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Sample records for membrane progesterone receptor

  1. The Role of Progesterone and a Novel Progesterone Receptor, Progesterone Receptor Membrane Component 1, in the Inflammatory Response of Fetal Membranes to Ureaplasma parvum Infection.

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    Liping Feng

    Full Text Available Ureaplasma parvum (U. parvum is gaining recognition as an important pathogen for chorioamnionitis and preterm premature rupture of membranes. We aimed to investigate the roles of progesterone (P4 and a novel progesterone receptor, progesterone receptor membrane component 1 (PGRMC1, in the response of fetal membranes to U. parvum. Fetal membrane cells (amnion, chorion and decidua were isolated and confirmed to be free of Mycoplasmataceae. Cells were treated with U. parvum (5x106 CFU, and adherence was quantified by qPCR. Amnion and chorion cells were transfected with scrambled siRNA or validated PGRMC1 siRNA for 72h. Cells were then treated with U. parvum for 4h with or without pretreatment with P4 (10-7 M or ethanol for 1h. Interleukin-8 (IL-8, matrix metalloproteinase 9 (MMP9 and cyclooxygenase (COX-2 mRNA expression were quantified by qRT-PCR. Culture medium was harvested and analyzed for IL-8 and prostaglandin (PGE2 secretion by ELISA and MMP9 activity by zymography. U. parvum had a mean adherence of 15.0±0.6%, 16.9± 3.7% and 4.7±0.3% in cultured amnion, chorion and decidua cells, respectively. Exposure to U. parvum elicited significant inflammatory responses including induction of IL-8, COX-2, PGE2 and MMP9. A possible role of PGRMC1 was identified in the inhibition of U. parvum-stimulated COX-2 and MMP9 mRNA expression in chorion cells and MMP9 activity in amnion cells. On the other hand, it might enhance the U. parvum-stimulated IL-8 protein secretion in amnion cells. P4, mediated through PGRMC1, significantly inhibited U. Parvum-induced MMP9 mRNA and COX-2 mRNA expression in chorion cells. P4 appeared to attenuate U. parvum induced IL-8 mRNA expression in chorion cells, but this P4 effect might not mediated through PGRMC1. In summary, U. parvum preferentially adheres to and induces inflammatory responses in chorion and amnion cells. P4 and PGRMC1 appear to differentially modulate the inflammatory responses induced by U. parvum among

  2. Internalisation of membrane progesterone receptor-α after treatment with progesterone: Potential involvement of a clathrin-dependent pathway.

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    Foster, Helen; Reynolds, Alan; Stenbeck, Gudrun; Dong, Jing; Thomas, Peter; Karteris, Emmanouil

    2010-01-01

    Internalisation and recycling of seven trans-membrane domain receptors is a critical regulatory event for their signalling. The mechanism(s) by which membrane progesterone receptor-α (mPRα) number is regulated on the cell surface is unclear. In this study, we investigated the cellular distribution of mPRα and mechanisms of mPRα trafficking using a cell line derived from a primary culture of human myometrial cells (M11) as an experimental model. RT-PCR and immunofluorescent analysis demonstrated expression of mPRα in M11 cells with mPRα primarily distributed on the cell surface under basal conditions. For the first time, plasma membrane localisation of mPRα was confirmed using immuno-gold transmission electron microscopy. Stimulation of M11 cells with progesterone (P4, 100 nM) resulted in internalisation of mPRα from the plasma membrane to the cytoplasm (10 min) and subsequent partial translocation back to the cell surface (20 min). We investigated potential endocytotic pathways involved in trafficking of mPRα after its internalisation. Partial co-localisation of clathrin with mPRα was obvious after 10 min of P4 treatment. Of note, chlorpromazine (inhibitor of clathrin-mediated pathway) inhibited the endocytosis of mPRα, whereas treatment with nystatin (inhibitor of caveolae-mediated pathway) did not affect internalisation. Collectively, these data suggest that mPRα is expressed on the cell surface of M11 cells and undergoes endocytosis after P4 stimulation primarily via a clathrin-mediated pathway.

  3. Membrane progesterone receptor beta (mPRβ/Paqr8) promotes progesterone-dependent neurite outgrowth in PC12 neuronal cells via non-G protein-coupled receptor (GPCR) signaling.

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    Kasubuchi, Mayu; Watanabe, Keita; Hirano, Kanako; Inoue, Daisuke; Li, Xuan; Terasawa, Kazuya; Konishi, Morichika; Itoh, Nobuyuki; Kimura, Ikuo

    2017-07-12

    Recently, sex steroid membrane receptors garnered world-wide attention because they may be related to sex hormone-mediated unknown rapid non-genomic action that cannot be currently explained by their genomic action via nuclear receptors. Progesterone affects cell proliferation and survival via non-genomic effects. In this process, membrane progesterone receptors (mPRα, mPRβ, mPRγ, mPRδ, and mPRε) were identified as putative G protein-coupled receptors (GPCRs) for progesterone. However, the structure, intracellular signaling, and physiological functions of these progesterone receptors are still unclear. Here, we identify a molecular mechanism by which progesterone promotes neurite outgrowth through mPRβ (Paqr8) activation. Mouse mPRβ mRNA was specifically expressed in the central nervous system. It has an incomplete GPCR topology, presenting 6 transmembrane domains and did not exhibit typical GPCR signaling. Progesterone-dependent neurite outgrowth was exhibited by the promotion of ERK phosphorylation via mPRβ, but not via other progesterone receptors such as progesterone membrane receptor 1 (PGRMC-1) and nuclear progesterone receptor in nerve growth factor-induced neuronal PC12 cells. These findings provide new insights of regarding the non-genomic action of progesterone in the central nervous system.

  4. Membrane progesterone receptor beta (mPR?/Paqr8) promotes progesterone-dependent neurite outgrowth in PC12 neuronal cells via non-G protein-coupled receptor (GPCR) signaling

    OpenAIRE

    Kasubuchi, Mayu; Watanabe, Keita; Hirano, Kanako; Inoue, Daisuke; Li, Xuan; Terasawa, Kazuya; Konishi, Morichika; Itoh, Nobuyuki; Kimura, Ikuo

    2017-01-01

    Recently, sex steroid membrane receptors garnered world-wide attention because they may be related to sex hormone-mediated unknown rapid non-genomic action that cannot be currently explained by their genomic action via nuclear receptors. Progesterone affects cell proliferation and survival via non-genomic effects. In this process, membrane progesterone receptors (mPRα, mPRβ, mPRγ, mPRδ, and mPRε) were identified as putative G protein-coupled receptors (GPCRs) for progesterone. However, the st...

  5. Membrane progesterone receptor alpha as a potential prognostic biomarker for breast cancer survival: a retrospective study.

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    Mingxuan Xie

    Full Text Available Classically, the actions of progesterone (P4 are attributed to the binding of nuclear progesterone receptor (PR and subsequent activation of its downstream target genes. These mechanisms, however, are not applicable to PR- or basal phenotype breast cancer (BPBC due to lack of PR in these cancers. Recently, the function of membrane progesterone receptor alpha (mPRα in human BPBC cell lines was studied in our lab. We proposed that the signaling cascades of P4→mPRα pathway may play an essential role in controlling cell proliferation and epithelial mesenchymal transition (EMT of breast cancer. Using human breast cancer tissue microarrays, we found in this study that the average intensity of mPRα expression, but not percentage of breast cancer with high level of mPRα expression (mPRα-HiEx, was significantly lower in the TNM stage 4 patients compared to those with TNM 1-3 patients; and both average intensities of mPRα expression and mPRα-HiEx rates were significantly higher in cancers negative for ER, as compared with those cancers with ER+. However, after adjusting for age at diagnosis and/or TNM stage, only average intensities of mPRα expression were associated with ER status. In addition, we found that the rates of mPRα-HiEx were significantly higher in cancers with epithelial growth factor receptor-1 (EGFR+ and high level of Ki67 expression, indicating positive correlation between mPRα over expression and EGFR or Ki67. Further analysis indicated that both mPRα-HiEx rate and average intensity of mPRα expression were significantly higher in HER2+ subtype cancers (i.e. HER2+ER-PR- as compared to ER+ subtype cancers. These data support our hypothesis that P4 modulates the activities of the PI3K and cell proliferation pathways through the caveolar membrane bound growth factor receptors such as mPRα and growth factor receptors. Future large longitudinal studies with larger sample size and survival outcomes are necessary to confirm our

  6. Characterization and ligand identification of a membrane progesterone receptor in fungi: existence of a novel PAQR in Sporothrix schenckii.

