine. These results suggest that alpha5 subunits may affect the affinity and sensitivity of agonists and antagonists in the native receptors. Previous studies revealed that alpha5 subunits form functional receptors only in combination with other alpha and beta subunits. Thus, the data presented here imply that alpha5 subunits modulate the activity of nAChR in autonomic ganglia in vivo.

  9. Cardiac Alpha1-Adrenergic Receptors: Novel Aspects of Expression, Signaling Mechanisms, Physiologic Function, and Clinical Importance

    Science.gov (United States)

    O’Connell, Timothy D.; Jensen, Brian C.; Baker, Anthony J.

    2014-01-01

    Adrenergic receptors (AR) are G-protein-coupled receptors (GPCRs) that have a crucial role in cardiac physiology in health and disease. Alpha1-ARs signal through Gαq, and signaling through Gq, for example, by endothelin and angiotensin receptors, is thought to be detrimental to the heart. In contrast, cardiac alpha1-ARs mediate important protective and adaptive functions in the heart, although alpha1-ARs are only a minor fraction of total cardiac ARs. Cardiac alpha1-ARs activate pleiotropic downstream signaling to prevent pathologic remodeling in heart failure. Mechanisms defined in animal and cell models include activation of adaptive hypertrophy, prevention of cardiac myocyte death, augmentation of contractility, and induction of ischemic preconditioning. Surprisingly, at the molecular level, alpha1-ARs localize to and signal at the nucleus in cardiac myocytes, and, unlike most GPCRs, activate “inside-out” signaling to cause cardioprotection. Contrary to past opinion, human cardiac alpha1-AR expression is similar to that in the mouse, where alpha1-AR effects are seen most convincingly in knockout models. Human clinical studies show that alpha1-blockade worsens heart failure in hypertension and does not improve outcomes in heart failure, implying a cardioprotective role for human alpha1-ARs. In summary, these findings identify novel functional and mechanistic aspects of cardiac alpha1-AR function and suggest that activation of cardiac alpha1-AR might be a viable therapeutic strategy in heart failure. PMID:24368739

  10. Screening of hormone-like activities in bottled waters available in Southern Spain using receptor-specific bioassays.

    Science.gov (United States)

    Real, Macarena; Molina-Molina, José-Manuel; Jiménez-Díaz, Inmaculada; Arrebola, Juan Pedro; Sáenz, José-María; Fernández, Mariana F; Olea, Nicolás

    2015-01-01

    Bottled water consumption is a putative source of human exposure to endocrine-disrupting chemicals (EDCs). Research has been conducted on the presence of chemicals with estrogen-like activity in bottled waters and on their estrogenicity, but few data are available on the presence of hormonal activities associated with other nuclear receptors (NRs). The aim of this study was to determine the presence of endocrine activities dependent on the activation of human estrogen receptor alpha (hERa) and/or androgen receptor (hAR) in water in glass or plastic bottles sold to consumers in Southern Spain. Hormone-like activities were evaluated in 29 bottled waters using receptor-specific bioassays based on reporter gene expression in PALM cells [(anti-)androgenicity] and cell proliferation assessment in MCF-7 cells [(anti-)estrogenicity] after optimized solid phase extraction (SPE). All of the water samples analyzed showed hormonal activity. This was estrogenic in 79.3% and anti-estrogenic in 37.9% of samples and was androgenic in 27.5% and anti-androgenic in 41.3%, with mean concentrations per liter of 0.113pM 17β-estradiol (E2) equivalent units (E2Eq), 11.01pM anti-estrogen (ICI 182780) equivalent units (ICI 182780Eq), 0.33pM methyltrienolone (R1881) equivalent units (R1881Eq), and 0.18nM procymidone equivalent units (ProcEq). Bottled water consumption contributes to EDC exposure. Hormone-like activities observed in waters from both plastic and glass bottles suggest that plastic packaging is not the sole source of contamination and that the source of the water and bottling process may play a role, among other factors. Further research is warranted on the cumulative effects of long-term exposure to low doses of EDCs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Ontogenic increase in PGE2 and PGF2 alpha receptor density in brain microvessels of pigs.

    OpenAIRE

    Li, D. Y.; Varma, D. R.; Chemtob, S.

    1994-01-01

    1. The hypothesis that the relative vasoconstrictor ineffectiveness of prostaglandin E2 (PGE2) and PGF2 alpha on cerebral vessels of newborn pigs might be due to fewer receptors for these prostanoids was tested by comparing receptors for PGE2 (EP) and PGF2 alpha (FP) in cerebral microvessels from newborn and adult pigs. 2. Specific binding of [3H]-PGE2 and [3H]-PGF2 alpha to membranes prepared from brain microvessels showed that EP and FP receptor density (Bmax) in tissues from newborn animal...

  12. Common non-hormone binding component in non-transformed chick oviduct receptors of four steroid hormones.

    Science.gov (United States)

    Joab, I; Radanyi, C; Renoir, M; Buchou, T; Catelli, M G; Binart, N; Mester, J; Baulieu, E E

    Steroid hormones produce a response in target cells by binding to hormone-specific soluble receptors, which undergo a transformational change, leading to their interaction with chromatin and to modified gene expression. In a previous paper, we described a monoclonal antibody, BF4, that specifically recognizes and binds the non-transformed '8S' form of chicken oviduct progesterone receptor (8S-PR). We now show that BF4 does not form an immune complex with the 4S transformed form of 3H-progestin-labelled progesterone receptor, but does interact with the 8S non-transformed forms of the oestrogen, androgen and glucocorticosteroid receptors. Our results suggest that the antigenic determinant recognized by BF4 is present on a non-hormone binding unit, which we identify as a polypeptide of molecular weight (MW) 90,000 in the case of the progesterone receptor, and that this unit is common to other 8S non-transformed chicken steroid receptors.

  13. Interactions of the bovine brain A1-adenosine receptor with recombinant G protein alpha-subunits. Selectivity for rGi alpha-3.

    Science.gov (United States)

    Freissmuth, M; Schütz, W; Linder, M E

    1991-09-25

    The ability of the bovine brain A1-adenosine receptor to discriminate between different G protein subtypes was tested using G protein alpha-subunits synthesized in Escherichia coli (rG alpha-subunits). When combined with a 3-fold molar excess of beta gamma-subunit purified from bovine brain and used at high concentrations, all three subtypes of rGi alpha (rGi alpha-1, rGi alpha-2, and rGi alpha-3) and rGo alpha were capable of reconstituting guanine nucleotide-sensitive high-affinity binding of the agonist radioligand (-)-N6-3-[125I] (iodo-4-hydroxyphenylisopropyl) adenosine ([125I]HPIA) to the purified A1-adenosine receptor (Kd approximately 1.2 nM). Titration of the A1-adenosine receptor with increasing amounts of rG alpha revealed a approximately 10-fold higher affinity for rGi alpha-3 compared with rGi alpha-1, rGi alpha-2, and rGo alpha. This selectivity was also observed in the absence of beta gamma. Other alpha-subunits (rGs alpha-s, rGs alpha-L, rGs alpha PT, and rGz alpha) did not promote [125I]HPIA binding to the purified receptor. In N-ethylmaleimide-treated bovine brain membranes, rGi alpha-3 was the only rG alpha-subunit capable of reconstituting high-affinity agonist binding. Similarly, rGi alpha-3 competed potently with rGo alpha for activation by the agonist-liganded A1-adenosine receptor, whereas a approximately 50-fold molar excess of rGo alpha was required to quench the receptor-mediated release of [alpha-32P]GDP from rGi alpha-3. Hence, in spite of the extensive homology between alpha-subunits belonging to the Gi/Go group, the A1-adenosine receptor appears to discriminate between the subtypes. This specificity is likely to govern transmembrane signaling pathways in vivo.

  14. Growth hormone receptor/binding protein: physiology and function.

    Science.gov (United States)

    Herington, A C; Ymer, S I; Stevenson, J L; Roupas, P

    1994-07-01

    Soluble truncated forms of the growth hormone receptor (GHR) are present in the circulation of many species and are also produced by many tissues/cell types. The major high-affinity forms of these GH-binding proteins (GHBP) are derived by alternative splicing of GHR mRNA in rodents, but probably by proteolytic cleavage in other species. Questions still remain with respect to the origins, native molecular form(s), physiology, and function of the GHBPs, however. The observation that GH induces dimerization of the soluble GHBP and membrane GHR, and that dimerization of GHR appears to be critical for GH bioactivity suggests that the presentation of GH to target cells, in an unbound form or as a monomeric or dimeric complex with GHBP, may have significant implications for the ability of GH to activate specific postreceptor signaling pathways (tyrosine kinase, protein kinase C, G-protein pathways) known to be utilized by GH for its diverse biological effects. This minireview addresses some of these aspects and highlights several new questions which have arisen as a result of recent advances in our understanding of the structure, function, and signaling mechanisms of the membrane bound GHR.

  15. Growth hormone receptor/binding protein: Physiology and function

    Energy Technology Data Exchange (ETDEWEB)

    Herington, A.C.; Ymer, S.I.; Stevenson, J.L.; Roupas, P. [Royal Children`s Hospital, Melbourne (Australia)

    1994-12-31

    Soluble truncated forms of the growth hormone receptor (GHR) are present in the circulation of many species and are also produced by many tissues/cell types. The major high-affinity forms of these GH-binding proteins (GHBP) are derived by alternative splicing of GHR mRNA in rodents, but probably by proteolytic cleavage in other species. Questions still remain with respect to the origins, native molecular forms(s), physiology, and function of the GHBPs, however. The observation that GH induces dimerization of the soluble GHBP and a membrane GHR, and that dimerization of GHR appears to be critical for GH bioactivity suggests that the presentation of GH to target cells, in an unbound form or as a monomeric or dimeric complex with GHBP, may have significant implications for the ability of GH to activate specific postreceptor signaling pathways (tyrosine kinase, protein kinase C, G-protein pathways) known to be utilized by GH for its diverse biological effects. This minireview addresses some of these aspects and highlights several new questions which have arisen as a result of recent advances in our understanding of the structure, function, and signaling mechanisms of the membrane bound GHR. 43 refs.

  16. Insulin-like growth factors (IGFs) stimulate the release of alpha 1-antichymotrypsin and soluble IGF-II/mannose 6-phosphate receptor from MCF7 breast cancer cells.

    Science.gov (United States)

    Confort, C; Rochefort, H; Vignon, F

    1995-09-01

    The growth of hormone-responsive MCF7 human breast cancer cells is controlled by steroid hormones and growth factors. By metabolic labeling of cells grown in steroid- and growth factor-stripped serum conditions, we show that insulin-like growth factors (IGF-I and IGF-II) increase by approximately 5-fold the release of several proteins including cathepsin D, alpha 1-antichymotrypsin, and soluble forms of the multifunctional IGF-II/mannose 6-phosphate (M6P) receptor. Two soluble forms of IGF-II/M6P receptors were detected, one major (approximately 260 kilodaltons) and one minor (approximately 85 kilodaltons) that probably represents a proteolytic fragment of the larger soluble molecule. IGFs increased receptor release in a dose-dependent fashion with 50-60% of newly synthesized receptor released at 5-10 nM IGFs. The release of IGF-II/M6P receptors correlated with the levels of secreted cathepsin D in different human breast cancer cells or in rats stable transfectants that are constitutively expressing variable levels of human cathepsin D. IGFs had a stronger effect on IGF-II/M6P receptor release, whereas estradiol treatment preferentially enhanced the release of protease and antiprotease. We thus demonstrate that in human breast cancer cells, IGFs not only act as strong mitogens but also regulate release of alpha 1-antichymotrypsin, IGF-II/M6P-soluble receptor, and cathepsin D; three proteins that potentially regulate cell proliferation and/or invasion.

  17. Introduction of exogenous growth hormone receptors augments growth hormone-responsive insulin biosynthesis in rat insulinoma cells

    DEFF Research Database (Denmark)

    Billestrup, N; Møldrup, A; Serup, P

    1990-01-01

    The stimulation of insulin biosynthesis in the pancreatic insulinoma cell line RIN5-AH by growth hormone (GH) is initiated by GH binding to specific receptors. To determine whether the recently cloned rat hepatic GH receptor is able to mediate the insulinotropic effect of GH, we have transfected...... of GH receptors in one clone (1.24) selected for detailed analysis was increased 2.6-fold compared to untransfected cells. The increased GH receptor expression was accompanied by an increased responsiveness to GH. Thus, the maximal GH-stimulated increase of insulin biosynthesis was 4.1-fold in 1...... magnitude of GH-stimulated insulin biosynthesis. A close stoichiometric relationship between the level of receptor expression and the level of GH-stimulated insulin biosynthesis was observed. We conclude from these results that the hepatic GH receptor is able to mediate the effect of GH on insulin...

  18. Desethylamiodarone is a noncompetitive inhibitor of the binding of thyroid hormone to the thyroid hormone beta 1-receptor protein

    NARCIS (Netherlands)

    Bakker, O.; van Beeren, H. C.; Wiersinga, W. M.

    1994-01-01

    It has been hypothesized that amiodarone (A), a potent antiarrythmic and antianginal drug, induces a local hypothyroid-like condition in extrathyroidal tissues. This might be related to competitive antagonism of A for the thyroid hormone receptor reported in some studies but denied in others. These

  19. Overexpression of thyroid hormone beta1 nuclear receptor is associated with an increased proliferation of human hepatoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Lin, K.; Lin, Y.; McPhie, P. [Chang-Gung College of Medicine and Technology, Graduate Institute of Clinical Medicine, Taoyuan (Taiwan, Province of China); Cheng, S. [National Cancer Inst., Bethesda, MD (United States)

    1994-12-31

    It is evaluated the expression of thyroid hormone nuclear receptors (TRs) and their possible roles in the carcinogenesis of human hepatocarcinoma. The expression of TR{beta}1 and TR{alpha} genes was evaluated at both the mRNA and protein levels. The expression of TR{beta}1 and TR{alpha}1 mRNAs is similar to those found in normal liver. However, the expression of TR isoform proteins depends on the cell-type. The expression of TRaplha1 protein is low in all cell lines examined. However, TR{Beta}1 protein is overexpressed in Mahlavu, SK-Hep-1, and HA22T, moderately expressed in J5, J7, and J328 and is very low HepG2, Hep3B, and PLC/PRF/5 cells. The proliferation of cells in which TR{beta}1 is overexpressed is stimulated by the thyroid hormone, 3,3`,5- triiodo-L-thyronine. These results suggest that TR{beta}1, not TR{alpha}1, is probably involved in the prolifaration of hepatoma cells.

  20. Evidence for association of the cloned liver growth hormone receptor with a tyrosine kinase

    DEFF Research Database (Denmark)

    Wang, X; Uhler, M D; Billestrup, N

    1992-01-01

    in a variety of cell types. The finding that the level of phosphorylation of GH receptor appears to vary with cell type is consistent with the cloned liver GH receptor being a substrate for an associated tyrosine kinase and with the amount of such a GH receptor-associated tyrosine kinase being cell type-specific.......The ability of the cloned liver growth hormone (GH) receptor, when expressed in mammalian cell lines, to copurify with tyrosine kinase activity and be tyrosyl phosphorylated was examined. 125I-human growth hormone-GH receptor complexes isolated from COS-7 cells transiently expressing high levels...... of the cloned liver GH receptor bound to anti-phosphotyrosine antibody, suggesting that the cloned GH receptor is tyrosyl phosphorylated in vivo. GH-GH receptor complexes purified from transfected COS-7 cells using anti-GH antibody incorporated 32P when incubated with [gamma-32P]ATP, indicating association...

  1. Melanin concentrating hormone receptor 1 (MCHR1) antagonists - Still a viable approach for obesity treatment?

    DEFF Research Database (Denmark)

    Högberg, T.; Frimurer, T.M.; Sasmal, P.K.

    2012-01-01

    Obesity is a global epidemic associated with multiple severe diseases. Several pharmacotherapies have been investigated including the melanin concentrating hormone (MCH) and its receptor 1. The development of MCHR1 antagonists are described with a specific perspective on different chemotypes...

  2. (−) Arctigenin and (+) Pinoresinol Are Antagonists of the Human Thyroid Hormone Receptor β

    Science.gov (United States)

    2015-01-01

    Lignans are important biologically active dietary polyphenolic compounds. Consumption of foods that are rich in lignans is associated with positive health effects. Using modeling tools to probe the ligand-binding pockets of molecular receptors, we found that lignans have high docking affinity for the human thyroid hormone receptor β. Follow-up experimental results show that lignans (−) arctigenin and (+) pinoresinol are antagonists of the human thyroid hormone receptor β. The modeled complexes show key plausible interactions between the two ligands and important amino acid residues of the receptor. PMID:25383984

  3. Identification of intracellular domains in the growth hormone receptor involved in signal transduction

    DEFF Research Database (Denmark)

    Billestrup, N; Allevato, G; Norstedt, G

    1994-01-01

    The growth hormone (GH) receptor belongs to the GH/prolactin/cytokine super-family of receptors. The signal transduction mechanism utilized by this class of receptors remains largely unknown. In order to identify functional domains in the intracellular region of the GH receptor we generated......) for metabolic effects, a domain located in or near the proline-rich region is of importance; and (iii) for internalization, phenylalanine 346 is necessary....

  4. Molecular cloning and functional characterization of the diapause hormone receptor in the corn earworm Helicoverpa zea

    Science.gov (United States)

    The diapause hormone (DH) in the heliothine moth has shown its activity in termination of pupal diapause, while the orthology in the silkworm is known to induce embryonic diapause. In the current study, we cloned the diapause hormone receptor from the corn earworm Helicoverpa zea (HzDHr) and tested ...

  5. Detection of thyroid hormone receptor disruptors by a novel stable in vitro reporter gene assay

    NARCIS (Netherlands)

    Freitas, de J.; Cano, P.; Craig-Veit, C.; Goodson, M.L.; Furlow, J.D.; Murk, A.J.

    2011-01-01

    A stable luciferase reporter gene assay was developed based on the thyroid hormone responsive rat pituitary tumor GH3 cell line that constitutively expresses both thyroid hormone receptor isoforms. Stable transfection of the pGL4CP-SV40-2xtaDR4 construct into the GH3 cells resulted in a highly

  6. Adipokinetic hormones and their G protein-coupled receptors emerged in Lophotrochozoa

    DEFF Research Database (Denmark)

    Li, Shizhong; Hauser, Frank; Skadborg, Signe K.

    2016-01-01

    the neuropeptide systems used by proto- or deuterostomes. An exception, however, are members of the gonadotropin-releasing hormone (GnRH) receptor superfamily, which occur in both evolutionary lineages, where GnRHs are the ligands in Deuterostomia and GnRH-like peptides, adipokinetic hormone (AKH), corazonin...

  7. Receptor dysfunction and hormone resistance in human diseases--a review.

    Science.gov (United States)

    Macaron, C; Famuyiwa, O

    1978-01-01

    Studies of the hormone-receptor interaction have introduced a new chapter in endocrine and metabolic disorders. Receptor (R) dysfunction in human diseases, due either to an alteration in the number or affinity of the R, or to antibodies against the R, is reviewed and classified in the first part of this paper. Disorders where hormone resistance has been implicated, but where R studies are still unavailable are also presented.

  8. Alpha-nicotinic acetylcholine receptor and tobacco smoke exposure : Effects on bronchial hyperresponsiveness in children

    NARCIS (Netherlands)

    Torjussen, Tale M.; Carlsen, Karin C. Lodrup; Munthe-Kaas, Monica C.; Mowinckel, Petter; Carlsen, Kai-Hakon; Helms, Peter J.; Gerritsen, Jorrit; Whyte, Moira K.; Lenney, Warren; Undlien, Dag E.; Shianna, Kevin V.; Zhu, Guohua; Pillai, Sreekumar G.

    Background: The CHRNA 3 and 5 genes on chromosome 15 encode the alpha subunits of the nicotinic acetylcholine receptor, mediating airway cholinergic activity. Polymorphisms are associated with cigarette smoking, chronic obstructive pulmonary disease, and lung cancer. Aims: To determine possible

  9. Conditional expression of constitutively active estrogen receptor {alpha} in chondrocytes impairs longitudinal bone growth in mice

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Kazuhiro [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Tsukui, Tohru [Experimental Animal Laboratory, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Imazawa, Yukiko; Horie-Inoue, Kuniko [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Inoue, Satoshi, E-mail: INOUE-GER@h.u-tokyo.ac.jp [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan); Department of Anti-Aging Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan)

    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 active 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.

  10. Dual Modulators of GABA-A and Alpha 7 Nicotinic Receptors for Treating Autism

    Science.gov (United States)

    2015-10-01

    AWARD NUMBER: W81XWH-13-1-0144 TITLE: Dual Modulators of GABA-A and Alpha 7 Nicotinic Receptors for Treating Autism PRINCIPAL INVESTIGATOR...SUBTITLE 5a. CONTRACT NUMBER Dual Modulators of GABA-A and Alpha 7 Nicotinic Receptors for Treating Autism 5b. GRANT NUMBER W81XWH-13-1-0144 5c...ABSTRACT Autism spectrum disorder (ASD) is a polygenic signaling disorder that may result, in part, from an imbalance in excitatory and inhibitory

  11. Alpha-Melanocyte Stimulating Hormone Protects against Cytokine-Induced Barrier Damage in Caco-2 Intestinal Epithelial Monolayers.

    Directory of Open Access Journals (Sweden)

    Judit Váradi

    Full Text Available Alpha-melanocyte-stimulating hormone (α-MSH is a potent anti-inflammatory peptide with cytoprotective effect in various tissues. The present investigation demonstrates the ability of α-MSH to interact with intestinal epithelial cell monolayers and mitigate inflammatory processes of the epithelial barrier. The protective effect of α-MSH was studied on Caco-2 human intestinal epithelial monolayers, which were disrupted by exposure to tumor necrosis factor-α and interleukin-1β. The barrier integrity was assessed by measuring transepithelial electric resistance (TEER and permeability for marker molecules. Caco-2 monolayers were evaluated by immunohistochemistry for expression of melanocortin-1 receptor and tight junction proteins ZO-1 and claudin-4. The activation of nuclear factor kappa beta (NF-κB was detected by fluorescence microscopy and inflammatory cytokine expression was assessed by flow cytometric bead array cytokine assay. Exposure of Caco-2 monolayers to proinflammatory cytokines lowered TEER and increased permeability for fluorescein and albumin, which was accompanied by changes in ZO-1 and claudin-4 immunostaining. α-MSH was able to prevent inflammation-associated decrease of TEER in a dose-dependent manner and reduce the increased permeability for paracellular marker fluorescein. Further immunohistochemistry analysis revealed proinflammatory cytokine induced translocation of the NF-κB p65 subunit into Caco-2 cell nuclei, which was inhibited by α-MSH. As a result the IL-6 and IL-8 production of Caco-2 monolayers were also decreased with different patterns by the addition of α-MSH to the culture medium. In conclusion, Caco-2 cells showed a positive immunostaining for melanocortin-1 receptor and α-MSH protected Caco-2 cells against inflammatory barrier dysfunction and inflammatory activation induced by tumor necrosis factor-α and interleukin-1β cytokines.

  12. Bioaccumulation of the synthetic hormone 17alpha-ethinylestradiol in the benthic invertebrates Chironomus tentans and Hyalella azteca.

    Science.gov (United States)

    Dussault, Eve B; Balakrishnan, Vimal K; Borgmann, Uwe; Solomon, Keith R; Sibley, Paul K

    2009-09-01

    The present study investigated the bioaccumulation of the synthetic hormone 17alpha-ethinylestradiol (EE2) in the benthic invertebrates Chironomus tentans and Hyalella azteca, in water-only and spiked sediment assays. Water and sediment residue analysis was performed by LC/MS-MS, while biota extracts were analyzed using both LC/MS-MS and a recombinant yeast estrogen receptor assay. At the lowest exposure concentration, C. tentans accumulated less EE2 than H. azteca in the water-only assays (p=0.0004), but due to different slopes, this difference subsided with increasing concentrations; at the exposure concentration of 1mg/L, C. tentans had a greater body burden than H. azteca (p=0.02). In spiked sediments, C. tentans had the greatest EE2 accumulation (1.2+/-0.14 vs. 0.5+/-0.05 microg/gdw, n=4). Measurements in H. azteca indicated a negligible contribution from the sediments to the uptake of EE2 in this species. These differences were likely due to differences in the behavior and life history of the two species (epibenthic vs. endobenthic). Water-only bioaccumulation factors (BAFs) calculated at the lowest exposure concentration were significantly smaller in C. tentans than in H. azteca (31 vs. 142, respectively; pazteca (0.8 vs. 0.3; p<0.0001). Extracts of the exposed animals caused a response in a recombinant yeast estrogen receptor assay, thus confirming the estrogenic activity of the samples, presumably from EE2 and its estrogenic metabolites. The results of the present study suggest that consumption of invertebrate food items could provide an additional source of exposure to estrogenic substances in vertebrate predators.

  13. Alpha-Melanocyte Stimulating Hormone Protects against Cytokine-Induced Barrier Damage in Caco-2 Intestinal Epithelial Monolayers.

    Science.gov (United States)

    Váradi, Judit; Harazin, András; Fenyvesi, Ferenc; Réti-Nagy, Katalin; Gogolák, Péter; Vámosi, György; Bácskay, Ildikó; Fehér, Pálma; Ujhelyi, Zoltán; Vasvári, Gábor; Róka, Eszter; Haines, David; Deli, Mária A; Vecsernyés, Miklós

    2017-01-01

    Alpha-melanocyte-stimulating hormone (α-MSH) is a potent anti-inflammatory peptide with cytoprotective effect in various tissues. The present investigation demonstrates the ability of α-MSH to interact with intestinal epithelial cell monolayers and mitigate inflammatory processes of the epithelial barrier. The protective effect of α-MSH was studied on Caco-2 human intestinal epithelial monolayers, which were disrupted by exposure to tumor necrosis factor-α and interleukin-1β. The barrier integrity was assessed by measuring transepithelial electric resistance (TEER) and permeability for marker molecules. Caco-2 monolayers were evaluated by immunohistochemistry for expression of melanocortin-1 receptor and tight junction proteins ZO-1 and claudin-4. The activation of nuclear factor kappa beta (NF-κB) was detected by fluorescence microscopy and inflammatory cytokine expression was assessed by flow cytometric bead array cytokine assay. Exposure of Caco-2 monolayers to proinflammatory cytokines lowered TEER and increased permeability for fluorescein and albumin, which was accompanied by changes in ZO-1 and claudin-4 immunostaining. α-MSH was able to prevent inflammation-associated decrease of TEER in a dose-dependent manner and reduce the increased permeability for paracellular marker fluorescein. Further immunohistochemistry analysis revealed proinflammatory cytokine induced translocation of the NF-κB p65 subunit into Caco-2 cell nuclei, which was inhibited by α-MSH. As a result the IL-6 and IL-8 production of Caco-2 monolayers were also decreased with different patterns by the addition of α-MSH to the culture medium. In conclusion, Caco-2 cells showed a positive immunostaining for melanocortin-1 receptor and α-MSH protected Caco-2 cells against inflammatory barrier dysfunction and inflammatory activation induced by tumor necrosis factor-α and interleukin-1β cytokines.

  14. Regulation and binding of pregnane X receptor by nuclear receptor corepressor silencing mediator of retinoid and thyroid hormone receptors (SMRT).

    Science.gov (United States)

    Johnson, David R; Li, Chia-Wei; Chen, Liuh-Yow; Ghosh, Jagadish C; Chen, J Don

    2006-01-01

    The pregnane X receptor (PXR) is an orphan nuclear receptor predominantly expressed in liver and intestine. PXR coordinates hepatic responses to prevent liver injury induced by environmental toxins. PXR activates cytochrome P450 3A4 gene expression upon binding to rifampicin (Rif) and clotrimazole (CTZ) by recruiting transcriptional coactivators. It remains unclear whether and how PXR regulates gene expression in the absence of ligand. In this study, we analyzed interactions between PXR and the silencing mediator of retinoid and thyroid hormone receptors (SMRT) and determined the role of SMRT in regulating PXR activity. We show that SMRT interacts with PXR in glutathione S-transferase pull-down, yeast two-hybrid, and mammalian two-hybrid assays. The interaction is mediated through the ligand-binding domain of PXR and the SMRTs' nuclear receptor-interacting domain 2. The PXR-SMRT interaction is sensitive to species-specific ligands, and Rif causes an exchange of the corepressor SMRT with the p160 coactivator known as receptor-associated coactivator 3 (RAC3). Deletion of the PXR's activation function 2 helix enhances SMRT binding and abolishes ligand-dependent dissociation of SMRT. Coexpression of PXR with SMRT results in colocalization at discrete nuclear foci. Finally, transient transfection assays show that overexpression of SMRT inhibits PXR's transactivation of the Cyp3A4 promoter, whereas silencing of SMRT enhances the reporter expression. Taken together, our results suggest that the corepressor SMRT may bind to and regulate the transcriptional activity of PXR.

  15. Effects of 17{alpha}-ethynylestradiol on hormonal responses and xenobiotic biotransformation system of Atlantic salmon (Salmo salar)

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, Anne S. [Department of Biology, Norwegian University of Science and Technology (NTNU), Hogskoleringen 5, 7491 Trondheim (Norway); Arukwe, Augustine [Department of Biology, Norwegian University of Science and Technology (NTNU), Hogskoleringen 5, 7491 Trondheim (Norway)], E-mail: arukwe@bio.ntnu.no

    2007-11-30

    Pharmaceuticals are ubiquitous pollutants in the aquatic environment where their potential effects on non-target species like fish has only recently become subject of systematic investigations. In the present study, experiments were undertaken to examine the effects of a synthetic pharmaceutical endocrine disruptor, ethynylestradiol (EE2), given in water at 5 or 50 ng/L and sampled at days 0 (control), 3 and 7 after exposure, on hepatic phase I and II biotransformation and hormonal pathways of juvenile salmon using quantitative (real-time) polymerase chain reaction (qPCR), Vtg ELISA and 7-ethoxyresorufin O-deethylase (EROD) catalytic activity. Our data show that EE2 produced time- and concentration-specific modulation of estrogen receptor isoforms (ER{alpha}, ER{beta}) and androgen receptor-{beta} (AR{beta}). EE2 produced a concentration-specific induction of vitellogenin (Vtg) and zona radiata protein (Zr-protein) at day 3 after exposure. At day 7, Vtg and Zr-protein mRNA (and plasma Vtg protein) expression were significantly decreased in the group given 5 ng EE2/L, compared to dimethyl sulfoxide (DMSO) control group. In the xenobiotic biotransformation pathway, EE2 produced a significant increase of aryl hydrocarbon receptor-{alpha} (AhR{alpha}) at day 3 in the group given 5 ng EE2/L and AhR{beta} was decreased at the same concentration at day 7. While CYP3A was not significantly affected by EE2 exposure, the CYP1A1, AhR nuclear translocator (Arnt) and AhR repressor (AhRR) mRNA showed an apparent EE2 concentration and time-dependent decrease. The expression of uridine diphosphoglucuronosyl transferase (UGT) and glutathione S-transferase class pi-like (GSTpi-like) mRNA were decreased after exposure to 50 ng EE2/L at both day 3 and 7 after exposure. The effect of EE2 on the CYP1A1 gene expressions paralleled effect on EROD and AhRR mRNA, suggesting a direct role of EE2 in controlling cellular detoxification machinery. Interestingly, the carrier vehicle, DMSO

  16. Growth hormone receptors in cultured adipocytes: a model to study receptor regulation.

    Science.gov (United States)

    Roupas, P; Herington, A C

    1986-09-01

    Acutely isolated rat adipocytes have been maintained in primary culture for several days and the effects of culture on the kinetics of 125I-human growth hormone (hGH) binding to adipocytes have been determined. A marked increase (500-1000%) in specific binding of 125I-hGH was observed over the first 3 days of culture--acutely isolated adipocytes (5.5 +/- 1.4%, mean +/- SE, n = 47) compared to 3-day cultured adipocytes (48 +/- 7%, mean +/- SE, n = 8). Specific binding of 125I-hGH to both acutely isolated and cultured adipocytes was dependent on incubation time and temperature (equilibrium being reached in 1 h at 37 degrees C and 2 h at 22 degrees C). Binding was reversible (t1/2 approximately 1.5 h). Scatchard analysis revealed linear plots and showed that the increase in binding during culture was due to an increase in the number of receptors per cell (approximately 20 000 to approximately 170 000) with little or no change in binding affinity (Ka approximately 1 X 10(9) M-1). Cycloheximide inhibited the increase in binding sites during culture suggesting a requirement for de novo protein synthesis. Addition of unlabelled hGH to the culture medium resulted in a marked down-regulation of the GH receptor by 2 days. The GH-induced decrease in receptor number was to due to receptor occupancy by exogenously added GH. The studies to date indicate that the cultured rat adipocyte should provide a useful model for a comprehensive study of the cellular mechanisms and dynamics of GH receptor regulation.

  17. Truncating Prolactin Receptor Mutations Promote Tumor Growth in Murine Estrogen Receptor-Alpha Mammary Carcinomas

    Directory of Open Access Journals (Sweden)

    Obi L. Griffith

    2016-09-01

    Full Text Available Estrogen receptor alpha-positive (ERα+ luminal tumors are the most frequent subtype of breast cancer. Stat1−/− mice develop mammary tumors that closely recapitulate the biological characteristics of this cancer subtype. To identify transforming events that contribute to tumorigenesis, we performed whole genome sequencing of Stat1−/− primary mammary tumors and matched normal tissues. This investigation identified somatic truncating mutations affecting the prolactin receptor (PRLR in all tumor and no normal samples. Targeted sequencing confirmed the presence of these mutations in precancerous lesions, indicating that this is an early event in tumorigenesis. Functional evaluation of these heterozygous mutations in Stat1−/− mouse embryonic fibroblasts showed that co-expression of truncated and wild-type PRLR led to aberrant STAT3 and STAT5 activation downstream of the receptor, cellular transformation in vitro, and tumor formation in vivo. In conclusion, truncating mutations of PRLR promote tumor growth in a model of human ERα+ breast cancer and warrant further investigation.

  18. Truncating Prolactin Receptor Mutations Promote Tumor Growth in Murine Estrogen Receptor-Alpha Mammary Carcinomas.

    Science.gov (United States)

    Griffith, Obi L; Chan, Szeman Ruby; Griffith, Malachi; Krysiak, Kilannin; Skidmore, Zachary L; Hundal, Jasreet; Allen, Julie A; Arthur, Cora D; Runci, Daniele; Bugatti, Mattia; Miceli, Alexander P; Schmidt, Heather; Trani, Lee; Kanchi, Krishna-Latha; Miller, Christopher A; Larson, David E; Fulton, Robert S; Vermi, William; Wilson, Richard K; Schreiber, Robert D; Mardis, Elaine R

    2016-09-27

    Estrogen receptor alpha-positive (ERα+) luminal tumors are the most frequent subtype of breast cancer. Stat1(-/-) mice develop mammary tumors that closely recapitulate the biological characteristics of this cancer subtype. To identify transforming events that contribute to tumorigenesis, we performed whole genome sequencing of Stat1(-/-) primary mammary tumors and matched normal tissues. This investigation identified somatic truncating mutations affecting the prolactin receptor (PRLR) in all tumor and no normal samples. Targeted sequencing confirmed the presence of these mutations in precancerous lesions, indicating that this is an early event in tumorigenesis. Functional evaluation of these heterozygous mutations in Stat1(-/-) mouse embryonic fibroblasts showed that co-expression of truncated and wild-type PRLR led to aberrant STAT3 and STAT5 activation downstream of the receptor, cellular transformation in vitro, and tumor formation in vivo. In conclusion, truncating mutations of PRLR promote tumor growth in a model of human ERα+ breast cancer and warrant further investigation. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  19. Reductions in hepatic vitellogenin and estrogen receptor alpha expression by sediments from an agriculturally impacted waterway.

    Science.gov (United States)

    Sellin, Marlo K; Snow, Daniel D; Kolok, Alan S

    2010-01-31

    Previous studies have reported alterations in the endocrine function of fathead minnows (Pimephales promelas) collected and deployed in the Elkhorn River. The goal of the current study was to determine whether sediment from the Elkhorn River watershed could act as a source of endocrine-active compounds. To accomplish this, four aquaria containing sexually mature fathead minnows and polar organic chemical integrative samplers (POCIS) were established. The aquaria contained either: (1) laboratory water only, (2) Elkhorn River water only, (3) laboratory water and Elkhorn River sediment or (4) Elkhorn River water and Elkhorn River sediment. Steroid hormones were not detected in the extracts of POCIS or sediment. Pesticides were detected in POCIS extracts from tanks containing Elkhorn River water, but were not detected in the extracts of sediment or POCIS suspended in the tank containing laboratory water and Elkhorn River sediment suggesting that sediments do not act as a significant source of the 14 steroid hormones or 24 pesticides that were analyzed for in the current study. The hepatic mRNA expression of vitellogenin (vtg) and estrogen receptor alpha (ERalpha) in fathead minnows from each group was assessed. Female minnows exposed simultaneously to sediment and water collected from the Elkhorn River experienced defeminization as indicated by significant reductions in both vtg and ERalpha expression. Significant reductions in vtg mRNA expression were also observed in females exposed to laboratory water and Elkhorn River sediment, but not in females exposed to Elkhorn River water only. This finding suggests that exposures to sediments, rather than water, collected from the Elkhorn River lead to the defeminization of females. However, the compound(s) responsible for this effect have yet to be determined. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  20. A {sup 99m}Tc(CO){sub 3}-labeled pyrazolyl-{alpha}-melanocyte-stimulating hormone analog conjugate for melanoma targeting

    Energy Technology Data Exchange (ETDEWEB)

    Raposinho, Paula D.; Correia, Joao D.G.; Alves, Susana [Departamento de Quimica, ITN, Estrada Nacional 10, 2686-953 Sacavem (Portugal); Botelho, Maria F.; Santos, Ana C. [Instituto de Biofisica/Biomatematica, IBILI-Faculdade de Medicina de Coimbra, 300-548 Coimbra (Portugal); Santos, Isabel [Departamento de Quimica, ITN, Estrada Nacional 10, 2686-953 Sacavem (Portugal)], E-mail: isantos@itn.pt

    2008-01-15

    Melanoma primary tumors can be, in most cases, removed surgically, whereas there is no satisfactory treatment for metastatic melanoma, being almost always lethal at this stage. Therefore, early detection of primary melanoma tumors is essential. The finding that melanocortin-1 receptor (MC1R) is overexpressed in isolated melanoma cells and melanoma tissues led to the radiolabeling of several {alpha}-melanocyte-stimulating hormone ({alpha}-MSH) analogs for early detection and treatment of melanoma. We have coupled the {alpha}-MSH analog Ac-Nle-Asp-His-D-Phe-Arg-Trp-Gly-Lys-NH{sub 2}, through the {epsilon}-amino group of Lys{sup 11}, to a pyrazolyl-containing chelator (pz). The resulting pz-{alpha}-MSH analog reacted with the fac-[{sup 99m}Tc(CO){sub 3}]{sup +} moiety, giving [Ac-Nle{sup 4},Asp{sup 5},D-Phe{sup 7},Lys{sup 11}(pz-{sup 99m}Tc(CO){sub 3})]{alpha}-MSH{sub 4-11} in high yield, high specific activity and high radiochemical purity. This radioconjugate, which presents remarkable stability in vitro, exhibited time- and temperature-dependent internalization (4 h at 37{sup o}C; 56.7% maximum internalization) and high cellular retention (only 38% was released from the cell after 5 h) in murine melanoma B16F1 cells. A significant tumor uptake [4.2{+-}0.9%ID/g, at 4 h postinjection (p.i.)] was also obtained in melanoma-bearing C57BL6 mice. The in vivo affinity and specificity of the radioconjugate to MC1R were demonstrated by receptor-blocking studies with the potent NDP-MSH agonist (63.5% reduction in tumor uptake at 4 h p.i.)

  1. Expression of transforming growth factor-alpha and epidermal growth factor receptor in gastrointestinal stromal tumours.

    Science.gov (United States)

    Cai, Y C; Jiang, Z; Vittimberga, F; Xu, X; Savas, L; Woda, B; Callery, M; Banner, B

    1999-08-01

    Activation of epidermal growth factor receptor (EGFR) is associated with cell growth and transformation. Both transforming growth factor-alpha (TGF-alpha) and epidermal growth factor bind to and activate EGFR. We studied the expression of TGF-alpha and two EGFRs (HER-1 and HER-2) in gastrointestinal stromal tumours (GISTs) of the stomach (n = 9) and small intestine (n = 6) using standard immunostaining techniques in paraffin-embedded sections. Most GISTs expressed TGF-alpha, and a few expressed HER-1. All HER-1-positive tumours expressed TGF-alpha. These results suggest that a TGF-alpha/EGFR autocrine loop is present in GIST and that TGF-alpha promotes proliferation of GIST tumour cells through its interaction with HER-1 in at least some GISTs. This is the first description of an autocrine loop in GIST. In contrast, HER-2 is not expressed in any GIST.

  2. Cognitive improvement by activation of alpha7 nicotinic acetylcholine receptors: from animal models to human pathophysiology

    DEFF Research Database (Denmark)

    Thomsen, Morten S; Hansen, Henrik H; Timmerman, Daniel B

    2010-01-01

    Agonists and positive allosteric modulators of the alpha(7) nicotinic acetylcholine receptor (nAChR) are currently being developed for the treatment of cognitive disturbances in patients with schizophrenia or Alzheimer's disease. This review describes the neurobiological properties of the alpha n......AChR and the cognitive effects of alpha(7) nAChR activation, focusing on the translational aspects in the development of these drugs. The functional properties and anatomical localization of the alpha(7) nAChR makes it well suited to modulate cognitive function. Accordingly, systemic administration of alpha(7) n......AChR agonists improves learning, memory, and attentional function in variety of animal models, and pro-cognitive effects of alpha(7) nAChR agonists have recently been demonstrated in patients with schizophrenia or Alzheimer's disease. The alpha(7) nAChR desensitizes rapidly in vitro, and this has been a major...

  3. [Drug therapy of benign prostatic hyperplasia. Is combination therapy with 5 alpha-reductase inhibitors and alpha-receptor blockers effective?].

    Science.gov (United States)

    Horninger, W; Bartsch, G

    2002-09-01

    5 alpha-reductase inhibitors and alpha 1-receptor blockers are the two main drug therapies used in the management of symptomatic benign prostatic hyperplasia. As alpha-reductase inhibitors and alpha 1-receptor blockers act through different mechanisms, a combination of the two agents might be promising. The potential benefits of combination therapy with selective alpha 1-receptor blockers and finasteride, a 5 alpha-reductase inhibitor, are currently being evaluated in several placebo-controlled prospective multicenter studies (VA Study, ALFIN Study, PREDICT Study, and MTOPS Study). The data from these studies available so far demonstrate a statistically significant benefit for the study groups receiving alpha 1-receptor blockers and combination therapy vs placebo and finasteride monotherapy in terms of symptom scores and peak urine flow rates. However, none of the studies yielded a statistically significant advantage of combination therapy over treatment with alpha 1-receptor blockers. These results should be interpreted with reference to the prostatic volume, which in the studies mentioned above was relatively low. From the results of all these studies, it can be concluded that in symptomatic patients with prostate volumes of up to 40-45 ml a combination of 5 alpha-reductase inhibitors with alpha 1-receptor blockers does not appear to provide any benefit. Yet, it can be assumed that in symptomatic patients with prostate volumes of more than 60 ml combination therapy may indeed prove more effective.

  4. Estrogen treatment decreases matrix metalloproteinase (MMP)-9 in autoimmune demyelinating disease through estrogen receptor alpha (ERalpha).

    Science.gov (United States)

    Gold, Stefan M; Sasidhar, Manda V; Morales, Laurie B; Du, Sienmi; Sicotte, Nancy L; Tiwari-Woodruff, Seema K; Voskuhl, Rhonda R

    2009-10-01

    Matrix metalloproteinases (MMPs) have a crucial function in migration of inflammatory cells into the central nervous system (CNS). Levels of MMP-9 are elevated in multiple sclerosis (MS) and predict the occurrence of new active lesions on magnetic resonance imaging (MRI). This translational study aims to determine whether in vivo treatment with the pregnancy hormone estriol affects MMP-9 levels from immune cells in patients with MS and mice with experimental autoimmune encephalomyelitis (EAE). Peripheral blood mononuclear cells (PBMCs) collected from three female MS patients treated with estriol and splenocytes from EAE mice treated with estriol, estrogen receptor (ER) alpha ligand, ERbeta ligand or vehicle were stimulated ex vivo and analyzed for levels of MMP-9. Markers of CNS infiltration were assessed using MRI in patients and immunohistochemistry in mice. Supernatants from PBMCs obtained during estriol treatment in female MS patients showed significantly decreased MMP-9 compared with pretreatment. Decreases in MMP-9 coincided with a decrease in enhancing lesion volume on MRI. Estriol treatment of mice with EAE reduced MMP-9 in supernatants from autoantigen-stimulated splenocytes, coinciding with decreased CNS infiltration by T cells and monocytes. Experiments with selective ER ligands showed that this effect was mediated through ERalpha. In conclusion, estriol acting through ERalpha to reduce MMP-9 from immune cells is one mechanism potentially underlying the estriol-mediated reduction in enhancing lesions in MS and inflammatory lesions in EAE.

  5. Pentadecapeptide BPC 157 Enhances the Growth Hormone Receptor Expression in Tendon Fibroblasts

    Directory of Open Access Journals (Sweden)

    Chung-Hsun Chang

    2014-11-01

    Full Text Available BPC 157, a pentadecapeptide derived from human gastric juice, has been demonstrated to promote the healing of different tissues, including skin, muscle, bone, ligament and tendon in many animal studies. However, the underlying mechanism has not been fully clarified. The present study aimed to explore the effect of BPC 157 on tendon fibroblasts isolated from Achilles tendon of male Sprague-Dawley rat. From the result of cDNA microarray analysis, growth hormone receptor was revealed as one of the most abundantly up-regulated genes in tendon fibroblasts by BPC 157. BPC 157 dose- and time-dependently increased the expression of growth hormone receptor in tendon fibroblasts at both the mRNA and protein levels as measured by RT/real-time PCR and Western blot, respectively. The addition of growth hormone to BPC 157-treated tendon fibroblasts dose- and time-dependently increased the cell proliferation as determined by MTT assay and PCNA expression by RT/real-time PCR. Janus kinase 2, the downstream signal pathway of growth hormone receptor, was activated time-dependently by stimulating the BPC 157-treated tendon fibroblasts with growth hormone. In conclusion, the BPC 157-induced increase of growth hormone receptor in tendon fibroblasts may potentiate the proliferation-promoting effect of growth hormone and contribute to the healing of tendon.

  6. Pentadecapeptide BPC 157 enhances the growth hormone receptor expression in tendon fibroblasts.

    Science.gov (United States)

    Chang, Chung-Hsun; Tsai, Wen-Chung; Hsu, Ya-Hui; Pang, Jong-Hwei Su

    2014-11-19

    BPC 157, a pentadecapeptide derived from human gastric juice, has been demonstrated to promote the healing of different tissues, including skin, muscle, bone, ligament and tendon in many animal studies. However, the underlying mechanism has not been fully clarified. The present study aimed to explore the effect of BPC 157 on tendon fibroblasts isolated from Achilles tendon of male Sprague-Dawley rat. From the result of cDNA microarray analysis, growth hormone receptor was revealed as one of the most abundantly up-regulated genes in tendon fibroblasts by BPC 157. BPC 157 dose- and time-dependently increased the expression of growth hormone receptor in tendon fibroblasts at both the mRNA and protein levels as measured by RT/real-time PCR and Western blot, respectively. The addition of growth hormone to BPC 157-treated tendon fibroblasts dose- and time-dependently increased the cell proliferation as determined by MTT assay and PCNA expression by RT/real-time PCR. Janus kinase 2, the downstream signal pathway of growth hormone receptor, was activated time-dependently by stimulating the BPC 157-treated tendon fibroblasts with growth hormone. In conclusion, the BPC 157-induced increase of growth hormone receptor in tendon fibroblasts may potentiate the proliferation-promoting effect of growth hormone and contribute to the healing of tendon.

  7. Canine narcolepsy is associated with an elevated number of alpha 2-receptors in the locus coeruleus.

    Science.gov (United States)

    Fruhstorfer, B; Mignot, E; Bowersox, S; Nishino, S; Dement, W C; Guilleminault, C

    1989-10-23

    alpha 2-Receptors in the canine brain were pharmacologically characterized using [3H]yohimbine binding. Competition studies revealed a single class of binding sites in frontal cortex but two distinct subtypes in nucleus caudatus. The role of central alpha 2-receptors in narcolepsy was investigated in 5 normal and 5 narcoleptic Doberman pinschers. Scatchard analysis of [3H]yohimbine binding in different brain areas revealed an increase in the number of alpha 2-binding sites limited to the locus coeruleus. This suggests that altered autoinhibition of norepinephrine release may be associated with the narcoleptic symptomatology.

  8. Models for the binding of amiodarone to the thyroid hormone receptor

    Science.gov (United States)

    Chalmers, David K.; Munro, Sharon L. A.; Iskander, Magdy N.; Craik, David J.

    1992-02-01

    The antiarrhythmic drug amiodarone has recently been characterized as the first known thyroid hormone antagonist. Its mode of interaction with the thyroid hormone receptor is therefore of interest. A computational analysis of the conformational flexibility of amiodarone using molecular mechanics and the semiempirical molecular orbital method AM1 has been performed. The molecular mechanics studies show that the low-energy conformations of the benzoylbenzofuran portion of amiodarone can be grouped into 4 distinct classes, while the diethylaminoethoxy side chain is extremely flexible. Conformers representative of the 4 low-energy classes were fitted to an extended thyroid hormone receptor model. Four independent modes in which amiodarone could bind to the thyroid hormone receptor site were evaluated.

  9. Expression and role of gonadotropin-releasing hormone 2 and its receptor in mammals

    Science.gov (United States)

    Gonadotropin-releasing hormone (GnRH1) and its receptor (GnRHR1) drive mammalian reproduction via regulation of the gonadotropins. Yet, a second form of GnRH (GnRH2) and its receptor (GnRHR2) also exist in some mammals. GnRH2 has been completely conserved throughout 500 million years of evolution, s...

  10. The role of palmitoylation in functional expression of nicotinic alpha7 receptors.

    Science.gov (United States)

    Drisdel, Renaldo C; Manzana, Ehrine; Green, William N

    2004-11-17

    Neuronal alpha-bungarotoxin receptors (BgtRs) are nicotinic receptors that require as yet unidentified post-translational modifications to achieve functional expression. In this study, we examined the role of protein palmitoylation in BgtR expression. BgtR alpha7 subunits are highly palmitoylated in neurons from brain and other cells capable of BgtR expression, such as pheochromocytoma 12 (PC12) cells. In PC12 cells, alpha7 subunits are palmitoylated with a stoichiometry of approximately one palmitate per subunit, and inhibition of palmitoylation blocks BgtR expression. In cells incapable of BgtR expression, such as human embryonic kidney cells, alpha7 subunits are not significantly palmitoylated. However, in these same cells, chimeric subunits with the N-terminal half of alpha7 fused to the C-terminal half of serotonin-3A receptor (alpha7/5-HT3A) subunits form functional BgtRs that are palmitoylated to an extent similar to that of BgtRalpha7 subunits in PC12 cells. Palmitoylation of PC12 and alpha7/5-HT3A BgtRs occurred during assembly in the endoplasmic reticulum (ER). In conclusion, our data indicate a function for protein palmitoylation in which palmitoylation of assembling alpha7 subunits in the ER has a role in the formation of functional BgtRs.