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    Gonzalez-Velazquez, Waleska; Gonzalez-Mendez, Ricardo; Rodriguez-del Valle, Nuri

    2012-09-07

    Adaptive responses in fungi result from the interaction of membrane receptors and extracellular ligands. Many different classes of receptors have been described in eukaryotic cells. Recently a new family of receptors classified as belonging to the progesterone-adiponectin receptor (PAQR) family has been identified. These receptors have the seven transmembrane domains characteristic of G-protein coupled receptors, but their activity has not been associated directly to G proteins. They share sequence similarity to the eubacterial hemolysin III proteins. A new receptor, SsPAQR1 (Sporothrix schenckii progesterone-adiponectinQ receptor1), was identified as interacting with Sporothrix schenckii G protein alpha subunit SSG-2 in a yeast two-hybrid assay. The receptor was identified as a member of the PAQR family. The cDNA sequence revealed a predicted ORF of 1542 bp encoding a 514 amino acids protein with a calculated molecular weight of 57.8 kDa. Protein domain analysis of SsPAQR1 showed the 7 transmembrane domains (TM) characteristic of G protein coupled receptors and the presence of the distinctive motifs that characterize PAQRs. A yeast-based assay specific for PAQRs identified progesterone as the agonist. S. schenckii yeast cells exposed to progesterone (0.50 mM) showed an increase in intracellular levels of 3', 5' cyclic adenosine monophosphate (cAMP) within the first min of incubation with the hormone. Different progesterone concentrations were tested for their effect on the growth of the fungus. Cultures incubated at 35°C did not grow at concentrations of progesterone of 0.05 mM or higher. Cultures incubated at 25°C grew at all concentrations tested (0.01 mM-0.50 mM) with growth decreasing gradually with the increase in progesterone concentration. This work describes a receptor associated with a G protein alpha subunit in S. schenckii belonging to the PAQR family. Progesterone was identified as the ligand. Exposure to progesterone increased the levels of cAMP in

  7. Cloning and initial characterization of nuclear and membrane progesterone receptors in the Fathead Minnow, Pimephales promelas

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    Both native progestagens and synthetic progestins have important effects on reproduction that are mediated through progesterone receptors (PRs). They regulate gamete maturation and can serve as precursors for other steroid hormones in vertebrates and act as reproductive pheromone...

  8. The Sigma-2 Receptor and Progesterone Receptor Membrane Component 1 are Different Binding Sites Derived From Independent Genes

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    Uyen B. Chu

    2015-11-01

    Full Text Available The sigma-2 receptor (S2R is a potential therapeutic target for cancer and neuronal diseases. However, the identity of the S2R has remained a matter of debate. Historically, the S2R has been defined as (1 a binding site with high affinity to 1,3-di-o-tolylguanidine (DTG and haloperidol but not to the selective sigma-1 receptor ligand (+-pentazocine, and (2 a protein of 18–21 kDa, as shown by specific photolabeling with [3H]-Azido-DTG and [125I]-iodoazido-fenpropimorph ([125I]-IAF. Recently, the progesterone receptor membrane component 1 (PGRMC1, a 25 kDa protein, was reported to be the S2R (Nature Communications, 2011, 2:380. To confirm this identification, we created PGRMC1 knockout NSC34 cell lines using the CRISPR/Cas9 technology. We found that in NSC34 cells devoid of or overexpressing PGRMC1, the maximum [3H]-DTG binding to the S2R (Bmax as well as the DTG-protectable [125I]-IAF photolabeling of the S2R were similar to those of wild-type control cells. Furthermore, the affinities of DTG and haloperidol for PGRMC1 (KI = 472 μM and 350 μM, respectively, as determined in competition with [3H]-progesterone, were more than 3 orders of magnitude lower than those reported for the S2R (20–80 nM. These results clarify that PGRMC1 and the S2R are distinct binding sites expressed by different genes.

  9. Cloning and initial characterization of nuclear and four membrane progesterone receptors in the fathead minnow(Pimephales promelas)

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    Both native progestagens and synthetic progestins have important effects on reproduction that are mediated through progesterone receptors (PRs). Progestagens regulate gamete maturation in vertebrates, are critical regulators of placental mammal pregnancy, and act as reproductive ...

  10. Two unrelated putative membrane-bound progestin receptors, progesterone membrane receptor component 1 (PGMRC1 and membrane progestin receptor (mPR beta, are expressed in the rainbow trout oocyte and exhibit similar ovarian expression patterns

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    Fostier Alexis

    2006-02-01

    Full Text Available Abstract Background In lower vertebrates, steroid-induced oocyte maturation is considered to involve membrane-bound progestin receptors. Two totally distinct classes of putative membrane-bound progestin receptors have been reported in vertebrates. A first class of receptors, now termed progesterone membrane receptor component (PGMRC; subtypes 1 and 2 has been studied since 1996 but never studied in a fish species nor in the oocyte of any animal species. A second class of receptors, termed membrane progestin receptors (mPR; subtypes alpha, beta and gamma, was recently described in vertebrates and implicated in the progestin-initiated induction of oocyte maturation in fish. Methods In the present study, we report the characterization of the full coding sequence of rainbow trout PGMRC1 and mPR beta cDNAs, their tissue distribution, their ovarian expression profiles during oogenesis, their hormonal regulation in the full grown ovary and the in situ localization of PGMRC1 mRNA in the ovary. Results Our results clearly show, for the first time in any animal species, that rainbow trout PGMRC1 mRNA is present in the oocyte and has a strong expression in ovarian tissue. In addition, we show that both mPR beta and PGMRC1, two members of distinct membrane-bound progestin receptor classes, exhibit highly similar ovarian expression profiles during the reproductive cycle with maximum levels during vitellogenesis and a down-expression during late vitellogenesis. In addition, the mRNA abundance of both genes is not increased after in vitro hormonal stimulation of full grown follicles by maturation inducing hormones. Conclusion Together, our findings suggest that PGMRC1 is a new possible participant in the progestin-induced oocyte maturation in fish. However, its participation in the process of oocyte maturation, which remains to be confirmed, would occur at post-transcriptional levels.

  11. Progesterone Receptor Subcellular Localization and Gene Expression Profile in Human Astrocytoma Cells Are Modified by Progesterone

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    Aliesha González-Arenas

    2014-11-01

    Full Text Available Intracellular progesterone receptor (PR has been identified in human astrocytomas, the most common and aggressive primary brain tumors in humans. It has been reported that PR cell distribution affects their transcriptional activity and turnover. In this work we studied by immunofluorescence the effects of estradiol and progesterone on the subcellular localization of PR in a grade III human astrocytoma derived cell line (U373. We observed that total PR was mainly distributed in the cytoplasm without hormonal treatment. Estradiol (10 nM increased PR presence in the cytoplasm of U373 cells, whereas progesterone (10 nM and RU486 (PR antagonist, 1 μM blocked this effect. To investigate the role of PR activity in the regulation of gene expression pattern of U373 cells, we evaluated by microarray analysis the profile of genes regulated by progesterone, RU486, or both steroids. We found different genes regulated by steroid treatments that encode for proteins involved in metabolism, transport, cell cycle, proliferation, metastasis, apoptosis, processing of nucleic acids and proteins, adhesion, pathogenesis, immune response, cytoskeleton, and membrane receptors. We determined that 30 genes were regulated by progesterone, 41 genes by RU486 alone, and 13 genes by the cotreatment of progesterone+RU486, suggesting that there are many genes regulated by intracellular PR or through other signaling pathways modulated by progesterone. All these data suggest that PR distribution and activity should modify astrocytomas growth.

  12. The presence of a membrane-bound progesterone receptor sensitizes the estradiol-induced effect on the proliferation of human breast cancer cells.

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    Neubauer, Hans; Yang, Yang; Seeger, Harald; Fehm, Tanja; Cahill, Michael A; Tong, Xiaowen; Ruan, Xiangyan; Mueck, Alfred O

    2011-08-01

    Breast cancer risk is still an important topic regarding hormone therapy as well as oral contraception. Evidence that progestogens may play a crucial role is accumulating. Progesterone receptor membrane component 1 (PGRMC1) expressed in breast cancer may be important in tumorigenesis and thus may increase breast cancer risk. The aim of this project was to investigate the influence of different estradiol (E2) concentrations and the addition of two progestogens on MCF-7 breast cancer cells overexpressing PGRMC1. MCF-7 cells were stably transfected with PGRMC1 expression plasmid (MCF-7/PGRMC1-3HA [WT-12]). To test the effects of E2 and progestogens on cell proliferation, MCF-7 and WT-12 cells were stimulated with different concentrations of E2 (10 and 10 M) alone and in combination with progesterone and medroxyprogesterone acetate (each 10 M). E2 elicited a concentration-dependent proliferative effect on both cell lines, which was much more pronounced in WT-12 cells (50% vs 200%). This effect could be completely abrogated by the addition of the E2 antagonist fulvestrant. Addition of progesterone had no influence on the E2-induced effect, whereas medroxy-progesterone acetate enhanced the E2-induced effect at a low E2 concentration, which was, again, more pronounced in the WT-12 cells. The figures were between 20% and 40% in MCF-7 and between 60% and 250% in WT-12 cells. Overexpression of PGRMC1 sensitizes the proliferative response of the MCF-7 breast cancer cell line to estradiol. The effect of progestogens on breast cancer tumorigenesis may depend on the specific progestogen used for hormone therapy or oral contraception.

  13. Expression of progesterone receptor membrane component-2 within the immature rat ovary and its role in regulating mitosis and apoptosis of spontaneously immortalized granulosa cells.

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    Griffin, Daniel; Liu, Xiufang; Pru, Cindy; Pru, James K; Peluso, John J

    2014-08-01

    Progesterone receptor membrane component 2 (Pgrmc2) mRNA was detected in the immature rat ovary. By 48 h after eCG, Pgrmc2 mRNA levels decreased by 40% and were maintained at 48 h post-hCG. Immunohistochemical studies detected PGRMC2 in oocytes and ovarian surface epithelial, interstitial, thecal, granulosa, and luteal cells. PGRMC2 was also present in spontaneously immortalized granulosa cells, localizing to the cytoplasm of interphase cells and apparently to the mitotic spindle of cells in metaphase. Interestingly, PGRMC2 levels appeared to decrease during the G1 stage of the cell cycle. Moreover, overexpression of PGRMC2 suppressed entry into the cell cycle, possibly by binding the p58 form of cyclin dependent kinase 11b. Conversely, Pgrmc2 small interfering RNA (siRNA) treatment increased the percentage of cells in G1 and M stage but did not increase the number of cells, which was likely due to an increase in apoptosis. Depleting PGRMC2 did not inhibit cellular (3)H-progesterone binding, but attenuated the ability of progesterone to suppress mitosis and apoptosis. Taken together these studies suggest that PGRMC2 affects granulosa cell mitosis by acting at two specific stages of the cell cycle. First, PGRMC2 regulates the progression from the G0 into the G1 stage of the cell cycle. Second, PGRMC2 appears to localize to the mitotic spindle, where it likely promotes the final stages of mitosis. Finally, siRNA knockdown studies indicate that PGRMC2 is required for progesterone to slow the rate of granulosa cell mitosis and apoptosis. These findings support a role for PGRMC2 in ovarian follicle development. © 2014 by the Society for the Study of Reproduction, Inc.

  14. Progesterone Receptor Scaffolding Function in Breast Cancer

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    2012-10-01

    response. PR are expressed in multiple human tissues including the uterus, mammary gland , brain, pancreas, thymus , bone, ovary, testes, and in the...ABSTRACT Progesterone receptors (PR) are critical mediators of mammary gland development and contribute to breast cancer progression. Progestin...receptors (PR) are critical for massive breast epithelial cell expansion during mammary gland development and contribute to breast cancer progression

  15. Progesterone receptor modulators in breast cancer

    OpenAIRE

    WIEHLE, Ronald D.

    2015-01-01

    Breast cancer has been treated successfully with selective estrogen receptor antagonists (SERMs) such as tamoxifen, receptor-depleting agents such as fulvestrant, and aromatase inhibitors such as anastrozole. Selective progesterone receptor modulators (SPRMs or PRMs) have not been studied as much and are currently under investigation for inhibition of mammary carcinogenesis in animal models and breast cancer prevention trials in women. They might follow tamoxifen and aromatase inhibitors in t...

  16. Progesterone receptor modulators for endometriosis.

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    Fu, Jing; Song, Hao; Zhou, Min; Zhu, Huili; Wang, Yuhe; Chen, Hengxi; Huang, Wei

    2017-07-25

    Endometriosis is defined as the presence of endometrial tissue (glands and stroma) outside the uterine cavity. This condition is oestrogen-dependent and thus is seen primarily during the reproductive years. Owing to their antiproliferative effects in the endometrium, progesterone receptor modulators (PRMs) have been advocated for treatment of endometriosis. To assess the effectiveness and safety of PRMs primarily in terms of pain relief as compared with other treatments or placebo or no treatment in women of reproductive age with endometriosis. We searched the following electronic databases, trial registers, and websites: the Cochrane Gynaecology and Fertility Group (CGFG) Specialised Register of Controlled Trials, the Central Register of Studies Online (CRSO), MEDLINE, Embase, PsycINFO, clinicaltrials.gov, and the World Health Organization (WHO) platform, from inception to 28 November 2016. We handsearched reference lists of articles retrieved by the search. We included randomised controlled trials (RCTs) published in all languages that examined effects of PRMs for treatment of symptomatic endometriosis. We used standard methodological procedures as expected by the Cochrane Collaboration. Primary outcomes included measures of pain and side effects. We included 10 randomised controlled trials (RCTs) with 960 women. Two RCTs compared mifepristone versus placebo or versus a different dose of mifepristone, one RCT compared asoprisnil versus placebo, one compared ulipristal versus leuprolide acetate, and four compared gestrinone versus danazol, gonadotropin-releasing hormone (GnRH) analogues, or a different dose of gestrinone. The quality of evidence ranged from high to very low. The main limitations were serious risk of bias (associated with poor reporting of methods and high or unclear rates of attrition in most studies), very serious imprecision (associated with low event rates and wide confidence intervals), and indirectness (outcome assessed in a select subgroup

  17. Expression of Estrogen and Progesterone Receptors among ...

    African Journals Online (AJOL)

    Study design: This is a descriptive study to detect the level of Estrogen (ER) and Progesterone (PR) receptors in a sample of biopsies from Sudanese women with breast cancer presented at Khartoum teaching Hospital Material and Methods: Forty biopsies from breast cancer patients were examined with immunostaining

  18. Progesterone receptor levels independently predict survival in endometrial adenocarcinoma

    DEFF Research Database (Denmark)

    Nyholm, H C; Christensen, Ib Jarle; Nielsen, Anette Lynge

    1995-01-01

    Estrogen receptor (ER) and progesterone receptor (PR) contents were determined by biochemical (dextran charcoal-coated (DCC) assay) and immunohistochemical (ICA) methods in biopsies from 145 primary endometrial adenocarcinomas and those with eligible receptor measurements were analyzed with respect...