  11. Identifying neuropeptide and protein hormone receptors in Drosophila melanogaster by exploiting genomic data

    DEFF Research Database (Denmark)

    Hauser, Frank; Williamson, Michael; Cazzamali, Giuseppe

    2006-01-01

    Most neuropeptide and protein hormone receptors belong to the large superfamily of G-protein-coupled receptors (GPCRs). These cell membrane proteins steer many important processes such as development, reproduction, homeostasis and behaviour when activated by their corresponding ligands. The first...... insect genome, that of the fruitfly Drosophila melanogaster, was sequenced in 2000, and about 200 GPCRs have been annnotated in this model insect. About 50 of these receptors were predicted to have neuropeptides or protein hormones as their ligands. Since 2000, the cDNAs of most of these candidate...

  12. Autoradiographic analysis of alpha 1-noradrenergic receptors in the human brain postmortem. Effect of suicide

    Energy Technology Data Exchange (ETDEWEB)

    Gross-Isseroff, R.; Dillon, K.A.; Fieldust, S.J.; Biegon, A. (Weizmann Institute of Science, Rehovot (Israel))

    1990-11-01

    In vitro quantitative autoradiography of alpha 1-noradrenergic receptors, using tritiated prazosin as a ligand, was performed on 24 human brains postmortem. Twelve brains were obtained from suicide victims and 12 from matched controls. We found significant lower binding to alpha 1 receptors in several brain regions of the suicide group as compared with matched controls. This decrease in receptor density was evident in portions of the prefrontal cortex, as well as the temporal cortex and in the caudate nucleus. Age, sex, presence of alcohol, and time of death to autopsy did not affect prazosin binding, in our sample, as measured by autoradiography.

  13. Molecular cloning and functional characterization of the human platelet-derived growth factor alpha receptor gene promoter

    NARCIS (Netherlands)

    Afink, G. B.; Nistér, M.; Stassen, B. H.; Joosten, P. H.; Rademakers, P. J.; Bongcam-Rudloff, E.; van Zoelen, E. J.; Mosselman, S.

    1995-01-01

    Expression of the platelet-derived growth factor alpha receptor (PDGF alpha R) is strictly regulated during mammalian development and tumorigenesis. The molecular mechanisms involved in the specific regulation of PDGF alpha R expression are unknown, but transcriptional regulation of the PDGF alpha R

  14. [Bioactivity of thyroid hormones. Clinical significance of membrane transporters, deiodinases and nuclear receptors].

    Science.gov (United States)

    Solís, Juan Carlos; Orozco, Aurea; García, Carlota; Robles-Osorio, Ludivina; Valverde, Carlos

    2011-01-01

    The study of the different factors regulating the bioactivity of thyroid hormones is of utmost relevance for an adequate understanding of the glandular pathophysiology. These factors must be considered by the clinician in order to achieve a successful diagnosis and treatment of glandular diseases. Among the factors regulating bioactivity of thyroid hormones are the following: A) Plasmatic membrane hormone transporters, which tissue-specific expression is responsible for the cellular uptake of hormones, B) A set of deiodinating enzymes which activate or inactivate intracellular thyroid hormone, and C) Nuclear receptors which are responsible for the different cellular responses at the transcriptional level. This review compiles analysis and discusses the most recent findings regarding the regulation of thyroid hormone bioactivity, as well as the clinical relevance of different polymorphisms and mutations currently described for membrane transporters and deiodinases. In addition, the main issues and present and future study areas are identified.

  15. Arterial calcifications and increased expression of vitamin D receptor targets in mice lacking TIF1alpha.

    Science.gov (United States)

    Ignat, Mihaela; Teletin, Marius; Tisserand, Johan; Khetchoumian, Konstantin; Dennefeld, Christine; Chambon, Pierre; Losson, Régine; Mark, Manuel

    2008-02-19

    Calcification of arteries is a major risk factor for cardiovascular mortality in humans. Using genetic approaches, we demonstrate here that the transcriptional intermediary factor 1alpha (TIF1alpha), recently shown to function as a tumor suppressor in murine hepatocytes, also participates in a molecular cascade that prevents calcifications in arterioles and medium-sized arteries. We further provide genetic evidence that this function of TIF1alpha is not exerted in hepatocytes. The sites of ectopic calcifications in mutant mice lacking TIF1alpha resemble those seen in mice carrying an activating mutation of the calcium sensor receptor (Casr) gene and, in TIF1alpha-deficient kidneys, Casr expression is increased together with that of many other vitamin D receptor (VDR) direct target genes, namely Car2, Cyp24a1, Trpv5, Trpv6, Calb1, S100g, Pthlh, and Spp1. Thus, our data indicate that TIF1alpha represses the VDR pathway in kidney and suggest that an up-regulation of Casr expression in this organ could account for ectopic calcifications generated upon TIF1alpha deficiency. Interestingly, the calcifying arteriopathy of TIF1alpha-null mutant mice shares features with the human age-related Mönckeberg's disease and, overall, the TIF1alpha-null mutant pathological phenotype supports the hypothesis that aging is promoted by increased activity of the vitamin D signaling pathway.

  16. Hormone-receptor expression and ovarian cancer survival

    DEFF Research Database (Denmark)

    Sieh, Weiva; Köbel, Martin; Longacre, Teri A

    2013-01-01

    Few biomarkers of ovarian cancer prognosis have been established, partly because subtype-specific associations might be obscured in studies combining all histopathological subtypes. We examined whether tumour expression of the progesterone receptor (PR) and oestrogen receptor (ER) was associated...

  17. Pattern of hormone receptors and human epidermal growth factor ...

    African Journals Online (AJOL)

    Introduction: Breast cancer is the most common cancer among women globally. With immunohistochemistry (IHC), breast cancer is classified into four groups based on IHC profile of estrogen receptor (ER)/progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2/neu) expression, positive (+) and/or ...

  18. Roles of estrogen receptors alpha and beta in differentiation of mouse sexual behavior.

    Science.gov (United States)

    Kudwa, A E; Michopoulos, V; Gatewood, J D; Rissman, E F

    2006-01-01

    Sex differences in brain and behavior are ubiquitous in sexually reproducing species. Developmental differences in circulating concentrations of gonadal steroids underlie many sexual dimorphisms. During the late embryonic and early perinatal periods, the testes produce androgens, thus, male brains are exposed to testosterone, and in situ testosterone is aromatized to estradiol. In contrast, females are not exposed to high concentrations of testosterone or estradiol until puberty. In many species, neural sex differences and sexually dimorphic behaviors in adults are initiated primarily by estradiol exposure during early development. In brain, estradiol activates two independent processes: masculinization of neural circuits and networks that are essential for expression of male-typical adult behaviors, and defeminization, the loss of the ability to display adult female-typical behaviors. Here, data for the roles of each of the known estrogen receptors (estrogen receptor alpha and estrogen receptor beta) in these two processes are reviewed. Based on work done primarily in knockout mouse models, separate roles for the two estrogen receptors are suggested. Estrogen receptor alpha is primarily involved in masculinization, while estrogen receptor beta has a major role in defeminization of sexual behaviors. In sum, estradiol can have selective effects on distinct behavioral processes via selective interactions with its two receptors, estrogen receptor alpha and estrogen receptor beta.

  19. Cognitive improvement by activation of alpha7 nicotinic acetylcholine receptors: from animal models to human pathophysiology

    DEFF Research Database (Denmark)

    Thomsen, Morten S; Hansen, Henrik H; Timmerman, Daniel B

    2010-01-01

    AChR agonists improves learning, memory, and attentional function in variety of animal models, and pro-cognitive effects of alpha(7) nAChR agonists have recently been demonstrated in patients with schizophrenia or Alzheimer's disease. The alpha(7) nAChR desensitizes rapidly in vitro, and this has been a major...... preclinical evaluation of alpha(7) nAChR activation. It is therefore important to consider the translational power of the animal models used before entering into a clinical evaluation of the pro-cognitive effects of alpha(7) nAChR activation.......Agonists and positive allosteric modulators of the alpha(7) nicotinic acetylcholine receptor (nAChR) are currently being developed for the treatment of cognitive disturbances in patients with schizophrenia or Alzheimer's disease. This review describes the neurobiological properties of the alpha n...

  20. Expression of ciliary neurotrophic factor (CNTF), CNTF receptor alpha (CNTFR-alpha) following experimental intracerebral hemorrhage in rats.

    Science.gov (United States)

    Yokota, Hiroshi; Yoshikawa, Masahide; Hirabayashi, Hidehiro; Nakase, Hiroyuki; Uranishi, Ryunosuke; Nishimura, Fumihiko; Sugie, Yuko; Ishizaka, Shigeaki; Sakaki, Toshisuke

    2005-04-04

    Ciliary neurotrophic factor (CNTF) is known as a neuro-survival factor in the developing and developed CNS, as well as in the CNS following injury. However, little is known about the expression of CNTF or that of its receptor (CNTFR-alpha) in cases of intracerebral hemorrhage (ICH). We investigated the temporal and spatial profiles of CNTF and CNTFR-alpha expression using a collagenase-induced ICH rat model. CNTF expression was up-regulated from the day following ICH induction and reached a peak level at 5 to 14 days, with increased expression observed in brain tissue surrounding the hematoma lesion and white matter structures in association with astroglial proliferation. Further, CNTFR-alpha was transiently expressed in the cerebral cortex surrounding the hematoma, with a peak at 5 days. Administration of exogenous CNTF into the lesion following initiation of ICH resulted in a prolonged expression of CNTFR-alpha on cortical neurons neighboring the hematoma. Our findings suggest differential regulation of CNTF and CNTFR-alpha, and the possibility of a therapeutic strategy using CNTF administration for ICH.

  1. Integrin alphaVbeta6 is a high-affinity receptor for coxsackievirus A9.

    Science.gov (United States)

    Heikkilä, Outi; Susi, Petri; Stanway, Glyn; Hyypiä, Timo

    2009-01-01

    Coxsackievirus A9 (CAV9), a member of the genus Enterovirus in the family Picornaviridae, possesses an integrin-binding arginine-glycine-aspartic acid (RGD) motif in the C terminus of VP1 capsid protein. CAV9 has been shown to utilize integrins alphaVbeta3 and alphaVbeta6 as primary receptors for cell attachment. While CAV9 RGD-mutants (RGE and RGDdel) are capable of infecting rhabdomyosarcoma (RD) cell line, they grow very poorly in an epithelial lung carcinoma cell line (A549). In this study, the relationships between CAV9 infectivity in A549 and RD cells, receptor expression and integrin binding were analysed. A549 cells were shown to express both integrins alphaVbeta3 and alphaVbeta6, whereas alphaVbeta6 expression was not detected on the RD cells. Native CAV9 but not RGE and RGDdel mutants bound efficiently to immobilized alphaVbeta3 and alphaVbeta6. Adhesion of CAV9 but not RGE/RGDdel to A549 cells was also significantly higher than to RD cells. In contrast, no affinity or adhesion of bacterially produced VP1 proteins to the integrins or to the cells was detected. Function-blocking antibodies against alphaV-integrins blocked CAV9 but not CAV9-RGDdel infectivity, indicating that the viruses use different internalization routes; this may explain the differential infection kinetics of CAV9 and RGDdel. In an affinity assay, soluble alphaVbeta6, but not alphaVbeta3, bound to immobilized CAV9. Similarly, only soluble alphaVbeta6 blocked virus infectivity. These data suggest that CAV9 binding to alphaVbeta6 is a high-affinity interaction, which may indicate its importance in clinical infections; this remains to be determined.

  2. Nicotinic receptor Alpha7 expression during tooth morphogenesis reveals functional pleiotropy.

    Directory of Open Access Journals (Sweden)

    Scott W Rogers

    Full Text Available The expression of nicotinic acetylcholine receptor (nAChR subtype, alpha7, was investigated in the developing teeth of mice that were modified through homologous recombination to express a bi-cistronic IRES-driven tau-enhanced green fluorescent protein (GFP; alpha7GFP or IRES-Cre (alpha7Cre. The expression of alpha7GFP was detected first in cells of the condensing mesenchyme at embryonic (E day E13.5 where it intensifies through E14.5. This expression ends abruptly at E15.5, but was again observed in ameloblasts of incisors at E16.5 or molar ameloblasts by E17.5-E18.5. This expression remains detectable until molar enamel deposition is completed or throughout life as in the constantly erupting mouse incisors. The expression of alpha7GFP also identifies all stages of innervation of the tooth organ. Ablation of the alpha7-cell lineage using a conditional alpha7Cre×ROSA26-LoxP(diphtheria toxin A strategy substantially reduced the mesenchyme and this corresponded with excessive epithelium overgrowth consistent with an instructive role by these cells during ectoderm patterning. However, alpha7knock-out (KO mice exhibited normal tooth size and shape indicating that under normal conditions alpha7 expression is dispensable to this process. The function of ameloblasts in alpha7KO mice is altered relative to controls. High resolution micro-computed tomography analysis of adult mandibular incisors revealed enamel volume of the alpha7KO was significantly reduced and the organization of enamel rods was altered relative to controls. These results demonstrate distinct and varied spatiotemporal expression of alpha7 during tooth development, and they suggest that dysfunction of this receptor would have diverse impacts upon the adult organ.

  3. T helper 17 lineage differentiation is programmed by orphan nuclear receptors ROR alpha and ROR gamma.

    Science.gov (United States)

    Yang, Xuexian O; Pappu, Bhanu P; Nurieva, Roza; Akimzhanov, Askar; Kang, Hong Soon; Chung, Yeonseok; Ma, Li; Shah, Bhavin; Panopoulos, Athanasia D; Schluns, Kimberly S; Watowich, Stephanie S; Tian, Qiang; Jetten, Anton M; Dong, Chen

    2008-01-01

    T cell functional differentiation is mediated by lineage-specific transcription factors. T helper 17 (Th17) has been recently identified as a distinct Th lineage mediating tissue inflammation. Retinoic acid receptor-related orphan receptor gamma (ROR gamma) was shown to regulate Th17 differentiation; ROR gamma deficiency, however, did not completely abolish Th17 cytokine expression. Here, we report Th17 cells highly expressed another related nuclear receptor, ROR alpha, induced by transforming growth factor-beta and interleukin-6 (IL-6), which is dependent on signal transducer and activator of transcription 3. Overexpression of ROR alpha promoted Th17 differentiation, possibly through the conserved noncoding sequence 2 in Il17-Il17f locus. ROR alpha deficiency resulted in reduced IL-17 expression in vitro and in vivo. Furthermore, ROR alpha and ROR gamma coexpression synergistically led to greater Th17 differentiation. Double deficiencies in ROR alpha and ROR gamma globally impaired Th17 generation and completely protected mice against experimental autoimmune encephalomyelitis. Therefore, Th17 differentiation is directed by two lineage-specific nuclear receptors, ROR alpha and ROR gamma.

  4. Steroid hormone receptor expression in ovarian cancer: progesterone receptor B as prognostic marker for patient survival

    Directory of Open Access Journals (Sweden)

    Lenhard Miriam

    2012-11-01

    Full Text Available Abstract Background There is partially conflicting evidence on the influence of the steroid hormones estrogen (E and progesterone (P on the development of ovarian cancer (OC. The aim of this study was to assess the expression of the receptor isoforms ER-α/-β and PR-A/-B in OC tissue and to analyze its impact on clinical and pathological features and patient outcome. Methods 155 OC patients were included who had been diagnosed and treated between 1990 and 2002. Patient characteristics, histology and follow-up data were available. ER-α/-β and PR-A/-B expression were determined by immunohistochemistry. Results OC tissue was positive for ER-α/-β in 31.4% and 60.1% and PR-A/-B in 36.2% and 33.8%, respectively. We identified significant differences in ER-β expression related to the histological subtype (p=0.041, stage (p=0.002 and grade (p=0.011 as well as PR-A and tumor stage (p=0.03. Interestingly, median receptor expression for ER-α and PR-A/-B was significantly higher in G1 vs. G2 OC. Kaplan Meier analysis revealed a good prognosis for ER-α positive (p=0.039 and PR-B positive (p Conclusion ER-α/-β and PR-A/-B are frequently expressed in OC with a certain variability relating to histological subtype, grade and stage. Univariate analysis indicated a favorable outcome for ER-α positive and PR-B positive OC, while multivariate analysis showed PR-B to be the only independent prognostic marker for patient survival. In conclusion, ER and PR receptors may be useful targets for a more individualized OC therapy.

  5. CLONING, EXPRESSION AND CHARACTERIZATION OF THE ANDROGEN RECEPTOR AND ISOLATION OF ESTROGEN RECEPTOR ALPHA FROM THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    Science.gov (United States)

    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...

  6. Genetic analysis of the estrogen-related receptor alpha and studies of association with obesity and type 2 diabetes

    DEFF Research Database (Denmark)

    Larsen, L H; Rose, C S; Sparsø, T

    2007-01-01

    The estrogen-related receptor alpha (ERRalpha or NR3B1) is a transcription factor from the nuclear receptor super-family, group III. The gene encoding ERRalpha (ESRRA) is located on chromosome 11q13, a region showing genetic linkage to body mass index and fat percentage. Through interaction with ...... with the peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha), ERRalpha regulates key enzymes involved in the beta-oxidation of fatty acids....

  7. Structural and functional divergence of growth hormone-releasing hormone receptors in early sarcopterygians: lungfish and Xenopus.

    Directory of Open Access Journals (Sweden)

    Janice K V Tam

    Full Text Available The evolutionary trajectories of growth hormone-releasing hormone (GHRH receptor remain enigmatic since the discovery of physiologically functional GHRH-GHRH receptor (GHRHR in non-mammalian vertebrates in 2007. Interestingly, subsequent studies have described the identification of a GHRHR(2 in chicken in addition to the GHRHR and the closely related paralogous receptor, PACAP-related peptide (PRP receptor (PRPR. In this article, we provide information, for the first time, on the GHRHR in sarcopterygian fish and amphibians by the cloning and characterization of GHRHRs from lungfish (P. dolloi and X. laevis. Sequence alignment and phylogenetic analyses demonstrated structural resemblance of lungfish GHRHR to their mammalian orthologs, while the X. laevis GHRHR showed the highest homology to GHRHR(2 in zebrafish and chicken. Functionally, lungfish GHRHR displayed high affinity towards GHRH in triggering intracellular cAMP and calcium accumulation, while X. laevis GHRHR(2 was able to react with both endogenous GHRH and PRP. Tissue distribution analyses showed that both lungfish GHRHR and X. laevis GHRHR(2 had the highest expression in brain, and interestingly, X. laevis(GHRHR2 also had high abundance in the reproductive organs. These findings, together with previous reports, suggest that early in the Sarcopterygii lineage, GHRHR and PRPR have already established diverged and specific affinities towards their cognate ligands. GHRHR(2, which has only been found in xenopus, zebrafish and chicken hitherto, accommodates both GHRH and PRP.

  8. Risks of unregulated use of alpha-melanocyte-stimulating hormone analogues: a review.

    Science.gov (United States)

    Habbema, Louis; Halk, Anne Berthe; Neumann, Martino; Bergman, Wilma

    2017-10-01

    Recently, the unregulated use of untested synthetic alpha-melanocyte-stimulating hormone (α-MSH) analogues, commonly known as melanotan I and II, appears to have increased. These analogues are primarily used for their tan-stimulating effects. Dermatologists see many patients in their clinic who tan. This review provides an overview of the risks of the unregulated use of these substances. Other topics discussed here include the history and safety of afamelanotide, which is the only α-MSH analogue that is approved for use in a limited number of medical indications. Although afamelanotide has been thoroughly tested and deemed safe, illegal melanotans are likely risky for several reasons. There are questions regarding the preparation, administration, and dosage of these substances. In addition to these general risks, increasing numbers of case reports indicate that the unregulated use of both melanotan I and II is associated with cutaneous complications, particularly melanocytic changes in existing moles and newly emerging (dysplastic) nevi. Four case reports have described melanomas emerging from existing moles either during or shortly after the use of melanotan. Although conclusive evidence linking these phenomena is lacking, publications have stressed the importance of awareness that melanotan is a part of a 'tanning culture' in certain subpopulations. Multiple national health organizations have issued safety warnings regarding the use of melanotan I and II. © 2017 The International Society of Dermatology.

  9. Implications of Sex Hormone Receptor Gene Expression in the Predominance of Hepatocellular Carcinoma in Males: Role of Natural Products.

    Science.gov (United States)

    Ahmed, Hanaa H; Shousha, Wafaa Gh; Shalby, Aziza B; El-Mezayen, Hatem A; Ismaiel, Nora N; Mahmoud, Nadia S

    2015-01-01

    The present study was planned to investigate the role of sex hormone receptor gene expression in the pathogenesis of hepatocellular carcinoma (HCC). Adult male Wistar rats were divided into seven groups. Group (1) was negative control. Groups (2), (5), (6), and (7) were orally administered with N-nitrosodiethylamine for the induction of HCC, then group (2) was left untreated, group (5) was orally treated with curcumin, group (6) was orally treated with carvacrol, and group (7) was intraperitoneally injected with doxorubicin, whereas groups (3) and (4) were orally administered only curcumin and carvacrol, respectively. The HCC group showed significant upregulation in the androgen receptor (AR) and the estrogen receptor-alpha (ERα) gene expression levels in the liver tissue. On the contrary, HCC groups treated with either curcumin or carvacrol showed significant downregulation in AR and ERα gene expression levels in the liver tissue. In conclusion, the obtained data highlight that both AR and ERα but not estrogen receptor-beta (ERβ) gene expression may contribute to the male prevalence of HCC induced in male rats. Interestingly, both curcumin and carvacrol were found to have a promising potency in alleviating the male predominating HCC.

  10. Thyroid hormone receptor orthologues from invertebrate species with emphasis on Schistosoma mansoni

    OpenAIRE

    Wu, Wenjie; Niles, Edward G; LoVerde, Philip T

    2007-01-01

    Abstract Background: Thyroid hormone receptors (TRs) function as molecular switches in response to thyroid hormone to regulate gene transcription. TRs were previously believed to be present only in chordates. Results: We isolated two TR genes from the Schistosoma mansoni and identified TR orthologues from other invertebrates: the platyhelminths, S. japonium and Schmidtea mediterranea, the mollusc, Lottia gigantean and the arthropod Daphnia pulex. Phylogenetic analysis of the DNA binding domai...

  11. A C-terminal fragment of Agouti-related protein increases feeding and antagonizes the effect of alpha-melanocyte stimulating hormone in vivo.

    Science.gov (United States)

    Rossi, M; Kim, M S; Morgan, D G; Small, C J; Edwards, C M; Sunter, D; Abusnana, S; Goldstone, A P; Russell, S H; Stanley, S A; Smith, D M; Yagaloff, K; Ghatei, M A; Bloom, S R

    1998-10-01

    Agouti-related protein (Agrp) is present in rat and human hypothalamus and is structurally related to agouti protein. Overexpression of either of these proteins results in obesity. However the effect of exogenous Agrp and its in vivo interaction with alpha-melanocyte stimulating hormone (alphaMSH), the likely endogenous melanocortin 3 and 4 receptor (MC3-R and MC4-R) agonist, have not been demonstrated. We report that 1 nmol of Agrp(83-132), a C-terminal fragment of Agrp, when administered intracerebroventricularly (ICV) into rats, increased food intake over a 24-h period (23.0+/-1.4 g saline vs 32.9+/-2.3 g Agrp, pinhibition of cAMP activation to that previously reported for the full length peptide. In conclusion, Agrp(83-132) administered i.c.v. increases feeding with long lasting effects and is able to inhibit the action of alphaMSH. This interaction may be mediated by the MC3-R and/or MC4-R.

  12. Alpha-adrenergic receptors in rat skeletal muscle

    DEFF Research Database (Denmark)

    Rattigan, S; Appleby, G J; Edwards, S J

    1986-01-01

    Sarcolemma-enriched preparations from muscles rich in slow oxidative red fibres contained specific binding sites for the alpha 1 antagonist, prazosin (e.g. soleus Kd 0.13 nM, Bmax 29 fmol/mg protein). Binding sites for prazosin were almost absent from white muscle. Displacement of prazosin bindin...

  13. Global analysis of estrogen receptor beta binding to breast cancer cell genome reveals an extensive interplay with estrogen receptor alpha for target gene regulation.

    Science.gov (United States)

    Grober, Oli M V; Mutarelli, Margherita; Giurato, Giorgio; Ravo, Maria; Cicatiello, Luigi; De Filippo, Maria Rosaria; Ferraro, Lorenzo; Nassa, Giovanni; Papa, Maria Francesca; Paris, Ornella; Tarallo, Roberta; Luo, Shujun; Schroth, Gary P; Benes, Vladimir; Weisz, Alessandro

    2011-01-14

    Estrogen receptors alpha (ERα) and beta (ERβ) are transcription factors (TFs) that mediate estrogen signaling and define the hormone-responsive phenotype of breast cancer (BC). The two receptors can be found co-expressed and play specific, often opposite, roles, with ERβ being able to modulate the effects of ERα on gene transcription and cell proliferation. ERβ is frequently lost in BC, where its presence generally correlates with a better prognosis of the disease. The identification of the genomic targets of ERβ in hormone-responsive BC cells is thus a critical step to elucidate the roles of this receptor in estrogen signaling and tumor cell biology. Expression of full-length ERβ in hormone-responsive, ERα-positive MCF-7 cells resulted in a marked reduction in cell proliferation in response to estrogen and marked effects on the cell transcriptome. By ChIP-Seq we identified 9702 ERβ and 6024 ERα binding sites in estrogen-stimulated cells, comprising sites occupied by either ERβ, ERα or both ER subtypes. A search for TF binding matrices revealed that the majority of the binding sites identified comprise one or more Estrogen Response Element and the remaining show binding matrixes for other TFs known to mediate ER interaction with chromatin by tethering, including AP2, E2F and SP1. Of 921 genes differentially regulated by estrogen in ERβ+ vs ERβ- cells, 424 showed one or more ERβ site within 10 kb. These putative primary ERβ target genes control cell proliferation, death, differentiation, motility and adhesion, signal transduction and transcription, key cellular processes that might explain the biological and clinical phenotype of tumors expressing this ER subtype. ERβ binding in close proximity of several miRNA genes and in the mitochondrial genome, suggests the possible involvement of this receptor in small non-coding RNA biogenesis and mitochondrial genome functions. Results indicate that the vast majority of the genomic targets of ERβ can bind

  14. Global analysis of estrogen receptor beta binding to breast cancer cell genome reveals an extensive interplay with estrogen receptor alpha for target gene regulation

    Directory of Open Access Journals (Sweden)

    Papa Maria

    2011-01-01

    Full Text Available Abstract Background Estrogen receptors alpha (ERα and beta (ERβ are transcription factors (TFs that mediate estrogen signaling and define the hormone-responsive phenotype of breast cancer (BC. The two receptors can be found co-expressed and play specific, often opposite, roles, with ERβ being able to modulate the effects of ERα on gene transcription and cell proliferation. ERβ is frequently lost in BC, where its presence generally correlates with a better prognosis of the disease. The identification of the genomic targets of ERβ in hormone-responsive BC cells is thus a critical step to elucidate the roles of this receptor in estrogen signaling and tumor cell biology. Results Expression of full-length ERβ in hormone-responsive, ERα-positive MCF-7 cells resulted in a marked reduction in cell proliferation in response to estrogen and marked effects on the cell transcriptome. By ChIP-Seq we identified 9702 ERβ and 6024 ERα binding sites in estrogen-stimulated cells, comprising sites occupied by either ERβ, ERα or both ER subtypes. A search for TF binding matrices revealed that the majority of the binding sites identified comprise one or more Estrogen Response Element and the remaining show binding matrixes for other TFs known to mediate ER interaction with chromatin by tethering, including AP2, E2F and SP1. Of 921 genes differentially regulated by estrogen in ERβ+ vs ERβ- cells, 424 showed one or more ERβ site within 10 kb. These putative primary ERβ target genes control cell proliferation, death, differentiation, motility and adhesion, signal transduction and transcription, key cellular processes that might explain the biological and clinical phenotype of tumors expressing this ER subtype. ERβ binding in close proximity of several miRNA genes and in the mitochondrial genome, suggests the possible involvement of this receptor in small non-coding RNA biogenesis and mitochondrial genome functions. Conclusions Results indicate that the

  15. Pristanic acid and phytanic acid: naturally occurring ligands for the nuclear receptor peroxisome proliferator-activated receptor alpha

    NARCIS (Netherlands)

    Zomer, A. W.; van der Burg, B.; Jansen, G. A.; Wanders, R. J.; Poll-The, B. T.; van der Saag, P. T.

    2000-01-01

    Phytanic acid and pristanic acid are branched-chain fatty acids, present at micromolar concentrations in the plasma of healthy individuals. Here we show that both phytanic acid and pristanic acid activate the peroxisome proliferator-activated receptor alpha (PPARalpha) in a concentration-dependent

  16. Analysis of Paired Primary-Metastatic Hormone-Receptor Positive Breast Tumors (HRPBC Uncovers Potential Novel Drivers of Hormonal Resistance.

    Directory of Open Access Journals (Sweden)

    Luis Manso

    Full Text Available We sought to identify genetic variants associated with disease relapse and failure to hormonal treatment in hormone-receptor positive breast cancer (HRPBC. We analyzed a series of HRPBC with distant relapse, by sequencing pairs (n = 11 of tumors (primary and metastases at >800X. Comparative genomic hybridization was performed as well. Top hits, based on the frequency of alteration and severity of the changes, were tested in the TCGA series. Genes determining the most parsimonious prognostic signature were studied for their functional role in vitro, by performing cell growth assays in hormonal-deprivation conditions, a setting that mimics treatment with aromatase inhibitors. Severe alterations were recurrently found in 18 genes in the pairs. However, only MYC, DNAH5, CSFR1, EPHA7, ARID1B, and KMT2C preserved an independent prognosis impact and/or showed a significantly different incidence of alterations between relapsed and non-relapsed cases in the TCGA series. The signature composed of MYC, KMT2C, and EPHA7 best discriminated the clinical course, (overall survival 90,7 vs. 144,5 months; p = 0.0001. Having an alteration in any of the genes of the signature implied a hazard ratio of death of 3.25 (p<0.0001, and early relapse during the adjuvant hormonal treatment. The presence of the D348N mutation in KMT2C and/or the T666I mutation in the kinase domain of EPHA7 conferred hormonal resistance in vitro. Novel inactivating mutations in KMT2C and EPHA7, which confer hormonal resistance, are linked to adverse clinical course in HRPBC.

  17. Progesterone withdrawal reduces paired-pulse inhibition in rat hippocampus: dependence on GABA(A) receptor alpha4 subunit upregulation.

    Science.gov (United States)

    Hsu, Fu-Chun; Smith, Sheryl S

    2003-01-01

    Withdrawal from the endogenous steroid progesterone (P) after chronic administration increases anxiety and seizure susceptibility via declining levels of its potent GABA-modulatory metabolite 3alpha-OH-5alpha-pregnan-20-one (3alpha,5alphaTHP). This 3alpha,5alpha-THP withdrawal also results in a decreased decay time constant for GABA-gated current assessed using whole cell patch-clamp techniques on pyramidal cells acutely dissociated from CA1 hippocampus. The purpose of this study was to test the hypothesis that the decreases in total integrated GABA-gated current observed at the level of the isolated pyramidal cell would be manifested as a reduced GABA inhibition at the circuit level following hormone withdrawal. Toward this end, adult, female rats were administered P via subcutaneous capsule for 3 wk using a multiple withdrawal paradigm. We then evaluated paired-pulse inhibition (PPI) of pyramidal neurons in CA1 hippocampus using extracellular recording techniques in hippocampal slices from rats 24 h after removal of the capsule (P withdrawal, P Wd). The population spike (PS) was recorded at the stratum pyramidale following homosynaptic orthodromic stimulation in the nearby stratum radiatum. The threshold for eliciting a response was decreased after P Wd, and the mean PS amplitude was significantly increased compared with control values at this time. Paired pulses with 10-ms inter-pulse intervals were then applied across an intensity range from 2 to 20 times threshold. Evaluation of paired-pulse responses showed a significant 40-50% reduction in PPI for PS recorded in the hippocampal CA1 region after P Wd, suggesting an increase in circuit excitability. At this time, enhancement of PPI by the benzodiazepine lorazepam (LZM; 10 microM) was prevented, while pentobarbital (10 microM) potentiation of PPI was comparable to control levels of response. These data are consistent with upregulation of the alpha4 subunit of the GABA(A) receptor (GABAR) as we have previously

  18. Prostaglandin F2-alpha receptor (FPr expression on porcine corpus luteum microvascular endothelial cells (pCL-MVECs

    Directory of Open Access Journals (Sweden)

    Forni Monica

    2007-07-01

    Full Text Available Abstract Background The corpus luteum (CL is a transient endocrine gland and prostaglandin F2-alpha is considered to be the principal luteolysin in pigs. In this species, the in vivo administration of prostaglandin F2-alpha induces apoptosis in large vessels as early as 6 hours after administration. The presence of the prostaglandin F2-alpha receptor (FPr on the microvascular endothelial cells (pCL-MVECs of the porcine corpus luteum has not yet been defined. The aim of the study was to assess FPr expression in pCL-MVECs in the early and mid-luteal phases (EL-p, ML-p, and during pregnancy (P-p. Moreover, the effectiveness of prostaglandin F2-alpha treatment in inducing pCL-MVEC apoptosis was tested. Methods Porcine CLs were collected in the EL and ML phases and during P-p. All CLs from each animal were minced together and the homogenates underwent enzymatic digestion. The pCL-MVECs were then positively selected by an immunomagnetic separation protocol using Dynabeads coated with anti-CD31 monoclonal antibody and seeded in flasks in the presence of EGM 2-MV (Microvascular Endothelial Cell Medium-2. After 4 days of culture, the cells underwent additional immunomagnetic selection and were seeded in flasks until the confluent stage. PCR Real time, western blot and immunodetection assays were utilized to assess the presence of FPr on pCL-MVEC primary cultures. Furthermore, the influence of culture time (freshly isolated, cultured overnight and at confluence and hormonal treatment (P4 and E2 on FPr expression in pCL-MVECs was also investigated. Apoptosis was detected by TUNEL assay of pCL-MVECs exposed to prostaglandin F2-alpha. Results We obtained primary cultures of pCL-MVECs from all animals. FPr mRNA and protein levels showed the highest value (ANOVA in CL-MVECs derived from the early-luteal phase. Moreover, freshly isolated MVECs showed a higher FPr mRNA value than those cultured overnight and confluent cells (ANOVA. prostaglandin F2-alpha

  19. Pituitary gonadotrophic hormone synthesis, secretion, subunit gene expression and cell structure in normal and follicle-stimulating hormone β knockout, follicle-stimulating hormone receptor knockout, luteinising hormone receptor knockout, hypogonadal and ovariectomised female mice.

    Science.gov (United States)

    Abel, M H; Widen, A; Wang, X; Huhtaniemi, I; Pakarinen, P; Kumar, T R; Christian, H C

    2014-11-01

    To investigate the relationship between gonadotroph function and ultrastructure, we have compared, in parallel in female mice, the effects of several different mutations that perturb the hypothalamic-pituitary-gonadal axis. Specifically, serum and pituitary gonadotrophin concentrations, gonadotrophin gene expression, gonadotroph structure and number were measured. Follicle-stimulating hormone β knockout (FSHβKO), follicle-stimulating hormone receptor knockout (FSHRKO), luteinising hormone receptor knockout (LuRKO), hypogonadal (hpg) and ovariectomised mice were compared with control wild-type or heterozygote female mice. Serum levels of LH were elevated in FSHβKO and FSHRKO compared to heterozygote females, reflecting the likely decreased oestrogen production in KO females, as demonstrated by the threadlike uteri and acyclicity. As expected, there was no detectable FSH in the serum or pituitary and an absence of expression of the FSHβ subunit gene in FSHβKO mice. However, there was a significant increase in expression of the FSHβ and LHβ subunit genes in FSHRKO female mice. The morphology of FSHβKO and FSHRKO gonadotrophs was not significantly different from the control, except that secretory granules in FSHRKO gonadotrophs were larger in diameter. In LuRKO and ovariectomised mice, stimulation of LHβ and FSHβ mRNA, as well as serum protein concentrations, were reflected in subcellular changes in gonadotroph morphology, including more dilated rough endoplasmic reticula and fewer, larger secretory granules. In the gonadotophin-releasing hormone deficient hpg mouse, gonadotrophin mRNA and protein levels were significantly lower than in control mice and gonadotrophs were correspondingly smaller with less abundant endoplasmic reticula and reduced numbers of secretory granules. In summary, major differences in pituitary content and serum concentrations of the gonadotrophins LH and FSH were found between control and mutant female mice. These changes were

  20. Sex hormone receptors are present in the human suprachiasmatic nucleus

    NARCIS (Netherlands)

    Kruijver, Frank P. M.; Swaab, Dick F.

    2002-01-01

    The suprachiasmatic nucleus (SCN) is the clock of the brain that orchestrates circadian and circannual biological rhythms, such as the rhythms of hormones, body temperature, sleep and mood. These rhythms are frequently disturbed in menopause and even more so in dementia and can be restored in

  1. Differential expression of estrogen receptors alpha and beta mRNA during differentiation of human osteoblast SV-HFO cells

    NARCIS (Netherlands)

    J. Arts (Janine); J.M.M.F. Janssen (Josine); J.A. Gustafsson (Jan-Ake); C.W.G.M. Löwik (Clemens); H.A.P. Pols (Huib); J.P.T.M. van Leeuwen (Hans); G.G.J.M. Kuiper (George)

    1997-01-01

    textabstractEstrogens have been shown to be essential for maintaining a sufficiently high bone mineral density and ER alpha expression has been demonstrated in bone cells. Recently, a novel estrogen receptor, estrogen receptor beta (ERbeta) has been identified. Here

  2. Withdrawal reactions following cessation of central alpha-adrenergic receptor agonists.

    Science.gov (United States)

    Reid, J L; Campbell, B C; Hamilton, C A

    1984-01-01

    Interruption of long-term treatment with alpha 2-adrenergic receptor agonists may be associated with reversal of their hemodynamic effects, clinical and biochemical evidence of increased peripheral sympathetic activity, and behavioral responses similar to those seen after narcotic or alcohol withdrawal. Reactions are most commonly observed after short-acting imidazoline drugs such as clonidine and tiamenidine. Reactions are less common after longer acting agents such as guanfacine. A new management approach to withdrawal has been evaluated, which uses a combination of alpha 1-blockade (prazosin) and cardioselective beta-blockade (atenolol) together with a benzodiazepine (chlordiazepoxide). Withdrawal reactions were not observed in eight patients in whom clonidine was withdrawn under cover of these agents. The mechanism of the withdrawal reaction may involve agonist-induced down regulation of alpha 2-adrenergic receptor affinity, number, or both. Experimental studies with the irreversible alpha-antagonist phenoxybenzamine on the turnover of alpha 2-receptors suggest that recovery of receptor number may be much slower in the brain than in the periphery.

  3. Internalization and recycling of receptor-bound gonadotropin-releasing hormone agonist in pituitary gonadotropes

    Energy Technology Data Exchange (ETDEWEB)

    Schvartz, I.; Hazum, E.

    1987-12-15

    The fate of cell surface gonadotropin-releasing hormone (GnRH) receptors on pituitary cells was studied utilizing lysosomotropic agents and monensin. Labeling of pituitary cells with a photoreactive GnRH derivative, (azidobenzoyl-D-Lys6)GnRH, revealed a specific band of Mr = 60,000. When photoaffinity-labeled cells were exposed to trypsin immediately after completion of the binding, the radioactivity incorporated into the Mr = 60,000 band decreased, with a concomitant appearance of a proteolytic fragment (Mr = 45,000). This fragment reflects cell surface receptors. Following GnRH binding, the hormone-receptor complexes underwent internalization, partial degradation, and recycling. The process of hormone-receptor complex degradation was substantially prevented by lysosomotropic agents, such as chloroquine and methylamine, or the proton ionophore, monensin. Chloroquine and monensin, however, did not affect receptor recycling, since the tryptic fragment of Mr = 45,000 was evident after treatment with these agents. This suggests that recycling of GnRH receptors in gonadotropes occurs whether or not the internal environment is acidic. Based on these findings, we propose a model describing the intracellular pathway of GnRH receptors.

  4. EVALUATION OF STEROID HORMONES AND THEIR RECEPTORS IN DEVELOPMENT AND PROGRESSION OF RENAL CELL CARCINOMA

    Directory of Open Access Journals (Sweden)

    Nigel Bennett

    2014-06-01

    Full Text Available Steroid hormones and their receptors have important roles in normal kidney biology, and alterations in their expression and function help explain the differences in development of kidney diseases, such as nephrotic syndrome and chronic kidney disease. The distinct gender difference in incidence of renal cell carcinoma (RCC, with males having almost twice the incidence as females globally, also suggests a role for sex hormones or their receptors in RCC development and progression. There was a peak in interest in evaluating the roles of androgen and estrogen receptors in RCC pathogenesis in the late 20th century, with some positive outcomes for RCC therapy that targeted estrogen receptors, especially for metastatic disease. Since that time, however, there have been few studies that look at use of steroid hormone modulators for RCC, especially in the light of new therapies such as the tyrosine kinase inhibitors and new immune therapies, which are having some success for treatment of metastatic RCC. This review summarises past and current literature and attempts to stimulate renewed interest in research into the steroid hormones and their receptors, which might be used to effect, for example, in combination with the other newer targeted therapies for RCC.

  5. Purification and characterization of the human platelet. cap alpha. /sub 2/-adrenergic receptor

    Energy Technology Data Exchange (ETDEWEB)

    Shreeve, S.M.; Kerlavage, A.R.; Fraser, C.M.; Mariani, A.P.; Venter, J.C.

    1986-05-01

    The ..cap alpha../sub 2/-receptor (..cap alpha../sub 2/-R) from human platelets has been purified to homogeneity using a four step process. An affinity column was prepared by coupling p-aminoclonidine to CH-Sepharose 4B via the p-NH/sub 2/ group. Digitonin solubilized ..cap alpha../sub 2/-R bound to the affinity matrix were eluted with 100 ..mu..M phentolamine and directly applied to a DEAE-Sepharose column. Bound receptors were eluted with a linear gradient of 0-500 mM NaCl, pooled and chromatographed on HPLC size exclusion columns. Three peaks of ..cap alpha../sub 2/-R binding were eluted from HPLC columns (t = 33, 42, 47 min). Radioiodination of HPLC eluates and analysis by SDS-PAGE indicated that ..cap alpha../sub 2/-R binding was associated with a 75-85 kDa protein. These data suggest that the ..cap alpha../sub 2/-R may exist in monomeric and oligomeric forms in the purified state and support previous target size data which indicate that the ..cap alpha../sub 2/-R exists as a dimer in the native membrane. The pure radioiodinated ..cap alpha../sub 2/-R (77-85 kDa) is a glycoprotein with terminal sialic acid or N-acetylglucosamine residues and has a pI of 4.1 on column isoelectric focusing. These data are consistent with those previously reported on the partially purified ..cap alpha../sub 2/-R. Electron micrographs confirm the oligomeric nature and size of the pure ..cap alpha../sub 2/-R.

  6. The increase of alpha-melanocyte-stimulating hormone in the plasma of chronic fatigue syndrome patients

    Directory of Open Access Journals (Sweden)

    Shishioh-Ikejima Nobue

    2010-08-01

    Full Text Available Abstract Background Despite extensive research, no reliable biological marker for chronic fatigue syndrome (CFS has yet been identified. However, hyperactivation of melanotrophs in the pituitary gland and increased levels of plasma alpha-melanocyte-stimulating hormone (α-MSH have recently been detected in an animal model of chronic stress. Because CFS is considered to be caused partly by chronic stress events, increased α-MSH plasma levels may also occur in CFS patients. We therefore examined α-MSH levels in CFS patients. Methods Fifty-five CFS patients, who were previously diagnosed within 10 years of with the disease, were enrolled in this study. Thirty healthy volunteers were studied as controls. Fasting bloods samples were collected in the morning and evaluated for their plasma levels of α-MSH, adrenocorticotropic hormone (ACTH, serum cortisol and dehydroepiandrosterone sulfate (DHEA-S. Mean levels of α-MSH were compared between the CFS and control groups using Welch's t test. Results The mean plasma α-MSH concentration in the CFS group (17.9 ± 1.0 pg/mL was significantly higher than that in healthy controls (14.5 ± 1.0 pg/mL, p = 0.02. However, there was a wide range of values in the CFS group. The factors correlated with the plasma α-MSH values were analyzed using Spearman's rank correlation. A negative correlation was found between the duration of the CFS and the plasma α-MSH values (p = 0.04, rs = -0.28, but no correlations with ACTH, cortisol or DHEA-S levels were identified (p = 0.55, 0.26, 0.33, respectively. The CFS patients were divided into two groups: patients diagnosed for ≤ 5 years' duration, and those diagnosed for 5-10 years' duration. They were compared with the healthy controls using one-way ANOVA and Tukey-Kramer multiple comparison tests. The mean α-MSH concentration in the ≤ 5 years group was 20.8 ± 1.2 pg/mL, which was significantly higher than that in the healthy controls (p Conclusions CFS patients with

  7. Estradiol upregulates calcineurin expression via overexpression of estrogen receptor alpha gene in systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    Hui-Li Lin

    2011-04-01

    Full Text Available Systemic lupus erythematosus (SLE is an autoimmune disease primarily affecting women (9:1 compared with men. To investigate the influence of female sex hormone estrogen on the development of female-biased lupus, we compared the expression of estrogen receptor alpha (ERα gene and protein levels as well as expression of T-cell activation gene calcineurin in response to estrogen in peripheral blood lymphocytes (PBLs from SLE patients and normal controls. PBLs were isolated from 20 female SLE patients and 6 normal female controls. The amount of ERα protein in PBL was measured by flow cytometry. The expression of ERα and calcineurin messenger RNA was measured by semi-quantitative reverse transcription-polymerase chain reaction. Calcineurin phosphatase activity was measured by calcineurin assay kit. The expression of ERα messenger RNA and ERα protein was significantly increased (p=0.001 and p=0.023, respectively in PBL from SLE patients compared with that from normal controls. In addition, the basal calcineurin in PBL from SLE patients was significantly higher (p=0.000 than that from normal controls, and estrogen-induced expression of calcineurin was increased (p=0.007 in PBL from SLE patients compared with that from normal controls, a 3.15-fold increase. This increase was inhibited by the ERα antagonism ICI 182,780. The effects of ER antagonism were also found in calcineurin activity. These data suggest that overexpression of ERα gene and enhanced activation of calcineurin in response to estrogen in PBL may contribute to the pathogenesis of female dominant in SLE.

  8. Preliminary Molecular Dynamic Simulations of the Estrogen Receptor Alpha Ligand Binding Domain from Antagonist to Apo

    Directory of Open Access Journals (Sweden)

    Adrian E. Roitberg

    2008-06-01

    Full Text Available Estrogen receptors (ER are known as nuclear receptors. They exist in the cytoplasm of human cells and serves as a DNA binding transcription factor that regulates gene expression. However the estrogen receptor also has additional functions independent of DNA binding. The human estrogen receptor comes in two forms, alpha and beta. This work focuses on the alpha form of the estrogen receptor. The ERα is found in breast cancer cells, ovarian stroma cells, endometrium, and the hypothalamus. It has been suggested that exposure to DDE, a metabolite of DDT, and other pesticides causes conformational changes in the estrogen receptor. Before examining these factors, this work examines the protein unfolding from the antagonist form found in the 3ERT PDB crystal structure. The 3ERT PDB crystal structure has the estrogen receptor bound to the cancer drug 4-hydroxytamoxifen. The 4-hydroxytamoxifen ligand was extracted before the simulation, resulting in new conformational freedom due to absence of van der Waals contacts between the ligand and the receptor. The conformational changes that result expose the binding clef of the co peptide beside Helix 12 of the receptor forming an apo conformation. Two key conformations in the loops at either end of the H12 are produced resulting in the antagonist to apo conformation transformation. The results were produced over a 42ns Molecular Dynamics simulation using the AMBER FF99SB force field.

  9. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor suppressor in hepatocellular carcinoma.

    Science.gov (United States)

    Liu, Rui; Zhang, Haiyang; Zhang, Yan; Li, Shuang; Wang, Xinyi; Wang, Xia; Wang, Cheng; Liu, Bin; Zen, Ke; Zhang, Chen-Yu; Zhang, Chunni; Ba, Yi

    2017-04-01

    Peroxisome proliferator-activated receptor gamma coactivator-1 alpha plays a crucial role in regulating the biosynthesis of mitochondria, which is closely linked to the energy metabolism in various tumors. This study investigated the regulatory role of peroxisome proliferator-activated receptor gamma coactivator-1 alpha in the pathogenesis of hepatocellular carcinoma. In this study, the changes of peroxisome proliferator-activated receptor gamma coactivator-1 alpha messenger RNA levels between normal human liver and hepatocellular carcinoma tissue were examined by quantitative reverse transcription polymerase chain reaction. Knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by RNA interference in the human liver cell line L02, while overexpression of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha complementary DNA in the human hepatocarcinoma cell line HepG2. Cellular morphological changes were observed via optical and electron microscopy. Cellular apoptosis was determined by Hoechst 33258 staining. In addition, the expression levels of 21,400 genes in tissues and cells were detected by microarray. It was shown that peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression was significantly downregulated in hepatocellular carcinoma compared with normal liver tissues. After knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression in L02 cells, cells reverted to immature and dedifferentiated morphology exhibiting cancerous tendency. Apoptosis occurred in the HepG2 cells after transfection by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha. Microarray analysis showed consistent results. The results suggest that peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor

  10. Novel Hormone Receptors Present in Apocrine Cystadenoma of the Eyelid.

    Science.gov (United States)

    Brown, Sarah E; Friedman, Alan H; Phelps, Robert G; Bleiweiss, Ira J; Wu, Albert Y

    A 53-year-old woman presented with an apocrine cystadenoma of the right upper eyelid. Histologic examination revealed proliferating epithelial cells with apocrine snouts and occasional mitotic figures. Immunohistochemical analysis revealed a Ki-67 index of 15% and positive staining for synaptophysin, chromogranin, estrogen receptor, progesterone receptor, gross cystic disease fluid protein (GCDFP)-15, and mammoglobin. The complement of positive immunomarkers in this case reinforces the importance of total excision and careful histologic assessment.

  11. Genome inventory and analysis of nuclear hormone receptors in ...

    Indian Academy of Sciences (India)

    Prakash

    Genome analysis of nuclear receptors in Tetraodon. 1. J. Biosci. 32(1), January 2007. Tetraodon nigroviridis nuclear receptors. NR. Accession No. No. Gene. DBD. LBD. Invariable Splice junction (D). Chromosome. Subfamily 1: NR1A1. CAF90676.1. 2. TRA f f no. 2. NR1A1. CAG02086.1*. 16. TRA f f yes. UD. NR1A2.