  19. Expression and localization of progesterone receptor membrane component 1 and 2 and serpine mRNA binding protein 1 in the bovine corpus luteum during the estrous cycle and the first trimester of pregnancy.

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    Kowalik, Magdalena K; Rekawiecki, Robert; Kotwica, Jan

    2014-11-01

    The aim of this study was to evaluate the mRNA and protein expression and the localization of progesterone receptor membrane component 1 (PGRMC1), PGRMC2, and the PGRMC1 partner serpine mRNA binding protein 1 (SERBP1) in the bovine CL on Days 2 to 5, 6 to 10, 11 to 16, and 17 to 20 of the estrous cycle as well as during Weeks 3 to 5, 6 to 8, and 9 to 12 of pregnancy (n = 5-6 per each period). The highest levels of PGRMC1 and PGRMC2 mRNA expression were found on Days 6 to 16 (P cycle and during pregnancy (P cycle compared with the other stages of the estrous cycle and pregnancy, whereas PGRMC2 protein expression (P cycle and was at its lowest (P cows, the patterns of SERBP1 mRNA and protein expression remained constant and were comparable with those observed during the estrous cycle. Progesterone receptor membrane component 1 and PGRMC2 localized to both large and small luteal cells, whereas SERBP1 was observed mainly in small luteal cells and much less frequently in large luteal cells. All proteins were also localized in the endothelial cells of blood vessels. The data obtained indicate the variable expression of PGRMC1, PGRMC2, and SERBP1 mRNA and protein in the bovine CL and suggest that progesterone may regulate CL function via its membrane receptors during both the estrous cycle and pregnancy. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Progesterone receptor membrane component 1 inhibits the activity of drug-metabolizing cytochromes P450 and binds to cytochrome P450 reductase.

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    Szczesna-Skorupa, Elzbieta; Kemper, Byron

    2011-03-01

    Progesterone receptor membrane component 1 (PGRMC1) has been shown to interact with several cytochromes P450 (P450s) and to activate enzymatic activity of P450s involved in sterol biosynthesis. We analyzed the interactions of PGRMC1 with the drug-metabolizing P450s, CYP2C2, CYP2C8, and CYP3A4, in transfected cells. Based on coimmunoprecipitation assays, PGRMC1 bound efficiently to all three P450s, and binding to the catalytic cytoplasmic domain of CYP2C2 was much more efficient than to a chimera containing only the N-terminal transmembrane domain. Down-regulation of PGRMC1 expression levels in human embryonic kidney 293 and HepG2 cell lines stably expressing PGRMC1-specific small interfering RNA had no effect on the endoplasmic reticulum localization and expression levels of P450s, whereas enzymatic activities of CYP2C2, CYP2C8, and CYP3A4 were slightly higher in PGRMC1-deficient cells. Cotransfection of cells with P450s and PGRMC1 resulted in PGRMC1 concentration-dependent inhibition of the P450 activities, and this inhibition was partially reversed by increased expression of the P450 reductase (CPR). In contrast, CYP51 activity was decreased by down-regulation of PGRMC1 and expression of PGRMC1 in the PGRMC1-deficient cells increased CYP51 activity. In cells cotransfected with CPR and PGRMC1, strong binding of CPR to PGRMC1 was observed; however, in the presence of CYP2C2, interaction of PGRMC1 with CPR was significantly reduced, suggesting that CYP2C2 competes with CPR for binding to PGRMC1. These data show that in contrast to sterol synthesizing P450, PGRMC1 is not required for the activities of several drug-metabolizing P450s, and its overexpression inhibits those P450 activities. Furthermore, PGRMC1 binds to CPR, which may influence P450 activity.

  1. Oxidative stress effect on progesterone-induced blocking factor (PIBF) binding to PIBF-receptor in lymphocytes.

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    de la Haba, Carlos; Palacio, José R; Palkovics, Tamas; Szekeres-Barthó, Júlia; Morros, Antoni; Martínez, Paz

    2014-01-01

    Receptor-ligand binding is an essential interaction for biological function. Oxidative stress can modify receptors and/or membrane lipid dynamics, thus altering cell physiological functions. The aim of this study is to analyze how oxidative stress may alter receptor-ligand binding and lipid domain distribution in the case of progesterone-induced blocking factor/progesterone-induced blocking factor-receptor. For membrane fluidity regionalization analysis of MEC-1 lymphocytes, two-photon microscopy was used in individual living cells. Lymphocytes were also double stained with AlexaFluor647/progesterone-induced blocking factor and Laurdan to evaluate -induced blocking factor/progesterone-induced blocking factor-receptor distribution in the different membrane domains, under oxidative stress. A new procedure has been developed which quantitatively analyzes the regionalization of a membrane receptor among the lipid domains of different fluidity in the plasma membrane. We have been able to establish a new tool which detects and evaluates lipid raft clustering from two-photon microscopy images of individual living cells. We show that binding of progesterone-induced blocking factor to progesterone-induced blocking factor-receptor causes a rigidification of plasma membrane which is related to an increase of lipid raft clustering. However, this clustering is inhibited under oxidative stress conditions. In conclusion, oxidative stress decreases membrane fluidity, impairs receptor-ligand binding and reduces lipid raft clustering. © 2013.

  2. Progesterone receptor and dopamine receptors are required in Δ9-tetrahydrocannabinol modulation of sexual receptivity in female rats

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    Mani, Shailaja K.; Mitchell, Andrea; O'Malley, Bert W.

    2001-01-01

    Ovarian steroids, estrogen and progesterone, influence the sensitivity of certain neural processes to cannabinoid treatment by modulation of brain dopaminergic activity. We examined the effects of the active ingredient of cannabis, Δ9-tetrahydrocannabinol (THC), on sexual behavior in female rats and its influence on steroid hormone receptors and neurotransmitters in the facilitation of sexual receptivity. Our results revealed that the facilitatory effect of THC was inhibited by antagonists to both progesterone and dopamine D1 receptors. To test further the idea that progesterone receptors (PR) and/or dopamine receptors (D1R) in the hypothalamus are required for THC-facilitated sexual behavior in rodents, antisense and sense oligonucleotides to PR and D1R were administered intracerebroventricularly (ICV) into the third cerebral ventricle of ovariectomized, estradiol benzoate-primed rats. Progesterone- and THC-facilitated sexual behavior was inhibited in animals treated with antisense oligonucleotides to PR or to D1R. Antagonists to cannabinoid receptor-1 subtype (CB1), but not to cannabinoid receptor-2 subtype (CB2) inhibited progesterone- and dopamine-facilitated sexual receptivity in female rats. Our studies indicate that THC acts on the CB1 cannabinoid receptor to initiate a signal transduction response that requires both membrane dopamine and intracellular progesterone receptors for effective induction of sexual behavior. PMID:11158625

  3. Contraceptive applications of progesterone receptor modulators.

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    Chabbert-Buffet, Nathalie; Ouzounian, Sophie; Kairis, Axelle Pintiaux; Bouchard, Philippe

    2008-09-01

    Currently developed progesterone receptor modulators (PRMs) are steroid-derived compounds with mild or potent antiprogestin activity. PRMs may exert a contraceptive activity by different mechanisms such as blockade of ovulation and endometrial desynchronization. Their potential clinical applications are manifold and are very promising in major public health areas, including emergency contraception, long term oestrogen-free contraception (administered alone, or in association with a progestin-only pill to improve bleeding patterns), endometriosis and myoma treatment. The mechanisms of their anti-ovulatory effects and of the endometrial modifications elicited during long term PRM treatment are still not fully elucidated. In future clinical applications, PRMs will be administered orally, via intrauterine systems or vaginal rings.

  4. Molecular profiles of progesterone receptor loss in human breast tumors

    NARCIS (Netherlands)

    Creighton, Chad J.; Kent Osborne, C.; van de Vijver, Marc J.; Foekens, John A.; Klijn, Jan G.; Horlings, Hugo M.; Nuyten, Dimitry; Wang, Yixin; Zhang, Yi; Chamness, Gary C.; Hilsenbeck, Susan G.; Lee, Adrian V.; Schiff, Rachel

    2009-01-01

    Background Patient prognosis and response to endocrine therapy in breast cancer correlate with protein expression of both estrogen receptor (ER) and progesterone receptor (PR), with poorer outcome in patients with ER+/PR- compared to ER+/PR+ tumors. Methods To better understand the underlying

  5. Cellular progesterone receptor phosphorylation in response to ligands activating protein kinases

    Energy Technology Data Exchange (ETDEWEB)

    Rao, K.V.; Peralta, W.D.; Greene, G.L.; Fox, C.F.

    1987-08-14

    Progesterone receptors were immunoprecipitated with monoclonal antibodies KD68 from lysates of human breast carcinoma T47D cells labelled to steady state specific activity with /sup 32/Pi. The 120 kDa /sup 32/P-labelled progesterone receptor band was resolved by polyacrylamide gel electrophoresis and identified by autoradiography. Phosphoamino acid analysis revealed serine phosphorylation, but no threonine or tyrosine phosphorylation. Treatment of the /sup 32/Pi-labelled cells with EGF, TPA or dibutyryl cAMP had no significant quantitative effect on progesterone receptor phosphorylation, though the EGF receptor and the cAMP-dependent protein kinases have been reported to catalyze phosphorylation of purified avian progesterone receptor preparations in cell free systems. Progesterone receptor phosphorylation on serine residues was increased by 2-fold in cells treated with 10 nM progesterone; EGF had no effect on progesterone-mediated progesterone receptor phosphorylation.

  6. Progesterone arrested cell cycle progression through progesterone receptor isoform A in pancreatic neuroendocrine neoplasm.

    Science.gov (United States)

    Yazdani, Samaneh; Kasajima, Atsuko; Onodera, Yoshiaki; McNamara, Keely May; Ise, Kazue; Nakamura, Yasuhiro; Tachibana, Tomoyoshi; Motoi, Fuyuhiko; Unno, Michiaki; Sasano, Hironobu

    2018-04-01

    In pancreatic neuroendocrine neoplasms (Pan-NEN) progesterone signaling has been shown to have both inhibitory and stimulatory effects on cell proliferation. The ability of progesterone to inhibit tumor proliferation is of particular interest and is suggested to be mediated through the less abundantly expressed progesterone receptor (PR) isoform A (PRA). To date the mechanistic processes underlying this inhibition of proliferation remain unclear. To examine the mechanism of PRA actions, the human Pan-NEN cell line QGP-1, that endogenously expresses PR isoform B (PRB) without PRA, was transfected with PRA. PRA transfection suppressed the majority of cell cycle related genes increased by progesterone including cyclin A2 (CCNA2), cyclin B1 (CCNB1), cyclin-dependent kinase 1 (CDK1) and cyclin-dependent kinase 2 (CDK2). Importantly, following progesterone administration cell cycle distribution was shifted to S and G2/M phases in the naïve cell line but in PRA-transfected cells, this effect was suppressed. To see if these mechanistic insights were confirmed in patient samples PRA, PRB, CCNA2, CCNB, CDK1 and CDK2 immunoreactivities were assessed in Pan-NEN cases. Higher levels of cell cycle markers were associated with higher WHO grade tumors and correlations between the markers suggested formation of cyclin/CDK activated complexes in S and G2/M phases. PRA expression was associated with inverse correlation of all cell cycle markers. Collectively, these results indicate that progesterone signals through PRA negatively regulates cell cycle progression through suppressing S and G2/M phases and downregulation of cell cycle phases specific cyclins/CDKs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Immunohistochemical Expression of Estrogen and Progesterone Receptors in Epulis Fissuratum

    Directory of Open Access Journals (Sweden)

    Maryam Seyedmajidi

    2013-01-01

    Full Text Available Background: Epulis Fissuratum (Epulis Fissuratum (EF or Denture Epulis or inflammatory fibrous hyperplasia is a common hyperplastic tumor-like lesion with reactive nature, related to loose and ill-fitting, full or partial removable dentures and it is more common in women than men. For this reason, hormonal influences may also play role in its creation. The effect of steroid hormones especially sex hormones (Estrogen and progesterone on oral mucosa is identified in some studies. In the present study, the distribution pattern and presence of estrogen and progesterone receptors in epithelial, stromal, endothelial and inflammatory cells in Epulis Fissuratum was investigated. Materials and Methods: This cross-sectional study was carried out on 30 samples of paraffin blocks with Epulis Fissuratum diagnosis and 30 samples of normal mucosal tissues as a control group who have had surgery as a margin beside the above lesions and had been obtained from the oral and maxillofacial pathology departement of Babol Dental School since 2003 up to 2010. Intensity of staining and immunoreactivity were evaluated using subjective index and considering the positive control group (breast carcinoma.Results: Epithelial, stromal, endothelial and inflammatory cells didn’t show reaction with monoclonal antibodies against estrogen and progesterone in none of the samples. Conclusion: It seems that the hypothesis of the existence of estrogen and progesterone receptors in epulis fissuratum and normal oral mucosa is ruled out. The possibility of direct effect of estrogen and progesterone in occurring of epulis fissuratum is rejected.

  8. Immunohistochemical assessment of oestrogen and progesterone receptors

    DEFF Research Database (Denmark)

    Grabau, D A; Thorpe, S M; Knoop, A

    2000-01-01

    Two different methods to determine steroid receptors were analysed with respect to their ability to estimate prognosis in primary breast cancer patients. The immunohistochemical assay (IHA) was compared with the dextran-coated charcoal (DCC) method of receptor determination. A random sample of 281...

  9. Improving the developability profile of pyrrolidine progesterone receptor partial agonists

    Energy Technology Data Exchange (ETDEWEB)

    Kallander, Lara S.; Washburn, David G.; Hoang, Tram H.; Frazee, James S.; Stoy, Patrick; Johnson, Latisha; Lu, Qing; Hammond, Marlys; Barton, Linda S.; Patterson, Jaclyn R.; Azzarano, Leonard M.; Nagilla, Rakesh; Madauss, Kevin P.; Williams, Shawn P.; Stewart, Eugene L.; Duraiswami, Chaya; Grygielko, Eugene T.; Xu, Xiaoping; Laping, Nicholas J.; Bray, Jeffrey D.; Thompson, Scott K. (GSKPA)

    2010-09-17

    The previously reported pyrrolidine class of progesterone receptor partial agonists demonstrated excellent potency but suffered from serious liabilities including hERG blockade and high volume of distribution in the rat. The basic pyrrolidine amine was intentionally converted to a sulfonamide, carbamate, or amide to address these liabilities. The evaluation of the degree of partial agonism for these non-basic pyrrolidine derivatives and demonstration of their efficacy in an in vivo model of endometriosis is disclosed herein.