  12. Influence of ascorbic acid on in vivo amidation of alpha-melanocyte stimulating hormone in guinea pig pituitary

    DEFF Research Database (Denmark)

    Fenger, M; Hilsted, L

    1988-01-01

    The effect of ascorbic acid depletion on the amidation of alphamelanocyte stimulating hormone (alpha MSH) was studied in vivo in guinea pig pituitary. After four weeks, the concentration of ascorbic acid was 1.20 +/- 0.11 mumol/g tissue (mean +/- SD) in the pituitary and 0.34 +/- 0.07 mumol......-39) immunoreactivity was observed in the depleted guinea pigs. Gel chromatography and reversed-phase high-performance luquid chromatography showed that the alpha MSH and ACTH (1-14) immunoreactivity was of low molecular weight and partly mono- or diacetylated. Depletion of ascorbic acid had no influence on the degree...... of acetylation of alpha MSH and ACTH (1-14). It is concluded that depletion of ascorbic acid reduces the in vivo amidation of ACTH (1-14) in the guinea pig pituitary....

  13. The localization of estrogen receptor alpha and its function in the ovaries of postmenopausal women.

    Directory of Open Access Journals (Sweden)

    Jacek Brodowski

    2008-01-01

    Full Text Available The localization of estrogen receptor alpha (ERalpha in the ovaries of postmenopausal women is a very up-to-date topic in the aspect of using estrogens therapy in the clinical situations of different type. In ovaries of reproductive age women ERalpha is present in ovary stroma, theca and granulosa cells, ovary surface epithelium (OSE and in corpus luteum. The ovaries of postmenopausal women are smaller than those of women at the reproductive age, the division into cortex and medulla gets blurred, the ovaries have no follicles any longer, and the stroma is mainly composed of fibrous connective tissue, corpora albicantia, nerves, and blood and lymphatic vessels. The aim of our study was to investigate the immunolocalization and immunoexpression of ERalpha in the ovaries of postmenopausal women. The study involved 50 postmenopausal women who had their ovaries removed by laparotomy due to non-neoplastic diseases of the uterus. The women were divided into 3 groups (A, B, and C depending on the time that had passed since the last menstruation. Group A consisted of women who had their last menstruation no more than 5 years earlier, in group B menopause occurred 5 to 10 years earlier, group C was composed of patients who had the last menstruation over 10 years earlier. In all the patients concentrations of follicle stimulating hormone (FSH, luteinizing stimulating hormone (LH, estradiol (E2, testosterone (T, androstendione (A and dehydroepiandrosterone sulphate (DHEAS in blood plasma were measured. Ovarian tissue was obtained during surgery. For morphological studies, ovaries were fixed in Bouin;s solution and 4% formalin and embedded in paraffin. Morphological analysis was carried out after hematoxylin-eosin (HE staining. Comparing to groups A and B, the ovaries in group C contained a small number of corpora albicantia located in the medullary part as well as thinned blood vessels and few lymphatic vessels and nerves. For immunoohistochemical

  14. Activation of peroxisome proliferator-activated receptor-{alpha} enhances fatty acid oxidation in human adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joo-Young; Hashizaki, Hikari; Goto, Tsuyoshi; Sakamoto, Tomoya; Takahashi, Nobuyuki [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan); Kawada, Teruo, E-mail: fat@kais.kyoto-u.ac.jp [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2011-04-22

    Highlights: {yields} PPAR{alpha} activation increased mRNA expression levels of adipocyte differentiation marker genes and GPDH activity in human adipocytes. {yields} PPAR{alpha} activation also increased insulin-dependent glucose uptake in human adipocytes. {yields} PPAR{alpha} activation did not affect lipid accumulation in human adipocytes. {yields} PPAR{alpha} activation increased fatty acid oxidation through induction of fatty acid oxidation-related genes in human adipocytes. -- Abstract: Peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}) is a key regulator for maintaining whole-body energy balance. However, the physiological functions of PPAR{alpha} in adipocytes have been unclarified. We examined the functions of PPAR{alpha} using human multipotent adipose tissue-derived stem cells as a human adipocyte model. Activation of PPAR{alpha} by GW7647, a potent PPAR{alpha} agonist, increased the mRNA expression levels of adipocyte differentiation marker genes such as PPAR{gamma}, adipocyte-specific fatty acid-binding protein, and lipoprotein lipase and increased both GPDH activity and insulin-dependent glucose uptake level. The findings indicate that PPAR{alpha} activation stimulates adipocyte differentiation. However, lipid accumulation was not changed, which is usually observed when PPAR{gamma} is activated. On the other hand, PPAR{alpha} activation by GW7647 treatment induced the mRNA expression of fatty acid oxidation-related genes such as CPT-1B and AOX in a PPAR{alpha}-dependent manner. Moreover, PPAR{alpha} activation increased the production of CO{sub 2} and acid soluble metabolites, which are products of fatty acid oxidation, and increased oxygen consumption rate in human adipocytes. The data indicate that activation of PPAR{alpha} stimulates both adipocyte differentiation and fatty acid oxidation in human adipocytes, suggesting that PPAR{alpha} agonists could improve insulin resistance without lipid accumulation in adipocytes. The expected

  15. Molecular analysis of the koala reproductive hormones and their receptors: gonadotrophin-releasing hormone (GnRH), follicle-stimulating hormone β and luteinising hormone β with localisation of GnRH.

    Science.gov (United States)

    Busby, E R; Soeta, S; Sherwood, N M; Johnston, S D

    2014-12-01

    During evolution, reproductive hormones and their receptors in the brain-pituitary-gonadal axis have been altered by genetic mechanisms. To understand how the neuroendocrine control of reproduction evolved in mammals, it is important to examine marsupials, the closest group to placental mammals. We hypothesised that at least some of the hormones and receptors found in placental mammals would be present in koala, a marsupial. We examined the expression of koala mRNA for the reproductive molecules. Koala cDNAs were cloned from brain for gonadotrophin-releasing hormones (GnRH1 and GnRH2) or from pituitary for GnRH receptors, types I and II, follicle-stimulating hormone (FSH)β and luteinising hormone (LH)β, and from gonads for FSH and LH receptors. Deduced proteins were compared by sequence alignment and phylogenetic analysis with those of other vertebrates. In conclusion, the koala expressed mRNA for these eight putative reproductive molecules, whereas at least one of these molecules is missing in some species in the amniote lineage, including humans. In addition, GnRH1 and 2 are shown by immunohistochemistry to be expressed as proteins in the brain. © 2014 British Society for Neuroendocrinology.

  16. The role of tumour necrosis factor alpha and soluble tumour necrosis factor alpha receptors in the symptomatology of schizophrenia.

    Science.gov (United States)

    Turhan, Levent; Batmaz, Sedat; Kocbiyik, Sibel; Soygur, Arif Haldun

    2016-07-01

    Background Immunological mechanisms may be responsible for the development and maintenance of schizophrenia symptoms. Aim The aim of this study is to measure tumour necrosis factor-alpha (TNF-α), soluble tumour necrosis factor-alpha receptor I (sTNF-αRI), and soluble tumour necrosis factor-alpha receptor II (sTNF-αRII) levels in patients with schizophrenia and healthy individuals, and to determine their relationship with the symptoms of schizophrenia. Methods Serum TNF-α, sTNF-αRI and sTNF-αRII levels were measured. The Positive and Negative Syndrome Scale (PANSS) was administered for patients with schizophrenia (n = 35), and the results were compared with healthy controls (n = 30). Hierarchical regression analyses were undertaken to predict the levels of TNF-α, sTNF-αRI and sTNF-αRII. Results No significant difference was observed in TNF-α levels, but sTNF-αRI and sTNF-αRII levels were lower in patients with schizophrenia. Serum sTNF-αRI and sTNF-αRII levels were found to be negatively correlated with the negative subscale score of the PANSS, and sTNF-αRI levels were also negatively correlated with the total score of the PANSS. Smoking, gender, body mass index were not correlated with TNF-α and sTNF-α receptor levels. Conclusions These results suggest that there may be a change in anti-inflammatory response in patients with schizophrenia due to sTNF-αRI and sTNF-αRII levels. The study also supports low levels of TNF activity in schizophrenia patients with negative symptoms.

  17. The effects of the alpha2-adrenergic receptor agonists clonidine and rilmenidine, and antagonists yohimbine and efaroxan, on the spinal cholinergic receptor system in the rat

    DEFF Research Database (Denmark)

    Abelson, Klas S P; Höglund, A Urban

    2004-01-01

    and rilmenidine increased, while yohimbine decreased spinal acetylcholine release. Efaroxan affected acetylcholine release differently depending on concentration. Nicotinic receptor blockade attenuated the effect of all ligands. All ligands showed poor binding affinity for muscarinic receptors. On the other hand......Cholinergic agonists produce spinal antinociception via mechanisms involving an increased release of intraspinal acetylcholine. The cholinergic receptor system interacts with several other receptor types, such as alpha2-adrenergic receptors. To fully understand these interactions, the effects...... of various receptor ligands on the cholinergic system must be investigated in detail. This study was initiated to investigate the effects of the alpha2-adrenergic receptor agonists clonidine and rilmenidine and the alpha2-adrenergic receptor antagonists yohimbine and efaroxan on spinal cholinergic receptors...

  18. ERR Gamma: Does an Orphan Nuclear Receptor Link Steroid Hormone Biogenesis to Endocrine Resistance?

    Science.gov (United States)

    2007-09-01

    tandem copies of the consensus sequence for SF-1RE (TCAAGGTCA; generously provided by Dr. Jean-Marc Vanacker, INSERM, Montpellier , France) (6) and...activity, Mol. Endocrinol. 20 (2006) 3120–3132. [147] D. Chen, P.E. Pace , R.C. Coombes, S. Ali, Phosphoryla- tion of human estrogen receptor alpha by protein...1998) 13317–13323. [154] D. Chen, T. Riedl, E. Washbrook, P.E. Pace , R.C. Coombes, J.M. Egly, et al., Activation of estrogen receptor alpha by S118

  19. Follicle stimulating hormone modulates ovarian stem cells through alternately spliced receptor variant FSH-R3

    OpenAIRE

    Patel, Hiren; Bhartiya, Deepa; Parte, Seema; Gunjal, Pranesh; Yedurkar, Snehal; Bhatt, Mithun

    2013-01-01

    Background We have earlier reported that follicle stimulating hormone (FSH) modulates ovarian stem cells which include pluripotent, very small embryonic-like stem cells (VSELs) and their immediate descendants ?progenitors? termed ovarian germ stem cells (OGSCs), lodged in adult mammalian ovarian surface epithelium (OSE). FSH may exert pleiotropic actions through its alternatively spliced receptor isoforms. Four isoforms of FSH receptors (FSHR) are reported in literature of which FSH-R1 and FS...

  20. Evaluation of 7 {alpha}-O-IADPN as a new potential SPECT opioid receptor imaging agent

    Energy Technology Data Exchange (ETDEWEB)

    Wang, R.F.; Mao, S.Y. [Fujian Medical College, Fuzhou (China). Dept. of Nuclear Medicine; Tafani, J.A.M.; Coulais, Y.; Guiraud, R. [Hospital Purpan, Toulouse (France). Service Central de medicine Nucleaire; Zajac, J.M. [LPTF-CNRS, Toulouse (France)

    1998-03-01

    Full text: A new iodinated diprenorphine antagonist analogue, [{sup 123}I]7 {alpha}.-O-IADPN, [E] - 17-(cyclopropylmethyl) -4,5 (x-epoxy- 18,19-dihydro-3-hydroxy-6-methoxy-7 {alpha}-[1-(3-iodoallyl)oxy-1-methylethyl]-6,14-endo-ethenomorphinan for in vivo and in vitro studies as a potential central nervous system (CNS) opioid receptor imaging agent was developed. In vivo biodistribution and metabolism of 7 {alpha}-O-lADPN in rat demonstrated that 0.16% of the iodinated compound was presented in mouse brain with a degradation-resistant at the first 60 min, and that 36% of the total cerebral radioactivity and 63% of its specific binding to opioid receptors were observed 20 min after i.v. injection. The cerebral radioactivity in mouse brain concentrated in the basal ganglion and cortex, and displayed a remarkably high target-to-non-target ratio (cortex/cerebellum = 60 min post-injection). The in vitro binding studies showed that [{sup 123}I]7 {alpha}-O-IADPN binds non selectively to multiple opioid receptors {mu} = 8 K) with a very high affinity (Ki = 0.4 + 0.2 nM). Ex vivo autoradiography results in mouse further confirmed the high uptake and retention of this agent in basal ganglion region and cortex. The planar imaging of monkey brains after i.v. injection of [{sup 123}I]7 {alpha}-O-IADPN clearly displayed that multiple opioid receptors can be visualized. With the excellent in vitro affinity and in vivo stability to deiodination and high target-to-nontarget ratio, [{sup 123}I]7 {alpha}- O-IADPN appears to be useful as a CNS opioid receptor imaging probe for SPECT in primate and non-primate.

  1. Chronic toxicity of the synthetic hormone 17alpha-ethinylestradiol to Chironomus tentans and Hyalella azteca.

    Science.gov (United States)

    Dussault, Eve B; Balakrishnan, Vimal K; Solomon, Keith R; Sibley, Paul K

    2008-12-01

    The chronic toxicity of the synthetic hormone 17alpha-ethinylestradiol (EE2) was investigated in two benthic invertebrates, the midge Chironomus tentans and the freshwater amphipod Hyalella azteca, in life-cycle water-only assays. In C. tentans, a 50% decrease in emergence was observed at a concentration of 1.5 mg/L; emergence was a more sensitive endpoint than survival, growth, or biomass. Reproduction was not significantly affected by EE2 exposure until a concentration of 3.1 mg/L, where emergence, and therefore reproduction, did not occur. In contrast, reproduction was the most sensitive endpoint in H. azteca (50% decrease in reproduction observed at a concentration of 0.36 mg/L). The sensitivity of the F1 generation to EE2 was also investigated with H. azteca, but was not different from the F0 generation. The data from the present study were combined with those from previous 10-d toxicity assays, to derive acute to chronic toxicity ratios (ACRs) for EE2. The ACRs calculated for EE2 were 13 for C. tentans and 16 for H. azteca, indicating that the application factors currently used in ecological risk assessment for the derivation of chronic toxicity are protective and conservative for these organisms. The results of the present study suggest that chronic toxicity was not mediated by disruption of endocrine pathways. Using a hazard quotient approach, the risk associated with sublethal exposure to EE2 was azteca and C. tentans, indicating that adverse effects are not expected, and that environmental exposure to EE2 likely poses a low risk to benthic invertebrates.

  2. Intracellular processing of growth hormone receptors by adipocytes in primary culture.

    Science.gov (United States)

    Roupas, P; Herington, A C

    1988-05-01

    Rat adipocytes in primary culture have been used to study the intracellular processing of growth hormone (GH) receptors. Pretreatment of adipocytes with 20 micrograms/ml cycloheximide resulted in a rapid decline (t1/2 approximately 45 min) of the 125I-human growth hormone (hGH) binding capacity of the cells. This decline occurred at a faster rate in the presence of extracellular unlabeled hGH (400 ng/ml) and was not due to receptor occupancy. These data suggest that GH receptors turn over rapidly and constitutively on the plasma membrane and in the absence of protein synthesis are not replaced. Dissociation of GH-receptor complexes was shown not to occur at pH 5.5, the pH encountered in the acidic pre-lysosomal compartments (endosomes) where intracellular dissociation of many hormone-receptor complexes takes place. These data, together, suggest that the majority of GH receptors are not recycled but instead suffer the same fate as the majority of GH, i.e. degradation. To determine the rate of appearance of GH receptors at the cell surface, adipocytes were first treated with trypsin and then incubated at 37 degrees C to permit incorporation of any available GH receptors into the plasma membrane. Binding of 125I-hGH recovered to pre-trypsin levels by 2 h. This recovery was completely blocked by concomitant treatment with monensin, cytochalasin B, colchicine and 2,4-dinitrophenol. NH4Cl had no effect on receptor recovery. These data suggest that once GH receptors are synthesized in the rough endoplasmic reticulum, they travel via the Golgi apparatus to the plasma membrane (by processes involving both microfilaments and microtubules) and are then inserted into the plasma membrane in an energy-dependent step.

  3. Original article Expression of Estrogen Alpha and Beta Receptors in ...

    African Journals Online (AJOL)

    mn

    Receptors in Prostate Cancer and Hyperplasia: Immunohistochemical Analysis. J. A. Al-Maghrabi1, T. M. Hassan1, 2, T. A. Abdel-Meguid3, 4, H. A.. Mosli3. 1Departments of Pathology, and 3Urology, King Abdul-Aziz University. Hospital, Jeddah, Saudi Arabia, 2Department of Pathology, Beni-Suef. University, Egypt, and ...

  4. Hormones

    Science.gov (United States)

    Hormones are your body's chemical messengers. They travel in your bloodstream to tissues or organs. They work ... glands, which are special groups of cells, make hormones. The major endocrine glands are the pituitary, pineal, ...

  5. Guanine nucleotide regulation of. cap alpha. /sub 1/-adrenergic receptors of muscle and kidney eptihelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Terman, B.I.; Hughes, R.J.; Slivka, S.R.; Insel, P.A.

    1986-05-01

    The authors have examined the effect of guanine nucleotides on the interaction of adrenergic agents with ..cap alpha../sup 1/-adrenergic receptors of two cell lines, the Madin-Darby Canine Kidney (MDCK) and BC3H-1 muscle cells. While gaunylylimidodiphosphoate (Gpp(NH)p) had no effect on the affinity or the total number of (/sup -3/H)prazosin binding sites in membranes prepared from these cells, the nucleotide decreased the apparent affinity of the agonist epinephrine in competing for (/sup 3/H)prazosin binding sites in both cell types. The EC/sub 50/ of Gpp(NH)p was approx.100 ..mu..M, and a maximal effect was seen at 500 ..mu..M. In contrast, 100 ..mu..M Gpp(NH)p yielding maximal shifts in binding of epinephrine to ..beta..-adrenergic receptors in BC3H-1 cell membranes. Guanine nucleotides were significantly more effective than adenine nucleotides in shifting agonist affinity for the ..cap alpha../sub 1/-receptor and Mg/sup + +/ was required to observe a maximal effect. ..cap alpha../sub 1/-receptor agonists activated phosphatidylinositol (PI) hydrolysis in both cell types, but have no direct effect on membrane adenylate cyclase activity. In intact BC3H-1 cells, ..cap alpha../sub 1/-agonists inhibited ..beta..-adrenergic cAMP production, an effect which appears in preliminary studies not to result from enhanced phosphodieterase activity. These results show that agonist binding to ..cap alpha../sup 1/-adrenergic receptors in mammalian kidney and muscle cells is regulated by guanine nucleotides. This regulation and inturn transmembrane signalling (PI hydrolysis) by these receptors appear to involve a guanine nucleotide binding (G) protein, which may be different than G/sub s/ and G/sub i/.

  6. Peroxisome Proliferator Activated Receptor-Alpha (PPARα) and PPAR Gamma Coactivator-1alpha (PGC-1α) Regulation of Cardiac Metabolism in Diabetes

    OpenAIRE

    Duncan, Jennifer G.

    2011-01-01

    Cardiovascular disease is a leading cause of mortality among patients with diabetes, and heart failure exists even in the absence of coronary disease. Myocardial metabolism is altered in the diabetic heart as a result of changes in substrate availability secondary to insulin resistance. The nuclear receptor peroxisome proliferator activated receptor-alpha (PPARα) and PPAR-gamma coactivator-1alpha (PGC-1α) play important roles in transcriptional regulation of myocardial metabolism and contribu...

  7. Desensitization, Trafficking, and Resensitization of the Pituitary Thyrotropin-Releasing Hormone Receptor

    Science.gov (United States)

    Hinkle, Patricia M.; Gehret, Austin U.; Jones, Brian W.

    2012-01-01

    The pituitary receptor for thyrotropin-releasing hormone (TRH) is a calcium-mobilizing G protein-coupled receptor (GPCR) that signals through Gq/11, elevating calcium, and activating protein kinase C. TRH receptor signaling is quickly desensitized as a consequence of receptor phosphorylation, arrestin binding, and internalization. Following activation, TRH receptors are phosphorylated at multiple Ser/Thr residues in the cytoplasmic tail. Phosphorylation catalyzed by GPCR kinase 2 (GRK2) takes place rapidly, reaching a maximum within seconds. Arrestins bind to two phosphorylated regions, but only arrestin bound to the proximal region causes desensitization and internalization. Phosphorylation at Thr365 is critical for these responses. TRH receptors internalize in clathrin-coated vesicles with bound arrestin. Following endocytosis, vesicles containing phosphorylated TRH receptors soon merge with rab5-positive vesicles. Over approximately 20 min these form larger endosomes rich in rab4 and rab5, early sorting endosomes. After TRH is removed from the medium, dephosphorylated receptors start to accumulate in rab4-positive, rab5-negative recycling endosomes. The mechanisms responsible for sorting dephosphorylated receptors to recycling endosomes are unknown. TRH receptors from internal pools help repopulate the plasma membrane. Dephosphorylation of TRH receptors begins when TRH is removed from the medium regardless of receptor localization, although dephosphorylation is fastest when the receptor is on the plasma membrane. Protein phosphatase 1 is involved in dephosphorylation but the details of how the enzyme is targeted to the receptor remain obscure. It is likely that future studies will identify biased ligands for the TRH receptor, novel arrestin-dependent signaling pathways, mechanisms responsible for targeting kinases and phosphatases to the receptor, and principles governing receptor trafficking. PMID:23248581

  8. A model for short alpha-neurotoxin bound to nicotinic acetylcholine receptor from Torpedo californica.

    Science.gov (United States)

    Mordvintsev, Dmitry Y; Polyak, Yakov L; Kuzmine, Dmitry A; Levtsova, Olga V; Tourleigh, Yegor V; Kasheverov, Igor E

    2006-01-01

    Short- and long-chain alpha-neurotoxins from snake venoms are potent blockers of nicotinic acetylcholine receptors (nAChRs). Short alpha-neurotoxins consist of 60-62 amino acid residues and include 4 disulfide bridges, whereas long alpha-neurotoxins have 66-75 residues and 5 disulfides. The spatial structure of these toxins is built by three loops, I-III "fingers," confined by four disulfide bridges; the fifth disulfide of long-chain alpha-neurotoxins is situated close to the tip of central loop II. An accurate knowledge of the mode of alpha-neurotoxin-nAChR interaction is important for rational design of new nAChR agonists and antagonists for medical purposes. Ideas on the topography of toxin-nAChR complexes were based until recently on nAChR interactions with selectively labeled alpha-neurotoxins, mutations in toxins, nAChR, or both. Recently, crystal structures have been solved for the Torpedo marmorata nAChR (4A[Unwin, 2005]) and for the acetylcholine-binding protein (AChBP) complexed with mollusk alpha-conotoxin (2.4 A[Celie et al., 2005]) or alpha-cobratoxin, long-chain alpha-neurotoxin (4 A [Bourne et al., 2005]). However, there were no angstrom-resolution models for complexes of short-chain alpha-neurotoxins. Here, we report the model of the Torpedo californica nAChR extracellular domain complexed to a short-chain alpha-neurotoxin II (NTII) from Naja oxiana cobra venom.

  9. Activation of liver X receptor-alpha reduces activation of the renal and cardiac renin-angiotensin-aldosterone system

    NARCIS (Netherlands)

    Kuipers, Irma; van der Harst, Pim; Kuipers, Folkert; van Genne, Linda; Goris, Maaike; Lehtonen, Jukka Y.; van Veldhuisen, Dirk J.; van Gilst, Wiek H.; de Boer, Rudolf A.

    Liver X receptor (LXR)-alpha is a pivotal player in reverse cholesterol metabolism. Recently, LXR-alpha was implicated as an immediate regulator of renin expression in a cAMP-responsive manner. To determine whether long-term LXR-alpha activation affects activation of the renal and cardiac

  10. Appearance and cellular distribution of lectin-like receptors for alpha 1-acid glycoprotein in the developing rat testis

    DEFF Research Database (Denmark)

    Andersen, U O; Bøg-Hansen, T C; Kirkeby, S

    1996-01-01

    A histochemical avidin-biotin technique with three different alpha 1-acid glycoprotein glycoforms showed pronounced alterations in the cellular localization of two alpha 1-acid glycoprotein lectin-like receptors during cell differentiation in the developing rat testis. The binding of alpha 1-acid...

  11. Fatty Acid Amide Hydrolase (FAAH) Inhibition Enhances Memory Acquisition through Activation of PPAR-alpha Nuclear Receptors

    Science.gov (United States)

    Mazzola, Carmen; Medalie, Julie; Scherma, Maria; Panlilio, Leigh V.; Solinas, Marcello; Tanda, Gianluigi; Drago, Filippo; Cadet, Jean Lud; Goldberg, Steven R.; Yasar, Sevil

    2009-01-01

    Inhibitors of fatty acid amide hydrolase (FAAH) increase endogenous levels of anandamide (a cannabinoid CB[subscript 1]-receptor ligand) and oleoylethanolamide and palmitoylethanolamide (OEA and PEA, ligands for alpha-type peroxisome proliferator-activated nuclear receptors, PPAR-alpha) when and where they are naturally released in the brain.…

  12. Identification of alpha1-adrenergic receptors and their involvement in phosphoinositide hydrolysis in the frog heart.

    Science.gov (United States)

    Lazou, Antigone; Gaitanaki, Catherine; Vaxevanellis, Spiros; Pehtelidou, Anastasia

    2002-07-01

    The aim of this study was to characterize alpha(1)-adrenergic receptors in frog heart and to examine their related signal transduction pathway. alpha(1)-Adrenergic binding sites were studied in purified heart membranes using the specific alpha(1)-adrenergic antagonist [(3)H]prazosin. Analysis of the binding data indicated one class of binding sites displaying a K(d) of 4.19 +/- 0.56 nM and a B(max) of 14.66 +/- 1.61 fmol/mg original wet weight. Adrenaline, noradrenaline, or phenylephrine, in the presence of propranolol, competed with [(3)H]prazosin binding with a similar potency and a K(i) value of about 10 microM. The kinetics of adrenaline binding was closely related to its biological effect. Adrenaline concentration dependently increased the production of inositol phosphates in the heart in the presence or absence of propranolol. Maximal stimulation was about 8.5-fold, and the half-maximum effective concentration was 30 and 21 microM in the absence and presence of propranolol, respectively. These data clearly show that alpha(1)-adrenergic receptors are coupled to the phosphoinositide hydrolysis in frog heart. To our knowledge, this is the first direct evidence supporting the presence of functional alpha(1)-adrenergic receptors in the frog heart. Copyright 2002 Wiley-Liss, Inc.

  13. Domains of the growth hormone receptor required for association and activation of JAK2 tyrosine kinase

    DEFF Research Database (Denmark)

    VanderKuur, J A; Wang, X; Zhang, L

    1994-01-01

    Growth hormone (GH) has recently been shown to activate the GH receptor (GHR)-associated tyrosine kinase JAK2. In the present study, regions of the GHR required for JAK2 association with GHR were identified. GH-dependent JAK2 association with GHR was detected in Chinese hamster ovary (CHO) cells...

  14. Growth Hormone Receptor Signaling Pathways and its Negative Regulation by SOCS2

    DEFF Research Database (Denmark)

    Fernández Pérez, Leandro; Flores-Morales, Amilcar; Guerra, Borja

    2016-01-01

    Growth hormone (GH) is a critical regulator of linear body growth during childhood but continues to have important metabolic actions throughout life. The GH receptor (GHR) is ubiquitously expressed, and deficiency of GHR signaling causes a dramatic impact on normal physiology during somatic devel...

  15. Prognostic factors for survival in metastatic breast cancer by hormone receptor status

    NARCIS (Netherlands)

    Kwast, A.B.G.; Voogd, A.C.; Menke-Pluijmers, M.B.E.; Linn, S.C.; Sonke, G.S.; Kiemeney, L.A.; Siesling, Sabine

    2014-01-01

    Hormone receptor (HR) status is an important prognostic factor for patients with metastatic breast cancer (MBC) and is also correlated with other prognostic factors, such as initial lymph node status, HER2-Neu status and age. The prognostic value of these other factors, however, is unknown when

  16. Stress hormones and AMPA receptor trafficking in synaptic plasticity and memory

    NARCIS (Netherlands)

    Krugers, H.J.; Hoogenraad, C.C.; Groc, L.

    2010-01-01

    The acquisition and consolidation of memories of stressful events is modulated by glucocorticoids, a type of corticosteroid hormone that is released in high levels from the adrenal glands after exposure to a stressful event. These effects occur through activation of mineralocorticoid receptors (MRs)

  17. Structure and chromosomal localization of the human anti-mullerian hormone type II receptor gene

    NARCIS (Netherlands)

    J.A. Visser (Jenny); A. McLuskey; T. van Beers (T.); D.O. Weghuis (D. Olde); A.H.M. Geurts van Kessel (Ad); J.A. Grootegoed (Anton); A.P.N. Themmen (Axel)

    1995-01-01

    textabstractUsing the rat anti-müllerian hormone type II receptor (AMHRII) cDNA as a probe, two overlapping lambda phage clones containing the AMHRII gene were isolated from a human genomic library. Sequence analysis of the exons was performed and the exon/intron boundaries were determined. The

  18. Tc-99m-labeled RGD-conjugated alpha-melanocyte stimulating hormone hybrid peptides with reduced renal uptake.

    Science.gov (United States)

    Yang, Jianquan; Hu, Chien-An A; Miao, Yubin

    2015-04-01

    The purpose of this study was to examine whether the replacement of the positively-charged Lys or Arg linker with a neutral linker could reduce the renal uptake of Arg-Gly-Asp (RGD)-conjugated alpha-melanocyte stimulating hormone (α-MSH) hybrid peptide. The RGD motif {cyclic(Arg-Gly-Asp-DTyr-Asp)} was coupled to [Cys(3,4,10), D-Phe(7), Arg(11)]α-MSH3-13 {(Arg(11))CCMSH} through the neutral βAla or Ahx {aminohexanoic acid} linker (replacing the Lys or Arg linker) to generate novel RGD-βAla-(Arg(11))CCMSH and RGD-Ahx-(Arg(11))CCMSH hybrid peptides. The receptor-binding affinity and cytotoxicity of RGD-βAla-(Arg(11))CCMSH and RGD-Ahx-(Arg(11))CCMSH were determined in B16/F1 melanoma cells. The melanoma targeting and imaging properties of (99m)Tc-RGD-βAla-(Arg(11))CCMSH and (99m)Tc-RGD-Ahx-(Arg(11))CCMSH were determined in B16/F1 melanoma-bearing C57 mice. The replacement of the Lys or Arg linker with the βAla or Ahx linker retained nanomolar receptor-binding affinities and remarkable cytotoxicity of RGD-βAla-(Arg(11))CCMSH and RGD-Ahx-(Arg(11))CCMSH. The receptor-binding affinities of RGD-βAla-(Arg(11))CCMSH and RGD-Ahx-(Arg(11))CCMSH were 0.8 ± 0.05 and 1.3 ± 0.1 nM. Three-hour incubation with 0.1 µM of RGD-βAla-(Arg(11))CCMSH and RGD-Ahx-(Arg(11))CCMSH decreased the survival percentages of B16/F1 cells by 71 and 67 % as compared to the untreated control cells 5 days post the treatment. The replacement of the Arg linker with the βAla or Ahx linker reduced the non-specific renal uptake of (99m)Tc-RGD-βAla-(Arg(11))CCMSH and (99m)Tc-RGD-Ahx-(Arg(11))CCMSH by 62 and 61 % at 2 h post-injection. (99m)Tc-RGD-βAla-(Arg(11))CCMSH displayed higher melanoma uptake than (99m)Tc-RGD-Ahx-(Arg(11))CCMSH at 0.5, 2, 4, and 24 h post-injection. Enhanced tumor to kidney uptake ratio of (99m)Tc-RGD-βAla-(Arg(11))CCMSH warranted the further evaluation of (188)Re-labeled RGD-βAla-(Arg(11))CCMSH as a novel MC1 receptor-targeting therapeutic peptide for

  19. Disruption of glucagon receptor signaling causes hyperaminoacidemia exposing a possible liver - alpha-cell axis

    DEFF Research Database (Denmark)

    Galsgaard, Katrine D; Winther-Sørensen, Marie; Ørskov, Cathrine

    2018-01-01

    Glucagon secreted from the pancreatic alpha-cells is essential for regulation of blood glucose levels. However, glucagon may play an equally important role in the regulation of amino acid metabolism by promoting ureagenesis. We hypothesized that disruption of glucagon receptor signaling would lea...

  20. Two lectin-like receptors for alpha 1-acid glycoprotein in mouse testis

    DEFF Research Database (Denmark)

    Andersen, U O; Kirkeby, S; Bøg-Hansen, T C

    1997-01-01

    Three glycoforms of alpha 1-acid glycoprotein (AGP) were biotinylated to examine their binding in mouse testis by light microscopy. The transition from one stage to another in the spermatogenic cycle is marked with an appearance of a receptor for the Concanavalin A (Con A) non-reactive glycoform...

  1. Estrogen receptor-alpha-immunoreactive neurons in the periaqueductal gray of the adult ovariectomized female cat

    NARCIS (Netherlands)

    VanderHorst, Veronique G.J.M.; Meijer, Ellie; Schasfoort, Fabienne C.; Leeuwen, Fred van; Holstege, Gert

    1998-01-01

    Anatomical and physiological studies in rodent and cat have shown that distinct parts of the midbrain periaqueductal gray (FAG) are important for the estrogen dependent, female reproductive behavior. The present study gives a detailed overview of the estrogen receptor-alpha-immunoreactive (ER-IR)

  2. Inhibition of neointima formation by local delivery of estrogen receptor alpha and beta specific agonists

    NARCIS (Netherlands)

    Krom, Y.D.; Pires, N.M.M.; Jukema, J.W.; Vries, M.R. de; Frants, R.R.; Havekes, L.M.; Dijk, K.W. van; Quax, P.H.A.

    2007-01-01

    Objective: Neointima formation is the underlying mechanism of (in-stent) restenosis. 17β-Estradiol (E2) is known to inhibit injury-induced neointima formation and post-angioplasty restenosis. Estrogen receptor alpha (ERα) has been demonstrated to mediate E2 anti-restenotic properties. However, the

  3. Binding properties of solubilized gonadotropin-releasing hormone receptor: role of carboxylic groups

    Energy Technology Data Exchange (ETDEWEB)

    Hazum, E.

    1987-11-03

    The interaction of /sup 125/I-buserelin, a superactive agonist of gonadotropin-releasing hormone (GnRH), with solubilized GnRH receptor was studied. The highest specific binding of /sup 125/I-buserelin to solubilized GnRH receptor is evident at 4/sup 0/C, and equilibrium is reached after 2 h of incubation. The soluble receptor retained 100% of the original binding activity when kept at 4 or 22/sup 0/C for 60 min. Mono- and divalent cations inhibited, in a concentration-dependent manner, the binding of /sup 125/I-buserelin to solubilized GnRH receptor. Monovalent cations require higher concentrations than divalent cations to inhibit the binding. Since the order of potency with the divalent cations was identical with that of their association constants to dicarboxylic compounds, it is suggested that there are at least two carboxylic groups of the receptor that participate in the binding of the hormone. The carboxyl groups of sialic acid residues are not absolutely required for GnRH binding since the binding of /sup 125/I-buserelin to solubilized GnRH receptor was only slightly affected by pretreatment with neuraminidase and wheat germ agglutinin. The finding that polylysines stimulate luteinizing hormone (LH) release from pituitary cell cultures with the same efficacy as GnRH suggest that simple charge interactions can induce LH release. According to these results, the authors propose that the driving force for the formation of the hormone-receptor complex is an ionic interaction between the positively charged amino acid arginine in position 8 and the carboxyl groups in the binding site.

  4. DHEA metabolites activate estrogen receptors alpha and beta

    OpenAIRE

    Michael Miller, Kristy K.; Al-Rayyan, Numan; Ivanova, Margarita M.; Mattingly, Kathleen A.; Ripp, Sharon L.; KLINGE, CAROLYN M.; Prough, Russell A.

    2012-01-01

    Dehydroepiandrosterone (DHEA) levels were reported to associate with increased breast cancer risk in postmenopausal women, but some carcinogen-induced rat mammary tumor studies question this claim. The purpose of this study was to determine how DHEA and its metabolites affect estrogen receptors α or β (ERα or ERβ) -regulated gene transcription and cell proliferation. In transiently transfected HEK-293 cells, androstenediol, DHEA, and DHEA-S activated ERα. In ERβ transfected HepG2 cells, andro...

  5. Palmitoylation of interferon-alpha (IFN-alpha) receptor subunit IFNAR1 is required for the activation of Stat1 and Stat2 by IFN-alpha.

    Science.gov (United States)

    Claudinon, Julie; Gonnord, Pauline; Beslard, Emilie; Marchetti, Marta; Mitchell, Keith; Boularan, Cédric; Johannes, Ludger; Eid, Pierre; Lamaze, Christophe

    2009-09-04

    Type I interferons (IFNs) bind IFNAR receptors and activate Jak kinases and Stat transcription factors to stimulate the transcription of genes downstream from IFN-stimulated response elements. In this study, we analyze the role of protein palmitoylation, a reversible post-translational lipid modification, in the functional properties of IFNAR. We report that pharmacological inhibition of protein palmitoylation results in severe defects of IFN receptor endocytosis and signaling. We generated mutants of the IFNAR1 subunit of the type I IFN receptor, in which each or both of the two cysteines present in the cytoplasmic domain are replaced by alanines. We show that cysteine 463 of IFNAR1, the more proximal of the two cytoplasmic cysteines, is palmitoylated. A thorough microscopic and biochemical analysis of the palmitoylation-deficient IFNAR1 mutant revealed that IFNAR1 palmitoylation is not required for receptor endocytosis, intracellular distribution, or stability at the cell surface. However, the lack of IFNAR1 palmitoylation affects selectively the activation of Stat2, which results in a lack of efficient Stat1 activation and nuclear translocation and IFN-alpha-activated gene transcription. Thus, receptor palmitoylation is a previously undescribed mechanism of regulating signaling activity by type I IFNs in the Jak/Stat pathway.

  6. Growth hormone receptor deficiency (Laron syndrome) in black ...

    African Journals Online (AJOL)

    Non-Caucasians with growth honnone receptor (GHR) deficiency/Lamn syndrome among the approximately 180 recognised cases are rare, and include a Japanese and 3. African Americans. Black African siblings, a brother and a sister seen initially at 11 years 9 months and 5 years 6 months of age respectively were -7,4 ...

  7. Growth hormone receptor deficiency (Laron syndrome) in black ...

    African Journals Online (AJOL)

    Non-Caucasians with growth honnone receptor (GHR) deficiency/Lamn syndrome among the approximately 180 recognised cases are rare, and include a Japanese and 3 African Americans. Black African siblings, a brother and a sister seen initially at 11 years 9 months and 5 years 6 months of age respectively were -7,4 ...

  8. Loss of Trim24 (Tif1alpha) gene function confers oncogenic activity to retinoic acid receptor alpha.

    Science.gov (United States)

    Khetchoumian, Konstantin; Teletin, Marius; Tisserand, Johan; Mark, Manuel; Herquel, Benjamin; Ignat, Mihaela; Zucman-Rossi, Jessica; Cammas, Florence; Lerouge, Thierry; Thibault, Christelle; Metzger, Daniel; Chambon, Pierre; Losson, Régine

    2007-12-01

    Hepatocellular carcinoma (HCC) is a major cause of death worldwide. Here, we provide evidence that the ligand-dependent nuclear receptor co-regulator Trim24 (also known as Tif1alpha) functions in mice as a liver-specific tumor suppressor. In Trim24-null mice, hepatocytes fail to execute proper cell cycle withdrawal during the neonatal-to-adult transition and continue to cycle in adult livers, becoming prone to a continuum of cellular alterations that progress toward metastatic HCC. Using pharmacological approaches, we show that inhibition of retinoic acid signaling markedly reduces hepatocyte proliferation in Trim24-/- mice. We further show that deletion of a single retinoic acid receptor alpha (Rara) allele in a Trim24-null background suppresses HCC development and restores wild-type expression of retinoic acid-responsive genes in the liver, thus demonstrating that in this genetic background Rara expresses an oncogenic activity correlating with a dysregulation of the retinoic acid signaling pathway. Our results not only provide genetic evidence that Trim24 and Rara co-regulate hepatocarcinogenesis in an antagonistic manner but also suggest that aberrant activation of Rara is deleterious to liver homeostasis.

  9. Activation of the Torpedo nicotinic acetylcholine receptor. The contribution of residues alphaArg55 and gammaGlu93.

    Science.gov (United States)

    Kapur, Ankur; Davies, Martin; Dryden, William F; Dunn, Susan M J

    2006-03-01

    The Torpedo nicotinic acetylcholine receptor is a heteropentamer (alpha2betagammadelta) in which structurally homologous subunits assemble to form a central ion pore. Viewed from the synaptic cleft, the likely arrangement of these subunits is alpha-gamma-alpha-delta-beta lying in an anticlockwise orientation. High affinity binding sites for agonists and competitive antagonists have been localized to the alpha-gamma and alpha-delta subunit interfaces. We investigated the involvement of amino acids lying at an adjacent interface (gamma-alpha) in receptor properties. Recombinant Torpedo receptors, expressed in Xenopus oocytes, were used to investigate the consequences of mutating alphaArg55 and gammaGlu93, residues that are conserved in most species of the peripheral nicotinic receptors. Based on homology modeling, these residues are predicted to lie in close proximity to one another and it has been suggested that they may form a salt bridge in the receptor's three-dimensional structure (Sine et al. 2002 J Biol Chem277, 29 210-29 223). Although substitution of alphaR55 by phenylalanine or tryptophan resulted in approximately a six-fold increase in the EC50 value for acetylcholine activation, the charge reversal mutation (alphaR55E) had no significant effect. In contrast, the replacement of gammaE93 by an arginine conferred an eight-fold increase in the potency for acetylcholine-induced receptor activation. In the receptor carrying the double mutations, alphaR55E-gammaE93R or alphaR55F-gammaE93R, the potency for acetylcholine activation was partially restored to that of the wild-type. The results suggest that, although individually these residues influence receptor activation, direct interactions between them are unlikely to play a major role in the stabilization of different conformational states of the receptor.

  10. Ontogenic increase in PGE2 and PGF2 alpha receptor density in brain microvessels of pigs.

    Science.gov (United States)

    Li, D. Y.; Varma, D. R.; Chemtob, S.

    1994-01-01

    1. The hypothesis that the relative vasoconstrictor ineffectiveness of prostaglandin E2 (PGE2) and PGF2 alpha on cerebral vessels of newborn pigs might be due to fewer receptors for these prostanoids was tested by comparing receptors for PGE2 (EP) and PGF2 alpha (FP) in cerebral microvessels from newborn and adult pigs. 2. Specific binding of [3H]-PGE2 and [3H]-PGF2 alpha to membranes prepared from brain microvessels showed that EP and FP receptor density (Bmax) in tissues from newborn animals was less than 50% of that determined in tissues from adults. By contrast, estimates of affinity (KD) were unchanged. 3. Specifically bound [3H]-PGE2 to brain microvessels from both the newborn and adult was displaced by AH 6809 (EP1-selective antagonist) by 80-90%, and only by approximately 30-35% by both 11-deoxy PGE1 (EP2/EP3 agonist) and M&B 28,767 (EP3 agonist); butaprost (EP2 agonist) was completely ineffective. 4. PGE2, 17-phenyl trinor PGE2 (EP1 agonist), PGF2 alpha and fenprostalene (PGF2 alpha analogue) caused significantly less increase in inositol 1,4,5-triphosphate (IP3) in brain microvessels from the newborn than in those from adult pigs. The stimulation of IP3 by PGE2 and 17-phenyl trinor PGE2 was almost completely inhibited by the EP1 antagonist, AH 6809. 5. PGE2, 11-deoxy PGE1 and M&B 28,767 produced small reduction of adenosine 3':5'-cyclic monophosphate (cyclic AMP) production in adult vessels but no effect in newborn tissues. 6. The lower density of EP and FP receptors in microvessels of newborn pigs compared to adults may explain the reduced ability of PGE2 and PGF2 alpha to stimulate production of IP3 in tissues from newborn animals.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8032662

  11. Alpha-melanocyte-stimulating hormone attenuates behavioral effects of corticotropin-releasing factor in isolated guinea pig pups.

    Science.gov (United States)

    Schiml-Webb, Patricia A; Miller, Emily; Deak, Terrence; Hennessy, Michael B

    2009-07-01

    During a 3-hr period of social isolation in a novel environment, guinea pig pups exhibit an initial active phase of behavioral responsiveness, characterized primarily by vocalizing, which is then followed by a stage of passive responsiveness in which pups display a distinctive crouch, eye-closing, and extensive piloerection. Prior treatment of pups with alpha-melanocyte-stimulating hormone (alpha-MSH) reduces each of the passive behaviors. The onset of passive responding during separation can be accelerated with peripheral injection of corticotropin-releasing factor (CRF). To examine whether CRF produces its effects through a mechanism similar to that of prolonged separation, we examined the effect of administering alpha-MSH to pups injected with CRF. As expected, CRF markedly enhanced passive responding during a 60-min period of separation. alpha-MSH delivered by either intracerebroventricular infusion or intraperitoneal injection significantly reduced each of the passive behavioral responses without significantly affecting active behavior. These findings, together with previous results indicating that it is the anti-inflammatory property of alpha-MSH that is responsible for its behavioral effects during prolonged separation, suggest that peripheral CRF speeds the induction of passive responding through a mechanism involving enhanced proinflammatory activity.

  12. Thyroid Hormone Receptors Predict Prognosis in BRCA1 Associated Breast Cancer in Opposing Ways

    Science.gov (United States)

    Heublein, Sabine; Mayr, Doris; Meindl, Alfons; Angele, Martin; Gallwas, Julia; Jeschke, Udo; Ditsch, Nina

    2015-01-01

    Since BRCA1 associated breast cancers are frequently classified as hormone receptor negative or even triple negative, the application of endocrine therapies is rather limited in these patients. Like hormone receptors that bind to estrogen or progesterone, thyroid hormone receptors (TRs) are members of the nuclear hormone receptor superfamily. TRs might be interesting biomarkers - especially in the absence of classical hormone receptors. The current study aimed to investigate whether TRs may be specifically expressed in BRCA1 associated cancer cases and whether they are of prognostic significance in these patients as compared to sporadic breast cancer cases. This study analyzed TRα and TRβ immunopositivity in BRCA1 associated (n = 38) and sporadic breast cancer (n = 86). Further, TRs were studied in MCF7 (BRCA1 wildtype) and HCC3153 (BRCA1 mutated) cells. TRβ positivity rate was significantly higher in BRCA1 associated as compared to sporadic breast cancers (p = 0.001). The latter observation remained to be significant when cases that had been matched for clinicopathological criteria were compared (p = 0.037). Regarding BRCA1 associated breast cancer cases TRβ positivity turned out to be a positive prognostic factor for five-year (p = 0.007) and overall survival (p = 0.026) while TRα positivity predicted reduced five-year survival (p = 0.030). Activation of TRβ resulted in down-modulation of CTNNB1 while TRα inhibition reduced cell viability in HCC3153. However, only BRCA1 wildtype MCF7 cells were capable of rapidly degrading TRα1 in response to T3 stimulation. Significantly, this study identified TRβ to be up-regulated in BRCA1 associated breast cancer and revealed TRs to be associated with patients’ prognosis. TRs were also found to be expressed in triple negative BRCA1 associated breast cancer. Further studies need to be done in order to evaluate whether TRs may become interesting targets of endocrine therapeutic approaches, especially when tumors are

  13. Thyroid Hormone Receptors Predict Prognosis in BRCA1 Associated Breast Cancer in Opposing Ways.

    Directory of Open Access Journals (Sweden)

    Sabine Heublein

    Full Text Available Since BRCA1 associated breast cancers are frequently classified as hormone receptor negative or even triple negative, the application of endocrine therapies is rather limited in these patients. Like hormone receptors that bind to estrogen or progesterone, thyroid hormone receptors (TRs are members of the nuclear hormone receptor superfamily. TRs might be interesting biomarkers - especially in the absence of classical hormone receptors. The current study aimed to investigate whether TRs may be specifically expressed in BRCA1 associated cancer cases and whether they are of prognostic significance in these patients as compared to sporadic breast cancer cases. This study analyzed TRα and TRβ immunopositivity in BRCA1 associated (n = 38 and sporadic breast cancer (n = 86. Further, TRs were studied in MCF7 (BRCA1 wildtype and HCC3153 (BRCA1 mutated cells. TRβ positivity rate was significantly higher in BRCA1 associated as compared to sporadic breast cancers (p = 0.001. The latter observation remained to be significant when cases that had been matched for clinicopathological criteria were compared (p = 0.037. Regarding BRCA1 associated breast cancer cases TRβ positivity turned out to be a positive prognostic factor for five-year (p = 0.007 and overall survival (p = 0.026 while TRα positivity predicted reduced five-year survival (p = 0.030. Activation of TRβ resulted in down-modulation of CTNNB1 while TRα inhibition reduced cell viability in HCC3153. However, only BRCA1 wildtype MCF7 cells were capable of rapidly degrading TRα1 in response to T3 stimulation. Significantly, this study identified TRβ to be up-regulated in BRCA1 associated breast cancer and revealed TRs to be associated with patients' prognosis. TRs were also found to be expressed in triple negative BRCA1 associated breast cancer. Further studies need to be done in order to evaluate whether TRs may become interesting targets of endocrine therapeutic approaches, especially when

  14. 17 alpha-substituted analogs of estradiol for the development of fluorescent estrogen receptor ligands.

    Science.gov (United States)

    Salman, M; Reddy, B R; Delgado, P; Stotter, P L; Fulcher, L C; Chamness, G C

    1991-07-01

    For the successful development of a high-affinity fluorophore-estradiol conjugate, the fluorophore must be attached to the estradiol molecule at a position that interferes least with its binding to the receptor. We have concentrated on 17 alpha substituents as models for fluorophore attachment, based on literature precedent and on our earlier work with small 17 alpha side chains. In this report, we describe syntheses and estrogen receptor binding affinities of 19 analogs of estradiol substituted in the 17 alpha position with larger side chains (of six to 11 carbons), some of which may be synthetically modified to link a fluorophore. These analogs were synthesized either by nucleophilic cleavage of estrone-17 beta-oxirane 3-benzyl ether and subsequent debenzylation (4 to 18), by cross-coupling of alkynes (21 to 24), by alkylation of 17 alpha-ethynylestradiol 3,17-bis(tetrahydropyranyl ether) and subsequent acidic hydrolysis (25 to 28), or by reacting estrone either with appropriate aryl/alkynyllithium reagents (29, 30, and 32) or with benzylmagnesium bromide (31). Relative binding affinities of these newly synthesized analogs were determined for estrogen receptor (rat uterus) using a standard competition assay. The results suggest that analogs with reduced mobility and/or more polarizable electron density in the side chain generally bind more strongly to the receptor. The relative affinities of several selected compounds were also determined in the presence of 4% dimethylformamide; some compounds bearing larger, nonpolar 17 alpha substituents showed dramatically improved affinities, while affinities for compounds with shorter nonpolar side chains remained largely unchanged. These binding affinity results should be useful in designing new high-affinity fluorescent ligands for the estrogen receptor.

  15. The neuronal nicotinic alpha4beta2 receptor has a high maximal probability of being open.

    Science.gov (United States)

    Li, Ping; Steinbach, Joe H

    2010-08-01

    A fundamental property of transmitter-gated ion channels is the probability a channel will be open (P(open)) when stimulated by a concentration of agonist that elicits a maximal response. This value is critical for interpreting steady-state concentration-response relationships in terms of channel activation, and for understanding the actions of drugs that potentiate responses. We used analysis of non-stationary noise to estimate the maximal probability the nicotinic alpha4beta2 receptor is open. HEK293 cells stably transfected to express human alpha4beta2 nicotinic receptors were studied using whole-cell voltage clamp. Nicotinic agonists (acetylcholine, nicotine, cytisine and 5-iodo A-85380) were applied, and the relationship between variance of the elicited whole-cell current and mean current was analysed. The variance did not increase linearly with the mean current. For acetylcholine and nicotine the relationship between variance and mean indicates that the maximal P(open) is greater than 0.8. The number of agonist-activatable channels was estimated to be about 1000 per cell. The mean single channel conductance at -60 mV was indistinguishable when currents were elicited by acetylcholine (18 pS), nicotine (17 pS) or 5-iodo A-85380 (17 pS), whereas the value for cytisine was larger (24 pS). The neuronal nicotinic alpha4beta2 receptor has a maximal probability of being open that is greater than 0.8. This conclusion applies to the receptor containing three alpha4 and two beta2 subunits (the low-sensitivity stoichiometry), but may not apply to the receptor containing two alpha4 and three beta2 subunits (the high-sensitivity stoichiometry).

  16. Occurrence of xenobiotic ligands for retinoid X receptors and thyroid hormone receptors in the aquatic environment of Taiwan.

    Science.gov (United States)

    Chen, Chien-Hsun; Chou, Pei-Hsin; Kawanishi, Masanobu; Yagi, Takashi

    2014-08-30

    Various synthetic compounds are frequently discharged into the environment via human activities. Among them, certain contaminants may disrupt normal physiological functions of wildlife and humans via interactions with nuclear receptors. To protect human health and the environment, it is important to detect environmental ligands for human nuclear receptors. In this study, yeast-based reporter gene assays were used to investigate the occurrence of xenobiotic ligands for retinoid X receptors (RXR) and thyroid hormone receptors (TR) in the aquatic environment of Taiwan. Experimental results revealed that RXR agonist/antagonist activity was detected in river water and sediment samples. In particular, high RXR agonist/antagonist activity was found in the samples collected near river mouths. Additionally, few samples also elicited significant TR antagonist activity. Our findings show that the aquatic environment of Taiwan was contaminated with RXR and TR ligands. Further study is necessary to identify these xenobiotic RXR and TR agonists and antagonists. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Alpha-thujone reduces 5-HT3 receptor activity by an effect on the agonist-reduced desensitization.

    Science.gov (United States)

    Deiml, T; Haseneder, R; Zieglgänsberger, W; Rammes, G; Eisensamer, B; Rupprecht, R; Hapfelmeier, G

    2004-02-01

    The convulsant effects of alpha-thujone, the psychotropic component of absinthe, were attributed to inhibitory actions at the GABAA receptor. Here, we investigated for the first time the 5-HT3 receptor as a potential site of the psychotropic actions of alpha-thujone. This cation permeable ligand-gated ion channel shows considerable homology to the GABAA receptor. We previously demonstrated that in homomeric assemblies of cloned human 5-HT,A receptor subunits. the endogenous agonist 5-HT induced desensitization via channel blockade. When the 5-HT3 B receptor subunit was co-expressed, the resulting heteromeric assemblies desensitized independent from channel blockade. In the present study, patch-clamp experiments revealed an inhibitory action of alpha-thujone on both homomeric and heteromeric 5-HT3 receptors. This inhibitory action was mediated via channel blockade. However, it was not alpha-thujone itself which blocked the channel. The present experiments suggested that, in homomeric receptors, alpha-thujone enhanced the inherent channel-blocking potency of the natural ligand. 5-HT. In heteromeric receptors, alpha-thujonerecruited an additional channel-blocking component of the agonist. By means of kinetic modeling, we simulated possible mechanisms by which alpha-thuljone decreased the 5-HT-induced responses. It is suggested that alpha-thujone reduced 5-HT3 receptor activity by an effect on mechanisms involved in receptor desensitization, which depend on receptor subunit composition. It remains to be shown if this inhibitory action on serotonergic responses contributes to behavioral effects of alpha-thujone.

  18. The Parathyroid Hormone Family of Ligands and Receptors

    Directory of Open Access Journals (Sweden)

    Damian G. D'Souza

    2015-07-01

    Full Text Available The PTH family of ligands and receptors have a wide range of vital functions from calcium homeostasis to tissue and bone development from the embryo to adult. This family has undergone whole genome duplication events predating vertebrate evolution, indicating more primitive and ancient functions other than skeletal development. The N-terminal region of the ligands, have been widely studied by biophysical and functional analysis, resulting in the discovery of key characteristics essential for ligand-receptor activation being elucidated. Multi-substituted amino acid analogs with differential binding affinities and either antagonistic or agonistic signalling potencies have been created based on these findings allowing for improvement on potential therapies affected by the PTH system in skeletal and embryonic development. The PTH family has diversely evolved to cover a wide range of pivotal pathways crucial to growth and development throughout all animal life.

  19. Structure-activity analysis of synthetic alpha-thrombin-receptor-activating peptides.

    Science.gov (United States)

    Van Obberghen-Schilling, E; Rasmussen, U B; Vouret-Craviari, V; Lentes, K U; Pavirani, A; Pouysségur, J

    1993-06-15

    alpha-Thrombin stimulates G-protein-coupled effectors leading to secretion and aggregation in human platelets, and to a mitogenic response in CCL39 hamster fibroblasts. alpha-Thrombin receptors can be activated by synthetic peptides corresponding to the receptor sequence starting with serine-42, at the proposed cleavage site. We have previously determined that the agonist domain of receptor-activating peptides resides within the five N-terminal residues [Vouret-Craviari, Van Obberghen-Schilling, Rasmussen, Pavirani, Lecocq and Pouysségur (1992) Mol. Biol. Cell. 3, 95-102], although the 7-residue peptide (SFFLRNP) corresponding to the hamster alpha-thrombin receptor was 10 times more potent than the 5-residue peptide for activation of human platelets. In the present study we have analysed the role of individual amino acids in receptor activation by using a series of modified hexa- or hepta-peptides derived from the human alpha-thrombin-receptor sequence. Cellular events examined here include phospholipase C activation, adenylyl cyclase inhibition and DNA synthesis stimulation in non-transformed CCL39 fibroblasts and a tumorigenic variant of that line (A71 cells). Modification of the peptide sequence had similar functional consequence for each of the assays described, indicating that either a unique receptor or pharmacologically indistinguishable receptor subtypes activate distinct G-protein signalling pathways. Furthermore, we found that: (1) the N-terminal serine can be replaced by small or intermediately sized amino acids (+/- hydroxyl groups) without loss of activity. However, its replacement by an aromatic side-chain or omission of the N-terminal amino group severely reduces activity. (2) An aromatic side-chain on the penultimate N-terminal residue appears to play a critical role since phenylalanine in this position can be substituted by tyrosine without complete loss of activity whereas an alanine in its place is not tolerated. (3) Deletion of the first

  20. DHEA metabolites activate estrogen receptors alpha and beta

    Science.gov (United States)

    Michael Miller, Kristy K.; Al-Rayyan, Numan; Ivanova, Margarita M.; Mattingly, Kathleen A.; Ripp, Sharon L.; Klinge, Carolyn M.; Prough, Russell A.

    2012-01-01

    Dehydroepiandrosterone (DHEA) levels were reported to associate with increased breast cancer risk in postmenopausal women, but some carcinogen-induced rat mammary tumor studies question this claim. The purpose of this study was to determine how DHEA and its metabolites affect estrogen receptors α or β (ERα or ERβ) -regulated gene transcription and cell proliferation. In transiently transfected HEK-293 cells, androstenediol, DHEA, and DHEA-S activated ERα. In ERβ transfected HepG2 cells, androstenedione, DHEA, androstenediol, and 7-oxo DHEA stimulated reporter activity. ER antagonists ICI 182,780 (fulvestrant) and 4-hydroxytamoxifen, general P450 inhibitor miconazole, and aromatase inhibitor exemestane inhibited activation by DHEA or metabolites in transfected cells. ERβ-selective antagonist R,R-THC (R,R-cis-diethyl tetrahydrochrysene) inhibited DHEA and DHEA metabolite transcriptional activity in ERβ-transfected cells. Expression of endogenous estrogen-regulated genes: pS2, progesterone receptor, cathepsin D1, and nuclear respiratory factor-1 was increased by DHEA and its metabolites in an ER-subtype, gene, and cell-specific manner. DHEA metabolites, but not DHEA, competed with 17β-estradiol for ERα and ERβ binding and stimulated MCF-7 cell proliferation, demonstrating that DHEA metabolites interact directly with ERα and ERβ in vitro, modulating estrogen target genes in vivo. PMID:23123738

  1. Melanin-concentrating hormone and its receptors: state of the art.

    Science.gov (United States)

    Boutin, Jean A; Suply, Thomas; Audinot, Valérie; Rodriguez, Marianne; Beauverger, Philippe; Nicolas, Jean-Paul; Galizzi, Jean-Pierre; Fauchère, Jean-Luc

    2002-05-01

    Melanin-concentrating hormone (MCH) is a cyclic neuropeptide of nineteen amino acids in mammals. Its involvement in the feeding behaviour has been well established during the last few years. A first receptor subtype, now termed MCHIR, was discovered in 1999, following the desorphanisation of the SLCI orphan receptor, using either reverse pharmacology or systematic screening of agonist candidates. A second MCH receptor, MCH2R, has been discovered recently, by several groups working on data mining of genomic banks. The molecular pharmacology of these two receptors is only described on the basis of the action of peptides derived from MCH. The present review tentatively summarizes the knowledge on these two receptors and presents the first attempts to discover new classes of antagonists that might have major roles in the control of obesity and feeding behaviour.

  2. Interaction between retinoid acid receptor-related orphan receptor alpha (RORA) and neuropeptide S receptor 1 (NPSR1) in asthma.

    Science.gov (United States)

    Acevedo, Nathalie; Sääf, Annika; Söderhäll, Cilla; Melén, Erik; Mandelin, Jami; Pietras, Christina Orsmark; Ezer, Sini; Karisola, Piia; Vendelin, Johanna; Gennäs, Gustav Boije af; Yli-Kauhaluoma, Jari; Alenius, Harri; von Mutius, Erika; Doekes, Gert; Braun-Fahrländer, Charlotte; Riedler, Josef; van Hage, Marianne; D'Amato, Mauro; Scheynius, Annika; Pershagen, Göran; Kere, Juha; Pulkkinen, Ville

    2013-01-01

    Retinoid acid receptor-related Orphan Receptor Alpha (RORA) was recently identified as a susceptibility gene for asthma in a genome-wide association study. To investigate the impact of RORA on asthma susceptibility, we performed a genetic association study between RORA single nucleotide polymorphisms (SNPs) in the vicinity of the asthma-associated SNP (rs11071559) and asthma-related traits. Because the regulatory region of a previously implicated asthma susceptibility gene, Neuropeptide S receptor 1 (NPSR1), has predicted elements for RORA binding, we hypothesized that RORA may interact biologically and genetically with NPSR1. 37 RORA SNPs and eight NPSR1 SNPs were genotyped in the Swedish birth cohort BAMSE (2033 children) and the European cross-sectional PARSIFAL study (1120 children). Seven RORA SNPs confined into a 49 kb region were significantly associated with physician-diagnosed childhood asthma. The most significant association with rs7164773 (T/C) was driven by the CC genotype in asthma cases (OR = 2.0, 95%CI 1.36-2.93, p = 0.0003 in BAMSE; and 1.61, 1.18-2.19, p = 0.002 in the combined BAMSE-PARSIFAL datasets, respectively), and strikingly, the risk effect was dependent on the Gln344Arg mutation in NPSR1. In cell models, stimulation of NPSR1 activated a pathway including RORA and other circadian clock genes. Over-expression of RORA decreased NPSR1 promoter activity further suggesting a regulatory loop between these genes. In addition, Rora mRNA expression was lower in the lung tissue of Npsr1 deficient mice compared to wildtype littermates during the early hours of the light period. We conclude that RORA SNPs are associated with childhood asthma and show epistasis with NPSR1, and the interaction between RORA and NPSR1 may be of biological relevance. Combinations of common susceptibility alleles and less common functional polymorphisms may modify the joint risk effects on asthma susceptibility.

  3. Interaction between retinoid acid receptor-related orphan receptor alpha (RORA and neuropeptide S receptor 1 (NPSR1 in asthma.

    Directory of Open Access Journals (Sweden)

    Nathalie Acevedo

    Full Text Available Retinoid acid receptor-related Orphan Receptor Alpha (RORA was recently identified as a susceptibility gene for asthma in a genome-wide association study. To investigate the impact of RORA on asthma susceptibility, we performed a genetic association study between RORA single nucleotide polymorphisms (SNPs in the vicinity of the asthma-associated SNP (rs11071559 and asthma-related traits. Because the regulatory region of a previously implicated asthma susceptibility gene, Neuropeptide S receptor 1 (NPSR1, has predicted elements for RORA binding, we hypothesized that RORA may interact biologically and genetically with NPSR1. 37 RORA SNPs and eight NPSR1 SNPs were genotyped in the Swedish birth cohort BAMSE (2033 children and the European cross-sectional PARSIFAL study (1120 children. Seven RORA SNPs confined into a 49 kb region were significantly associated with physician-diagnosed childhood asthma. The most significant association with rs7164773 (T/C was driven by the CC genotype in asthma cases (OR = 2.0, 95%CI 1.36-2.93, p = 0.0003 in BAMSE; and 1.61, 1.18-2.19, p = 0.002 in the combined BAMSE-PARSIFAL datasets, respectively, and strikingly, the risk effect was dependent on the Gln344Arg mutation in NPSR1. In cell models, stimulation of NPSR1 activated a pathway including RORA and other circadian clock genes. Over-expression of RORA decreased NPSR1 promoter activity further suggesting a regulatory loop between these genes. In addition, Rora mRNA expression was lower in the lung tissue of Npsr1 deficient mice compared to wildtype littermates during the early hours of the light period. We conclude that RORA SNPs are associated with childhood asthma and show epistasis with NPSR1, and the interaction between RORA and NPSR1 may be of biological relevance. Combinations of common susceptibility alleles and less common functional polymorphisms may modify the joint risk effects on asthma susceptibility.

  4. Alpha/sub 1/ receptor coupling events initiated by methoxy-substituted tolazoline partial agonists

    Energy Technology Data Exchange (ETDEWEB)

    Wick, P.; Keung, A.; Deth, R.

    1986-03-01

    A series of mono- and dimethyoxy substituted tolazoline derivatives, known to be partial agonists at the alpha/sub 1/ receptor, were compared with the ..cap alpha../sub 1/ selective full agonist phenylephrine (PE) on isolated strips of rabbit aorta Agonist activity was evaluated in contraction, /sup 45/Ca influx, /sup 45/Ca efflux, and /sup 32/P-Phospholipid labelling studies. Maximum contractile responses for the 2-, 3-, and 3, 5- methoxy substituted tolazoline derivatives (10/sup -5/M) were 53.8, 67.6 and 99.7% of the PE (10/sup -5/M) response respectively. These same partial agonists caused a stimulation of /sup 45/Ca influx to the extent of 64, 86, and 95% of the PE response respectively. In /sup 45/Ca efflux studies, (a measure of the intracellular Ca/sup +2/ release) the tolazolines caused: 30%, 63%, and 78% of the PE stimulated level. /sup 32/P-Phosphatidic acid (PA) labelling was measured as an index of PI turnover after ..cap alpha../sub 1/ receptor stimulation. Compared to PE, the 2-, 3-, and 3,5- methoxy substituted tolazoline derivatives caused 22, 46, and 72% PA labelling. The above values are all in reasonable accord with the rank order or agonist activity shown in maximum contractile responses. The results of this investigation suggest that partial agonists stimulate ..cap alpha.. receptor coupling events at a level which is quantitatively comparable to their potencies in causing contraction of arterial smooth muscle.

  5. Polymorphism of growth hormone receptor (GHR gene in Holstein Friesian dairy cattle

    Directory of Open Access Journals (Sweden)

    Restu Misrianti

    2011-12-01

    Full Text Available Growth hormone gene have a critical role in the regulation of lactation, mammary gland development and growth process through its interaction with a specific receptor. Growth hormone (GH is an anabolic hormone which is synthesized and secreted by somatotrop cell in pituitary anterior lobe, and interacts with a specific receptor on the surface of the target cells. Growth hormone receptor (GHR has been suggested as candidate gene for traits related to milk production in Bovidae. The purpose of this study was to identify genetic polymorphism of the Growth Hormone Receptor (GHR genes in Holstein Friesian (HF cattle. Total of 353 blood samples were collected from five populations belonging to Cikole Dairy Cattle Breeding Station (BPPT-SP Cikole (88 samples, Pasir Kemis (95 samples, Cilumber (98 samples, Cipelang Livestock Embryo Center (BET Cipelang (40 samples, Singosari National Artificial Insemination Centre (BBIB Singosari (32 samples and 17 frozen semen samples from Lembang Artificial Insemination Center (BIB Lembang. Genomic DNAs were extracted by a standard phenol-chloroform protocol and amplified by a polymerase chain reaction (PCR techniques then PCR products were genotyped by the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP methods. There were two allele dan three genotypes were found namely: allele A and G, Genotype AA, AG and GG repectively. Allele A frequency (0.70-0.82 relatively higher than allele G frequency (0.18-0.30. Chi square test show that on group of BET Cipelang, BIB Lembang and BBIB Singosari population were not significantly different (0.00-0.93, while on group of BET Cipelang, BIB Lembang dan BBIB Singosari population were significantly different (6.02-11.13. Degree of observed heterozygosity (Ho ranged from 0.13-0.42 and expected heterozygosity (He ranged from 0.29-0.42.

  6. Activation of Peroxisome Proliferator-Activated Receptor Alpha Improves Aged and UV-Irradiated Skin by Catalase Induction.

    Science.gov (United States)

    Shin, Mi Hee; Lee, Se-Rah; Kim, Min-Kyoung; Shin, Chang-Yup; Lee, Dong Hun; Chung, Jin Ho

    2016-01-01

    Peroxisome proliferator-activated receptor alpha (PPARα) is a nuclear hormone receptor involved in the transcriptional regulation of lipid metabolism, fatty acid oxidation, and glucose homeostasis. Its activation stimulates antioxidant enzymes such as catalase, whose expression is decreased in aged human skin. Here we investigated the expression of PPARα in aged and ultraviolet (UV)-irradiated skin, and whether PPARα activation can modulate expressions of matrix metalloproteinase (MMP)-1 and procollagen through catalase regulation. We found that PPARα mRNA level was significantly decreased in intrinsically aged and photoaged human skin as well as in UV-irradiated skin. A PPARα activator, Wy14643, inhibited UV-induced increase of MMP-1 and decrease of procollagen expression and caused marked increase in catalase expression. Furthermore, production of reactive oxygen species (ROS) was suppressed by Wy14643 in UV-irradiated and aged dermal fibroblasts, suggesting that the PPARα activation-induced upregulation of catalase leads to scavenging of ROS produced due to UV irradiation or aging. PPARα knockdown decreased catalase expression and abolished the beneficial effects of Wy14643. Topical application of Wy14643 on hairless mice restored catalase activity and prevented MMP-13 and inflammatory responses in skin. Our findings indicate that PPARα activation triggers catalase expression and ROS scavenging, thereby protecting skin from UV-induced damage and intrinsic aging.

  7. The effect of a metalloproteinase inhibitor (GI5402) on tumor necrosis factor-alpha (TNF-alpha) and TNF-alpha receptors during human endotoxemia

    NARCIS (Netherlands)

    Dekkers, P. E.; Lauw, F. N.; ten Hove, T.; te Velde, A. A.; Lumley, P.; Becherer, D.; van Deventer, S. J.; van der Poll, T.

    1999-01-01

    Tumor necrosis factor-alpha (TNF-alpha) is released from the cell surface by cleavage of pro-TNF-alpha by metalloproteinases (MPs). In cell cultures, inhibition of MPs has been found not only to reduce the release of TNF-alpha, but also to enhance the surface expression of TNF-alpha and TNF-alpha

  8. Catalposide is a natural agonistic ligand of peroxisome proliferator-activated receptor-{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Hae; Jun, Hee-jin; Hoang, Minh-Hien; Jia, Yaoyao [Division of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of); Department of Biotechnology, Graduate School of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of); Han, Xiang Hua [College of Pharmacy, Chungbuk National University, Cheongju, Chungbuk 361-763 (Korea, Republic of); Lee, Dong-Ho [Department of Biotechnology, Graduate School of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of); Lee, Hak-Ju [Division of Green Business Management, Department of Forest Resources Utilization, Korean Forest Research Institute, Seoul 130-712 (Korea, Republic of); Hwang, Bang Yeon, E-mail: byhwang@chungbuk.ac.kr [College of Pharmacy, Chungbuk National University, Cheongju, Chungbuk 361-763 (Korea, Republic of); Lee, Sung-Joon, E-mail: junelee@korea.ac.kr [Division of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of); Department of Biotechnology, Graduate School of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer Catalposide is a novel ligand for PPAR{alpha}. Black-Right-Pointing-Pointer Cell stimulated with catalposide improved fatty acid uptake, regulated target genes in fatty acid {beta}-oxidation and synthesis. Black-Right-Pointing-Pointer Catalposdie reduces hepatic triacylglycerides. Black-Right-Pointing-Pointer Theses demonstrate catalposide could ameliorate hyperlipidemia and hepatic steatosis. -- Abstract: Peroxisome proliferator-activated receptor-alpha (PPAR{alpha}) is a nuclear receptor that regulates the expression of genes related to cellular lipid uptake and oxidation. Thus, PPAR{alpha} agonists may be important in the treatment of hypertriglyceridemia and hepatic steatosis. In this study, we demonstrated that catalposide is a novel natural PPAR{alpha} agonist, identified from reporter gene assay-based activity screening with approximately 900 natural plant and seaweed extracts. Results of time-resolved fluorescence resonance energy transfer analyses suggested that the compound interacted directly with the ligand-binding domain of PPAR{alpha}. Cultured hepatocytes stimulated with catalposide exhibited significantly reduced cellular triglyceride concentrations, by 21%, while cellular uptake of fatty acids was increased, by 70% (P < 0.05). Quantitative PCR analysis revealed that the increase in cellular fatty acid uptake was due to upregulation of fatty acid transporter protein-4 (+19% vs. the control) in cells stimulated with catalposide. Additionally, expression of genes related to fatty acid oxidation and high-density lipoprotein metabolism were upregulated, while that of genes related to fatty acid synthesis were suppressed. In conclusion, catalposide is hypolipidemic by activation of PPAR{alpha} via a ligand-mediated mechanism that modulates the expression of in lipid metabolism genes in hepatocytes.

  9. Folate Receptor Targeted Alpha-Therapy Using Terbium-149

    CERN Document Server

    Müller, Cristina; Haller, Stephanie; Dorrer, Holger; Köster, Ulli; Johnston, Karl; Zhernosekov, Konstantin; Türler, Andreas; Schibli, Roger

    2014-01-01

    Terbium-149 is among the most interesting therapeutic nuclides for medical applications. It decays by emission of short-range α-particles (Eα = 3.967 MeV) with a half-life of 4.12 h. The goal of this study was to investigate the anticancer efficacy of a 149Tb-labeled DOTA-folate conjugate (cm09) using folate receptor (FR)-positive cancer cells in vitro and in tumor-bearing mice. 149Tb was produced at the ISOLDE facility at CERN. Radiolabeling of cm09 with purified 149Tb resulted in a specific activity of ~1.2 MBq/nmol. In vitro assays performed with 149Tb-cm09 revealed a reduced KB cell viability in a FR-specific and activity concentration-dependent manner. Tumor-bearing mice were injected with saline only (group A) or with 149Tb-cm09 (group B: 2.2 MBq; group C: 3.0 MBq). A significant tumor growth delay was found in treated animals resulting in an increased average survival time of mice which received 149Tb-cm09 (B: 30.5 d; C: 43 d) compared to untreated controls (A: 21 d). Analysis of blood parameters rev...

  10. Alpha-Bulges in G Protein-Coupled Receptors

    Directory of Open Access Journals (Sweden)

    Rob van der Kant

    2014-05-01

    Full Text Available Agonist binding is related to a series of motions in G protein-coupled receptors (GPCRs that result in the separation of transmembrane helices III and VI at their cytosolic ends and subsequent G protein binding. A large number of smaller motions also seem to be associated with activation. Most helices in GPCRs are highly irregular and often contain kinks, with extensive literature already available about the role of prolines in kink formation and the precise function of these kinks. GPCR transmembrane helices also contain many α-bulges. In this article we aim to draw attention to the role of these α-bulges in ligand and G-protein binding, as well as their role in several aspects of the mobility associated with GPCR activation. This mobility includes regularization and translation of helix III in the extracellular direction, a rotation of the entire helix VI, an inward movement of the helices near the extracellular side, and a concerted motion of the cytosolic ends of the helices that makes their orientation appear more circular and that opens up space for the G protein to bind. In several cases, α-bulges either appear or disappear as part of the activation process.

  11. NPY, NPY receptors, and DPP IV activity are modulated by LPS, TNF-alpha and IFN-gamma in HUVEC.

    Science.gov (United States)

    Silva, Antonio P; Cavadas, Claudia; Baïsse-Agushi, Bénédicte; Spertini, Olivier; Brunner, Hans R; Grouzmann, Eric

    2003-11-15

    Since NPY increases endothelial cell (EC) stickiness for leukocytes, we studied the effects of LPS, TNF-alpha and IFN-gamma on its expression and action in HUVEC. Cytokines raised NPY and pro-NPY intracellular content and dipeptidyl peptidase IV (DPP IV) activity. Y1 and Y2 receptors were expressed in basal conditions, and LPS, TNF-alpha and IFN-gamma induced Y5 receptor expression with a concomitant extinction of Y2 receptor expression. NPY induced an intracellular calcium increase mainly mediated by Y2 and Y5 receptors in basal conditions. After stimulation with LPS, TNF-alpha and IFN-gamma, calcium increase was mainly caused by Y5 receptor. The modulation of the NPY system by LPS, TNF-alpha and IFN-gamma, and the NPY-induced calcium signaling suggest a role for NPY during the inflammatory response.

  12. Nuclear hormone receptor co-repressors: Structure and function

    Science.gov (United States)

    Watson, Peter J.; Fairall, Louise; Schwabe, John W.R.

    2012-01-01

    Co-repressor proteins, such as SMRT and NCoR, mediate the repressive activity of unliganded nuclear receptors and other transcription factors. They appear to act as intrinsically disordered “hub proteins” that integrate the activities of a range of transcription factors with a number of histone modifying enzymes. Although these co-repressor proteins are challenging targets for structural studies due to their largely unstructured character, a number of structures have recently been determined of co-repressor interaction regions in complex with their interacting partners. These have yielded considerable insight into the mechanism of assembly of these complexes, the structural basis for the specificity of the interactions and also open opportunities for targeting these interactions therapeutically. PMID:21925568

  13. Expression of two glycoprotein hormone receptors in larval, parasitic phase, and adult sea lampreys.

    Science.gov (United States)

    Hausken, Krist N; Marquis, Timothy J; Sower, Stacia A

    2017-11-21

    All jawed vertebrates have three canonical glycoprotein hormones (GpHs: luteinizing hormone, LH; follicle stimulating hormone, FSH; and thyroid stimulating hormone, TSH) with three corresponding GpH receptors (GpH-Rs: LH-R, FSH-R, and TSH-R). In contrast, we propose that the jawless vertebrate, the sea lamprey (Petromyzon marinus), only has two pituitary glycoprotein hormones, lamprey (l)GpH and l-thyrostimulin, and two functional glycoprotein receptors, lGpH-R I and II. It is not known at this time whether there is a specific receptor for lGpH and l-thyrostimulin, or if both GpHs can differentially activate the lGpH-Rs. In this report, we determined the RNA expression of lGpH-R I and II in the gonads and thyroids of larval, parasitic phase, and adult lampreys. A highly sensitive dual-label fluorescent in situ hybridization technique (RNAScope™) showed lGpH-R I expression in the ovaries of larval lamprey, and co-localization and co-expression of lGpH-R I and II in the ovaries of parasitic phase and adult lampreys. Both receptors were also highly co-localized and co-expressed in the endostyle of larval lamprey and thyroid follicles of parasitic and adult lampreys. In addition, we performed in vivo studies to determine the actions of lamprey gonadotropin releasing hormones (lGnRHs) on lGpH-R I and II expression by real time PCR, and determined plasma concentrations of estradiol and thyroxine. Administration of lGnRH-III significantly (p ≤ 0.01) increased lGpHR II expression in the thyroid follicles of adult female lampreys but did not cause a significant increase in RNA expression of lGpH-R I and II in ovaries. Concomitantly, there was a significant increase (p ≤ 0.01) of plasma estradiol without any significant changes of plasma thyroxine concentrations in response to treatment to lGnRH-I, -II, or -III. In summary, our results provide supporting evidence that the lamprey pituitary glycoprotein hormones may differentially activate the lamprey GpH-Rs in

  14. Expression of the growth hormone receptor gene in insulin producing cells

    DEFF Research Database (Denmark)

    Møldrup, Annette; Billestrup, N; Nielsen, Jens Høiriis

    1990-01-01

    Growth hormone (GH) plays a dual role in glucose homeostasis. On the one hand, it exerts an insulin antagonistic effect on the peripheral tissue, on the other hand, it stimulates insulin biosynthesis and beta-cell proliferation. The expression of GH-receptors on the rat insulinoma cell line RIN-5AH......-T2-clone B was studied. The binding characteristics with regard to specificity for the native 22 kDa hGH, and the 20 kDa variant were similar to that reported on rat adipocytes. Normal rat islet cells showed a similar affinity for hGH. The RIN cells express GH receptors similar to the cloned liver...... receptor. It is hypothesized that defects in the receptor expression on the beta-cells may contribute to the susceptibility to develop diabetes....

  15. Growth hormone-specific induction of the nuclear localization of porcine growth hormone receptor in porcine hepatocytes.

    Science.gov (United States)

    Lan, H N; Hong, P; Li, R N; Shan, A S; Zheng, X

    2017-10-01

    The phenomenon of nuclear translocation of growth hormone receptor (GHR) in human, rat, and fish has been reported. To date, this phenomenon has not been described in a domestic animal (such as pig). In addition, the molecular mechanisms of GHR nuclear translocation have not been thoroughly elucidated. To this end, porcine hepatocytes were isolated and used as a cell model. We observed that porcine growth hormone (pGH) can induce porcine GHR's nuclear localization in porcine hepatocytes. Subsequently, the dynamics of pGH-induced pGHR's nuclear localization were analyzed and demonstrated that pGHR's nuclear localization occurs in a time-dependent manner. Next, we explored the mechanism of pGHR nuclear localization using different pGHR ligands, and we demonstrated that pGHR's nuclear translocation is GH(s)-dependent. We also observed that pGHR translocates into cell nuclei in a pGH dimerization-dependent fashion, whereas further experiments indicated that IMPα/β is involved in the nuclear translocation of the pGH-pGHR dimer. The pGH-pGHR dimer may form a pGH-GHR-JAK2 multiple complex in cell nuclei, which would suggest that similar to its function in the cell membrane, the nuclear-localized pGH-pGHR dimer might still have the ability to signal. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Association of the thyroid stimulating hormone receptor gene (TSHR) with Graves' disease

    DEFF Research Database (Denmark)

    Brand, Oliver J; Barrett, Jeffrey C; Simmonds, Matthew J

    2009-01-01

    Graves' disease (GD) is a common autoimmune disease (AID) that shares many of its susceptibility loci with other AIDs. The thyroid stimulating hormone receptor (TSHR) represents the primary autoantigen in GD, in which autoantibodies bind to the receptor and mimic its ligand, thyroid stimulating...... hormone, causing the characteristic clinical phenotype. Although early studies investigating the TSHR and GD proved inconclusive, more recently we provided convincing evidence for association of the TSHR region with disease. In the current study, we investigated a combined panel of 98 SNPs, including 70.......32-1.78) and rs12101255 (chi(2) = 30.91, P = 1.95 x 10(-7), OR = 1.55, 95% CI = 1.33-1.81), both located in intron 1 of the TSHR. Association of the most associated SNP, rs179247, was replicated in 303 GD families (P = 7.8 x 10(-4)). In addition, we provide preliminary evidence that the disease...

  17. Receptors of Hypothalamic-Pituitary-Ovarian-Axis Hormone in Uterine Myomas

    Directory of Open Access Journals (Sweden)

    Danuta Plewka

    2014-01-01

    Full Text Available In this study the expression of GnRH, FSH, LH, ER-α, ER-β, and PR receptors was examined in uterine myomas of women in reproductive and perimenopausal age. In cases of GnRH and tropic hormones a membranous and cytoplasmic immunohistochemical reaction was detected, in cases of ER-α and PR the reaction was located in cell nucleus, and in the case of ER-β it manifested also a cytoplasmic location. In some of the examined cases the expression was detected in endometrium, myocytes, and endothelium of blood vessels, in uterine glands and myoma cells. In myometrium the level of GnRH and LH receptors increases with age, whereas the level of progesterone and both estrogen receptors decreases. In myomas of women in reproductive age, independently of their size, expression of GnRH, FSH, and LH receptors was more pronounced than in myometrium. In women of perimenopausal age, independently of myoma size, expression of LH and estrogen α receptors was higher while expression of GnRH receptors was lower than in myometrium. FSH receptor expression was not observed. Expression of estrogen receptor β was not affected by age of the woman or size of myoma. Analysis of obtained results indicates on existing in small myomas local feedback axis between GnRH-LH-progesterone.

  18. Involvement of Ghrelin-Growth Hormone Secretagogue Receptor System in Pathoclinical Profiles of Digestive System Cancer

    Institute of Scientific and Technical Information of China (English)

    Zhigang WANG; Weigang WANG; Wencai QIU; Youben FAN; Jun ZHAO; Yu WANG; Qi ZHENG

    2007-01-01

    Ghrelin receptor has been shown to be expressed along the human gastrointestinal tract.Recent studies showed that ghrelin and a synthetic ghrelin receptor agonist improved weight gain and lean body mass retention in a rat model of cancer cachexia by acting on ghrelin receptor, that is, growth hormone secretagogue receptor (GHS-R). This study aims to explore the expression and the distribution of ghrelin receptor in human gastrointestinal tract cancers and to investigate the possible involvement of the ghrelin-GHS-R system in human digestive cancers. Surgical human digestive cancer specimens were obtained from various portions of the gastrointestinal tract from different patients. The expression of ghrelin receptor in these tissues was detected by tissue microarray technique. Our results showed that ghrelin receptor was expressed in cancers throughout the gastrointestinal tract, mainly in the cytoplasm of mucosal layer cells.Its expression level possibly correlated with organ type, histological grade, tumor-nodes-metastases stage,and nutrition status (weight loss) of the patients. For the first time, we identified the distribution of ghrelin receptor in digestive system cancers. Our results implied that the ghrelin-GHS-R system might be involved in the pathoclinical profiles of digestive cancers.

  19. An Oral Selective Alpha-1A Adrenergic Receptor Agonist Prevents Doxorubicin Cardiotoxicity

    Directory of Open Access Journals (Sweden)

    Ju Youn Beak, PhD

    2017-02-01

    Full Text Available Summary: Alpha-1 adrenergic receptors (α1-ARs play adaptive and protective roles in the heart. Dabuzalgron is an oral selective α1A-AR agonist that was well tolerated in multiple clinical trials of treatment for urinary incontinence, but has never been used to treat heart disease in humans or animal models. In this study, the authors administered dabuzalgron to mice treated with doxorubicin (DOX, a widely used chemotherapeutic agent with dose-limiting cardiotoxicity that can lead to heart failure (HF. Dabuzalgron protected against DOX-induced cardiotoxicity, likely by preserving mitochondrial function. These results suggest that activating cardiac α1A-ARs with dabuzalgron, a well-tolerated oral agent, might represent a novel approach to treating HF. Key Words: alpha adrenergic receptors, anthracyclines, cardioprotection, catecholamines, heart failure

  20. Cloning and characterization of the adipokinetic hormone receptor from the cockroach Periplaneta americana

    DEFF Research Database (Denmark)

    Hansen, Karina K; Hauser, Frank; Cazzamali, Giuseppe

    2006-01-01

    Cockroaches have long been used as insect models to investigate the actions of biologically active neuropeptides. Here, we describe the cloning and functional expression in Chinese hamster ovary cells of an adipokinetic hormone (AKH) G protein-coupled receptor from the cockroach Periplaneta...... of both Pea-AKH-1 (EC50, 5 x 10(-9)M), and Pea-AKH-2 (EC50, 2 x 10(-9)M). Insects can be subdivided into two evolutionary lineages, holometabola (insects with a complete metamorphosis during development) and hemimetabola (incomplete metamorphosis). This paper describes the first AKH receptor from...

  1. A gate-latch-lock mechanism for hormone signalling by abscisic acid receptors

    KAUST Repository

    Melcher, Karsten

    2009-12-03

    Abscisic acid (ABA) is a ubiquitous hormone that regulates plant growth, development and responses to environmental stresses. Its action is mediated by the PYR/PYL/RCAR family of START proteins, but it remains unclear how these receptors bind ABA and, in turn, how hormone binding leads to inhibition of the downstream type 2C protein phosphatase (PP2C) effectors. Here we report crystal structures of apo and ABA-bound receptors as well as a ternary PYL2-ABA-PP2C complex. The apo receptors contain an open ligand-binding pocket flanked by a gate that closes in response to ABA by way of conformational changes in two highly conserved ?-loops that serve as a gate and latch. Moreover, ABA-induced closure of the gate creates a surface that enables the receptor to dock into and competitively inhibit the PP2C active site. A conserved tryptophan in the PP2C inserts directly between the gate and latch, which functions to further lock the receptor in a closed conformation. Together, our results identify a conserved gate-latch-lock mechanism underlying ABA signalling. © 2009 Macmillan Publishers Limited. All rights reserved.

  2. Incretin hormones and the expanding families of glucagon-like sequences and their receptors.

    Science.gov (United States)

    Irwin, D M; Prentice, K J

    2011-10-01

    Peptide hormones encoded by the proglucagon (Gcg) and glucose-dependent insulinotropic polypeptide (Gip) genes are evolutionarily related glucagon-like sequences and act through a subfamily of G-protein-coupled receptors. A better understanding of the evolutionary history of these hormones and receptors should yield insight into their biological functions. The availability of a large number of near-complete vertebrate genome sequences is a powerful resource to address questions concerning the evolution of sequences; here, we utilize these resources to examine the evolution of glucagon-like sequences and their receptors. These studies led to the discovery of novel genes for a glucagon receptor-like receptor (Grlr) and a glucagon-like sequence (exendin) in vertebrates. Both exendin and GRLR have ancient origins, early in vertebrate evolution, but have been lost on the ancestral lineage leading to extant mammals. We also show that exendin and GRLR are both expressed in the brain of the chicken and Xenopus tropicals, results that suggest that the products of these genes function in this tissue. The lack of exendin or Grlr genes in mammals suggests that other genes may have acquired the functions of exendin and Grlr during mammalian evolution. © 2011 Blackwell Publishing Ltd.

  3. Specific regulation of thermosensitive lipid droplet fusion by a nuclear hormone receptor pathway.

    Science.gov (United States)

    Li, Shiwei; Li, Qi; Kong, Yuanyuan; Wu, Shuang; Cui, Qingpo; Zhang, Mingming; Zhang, Shaobing O

    2017-08-15

    Nuclear receptors play important roles in regulating fat metabolism and energy production in humans. The regulatory functions and endogenous ligands of many nuclear receptors are still unidentified, however. Here, we report that CYP-37A1 (ortholog of human cytochrome P450 CYP4V2), EMB-8 (ortholog of human P450 oxidoreductase POR), and DAF-12 (homolog of human nuclear receptors VDR/LXR) constitute a hormone synthesis and nuclear receptor pathway in Caenorhabditis elegans This pathway specifically regulates the thermosensitive fusion of fat-storing lipid droplets. CYP-37A1, together with EMB-8, synthesizes a lipophilic hormone not identical to Δ7-dafachronic acid, which represses the fusion-promoting function of DAF-12. CYP-37A1 also negatively regulates thermotolerance and lifespan at high temperature in a DAF-12-dependent manner. Human CYP4V2 can substitute for CYP-37A1 in C. elegans This finding suggests the existence of a conserved CYP4V2-POR-nuclear receptor pathway that functions in converting multilocular lipid droplets to unilocular ones in human cells; misregulation of this pathway may lead to pathogenic fat storage.

  4. [Rare abnormalities of parathyroid gland function and parathyroid hormone receptor action].

    Science.gov (United States)

    Krysiak, Robert; Bartecka, Anna; Okopień, Bogusław

    2014-01-01

    The parathyroid glands, located near or within the posterior surface of the thyroid gland and secreting parathyroid hormone, are essential organs for the regulation of calcium and phosphate metabolism. As they are necessary to sustain life and maintain homeostasis, undetected or misdiagnosed parathyroid disorders may pose a significant threat to health outcomes, as their presence may increase morbidity and mortality in affected individuals. The clinical picture of some disorders associated with abnormal parathyroid hormone secretion and receptor action is sometimes complicated by coexisting abnormalities, and in these cases establishing the correct diagnosis is challenging. The remarkable progress of recent years in the area of hormonal assessment, imaging procedures and molecular biology, has resulted in a great improvement in the identification, differentiation and treatment of various parathyroid disorders and has made it possible to identify several new clinical entities. In this paper, we discuss the present state-of-art on the etiopathogenesis, clinical manifestations, diagnosis and treatment of chosen rare abnormalities of parathyroid gland function and parathyroid hormone receptor action.

  5. Association between contralateral prophylactic mastectomy and breast cancer outcomes by hormone receptor status.

    Science.gov (United States)

    Brewster, Abenaa M; Bedrosian, Isabelle; Parker, Patricia A; Dong, Wenli; Peterson, Susan K; Cantor, Scott B; Crosby, Melissa; Shen, Yu

    2012-11-15

    The effect of contralateral prophylactic mastectomy (CPM) on the survival of patients with early-stage breast cancer remains controversial. The objective of this study was to evaluate the benefits of CPM using a propensity scoring approach that reduces selection bias from the nonrandom assignment of patients in observational studies. A total of 3889 female patients with stage I to III breast cancer were identified who were treated at The University of Texas MD Anderson Cancer Center from 1997 to 2009. We assessed the association between CPM and disease-free (DFS) and overall survival (OS), by using Cox proportional hazards models to estimate hazard ratios (HRs), and by matching patients in the CPM and no-CPM groups using propensity scores (n = 497 pairs). With a median follow-up time of 4.5 years, CPM was associated with improved DFS (HR, 0.75; 95% confidence interval [CI], 0.59-0.97) and OS (HR, 0.74; 95% CI, 0.56-0.99), adjusted for prognostic factors. The improved DFS was seen predominantly among hormone receptor-negative (HR, 0.60; 95% CI, 0.38-0.95) compared with hormone receptor-positive patients (HR, 0.80; 95% CI, 0.58-1.10). For the matched patient cohort, stratified survival analysis also showed an improvement in DFS with CPM (HR, 0.48; 95% CI, 0.22-1.01) in hormone receptor-negative patients that was nearly statistically significant. CPM was associated with improved DFS for some patients with hormone receptor-negative breast cancer, after reducing selection bias. Identifying subsets of patients most likely to benefit from CPM may have important implications for a more personalized approach to treatment decisions about CPM. Copyright © 2012 American Cancer Society.

  6. Prostate-specific antigen and hormone receptor expression in male and female breast carcinoma

    Directory of Open Access Journals (Sweden)

    Cohen Cynthia

    2010-09-01

    Full Text Available Abstract Background Prostate carcinoma is among the most common solid tumors to secondarily involve the male breast. Prostate specific antigen (PSA and prostate-specific acid phosphatase (PSAP are expressed in benign and malignant prostatic tissue, and immunohistochemical staining for these markers is often used to confirm the prostatic origin of metastatic carcinoma. PSA expression has been reported in male and female breast carcinoma and in gynecomastia, raising concerns about the utility of PSA for differentiating prostate carcinoma metastasis to the male breast from primary breast carcinoma. This study examined the frequency of PSA, PSAP, and hormone receptor expression in male breast carcinoma (MBC, female breast carcinoma (FBC, and gynecomastia. Methods Immunohistochemical staining for PSA, PSAP, AR, ER, and PR was performed on tissue microarrays representing six cases of gynecomastia, thirty MBC, and fifty-six FBC. Results PSA was positive in two of fifty-six FBC (3.7%, focally positive in one of thirty MBC (3.3%, and negative in the five examined cases of gynecomastia. PSAP expression was absent in MBC, FBC, and gynecomastia. Hormone receptor expression was similar in males and females (AR 74.1% in MBC vs. 67.9% in FBC, p = 0.62; ER 85.2% vs. 68.5%, p = 0.18; and PR 51.9% vs. 48.2%, p = 0.82. Conclusions PSA and PSAP are useful markers to distinguish primary breast carcinoma from prostate carcinoma metastatic to the male breast. Although PSA expression appeared to correlate with hormone receptor expression, the incidence of PSA expression in our population was too low to draw significant conclusions about an association between PSA expression and hormone receptor status in breast lesions.

  7. UV filters induce transcriptional changes of different hormonal receptors in Chironomus riparius embryos and larvae.

    Science.gov (United States)

    Ozáez, Irene; Aquilino, Mónica; Morcillo, Gloria; Martínez-Guitarte, José-Luis

    2016-07-01

    Organic ultraviolet (UV) filters are emerging contaminants that are ubiquitous in fresh and marine aquatic systems due to their extensive use in cosmetics, plastics, paints, textiles, and many other industrial products. The estrogenic effects of organic UV filters have been long demonstrated in vertebrates, and other hormonal activities may be altered, according to more recent reports. The impact of UV filters on the endocrine system of invertebrates is largely unknown. We have previously reported that some UV filters may affect ecdysone-related genes in the aquatic insect Chironomus riparius, an ecotoxicologically important model organism. To further analyze other possible effects on endocrine pathways, we first characterized four pivotal genes related with hormonal pathways in insects; thereafter, these genes were assessed for alterations in transcriptional activity after exposure to 4-methylbenzylidene camphor (4MBC) or benzophenone-3 (BP-3), two extensively used sunscreens. We found that both chemicals disturbed the expression of all four genes analyzed: hormonal receptor 38 (HR38), methoprene-tolerant (Met), membrane-associate progesterone receptor (MAPR) and insulin-like receptor (INSR), measured by changes in mRNA levels by real-time PCR. An upregulatory effect at the genomic level was detected in different developmental stages. Interestingly, embryos appeared to be more sensitive to the action of the UV filters than larvae. Our results suggest that the risk of disruption through different endocrine routes is not negligible, considering the significant effects of UV filters on key hormonal receptor and regulatory genes. Further effort is needed to develop environmental risk assessment studies on these pollutants, particularly for aquatic invertebrate model organisms. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Neurosteroid regulation of GABA(A) receptors: Focus on the alpha4 and delta subunits.

    Science.gov (United States)

    Smith, Sheryl S; Shen, Hui; Gong, Qi Hua; Zhou, Xiangping

    2007-10-01

    Neurosteroids, such as the progesterone metabolite 3alpha-OH-5alpha[beta]-pregnan-20-one (THP or [allo]pregnanolone), function as potent positive modulators of the GABA(A) receptor (GABAR) when acutely administered. However, fluctuations in the circulating levels of this steroid at puberty, across endogenous ovarian cycles, during pregnancy or following chronic stress produce periods of prolonged exposure and withdrawal, where changes in GABAR subunit composition may occur as compensatory responses to sustained levels of inhibition. A number of laboratories have demonstrated that both chronic administration of THP as well as its withdrawal transiently increase expression of the alpha4 subunit of the GABAR in several areas of the central nervous system (CNS) as well as in in vitro neuronal systems. Receptors containing this subunit are insensitive to benzodiazepine (BDZ) modulation and display faster deactivation kinetics, which studies suggest underlie hyperexcitability states. Similar increases in alpha4 expression are triggered by withdrawal from other GABA-modulatory compounds, such as ethanol and BDZ, suggesting a common mechanism. Other studies have reported puberty or estrous cycle-associated increases in delta-GABAR, the most sensitive target of these steroids which underlies a tonic inhibitory current. In the studies reported here, the effect of steroids on inhibition, which influence anxiety state and seizure susceptibility, depend not only on the subunit composition of the receptor but also on the direction of Cl(-) current generated by these target receptors. The effect of neurosteroids on GABAR function thus results in behavioral outcomes relevant for pubertal mood swings, premenstrual dysphoric disorder and catamenial epilepsy, which are due to fluctuations in endogenous steroids.

  9. Estrogen Receptor Alpha Distribution and Expression in the Social Neural Network of Monogamous and Polygynous Peromyscus

    OpenAIRE

    Cushing, Bruce S.

    2016-01-01

    In microtine and dwarf hamsters low levels of estrogen receptor alpha (ERα) in the bed nucleus of the stria terminalis (BST) and medial amygdala (MeA) play a critical role in the expression of social monogamy in males, which is characterized by high levels of affiliation and low levels of aggression. In contrast, monogamous Peromyscus males display high levels of aggression and affiliative behavior with high levels of testosterone and aromatase activity. Suggesting the hypothesis that in Pero...

  10. Subtype selectivity of [alpha]+[beta]- site ligands of GABAA receptors: identification of the first highly specific positive modulators at [alpha]6[beta]2/3[gamma]2 receptors

    National Research Council Canada - National Science Library

    Varagic, Zdravko; Ramerstorfer, Joachim; Huang, Shengming; Rallapalli, Sundari; Sarto-Jackson, Isabella; Cook, James; Sieghart, Werner; Ernst, Margot

    2013-01-01

    .... Key Results Pyrazoloquinolinones and pyrazolopyridinones represent the first prototypes of drugs exerting benzodiazepine-like modulatory effects via the [alpha]+[beta]- interface of GABA.sub.A receptors...