  10. TRPV1 channels and the progesterone receptor Sig-1R interact to regulate pain.

    Science.gov (United States)

    Ortíz-Rentería, Miguel; Juárez-Contreras, Rebeca; González-Ramírez, Ricardo; Islas, León D; Sierra-Ramírez, Félix; Llorente, Itzel; Simon, Sidney A; Hiriart, Marcia; Rosenbaum, Tamara; Morales-Lázaro, Sara L

    2018-02-13

    The Transient Receptor Potential Vanilloid 1 (TRPV1) ion channel is expressed in nociceptors where, when activated by chemical or thermal stimuli, it functions as an important transducer of painful and itch-related stimuli. Although the interaction of TRPV1 with proteins that regulate its function has been previously explored, their modulation by chaperones has not been elucidated, as is the case for other mammalian TRP channels. Here we show that TRPV1 physically interacts with the Sigma 1 Receptor (Sig-1R), a chaperone that binds progesterone, an antagonist of Sig-1R and an important neurosteroid associated to the modulation of pain. Antagonism of Sig-1R by progesterone results in the down-regulation of TRPV1 expression in the plasma membrane of sensory neurons and, consequently, a decrease in capsaicin-induced nociceptive responses. This is observed both in males treated with a synthetic antagonist of Sig-1R and in pregnant females where progesterone levels are elevated. This constitutes a previously undescribed mechanism by which TRPV1-dependent nociception and pain can be regulated.

  11. Validation of kinetic modeling of progesterone release from polymeric membranes

    Directory of Open Access Journals (Sweden)

    Analia Irma Romero

    2018-01-01

    Full Text Available Mathematical modeling in drug release systems is fundamental in development and optimization of these systems, since it allows to predict drug release rates and to elucidate the physical transport mechanisms involved. In this paper we validate a novel mathematical model that describes progesterone (Prg controlled release from poly-3-hydroxybutyric acid (PHB membranes. A statistical analysis was conducted to compare the fitting of our model with six different models and the Akaike information criterion (AIC was used to find the equation with best-fit. A simple relation between mass and drug released rate was found, which allows predicting the effect of Prg loads on the release behavior. Our proposed model was the one with minimum AIC value, and therefore it was the one that statistically fitted better the experimental data obtained for all the Prg loads tested. Furthermore, the initial release rate was calculated and therefore, the interface mass transfer coefficient estimated and the equilibrium distribution constant of Prg between the PHB and the release medium was also determined. The results lead us to conclude that our proposed model is the one which best fits the experimental data and can be successfully used to describe Prg drug release in PHB membranes.

  12. Estrogen and progesterone receptors in endometrial carcinoma: comparison of immunohistochemical and biochemical analysis

    DEFF Research Database (Denmark)

    Nyholm, H C; Nielsen, Anette Lynge; Lyndrup, J

    1993-01-01

    In 159 endometrial carcinomas, estrogen (ER) and progesterone receptors (PR) were determined biochemically by dextran-coated charcoal (DCC) assay and immunohistochemically (ICA) on frozen sections. ICA receptor content was estimated by a total histologic score (HSCORE), including all tissue...

  13. Expression of Oestrogen and progesterone receptors, Ki-67,p53 and ...

    African Journals Online (AJOL)

    Expression of Oestrogen and progesterone receptors, Ki-67,p53 and bcl-2 proteins, cathepsin D, urokinase plasminogen activator and urokinase plasminogen activator-receptors in carcinomas of the female breast in an African population.

  14. Inverse Relationship between Progesterone Receptor and Myc in Endometrial Cancer.

    Directory of Open Access Journals (Sweden)

    Tamar Kavlashvili

    Full Text Available Endometrial cancer, the most common gynecologic malignancy, is a hormonally-regulated disease. Response to progestin therapy positively correlates with hormone receptor expression, in particular progesterone receptor (PR. However, many advanced tumors lose PR expression. We recently reported that the efficacy of progestin therapy can be significantly enhanced by combining progestin with epigenetic modulators, which we term "molecularly enhanced progestin therapy." What remained unclear was the mechanism of action and if estrogen receptor α (ERα, the principle inducer of PR, is necessary to restore functional expression of PR via molecularly enhanced progestin therapy. Therefore, we modeled advanced endometrial tumors that have lost both ERα and PR expression by generating ERα-null endometrial cancer cell lines. CRISPR-Cas9 technology was used to delete ERα at the genomic level. Our data demonstrate that treatment with a histone deacetylase inhibitor (HDACi was sufficient to restore functional PR expression, even in cells devoid of ERα. Our studies also revealed that HDACi treatment results in marked downregulation of the oncogene Myc. We established that PR is a negative transcriptional regulator of Myc in endometrial cancer in the presence or absence of ERα, which is in contrast to studies in breast cancer cells. First, estrogen stimulation augmented PR expression and decreased Myc in endometrial cancer cell lines. Second, progesterone increased PR activity yet blunted Myc mRNA and protein expression. Finally, overexpression of PR by adenoviral transduction in ERα-null endometrial cancer cells significantly decreased expression of Myc and Myc-regulated genes. Analysis of the Cancer Genome Atlas (TCGA database of endometrial tumors identified an inverse correlation between PR and Myc mRNA levels, with a corresponding inverse correlation between PR and Myc downstream transcriptional targets SRD5A1, CDK2 and CCNB1. Together, these data

  15. Progesterone receptor antagonist CDB-4124 increases depression-like behavior in mice without affecting locomotor ability

    Science.gov (United States)

    Beckley, Ethan H.; Scibelli, Angela C.; Finn, Deborah A.

    2010-01-01

    Progesterone withdrawal has been proposed as an underlying factor in premenstrual syndrome and postpartum depression. Progesterone withdrawal induces forced swim test (FST) immobility in mice, a depression-like behavior, but the contribution of specific receptors to this effect is unclear. The role of progesterone’s GABAA receptor-modulating metabolite allopregnanolone in depression- and anxiety-related behaviors has been extensively documented, but little attention has been paid to the role of progesterone receptors. We administered the classic progesterone receptor antagonist mifepristone (RU-38486) and the specific progesterone receptor antagonist CDB-4124 to mice that had been primed with progesterone for five days, and found that both compounds induced FST immobility reliably, robustly, and in a dose-dependent fashion. Although CDB-4124 increased FST immobility, it did not suppress initial activity in a locomotor test. These findings suggest that decreased progesterone receptor activity contributes to depression-like behavior in mice, consistent with the hypothesis that progesterone withdrawal may contribute to the symptoms of premenstrual syndrome or postpartum depression. PMID:21163582

  16. Microarray-Based Determination of Estrogen Receptor, Progesterone Receptor, and HER2 Receptor Status in Breast Cancer

    NARCIS (Netherlands)

    Roepman, Paul; Horlings, Hugo M.; Krijgsman, Oscar; Kok, Marleen; Bueno-de-Mesquita, Jolien M.; Bender, Richard; Linn, Sabine C.; Glas, Annuska M.; van de Vijver, Marc J.

    2009-01-01

    Purpose: The level of estrogen receptor (ER), progesterone receptor (PR), and HER2 aids in the determination of prognosis and treatment of breast cancer. Immunohistochemistry is currently the predominant method for assessment, but differences in methods and interpretation can substantially affect

  17. Progesterone receptor isoform A may regulate the effects of neoadjuvant aglepristone in canine mammary carcinoma

    DEFF Research Database (Denmark)

    Guil-Luna, Silvia; Stenvang, Jan; Brünner, Nils

    2014-01-01

    , A and B, transcribed from a single gene. Experimental studies in human breast cancer suggest that the differential expression of progesterone receptor isoforms has implications for hormone therapy responsiveness. This study examined the effects of the antiprogestin aglepristone on cell proliferation and m......RNA expression of progesterone receptor isoforms A and B in mammary carcinomas in dogs treated with 20 mg/Kg of aglepristone (n¿=¿22) or vehicle (n¿=¿5) twice before surgery.ResultsFormalin-fixed, paraffin-embedded tissue samples taken before and after treatment were used to analyse total progesterone receptor......-receptor positive and isoform-A positive tumours in aglepristone-treated dogs.ConclusionsThese findings suggest that the antiproliferative effects of aglepristone in canine mammary carcinomas are mediated by progesterone receptor isoform A....