  11. Estrogen prevents norepinephrine alpha-2a receptor reversal of stress-induced working memory impairment.

    Science.gov (United States)

    Shansky, Rebecca M; Bender, Genevieve; Arnsten, A F T

    2009-09-01

    Understanding effects of estrogen on the medial prefrontal cortex (PFC) may help to elucidate the increased prevalence of depression and post-traumatic stress disorder in women of ovarian cycling age. Estrogen replacement in ovariectomized (OVX) young rats amplifies the detrimental effects of stress on working memory (a PFC-mediated task), but the mechanisms by which this occurs have yet to be identified. In male rats, stimulation of norepinephrine alpha-2 adrenoceptors protects working memory from stress-induced impairments. However, this effect has not been studied in females, and has not been examined for sensitivity to estrogen. The current study asked whether OVX females with estrogen replacement (OVX+Est) and without replacement (OVX+Veh) responded differently to stimulation of alpha-2 adrenoceptors after administration of the benzodiazepine inverse agonist FG7142, a pharmacological stressor. The alpha-2 agonist, guanfacine, protected working memory from the impairing effects of FG7142 in OVX+Veh, but not in OVX+Est rats. Western Blot analysis for alpha-2 receptors was performed on PFC tissue from each group, but no changes in expression were found, indicating that the behavioral effects observed were likely not due to changes in receptor expression. These findings point to possible mechanisms by which estrogen may enhance the stress response, and hold implications for the gender discrepancy in the prevalence of stress-related mental illness.

  12. [Laryngeal effect of experimental postnatal hypothyroidism: do thyroid hormone receptors change?].

    Science.gov (United States)

    Eryılmaz, Aylin; Günel, Ceren; Eliyatkın, Nuket; Cesur, Gökhan; Türe, Mevlüt; Başal, Yeşim

    2016-01-01

    In this study, we aimed to investigate the laryngeal histopathological alterations and thyroid hormone receptors in rats with experimentally-induced postnatal hypothyroidism. In this prospective, randomized study, pregnant Wistar albino rats were followed and newborn 20 Wistar albino rat pups were included in the study. The pups were randomly divided into two groups: In group 1 (methimazole (MMI)-induced hypothyroidism group), the mothers and pups were given MMI added water up to 90th day, as the pups were fed with breast milk for 19 to 22 days. In group 2 (control group), the mothers and pups were fed with MMI-free water up to 90th days. When the pups were 90 days of age, they were decapitated and their larynx was removed. Their larynx was evaluated for edema, inflammation, goblet cells, and thyroid hormone receptors (TR-α, TR-β). Nine larynx samples for group 1 and eight for group 2 were studied. There was a significant difference in inflammation between the groups with slightly lower in the hypothyroidism group (p=0.009). The TR-α, TR-β, and edema were significantly higher in the hypothyroidism group (p=0.002, p=0.029, p=0.029). There was no significant difference in the Goblet cells between the groups (p=0.637). Histopathologically increased laryngeal edema and increased thyroid hormone receptors were found, shedding light on the mechanism of voice changes in hypothyroidism.

  13. Association between hormone receptors and HER-2/neu is age-related.

    Science.gov (United States)

    Wang, Bo; Wang, Xiaoling; Zou, Yinying

    2015-01-01

    To investigate the association between hormone receptors and HER-2/neu in different age groups of women with breast cancers. A total of 1036 women with breast cancers were recruited. All the patients were divided into nine groups. The expression of hormone receptors and HER-2/neu was studied by IHC, while FISH test was used to determine HER-2/neu status in cases scored IHC 2+. The association between hormone receptors and HER-2/neu in different age groups was evaluated using the χ(2) test. Multivariate analysis was used to find out the independent factors predicting HER-2/neu amplification. Significant findings: The expression of ER and PR was inversely correlated with HER-2/neu status in women aged >40 years. By multivariate analysis, as far as the overall groups were concerned, PR, lymph node status and tumor grade were independently associated with HER-2/neu; Considering the younger age group (≤ 40), the only predictor for HER-2/neu was the tumor grade; Considering the older age group (>40), tumor grade, PR status, tumor size and lymph node status were associated with HER-2/neu overexpression. Our data suggest that the association between ER, PR and HER-2/neu is age-related. The negative relationship is only applied for women aged >40 years.

  14. Molecular determinants of desensitization and assembly of the chimeric GABA(A) receptor subunits (alpha1/gamma2) and (gamma2/alpha1) in combinations with beta2 and gamma2

    DEFF Research Database (Denmark)

    Elster, L; Kristiansen, U; Pickering, D S

    2001-01-01

    Two gamma-aminobutyric acid(A) (GABA(A)) receptor chimeras were designed in order to elucidate the structural requirements for GABA(A) receptor desensitization and assembly. The (alpha1/gamma2) and (gamma2/alpha1) chimeric subunits representing the extracellular N-terminal domain of alpha1 or gamma...... for assembly. However, the (alpha1/gamma2) chimeric subunit had characteristics different from the alpha1 subunit, since the (alpha1/gamma2) chimera gave rise to no desensitization after GABA stimulation in whole-cell patch-clamp recordings, which was independent of whether the chimera was expressed......, as opposed to the staining of the (gamma2/alpha1)-containing receptors, which was only slightly higher than background. To explain this, the (alpha1/gamma2) and (gamma2/alpha1) chimeras may act like alpha1 and gamma2 subunits, respectively, indicating that the extracellular N-terminal segment is important...

  15. Retinoic acid receptor alpha amplifications and retinoic acid sensitivity in breast cancers.

    Science.gov (United States)

    Alsafadi, Samar; Even, Caroline; Falet, Coralie; Goubar, Aicha; Commo, Frédéric; Scott, Véronique; Quidville, Virginie; Albiges, Laurence; Dieci, Maria-Vittoria; Guegan, Justine; Lazar, Vladimir; Ahomadegbe, Jean-Charles; Delaloge, Suzette; André, Fabrice

    2013-10-01

    Molecular segmentation of breast cancer allows identification of small groups of patients who present high sensitivity to targeted agents. A patient, with chemo- and trastuzumab-resistant HER2-overexpressing breast cancer, who presented concomitant acute promyelocytic leukemia, showed a response in her breast lesions to retinoic acid, arsenic, and aracytin. We therefore investigated whether RARA gene amplification could be associated with sensitivity to retinoic acid derivatives in breast cancers. Array comparative genomic hybridization and gene expression arrays were used to characterize RARA amplifications and expression in 103 breast cancer samples. In vitro activity of ATRA was characterized in T47D, SKBR3, and BT474 cell lines. Retinoic acid receptor alpha was gained or amplified in 27% of HER2-positive and 13% of HER2-negative breast cancer samples. Retinoic acid receptor alpha can be coamplified with HER2. Retinoic acid receptor alpha copy number changes could be correlated with messenger RNA expression. All-trans-retinoic acid reduced cell viability of RARA-amplified, but not RARA-normal, cell lines through apoptosis. Gene expression arrays showed that ATRA-induced apoptosis in RARA-amplified cell lines was related to an increase in CASP1 and IRF1. The results of this study suggest that breast cancers exhibiting RARA amplifications could be sensitive to retinoic acid. A phase II trial will evaluate this hypothesis in the clinical setting. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Height, age at menarche and risk of hormone receptor-positive and -negative breast cancer: A cohort study

    NARCIS (Netherlands)

    Ritte, R.; Lukanova, A.; Tjonneland, A.; Olsen, A.; Overvad, K.; Mesrine, S.; Fagherazzi, G.; Dossus, L.; Teucher, B.; Duijnhoven, van F.J.B.

    2013-01-01

    Associations of breast cancer overall with indicators of exposures during puberty are reasonably well characterized; however, uncertainty remains regarding the associations of height, leg length, sitting height and menarcheal age with hormone receptor-defined malignancies. Within the European

  17. Steroid Hormone Receptors as Potential Mediators of the Clinical Effects of Dutasteride: A Prospective, Randomized, Double-Blind Study

    National Research Council Canada - National Science Library

    Alonso, João C. C; Reis, Leonardo O; Garcia, Patrick V; Ferreira, Ubirajara; Matheus, Wagner E; Simões, Fabiano A; Rejowski, Ronald F; Alonso-Vale, Maria Isabel C; Fávaro, Wagner J

    2017-01-01

    This study characterizes the clinical and morphofunctional effects of a 5α-reductase inhibitor on steroid hormone receptors in normal human prostate tissue, as potential mediators of the clinical effects of dutasteride...

  18. Receptors as microprocessors: pharmacological nuance on metabotropic glutamate receptors 1alpha.

    Science.gov (United States)

    Kenakin, Terry

    2006-07-03

    G protein-coupled receptors have revealed themselves to be complex information-processing units that may be exploited for subtle therapeutic signaling effects. Thus, ligands may not only turn receptors on and off, but may also select from their repertoire of signaling effects to further refine drug response.

  19. Risk of Breast Cancer in Relation to Combined Effects of Hormone Therapy, Body Mass Index, and Alcohol Use, by Hormone-receptor Status

    DEFF Research Database (Denmark)

    Hvidtfeldt, Ulla Arthur; Tjonneland, Anne; Keiding, Niels

    2015-01-01

    -risk" users is important for therapeutic reasons. We investigated interactions between hormone therapy use and alcohol-use/high BMI status in relation to invasive breast cancer risk, both overall and according to estrogen receptor (ER) status. METHODS: Two Danish prospective cohorts were pooled, including 30......BACKGROUND: Alcohol consumption, increased body mass index (BMI), and hormone therapy are risk factors for postmenopausal breast cancer, but their combined effects are not well understood. Because hormone therapy is effective for the relief of menopausal symptoms, the identification of "high......,938 person-years of follow-up, 1579 women developed invasive breast cancer. Among nonusers of hormone therapy, the risk of breast cancer was slightly increased with overweight/obesity and increasing alcohol consumption. Compared with normal-weight nonusers, the risk of breast cancer was higher in hormone...

  20. Binding sites for. alpha. -bungarotoxin and the noncompetitive inhibitor phencyclidine on a synthetic peptide comprising residues 172-227 of the. alpha. -subunit of the nicotinic acetylcholine receptor

    Energy Technology Data Exchange (ETDEWEB)

    Donnelly-Roberts, D.L.; Lentz, T.L. (Yale Univ., New Haven, CT (United States))

    1991-07-30

    The binding of the competitive antagonist {alpha}-bungarotoxin ({alpha}-Btx) and the noncompetitive inhibitor phencyclidine (PCP) to a synthetic peptide comprising residues 172-227 of the {alpha}-subunit of the Torpedo acetylcholine receptor has been characterized. {sup 125}I-{alpha}-Btx bound to the 172-227 peptide in a solid-phase assay and was competed by {alpha}-Btx d-tubocurarine and NaCl. In the presence of 0.02% sodium dodecyl sulfate, {sup 125}I-{alpha}-Btx bound to the 56-residue peptide with a K{sub D} of 3.5 nM, as determined by equilibrium saturation binding studies. Because {alpha}Btx binds to a peptide comprising residues 173-204 with the same affinity and does not bind to a peptide comprising residues 205-227, the competitive antagonist and hence agonist binding site lies between residues 173 and 204. After photoaffinity labeling, ({sup 3}H)PCP was bound to the 172-227 peptide. ({sup 3}H)PCP binding was inhibited by chlorpromazine, tetracaine, and dibucaine. It is concluded that a high-affinity binding site for PCP is located between residues 205 and 227, which includes the first 18 residues of transmembrane segment M1, and that a low-affinity site is located in the competitive antagonist binding site between residues 173 and 204. These results show that a synthetic peptide comprising residues 172-227 of the {alpha} subunit contains three binding sites, one for {alpha}-Btx and two for PCP. Previous studies on the intact receptor indicate high-affinity PCP binding occurs in the receptor channel.

  1. AP-2{alpha} suppresses skeletal myoblast proliferation and represses fibroblast growth factor receptor 1 promoter activity

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Darrion L. [Department of Cell Biology and Anatomy, Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064 (United States); DiMario, Joseph X., E-mail: joseph.dimario@rosalindfranklin.edu [Department of Cell Biology and Anatomy, Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064 (United States)

    2010-01-15

    Skeletal muscle development is partly characterized by myoblast proliferation and subsequent differentiation into postmitotic muscle fibers. Developmental regulation of expression of the fibroblast growth factor receptor 1 (FGFR1) gene is required for normal myoblast proliferation and muscle formation. As a result, FGFR1 promoter activity is controlled by multiple transcriptional regulatory proteins during both proliferation and differentiation of myogenic cells. The transcription factor AP-2{alpha} is present in nuclei of skeletal muscle cells and suppresses myoblast proliferation in vitro. Since FGFR1 gene expression is tightly linked to myoblast proliferation versus differentiation, the FGFR1 promoter was examined for candidate AP-2{alpha} binding sites. Mutagenesis studies indicated that a candidate binding site located at - 1035 bp functioned as a repressor cis-regulatory element. Furthermore, mutation of this site alleviated AP-2{alpha}-mediated repression of FGFR1 promoter activity. Chromatin immunoprecipitation studies demonstrated that AP-2{alpha} interacted with the FGFR1 promoter in both proliferating myoblasts and differentiated myotubes. In total, these results indicate that AP-2{alpha} is a transcriptional repressor of FGFR1 gene expression during skeletal myogenesis.

  2. Gonadotropin-Releasing Hormone (GnRH) Receptor Structure and GnRH Binding.

    Science.gov (United States)

    Flanagan, Colleen A; Manilall, Ashmeetha

    2017-01-01

    Gonadotropin-releasing hormone (GnRH) regulates reproduction. The human GnRH receptor lacks a cytoplasmic carboxy-terminal tail but has amino acid sequence motifs characteristic of rhodopsin-like, class A, G protein-coupled receptors (GPCRs). This review will consider how recent descriptions of X-ray crystallographic structures of GPCRs in inactive and active conformations may contribute to understanding GnRH receptor structure, mechanism of activation and ligand binding. The structures confirmed that ligands bind to variable extracellular surfaces, whereas the seven membrane-spanning α-helices convey the activation signal to the cytoplasmic receptor surface, which binds and activates heterotrimeric G proteins. Forty non-covalent interactions that bridge topologically equivalent residues in different transmembrane (TM) helices are conserved in class A GPCR structures, regardless of activation state. Conformation-independent interhelical contacts account for a conserved receptor protein structure and their importance in the GnRH receptor structure is supported by decreased expression of receptors with mutations of residues in the network. Many of the GnRH receptor mutations associated with congenital hypogonadotropic hypogonadism, including the Glu2.53(90) Lys mutation, involve amino acids that constitute the conserved network. Half of the ~250 intramolecular interactions in GPCRs differ between inactive and active structures. Conformation-specific interhelical contacts depend on amino acids changing partners during activation. Conserved inactive conformation-specific contacts prevent receptor activation by stabilizing proximity of TM helices 3 and 6 and a closed G protein-binding site. Mutations of GnRH receptor residues involved in these interactions, such as Arg3.50(139) of the DRY/S motif or Tyr7.53(323) of the N/DPxxY motif, increase or decrease receptor expression and efficiency of receptor coupling to G protein signaling, consistent with the native residues

  3. Interaction of 14-3-3 proteins with the Estrogen Receptor Alpha F domain provides a drug target interface

    NARCIS (Netherlands)

    De Vries-van Leeuwen, Ingrid J; da Costa Pereira, Daniel; Flach, Koen D; Piersma, Sander R; Haase, Christian; Bier, David; Yalcin, Zeliha; Michalides, Rob; Feenstra, K Anton; Jiménez, Connie R; de Greef, Tom F A; Brunsveld, Luc; Ottmann, Christian; Zwart, Wilbert; de Boer, Albertus H

    2013-01-01

    Estrogen receptor alpha (ERα) is involved in numerous physiological and pathological processes, including breast cancer. Breast cancer therapy is therefore currently directed at inhibiting the transcriptional potency of ERα, either by blocking estrogen production through aromatase inhibitors or

  4. Prolactin receptor, growth hormone receptor, and putative somatolactin receptor in Mozambique tilapia: tissue specific expression and differential regulation by salinity and fasting.

    Science.gov (United States)

    Pierce, A L; Fox, B K; Davis, L K; Visitacion, N; Kitahashi, T; Hirano, T; Grau, E G

    2007-01-01

    In fish, pituitary growth hormone family peptide hormones (growth hormone, GH; prolactin, PRL; somatolactin, SL) regulate essential physiological functions including osmoregulation, growth, and metabolism. Teleost GH family hormones have both differential and overlapping effects, which are mediated by plasma membrane receptors. A PRL receptor (PRLR) and two putative GH receptors (GHR1 and GHR2) have been identified in several teleost species. Recent phylogenetic analyses and binding studies suggest that GHR1 is a receptor for SL. However, no studies have compared the tissue distribution and physiological regulation of all three receptors. We sequenced GHR2 from the liver of the Mozambique tilapia (Oreochromis mossambicus), developed quantitative real-time PCR assays for the three receptors, and assessed their tissue distribution and regulation by salinity and fasting. PRLR was highly expressed in the gill, kidney, and intestine, consistent with the osmoregulatory functions of PRL. PRLR expression was very low in the liver. GHR2 was most highly expressed in the muscle, followed by heart, testis, and liver, consistent with this being a GH receptor with functions in growth and metabolism. GHR1 was most highly expressed in fat, liver, and muscle, suggesting a metabolic function. GHR1 expression was also high in skin, consistent with a function of SL in chromatophore regulation. These findings support the hypothesis that GHR1 is a receptor for SL. In a comparison of freshwater (FW)- and seawater (SW)-adapted tilapia, plasma PRL was strongly elevated in FW, whereas plasma GH was slightly elevated in SW. PRLR expression was reduced in the gill in SW, consistent with PRL's function in freshwater adaptation. GHR2 was elevated in the kidney in FW, and correlated negatively with plasma GH, whereas GHR1 was elevated in the gill in SW. Plasma IGF-I, but not GH, was reduced by 4 weeks of fasting. Transcript levels of GHR1 and GHR2 were elevated by fasting in the muscle. However

  5. ACTH, alpha-MSH, and control of cortisol release: cloning, sequencing, and functional expression of the melanocortin-2 and melanocortin-5 receptor in Cyprinus carpio

    NARCIS (Netherlands)

    Metz, J.R.; Geven, E.J.W.; Burg, E.H. van den; Flik, G.

    2005-01-01

    Cortisol release from fish head kidney during the acute phase of the stress response is controlled by the adrenocorticotropic hormone (ACTH) from the pituitary pars distalis (PD). Alpha-melanocyte-stimulating hormone (alpha-MSH) and beta-endorphin, from the pars intermedia (PI), have been implicated

  6. Dioxin increases the interaction between aryl hydrocarbon receptor and estrogen receptor alpha at human promoters

    DEFF Research Database (Denmark)

    Ahmed, Shaaima; Valen, Eivind; Sandelin, Albin Gustav

    2009-01-01

    Recent studies have shown that activated aryl hydrocarbon receptor (AHR) induced the recruitment of estrogen receptor- (ER ) to AHR-regulated genes and that AHR is recruited to ER -regulated genes. However, these findings were limited to a small number of well-characterized AHR- or ER -responsive...... regions bound by both AHR and ER . Conventional and sequential ChIPs confirmed the recruitment of AHR and ER to many of the identified regions. Transcription factor binding site analysis revealed an overrepresentation of aryl hydrocarbon receptor response elements in regions bound by both AHR and ER...

  7. Blockade of alcohol's amnestic activity in humans by an alpha5 subtype benzodiazepine receptor inverse agonist.

    Science.gov (United States)

    Nutt, David J; Besson, Marie; Wilson, Susan J; Dawson, Gerard R; Lingford-Hughes, Anne R

    2007-12-01

    Alcohol produces many subjective and objective effects in man including pleasure, sedation, anxiolysis, plus impaired eye movements and memory. In human volunteers we have used a newly available GABA-A/benzodiazepine receptor inverse agonist that is selective for the alpha5 subtype (a5IA) to evaluate the role of this subtype in mediating these effects of alcohol on the brain. After pre-treatment with a5IA, we found almost complete blockade of the marked impairment caused by alcohol (mean breath concentration 150mg/100ml) of word list learning and partial but non-significant reversal of subjective sedation without effects on other measures such as intoxication, liking, and slowing of eye movements. This action was not due to alterations in alcohol kinetics and so provides the first proof of concept that selectively decreasing GABA-A receptor function at a specific receptor subtype can offset some actions of alcohol in humans. It also supports growing evidence for a key role of the alpha5 subtype in memory. Inverse agonists at other GABA-A receptor subtypes may prove able to reverse other actions of alcohol, and so offer a new approach to understanding the actions of alcohol in the human brain and in the treatment of alcohol related disorders in humans.

  8. Resistance to thyroid hormone due to a novel thyroid hormone receptor mutant in a patient with hypothyroidism secondary to lingual thyroid and functional characterization of the mutant receptor.

    Science.gov (United States)

    Nakajima, Yasuyo; Yamada, Masanobu; Horiguchi, Kazuhiko; Satoh, Tetsurou; Hashimoto, Koshi; Tokuhiro, Etsuro; Onigata, Kazuhiko; Mori, Masatomo

    2010-08-01

    We describe a rare case of congenital hypothyroidism and an extremely high serum thyrotropin (TSH) level caused by a combination of resistance to thyroid hormone (RTH) and a lingual thyroid. As the RTH mutant, R316C, was new, the optimum dose of levothyroxine was unclear. To aid in assessment of the therapy, we characterized the mutant R316C thyroid hormone receptor (TR) and compared it with a common mutant, R316H, using in vitro studies. The patient was a newborn female having severe hypothyroidism with a free thyroxine level of 0.36 ng/dL and a serum TSH level of 177 microU/mL. A scintiscan showed ectopic lingual thyroid tissue without a normal thyroid gland. Supplementation with levothyroxine at a dose of >350 microg/day did not normalize the serum TSH level; however, the patient showed normal growth and intelligence at 14 years of age. Consistent with the results of a computer analysis, the binding of R316C to triiodothyronine (T3) was significantly decreased to 38% that of the wild type. Electrophoretic mobility shift assay demonstrated that like R316H, R316C did not form a homodimer, but formed a heterodimer with RXR. However, a glutathione-S-transferase pull-down assay showed reduced binding of R316C with NCoR in the absence of T3 and impaired release in the presence of T3. In addition, transient transfection experiments demonstrated that unlike R316H, R316C had severe impairment of transcriptional activity on genes both positively and negatively regulated by thyroid hormone. It also had a clear dominant negative effect on genes negatively, but not positively, regulated by thyroid hormone, including the TSH-releasing hormone and TSHbeta genes. This is the first reported case of a R316C TR mutation. The characteristics of the R316C mutant differed from those of the R316H mutant. Our findings suggest that R316C causes reduced association with and impaired release of NCoR, resulting in RTH predominantly at the pituitary level, and that slightly elevated serum

  9. Family history and breast cancer hormone receptor status in a Spanish cohort.

    Directory of Open Access Journals (Sweden)

    Xuejuan Jiang

    Full Text Available BACKGROUND: Breast cancer is a heterogenous disease that impacts racial/ethnic groups differently. Differences in genetic composition, lifestyles, reproductive factors, or environmental exposures may contribute to the differential presentation of breast cancer among Hispanic women. MATERIALS AND METHODS: A population-based study was conducted in the city of Santiago de Compostela, Spain. A total of 645 women diagnosed with operable invasive breast cancer between 1992 and 2005 participated in the study. Data on demographics, breast cancer risk factors, and clinico-pathological characteristics of the tumors were collected. Hormone receptor negative tumors were compared with hormone receptor postive tumors on their clinico-pathological characteristics as well as risk factor profiles. RESULTS: Among the 645 breast cancer patients, 78% were estrogen receptor-positive (ER+ or progesterone receptor-positive (PR+, and 22% were ER-&PR-. Women with a family history of breast cancer were more likely to have ER-&PR- tumors than women without a family history (Odds ratio, 1.43; 95% confidence interval, 0.91-2.26. This association was limited to cancers diagnosed before age 50 (Odds ratio, 2.79; 95% confidence interval, 1.34-5.81. CONCLUSIONS: An increased proportion of ER-&PR- breast cancer was observed among younger Spanish women with a family history of the disease.

  10. The Nuclear Hormone Receptor PPARγ as a Therapeutic Target in Major Diseases

    Directory of Open Access Journals (Sweden)

    Martina Victoria Schmidt

    2010-01-01

    Full Text Available The peroxisome proliferator-activated receptor γ (PPARγ belongs to the nuclear hormone receptor superfamily and regulates gene expression upon heterodimerization with the retinoid X receptor by ligating to peroxisome proliferator response elements (PPREs in the promoter region of target genes. Originally, PPARγ was identified as being essential for glucose metabolism. Thus, synthetic PPARγ agonists, the thiazolidinediones (TZDs, are used in type 2 diabetes therapy as insulin sensitizers. More recent evidence implied an important role for the nuclear hormone receptor PPARγ in controlling various diseases based on its anti-inflammatory, cell cycle arresting, and proapoptotic properties. In this regard, expression of PPARγ is not restricted to adipocytes, but is also found in immune cells, such as B and T lymphocytes, monocytes, macrophages, dendritic cells, and granulocytes. The expression of PPARγ in lymphoid organs and its modulation of macrophage inflammatory responses, lymphocyte proliferation, cytokine production, and apoptosis underscore its immune regulating functions. Moreover, PPARγ expression is found in tumor cells, where its activation facilitates antitumorigenic actions. This review provides an overview about the role of PPARγ as a possible therapeutic target approaching major, severe diseases, such as sepsis, cancer, and atherosclerosis.

  11. Social information changes stress hormone receptor expression in the songbird brain.

    Science.gov (United States)

    Cornelius, Jamie M; Perreau, Gillian; Bishop, Valerie R; Krause, Jesse S; Smith, Rachael; Hahn, Thomas P; Meddle, Simone L

    2018-01-01

    Social information is used by many vertebrate taxa to inform decision-making, including resource-mediated movements, yet the mechanisms whereby social information is integrated physiologically to affect such decisions remain unknown. Social information is known to influence the physiological response to food reduction in captive songbirds. Red crossbills (Loxia curvirostra) that were food reduced for several days showed significant elevations in circulating corticosterone (a "stress" hormone often responsive to food limitation) only if their neighbors were similarly food restricted. Physiological responses to glucocorticoid hormones are enacted through two receptors that may be expressed differentially in target tissues. Therefore, we investigated the influence of social information on the expression of the mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) mRNA in captive red crossbill brains. Although the role of MR and GR in the response to social information may be highly complex, we specifically predicted social information from food-restricted individuals would reduce MR and GR expression in two brain regions known to regulate hypothalamic-pituitary-adrenal (HPA) activity - given that reduced receptor expression may lessen the efficacy of negative feedback and release inhibitory tone on the HPA. Our results support these predictions - offering one potential mechanism whereby social cues could increase or sustain HPA-activity during stress. The data further suggest different mechanisms by which metabolic stress versus social information influence HPA activity and behavioral outcomes. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Nuclear receptor DHR4 controls the timing of steroid hormone pulses during Drosophila development.

    Directory of Open Access Journals (Sweden)

    Qiuxiang Ou

    2011-09-01

    Full Text Available In insects, precisely timed periodic pulses of the molting hormone ecdysone control major developmental transitions such as molts and metamorphosis. The synthesis and release of ecdysone, a steroid hormone, is itself controlled by PTTH (prothoracicotopic hormone. PTTH transcript levels oscillate with an 8 h rhythm, but its significance regarding the timing of ecdysone pulses is unclear. PTTH acts on its target tissue, the prothoracic gland (PG, by activating the Ras/Raf/ERK pathway through its receptor Torso, however direct targets of this pathway have yet to be identified. Here, we demonstrate that Drosophila Hormone Receptor 4 (DHR4, a nuclear receptor, is a key target of the PTTH pathway and establishes temporal boundaries by terminating ecdysone pulses. Specifically, we show that DHR4 oscillates between the nucleus and cytoplasm of PG cells, and that the protein is absent from PG nuclei at developmental times when low titer ecdysone pulses occur. This oscillatory behavior is blocked when PTTH or torso function is abolished, resulting in nuclear accumulation of DHR4, while hyperactivating the PTTH pathway results in cytoplasmic retention of the protein. Increasing DHR4 levels in the PG can delay or arrest development. In contrast, reducing DHR4 function in the PG triggers accelerated development, which is caused by precocious ecdysone signaling due to a failure to repress ecdysone pulses. Finally, we show that DHR4 negatively regulates the expression of a hitherto uncharacterized cytochrome P450 gene, Cyp6t3. Disruption of Cyp6t3 function causes low ecdysteroid titers and results in heterochronic phenotypes and molting defects, indicating a novel role in the ecdysone biosynthesis pathway. We propose a model whereby nuclear DHR4 controls the duration of ecdysone pulses by negatively regulating ecdysone biosynthesis through repression of Cyp6t3, and that this repressive function is temporarily overturned via the PTTH pathway by removing DHR4

  13. Activation of Penile Proadipogenic Peroxisome Proliferator-Activated Receptor with an Estrogen: Interaction with Estrogen Receptor Alpha during Postnatal Development

    Directory of Open Access Journals (Sweden)

    Mahmoud M. Mansour

    2008-01-01

    Full Text Available Exposure to the estrogen receptor alpha (ER ligand diethylstilbesterol (DES between neonatal days 2 to 12 induces penile adipogenesis and adult infertility in rats. The objective of this study was to investigate the in vivo interaction between DES-activated ER and the proadipogenic transcription factor peroxisome proliferator-activated receptor gamma (PPAR. Transcripts for PPARs , , and and 1a splice variant were detected in Sprague-Dawley normal rat penis with PPAR predominating. In addition, PPAR1b and PPAR2 were newly induced by DES. The PPAR transcripts were significantly upregulated with DES and reduced by antiestrogen ICI 182, 780. At the cellular level, PPAR protein was detected in urethral transitional epithelium and stromal, endothelial, neuronal, and smooth muscular cells. Treatment with DES activated ER and induced adipocyte differentiation in corpus cavernosum penis. Those adipocytes exhibited strong nuclear PPAR expression. These results suggest a biological overlap between PPAR and ER and highlight a mechanism for endocrine disruption.

  14. Antibody Probes to Estrogen Receptor-alpha Transcript-Specific Upstream Peptides: Alternates ER-alpha Promoter Use and Breast Cancer Etiology/Outcome

    Science.gov (United States)

    2005-05-01

    cells recovered in the expressed milk of lactating healthy donors as part of a biomarkers study. Preparing for potential handling of ductal lavage...specificity for the assay (Fig. 17). It is quite feasible to isolate sufficient cells from milk samples and our potential collaorator’s lab was able...Speirs, V., 2001. Expression of alternatively spliced estrogen Uht , R.M., Webb, P., 2000. Estrogen receptor pathways to AP-I. J. receptor alpha mRNAs is

  15. In vivo multiplex quantitative analysis of 3 forms of alpha melanocyte stimulating hormone in pituitary of prolyl endopeptidase deficient mice

    Directory of Open Access Journals (Sweden)

    Perroud Bertrand

    2009-06-01

    Full Text Available Abstract Background In vitro reactions are useful to identify putative enzyme substrates, but in vivo validation is required to identify actual enzyme substrates that have biological meaning. To investigate in vivo effects of prolyl endopeptidase (PREP, a serine protease, on alpha melanocyte stimulating hormone (α-MSH, we developed a new mass spectrometry based technique to quantitate, in multiplex, the various forms of α-MSH. Methods Using Multiple Reaction Monitoring (MRM, we analyzed peptide transitions to quantify three different forms of α-MSH. Transitions were first confirmed using standard peptides. Samples were then analyzed by mass spectrometry using a triple quadrupole mass spectrometer, after elution from a reverse phase C18 column by a gradient of acetonitrile. Results We first demonstrate in vitro that PREP digests biological active alpha melanocyte stimulating hormone (α-MSH1–13, by cleaving the terminal amidated valine and releasing a truncated alpha melanocyte stimulating hormone (α-MSH1–12 product – the 12 residues α-MSH form. We then use the technique in vivo to analyze the MRM transitions of the three different forms of α-MSH: the deacetylated α-MSH1–13, the acetylated α-MSH1–13 and the truncated form α-MSH1–12. For this experiment, we used a mouse model (PREP-GT in which the serine protease, prolyl endopeptidase, is deficient due to a genetrap insertion. Here we report that the ratio between acetylated α-MSH1–13 and α-MSH1–12 is significantly increased (P-value = 0.015, N = 6 in the pituitaries of PREP-GT mice when compared to wild type littermates. In addition no significant changes were revealed in the relative level of α-MSH1–13 versus the deacetylated α-MSH1–13. These results combined with the demonstration that PREP digests α-MSH1–13 in vitro, strongly suggest that α-MSH1–13 is an in vivo substrate of PREP. Conclusion The multiplex targeted quantitative peptidomics technique we

  16. A missense mutation in the second transmembrane segment of the luteinizing hormone receptor causes familial male-limited precocious puberty

    Energy Technology Data Exchange (ETDEWEB)

    Kraaij, R.; Post, M.; Grootegoed, J.A. [Erasmus Univ. Rotterdam (Netherlands)] [and others

    1995-10-01

    Patients with familial male-limited precocious puberty present with early onset of puberty. Several missense mutations in the LH receptor gene that cause amino acid substitutions in the sixth transmembrane segment of the receptor protein have been shown to be a cause of the disorder. We have identified a novel LH receptor gene mutation in a patient with familial male-limited precocious puberty that results in a threonine for methionine substitution at position 398 in the second transmembrane segment of the receptor protein. In vitro expression in human embryonic kidney 293 cells of this LH receptor mutant and two previously described LH receptor mutants showed that cAMP production in the absence of hormone was elevated up to 25-fold compared to the basal level of the wild-type receptor. The ED{sub 50} values of hormone-induced cAMP production was relatively low for mutant receptors. We also produced receptors containing amino acid substitutions in both the second and sixth transmembrane segments. For these double mutants, basal receptor activities were similar to the basal activities observed in single mutants, whereas hormone-induced receptor activation was almost completely abolished. 31 refs., 2 figs.

  17. Thyroid hormone modulates inotropic responses, alpha-adrenoceptor density and catecholamine concentrations in the rat heart

    NARCIS (Netherlands)

    Zwaveling, J.; Batink, H. D.; de Jong, J.; Winkler Prins, E. A.; Pfaffendorf, M.; van Zwieten, P. A.

    1996-01-01

    We investigated the influence of hyper- and hypothyroidism on basal parameters of isolated perfused hearts of rats. In addition the effects of different extracellular calcium concentrations ([Ca2+]o), the calcium entry promoter Bay K8644 and the alpha 1-adrenoceptor agonist methoxamine were

  18. Analyzing the Role of Receptor Internalization in the Regulation of Melanin-Concentrating Hormone Signaling

    Directory of Open Access Journals (Sweden)

    Jay I. Moden

    2013-01-01

    Full Text Available The regulation of appetite is complex, though our understanding of the process is improving. The potential role for the melanin-concentrating hormone (MCH signaling pathway in the treatment of obesity is being explored by many. It was hypothesized that internalization of MCH receptors would act to potently desensitize cells to MCH. Despite potent desensitization of ERK signaling by MCH in BHK-570 cells, we were unable to observe MCH-mediated internalization of MCH receptor 1 (MCHR1 by fluorescence microscopy. A more quantitative approach using a cell-based ELISA indicated only 15% of receptors internalized, which is much lower than that reported in the literature. When -arrestins were overexpressed in our system, removal of receptors from the cell surface was facilitated and signaling to a leptin promoter was diminished, suggesting that internalization of MCHR1 is sensitive to cellular -arrestin levels. A dominant-negative GRK construct completely inhibited loss of receptors from the cell surface in response to MCH, suggesting that the internalization observed is phosphorylation-dependent. Since desensitization of MCH-mediated ERK signaling did not correlate with significant loss of MCHR1 from the cell surface, we hypothesize that in this model system regulation of MCH signaling may be the result of segregation of receptors from signaling components at the plasma membrane.

  19. Nuclear hormone receptor NHR-49 controls fat consumption and fatty acid composition in C. elegans.

    Directory of Open Access Journals (Sweden)

    Marc R Van Gilst

    2005-02-01

    Full Text Available Mammalian nuclear hormone receptors (NHRs, such as liver X receptor, farnesoid X receptor, and peroxisome proliferator-activated receptors (PPARs, precisely control energy metabolism. Consequently, these receptors are important targets for the treatment of metabolic diseases, including diabetes and obesity. A thorough understanding of NHR fat regulatory networks has been limited, however, by a lack of genetically tractable experimental systems. Here we show that deletion of the Caenorhabditis elegans NHR gene nhr-49 yielded worms with elevated fat content and shortened life span. Employing a quantitative RT-PCR screen, we found that nhr-49 influenced the expression of 13 genes involved in energy metabolism. Indeed, nhr-49 served as a key regulator of fat usage, modulating pathways that control the consumption of fat and maintain a normal balance of fatty acid saturation. We found that the two phenotypes of the nhr-49 knockout were linked to distinct pathways and were separable: The high-fat phenotype was due to reduced expression of enzymes in fatty acid beta-oxidation, and the shortened adult life span resulted from impaired expression of a stearoyl-CoA desaturase. Despite its sequence relationship with the mammalian hepatocyte nuclear factor 4 receptor, the biological activities of nhr-49 were most similar to those of the mammalian PPARs, implying an evolutionarily conserved role for NHRs in modulating fat consumption and composition. Our findings in C. elegans provide novel insights into how NHR regulatory networks are coordinated to govern fat metabolism.

  20. Affinity of the enantiomers of. alpha. - and. beta. -cyclazocine for binding to the phencyclidine and. mu. opioid receptors

    Energy Technology Data Exchange (ETDEWEB)

    Todd, S.L.; Balster, R.L.; Martin, B.R. (Virginia Commonwealth Univ., Richmond (USA))

    1990-01-01

    The enantiomers in the {alpha} and {beta} series of cyclazocine were evaluated for their ability to bind to phencyclidine (PCP) and {mu}-opioid receptors in order to determine their receptor selectivity. The affinity of (-)-{beta}-cyclazocine for the PCP receptor was 1.5 greater than PCP itself. In contrast, (-)-{alpha}-cyclazocine, (+)-{alpha}-cyclazocine, and (+)-{beta}-cyclazocine were 3-, 5- and 138-fold less potent than PCP, respectively. Scatchard analysis of saturable binding of ({sup 3}H)Tyr-D-Ala-Gly-N-MePhe-Gly-ol (DAMGO) also exhibited a homogeneous population of binding sites with an apparent K{sub D} of 1.9 nM and an estimated Bmax of 117 pM. (3H)Tyr-D-Ala-Gly-N-MePhe-Gly-ol (DAMGO) binding studies revealed that (-)-{alpha}-cyclazocine (K{sub D} = 0.48 nM) was 31-, 1020- and 12,600-fold more potent than (-)-{beta}-cyclazocine, (+)-{alpha}-cyclazocine and (+)-{beta}-cyclazocine, respectively, for binding to the {mu}-opioid receptor. These data show that, although (-)-{beta}-cyclazocine is a potent PCP receptor ligand consistent with its potent PCP-like discriminative stimulus effects, it shows little selectivity for PCP receptor since it also potently displaces {mu}-opioid binding. However, these cyclazocine isomers, due to their extraordinary degree of stereoselectivity, may be useful in characterizing the structural requirements for benzomorphans having activity at the PCP receptor.

  1. Nonequivalence of alpha-bungarotoxin binding sites in the native nicotinic receptor molecule

    Energy Technology Data Exchange (ETDEWEB)

    Conti-Tronconi, B.M.; Tang, F.; Walgrave, S.; Gallagher, W. (Univ. of Minnesota, St. Paul (USA))

    1990-01-30

    In the native, membrane-bound form of the nicotinic acetylcholine receptor (M-AcChR) the two sites for the cholinergic antagonist alpha-bungarotoxin (alpha-BGT) have different binding properties. One site has high affinity, and the M-AcChR/alpha-BGT complexes thus formed dissociate very slowly, similar to the complexes formed with detergent-solubilized AcChR (S-AcChR). The second site has much lower affinity (KD approximately 59 +/- 35 nM) and forms quickly reversible complexes. The nondenaturing detergent Triton X-100 is known to solubilize the AcChR in a form unable, upon binding of cholinergic ligands, to open the ion channel and to become desensitized. Solubilization of the AcChR in Triton X-100 affects the binding properties of this second site and converts it to a high-affinity, slowly reversible site. Prolonged incubation of M-AcChR at 4 degrees C converts the low-affinity site to a high-affinity site similar to those observed in the presence of Triton X-100. Although the two sites have similar properties when the AcChR is solubilized in Triton X-100, their nonequivalence can be demonstrated by the effect on alpha-BGT binding of concanavalin A, which strongly reduces the association rate of one site only. The Bmax of alpha-BGT to either Triton-solubilized AcChR or M-AcChR is not affected by the presence of concanavalin A. Occupancy of the high-affinity, slowly reversible site in M-AcChR inhibits the Triton X-100 induced conversion to irreversibility of the second site. At difference with alpha-BGT, the long alpha-neurotoxin from Naja naja siamensis venom (alpha-NTX) binds with high affinity and in a very slowly reversible fashion to two sites in the M-AcChR. We confirm here that Triton-solubilized AcChR or M-AcChR binds in a very slowly reversible fashion the same amount of alpha-NTX.

  2. Functional discrepancies between tumor necrosis factor and lymphotoxin alpha explained by trimer stability and distinct receptor interactions

    DEFF Research Database (Denmark)

    Schuchmann, M; Hess, S; Bufler, P

    1995-01-01

    Tumor necrosis factor (TNF) and lymphotoxin alpha (LT alpha) are closely related cytokines which bind with nearly identical affinities to the same pair of cell surface receptors, p55 and p75TNFR. Therefore it is assumed that TNF and LT alpha are redundant cytokines. This study, however, demonstra......Tumor necrosis factor (TNF) and lymphotoxin alpha (LT alpha) are closely related cytokines which bind with nearly identical affinities to the same pair of cell surface receptors, p55 and p75TNFR. Therefore it is assumed that TNF and LT alpha are redundant cytokines. This study, however......, demonstrates that TNF and LT alpha differ significantly with regard to their mitogenic and cytotoxic potentials. LT alpha's superior mitogenic effect could be explained by its formation of a more stable trimer. In contrast to the TNF trimer, which disintegrated under physiological conditions into biologically...... inactive monomers, the LT alpha trimer remained stable for several days. Accordingly, LT alpha more effectively induced fibroblast growth which demands long-term presence of the cytokine. TNF's superior cytotoxicity, which requires only short-term impact of the cytokine, could be attributed to a distinct...

  3. The selective estrogen receptor-alpha coactivator, RPL7, and sexual differentiation of the songbird brain.

    Science.gov (United States)

    Duncan, Kelli A; Jimenez, Pedro; Carruth, Laura L

    2009-12-01

    The brain and behavior of the Australian zebra finch (Taeniopygia guttata) are sexually dimorphic. Only males sing courtship songs and the regions of the brain involved in the learning and production of song are significantly larger in males than females. Therefore the zebra finch serves as an excellent model for studying the mechanisms that influence brain sexual differentiation, and the majority of past research on this system has focused on the actions of steroid hormones in the development of these sex differences. Coregulators, such as coactivators and corepressors, are proteins and RNA activators that work by enhancing or depressing the transcriptional activity of the nuclear steroid receptor with which they associate, and thereby modulating the development of sex-specific brain morphologies and behaviors. The actions of these proteins may help elucidate the hormonal mechanisms that underlie song nuclei development. Research described in this review focus on the role of estrogen receptor coactivators in the avian brain; more specifically we will focus on the role of RPL7 (ribosomal protein L7; also known as L7/SPA) on sexual differentiation of the zebra finch song system. Collectively, these studies provide information about the role of steroid receptor coactivators on development of the zebra finch song system as well as on sexual differentiation of brain.

  4. [Advanced luminal breast cancer (hormone receptor-positive, HER2 negative): New therapeutic options in 2015].

    Science.gov (United States)

    Vanacker, Hélène; Bally, Olivia; Kassem, Loay; Tredan, Olivier; Heudel, Pierre; Bachelot, Thomas

    2015-06-01

    Despite improvements in early detection, surgery and systemic therapy, metastatic breast cancer remains a major cause of death. Luminal type breast cancers expressing hormone estrogen receptor (ER) or progesterone (PR) and without HER2 overexpression are generally sensitive to endocrine therapy, but raise the issue of the occurrence of resistance to treatment, particularly at metastatic stage. A better understanding of hormone resistance may guide the development of new therapeutics. New strategies aim at enhancing and prolonging of endocrine sensitivity, by optimizing existing schemes, or by combining an endocrine therapy with a targeted therapies specific to hormone resistance pathways: ER signaling, PI3K/AKT/mTOR and Cyclin Dependent Kinase (CDK). Key corners of 2014 include confirmation of benefit of high dose fulvestrant, and commercialization of everolimus as the first mTOR inhibitor in this indication. Other strategies are being tested dealing with new endocrine therapies or new molecular targets such as PI3K inhibitors, insulin-like growth factor receptor (IGF-R) and histone deacetylase (HDAC) inhibitors. Coming years may be fruitful and might radically change our way to treat these patients. Copyright © 2015 Société Françise du Cancer. Publié par Elsevier Masson SAS. Tous droits réservés. Published by Elsevier Masson SAS. All rights reserved.

  5. Molecular genetic studies of bipolar disorder and puerperal psychosis at two polymorphisms in the estrogen receptor alpha gene (ESR 1).

    Science.gov (United States)

    Jones, I; Middle, F; McCandless, F; Coyle, N; Robertson, E; Brockington, I; Lendon, C; Craddock, N

    2000-12-04

    A number of lines of evidence point to the possible involvement of estrogen pathways in the pathophysiology of bipolar disorder in general and puerperal psychosis in particular. There is strong evidence from clinical, follow-up, and genetic studies to support the hypothesis that most cases of puerperal psychosis are manifestations of an affective disorder diathesis with a puerperal trigger and that genes influence susceptibility to both diathesis and trigger. The nature of the trigger is unknown but in view of the abrupt onset at a time of major physiological change it is widely believed that biological, probably hormonal, mechanisms are of paramount importance, with estrogen receiving the most attention to date. We have undertaken a case control association study of bipolar disorder and puerperal psychosis at two known polymorphisms within the estrogen receptor alpha gene (ESR 1) in a sample of 219 unrelated bipolar probands and 219 controls. We could exclude these polymorphisms from an important contribution to susceptibility to bipolar disorder with a high level of confidence. We found no support for the hypothesis that they contribute specific susceptibility to the puerperal trigger, but due to the small numbers of puerperal probands (n = 26) no firm conclusions can be drawn regarding their involvement in puerperal psychosis. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:850-853, 2000. Copyright 2000 Wiley-Liss, Inc.

  6. Assessment of hormone-like activities in Ginkgo biloba, Elettaria cardamomum and Plantago ovata extracts using in vitro receptor-specific bioassays.

    Science.gov (United States)

    Real, Macarena; Molina-Molina, José-Manuel; Jimenez, Jesús; Diéguez, Horacio R; Fernández, Mariana F; Olea, Nicolás

    2015-01-01

    Medicinal plants are widely used for the treatment of diseases and for the development of new drugs. This study was designed to determine the presence of hormone-like activities dependent on the activation of human estrogen receptor alpha (hERa) and/or androgen receptor (hAR) in methanol extracts prepared from three medicinal plants historically and currently used for therapeutic purposes: Ginkgo biloba leaves (GBL), Elettaria cardamomum seeds (ECS) and Plantago ovata seeds (POS). After a solid-liquid extraction (SLE) step, their effects on hERa function were assessed in MCF-7 breast cancer cells using the E-Screen bioassay, and their ability to induce hAR-mediated reporter gene expression was evaluated using the androgen-sensitive stable prostatic PALM cell line. Unlike POS extracts, GBL and ECS extracts showed estrogenic (0.07 and 0.20 nM E2Eq mg(-1), respectively) and anti-estrogenic (0.01 and 0.02 μM ICI182780Eq mg(-1), respectively) activities. ECS extracts evidenced androgenic activity (0.30 nM R1881Eq mg(-1)) and POS extracts anti-androgenic activity (22.30 μM ProcEq mg(-1)). According to these findings, these plant extracts may interfere with the endocrine system via one or more hormonal receptors, and further investigation is warranted into their role as endocrine disrupters in humans.

  7. Identification of Thyroid Hormones and Functional Characterization of Thyroid Hormone Receptor in the Pacific Oyster Crassostrea gigas Provide Insight into Evolution of the Thyroid Hormone System.

    Science.gov (United States)

    Huang, Wen; Xu, Fei; Qu, Tao; Zhang, Rui; Li, Li; Que, Huayong; Zhang, Guofan

    2015-01-01

    Thyroid hormones (THs) play important roles in development, metamorphosis, and metabolism in vertebrates. During the past century, TH functions were regarded as a synapomorphy of vertebrates. More recently, accumulating evidence has gradually convinced us that TH functions also occur in invertebrate chordates. To date, however, TH-related studies in non-chordate invertebrates have been limited. In this study, THs were qualitatively detected by two reliable methods (HPLC and LC/MS) in a well-studied molluscan species, the Pacific oyster Crassostrea gigas. Quantitative measurement of THs during the development of C. gigas showed high TH contents during embryogenesis and that oyster embryos may synthesize THs endogenously. As a first step in elucidating the TH signaling cascade, an ortholog of vertebrate TH receptor (TR), the most critical gene mediating TH effects, was cloned in C. gigas. The sequence of CgTR has conserved DNA-binding and ligand-binding domains that normally characterize these receptors. Experimental results demonstrated that CgTR can repress gene expression through binding to promoters of target genes and can interact with oyster retinoid X receptor. Moreover, CgTR mRNA expression was activated by T4 and the transcriptional activity of CgTR promoter was repressed by unliganded CgTR protein. An atypical thyroid hormone response element (CgDR5) was found in the promoter of CgTR, which was verified by electrophoretic mobility shift assay (EMSA). These results indicated that some of the CgTR function is conserved. However, the EMSA assay showed that DNA binding specificity of CgTR was different from that of the vertebrate TR and experiments with two dual-luciferase reporter systems indicated that l-thyroxine, 3,3',5-triiodothyronine, and triiodothyroacetic acid failed to activate the transcriptional activity of CgTR. This is the first study to functionally characterize TR in mollusks. The presence of THs and the functions of CgTR in mollusks contribute

  8. Identification of Thyroid Hormones and Functional Characterization of Thyroid Hormone Receptor in the Pacific Oyster Crassostrea gigas Provide Insight into Evolution of the Thyroid Hormone System.

    Directory of Open Access Journals (Sweden)

    Wen Huang

    Full Text Available Thyroid hormones (THs play important roles in development, metamorphosis, and metabolism in vertebrates. During the past century, TH functions were regarded as a synapomorphy of vertebrates. More recently, accumulating evidence has gradually convinced us that TH functions also occur in invertebrate chordates. To date, however, TH-related studies in non-chordate invertebrates have been limited. In this study, THs were qualitatively detected by two reliable methods (HPLC and LC/MS in a well-studied molluscan species, the Pacific oyster Crassostrea gigas. Quantitative measurement of THs during the development of C. gigas showed high TH contents during embryogenesis and that oyster embryos may synthesize THs endogenously. As a first step in elucidating the TH signaling cascade, an ortholog of vertebrate TH receptor (TR, the most critical gene mediating TH effects, was cloned in C. gigas. The sequence of CgTR has conserved DNA-binding and ligand-binding domains that normally characterize these receptors. Experimental results demonstrated that CgTR can repress gene expression through binding to promoters of target genes and can interact with oyster retinoid X receptor. Moreover, CgTR mRNA expression was activated by T4 and the transcriptional activity of CgTR promoter was repressed by unliganded CgTR protein. An atypical thyroid hormone response element (CgDR5 was found in the promoter of CgTR, which was verified by electrophoretic mobility shift assay (EMSA. These results indicated that some of the CgTR function is conserved. However, the EMSA assay showed that DNA binding specificity of CgTR was different from that of the vertebrate TR and experiments with two dual-luciferase reporter systems indicated that l-thyroxine, 3,3',5-triiodothyronine, and triiodothyroacetic acid failed to activate the transcriptional activity of CgTR. This is the first study to functionally characterize TR in mollusks. The presence of THs and the functions of CgTR in

  9. Gender dependent association between perinatal morbidity and estrogen receptor-alpha Pvull polymorphism.

    Science.gov (United States)

    Derzbach, László; Treszl, András; Balogh, Adám; Vásárhelyi, Barna; Tulassay, Tivadar; Rigó J, János

    2005-01-01

    Assuming the importance of estrogen in perinatal physiology, we tested the association of an estrogen receptor-alpha (ER-alpha) gene Pvull pP polymorphism with perinatal morbidity in premature infants. The ER-alpha Pp genotype was determined in 69 low-birth weight (LBW) boys and 72 LBW girls, 86 term boys and 81 term girls. The association between risk factors, genotype, gender and perinatal morbidity was tested with binary logistic regression analysis. Boys carrying "p" allele were at lower risk for necrotizing enterocolitis (OR [95% Cl]: 0.24 [0.07-0.83]) and patent ductus arteriosus (OR [95% Cl]: 0.24 [0.05-0.97]). The carrier state of the "p" allele was associated with a 34-h shorter period of oxygen supplementation on average (P=0.0018). Boys with pp genotype were at greater risk for intraventricular hemorrhage (OR [95% Cl]: 4.39 [1.15-16.82]). No association between ER-alpha Pvull polymorphism and morbidity was present in girls. Since homozygocity for any Pvull alleles (i.e. having PP or pp genotype) increases the risk for at least one of the most common perinatal complications, it is likely that the heterozygous carrier state of Pvull genotypes has a protective effect, which is gender-dependent.

  10. Growth hormone receptor C-terminal domains required for growth hormone-induced intracellular free Ca2+ oscillations and gene transcription

    DEFF Research Database (Denmark)

    Billestrup, N; Bouchelouche, P; Allevato, G

    1995-01-01

    The biological effects of growth hormone (GH) are initiated by its binding to the GH receptor (GHR) followed by association and activation of the tyrosine kinase JAK2. Here we report that GH can stimulate an increase in intracellular free Ca2+ concentration ([Ca2+]i) in cells expressing wild-type...

  11. Identification and validation of the pathways and functions regulated by the orphan nuclear receptor, ROR alpha1, in skeletal muscle.

    Science.gov (United States)

    Raichur, S; Fitzsimmons, R L; Myers, S A; Pearen, M A; Lau, P; Eriksson, N; Wang, S M; Muscat, G E O

    2010-07-01

    The retinoic acid receptor-related orphan receptor (ROR) alpha has been demonstrated to regulate lipid metabolism. We were interested in the ROR alpha 1 dependent physiological functions in skeletal muscle. This major mass organ accounts for approximately 40% of the total body mass and significant levels of lipid catabolism, glucose disposal and energy expenditure. We utilized the strategy of targeted muscle-specific expression of a truncated (dominant negative) ROR alpha 1 Delta DE in transgenic mice to investigate ROR alpha 1 signaling in this tissue. Expression profiling and pathway analysis indicated that ROR alpha influenced genes involved in: (i) lipid and carbohydrate metabolism, cardiovascular and metabolic disease; (ii) LXR nuclear receptor signaling and (iii) Akt and AMPK signaling. This analysis was validated by quantitative PCR analysis using TaqMan low-density arrays, coupled to statistical analysis (with Empirical Bayes and Benjamini-Hochberg). Moreover, westerns and metabolic profiling were utilized to validate the genes, proteins and pathways (lipogenic, Akt, AMPK and fatty acid oxidation) involved in the regulation of metabolism by ROR alpha 1. The identified genes and pathways were in concordance with the demonstration of hyperglycemia, glucose intolerance, attenuated insulin-stimulated phosphorylation of Akt and impaired glucose uptake in the transgenic heterozygous Tg-ROR alpha 1 Delta DE animals. In conclusion, we propose that ROR alpha 1 is involved in regulating the Akt2-AMPK signaling pathways in the context of lipid homeostasis in skeletal muscle.

  12. Serum calcium, tumor size, and hormone receptor status in women with untreated breast cancer.

    Science.gov (United States)

    Thaw, Sunn Sunn H; Sahmoun, Abe; Schwartz, Gary G

    2012-05-01

    Elevated serum levels of calcium are frequently observed in advanced breast cancer, but data on serum calcium and breast cancer characteristics at the time of breast cancer diagnosis are limited. We conducted a cross-sectional study of 555 women with newly-diagnosed, untreated breast cancer in North Dakota. We examined the relationship between tumor size, serum calcium and other clinical characteristics of breast tumors, including age and hormone receptor status, using multiple linear regressions. Tumors that were estrogen receptor negative tended to be associated with higher serum calcium levels (p = 0.07). We observed a significant positive correlation between tumor volume and serum calcium levels (adjusted for patient age, body mass index, hormonal receptors, stage at diagnosis, and grade). The association between tumor volume and serum calcium was limited to post-menopausal women. Our finding that postmenopausal women with larger breast tumors had significantly higher serum calcium levels is consistent with a calciotropic effect of early breast cancer in postmenopausal women.

  13. Insulin-Insulin-like Growth Factors Hybrids as Molecular Probes of Hormone:Receptor Binding Specificity.

    Science.gov (United States)

    Křížková, Květoslava; Chrudinová, Martina; Povalová, Anna; Selicharová, Irena; Collinsová, Michaela; Vaněk, Václav; Brzozowski, Andrzej M; Jiráček, Jiří; Žáková, Lenka

    2016-05-31

    Insulin, insulin-like growth factors 1 and 2 (IGF-1 and -2, respectively), and their receptors (IR and IGF-1R) are the key elements of a complex hormonal system that is essential for the development and functioning of humans. The C and D domains of IGFs (absent in insulin) likely play important roles in the differential binding of IGF-1 and -2 to IGF-1R and to the isoforms of IR (IR-A and IR-B) and specific activation of these receptors. Here, we attempted to probe the impact of IGF-1 and IGF-2 D domains (DI and DII, respectively) and the IGF-2 C domain (CII) on the receptor specificity of these hormones. For this, we made two types of insulin hybrid analogues: (i) with the C-terminus of the insulin A chain extended by the amino acids from the DI and DII domains and (ii) with the C-terminus of the insulin B chain extended by some amino acids derived from the CII domain. The receptor binding affinities of these analogues and their receptor autophosphorylation potentials were characterized. Our results indicate that the DI domain has a more negative impact than the DII domain does on binding to IR, and that the DI domain Pro-Leu-Lys residues are important factors for a different IR-A versus IR-B binding affinity of IGF-1. We also showed that the additions of amino acids that partially "mimic" the CII domain, to the C-terminus of the insulin B chain, change the binding and autophosphorylation specificity of insulin in favor of the "metabolic" IR-B isoform. This opens new venues for rational enhancement of insulin IR-B specificity by modifications beyond the C-terminus of its B chain.

  14. A novel ubiquitously expressed alpha-latrotoxin receptor is a member of the CIRL family of G-protein-coupled receptors.

    Science.gov (United States)

    Ichtchenko, K; Bittner, M A; Krasnoperov, V; Little, A R; Chepurny, O; Holz, R W; Petrenko, A G

    1999-02-26

    Poisoning with alpha-latrotoxin, a neurotoxic protein from black widow spider venom, results in a robust increase of spontaneous synaptic transmission and subsequent degeneration of affected nerve terminals. The neurotoxic action of alpha-latrotoxin involves extracellular binding to its high affinity receptors as a first step. One of these proteins, CIRL, is a neuronal G-protein-coupled receptor implicated in the regulation of secretion. We now demonstrate that CIRL has two close homologs with a similar domain structure and high degree of overall identity. These novel receptors, which we propose to name CIRL-2 and CIRL-3, together with CIRL (CIRL-1) belong to a recently identified subfamily of large orphan receptors with structural features typical of both G-protein-coupled receptors and cell adhesion proteins. Northern blotting experiments indicate that CIRL-2 is expressed ubiquitously with highest concentrations found in placenta, kidney, spleen, ovary, heart, and lung, whereas CIRL-3 is expressed predominantly in brain similarly to CIRL-1. It appears that CIRL-2 can also bind alpha-latrotoxin, although its affinity to the toxin is about 14 times less than that of CIRL-1. When overexpressed in chromaffin cells, CIRL-2 increases their sensitivity to alpha-latrotoxin stimulation but also inhibits Ca2+-regulated secretion. Thus, CIRL-2 is a functionally competent receptor of alpha-latrotoxin. Our findings suggest that although the nervous system is the primary target of low doses of alpha-latrotoxin, cells of other tissues are also susceptible to the toxic effects of alpha-latrotoxin because of the presence of CIRL-2, a low affinity receptor of the toxin.

  15. Effects of transgenic overexpression of diapause hormone and diapause hormone receptor genes on non-diapause silkworm.

    Science.gov (United States)

    Gong, Chunying; Zeng, Wenhui; Zhang, Tianyang; Liu, Rongpeng; Ou, Yao; Ai, Junwen; Xiang, Zhonghuai; Xu, Hanfu

    2017-12-01

    Diapause is a state of developmental arrest that is most often observed in arthropods, especially insects. The domesticated silkworm, Bombyx mori, is a typical insect that enters diapause at an early embryonic stage. Previous studies have revealed that the diapause hormone (DH) signaling molecules, especially the core members DH and DH receptor 1 (DHR1), are crucial for the determination of embryonic diapause in diapause silkworm strains. However, whether they function in non-diapause silkworm strains remains largely unknown. Here, we generated two transgenic lines overexpressing DH or DHR1 genes in a non-diapause silkworm strain, Nistari. Our results showed that developmental expression patterns of DH and DHR1 are quite similar in transgenic silkworms: both genes are highly expressed in the mid to late stages of pupae and are most highly expressed in day-6 pupae but are expressed at very low levels in other developmental stages. Moreover, the overexpression of DH or DHR1 can affect the expression of diapause-related genes but is not sufficient to induce embryonic diapause in their offspring. This study provides new insights into the function of DH and DHR1 in a non-diapause silkworm strain.

  16. Role of the proteasome in the regulation of estrogen receptor alpha turnover and function in MCF-7 breast carcinoma cells.

    Science.gov (United States)

    Laïos, Ioanna; Journé, Fabrice; Nonclercq, Denis; Vidal, Doris Salazar; Toillon, Robert-Alain; Laurent, Guy; Leclercq, Guy

    2005-03-01

    Estrogen receptor alpha (ER) turnover in MCF-7 cells was assessed by pulse chase analysis and measurement of ER steady-state level. In untreated cells, degradation of (35)S-labeled ER was characterized by a slow phase followed by a more rapid decline. Without ligand, ER elimination was totally compensated by synthesis which maintained receptor homeostasis. Estradiol (E(2)) and the pure antiestrogen RU 58,668 abolished the slow phase of ER breakdown and enhanced the degradation of neosynthesized ER, producing a low ER steady-state level. By contrast, the partial antiestrogen OH-Tam was ineffective in this respect and caused ER accumulation. Regardless of the conditions, ER breakdown was abolished by proteasome inhibition (MG-132). ER ligands decreased cell capacity to bind [(3)H]E(2), even in the presence of MG-132, indicating that the regulation of ER level and E(2) binding capacity occurs through distinct mechanisms. MG-132 partially blocked the basal transcription of an ERE-dependent reporter gene and modified the ability of E(2) to induce the expression of the latter: the hormone was unable to restore the transactivation activity measured without MG-132. RU 58,668 and OH-Tam failed to enhance the inhibitory action of MG-132, suggesting that a loss of basal ER-mediated transactivation mainly affects the stimulatory effect of estrogens. Overall, our findings reveal that ER steady state level, ligand binding capacity and transactivation potency fit in a complex regulatory scheme involving distinct mechanisms, which may be dissociated from each other under various treatments.

  17. PGC-1{beta} regulates mouse carnitine-acylcarnitine translocase through estrogen-related receptor {alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Gacias, Mar; Perez-Marti, Albert; Pujol-Vidal, Magdalena; Marrero, Pedro F. [Department of Biochemistry and Molecular Biology, School of Pharmacy and the Institute of Biomedicine of the University of Barcelona (IBUB) (Spain); Haro, Diego, E-mail: dharo@ub.edu [Department of Biochemistry and Molecular Biology, School of Pharmacy and the Institute of Biomedicine of the University of Barcelona (IBUB) (Spain); Relat, Joana [Department of Biochemistry and Molecular Biology, School of Pharmacy and the Institute of Biomedicine of the University of Barcelona (IBUB) (Spain)

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer The Cact gene is induced in mouse skeletal muscle after 24 h of fasting. Black-Right-Pointing-Pointer The Cact gene contains a functional consensus sequence for ERR. Black-Right-Pointing-Pointer This sequence binds ERR{alpha} both in vivo and in vitro. Black-Right-Pointing-Pointer This ERRE is required for the activation of Cact expression by the PGC-1/ERR axis. Black-Right-Pointing-Pointer Our results add Cact as a genuine gene target of these transcriptional regulators. -- Abstract: Carnitine/acylcarnitine translocase (CACT) is a mitochondrial-membrane carrier proteins that mediates the transport of acylcarnitines into the mitochondrial matrix for their oxidation by the mitochondrial fatty acid-oxidation pathway. CACT deficiency causes a variety of pathological conditions, such as hypoketotic hypoglycemia, cardiac arrest, hepatomegaly, hepatic dysfunction and muscle weakness, and it can be fatal in newborns and infants. Here we report that expression of the Cact gene is induced in mouse skeletal muscle after 24 h of fasting. To gain insight into the control of Cact gene expression, we examine the transcriptional regulation of the mouse Cact gene. We show that the 5 Prime -flanking region of this gene is transcriptionally active and contains a consensus sequence for the estrogen-related receptor (ERR), a member of the nuclear receptor family of transcription factors. This sequence binds ERR{alpha}in vivo and in vitro and is required for the activation of Cact expression by the peroxisome proliferator-activated receptor gamma coactivator (PGC)-1/ERR axis. We also demonstrate that XTC790, the inverse agonist of ERR{alpha}, specifically blocks Cact activation by PGC-1{beta} in C2C12 cells.

  18. Receptors and effects of gut hormones in three osteoblastic cell lines

    Directory of Open Access Journals (Sweden)

    Wilson Peter JM

    2011-07-01

    Full Text Available Abstract Background In recent years the interest on the relationship of gut hormones to bone processes has increased and represents one of the most interesting aspects in skeletal research. The proportion of bone mass to soft tissue is a relationship that seems to be controlled by delicate and subtle regulations that imply "cross-talks" between the nutrient intake and tissues like fat. Thus, recognition of the mechanisms that integrate a gastrointestinal-fat-bone axis and its application to several aspects of human health is vital for improving treatments related to bone diseases. This work analysed the effects of gut hormones in cell cultures of three osteoblastic cell lines which represent different stages in osteoblastic development. Also, this is the first time that there is a report on the direct effects of glucagon-like peptide 2, and obestatin on osteoblast-like cells. Methods mRNA expression levels of five gut hormone receptors (glucose-dependent insulinotropic peptide [GIP], glucagon-like peptide 1 [GLP-1], glucagon-like peptide 2 [GLP-2], ghrelin [GHR] and obestatin [OB] were analysed in three osteoblastic cell lines (Saos-2, TE-85 and MG-63 showing different stages of osteoblast development using reverse transcription and real time polymerase chain reaction. The responses to the gut peptides were studied using assays for cell viability, and biochemical bone markers: alkaline phosphatase (ALP, procollagen type 1 amino-terminal propeptides (P1NP, and osteocalcin production. Results The gut hormone receptor mRNA displayed the highest levels for GIP in Saos-2 and the lowest levels in MG-63, whereas GHR and GPR39 (the putative obestatin receptor expression was higher in TE-85 and MG-63 and lower in Saos-2. GLP-1 and GLP-2 were expressed only in MG-63 and TE-85. Treatment of gut hormones to cell lines showed differential responses: higher levels in cell viability in Saos-2 after GIP, in TE-85 and MG-63 after GLP-1, GLP-2, ghrelin and

  19. Triclocarban mediates induction of xenobiotic metabolism through activation of the constitutive androstane receptor and the estrogen receptor alpha.

    Directory of Open Access Journals (Sweden)

    Mei-Fei Yueh

    Full Text Available Triclocarban (3,4,4'-trichlorocarbanilide, TCC is used as a broad-based antimicrobial agent that is commonly added to personal hygiene products. Because of its extensive use in the health care industry and resistance to degradation in sewage treatment processes, TCC has become a significant waste product that is found in numerous environmental compartments where humans and wildlife can be exposed. While TCC has been linked to a range of health and environmental effects, few studies have been conducted linking exposure to TCC and induction of xenobiotic metabolism through regulation by environmental sensors such as the nuclear xenobiotic receptors (XenoRs. To identify the ability of TCC to activate xenobiotic sensors, we monitored XenoR activities in response to TCC treatment using luciferase-based reporter assays. Among the XenoRs in the reporter screening assay, TCC promotes both constitutive androstane receptor (CAR and estrogen receptor alpha (ERα activities. TCC treatment to hUGT1 mice resulted in induction of the UGT1A genes in liver. This induction was dependent upon the constitutive active/androstane receptor (CAR because no induction occurred in hUGT1Car(-/- mice. Induction of the UGT1A genes by TCC corresponded with induction of Cyp2b10, another CAR target gene. TCC was demonstrated to be a phenobarbital-like activator of CAR in receptor-based assays. While it has been suggested that TCC be classified as an endocrine disruptor, it activates ERα leading to induction of Cyp1b1 in female ovaries as well as in promoter activity. Activation of ERα by TCC in receptor-based assays also promotes induction of human CYP2B6. These observations demonstrate that TCC activates nuclear xenobiotic receptors CAR and ERα both in vivo and in vitro and might have the potential to alter normal physiological homeostasis. Activation of these xenobiotic-sensing receptors amplifies gene expression profiles that might represent a mechanistic base for

  20. Triclocarban Mediates Induction of Xenobiotic Metabolism through Activation of the Constitutive Androstane Receptor and the Estrogen Receptor Alpha

    Science.gov (United States)

    Yueh, Mei-Fei; Li, Tao; Evans, Ronald M.; Hammock, Bruce; Tukey, Robert H.

    2012-01-01

    Triclocarban (3,4,4′-trichlorocarbanilide, TCC) is used as a broad-based antimicrobial agent that is commonly added to personal hygiene products. Because of its extensive use in the health care industry and resistance to degradation in sewage treatment processes, TCC has become a significant waste product that is found in numerous environmental compartments where humans and wildlife can be exposed. While TCC has been linked to a range of health and environmental effects, few studies have been conducted linking exposure to TCC and induction of xenobiotic metabolism through regulation by environmental sensors such as the nuclear xenobiotic receptors (XenoRs). To identify the ability of TCC to activate xenobiotic sensors, we monitored XenoR activities in response to TCC treatment using luciferase-based reporter assays. Among the XenoRs in the reporter screening assay, TCC promotes both constitutive androstane receptor (CAR) and estrogen receptor alpha (ERα) activities. TCC treatment to hUGT1 mice resulted in induction of the UGT1A genes in liver. This induction was dependent upon the constitutive active/androstane receptor (CAR) because no induction occurred in hUGT1Car−/− mice. Induction of the UGT1A genes by TCC corresponded with induction of Cyp2b10, another CAR target gene. TCC was demonstrated to be a phenobarbital-like activator of CAR in receptor-based assays. While it has been suggested that TCC be classified as an endocrine disruptor, it activates ERα leading to induction of Cyp1b1 in female ovaries as well as in promoter activity. Activation of ERα by TCC in receptor-based assays also promotes induction of human CYP2B6. These observations demonstrate that TCC activates nuclear xenobiotic receptors CAR and ERα both in vivo and in vitro and might have the potential to alter normal physiological homeostasis. Activation of these xenobiotic-sensing receptors amplifies gene expression profiles that might represent a mechanistic base for potential human

  1. Molecular cloning, characterisation, and tissue distribution of oestrogen receptor alpha in eelpout (Zoarces viviparus)

    DEFF Research Database (Denmark)

    Andreassen, Thomas K; Skjødt, Karsten; Anglade, Isabelle

    2003-01-01

    A cDNA encoding the eelpout (Zoarces viviparus) oestrogen receptor alpha (eERalpha) has been isolated from eelpout liver, cloned and sequenced. The cDNA contains a complete open reading frame encoding 570 amino acid residues (mw: 63.0 kDa). The amino acid sequence of eERalpha showed a high degree...... contributes to the accumulating evidence that in fish E(2) is not only involved in the regulation of liver specific proteins, but has a much broader range of targets....

  2. Estrogen receptor activation by tobacco smoke condensate in hormonal therapy-resistant breast cancer cells.

    Science.gov (United States)

    Niwa, Toshifumi; Shinagawa, Yuri; Asari, Yosuke; Suzuki, Kanae; Takanobu, Junko; Gohno, Tatsuyuki; Yamaguchi, Yuri; Hayashi, Shin-Ichi

    2017-01-01

    The relationship between tobacco smoke and breast cancer incidence has been studied for many years, but the effect of smoking on hormonal therapy has not been previously reported. We investigated the effect of smoking on hormonal therapy by performing in vitro experiments. We first prepared tobacco smoke condensate (TSC) and examined its effect on estrogen receptor (ER) activity. The ER activity was analyzed using MCF-7-E10 cells into which the estrogen-responsive element (ERE)-green fluorescent protein (GFP) reporter gene had been stably introduced (GFP assay) and performing an ERE-luciferase assay. TSC significantly activated ERs, and upregulated its endogenous target genes. This activation was inhibited by fulvestrant but more weakly by tamoxifen. These results suggest that the activation mechanism may be different from that for estrogen. Furthermore, using E10 estrogen depletion-resistant cells (EDR cells) established as a hormonal therapy-resistant model showing estrogen-independent ER activity, ER activation and induction of ER target genes were significantly higher following TSC treatment than by estradiol (E2). These responses were much higher than those of the parental E10 cells. In addition, the phosphorylation status of signaling factors (ERK1/2, Akt) and ER in the E10-EDR cells treated with TSC increased. The gene expression profile induced by estrogenic effects of TSC was characterized by microarray analysis. The findings suggested that TSC activates ER by both ligand-dependent and -independent mechanisms. Although TSC constituents will be metabolized in vivo, breast cancer tissues might be exposed for a long period along with hormonal therapy. Tobacco smoke may have a possibility to interfere with hormonal therapy for breast cancer, which may have important implications for the management of therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. [The correlations between polymorphism of growth hormone receptor gene and butcher traits in rabbit].

    Science.gov (United States)

    Deng, Xiao-Song; Wan, Jie; Chen, Shi-Yi; Wang, Yan; Lai, Song-Jia; Jiang, Mei-Shan; Xu, Min

    2008-11-01

    Five rabbit populations (Belgian hare, Tianfu black rabbit, Great line of Zika rabbit, Harbin white rabbit, and California rabbit) were used to analyze the polymorphism of growth hormone receptor (GHR) gene by PCR-SSCP. Results indicated that there were two mutation sites (C705T and C810T) in the 5 populations. The least square analyses showed that the live weight, visceraste weight, and slaughter percentage of AA and MM genotypes were significantly lower than BB and NN genotypes (P0.05). It suggested that GHR gene may be a candidate gene responsible for butcher trait in rabbit.

  4. Synthesis, Receptor Binding, and CNS Pharmacological Studies of New Thyrotropin-Releasing Hormone (TRH) Analogues

    OpenAIRE

    Monga, Vikramdeep; Meena, Chhuttan L.; Rajput, Satyendra; Pawar, Chandrashekhar; Shyam S. Sharma; Lu, Xinping; Gershengorn, Marvin C.; Jain, Rahul

    2011-01-01

    As part of our search for selective and CNS-active thyrotropin-releasing hormone (TRH) analogues, we synthesized a set of 44 new analogues in which His and pGlu residues were modified or replaced. The analogues were evaluated as agonists at TRH-R1 and TRH-R2 in cells in vitro, and in vivo in mice for analeptic and anticonvulsant activities. Several analogues bound to TRH-R1 and TRH-R2 with good to moderate affinities, and are full agonists at both receptor subtypes. Specifically, analogue 21 ...

  5. Neurochemical characterization of neurons expressing melanin-concentrating hormone receptor 1 in the mouse hypothalamus1

    OpenAIRE

    Chee, Melissa J. S.; Pissios, Pavlos; Maratos-Flier, Eleftheria

    2013-01-01

    Melanin-concentrating hormone (MCH) is a hypothalamic neuropeptide that acts via MCH receptor 1 (MCHR1) in the mouse. It promotes positive energy balance thus mice lacking MCH or MCHR1 are lean, hyperactive, and resistant to diet-induced obesity. Identifying the cellular targets of MCH is an important step to understanding the mechanisms underlying MCH actions. We generated the Mchr1-cre mouse that expressed cre recombinase driven by the MCHR1 promoter and crossed it with a tdTomato reporter ...

  6. The Effects of Indomethacin, Furosemide and Prostaglandin F2 alpha on Thyroid Hormone Levels in Rams

    OpenAIRE

    KARAHAN, İzzet; PİRİNÇCİ, İbrahim; ATEŞŞAHİN, Ahmet

    2014-01-01

    This study was carried out to investigate the changes occurring in the levels of serum thyroid hormone in rams given indomethacin, furosemide and PGF2a. In the study, 20 Akkaraman rams, approximately 2 years old were used. Indomethacin (3.0 mg/kg), furosemide (2.0 mg/kg) and PGF2a (0.1 mg/kg) were intramuscularly given to the animals in one dose and repeated for four consecutive days. Blood samples were collected after drug administrations. Free-total thyriiodothyrionine and thyroxine (T3 and...

  7. Cow's milk increases the activities of human nuclear receptors peroxisome proliferator-activated receptors alpha and delta and retinoid X receptor alpha involved in the regulation of energy homeostasis, obesity, and inflammation.

    Science.gov (United States)

    Suhara, W; Koide, H; Okuzawa, T; Hayashi, D; Hashimoto, T; Kojo, H

    2009-09-01

    The nuclear peroxisome proliferator-activated receptors (PPAR) have been shown to play crucial roles in regulating energy homeostasis including lipid and carbohydrate metabolism, inflammatory responses, and cell proliferation, differentiation, and survival. Because PPAR agonists have the potential to prevent or ameliorate diseases such as hyperlipidemia, diabetes, atherosclerosis, and obesity, we have explored new natural agonists for PPAR. For this purpose, cow's milk was tested for agonistic activity toward human PPAR subtypes using a reporter gene assay. Milk increased human PPARalpha activity in a dose-dependent manner with a 3.2-fold increase at 0.5% (vol/vol). It also enhanced human PPARdelta activity in a dose-dependent manner with an 11.5-fold increase at 0.5%. However, it only slightly affected human PPARgamma activity. Ice cream, butter, and yogurt also increased the activities of PPARalpha and PPARdelta, whereas vegetable cream affected activity of PPARdelta but not PPARalpha. Skim milk enhanced the activity of PPAR to a lesser degree than regular milk. Milk and fresh cream increased the activity of human retinoid X receptor (RXR)alpha as well as PPARalpha and PPARdelta, whereas neither affected vitamin D3 receptor, estrogen receptors alpha and beta, or thyroid receptors alpha and beta. Both milk and fresh cream were shown by quantitative real-time PCR to increase the quantity of mRNA for uncoupling protein 2 (UCP2), an energy expenditure gene, in a dose-dependent manner. The increase in UCP2 mRNA was found to be reduced by treatment with PPARdelta-short interfering (si)RNA. This study unambiguously clarified at the cellular level that cow's milk increased the activities of human PPARalpha, PPARdelta, and RXRalpha. The possible role in enhancing the activities of PPARalpha, PPARdelta, and RXRalpha, and the health benefits of cow's milk were discussed.

  8. Tumor necrosis factor-alpha induces activation of coagulation and fibrinolysis in baboons through an exclusive effect on the p55 receptor

    NARCIS (Netherlands)

    van der Poll, T.; Jansen, P. M.; van Zee, K. J.; Welborn, M. B.; de Jong, I.; Hack, C. E.; Loetscher, H.; Lesslauer, W.; Lowry, S. F.; Moldawer, L. L.

    1996-01-01

    Tumor necrosis factor-alpha (TNF-alpha) can bind to two distinct transmembrane receptors, the p55 and p75 TNF receptors. We compared the capability of two mutant TNF proteins with exclusive affinity for the p55 or p75 TNF receptor with that of wild type TNF, to activate the hemostatic mechanism in

  9. Growth hormone is protective against acute methadone-induced toxicity by modulating the NMDA receptor complex.

    Science.gov (United States)

    Nylander, Erik; Grönbladh, Alfhild; Zelleroth, Sofia; Diwakarla, Shanti; Nyberg, Fred; Hallberg, Mathias

    2016-12-17

    Human growth hormone (GH) displays promising protective effects in the central nervous system after damage caused by various insults. Current evidence suggests that these effects may involve N-methyl-d-aspartate (NMDA) receptor function, a receptor that also is believed to play a role in opioid-induced neurotoxicity. The aims of the present study were to examine the acute toxic effects of methadone, an opioid receptor agonist and NMDA receptor antagonist, as well as to evaluate the protective properties of recombinant human GH (rhGH) on methadone-induced toxicity. Primary cortical cell cultures from embryonic day 17 rats were grown for 7days in vitro. Cells were treated with methadone for 24h and the 50% lethal dose was calculated and later used for protection studies with rhGH. Cellular toxicity was determined by measuring mitochondrial activity, lactate dehydrogenase release, and caspase activation. Furthermore, the mRNA expression levels of NMDA receptor subunits were investigated following methadone and rhGH treatment using quantitative PCR (qPCR) analysis. A significant protective effect was observed with rhGH treatment on methadone-induced mitochondrial dysfunction and in methadone-induced LDH release. Furthermore, methadone significantly increased caspase-3 and -7 activation but rhGH was unable to inhibit this effect. The mRNA expression of the NMDA receptor subunit GluN1, GluN2a, and GluN2b increased following methadone treatment, as assessed by qPCR, and rhGH treatment effectively normalized this expression to control levels. We have demonstrated that rhGH can rescue cells from methadone-induced toxicity by maintaining mitochondrial function, cellular integrity, and NMDA receptor complex expression. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. Muscarinic and alpha 1-adrenergic receptor binding characteristics of saw palmetto extract in rat lower urinary tract.

    Science.gov (United States)

    Suzuki, Mayumi; Oki, Tomomi; Sugiyama, Tomomi; Umegaki, Keizo; Uchida, Shinya; Yamada, Shizuo

    2007-06-01

    To elucidate the in vitro and ex vivo effects of saw palmetto extract (SPE) on autonomic receptors in the rat lower urinary tract. The in vitro binding affinities for alpha 1-adrenergic, muscarinic, and purinergic receptors in the rat prostate and bladder were measured by radioligand binding assays. Rats received vehicle or SPE (0.6 to 60 mg/kg/day) orally for 4 weeks, and alpha 1-adrenergic and muscarinic receptor binding in tissues of these rats were measured. Saw palmetto extract inhibited specific binding of [3H]prazosin and [N-methyl-3H]scopolamine methyl chloride (NMS) but not alpha, beta-methylene adenosine triphosphate [2,8-(3)H]tetrasodium salt in the rat prostate and bladder. The binding activity of SPE for muscarinic receptors was four times greater than that for alpha 1-adrenergic receptors. Scatchard analysis revealed that SPE significantly reduced the maximal number of binding sites (Bmax) for each radioligand in the prostate and bladder under in vitro condition. Repeated oral administration of SPE to rats brought about significant alteration in Bmax for prostatic [3H]prazosin binding and for bladder [3H]NMS binding. Such alteration by SPE was selective to the receptors in the lower urinary tract. Saw palmetto extract exerts significant binding activity on autonomic receptors in the lower urinary tract under in vitro and in vivo conditions.

  11. Silencing Mediator of Retinoid and Thyroid Hormone Receptors (SMRT) regulates glucocorticoid action in adipocytes.

    Science.gov (United States)

    Emont, Margo P; Mantis, Stelios; Kahn, Jonathan H; Landeche, Michael; Han, Xuan; Sargis, Robert M; Cohen, Ronald N

    2015-05-15

    Local modulation of glucocorticoid action in adipocytes regulates adiposity and systemic insulin sensitivity. However, the specific cofactors that mediate glucocorticoid receptor (GR) action in adipocytes remain unclear. Here we show that the silencing mediator of retinoid and thyroid hormone receptors (SMRT) is recruited to GR in adipocytes and regulates ligand-dependent GR function. Decreased SMRT expression in adipocytes in vivo increases expression of glucocorticoid-responsive genes. Moreover, adipocytes with decreased SMRT expression exhibit altered glucocorticoid regulation of lipolysis. We conclude that SMRT regulates the metabolic functions of GR in adipocytes in vivo. Modulation of GR-SMRT interactions in adipocytes represents a novel approach to control the local degree of glucocorticoid action and thus influence adipocyte metabolic function. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. Evolution of parathyroid hormone receptor family and their ligands in vertebrate

    Directory of Open Access Journals (Sweden)

    Jason S.W. eOn

    2015-03-01

    Full Text Available The presence of the parathyroid hormones in vertebrates, including PTH, PTH-related peptide (PTHrP and tuberoinfundibular peptide of 39 residues (TIP39, has been proposed to be the result of two rounds of whole genome duplication in the beginning of vertebrate diversification. Bioinformatics analyses, in particular chromosomal synteny study and the characterization of the PTH ligands and their receptors from various vertebrate species, provide evidence that strongly supports this hypothesis. In this mini-review, we summarize recent advances in studies regarding the molecular evolution and physiology of the PTH ligands and their receptors, with particular focus on non-mammalian vertebrates. In summary, the PTH family of peptides probably predates early vertebrate evolution, indicating a more ancient existence as well as a function of these peptides in invertebrates.

  13. Negative regulation of parathyroid hormone-related protein expression by steroid hormones

    Energy Technology Data Exchange (ETDEWEB)

    Kajitani, Takashi; Tamamori-Adachi, Mimi [Department of Biochemistry, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605 (Japan); Okinaga, Hiroko [Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605 (Japan); Chikamori, Minoru; Iizuka, Masayoshi [Department of Biochemistry, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605 (Japan); Okazaki, Tomoki, E-mail: okbgeni@med.teikyo-u.ac.jp [Department of Biochemistry, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605 (Japan)

    2011-04-15

    Highlights: {yields} Steroid hormones repress expression of PTHrP in the cell lines where the corresponding nuclear receptors are expressed. {yields} Nuclear receptors are required for suppression of PTHrP expression by steroid hormones, except for androgen receptor. {yields} Androgen-induced suppression of PTHrP expression appears to be mediated by estrogen receptor. -- Abstract: Elevated parathyroid hormone-related protein (PTHrP) is responsible for humoral hypercalcemia of malignancy (HHM), which is of clinical significance in treatment of terminal patients with malignancies. Steroid hormones were known to cause suppression of PTHrP expression. However, detailed studies linking multiple steroid hormones to PTHrP expression are lacking. Here we studied PTHrP expression in response to steroid hormones in four cell lines with excessive PTHrP production. Our study established that steroid hormones negatively regulate PTHrP expression. Vitamin D receptor, estrogen receptor {alpha}, glucocorticoid receptor, and progesterone receptor, were required for repression of PTHrP expression by the cognate ligands. A notable exception was the androgen receptor, which was dispensable for suppression of PTHrP expression in androgen-treated cells. We propose a pathway(s) involving nuclear receptors to suppress PTHrP expression.

  14. Synthesis of the 7alpha-cyano-(17alpha,20E/Z)-[125I]iodovinyl-19-nortestosterones: potential radioligands for androgen and progesterone receptors.

    Science.gov (United States)

    Ali, Hasrat; Rousseau, Jacques; Ahmed, Naseem; Guertin, Veronique; Hochberg, Richard B; van Lier, Johan E

    2003-12-01

    We report the preparation of the 7alpha-cyano derivative of the isomeric (17alpha,20E/Z)-[125I]iodovinyl-19-nortestosterones (IVNT) together with their binding affinity for the androgen receptor (AR) and their biodistribution in two different animal models. The cyano group was introduced at the 7alpha-position by hydrocyanation of 4,6-estradien-17beta-ol-3-one with diethylaluminum cyanide. Selective protection of the A-ring enone system as the dienol ether followed by ethynylation and deprotection under base and acid hydrolysis condition gave 7alpha-cyano-17alpha-ethynyl-19-nortestosterone. The stannyl derivatives were prepared by addition of tri-n-butylstannyl hydride and converted stereospecifically to the corresponding [125I]iodovinyl analog using [125I]NaI and H2O2. The [125I]iodovinylsteroids were intravenously administered to male rats and estrogen-primed immature female rats and tissue uptake was measured up to 6h post-injection. Co-administration of NLP-004 or ORG-2058, highly selective ligands for the progesterone receptor, to the female rats did not affect uterus uptake of the 125I-ligands. However co-injection of testosterone to DES-primed male rats induced a marked increase in prostate uptake of the 20Z-isomer of 7alpha-cyano-[125I]-IVNT. The relative binding affinity (RBA) of either 7alpha-cyano-(17alpha,20E/Z)-IVNT isomer for the AR is low (RBA=4 and 3, respectively, versus 100 for 5alpha-dihydrotestosterone (DHT)), suggesting the absence of a possible role of the AR in the localization process. These findings contrast previously reported data for the analogous 7alpha-methyl-[125I]-IVNT where co-administration of testosterone was shown to result in a 50% drop in prostate uptake. These data indicate that the addition of an electron withdrawing 7alpha-cyano group to 123I-labeled nortestosterone derivatives does not improve their potential to serve as SPECT agents for the imaging of AR densities in the prostate.

  15. Effects of alpha-7 nicotinic acetylcholine receptor positive allosteric modulator on lipopolysaccharide-induced neuroinflammatory pain in mice.

    Science.gov (United States)

    Abbas, Muzaffar; Rahman, Shafiqur

    2016-07-15

    Evidence indicates that microglial activation contributes to the pathophysiology and maintenance of neuroinflammatory pain involving central nervous system alpha-7 nicotinic acetylcholine receptors. The objective of the present study was to determine the effects of 3a,4,5,9b-Tetrahydro-4-(1-naphthalenyl)-3H-cyclopentan[c]quinoline-8-sulfonamide (TQS), an alpha-7 nicotinic acetylcholine receptor positive allosteric modulator (PAM), on tactile allodynia and thermal hyperalgesia following lipopolysaccharide (LPS)-induced microglial activation in hippocampus, a neuroinflammatory pain model in mice. In addition, we examined the effects of TQS on microglial activation marker, an ionized calcium-binding adapter molecule 1 (Iba-1), in the hippocampus may be associated with neuroinflammatory pain. Pretreatment of TQS (4mg/kg) significantly reduced LPS (1mg/kg)-induced tactile allodynia and thermal hyperalgesia. Moreover, pretreatment of methyllycaconitine (3mg/kg) significantly reversed TQS-induced antiallodynic and antihyperalgesic responses indicating the involvement of alpha-7 nicotinic acetylcholine receptor. Pretreatment of TQS significantly decreased LPS-induced increased in hippocampal Iba-1 expression. Overall, these results suggest that TQS reduces LPS-induced neuroinflammatory pain like symptoms via modulating microglial activation likely in the hippocampus and/or other brain region by targeting alpha-7 nicotinic acetylcholine receptor. Therefore, alpha-7 nicotinic acetylcholine receptor PAM such as TQS could be a potential drug candidate for the treatment of neuroinflammatory pain. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Chicken epidermal growth factor (EGF) receptor: cDNA cloning, expression in mouse cells, and differential binding of EGF and transforming growth factor alpha

    DEFF Research Database (Denmark)

    Lax, I; Johnson, A; Howk, R

    1988-01-01

    receptor molecule. Surprisingly, human transforming growth factor alpha (TGF-alpha) bound equally well or even better to the chicken EGF receptor than to the human EGF receptor. Moreover, TGF-alpha stimulated DNA synthesis 100-fold better than did EGF in NIH 3T3 cells that expressed the chicken EGF......The primary structure of the chicken epidermal growth factor (EGF) receptor was deduced from the sequence of a cDNA clone containing the complete coding sequence and shown to be highly homologous to the human EGF receptor. NIH-3T3 cells devoid of endogenous EGF receptor were transfected...... receptor. The differential binding and potency of mammalian EGF and TGF-alpha by the avian EGF receptor contrasts with the similar affinities of the mammalian receptor for the two growth factors....

  17. Affinity chromatography of alpha/sub 2/-adrenergic receptors (. cap alpha. /sub 2/AR) from pig cerebral cortex

    Energy Technology Data Exchange (ETDEWEB)

    Repaske, M.G.; Limbird, L.E.

    1986-03-01

    A high capacity, ..cap alpha../sub 2/AR-selective affinity resin (YOH. ag) has been prepared by coupling yohimbinic acid to diaminodipropylamine agarose with 1,3 dicyclohexylcarbodiimide. Unreacted amino groups on the agarose matrix are blocked subsequently by acetylation. One volume of YOH. ag adsorbs 75% of the ..cap alpha../sub 2/AR from 50 volumes of digitonin-solubilized preparation containing 0.2 pmol ..cap alpha../sub 2/AR/mg protein. Digitonin-solubilized preparations are derived from cholate extracts of porcine cerebral cortex containing approx. 0.075 pmol ..cap alpha../sub 2/AR/mg protein. Adsorption of ..cap alpha../sub 2/AR to YOH. ag is selective and thus is blocked by the ..cap alpha..-adrenergic antagonist phentolamine. Adsorbed ..cap alpha../sub 2/AR are eluted with 10 ..mu..M phentolamine (20% yield) after removal of non-related proteins with NaCl gradients. Following hydroxylapatite chromatography to concentrate ..cap alpha..''AR and to remove phentolamine, the ..cap alpha..AR is present at 200-400 pmol/mg protein, assayed using sub-saturating concentrations of (/sup 3/H)-yohimbine. (It is estimated that the specific activity of a homogeneous ..cap alpha../sub 2/AR preparation would be 12,000-16,000 pmol/mg protein.) The availability of large quantities of cortical ..cap alpha../sub 2/AR and a resin easily prepared from commercially-supplied reagents suggests that purification of quantities of ..cap alpha../sub 2/AR sufficient for subsequent biochemical studies is feasible.

  18. Photoperiod affects estrogen receptor alpha, estrogen receptor beta and aggressive behavior.

    Science.gov (United States)

    Trainor, Brian C; Rowland, Michael R; Nelson, Randy J

    2007-07-01

    Estrogens have important effects on male and female social behavior. Despite growing knowledge of the anatomy and behavioral effects of the two predominant estrogen receptor subtypes in mammals (ERalpha and ERbeta), relatively little is known about how these receptors respond to salient environmental stimuli. Many seasonally breeding species respond to changing photoperiods that predict seasonal changes in resource availability. We characterized the effects of photoperiod on aggressive behavior in two species of Peromyscus that exhibit gonadal regression in short days. P. polionotus (old field mice) were more aggressive than P. maniculatus (deer mice) and both species were more aggressive in short days. We used immunocytochemistry and real-time polymerase chain reaction to characterize the effects of photoperiod on ERalpha and ERbeta expression. In both species ERalpha-immunoreactive staining in the posterior bed nucleus of the stria terminalis (BNST) was increased in short vs. long days. Both species had reduced ERbeta-immunoreactive expression in the posterior BNST in short days. In the medial amygdala ERbeta immunoreactivity was increased in long days for both species. Using real-time polymerase chain reaction on punch samples that included the BNST, we observed that ERalpha mRNA was increased and ERbeta mRNA was decreased in short days. These data suggest that the effects of photoperiod on ERalpha and ERbeta expression may thus have important behavioral consequences.

  19. Distribution of thyroid hormone and thyrotropin receptors in reproductive tissues of adult female rabbits.

    Science.gov (United States)

    Rodríguez-Castelán, Julia; Anaya-Hernández, Arely; Méndez-Tepepa, Maribel; Martínez-Gómez, Margarita; Castelán, Francisco; Cuevas-Romero, Estela

    2017-02-01

    Thyroid dysfunctions are related to anovulation, miscarriages, and infertility in women and laboratory animals. Mechanisms associated with these effects are unknown, although indirect or direct actions of thyroid hormones and thyrotropin could be assumed. The present study aimed to identify the distribution of thyroid hormones (TRs) and thyrotropin (TSHR) receptors in reproductive organs of female rabbits. Ovary of virgin and pregnant rabbits, as well as the oviduct, uterus, and vagina of virgin rabbits were excised, histologically processed, and cut. Slices from these organs were used for immunohistochemical studies for TRα1-2, TRß1, and TSHR. The presence of TRs and TSHR was found in the primordial, primary, secondary, tertiary, and Graafian follicles of virgin rabbits, as well as in the corpora lutea, corpora albicans, and wall of hemorrhagic cysts of pregnant rabbits. Oviductal regions (fimbria-infundibulum, ampulla, isthmus, and utero-tubal junction), uterus (endometrium and myometrium), and vagina (abdominal, pelvic, and perineal portions) of virgin rabbits showed anti-TRs and anti-TSHR immunoreactivity. Additionally, the distal urethra, paravaginal ganglia, levator ani and iliococcygeus muscles, dorsal nerve and body of the clitoris, perigenital skin, and prostate had TRs and TSHR. The wide presence of TRs and TSHR in female reproductive organs suggests varied effects of thyroid hormones and thyrotropin in reproduction.

  20. Tumor necrosis factor-alpha and its receptors in epithelial ovarian cancer.

    Directory of Open Access Journals (Sweden)

    Jacek Nikliński

    2010-05-01

    Full Text Available The aim of the present study was to characterize the expression pattern of tumor necrosis factor (TNF-alpha and its receptors (TNF-Rs in the epithelial ovarian cancer (EOC and compare these results with the outcome of 126 patients. Presence of TNF-alpha, TNFR-1 and TNFR-2 were studied by Western blotting and immunohistochemistry. The proportion of samples positive for TNF-alpha and TNF-R2 was higher in epithelial ovarian cancer patients than in benign ovarian diseases (p<0.001 and p=0.016, respectively. Immunostaining intensity of TNF-R2 were correlated with tumor stage (p<0.001 and with reduced mean survival time (MST (p=0.002. The results of the present study suggested that tissue expression of TNF-R2 in epithelial ovarian cancer was correlated with the highest risk of cancer progression. Thus, the clinical value of activated TNF system in epithelial ovarian cancer needs to be further investigated.

  1. Evidence that the newly cloned low-density-lipoprotein receptor related protein (LRP) is the alpha 2-macroglobulin receptor

    DEFF Research Database (Denmark)

    Kristensen, T; Moestrup, Søren Kragh; Gliemann, Jørgen

    1990-01-01

    these polypeptides, and analysis of a 1772 bp cDNA encoding part of the 500 kDa polypeptide provide evidence that the 500 kDa and 85 kDa chains are the alpha- and beta-subunits, respectively, of a recently cloned hepatic membrane protein, termed the low density lipoprotein receptor related protein (LRP) (Herz, J......., Hamann, U., Rogne, S., Myklebost, O., Gausepohl, H. and Stanley, K.K. (1988) EMBO J. 7, 4119-4127; Herz, J., Kowal, R.C., Goldstein, J.L. and Brown, M.S. (1990) EMBO J. 9, 1769-1776). N-terminal sequence analysis of the 40 kDa polypeptide shows that it is of distinct genetic origin. It is suggested...

  2. Autoantibodies to folate receptor alpha during early pregnancy and risk of oral clefts in Denmark

    DEFF Research Database (Denmark)

    Bille, Camilla; Pedersen, Dorthe Almind; Andersen, Anne-Marie Nybo

    2010-01-01

    The objective of this study was to determine whether IgG and IgM autoantibodies to folate receptor alpha (FRalpha) in pregnant women are associated with an increased risk of oral cleft-affected offspring. A case-control study nested in the prospective Danish National Birth Cohort (100,418 pregnan...... in maternal serum during pregnancy are not associated with an increased risk of oral clefts in the offspring in this population-based cohort.......The objective of this study was to determine whether IgG and IgM autoantibodies to folate receptor alpha (FRalpha) in pregnant women are associated with an increased risk of oral cleft-affected offspring. A case-control study nested in the prospective Danish National Birth Cohort (100......,418 pregnancies, enrolled during 1997-2003) was done. Hundred eighty-five children were born with an oral cleft. Maternal serum from their mothers (cases) was compared with maternal serum from 779 randomly selected mothers of nonmalformed children (controls). We found that the average level of FRalpha Ig...

  3. Expression of urocortin and corticotropin-releasing hormone receptors in the horse thyroid gland.

    Science.gov (United States)

    Squillacioti, Caterina; De Luca, Adriana; Alì, Sabrina; Paino, Salvatore; Liguori, Giovanna; Mirabella, Nicola

    2012-10-01

    Urocortin (UCN) is a 40-amino-acid peptide and a member of the corticotropin-releasing hormone (CRH) family, which includes CRH, urotensin I, sauvagine, UCN2 and UCN3. The biological actions of CRH family peptides are mediated via two types of G-protein-coupled receptors, namely CRH type 1 receptor (CRHR1) and CRH type 2 receptor (CRHR2). The biological effects of these peptides are mediated and modulated not only by CRH receptors but also via a highly conserved CRH-binding protein (CRHBP). Our aim was to investigate the expression of UCN, CRHR1, CRHR2 and CRHBP by immunohistochemistry, Western blot and reverse transcription with the polymerase chain reaction (RT-PCR) in the horse thyroid gland. The results showed that UCN, CRHR1 and CRHR2 were expressed in the thyroid gland, whereas CRHBP was not expressed. Specifically, UCN immunoreactivity (-IR) was found in the thyroid follicular cells, CRHR2-IR in the C-cells and CRHR1-IR in blood vessels. Western blot analysis and RT-PCR experiments confirmed the immunohistochemical data. These results suggest that a regulatory system exists in the mammalian thyroid gland based on UCN, CRHR1 and CRHR2 and that UCN plays a role in the regulation of thyroid physiological functions through a paracrine mechanism.