  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. Progesterone receptor content in endometrial carcinoma correlates with serum levels of free estradiol

    DEFF Research Database (Denmark)

    Nyholm, H C; Nielsen, Anette Lynge; Lyndrup, J

    1993-01-01

    cytosol by dextran charcoal-coated assay and immunohistochemically on frozen sections. Serum sex hormones were measured by radioimmunoassays. MAIN FINDINGS. Tumor biochemical progesterone receptor content correlated positively (p

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

    Science.gov (United States)

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

    2018-01-12

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

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

    Science.gov (United States)

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

    2018-01-01

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

  2. Progesterone receptor antagonist CDB-4124 increases depression-like behavior in mice without affecting locomotor ability

    OpenAIRE

    Beckley, Ethan H.; Scibelli, Angela C.; Finn, Deborah A.

    2010-01-01

    Progesterone withdrawal has been proposed as an underlying factor in premenstrual syndrome and postpartum depression. Progesterone withdrawal induces forced swim test (FST) immobility in mice, a depression-like behavior, but the contribution of specific receptors to this effect is unclear. The role of progesterone’s GABAA receptor-modulating metabolite allopregnanolone in depression- and anxiety-related behaviors has been extensively documented, but little attention has been paid to the role ...

  3. [Progesterone receptor gene polymorphism and recurrent spontaneous abortion].

    Science.gov (United States)

    Traina, Evelyn; Daher, Silvia; Franchim, Camila Sommerauer; Fuziy, Juliana Aoki; Moron, Antônio Fernandes; Banzato, Priscilla Chamelete Andrade; Mattar, Rosiane

    2010-05-01

    To assess a possible association between polymorphism of the progesterone receptor gene (PROGINS) and recurrent spontaneous abortion (RSA). In this case-control study, 85 women with at least three previous spontaneous abortions without an identifiable cause (RSA Group) and 157 women with at least two previous term pregnancies without pathologies and no previous miscarriage (Control Group) were selected. An amount of 10 mL of peripheral blood was collected by venipuncture and genomic DNA was extracted by the DTAB/CTAB method, followed by the polymerase chain reaction (PCR) under specific conditions for this polymorphism and by amplification by 2% agarose gel electrophoresis. The bands were visualized with an ultraviolet light transilluminator and the gels were photographed. Differences in the PROGINS genotype and allele frequencies between groups were analyzed by the χ² test, with the level of significance set at p<0.05. The Odds Ratio (OR) was also used, with 95% confidence intervals 95%CI. PROGINS genotypic frequencies were 72.3% T1T1 and 27.7% T1T2 for the RSA group and 76.4% T1T1, 22.3% T1T2 and 1.3% T2T2 for the control group. There were no differences between groups when the genotype and allele frequencies were analyzed: respectively p=0.48 (OR: 0.8) and p=0.65 (OR: 0.9). Our results suggest that PROGINS polymorphism is not associated with RSA.

  4. Bone growth and turnover in progesterone receptor knockout mice.

    Energy Technology Data Exchange (ETDEWEB)

    Rickard, David J.; Iwaniec, Urszula T.; Evans, Glenda; Hefferan, Theresa E.; Hunter, Jaime C.; Waters, Katrina M.; Lydon, John P.; O' Malley, Bert W.; Khosla, Sundeep; Spelsberg, Thomas C.; Turner, Russell T.

    2008-05-01

    The role of progesterone receptor (PR) signaling in skeletal metabolism is controversial. To address whether signaling through the PR is necessary for normal bone growth and turnover, we performed histomorphometric and mCT analyses of bone from homozygous female PR knockout (PRKO) mice at 6, 12, and 26 weeks of age. These mice possess a null mutation of the PR locus, which blocks the gene expression of A and B isoforms of PR. Body weight gain, uterine weight gain and tibia longitudinal bone growth was normal in PRKO mice. In contrast, total and cortical bone mass were increased in long bones of post-pubertal (12 and 26-week-old) PRKO mice, whereas cancellous bone mass was normal in the tibia but increased in the humerus. The striking 57% decrease in cancellous bone from the proximal tibia metaphysis which occurred between 6 and 26 weeks in WT mice was abolished in PRKO mice. The improved bone balance in aging PRKO mice was associated with elevated bone formation and a tendency toward reduced osteoclast perimeter. Taken together, these findings suggest that PR signaling in mice attenuates the accumulation of cortical bone mass during adolescence and is required for early age-related loss of cancellous bone.

  5. Immunolocalization of progesterone receptors in binucleate trophoblast cells of the buffalo placenta (Bubalus bubalis

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Ambrósio

    2007-06-01

    Full Text Available The binucleate trophoblast cells (CTBs of the water buffalo placenta (Bubalus bubalis were studied with emphasis on the presence of progesterone receptor. Placentomal tissues from 27 buffalos (2-10 months of pregnancy were processed and embedded in paraplast (Paraplast Embedding Media – Paraplast Plus to locate the progesterone receptors using the immunohistochemistry technique. The immunohistochemical reaction for progesterone receptor through monoclonal antibody PgR Ab2 showed staining of CTBs, caruncular epithelial and estromal cells and blood vessel estromal pericitos present in the placentome throughout the entire gestational period analyzed. These results indicate the production of progesterone with autocrine and paracrine action in the placentome growth, differentiation and functional regulation.

  6. Expression of estrogen and progesterone receptors in vestibular schwannomas and their clinical significance

    Directory of Open Access Journals (Sweden)

    Pandey Rakesh

    2009-11-01

    Full Text Available Abstract Objective The objective was to determine the expression of estrogen and progesterone receptors in vestibular schwannomas as well as to determine predictive factors for estrogen and progesterone receptor positivity. Materials and methods The study included 100 cases of vestibular schwannomas operated from January 2006 to June 2009. The clinical details were noted from the medical case files. Formaldehyde-fixed parafiin-embedded archival vestibular schwannomas specimens were used for the immunohistochemical assessment of estrogen and progesterone receptors. Results Neither estrogen nor progesterone receptors could be detected in any of our cases by means of well known immunohistochemical method using well documented monoclonal antibodies. In the control specimens, a strongly positive reaction could be seen. Conclusion No estrogen and progesterone receptor could be found in any of our 100 cases of vestibular schwannomas. Hence our study does not support a causative role of estrogen and progesterone in the growth of vestibular schwannoma as well as hormonal manipulation in the treatment of this tumor.

  7. Extra-nuclear signaling of progesterone receptor to breast cancer cell movement and invasion through the actin cytoskeleton.

    Directory of Open Access Journals (Sweden)

    Xiao-Dong Fu

    2008-07-01

    Full Text Available Progesterone plays a role in breast cancer development and progression but the effects on breast cancer cell movement or invasion have not been fully explored. In this study, we investigate the actions of natural progesterone and of the synthetic progestin medroxyprogesterone acetate (MPA on actin cytoskeleton remodeling and on breast cancer cell movement and invasion. In particular, we characterize the nongenomic signaling cascades implicated in these actions. T47-D breast cancer cells display enhanced horizontal migration and invasion of three-dimensional matrices in the presence of both progestins. Exposure to the hormones triggers a rapid remodeling of the actin cytoskeleton and the formation of membrane ruffles required for cell movement, which are dependent on the rapid phosphorylation of the actin-regulatory protein moesin. The extra-cellular small GTPase RhoA/Rho-associated kinase (ROCK-2 cascade plays central role in progesterone- and MPA-induced moesin activation, cell migration and invasion. In the presence of progesterone, progesterone receptor A (PRA interacts with the G protein G alpha(13, while MPA drives PR to interact with tyrosine kinase c-Src and to activate phosphatidylinositol-3 kinase, leading to the activation of RhoA/ROCK-2. In conclusion, our findings manifest that progesterone and MPA promote breast cancer cell movement via rapid actin cytoskeleton remodeling, which are mediated by moesin activation. These events are triggered by RhoA/ROCK-2 cascade through partially differing pathways by the two compounds. These results provide original mechanistic explanations for the effects of progestins on breast cancer progression and highlight potential targets to treat endocrine-sensitive breast cancers.