  4. Proliferation of Estrogen Receptor alpha Positive Mammary Epithelial Cells is Restrained by TGFbeta1 in Adult Mice

    Energy Technology Data Exchange (ETDEWEB)

    Ewan, Kenneth B.R.; Oketch-Rabah, Hellen A.; Ravani, Shraddha A.; Shyamala, G.; Moses, Harold L.; Barcellos-Hoff, Mary Helen

    2005-03-03

    Transforming growth factor {beta}1 (TGF{beta}1) is a potent inhibitor of mammary epithelial proliferation. In human breast, estrogen receptor {alpha} (ER{alpha}) cells rarely co-localize with markers of proliferation, but their increased frequency correlates with breast cancer risk. To determine whether TGF{beta}1 is necessary for the quiescence of ER{alpha}-positive population, we examined mouse mammary epithelial gland at estrus. Approximately 35% of cells showed TGF{beta}1 activation, which co-localized with nuclear receptor-phosphorylated Smad 2/3, indicating that TGF{beta} signaling is autocrine. Furthermore, nuclear Smad co-localized with nuclear ER{alpha}. To test whether TGF{beta} was functional, we examined genetically engineered mice with different levels of TGF{beta}1. ER{alpha} co-localization with markers of proliferation (i.e. Ki-67 or BrdU) at estrus was significantly increased in the mammary glands of Tgf{beta}1 C57/bl/129SV heterozygote mice. This relationship was maintained following pregnancy, but was absent at puberty. Conversely, mammary epithelial expression of constitutively active TGF{beta}1 via the MMTV promoter suppressed proliferation of ER{alpha} positive cells. Thus, TGF{beta}1 activation functionally restrains ER{alpha} positive cells from proliferating in adult mammary gland. Accordingly, we propose that TGF{beta}1 dysregulation may promote proliferation of ER{alpha} positive cells associated with breast cancer risk in humans.

  5. UTX promotes hormonally responsive breast carcinogenesis through feed-forward transcription regulation with estrogen receptor.

    Science.gov (United States)

    Xie, G; Liu, X; Zhang, Y; Li, W; Liu, S; Chen, Z; Xu, B; Yang, J; He, L; Zhang, Z; Jin, T; Yi, X; Sun, L; Shang, Y; Liang, J

    2017-09-28

    UTX is implicated in embryonic development and lineage specification. However, how this X-linked histone demethylase contributes to the occurrence and progression of breast cancer remains to be clarified. Here we report that UTX is physically associated with estrogen receptor (ER) and functions in ER-regulated transcription. We showed that UTX coordinates with JHDM1D and CBP to direct H3K27 methylation-acetylation transition and to create a permissive chromatin state on ER targets. Genome-wide analysis of the transcriptional targets of UTX by ChIP-seq identified a set of genes such as chemokine receptor CXCR4 that are intimately involved in breast cancer tumorigenesis and metastasis. We demonstrated that UTX promotes the proliferation and migration of ER(+) breast cancer cells. Interestingly, UTX itself is transactivated by ER, forming a feed-forward loop in the regulation of hormone response. Indeed, UTX is upregulated during ER(+) breast cancer progression, and the expression level of UTX is positively correlated with that of CXCR4 and negatively correlated with the overall survival of ER(+) breast cancer patients. Our study identified a feed-forward loop between UTX and ER in the regulation of hormonally responsive breast carcinogenesis, supporting the pursuit of UTX as an emerging therapeutic target for the intervention of certain ER(+) breast cancer with specific epigenetic vulnerability.

  6. Ovarian hormones modify anxiety behavior and glucocorticoid receptors after chronic social isolation stress.

    Science.gov (United States)

    Ramos-Ortolaza, Dinah L; Doreste-Mendez, Raura J; Alvarado-Torres, John K; Torres-Reveron, Annelyn

    2017-06-15

    Chronic social isolation could lead to a disruption in the Hypothalamic-Pituitary-Adrenal (HPA) axis, resulting in anxiety and depressive-like behaviors but cycling estrogens could modify these behaviors. The aim of this study was to determine if changes in ovarian hormones during the normal cycle could interact with social isolation to alter anxiety and depressive-like behaviors. In parallel, we examined the expression of glucocorticoid receptor (GR) and synaptic vesicle protein synaptophysin in the hippocampus and hypothalamus of Sprague Dawley normal cycling female rats. We assigned rats to either isolated or paired housing for 8 weeks. To assess anxiety and depressive-like behaviors, we used the open field test and forced swim test, respectively. Female rats were tested at either diestrus, estrus, or proestrus stage of the estrous cycle. After behaviors, rats were perfused and brains collected. Brain sections containing hippocampus and hypothalamus were analyzed using immunohistochemistry for synaptophysin and glucocorticoid receptor (GR) levels. We found an increase in depressive-like behaviors for isolated animals compared to paired housed rats, regardless of the estrous cycle stage. Interestingly, we found a decrease in anxiety behaviors in females in the estrus stage accompanied by a decrease in GR expression in hippocampal DG and CA3. However, no changes in synaptophysin were observed in any of the areas of studied. Our results support the beneficial effects of circulating ovarian hormones in anxiety, possibly by decreasing GR expression. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Withdrawal from 3alpha-OH-5alpha-pregnan-20-One using a pseudopregnancy model alters the kinetics of hippocampal GABAA-gated current and increases the GABAA receptor alpha4 subunit in association with increased anxiety.

    Science.gov (United States)

    Smith, S S; Gong, Q H; Li, X; Moran, M H; Bitran, D; Frye, C A; Hsu, F C

    1998-07-15

    In the present study, we have characterized properties of steroid withdrawal using a pseudopregnant rat model. This paradigm results in increased production of endogenous progesterone from ovarian sources and as such is a useful physiological model. "Withdrawal" from progesterone induced by ovariectomy on day 12 of pseudopregnancy resulted in increased anxiety, as determined by a decrease in open arm entries on the elevated plus maze compared to control rats and pseudopregnant animals not undergoing withdrawal. Similar findings were obtained 24 hr after administration of a 5alpha-reductase blocker to a pseudopregnant animal, suggesting that it is the GABAA-modulatory 3alpha-OH-5alpha-pregnan-20-one (3alpha, 5alpha-THP) that produces anxiogenic withdrawal symptoms. Twenty-four hours after steroid withdrawal, the time constant for decay of GABAA-gated current was also reduced sixfold, assessed using whole- cell patch-clamp procedures on pyramidal neurons acutely dissociated from CA1 hippocampus. Thus, 3alpha,5alpha-THP withdrawal results in a marked decrease in total GABAA current, a possible mechanism for its anxiogenic, proconvulsant sequelae. In addition, 3alpha,5alpha-THP withdrawal resulted in insensitivity to the normally potentiating effect of the benzodiazepine lorazepam (LZM) on GABAA-gated Cl- current. This withdrawal profile is similar to that reported for other GABAA-modulatory drugs such as the benzodiazepines (BDZs), barbiturates, and ethanol. These changes were also associated with significant two and threefold increases in both the mRNA and protein for the alpha4 subunit of the GABAA receptor, respectively, in hippocampus. The pseudopregnancy paradigm may be a useful model for periods of endogenous 3alpha,5alpha-THP withdrawal such as premenstrual syndrome and postpartum or postmenopausal dysphoria, when increased emotional lability and BDZ insensitivity have been reported.

  8. Gonadotropin-releasing hormone and gonadotropin-releasing hormone receptor are expressed at tubal ectopic pregnancy implantation sites.

    Science.gov (United States)

    Peng, Bo; Klausen, Christian; Campbell, Lisa; Leung, Peter C K; Horne, Andrew W; Bedaiwy, Mohamed A

    2016-06-01

    To investigate whether gonadotropin-releasing hormone (GnRH) and GnRH receptor (GnRHR) are expressed at tubal ectopic pregnancy sites, and to study the potential role of GnRH signaling in regulating immortalized human trophoblast cell viability. Immunohistochemical and experimental studies. Academic research laboratory. Fallopian tube implantation sites (n = 25) were collected from women with ectopic pregnancy. First-trimester human placenta biopsies (n = 5) were obtained from elective terminations of pregnancy. None. GnRH and GnRHR expression was examined by means of immunohistochemistry and histoscoring. Trophoblastic BeWo choriocarcinoma and immortalized extravillous trophoblast (HTR-8/SVneo) cell viability was examined by means of cell counting after incubation with GnRH and/or GnRH antagonist (Antide). GnRH and GnRHR immunoreactivity was detected in cytotrophoblast, syncytiotrophoblast, and extravillous trophoblast in all women with tubal pregnancy. GnRH immunoreactivity was higher and GnRHR immunoreactivity lower in syncytiotrophoblast compared with cytotrophoblast. GnRH and GnRHR immunoreactivity was detected in adjacent fallopian tube epithelium. Whereas neither GnRH nor Antide altered HTR-8/SVneo cell viability, treatment with GnRH significantly increased the overall cell viability of BeWo cells at 48 and 72 hours, and these effects were abolished by pretreatment with Antide. GnRH and GnRHR are expressed in trophoblast cell populations and fallopian tube epithelium at tubal ectopic pregnancy sites. GnRH increases BeWo cell viability, an effect mediated by the GnRHR. Further work is required to investigate the potential role of GnRH signaling in ectopic pregnancy. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  9. Cellular expression of growth hormone and prolactin receptors in human breast disorders.

    Science.gov (United States)

    Mertani, H C; Garcia-Caballero, T; Lambert, A; Gérard, F; Palayer, C; Boutin, J M; Vonderhaar, B K; Waters, M J; Lobie, P E; Morel, G

    1998-04-17

    Growth hormone (GH) and prolactin (PRL) exert their regulatory functions in the mammary gland by acting on specific receptors. Using isotopic in situ hybridization and immunohistochemistry, we have localized the expression of hGH receptor (hGHR) and hPRL receptor (hPRLR) in a panel of human breast disorders. Surgical specimens from adult females included normal breast, inflammatory lesions (mastitis) benign proliferative breast disease (fibroadenoma, papilloma, adenosis, epitheliosis), intraductal carcinoma or lobular carcinoma in situ, and invasive ductal, lobular or medullary carcinoma. Cases of male breast enlargement (gynecomastia) were also studied. In situ hybridization analysis demonstrated the co-expression of hGHR and hPRLR mRNA in all samples tested. Epithelial cells of both normal and tumor tissues were labelled. Quantitative estimation of receptor mRNA levels was regionally measured in areas corresponding to tumor cells and adipose cells from the same section. It demonstrated large individual variation and no correlation emerged according to the histological type of lesion. Receptor immunoreactivity was detected both in the cytoplasm and nuclei or in the cytoplasm alone. Scattered stromal cells were found positive in some cases, but the labeling intensity was always weaker than for neoplastic epithelial cells. Our results demonstrate the expression of the hGHR and hPRLR genes and their translation in epithelial cells of normal, proliferative and neoplastic lesions of the breast. They also demonstrate that stromal components express GHR and PRLR genes. Thus the putative role of hGH or hPRL in the progression of proliferative mammary disorders is not due to grossly altered levels of receptor expression.

  10. Interaction of alpha-conotoxin ImII and its analogs with nicotinic receptors and acetylcholine-binding proteins: additional binding sites on Torpedo receptor.

    Science.gov (United States)

    Kasheverov, Igor E; Zhmak, Maxim N; Fish, Alexander; Rucktooa, Prakash; Khruschov, Alexey Yu; Osipov, Alexey V; Ziganshin, Rustam H; D'hoedt, Dieter; Bertrand, Daniel; Sixma, Titia K; Smit, August B; Tsetlin, Victor I

    2009-11-01

    alpha-Conotoxins interact with nicotinic acetylcholine receptors (nAChRs) and acetylcholine-binding proteins (AChBPs) at the sites for agonists/competitive antagonists. alpha-Conotoxins blocking muscle-type or alpha7 nAChRs compete with alpha-bungarotoxin. However, alpha-conotoxin ImII, a close homolog of the alpha7 nAChR-targeting alpha-conotoxin ImI, blocked alpha7 and muscle nAChRs without displacing alpha-bungarotoxin (Ellison et al. 2003, 2004), suggesting binding at a different site. We synthesized alpha-conotoxin ImII, its ribbon isomer (ImIIiso), 'mutant' ImII(W10Y) and found similar potencies in blocking human alpha7 and muscle nAChRs in Xenopus oocytes. Both isomers displaced [(125)I]-alpha-bungarotoxin from human alpha7 nAChRs in the cell line GH(4)C(1) (IC(50) 17 and 23 microM, respectively) and from Lymnaea stagnalis and Aplysia californica AChBPs (IC(50) 2.0-9.0 microM). According to SPR measurements, both isomers bound to immobilized AChBPs and competed with AChBP for immobilized alpha-bungarotoxin (K(d) and IC(50) 2.5-8.2 microM). On Torpedo nAChR, alpha-conotoxin [(125)I]-ImII(W10Y) revealed specific binding (K(d) 1.5-6.1 microM) and could be displaced by alpha-conotoxin ImII, ImIIiso and ImII(W10Y) with IC(50) 2.7, 2.2 and 3.1 microM, respectively. As alpha-cobratoxin and alpha-conotoxin ImI displaced [(125)I]-ImII(W10Y) only at higher concentrations (IC(50)> or = 90 microM), our results indicate that alpha-conotoxin ImII and its congeners have an additional binding site on Torpedo nAChR distinct from the site for agonists/competitive antagonists.

  11. Binding of alpha-bungarotoxin to chick sympathetic ganglia: properties of the receptor and its rate of appearance during developement.

    Science.gov (United States)

    Greene, L A

    1976-07-23

    Studies were carried out on the binding of [125I]alpha-bungarotoxin (alphaBT) to membrane fragments of chick sympathetic ganglia. Specific binding of toxin was saturable with a KD of 1.1 nM. The rates of association and dissociation of the toxin from ganglionic membranes were 4.3 X 10(4) M-1 sec-1 and 4.6 X 10(-5) sec-1 (t 1/2 = 4.2 h). respectively. Binding was inhibited (by up to 95%) by low concentrations of nicotinic, but not by a muscarinic cholinergic ligand. The properties of the ganglionic binding site for alphaBT were consistent with its being a nicotinic acetylcholine receptor. The development of toxin receptors in chick ganglia was also studied. From days 7 to 11 in ovo, few receptors were present; from days 12 to 20 in ovo, there was a 10-fold increase in receptor number per ganglion; from hatching to maturity, the receptor number per ganglion slowly increased and reached a maximum of 14 fmoles. The ontogeny of receptors for alphaBT in sympathetic ganglia appears to correlate with the cytological maturation and innervation of the principal neurons.

  12. Transcriptomic signatures of peroxisome proliferator-activated receptor alpha (PPARalpha) in different mouse liver models identify novel aspects of its biology

    National Research Council Canada - National Science Library

    Szalowska, E; Tesfay, H.A; Hijum, S.A.F.T. van; Kersten, S

    2014-01-01

    BACKGROUND: The peroxisome proliferator-activated receptor alpha (PPARalpha) is a ligand-activated transcription factor that regulates lipid catabolism and inflammation and is hepatocarcinogenic in rodents...

  13. Fluorescence Techniques for Measuring Kinetics of Specific Binding of Hormone to Cell Surface Receptors.

    Science.gov (United States)

    Hellen, Edward Herbert

    This thesis presents theoretical calculations and technical advances relevant to total internal reflection/ fluorescence photobleaching recovery (tir/fpr), and results from experiments using tir/fpr to measure the dissociation rate constant of epidermal growth factor (egf) hormone interacting with its receptor molecule on A431 cells. The classical electromagnetic calculations describe fluorescence emission from fluorophores near an interface (possibly metal coated). It is well known that an interface alters the emission properties of nearby fluorophores. Most previous classical calculations model the fluorophore as a fixed-amplitude dipole oscillator. However, for fluorophores under steady illumination, a fixed-power dipole is more appropriate. This modification corresponds to normalizing the fixed-amplitude dipole's intensity by its total dissipated power. The results for the fixed-power model differ nontrivially from the fixed-amplitude model. The observation-angle -dependent intensity as a function of the fluorophore's orientation and distance from the surface is calculated. General expressions are derived for the emission power as observed through a circular-aperture collection system located on either side of the interface. A system for maintaining long-term focus of samples under high-magnification quantitative observation in an epi-illumination optical microscope is described. Focus -dependent changes in the backreflection of an off-axis HeNe laser generate negative feedback signals which drive a dc motor coupled to the fine-focus knob of the microscope. This system has several advantages: (1) it is compatible and nonobstructive with concurrent data acqusition of sample intensities; (2) it requires no alteration of the sample, stage, or objective; (3) it monitors the position of sample areas very near to those under observation; (4) it is inexpensive. The system can hold a glass coverslip sample to within 0.5 μm of its preset focus position. Prismless tir

  14. Low concentrations of bisphenol a suppress thyroid hormone receptor transcription through a nongenomic mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, Zhi-Guo [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Tang, Yuan [Department of Pharmaceutics, College of Pharmacy, Third Military Medical University, 30 Yanzheng Street, Chongqing 400038 (China); Liu, Yu-Xiang [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Yuan, Ye; Zhao, Bao-Quan [Beijing Institute of Pharmacology and Toxicology, 27 Taiping Road, Beijing 100850 (China); Chao, Xi-Juan [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Zhu, Ben-Zhan, E-mail: bzhu@rcees.ac.cn [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China)

    2012-02-15

    Bisphenol (BPA) is one of the highest-volume chemicals produced worldwide, and human exposure to BPA is thought to be ubiquitous. Various rodent and in vitro studies have shown that thyroid hormone (TH) function can be impaired by BPA. However, it is still unknown if low concentrations of BPA can suppress the thyroid hormone receptor (TR) transcription. The present study aims to investigate the possible suppressing effects of low concentrations of BPA on TR transcription and the involved mechanism(s) in CV-1 cells derived from cercopithecus aethiops monkey kidneys. Using gene reporter assays, BPA at concentrations as low as 10{sup −9} M suppresses TR or steroid receptor coactivator-1(SRC-1)-enhanced TR transcription, but not reducing TR/SRC-1 interaction in mammalian two-hybrid and glutathione S-transferase pull-down studies. It has been further shown that both nuclear receptor co-repressor (N-CoR) and silencing mediator for retinoid and thyroid hormone receptors (SMRT) are recruited to the TR-β1 by BPA in the presence of physiologic concentrations of T3 or T4. However, the overexpression of β3 integrin or c-Src significantly reduces BPA-induced recruitment of N-CoR/SMRT to TR or suppression of TR transcription. Furthermore, BPA inhibits the T3/T4-mediated interassociation of the β3 integrin/c-Src/MAPK/TR-β1 pathways by the co-immunoprecipitation. These results indicate that low concentrations of BPA suppress the TR transcription by disrupting physiologic concentrations of T3/T4-mediated β3 integrin/c-Src/MAPK/TR-β1 pathways, followed by recruiting N-CoR/SMRT to TR-β1, providing a novel insight regarding the TH disruption effects of low concentration BPA. -- Highlights: ► Environmentally relevant concentrations of BPA suppress TR transcription. ► BPA recruits the N-CoR/SMRT to TR under the physiologic concentrations of T3/T4. ► BPA disrupts T3/T4-mediated β3 integrin/c-Src/MAPK/TR-β1 pathways.

  15. alpha2A-adrenergic receptors heterosynaptically regulate glutamatergic transmission in the bed nucleus of the stria terminalis.

    Science.gov (United States)

    Shields, A D; Wang, Q; Winder, D G

    2009-09-29

    Stress is a major driving force in reinstatement of drug-seeking behavior. The bed nucleus of the stria terminalis (BNST) has been identified as a key brain region in this behavior, and receives a dense input of the stress-neurotransmitter norepinephrine through the ventral noradrenergic bundle. Activation of alpha(2)-adrenergic receptors (alpha(2)-ARs) in the BNST blocks stress-induced reinstatement of drug-seeking, indicating a potentially important role for these receptors. Currently, it is unclear how alpha(2)-AR agonists elicit this behavioral action, or through which alpha(2)-AR subtype. Activation of alpha(2)-ARs decreases glutamatergic transmission in the BNST, an effect which is nearly absent in the alpha(2A)-AR knockout mouse. Here, we take advantage of a knock-in mouse in which a hemagglutinin-tagged alpha(2A)-AR was inserted into the endogenous locus, along with the alpha(2A)-AR selective agonist guanfacine, to further study the role of the alpha(2A)-AR subtype in modulation of neurotransmission in the BNST. Using immunohistochemistry, we find that alpha(2A)-ARs are highly expressed in the BNST, and that this expression is more similar in distribution to the vesicular glutamate transporters than to either norepinephrine transporter or tyrosine hydroxylase positive terminals. Using whole cell patch-clamp recordings, we show that guanfacine causes a depression of evoked excitatory and, to a more limited extent, inhibitory fast synaptic transmission. In total, these data support a prominent heterosynaptic role for alpha(2A)-ARs in modulating fast synaptic transmission in the BNST.

  16. Interactions between N-Ethylmaleimide-sensitive factor and GluA2 contribute to effects of glucocorticoid hormones on AMPA receptor function in the rodent hippocampus.

    NARCIS (Netherlands)

    Xiong, H.; Cassé, F.; Zhou, M.; Xiong, Z.Q.; Joels, M.; Martin, S.; Krugers, H.J.

    2016-01-01

    Glucocorticoid hormones, via activation of their receptors, promote memory consolidation, but the exact underlying mechanisms remain elusive. We examined how corticosterone regulates AMPA receptor (AMPAR) availability in the synapse, which is important for synaptic plasticity and memory formation.

  17. Interactions between N-Ethylmaleimide-Sensitive Factor and GluA2 contribute to effects of glucocorticoid hormones on AMPA receptor function in the rodent hippocampus

    NARCIS (Netherlands)

    Xiong, Hui; Cassé, Frédéric; Zhou, Ming; Xiong, Zhi-Qi; Joels, Marian; Martin, Stéphane; Krugers, Harm J

    Glucocorticoid hormones, via activation of their receptors, promote memory consolidation, but the exact underlying mechanisms remain elusive. We examined how corticosterone regulates AMPA receptor (AMPAR) availability in the synapse, which is important for synaptic plasticity and memory formation.

  18. Increased interferon alpha receptor 2 mRNA levels is associated with renal cell carcinoma metastasis.

    Science.gov (United States)

    Kamai, Takao; Yanai, Yoshiaki; Arai, Kyoko; Abe, Hideyuki; Yamanishi, Tomonori; Kurimoto, Masashi; Yoshida, Ken-Ichiro

    2007-08-15

    Interferon-alpha (IFN-alpha) is one of the central agents in immunotherapy for renal cell carcinoma (RCC) and binds to the IFN-alpha receptor (IFNAR). We investigated the role of IFNAR in RCC. We quantified IFNAR mRNA expression in paired tumor and non-tumor samples from the surgical specimens of 103 consecutive patients with RCC using a real-time reverse transcription polymerase chain reaction (RT-PCR), and IFNAR2 protein using Western blotting. The absolute level of IFNAR1 and IFNAR2 mRNAs in tumor and non-tumor tissues did not correlate with the malignant and metastatic profiles. The relative yields of the PCR product from the tumor tissue to that from the corresponding non-tumor tissue (T/N) for the expression of IFNAR mRNAs were calculated. While the T/N ratio of IFNAR1 did not correlate with any factor, a high T/N ratio of IFNAR2 correlated with poor differentiation (P < 0.05), local invasion (P < 0.001), and metastasis (P < 0.0001). By multivariate analysis, a high T/N ratio of IFNAR2 predicted a shortened overall survival in all cases (P < 0.05) and a shorter disease-free survival in those without metastasis (M0; 68 cases, P < 0.05). Impressively, patients with a poorer response to IFN-alpha treatment had a higher IFNAR2 T/N ratio than those who had a good response (P < 0.05). IFNAR2c protein expression was higher in the primary tumors in patients with metastases (M1; 35 cases) compared to those without ( P < 0.0001). IFNAR2 is associated with the progression of RCC.

  19. Alpha-thujone (the active component of absinthe): gamma-aminobutyric acid type A receptor modulation and metabolic detoxification.

    Science.gov (United States)

    Höld, K M; Sirisoma, N S; Ikeda, T; Narahashi, T; Casida, J E

    2000-04-11

    Alpha-thujone is the toxic agent in absinthe, a liqueur popular in the 19th and early 20th centuries that has adverse health effects. It is also the active ingredient of wormwood oil and some other herbal medicines and is reported to have antinociceptive, insecticidal, and anthelmintic activity. This study elucidates the mechanism of alpha-thujone neurotoxicity and identifies its major metabolites and their role in the poisoning process. Four observations establish that alpha-thujone is a modulator of the gamma-aminobutyric acid (GABA) type A receptor. First, the poisoning signs (and their alleviation by diazepam and phenobarbital) in mice are similar to those of the classical antagonist picrotoxinin. Second, a strain of Drosophila specifically resistant to chloride channel blockers is also tolerant to alpha-thujone. Third, alpha-thujone is a competitive inhibitor of [(3)H]ethynylbicycloorthobenzoate binding to mouse brain membranes. Most definitively, GABA-induced peak currents in rat dorsal root ganglion neurons are suppressed by alpha-thujone with complete reversal after washout. alpha-Thujone is quickly metabolized in vitro by mouse liver microsomes with NADPH (cytochrome P450) forming 7-hydroxy-alpha-thujone as the major product plus five minor ones (4-hydroxy-alpha-thujone, 4-hydroxy-beta-thujone, two other hydroxythujones, and 7,8-dehydro-alpha-thujone), several of which also are detected in the brain of mice treated i.p. with alpha-thujone. The major 7-hydroxy metabolite attains much higher brain levels than alpha-thujone but is less toxic to mice and Drosophila and less potent in the binding assay. The other metabolites assayed are also detoxification products. Thus, alpha-thujone in absinthe and herbal medicines is a rapid-acting and readily detoxified modulator of the GABA-gated chloride channel.

  20. Snake alpha-neurotoxin binding site on the Egyptian cobra (Naja haje) nicotinic acetylcholine receptor Is conserved.

    Science.gov (United States)

    Takacs, Z; Wilhelmsen, K C; Sorota, S

    2001-09-01

    Evolutionary success requires that animal venoms are targeted against phylogenetically conserved molecular structures of fundamental physiological processes. Species producing venoms must be resistant to their action. Venoms of Elapidae snakes (e.g., cobras, kraits) contain alpha-neurotoxins, represented by alpha-bungarotoxin (alpha-BTX) targeted against the nicotinic acetylcholine receptor (nAChR) of the neuromuscular junction. The model which presumes that cobras (Naja spp., Elapidae) have lost their binding site for conspecific alpha-neurotoxins because of the unique amino acid substitutions in their nAChR polypeptide backbone per se is incompatible with the evolutionary theory that (1) the molecular motifs forming the alpha-neurotoxin target site on the nAChR are fundamental for receptor structure and/or function, and (2) the alpha-neurotoxin target site is conserved among Chordata lineages. To test the hypothesis that the alpha-neurotoxin binding site is conserved in Elapidae snakes and to identify the mechanism of resistance against conspecific alpha-neurotoxins, we cloned the ligand binding domain of the Egyptian cobra (Naja haje) nAChR alpha subunit. When expressed as part of a functional Naja/mouse chimeric nAChR in Xenopus oocytes, this domain confers resistance against alpha-BTX but does not alter responses induced by the natural ligand acetylcholine. Further mutational analysis of the Naja/mouse nAChR demonstrated that an N-glycosylation signal in the ligand binding domain that is unique to N. haje is responsible for alpha-BTX resistance. However, when the N-glycosylation signal is eliminated, the nAChR containing the N. haje sequence is inhibited by alpha-BTX with a potency that is comparable to that in mammals. We conclude that the binding site for conspecific alpha-neurotoxin in Elapidae snakes is conserved in the nAChR ligand binding domain polypeptide backbone per se. This conclusion supports the hypothesis that animal toxins are targeted against

  1. Recombinant human growth-regulated oncogene-alpha induces T lymphocyte chemotaxis. A process regulated via IL-8 receptors by IFN-gamma, TNF-alpha, IL-4, IL-10, and IL-13

    DEFF Research Database (Denmark)

    Jinquan, T; Frydenberg, Jane; Mukaida, N

    1995-01-01

    receptors on the cells. This process can be augmented by IFN-gamma and TNF-alpha, and inhibited by IL-4, IL-10, and IL-13. In addition, we also document that on T lymphocytes there exist IL-8 receptors that can be up-regulated by IFN-gamma, TNF-alpha, and IL-2. Our results demonstrate that rhGRO-alpha gene...

  2. Resveratrol Inhibits Alpha-Melanocyte-Stimulating Hormone Signaling, Viability, and Invasiveness in Melanoma Cells

    Directory of Open Access Journals (Sweden)

    Yu-Jen Chen

    2013-01-01

    Full Text Available Melanoma is a malignancy with high potential to invasion and treatment resistance. The α-melanocyte-stimulating hormone (α-MSH signal transduction involving Wnt/β-catenin, c-Kit, and microphthalmia-associated transcription factor (MITF, a known pathway to produce melanin, has been demonstrated as one of cancer stem cell characteristics. This study was aimed to examine the effect of resveratrol, an abundant ingredient of grape and medicinal plants, on α-MSH signaling, viability, and invasiveness in melanoma cells. By α-MSH treatment, the melanin production in B16 melanoma cells was augmented as a validation for activation of α-MSH signaling. The upregulated expression of α-MSH signaling-related molecules β-catenin, c-Kit, and MITF was suppressed by resveratrol and/or STI571 treatment. Nuclear translocation of MITF, a hallmark of α-MSH signaling activation, was inhibited by combined treatment of resveratrol and STI571. At effective concentration, resveratrol and/or STI571 inhibited cell viability and α-MSH-activated matrix metalloproteinase- (MMP-9 expression and invasion capacity of B16 melanoma cells. In conclusion, resveratrol enhances STI571 effect on suppressing the α-MSH signaling, viability, and invasiveness in melanoma cells. It implicates that resveratrol may have potential to modulate the cancer stem cell characteristics of melanoma.

  3. Agonist-promoted desensitization and phosphorylation of. cap alpha. /sub 1/-adrenergic receptors coupled to stimulation of phosphatidylinositol metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Leeb-Lundberg, L.M.F.; Cotecchia, S.; Caron, M.G.; Lefkowitz, R.J.

    1986-03-05

    In the DDT/sub 1/ MF-2 hamster vas deferens smooth muscle cell line the ..cap alpha../sub 1/-adrenergic receptor (..cap alpha../sub 1/-AR) agonist norepinephrine (NE) promotes rapid attenuation of ..cap alpha../sub 1/-AR-mediated phosphatidylinositol (PI) metabolism which is paralleled by rapid phosphorylation of the ..cap alpha../sub 1/-AR. Cells were labeled by incubation with /sup 32/P/sub i/. Coincubation with NE (100 ..mu..M) significantly increases the rate of /sup 32/P-labeling of both PI and phosphatidic acid. Pretreatment of cells with 100 ..mu..M NE (in the presence of 1 ..mu..M propranolol to prevent ..beta..-AR interactions) results in a drastic attenuation of the NE response on PI metabolism. ..cap alpha../sub 1/-AR from labeled cells can be solubilized and purified by affinity chromatography on Affigel-A55414 and wheat germ agglutinin agarose chromatography. SDS-PAGE of purified ..cap alpha../sub 1/-AR shows a NE-promoted increase in phosphorylation of the M/sub r/ 80K ligand binding peptide. Stoichiometry of phosphorylation increases from approx. 1 mol phosphate/mol ..cap alpha../sub 1/-AR in the basal condition to approx. 2.5 after NE treatment. Both desensitization and phosphorylation are rapid being maximal within 10-20 min of agonist exposure. These results together with previous findings that phorbol esters promote rapid ..cap alpha../sub 1/-AR uncoupling and phosphorylation suggest that receptor phosphorylation is an important mechanism of regulation of ..cap alpha../sub 1/-AR receptor responsiveness.

  4. Competitive RT-PCR Strategy for Quantitative Evaluation of the Expression of Tilapia (Oreochromis niloticus Growth Hormone Receptor Type I

    Directory of Open Access Journals (Sweden)

    Rodríguez-Mallon Alina

    2009-01-01

    Full Text Available Abstract Quantization of gene expression requires that an accurate measurement of a specific transcript is made. In this paper, a quantitative reverse transcription-polymerase chain reaction (RT-PCR by competition for tilapia growth hormone receptor type I is designed and validated. This experimental procedure was used to determine the abundance of growth hormone receptor type I transcript in different tilapia tissues. The results obtained with this developed competitive RT-PCR were similar to real-time PCR results reported recently. This protocol provides a reliable alternative, but less expensive than real-time PCR to quantify specific genes.

  5. Competitive RT-PCR Strategy for Quantitative Evaluation of the Expression of Tilapia (Oreochromis niloticus Growth Hormone Receptor Type I

    Directory of Open Access Journals (Sweden)

    Rodríguez-Mallon Alina

    2009-03-01

    Full Text Available Abstract Quantization of gene expression requires that an accurate measurement of a specific transcript is made. In this paper, a quantitative reverse transcription-polymerase chain reaction (RT-PCR by competition for tilapia growth hormone receptor type I is designed and validated. This experimental procedure was used to determine the abundance of growth hormone receptor type I transcript in different tilapia tissues. The results obtained with this developed competitive RT-PCR were similar to real-time PCR results reported recently. This protocol provides a reliable alternative, but less expensive than real-time PCR to quantify specific genes.

  6. The nuclear receptor ROR(alpha) exerts a bi-directional regulation of IL-6 in resting and reactive astrocytes.

    Science.gov (United States)

    Journiac, Nathalie; Jolly, Sarah; Jarvis, Christopher; Gautheron, Vanessa; Rogard, Monique; Trembleau, Alain; Blondeau, Jean-Paul; Mariani, Jean; Vernet-der Garabedian, Béatrice

    2009-12-15

    Astrocytes and one of their products, IL-6, not only support neurons but also mediate inflammation in the brain. Retinoid-related orphan receptor-alpha (RORalpha) transcription factor has related roles, being neuro-protective and, in peripheral tissues, anti-inflammatory. We examined the relation of ROR(alpha) to astrocytes and IL-6 using normal and ROR(alpha) loss-of-function mutant mice. We have shown ROR(alpha) expression in astrocytes and its up-regulation by pro-inflammatory cytokines. We have also demonstrated that ROR(alpha) directly trans-activates the Il-6 gene. We suggest that this direct control is necessary to maintain IL-6 basal level in the brain and may be a link between the neuro-supportive roles of ROR(alpha), IL-6, and astrocytes. Furthermore, after inflammatory stimulation, the absence of ROR(alpha) results in excessive IL-6 up-regulation, indicating that ROR(alpha) exerts an indirect repression probably via the inhibition of the NF-kappaB signaling. Thus, our findings indicate that ROR(alpha) is a pluripotent molecular player in constitutive and adaptive astrocyte physiology.

  7. Regulation of the human SLC25A20 expression by peroxisome proliferator-activated receptor alpha in human hepatoblastoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Tachibana, Keisuke, E-mail: nya@phs.osaka-u.ac.jp [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Takeuchi, Kentaro; Inada, Hirohiko [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Yamasaki, Daisuke [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); The Center for Advanced Medical Engineering and Informatics, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Ishimoto, Kenji [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Tanaka, Toshiya; Hamakubo, Takao; Sakai, Juro; Kodama, Tatsuhiko [Laboratory for System Biology and Medicine, Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8904 (Japan); Doi, Takefumi [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); The Center for Advanced Medical Engineering and Informatics, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2009-11-20

    Solute carrier family 25, member 20 (SLC25A20) is a key molecule that transfers acylcarnitine esters in exchange for free carnitine across the mitochondrial membrane in the mitochondrial {beta}-oxidation. The peroxisome proliferator-activated receptor alpha (PPAR{alpha}) is a ligand-activated transcription factor that plays an important role in the regulation of {beta}-oxidation. We previously established tetracycline-regulated human cell line that can be induced to express PPAR{alpha} and found that PPAR{alpha} induces the SLC25A20 expression. In this study, we analyzed the promoter region of the human slc25a20 gene and showed that PPAR{alpha} regulates the expression of human SLC25A20 via the peroxisome proliferator responsive element.

  8. The selective alpha7 nicotinic acetylcholine receptor agonist A-582941 activates immediate early genes in limbic regions of the forebrain

    DEFF Research Database (Denmark)

    Thomsen, M S; Mikkelsen, J D; Timmermann, D B

    2008-01-01

    Due to the cognitive-enhancing properties of alpha7 nicotinic acetylcholine receptor (alpha7 nAChR) agonists, they have attracted interest for the treatment of cognitive disturbances in schizophrenia. Schizophrenia typically presents in late adolescence or early adulthood. It is therefore important...... to study whether alpha7 nAChR stimulation activates brain regions involved in cognition in juvenile as well as adult individuals. Here, we compared the effects of the novel and selective alpha7 nAChR agonist 2-methyl-5-(6-phenyl-pyridazin-3-yl)-octahydro-pyrrolo[3,4-c]pyrrole (A-582941) in the juvenile...... regions critically involved in working memory and attention. Furthermore, this effect is more pronounced in juvenile than adult rats, indicating that the juvenile forebrain is more responsive to alpha7 nAChR stimulation. This observation may be relevant in the treatment of juvenile-onset schizophrenia....

  9. Mitochondria and the insect steroid hormone receptor (EcR): A complex relationship.

    Science.gov (United States)

    Vafopoulou, Xanthe; Steel, Colin G H

    2016-10-01

    The actions of the insect steroid molting hormones, ecdysteroids, on the genome of target cells has been well studied, but little is known of their extranuclear actions. We previously showed in Rhodnius prolixus that much of the ecdysteroid receptor (EcR) resides in the cytoplasm of various cell types and undergoes shuttling between nucleus and cytoplasm with circadian periodicity, possibly using microtubules as tracks for translocation to the nucleus. Here we report that cytoplasmic EcR appears to be also involved in extranuclear actions of ecdysteroids by association with the mitochondria. Western blots of subcellular fractions of brain lysates revealed that EcR is localized in the mitochondrial fraction, indicating an intimate association of EcR with mitochondria. Confocal laser microscopy and immunohistochemistry using anti-EcR revealed abundant co-localization of EcR with mitochondria in brain neurons and their axons, especially intense in the subplasmalemmal region, raising the possibility of EcR involvement in mitochondrial functions in subplasmalemmal microdomains. When mitochondria are dispersed by disruption of microtubules with colchicine, EcR remains associated with mitochondria showing strong receptor association with mitochondria. Treatment in vitro with ecdysteroids of brains of developmentally arrested R. prolixus (containing neither ecdysteroids nor EcR) induces EcR and abundant co-localization with mitochondria in neurons, concurrently with a sharp increase of the mitochondrial protein COX 1, suggesting involvement of EcR in mitochondrial function. These findings align EcR with various vertebrate steroid receptors, where actions of steroid receptors on mitochondria are widely known and suggest that steroid receptors across distant phyla share similar functional attributes. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Hypothalamic expression of anorexigenic and orexigenic hormone receptors in obese females Neotomodon alstoni: effect of fasting.

    Science.gov (United States)

    Báez-Ruiz, Adrián; Luna-Moreno, Dalia; Carmona-Castro, Agustín; Cárdenas-Vázquez, René; Díaz-Muñoz, Mauricio; Carmona-Alcocer, Vania; Fuentes-Granados, Citlalli; Manuel, Miranda-Anaya

    2014-01-01

    Obesity is a world problem that requires a better understanding of its physiological and genetic basis, as well as the mechanisms by which the hypothalamus controls feeding behavior. The volcano mouse Neotomodon alstoni develops obesity in captivity when fed with regular chow diet, providing a novel model for the study of obesity. Females develop obesity more often than males; therefore, in this study, we analysed in females, in proestrous lean and obese, the differences in hypothalamus expression of receptors for leptin, ghrelin (growth hormone secretagogue receptor GHS-R), and VPAC, and correlates for plasma levels of total ghrelin. The main comparisons are between mice fed ad libitum and mice after 24 hours of fasting. Mice above 65 g body weight were considered obese, based on behavioral and physiological parameters such as food intake, plasma free fatty acids, and glucose tolerance. Hypothalamic tissue from obese and lean mice was analysed by western blot. Our results indicate that after ad libitum food access, obese mice show no significant differences in hypothalamic leptin receptors, but a significant increase of 60% in the GHS-R, and a nearly 62% decrease in VPAC2 was noted. After a 24-hour fast, plasma ghrelin increased nearly two fold in both lean and obese mice; increases of hypothalamic leptin receptors and GHS-R were also noted, while VPAC2 did not change significantly; levels of plasma free fatty acids were 50% less after fasting in obese than in lean animals. Our results indicate that in obese N. alstoni mice, the levels of orexigenic receptors in the hypothalamus correlate with overfeeding, and the fact that lean and obese females respond in different ways to a metabolic demand such as a 24-hour fast.

  11. Ligand-stimulated downregulation of the alpha interferon receptor: role of protein kinase D2.

    Science.gov (United States)

    Zheng, Hui; Qian, Juan; Varghese, Bentley; Baker, Darren P; Fuchs, Serge

    2011-02-01

    Alpha interferon (IFN-α) controls homeostasis of hematopoietic stem cells, regulates antiviral resistance, inhibits angiogenesis, and suppresses tumor growth. This cytokine is often used to treat cancers and chronic viral infections. The extent of cellular responses to IFN-α is limited by the IFN-induced ubiquitination and degradation of the IFN-α/β receptor chain 1 (IFNAR1) chain of the cognate receptor. IFNAR1 ubiquitination is facilitated by the βTrcp E3 ubiquitin ligase that is recruited to IFNAR1 upon its degron phosphorylation, which is induced by the ligand. Here we report identification of protein kinase D2 (PKD2) as a kinase that mediates the ligand-inducible phosphorylation of IFNAR1 degron and enables binding of βTrcp to the receptor. Treatment of cells with IFN-α induces catalytic activity of PKD2 and stimulates its interaction with IFNAR1. Expression and kinase activity of PKD2 are required for the ligand-inducible stimulation of IFNAR1 ubiquitination and endocytosis and for accelerated proteolytic turnover of IFNAR1. Furthermore, inhibition or knockdown of PKD2 robustly augments intracellular signaling induced by IFN-α and increases the efficacy of its antiviral effects. The mechanisms of the ligand-inducible elimination of IFNAR1 are discussed, along with the potential medical significance of this regulation.

  12. A novel GABA(A) alpha 5 receptor inhibitor with therapeutic potential.

    Science.gov (United States)

    Ling, István; Mihalik, Balázs; Etherington, Lori-An; Kapus, Gábor; Pálvölgyi, Adrienn; Gigler, Gábor; Kertész, Szabolcs; Gaál, Attila; Pallagi, Katalin; Kiricsi, Péter; Szabó, Éva; Szénási, Gábor; Papp, Lilla; Hársing, László G; Lévay, György; Spedding, Michael; Lambert, Jeremy J; Belelli, Delia; Barkóczy, József; Volk, Balázs; Simig, Gyula; Gacsályi, István; Antoni, Ferenc A

    2015-10-05

    Novel 2,3-benzodiazepine and related isoquinoline derivatives, substituted at position 1 with a 2-benzothiophenyl moiety, were synthesized to produce compounds that potently inhibited the action of GABA on heterologously expressed GABAA receptors containing the alpha 5 subunit (GABAA α5), with no apparent affinity for the benzodiazepine site. Substitutions of the benzothiophene moiety at position 4 led to compounds with drug-like properties that were putative inhibitors of extra-synaptic GABAA α5 receptors and had substantial blood-brain barrier permeability. Initial characterization in vivo showed that 8-methyl-5-[4-(trifluoromethyl)-1-benzothiophen-2-yl]-1,9-dihydro-2H-[1,3]oxazolo[4,5-h][2,3]benzodiazepin-2-one was devoid of sedative, pro-convulsive or motor side-effects, and enhanced the performance of rats in the object recognition test. In summary, we have discovered a first-in-class GABA-site inhibitor of extra-synaptic GABAA α5 receptors that has promising drug-like properties and warrants further development. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Expression and Role of Gonadotropin-Releasing Hormone 2 and Its Receptor in Mammals

    Directory of Open Access Journals (Sweden)

    Amy T. Desaulniers

    2017-12-01

    Full Text Available Gonadotropin-releasing hormone 1 (GnRH1 and its receptor (GnRHR1 drive mammalian reproduction via regulation of the gonadotropins. Yet, a second form of GnRH (GnRH2 and its receptor (GnRHR2 also exist in mammals. GnRH2 has been completely conserved throughout 500 million years of evolution, signifying high selection pressure and a critical biological role. However, the GnRH2 gene is absent (e.g., rat or inactivated (e.g., cow and sheep in some species but retained in others (e.g., human, horse, and pig. Likewise, many species (e.g., human, chimpanzee, cow, and sheep retain the GnRHR2 gene but lack the appropriate coding sequence to produce a full-length protein due to gene coding errors; although production of GnRHR2 in humans remains controversial. Certain mammals lack the GnRHR2 gene (e.g., mouse or most exons entirely (e.g., rat. In contrast, old world monkeys, musk shrews, and pigs maintain the coding sequence required to produce a functional GnRHR2. Like GnRHR1, GnRHR2 is a 7-transmembrane, G protein-coupled receptor that interacts with Gαq/11 to mediate cell signaling. However, GnRHR2 retains a cytoplasmic tail and is only 40% homologous to GnRHR1. A role for GnRH2 and its receptor in mammals has been elusive, likely because common laboratory models lack both the ligand and receptor. Uniquely, both GnRH2 and GnRHR2 are ubiquitously expressed; transcript levels are abundant in peripheral tissues and scarcely found in regions of the brain associated with gonadotropin secretion, suggesting a divergent role from GnRH1/GnRHR1. Indeed, GnRH2 and its receptor are not physiological modulators of gonadotropin secretion in mammals. Instead, GnRH2 and GnRHR2 coordinate the interaction between nutritional status and sexual behavior in the female brain. Within peripheral tissues, GnRH2 and its receptor are novel regulators of reproductive organs. GnRH2 and GnRHR2 directly stimulate steroidogenesis within the porcine testis. In the female, GnRH2 and

  14. Evaluation of [{sup 125}I]7{alpha}-O-iodoally diprenophine as a new potential SPECT opioid receptor imaging agent

    Energy Technology Data Exchange (ETDEWEB)

    Wang, R.F.; Tafani, J.A.M.; Frances, B.; Bergon, M.; Coulais, Y.; Zajac, J. M.; Guiraud, R

    1997-08-01

    A new iodinated diprenorphine analog, [{sup 125}I]7{alpha}-O-iodoallyl diprenorphine ([{sup 125}I]7{alpha}-O-IA-DPN), was prepared by iododestannylation and characterized. As an opioid antagonist, this agent showed very high affinity (K{sub i} = 0.4 {+-} 0.2 nM) and 63% of specific binding by in vitro and in vivo binding studies. Inhibition curves indicated that this tracer labeled with the same affinities to three opioid receptors ({mu} = {delta} = {kappa}). The findings demonstrate that this proposed compound appears to be a potential radioprobe for future study of opioid receptors by in vivo SPECT.

  15. Receptor tyrosine phosphatase R-PTP-alpha is tyrosine-phosphorylated and associated with the adaptor protein Grb2

    DEFF Research Database (Denmark)

    Su, J; Batzer, A; Sap, J

    1994-01-01

    Receptor tyrosine phosphatases (R-PTPases) have generated interest because of their suspected involvement in cellular signal transduction. The adaptor protein Grb2 has been implicated in coupling receptor tyrosine kinases to Ras. We report that a ubiquitous R-PTPase, R-PTP-alpha, is tyrosine......-phosphorylated and associated in vivo with the Grb2 protein. This association can be reproduced in stably and transiently transfected cells, as well as in vitro using recombinant Grb2 protein. Association requires the presence of an intact SH2 domain in Grb2, as well as tyrosine phosphorylation of R-PTP-alpha. This observation...

  16. Thyroid hormone resistance syndrome caused by heterozygous A317T mutation in thyroid hormone receptor β gene: Report of one Chinese pedigree and review of the literature.

    Science.gov (United States)

    Guo, Qing-Hua; Wang, Bao-An; Wang, Chen-Zhi; Wang, Min; Lu, Ju-Ming; Lv, Zhao-Hui; Mu, Yi-Ming

    2016-08-01

    Thyroid hormone resistance syndrome (THRS) is a rare disorder with increased concentrations of free thyroxine (FT4) and triiodothyronine (FT3), but normal or slightly increased thyroid-stimulating hormone (TSH). The mutations in the thyroid hormone receptor β (THRβ) gene are thought to be the main pathogenesis. The aims of this study were to present 1 pedigree of Chinese THRS, summarize their clinical characteristics, and analyze the gene mutation. The clinical characteristics and thyroid function of the proband and his family members were collected. Gene mutations were analyzed by DNA sequencing. The proband and his mother exhibited symptoms of hyperthyroidism, such as palpitations, heat intolerance, and perspiration. The mother also had atrial fibrillation. The rest of the kindred did not display clinical manifestations of hyper- or hypothyroidism. DNA sequencing revealed a heterozygous G>A missense mutation at position 949 in Exon 9 of THRβ both in the patient and his mother, which led to the transition from alanine to threonine at position 317 of THRβ protein (A317T), whereas the rest of the kindred did not share this mutation. The proband and his mother were diagnosed with pituitary resistance to thyroid hormone. Oral administration of methimazole was stopped and β-receptor blockers were administrated. We present 1 pedigree of THRS with heterozygous A317T mutation in THRβ gene in the proband and his mother, which is the first reported mutation in Chinese and provides a comprehensive review of available literature.

  17. Pharmacologic management of bone-related complications and bone metastases in postmenopausal women with hormone receptor-positive breast cancer

    Directory of Open Access Journals (Sweden)

    Yardley DA

    2016-05-01

    Full Text Available Denise A Yardley1,2 1Sarah Cannon Research Institute, Nashville, TN, USA; 2Tennessee Oncology, Nashville, TN, USA Abstract: There is a high risk for bone loss and skeletal-related events, including bone metastases, in postmenopausal women with hormone receptor-positive breast cancer. Both the disease itself and its therapeutic treatments can negatively impact bone, resulting in decreases in bone mineral density and increases in bone loss. These negative effects on the bone can significantly impact morbidity and mortality. Effective management and minimization of bone-related complications in postmenopausal women with hormone receptor-positive breast cancer remain essential. This review discusses the current understanding of molecular and biological mechanisms involved in bone turnover and metastases, increased risk for bone-related complications from breast cancer and breast cancer therapy, and current and emerging treatment strategies for managing bone metastases and bone turnover in postmenopausal women with hormone receptor-positive breast cancer. Keywords: breast cancer, bone metastases, hormone receptor-positive, bone-related complications, interventions, management and management strategies, estrogen receptor-positive

  18. Identification of a gonadotropin-releasing hormone receptor orthologue in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Sgro Jean-Yves

    2006-11-01

    Full Text Available Abstract Background The Caenorhabditis elegans genome is known to code for at least 1149 G protein-coupled receptors (GPCRs, but the GPCR(s critical to the regulation of reproduction in this nematode are not yet known. This study examined whether GPCRs orthologous to human gonadotropin-releasing hormone receptor (GnRHR exist in C. elegans. Results Our sequence analyses indicated the presence of two proteins in C. elegans, one of 401 amino acids [GenBank: NP_491453; WormBase: F54D7.3] and another of 379 amino acids [GenBank: NP_506566; WormBase: C15H11.2] with 46.9% and 44.7% nucleotide similarity to human GnRHR1 and GnRHR2, respectively. Like human GnRHR1, structural analysis of the C. elegans GnRHR1 orthologue (Ce-GnRHR predicted a rhodopsin family member with 7 transmembrane domains, G protein coupling sites and phosphorylation sites for protein kinase C. Of the functionally important amino acids in human GnRHR1, 56% were conserved in the C. elegans orthologue. Ce-GnRHR was actively transcribed in adult worms and immunoanalyses using antibodies generated against both human and C. elegans GnRHR indicated the presence of a 46-kDa protein, the calculated molecular mass of the immature Ce-GnRHR. Ce-GnRHR staining was specifically localized to the germline, intestine and pharynx. In the germline and intestine, Ce-GnRHR was localized specifically to nuclei as revealed by colocalization with a DNA nuclear stain. However in the pharynx, Ce-GnRHR was localized to the myofilament lattice of the pharyngeal musculature, suggesting a functional role for Ce-GnRHR signaling in the coupling of food intake with reproduction. Phylogenetic analyses support an early evolutionary origin of GnRH-like receptors, as evidenced by the hypothesized grouping of Ce-GnRHR, vertebrate GnRHRs, a molluscan GnRHR, and the adipokinetic hormone receptors (AKHRs and corazonin receptors of arthropods. Conclusion This is the first report of a GnRHR orthologue in C. elegans, which

  19. Evaluation of 1-azabicyclo[2.2.2]oct-3-yl {alpha}-fluoroalkyl-{alpha}-hydroxy-{alpha}-phenylacetates as potential ligands for the study of muscarinic receptor density by positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Luo, H.; Hasan, A.; Sood, V.; McRee, R.C.; Zeeberg, B.; Reba, R.C.; McPherson, D.W.; Knapp, F.F

    1996-04-01

    Both 1-azabicyclo[2.2.2]oct-3-yl {alpha}-(1-fluoroeth-2-yl)-{alpha}-hydroxy-{alpha}-phenylacetate (FQNE, 5) and 1-azabicyclo[2.2.2]oct-3-yl {alpha}-(1-fluoropent-5-yl)-{alpha}-hydroxy-{alpha}-phenylacetate (FQNPe, 6) were prepared and evaluated as potential candidates for the determination of muscarinic cholinergic receptor (mAChR) density by positron emission tomography (PET). The results of in vitro binding assays demonstrated that although both 5 and 6 had high binding affinities for m{sub 1} and m{sub 2} mAChR subtypes, 6 displayed a higher affinity (nM, m{sub 1}; K{sub D}, 0.45, m{sub 2}; K{sub D}, 3.53) as compared to 5 (nM, m{sub 1}; K{sub D}, 12.5, m{sub 2}; K{sub D}, 62.8). It was observed that pretreatment of female Fisher rats with either 5 or 6 prior to the i.v. administration of Z-(-)(-)-[{sup 131}I]-IQNP, a high-affinity muscarinic ligand, significantly blocked the uptake of radioactivity in the brain and heart measured 3 h postinjection of the radiolabeled ligand. These new fluoro QNB analogues represent important target ligands for evaluation as potential receptor imaging agents in conjunction with PET.

  20. Discovery of an Oxybenzylglycine Based Peroxisome Proliferator Activated Receptor [alpha] Selective Agonist 2-((3-((2-(4-Chlorophenyl)-5-methyloxazol-4-yl)methoxy)benzyl)(methoxycarbonyl)amino)acetic Acid (BMS-687453)

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jun; Kennedy, Lawrence J.; Shi, Yan; Tao, Shiwei; Ye, Xiang-Yang; Chen, Stephanie Y.; Wang, Ying; Hernndez, Andrs S.; Wang, Wei; Devasthale, Pratik V.; Chen, Sean; Lai, Zhi; Zhang, Hao; Wu, Shung; Smirk, Rebecca A.; Bolton, Scott A.; Ryono, Denis E.; Zhang, Huiping; Lim, Ngiap-Kie; Chen, Bang-Chi; Locke, Kenneth T.; O’Malley, Kevin M.; Zhang, Litao; Srivastava, Rai Ajit; Miao, Bowman; Meyers, Daniel S.; Monshizadegan, Hossain; Search, Debra; Grimm, Denise; Zhang, Rongan; Harrity, Thomas; Kunselman, Lori K.; Cap, Michael; Kadiyala, Pathanjali; Hosagrahara, Vinayak; Zhang, Lisa; Xu, Carrie; Li, Yi-Xin; Muckelbauer, Jodi K.; Chang, Chiehying; An, Yongmi; Krystek, Stanley R.; Blanar, Michael A.; Zahler, Robert; Mukherjee, Ranjan; Cheng, Peter T.W.; Tino, Joseph A. (BMS)

    2010-04-12

    An 1,3-oxybenzylglycine based compound 2 (BMS-687453) was discovered to be a potent and selective peroxisome proliferator activated receptor (PPAR) {alpha} agonist, with an EC{sub 50} of 10 nM for human PPAR{alpha} and 410-fold selectivity vs human PPAR{gamma} in PPAR-GAL4 transactivation assays. Similar potencies and selectivity were also observed in the full length receptor co-transfection assays. Compound 2 has negligible cross-reactivity against a panel of human nuclear hormone receptors including PPAR{delta}. Compound 2 demonstrated an excellent pharmacological and safety profile in preclinical studies and thus was chosen as a development candidate for the treatment of atherosclerosis and dyslipidemia. The X-ray cocrystal structures of the early lead compound 12 and compound 2 in complex with PPAR{alpha} ligand binding domain (LBD) were determined. The role of the crystal structure of compound 12 with PPAR{alpha} in the development of the SAR that ultimately resulted in the discovery of compound 2 is discussed.

  1. Structure and chromosomal localization of the human antidiuretic hormone receptor gene

    Energy Technology Data Exchange (ETDEWEB)

    Seibold, A.; Brabet, P.; Rosenthal, W.; Birnbaumer, M. (Baylor College of Medicine, Houston, TX (United States))

    1992-11-01

    Applying a genomic DNA-expression approach, the authors cloned the gene and cDNA coding for the human antidiuretic hormone receptor, also called vasopressin V2 receptor' (V2R). The nucleotide sequence of both cloned DNAs provided the information to elucidate the structure of the isolated transcriptional unit. The structure of this gene is unusual in that it is the first G protein-coupled receptor gene that contains two very small intervening sequences, the second of which separates the region encoding the seventh transmembrane region from the rest of the open reading frame. The sequence information was used to synthesize appropriate oligonucleotides to be used as primers in the PCR. The V2R gene was localized by PCR using DNA from hybrid cells as template. The gene was found to reside in the q28-qter portion of the human X chromosome, a region identified as the locus for congential nephrogenic diabetes insipidus. 27 refs., 4 figs.

  2. Magnesium modulates parathyroid hormone secretion and upregulates parathyroid receptor expression at moderately low calcium concentration.

    Science.gov (United States)

    Rodríguez-Ortiz, Maria E; Canalejo, Antonio; Herencia, Carmen; Martínez-Moreno, Julio M; Peralta-Ramírez, Alan; Perez-Martinez, Pablo; Navarro-González, Juan F; Rodríguez, Mariano; Peter, Mirjam; Gundlach, Kristina; Steppan, Sonja; Passlick-Deetjen, Jutta; Muñoz-Castañeda, Juan R; Almaden, Yolanda

    2014-02-01

    The interest on magnesium (Mg) has grown since clinical studies have shown the efficacy of Mg-containing phosphate binders. However, some concern has arisen for the potential effect of increased serum Mg on parathyroid hormone (PTH) secretion. Our objective was to evaluate the direct effect of Mg in the regulation of the parathyroid function; specifically, PTH secretion and the expression of parathyroid cell receptors: CaR, the vitamin D receptor (VDR) and FGFR1/Klotho. The work was performed in vitro by incubating intact rat parathyroid glands in different calcium (Ca) and Mg concentrations. Increasing Mg concentrations from 0.5 to 2 mM produced a left shift of PTH-Ca curves. With Mg 5 mM, the secretory response was practically abolished. Mg was able to reduce PTH only if parathyroid glands were exposed to moderately low Ca concentrations; with normal-high Ca concentrations, the effect of Mg on PTH inhibition was minor or absent. After 6-h incubation at a Ca concentration of 1.0 mM, the expression of parathyroid CaR, VDR, FGFR1 and Klotho (at mRNA and protein levels) was increased with a Mg concentration of 2.0 when compared with 0.5 mM. Mg reduces PTH secretion mainly when a moderate low calcium concentration is present; Mg also modulates parathyroid glands function through upregulation of the key cellular receptors CaR, VDR and FGF23/Klotho system.

  3. Overexpression of Endometrial Estrogen Receptor-Alpha in The Window of Implantation in Women with Unexplained Infertility

    Directory of Open Access Journals (Sweden)

    Mehran Dorostghoal

    2018-01-01

    Full Text Available Background Failure in the endometrial receptivity may account for a significant number of infertility cases including unexplained infertility in women. Reduction in the endometrial estrogen receptor-alpha (ER-α expression during implantation may be a critical event that coincides with the expression of specific genes and the formation of a receptive endometrium. The aim of the present study was to assess the expression of ER-α in the mid-secretory phase in the endometrium of women with unexplained infertility. Materials and Methods This case-control study was carried out on randomly selected fertile (n=10 and infertile (n=16 women whose source of infertility remained unexplained. We evaluated the expression of ER-α and glycode-lin-A (GdA through mRNA level measurement with real-time polymerase chain reaction (PCR in the endometrium of fertile women and patients suffering from unexplained infertility and fertile women. Endometrial biopsies of each subject were collected during a single menstrual cycle 7 days after the peak of luteinizing hormone (LH+7. Results Endometrial expression level of ER-α was significantly (P<0.05 higher in the patients with unexplained infertility compared to the control. Significantly (P<0.05 lower levels of GdA expression were seen in women with unexplained infertility. A statistically non-significant negative correlation was observed between ER-α and GdA mRNA expression. Conclusion Our findings demonstrate that reduction in the endometrial GdA expression is associated with elevated expression of ER-α in mid-luteal phase. Disruption in the endometrial ER-α expression, which leads to defects in uterine receptivity, may contribute to unexplained infertility.

  4. Estrogen receptor beta impacts hormone-induced alternative mRNA splicing in breast cancer cells.

    Science.gov (United States)

    Dago, Dougba Noel; Scafoglio, Claudio; Rinaldi, Antonio; Memoli, Domenico; Giurato, Giorgio; Nassa, Giovanni; Ravo, Maria; Rizzo, Francesca; Tarallo, Roberta; Weisz, Alessandro

    2015-05-09

    Estrogens play an important role in breast cancer (BC) development and progression; when the two isoforms of the estrogen receptor (ERα and ERβ) are co-expressed each of them mediate specific effects of these hormones in BC cells. ERβ has been suggested to exert an antagonist role toward the oncogenic activities of ERα, and for this reason it is considered an oncosuppressor. As clinical evidence regarding a prognostic role for this receptor subtype in hormone-responsive BC is still limited and conflicting, more knowledge is required on the biological functions of ERβ in cancer cells. We have previously described the ERβ and ERα interactomes from BC cells, identifying specific and distinct patterns of protein interactions for the two receptors. In particular, we identified factors involved in mRNA splicing and maturation as important components of both ERα and ERβ pathways. Guided by these findings, here we performed RNA sequencing to investigate in depth the differences in the early transcriptional events and RNA splicing patterns induced by estradiol in cells expressing ERα alone or ERα and ERβ. Exon skipping was the most abundant splicing event in the post-transcriptional regulation by estradiol. We identified several splicing events induced by ERα alone and by ERα+ERβ, demonstrating for the first time that ERβ significantly affects estrogen-induced splicing in BC cells, as revealed by modification of a subset of ERα-dependent splicing by ERβ, as well as by the presence of splicing isoforms only in ERβ+cells. In particular, we observed that ERβ+BC cell lines exhibited around 2-fold more splicing events than the ERβ- cells. Interestingly, we identified putative direct targets of ERβ-mediated alternative splicing by correlating the genomic locations of ERβ and ERα binding sites with estradiol-induced differential splicing in the corresponding genes. Taken together, these results demonstrate that ERβ significantly affects estrogen

  5. The breast cancer hormone receptor retesting controversy in Newfoundland and Labrador, Canada: lessons for the health system.

    Science.gov (United States)

    Gregory, Deborah M; Parfrey, Patrick S

    2010-01-01

    The treatment of newly diagnosed breast cancer patients with hormonal treatment is determined by the presence of estrogen receptor and progesterone receptor status in breast cancer. In Newfoundland and Labrador (NL), 425 of 1088 (39.1%) patients who had original "negative" receptor tests conducted between 1997 and 2005, had positive results upon retesting in a specialized laboratory. This commentary addresses (1) the diagnostic utility of estrogen and progesterone testing for breast cancer in general, (2) specific testing problems that occurred in NL, (3) scientific problems associated with retesting, and (4) the impact on public trust and the resulting legal and political responses that occurred as a result of the adverse events associated with false-negative hormone receptor tests. Finally, the lessons learned will be discussed including known high false-negative rates associated with the tests and the bias associated with retesting, the need for quality assurance and national standards, public education, and appropriate communication with patients and the public.

  6. Receptor localization of steroid hormones and drugs: discoveries through the use of thaw-mount and dry-mount autoradiography

    OpenAIRE

    Stumpf, W.E.

    1998-01-01

    The history of receptor autoradiography, its development and applications, testify to the utility of this histochemical technique for localizing radiolabeled hormones and drugs at cellular and subcellular sites of action in intact tissues. Localization of diffusible compounds has been a challenge that was met through the introduction of the "thaw-mount" and "dry-mount" autoradiographic techniques thirty years ago. With this cellular receptor autoradiography, used alone or combined with other ...

  7. Structure of the T cell receptor in a Ti alpha V beta 2, alpha V beta 8-positive T cell line

    DEFF Research Database (Denmark)

    Hou, X; Dietrich, J; Kuhlmann, J

    1994-01-01

    not known; however, it has been suggested that each TcR contains two Ti dimers. To gain insight into the structure of the TcR we constructed a Ti alpha V beta 2, alpha V beta 8-positive T cell line which expressed the endogenous human TiV beta 8 and the transfected mouse TiV beta 2 both in association......The T cell receptor (TcR) is composed of at least six different polypeptide chains consisting of the clonotypic Ti heterodimer (Ti alpha beta or Ti gamma delta) and the noncovalently associated CD3 chains (CD3 gamma delta epsilon zeta). The exact number of subunits constituting the TcR is still...... with the endogenous Ti alpha and CD3 chains at the cell surface. Preclearing experiments with radioiodinated cell lysate prepared with digitonin lysis buffer demonstrated that depleting the lysate of Ti alpha V beta 8 by immunoprecipitation with anti V beta 8 monoclonal antibody (mAb) did not reduce the amount of Ti...

  8. Inhibition of MAP kinase promotes the recruitment of corepressor SMRT by tamoxifen-bound estrogen receptor alpha and potentiates tamoxifen action in MCF-7 cells.

    Science.gov (United States)

    Hong, Wei; Chen, Linfeng; Li, Juan; Yao, Zhi

    2010-05-28

    Estrogen receptor alpha (ERalpha), a ligand controlled transcription factor, plays an important role in breast cancer growth and endocrine therapy. Tamoxifen (TAM) antagonizes ERalpha activity and has been applied in breast cancer treatment. TAM-bound ERalpha associates with nuclear receptor-corepressors. Mitogen-activated protein kinase (MAPK) has been elucidated to result in cross-talk between growth factor and ERalpha mediated signaling. We show that activated MAPK represses interaction of TAM-bound ERalpha with silencing mediator for retinoid and thyroid hormone receptors (SMRT) and inhibits the recruitment of SMRT by ERalpha to certain estrogen target genes. Blockade of MAPK signaling cascade with MEK inhibitor U0126 promotes the interaction and subsequently inhibits ERalpha activity via enhanced recruitment of SMRT, leading to reduced expression of ERalpha target genes. The growth rate of MCF-7 cells was decelerated when treated with both TAM and U0126. Moreover, the growth of MCF-7 cells stably expressing SMRT showed a robust repression in the presence of TAM and U0126. These results suggest that activated MAPK signaling cascade attenuates antagonist-induced recruitment of SMRT to ERalpha, suggesting corepressor mediates inhibition of ERalpha transactivation and breast cancer cell growth by antagonist. Taken together, our finding indicates combination of antagonist and MAPK inhibitor could be a helpful approach for breast cancer therapy. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  9. Ligand binding affinities of arctigenin and its demethylated metabolites to estrogen receptor alpha.

    Science.gov (United States)

    Jin, Jong-Sik; Lee, Jong-Hyun; Hattori, Masao

    2013-01-16

    Phytoestrogens are defined as plant-derived compounds with estrogen-like activities according to their chemical structures and activities. Plant lignans are generally categorized as phytoestrogens. It was reported that (-)-arctigenin, the aglycone of arctiin, was demethylated to (-)-dihydroxyenterolactone (DHENL) by Eubacterium (E.) sp. ARC-2. Through stepwise demethylation, E. sp. ARC-2 produced six intermediates, three mono-desmethylarctigenins and three di-desmethylarctigenins. In the present study, ligand binding affinities of (-)-arctigenin and its seven metabolites, including DHENL, were investigated for an estrogen receptor alpha, and found that demethylated metabolites had stronger binding affinities than (-)-arctigenin using a ligand binding screen assay method. The IC(50) value of (2R,3R)-2-(4-hydroxy-3-methoxybenzyl)-3-(3,4-dihydroxybenzyl)-butyrolactone was 7.9 × 10⁻⁴ M.

  10. Ligand Binding Affinities of Arctigenin and Its Demethylated Metabolites to Estrogen Receptor Alpha

    Directory of Open Access Journals (Sweden)

    Masao Hattori

    2013-01-01

    Full Text Available Phytoestrogens are defined as plant-derived compounds with estrogen-like activities according to their chemical structures and activities. Plant lignans are generally categorized as phytoestrogens. It was reported that (−-arctigenin, the aglycone of arctiin, was demethylated to (−-dihydroxyenterolactone (DHENL by Eubacterium (E. sp. ARC-2. Through stepwise demethylation, E. sp. ARC-2 produced six intermediates, three mono-desmethylarctigenins and three di-desmethylarctigenins. In the present study, ligand binding affinities of (−-arctigenin and its seven metabolites, including DHENL, were investigated for an estrogen receptor alpha, and found that demethylated metabolites had stronger binding affinities than (−-arctigenin using a ligand binding screen assay method. The IC50 value of (2R,3R-2-(4-hydroxy-3-methoxybenzyl-3-(3,4-dihydroxybenzyl-butyrolactone was 7.9 × 10−4 M.

  11. Receptor-like protein-tyrosine phosphatase alpha specifically inhibits insulin-increased prolactin gene expression

    DEFF Research Database (Denmark)

    Jacob, K K; Sap, J; Stanley, F M

    1998-01-01

    A physiologically relevant response to insulin, stimulation of prolactin promoter activity in GH4 pituitary cells, was used as an assay to study the specificity of protein-tyrosine phosphatase function. Receptor-like protein-tyrosine phosphatase alpha (RPTPalpha) blocks the effect of insulin...... to increase prolactin gene expression but potentiates the effects of epidermal growth factor and cAMP on prolactin promoter activity. RPTPalpha was the only protein-tyrosine phosphatase tested that did this. Thus, the effect of RPTPalpha on prolactin-chloramphenicol acetyltransferase (CAT) promoter activity...... is specific by two criteria. A number of potential RPTPalpha targets were ruled out by finding (a) that they are not affected or (b) that they are not on the pathway to insulin-increased prolactin-CAT activity. The negative effect of RPTPalpha on insulin activation of the prolactin promoter is not due...

  12. THE ROLE OF THE SOLUBLE TNF-ALPHA RECEPTORS IN TREATMENT OF JUVENILE IDIOPATHIC ARTHRITIS

    Directory of Open Access Journals (Sweden)

    T. M. Bzarova

    2012-01-01

    Full Text Available The results of the study of etanercept (soluble tumor necrosis factor alpha receptors efficacy and safety in treatment of 97 patients with early and late onset of juvenile idiopathic arthritis are demonstrated in this article. The observation period was 12 months. In 48 weeks of anti-TNF treatment the achievement of clinical remission, decrease and normalization of laboratory markers of disease activity, complete restoration of joints function and improvement of life quality was established in 100% of children with early onset and 71% of children with late onset of arthritis. The drug was withdrawn in 13 (14% patients: in 5 (6% due to inefficiency, in 3 (4% — due to development of side effects.

  13. Receptor protein tyrosine phosphatase alpha is essential for hippocampal neuronal migration and long-term potentiation

    DEFF Research Database (Denmark)

    Petrone, Angiola; Battaglia, Fortunato; Wang, Cheng

    2003-01-01

    Despite clear indications of their importance in lower organisms, the contributions of protein tyrosine phosphatases (PTPs) to development or function of the mammalian nervous system have been poorly explored. In vitro studies have indicated that receptor protein tyrosine phosphatase alpha (RPTPa....... However, these synapses are unable to undergo long-term potentiation. Mice lacking RPTPalpha also underperform in the radial-arm water-maze test. These studies identify RPTPalpha as a key mediator of neuronal migration and synaptic plasticity....... neuronal migration. The migratory abnormality likely results from a radial glial dysfunction rather than from a neuron-autonomous defect. In spite of this aberrant development, basic synaptic transmission from the Schaffer collateral pathway to CA1 pyramidal neurons remains intact in Ptpra(-/-) mice...

  14. Vegetable and fruit consumption and the risk of hormone receptor-defined breast cancer in the EPIC cohort.

    Science.gov (United States)

    Emaus, Marleen J; Peeters, Petra H M; Bakker, Marije F; Overvad, Kim; Tjønneland, Anne; Olsen, Anja; Romieu, Isabelle; Ferrari, Pietro; Dossus, Laure; Boutron-Ruault, Marie Christine; Baglietto, Laura; Fortner, Renée T; Kaaks, Rudolf; Boeing, Heiner; Trichopoulou, Antonia; Lagiou, Pagona; Trichopoulos, Dimitrios; Masala, Giovanna; Pala, Valeria; Panico, Salvatore; Tumino, Rosario; Polidoro, Silvia; Skeie, Guri; Lund, Eiliv; Weiderpass, Elisabete; Quirós, J Ramón; Travier, Noémie; Sánchez, María-José; Chirlaque, Maria-Dolores; Ardanaz, Eva; Dorronsoro, Miren; Winkvist, Anna; Wennberg, Maria; Bueno-de-Mesquita, H Bas; Khaw, Kay-Tee; Travis, Ruth C; Key, Timothy J; Aune, Dagfinn; Gunter, Marc; Riboli, Elio; van Gils, Carla H

    2016-01-01

    The recent literature indicates that a high vegetable intake and not a high fruit intake could be associated with decreased steroid hormone receptor-negative breast cancer risk. This study aimed to investigate the association between vegetable and fruit intake and steroid hormone receptor-defined breast cancer risk. A total of 335,054 female participants in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort were included in this study (mean ± SD age: 50.8 ± 9.8 y). Vegetable and fruit intake was measured by country-specific questionnaires filled out at recruitment between 1992 and 2000 with the use of standardized procedures. Cox proportional hazards models were stratified by age at recruitment and study center and were adjusted for breast cancer risk factors. After a median follow-up of 11.5 y (IQR: 10.1-12.3 y), 10,197 incident invasive breast cancers were diagnosed [3479 estrogen and progesterone receptor positive (ER+PR+); 1021 ER and PR negative (ER-PR-)]. Compared with the lowest quintile, the highest quintile of vegetable intake was associated with a lower risk of overall breast cancer (HRquintile 5-quintile 1: 0.87; 95% CI: 0.80, 0.94). Although the inverse association was most apparent for ER-PR- breast cancer (ER-PR-: HRquintile 5-quintile 1: 0.74; 95% CI: 0.57, 0.96; P-trend = 0.03; ER+PR+: HRquintile 5-quintile 1: 0.91; 95% CI: 0.79, 1.05; P-trend = 0.14), the test for heterogeneity by hormone receptor status was not significant (P-heterogeneity = 0.09). Fruit intake was not significantly associated with total and hormone receptor-defined breast cancer risk. This study supports evidence that a high vegetable intake is associated with lower (mainly hormone receptor-negative) breast cancer risk. © 2016 American Society for Nutrition.

  15. Human insulin analogues modified at the B26 site reveal a hormone conformation that is undetected in the receptor complex

    Energy Technology Data Exchange (ETDEWEB)

    Žáková, Lenka; Kletvíková, Emília; Lepšík, Martin; Collinsová, Michaela [Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6 (Czech Republic); Watson, Christopher J.; Turkenburg, Johan P. [The University of York, Heslington, York YO10 5DD (United Kingdom); Jiráček, Jiří [Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6 (Czech Republic); Brzozowski, Andrzej M., E-mail: marek.brzozowski@york.ac.uk [The University of York, Heslington, York YO10 5DD (United Kingdom); Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6 (Czech Republic)

    2014-10-01

    [AsnB26]- and [GlyB26]-insulin mutants attain a B26-turn like fold without assistance of chemical modifications. Their structures match the insulin receptor interface and expand the spectrum of insulin conformations. The structural characterization of the insulin–insulin receptor (IR) interaction still lacks the conformation of the crucial B21–B30 insulin region, which must be different from that in its storage forms to ensure effective receptor binding. Here, it is shown that insulin analogues modified by natural amino acids at the TyrB26 site can represent an active form of this hormone. In particular, [AsnB26]-insulin and [GlyB26]-insulin attain a B26-turn-like conformation that differs from that in all known structures of the native hormone. It also matches the receptor interface, avoiding substantial steric clashes. This indicates that insulin may attain a B26-turn-like conformation upon IR binding. Moreover, there is an unexpected, but significant, binding specificity of the AsnB26 mutant for predominantly the metabolic B isoform of the receptor. As it is correlated with the B26 bend of the B-chain of the hormone, the structures of AsnB26 analogues may provide the first structural insight into the structural origins of differential insulin signalling through insulin receptor A and B isoforms.

  16. 2,5-Diphenylfuran-based pure antiestrogens with selectivity for the estrogen receptor alpha.

    Science.gov (United States)

    Zimmermann, Jochen; Liebl, Renate; von Angerer, Erwin

    2005-02-01

    The estrogen receptor alpha (ERalpha) is understood to play an important role in the progression of breast cancer. Therefore, pure antiestrogens with a preference for this receptor form are of interest as new agents for the treatment of this malignancy. Several chemical structures with selective binding affinity for ERalpha have been identified and might be useful for the synthesis of ERalpha-selective pure antiestrogens. In this study we applied the 2,5-diphenylfuran system which is closely related to the triphenylfurans described by others. Various side chains with amino and/or sulfur functions were linked to C3 to convert the furans to estrogen antagonists without residual estrogenic activity. The degree of alpha-selectivity which ranges from 2.5- to 236-fold is strongly influenced by the alkyl group at C4. Antiestrogenic potency was determined in MCF-7/2a breast cancer cells stably transfected with a luciferase gene under the control of an ERE. The 2,5-bis(4-hydroxyphenyl)furan with an ethyl substituent and a 6-[N-methyl-N-(3-pentylthiopropyl)amino]hexyl side chain exerted the strongest antiestrogenic effect in this series with an IC(50) value of 50 nM in cells stimulated with 1 nM estradiol. The RBA values of this derivative were 18% (ERalpha) and 3.4% (ERbeta) of estradiol, respectively. It inhibited the growth of wild-type MCF-7 cells with an IC(50) value of 22 nM. The data show that the 2,5-diphenylfuran system is appropriate for the development of pure antiestrogens with preference for ERalpha.

  17. The growth hormone receptor gene-disrupted mouse fails to respond to an intermittent fasting diet.

    Science.gov (United States)

    Arum, Oge; Bonkowski, Michael S; Rocha, Juliana S; Bartke, Andrzej

    2009-12-01

    The interaction of longevity-conferring genes with longevity-conferring diets is poorly understood. The growth hormone receptor gene-disrupted (GHR-KO) mouse is long lived; and this longevity is not responsive to 30% caloric restriction, in contrast to wild-type animals from the same strain. To determine whether this may have been limited to a particular level of dietary restriction, we subjected GHR-KO mice to a different dietary restriction regimen, an intermittent fasting diet. The intermittent fasting diet increased the survivorship and improved insulin sensitivity of normal males, but failed to affect either parameter in GHR-KO mice. From the results of two paradigms of dietary restriction, we postulate that GHR-KO mice would be resistant to any manner of dietary restriction; potentially due to their inability to further enhance insulin sensitivity. Insulin sensitivity may be a mechanism and/or a marker of the lifespan extending potential of an intervention.

  18. The structure and organization of the human follicle-stimulating hormone receptor (FSHR) gene

    Energy Technology Data Exchange (ETDEWEB)

    Gromoll, J; Pekel, E.; Nieschlag, E. [Institute of Reproductive Medicine of the Univ., Muenster (Germany)

    1996-07-15

    The structure and organization of the human follicle-stimulating hormone receptor (FSHR) gene were determined by either screening a phage library of human genomic DNA or applying the long PCR technique to amplify different exon pairs with their corresponding introns. The FSHR gene spans a region of 54 kb and consists of 10 exons and 9 introns. Most of the extracellular domain is encoded by 9 exons, ranging in length between 69 and 251 bp; the C-terminal part of the extracellular domain, the transmembrane domain, and the intracellular domain are encoded by the large exon 10 (1234 bp). Overall the gene encodes 695 amino acids. The structure of the human FSHR displays a striking similarity to that of the previously characterized rat FSHR gene, with a high degree of conservation in exon sizes and exon/intron junctions. 20 refs., 2 tabs.

  19. Epigenetics of Estrogen Receptor Signaling: Role in Hormonal Cancer Progression and Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Mann, Monica; Cortez, Valerie [Department of Cellular and Structural Biology, UTHSCSA, 7703 Floyd Curl Drive, San Antonio, TX 78229 (United States); Vadlamudi, Ratna K., E-mail: vadlamudi@uthscsa.edu [Department of Obstetrics and Gynecology, UTHSCSA, 7703 Floyd Curl Drive, San Antonio, TX 78229 (United States)

    2011-03-29

    Estrogen receptor (ERα) signaling plays a key role in hormonal cancer progression. ERα is a ligand-dependent transcription factor that modulates gene transcription via recruitment to the target gene chromatin. Emerging evidence suggests that ERα signaling has the potential to contribute to epigenetic changes. Estrogen stimulation is shown to induce several histone modifications at the ERα target gene promoters including acetylation, phosphorylation and methylation via dynamic interactions with histone modifying enzymes. Deregulation of enzymes involved in the ERα -mediated epigenetic pathway could play a vital role in ERα driven neoplastic processes. Unlike genetic alterations, epigenetic changes are reversible, and hence offer novel therapeutic opportunities to reverse ERα driven epigenetic changes. In this review, we summarize current knowledge on mechanisms by which ERα signaling potentiates epigenetic changes in cancer cells via histone modifications.

  20. Taltirelin is a superagonist at the human thyrotropin-releasing hormone receptor

    Science.gov (United States)

    Thirunarayanan, Nanthakumar; Raaka, Bruce M.; Gershengorn, Marvin C.

    2012-01-01

    Taltirelin (TAL) is a thyrotropin-releasing hormone (TRH) analog that is approved for use in humans in Japan. In this study, we characterized TAL binding to and signaling by the human TRH receptor (TRH-R) in a model cell system. We found that TAL exhibited lower binding affinities than TRH and lower signaling potency via the inositol-1,4,5-trisphosphate/calcium pathway than TRH. However, TAL exhibited higher intrinsic efficacy than TRH in stimulating inositol-1,4,5-trisphosphate second messenger generation. This is the first study that elucidates the pharmacology of TAL at TRH-R and shows that TAL is a superagonist at TRH-R. We suggest the superagonism exhibited by TAL may in part explain its higher activity in mediating central nervous system effects in humans compared to TRH. PMID:23087672

  1. Taltirelin is a superagonist at the human thyrotropin-releasing hormone receptor

    Directory of Open Access Journals (Sweden)

    Nanthakumar eThirunarayanan

    2012-10-01

    Full Text Available Taltirelin (TAL is a thyrotropin-releasing hormone (TRH analog that is approved for use in humans in Japan. In this study, we characterized TAL binding to and signaling by the human TRH receptor (TRH-R in a model cell system. We found that TAL exhibited lower binding affinities than TRH and lower signaling potency via the inositol-1,4,5-trisphosphate/calcium pathway than TRH. However, TAL exhibited higher intrinsic efficacy than TRH in stimulating inositol-1,4,5-trisphosphate second messenger generation. This is the first study that elucidates the pharmacology of TAL at TRH-R and shows that TAL is a superagonist at TRH-R. We suggest the superagonism exhibited by TAL may in part explain its higher activity in mediating CNS effects in humans compared to TRH.

  2. Thyroid hormone receptor regulates most genes independently of fibroblast growth factor 21 in liver.

    Science.gov (United States)

    Zhang, Aijun; Sieglaff, Douglas H; York, Jean Philippe; Suh, Ji Ho; Ayers, Stephen D; Winnier, Glenn E; Kharitonenkov, Alexei; Pin, Christopher; Zhang, Pumin; Webb, Paul; Xia, Xuefeng

    2015-03-01

    Thyroid hormone (TH) acts through specific receptors (TRs), which are conditional transcription factors, to induce fibroblast growth factor 21 (FGF21), a peptide hormone that is usually induced by fasting and that influences lipid and carbohydrate metabolism via local hepatic and systemic endocrine effects. While TH and FGF21 display overlapping actions when administered, including reductions in serum lipids, according to the current models these hormones act independently in vivo. In this study, we examined mechanisms of regulation of FGF21 expression by TH and tested the possibility that FGF21 is required for induction of hepatic TH-responsive genes. We confirm that active TH (triiodothyronine (T3)) and the TRβ-selective thyromimetic GC1 increase FGF21 transcript and peptide levels in mouse liver and that this effect requires TRβ. T3 also induces FGF21 in cultured hepatocytes and this effect involves direct actions of TRβ1, which binds a TRE within intron 2 of FGF21. Gene expression profiles of WT and Fgf21-knockout mice are very similar, indicating that FGF21 is dispensable for the majority of hepatic T3 gene responses. A small subset of genes displays diminished T3 response in the absence of FGF21. However, most of these are not obviously directly involved in T3-dependent hepatic metabolic processes. Consistent with these results, T3-dependent effects on serum cholesterol are maintained in the Fgf21(-/-) background and we observe no effect of the Fgf21-knockout background on serum triglycerides and glucose. Our findings indicate that T3 regulates the genes involved in classical hepatic metabolic responses independently of FGF21. © 2015 Society for Endocrinology.

  3. Thyroid hormone receptor inhibits hepatoma cell migration through transcriptional activation of Dickkopf 4

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Hsiang-Cheng; Liao, Chen-Hsin [Department of Biochemistry, School of Medicine, Chang-Gung University, Taoyuan 333, Taiwan, ROC (China); Huang, Ya-Hui [Medical Research Central, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan, ROC (China); Wu, Sheng-Ming; Tsai, Chung-Ying; Liao, Chia-Jung; Tseng, Yi-Hsin; Lin, Yang-Hsiang; Chen, Cheng-Yi; Chung, I-Hsiao; Wu, Tzu-I [Department of Biochemistry, School of Medicine, Chang-Gung University, Taoyuan 333, Taiwan, ROC (China); Chen, Wei-Jan [First Cardiovascular Division, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan, ROC (China); Lin, Kwang-Huei, E-mail: khlin@mail.cgu.edu.tw [Department of Biochemistry, School of Medicine, Chang-Gung University, Taoyuan 333, Taiwan, ROC (China)

    2013-09-13

    Highlights: •T{sub 3} affects DKK4 mRNA and protein expression in HepG2-TR cells. •Regulation of DKK4 by T{sub 3} is at transcriptional level. •DKK4 overexpression suppresses hepatoma cell metastasis. -- Abstract: Triiodothyronine (T{sub 3}) is a potent form of thyroid hormone mediates several physiological processes including cellular growth, development, and differentiation via binding to the nuclear thyroid hormone receptor (TR). Recent studies have demonstrated critical roles of T{sub 3}/TR in tumor progression. Moreover, long-term hypothyroidism appears to be associated with the incidence of human hepatocellular carcinoma (HCC), independent of other major HCC risk factors. Dickkopf (DKK) 4, a secreted protein that antagonizes the canonical Wnt signaling pathway, is induced by T{sub 3} at both mRNA and protein levels in HCC cell lines. However, the mechanism underlying T{sub 3}-mediated regulation of DKK4 remains unknown. In the present study, the 5′ promoter region of DKK4 was serially deleted, and the reporter assay performed to localize the T{sub 3} response element (TRE). Consequently, we identified an atypical direct repeat TRE between nucleotides −1645 and −1629 conferring T{sub 3} responsiveness to the DKK4 gene. This region was further validated using chromatin immunoprecipitation (ChIP) and electrophoretic mobility shift assay (EMSA). Stable DKK4 overexpression in SK-Hep-1 cells suppressed cell invasion and metastatic potential, both in vivo andin vitro, via reduction of matrix metalloproteinase-2 (MMP-2) expression. Our findings collectively suggest that DKK4 upregulated by T{sub 3}/TR antagonizes the Wnt signal pathway to suppress tumor cell progression, thus providing new insights into the molecular mechanism underlying thyroid hormone activity in HCC.

  4. Genomic organization and chromosomal localization of the human and mouse genes encoding the {alpha} receptor component for ciliary neurotrophic factor

    Energy Technology Data Exchange (ETDEWEB)

    Valenzuela, D.M.; Rojas, E.; McClain, J. [Regeneron Pharmaceuticals, Inc., Tarrytown, NY (United States)] [and others

    1995-01-01

    Ciliary neurotrophic factor (CNTF) has recently been found to share receptor components with, and to be structurally related to, a family of broadly acting cytokines, including interleukin-6, leukemia inhibitory factor, and oncostatin M. However, the CNTF receptor complex also includes a CNTF-specific component known as CNTF receptor {alpha} (CNTFR{alpha}). Here we describe the molecular cloning of the human and mouse genes encoding CNTFR. We report that the human and mouse genes have an identical intron-exon structure that correlates well with the domain structure of CNTFR{alpha}. That is, the signal peptide and the immunoglobulin-like domain are each encoded by single exons, the cytokine receptor-like domain is distributed among 4 exons, and the C-terminal glycosyl phosphatidylinositol recognition domain in encoded by the final coding exon. The position of the introns within the cytokine receptor-like domain corresponds to those found in other members of the cytokine receptor superfamily. Confirming a recent study using radiation hybrids, we have also mapped the human CNTFR gene to chromosome band 9p13 and the mouse gene to a syntenic region of chromosome 4. 24 refs., 4 figs.

  5. Activation of peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}) suppresses postprandial lipidemia through fatty acid oxidation in enterocytes

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Rino [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan); Takahashi, Nobuyuki, E-mail: nobu@kais.kyoto-u.ac.jp [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan); Murota, Kaeko [Department of Life Science, School of Science and Engineering, Kinki University, Osaka 770-8503 (Japan); Yamada, Yuko [Laboratory of Physiological Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan); Niiya, Saori; Kanzaki, Noriyuki; Murakami, Yoko [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan); Moriyama, Tatsuya [Department of Applied Cell Biology, Graduate School of Agriculture, Kinki University, Nara 631-8505 (Japan); Goto, Tsuyoshi; Kawada, Teruo [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2011-06-24

    Highlights: {yields} PPAR{alpha} activation increased mRNA expression levels of fatty acid oxidation-related genes in human intestinal epithelial Caco-2 cells. {yields} PPAR{alpha} activation also increased oxygen consumption rate and CO{sub 2} production and decreased secretion of triglyceride and ApoB from Caco-2 cells. {yields} Orally administration of bezafibrate increased mRNA expression levels of fatty acid oxidation-related genes and CO{sub 2} production in small intestinal epithelial cells. {yields} Treatment with bezafibrate decreased postprandial serum concentration of triglyceride after oral injection of olive oil in mice. {yields} It suggested that intestinal lipid metabolism regulated by PPAR{alpha} activation suppresses postprandial lipidemia. -- Abstract: Activation of peroxisome proliferator-activated receptor (PPAR)-{alpha} which regulates lipid metabolism in peripheral tissues such as the liver and skeletal muscle, decreases circulating lipid levels, thus improving hyperlipidemia under fasting conditions. Recently, postprandial serum lipid levels have been found to correlate more closely to cardiovascular diseases than fasting levels, although fasting hyperlipidemia is considered an important risk of cardiovascular diseases. However, the effect of PPAR{alpha} activation on postprandial lipidemia has not been clarified. In this study, we examined the effects of PPAR{alpha} activation in enterocytes on lipid secretion and postprandial lipidemia. In Caco-2 enterocytes, bezafibrate, a potent PPAR{alpha} agonist, increased mRNA expression levels of fatty acid oxidation-related genes, such as acyl-CoA oxidase, carnitine palmitoyl transferase, and acyl-CoA synthase, and oxygen consumption rate (OCR) and suppressed secretion levels of both triglycerides and apolipoprotein B into the basolateral side. In vivo experiments revealed that feeding high-fat-diet containing bezafibrate increased mRNA expression levels of fatty acid oxidation-related genes and

  6. Postnatal ovarian development and its relationship with steroid hormone receptors in JiNing Grey goats.

    Science.gov (United States)

    Shi, YunZhi; Wang, ShuYing; Bai, Shu; Huang, LiBo; Hou, YanMeng

    2015-03-01

    In this work, we examined the ovarian development and its relationship with steroid hormone receptors levels and the precocious puberty in JiNing Gray goats by using optical microscopy, immunohistochemistry, quantitative real-time RT-PCR (qPCR) and Western blotting. We found that in the ovaries of neonatal kids, high level of receptors for estrogen (ERα and ERβ) and progesterone (PR) and their mRNA were observed along with growing follicles. From 0 to 30 days of age, the weight and volume of ovaries increased significantly and the boundary between the inner and outer cortex disappeared, while the expression of ERα, ERβ and PR and their mRNA decreased sharply. When 60 days old, the animals began to ovulate; the expression of ERα, ERβ and PR and their mRNA significantly increased, and the animals reached puberty. On day 90, the animals manifested sexual maturity with biggest mature follicles 6.18mm in diameter, the expression of ERβ and PR protein and their mRNA was maintained at a high level, with decreased expression of ERα and its mRNA. Before puberty, the expression of ovarian ERα (prepubertal dominant receptor) and it's mRNA was significantly higher than that of ERβ (dominant receptor after sexual maturity). The results showed that JiNing Grey goats' ovaries had fast development and early maturation, and ERα, ERβ and PR protein and mRNA expression in the ovary had distinct specificity for time and space, which may be closely related to the strain's progenitive characteristics. Copyright © 2015. Published by Elsevier B.V.

  7. Molecular characterization and functional analyses of a diapause hormone receptor-like gene in parthenogenetic Artemia.

    Science.gov (United States)

    Ye, Hui-Li; Li, Dong-Rui; Yang, Jin-Shu; Chen, Dian-Fu; De Vos, Stephanie; Vuylsteke, Marnik; Sorgeloos, Patrick; Van Stappen, Gilbert; Bossier, Peter; Nagasawa, Hiromichi; Yang, Wei-Jun

    2017-04-01

    In arthropods, mature females under certain conditions produce and release encysted gastrula embryos that enter diapause, a state of obligate dormancy. The process is presumably regulated by diapause hormone (DH) and diapause hormone receptor (DHR) that were identified in the silkworm, Bombyx mori and other insects. However, the molecular structure and function of DHR in crustaceans remains unknown. Here, a DHR-like gene from parthenogenetic Artemia (Ar-DHR) was isolated and sequenced. The cDNA sequence consists of 1410bp with a 1260-bp open reading frame encoding a protein consisting of 420 amino acid residues. The results of real-time PCR (qRT-PCR) and Western blot analysis showed that the mRNA and protein of Ar-DHR were mainly expressed at the diapause stage. Furthermore, we found that Ar-DHR was located on the cell membrane of the pre-diapause cyst but in the cytoplasm of the diapause cyst by analysis of immunofluorescence. In vivo knockdown of Ar-DHR by RNA interference (RNAi) and antiserum neutralization consistently inhibited diapause cysts formation. The results indicated that Ar-DHR plays an important role in the induction and maintenance of embryonic diapause in Artemia. Thus, our findings provide an insight into the regulation of diapause formation in Artemia and the function of Ar-DHR. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Structure-activity relations in binding of perfluoroalkyl compounds to human thyroid hormone T3 receptor.

    Science.gov (United States)

    Ren, Xiao-Min; Zhang, Yin-Feng; Guo, Liang-Hong; Qin, Zhan-Fen; Lv, Qi-Yan; Zhang, Lian-Ying

    2015-02-01

    Perfluoroalkyl compounds (PFCs) have been shown to disrupt thyroid functions through thyroid hormone receptor (TR)-mediated pathways, but direct binding of PFCs with TR has not been demonstrated. We investigated the binding interactions of 16 structurally diverse PFCs with human TR, their activities on TR in cells, and the activity of perfluorooctane sulfonate (PFOS) in vivo. In fluorescence competitive binding assays, most of the 16 PFCs were found to bind to TR with relative binding potency in the range of 0.0003-0.05 compared with triiodothyronine (T3). A structure-binding relationship for PFCs was observed, where fluorinated alkyl chain length longer than ten, and an acid end group were optimal for TR binding. In thyroid hormone (TH)-responsive cell proliferation assays, PFOS, perfluorohexadecanoic acid, and perfluorooctadecanoic acid exhibited agonistic activity by promoting cell growth. Furthermore, similar to T3, PFOS exposure promoted expression of three TH upregulated genes and inhibited three TH downregulated genes in amphibians. Molecular docking analysis revealed that most of the tested PFCs efficiently fit into the T3-binding pocket in TR and formed a hydrogen bond with arginine 228 in a manner similar to T3. The combined in vitro, in vivo, and computational data strongly suggest that some PFCs disrupt the normal activity of TR pathways by directly binding to TR.

  9. Association of the luteinizing hormone/choriogonadotropin receptor gene polymorphism with polycystic ovary syndrome.

    Science.gov (United States)

    Bassiouny, Yasmin Ahmed; Rabie, Walaa Ahmed; Hassan, Ayman Ahmed; Darwish, Rania Kamal

    2014-06-01

    This study aimed at evaluating possible associations of the single nucleotide polymorphism (SNP) in luteinizing hormone/choriogonadotropin receptor (LHCGR) gene G935A and polycystic ovary syndrome (PCOS) phenotype. The study included 100 PCOS female patients and 60 healthy female control subjects. The patients were recruited from the Gynecology out-patient clinic, Kasr Al-Aini Hospital, Cairo University. All candidates underwent full history taking and clinical examination with calculation of body mass index. Serum and EDTA samples were collected from each patient after a written consent. A hormonal profile was done for each patient as well as DNA analysis of the G935A polymorphism of LHCGR gene. In PCOS group, 26% were homozygous (AA), 27% were heterozygous (GA) and 47% were wild genotype (GG), while in controls 30% were heterozygous and 70% were wild genotype (OR: 2.25; CI: 1.16-4.386; p value: 0.012). The homozygous 935A individuals were at higher risk to develop PCOS than controls (OR: 1.80; CI: 1.54-2.09; p value genetic variant, which is associated with PCOS in a sample of the Egyptian population. These results may provide an opportunity to test this SNP at the LHCGR gene in fertile or infertile women with family history to assess their risk of PCOS.

  10. The frequency of follicle stimulating hormone receptor gene polymorphisms in Iranian infertile men with azoospermia

    Directory of Open Access Journals (Sweden)

    Behrouz Gharesi-Fard

    2015-11-01

    Full Text Available Background: Azoospermia is the medical condition of a man not having any measurable level of sperm in his semen. Follicle stimulating hormone (FSH is a member of the glycoprotein hormone family that plays an important role in human reproduction because of its essential role in normal spermatogenesis. Various Single Nucleotide Polymorphisms (SNPs have been reported within FSH receptor (FSHR gene that may affect the receptor function. Objective: The present study aimed to investigate the correlation between two FSHR SNPs at positions A919G, A2039G, and susceptibility to azoospermia in a group of Iranian azoospermic men. The association between FSH levels within the sera and A919G and A2039G alleles and genotypes were also investigated. Materials and Methods: This case control study was performed on 212 men with azoospermia (126 non-obstructive and 86 obstructive and 200 healthy Iranian men. Two FSHR gene SNPs were genotyped using PCR-RFLP method. The relationship between FSH levels within the sera and A919G and A2039G alleles and genotypes were also investigated. Results: Statistical analysis indicated that at A919G position, AA genotype and A allele were more frequent in obstructive azoospermia cases compared to non-obstructive or normal men (p=0.001. Regarding A2039G polymorphisms, no significant difference was observed between both azoospermia groups and the controls. The mean level of serum FSH was higher in the non-obstructive men compared to the obstructive patients (23.8 versus 13.8, respectively, p= 0.04. Conclusion: The results of the present study indicated that the genetic polymorphisms in the FSHR gene might increase the susceptibility to azoospermia in Iranian men.

  11. Actin-Sorting Nexin 27 (SNX27)-Retromer Complex Mediates Rapid Parathyroid Hormone Receptor Recycling*

    Science.gov (United States)

    McGarvey, Jennifer C.; Xiao, Kunhong; Bowman, Shanna L.; Mamonova, Tatyana; Zhang, Qiangmin; Bisello, Alessandro; Sneddon, W. Bruce; Ardura, Juan A.; Jean-Alphonse, Frederic; Vilardaga, Jean-Pierre; Puthenveedu, Manojkumar A.; Friedman, Peter A.

    2016-01-01

    The G protein-coupled parathyroid hormone receptor (PTHR) regulates mineral-ion homeostasis and bone remodeling. Upon parathyroid hormone (PTH) stimulation, the PTHR internalizes into early endosomes and subsequently traffics to the retromer complex, a sorting platform on early endosomes that promotes recycling of surface receptors. The C terminus of the PTHR contains a type I PDZ ligand that binds PDZ domain-containing proteins. Mass spectrometry identified sorting nexin 27 (SNX27) in isolated endosomes as a PTHR binding partner. PTH treatment enriched endosomal PTHR. SNX27 contains a PDZ domain and serves as a cargo selector for the retromer complex. VPS26, VPS29, and VPS35 retromer subunits were isolated with PTHR in endosomes from cells stimulated with PTH. Molecular dynamics and protein binding studies establish that PTHR and SNX27 interactions depend on the PDZ recognition motif in PTHR and the PDZ domain of SNX27. Depletion of either SNX27 or VPS35 or actin depolymerization decreased the rate of PTHR recycling following agonist stimulation. Mutating the PDZ ligand of PTHR abolished the interaction with SNX27 but did not affect the overall rate of recycling, suggesting that PTHR may directly engage the retromer complex. Coimmunoprecipitation and overlay experiments show that both intact and mutated PTHR bind retromer through the VPS26 protomer and sequentially assemble a ternary complex with PTHR and SNX27. SNX27-independent recycling may involve N-ethylmaleimide-sensitive factor, which binds both PDZ intact and mutant PT