  8. Detection of oestrogen and progesterone receptor expression in breast tumors by semiquantitative PCR.

    Science.gov (United States)

    Hackl, T; Zickl, M; Dobianer, K; Hruza, C; Czerwenka, K; Spona, J

    1998-01-01

    Estimation of oestrogen receptors (ER) and progesterone receptors (PgR) by dextran-coated charcoal (DCC) or immunohistochemical methods have become standard practices in the management of breast cancer. A "multiplex" polymerase chain reaction (PCR) system was developed for quantitative estimation of ER and PgR mRNA in breast tumour specimens. A statistically significant correlation could be found between the mRNA of the oestrogen and the progesterone receptor (p < or = 0.0001). Protein data defined in classes, compared with mRNA data showed a significant correlation for the oestrogen receptor (p < or = 0.0001) as well as for the progesterone receptor (p < or = 0.046). Messenger RNA could be determined by the present PCR system in tumours assayed as negative by DCC method. Therefore, this sensitive PCR procedure, which requires small amounts of material may be very useful as a diagnostic test to determine the choice of therapy.

  9. Regulation of uterine progesterone receptors by the nonsteroidal anti-androgen hydroxyflutamide

    International Nuclear Information System (INIS)

    Chandrasekhar, Y.; Armstrong, D.T.

    1991-01-01

    The authors have recently reported that the anti-androgen hydroxyflutamide causes delayed implantation and exhibits antideciduogenic activity in the rat. The present experiments were conducted to examine whether hydroxyflutamide binds to the uterine progesterone receptors and/or alters the progesterone binding sites in the uterus. Cytosol and nuclear fractions from decidualized rat uterus were incubated with [3H]-R5020 without or with increasing concentrations of radioinert R5020, RU486, dihydrotestosterone, or hydroxyflutamide. From the log-dose inhibition curves, the relative binding affinity of both hydroxyflutamide and dihydrotestosterone was less than 0.1% and 2%, compared with R5020 (100%) for displacing [3H]-R5020 bound to uterine cytosol and nuclear fractions, respectively. Injection of estradiol-17 beta (1 microgram/rat) to ovariectomized prepubertal rats induced a 1.85-fold increase in uterine weight by 24 h. Hydroxyflutamide at 2.5 or 5.0 mg did not significantly alter the estrogen-induced increase in uterine weight. Compared to vehicle alone, estrogen induced an approximately 5-fold increase in uterine cytosolic progesterone binding sites. Hydroxyflutamide at both 2.5- and 5.0-mg doses significantly attenuated the estrogen-induced elevation in uterine progesterone binding sites. These studies demonstrate that hydroxyflutamide does not bind with high affinity to progesterone receptors, but suppresses the estrogen-induced elevation in progesterone receptor levels in the uterus

  10. Selectivity in progesterone and androgen receptor binding of progestagens used in oral contraceptives

    Energy Technology Data Exchange (ETDEWEB)

    Kloosterboer, H.J.; Vonk-Noordegraaf, C.A.; Turpijn, E.W.

    1988-09-01

    The relative binding affinities (RBAs) of four progestational compounds (norethisterone, levonorgestrel, 3-keto-desogestrel and gestodene) for the human progesterone and androgen receptors were measured in MCF-7 cytosol and intact MCF-7 cells. For the binding to the progesterone receptor, both Org 2058 and Org 3236 (or 3-keto-desogestrel) were used as labelled ligands. The following ranking (low to high) for the RBA of the nuclear (intact cells) progesterone receptor irrespective of the ligand used is found: norethisterone much less than levonorgestrel less than 3-keto-destogestrel less than gestodene. The difference between the various progestagens is significant with the exception of that between 3-keto-desogestrel and gestodene, when Org 2058 is used as ligand. For the cytosolic progesterone receptor, the same order is found with the exception that similar RBAs are found for gestodene and 3-keto-desogestrel. The four progestagens clearly differ with respect to binding to the androgen receptor using dihydrotestosterone as labelled ligand in intact cells; the ranking (low to high) is: norethisterone less than 3 keto-desogestrel less than levonorgestrel and gestodene. The difference between 3-keto-desogestrel and levonorgestrel or gestodene is significant. The selectivity indices (ratio of the mean RBA for the progesterone receptor to that of androgen receptor) in intact cells are significantly higher for 3-keto-desogestrel and gestodene than for levonorgestrel and norethisterone. From these results we conclude that the introduction of the 18-methyl in norethisterone (levonorgestel) increases both the binding to the progesterone and androgen receptors.

  11. The Biology of Progesterone Receptor in the Normal Mammary gland and in Breast Cancer

    Science.gov (United States)

    Obr, Alison; Edwards, Dean P.

    2011-01-01

    This paper reviews work on progesterone and the progesterone receptor (PR) in the mouse mammary gland that has been used extensively as an experimental model. Studies have led to the concept that progesterone controls proliferation and morphogenesis of the luminal epithelium in a tightly orchestrated manner at distinct stages of development by paracrine signaling pathways, including receptor of activated nuclear factor κ ligand (RANKL) as a major paracrine factor. Progesterone also drives expansion of stem cells by paracrine signals to generate progenitors required for alveologenesis. During mid-to-late pregnancy, progesterone has another role to suppress secretory activation until parturition mediated in part by crosstalk between PR and prolactin/Stat5 signaling to inhibit induction of milk protein gene expression, and by inhibiting tight junction closure. In models of hormone-dependent mouse mammary tumors, the progesterone/PR signaling axis enhances pre-neoplastic progression by a switch from a paracrine to an autocrine mode of proliferation and dysregulation of the RANKL signaling pathway. Limited experiments with normal human breast show that progesterone/PR signaling also stimulates epithelial cell proliferation by a paracrine mechanism; however, the signaling pathways and whether RANKL is a major mediator remains unknown. Work with human breast cancer cell lines, patient tumor samples and clinical studies indicates that progesterone is a risk factor for breast cancer and that alteration in progesterone/PR signaling pathways contributes to early stage human breast cancer progression. However, loss of PR expression in primary tumors is associated with a less differentiated more invasive phenotype and worse prognosis, suggesting that PR may limit later stages of tumor progression. PMID:22193050

  12. Effects of ionizing irradiation on the estradiol and progesterone receptors in rat mammary tumors

    International Nuclear Information System (INIS)

    Janssens, J.P.; Wittevrongel, C.; Van Dam, J.; Goddeeris, P.; Lauwerijns, J.M.; De Loecker, W.

    1981-01-01

    The determination of estradiol and progesterone receptor concentrations in mammary tumors is useful in predicting the hormone responsiveness. As this assay is carried out on tumor tissue which may have been subjected to radiotherapy, the possibility of an ionizing irradiation affecting the steroid receptor levels in neoplastic tissue should be taken into account. The steroid receptor concentrations are examined in dimethylbenz(a)anthracene-induced tumors os Sprague-Dawley rats. The estradiol and the progesterone receptor titers become reduced significantly after treatment with 20 Gray while an application with 7 Gray does not affect the titer values. After treatment of the tumor with 20 Gray, the steroid receptor concentrations decrease progressively, reaching a maximal reduction 20 to 30 days after exposure. As radiation treatment affects the receptor concentrations, this should be kept in mind when interpreting the steroid receptor concentrations

  13. Expression of Progesterone and Androgen Receptors in the Breast of Premenopausal Women, Considering Menstrual Phase.

    Science.gov (United States)

    Fahlén, Mia; Zhang, Hua; Löfgren, Lars; Masironi, Britt; VON Schoultz, Eva; VON Schoultz, B O; Sahlin, Lena

    2018-03-01

    Progesterone and androgens are important for normal development and tumorigenesis of the breast. Breast tissue samples from 49 premenopausal women were obtained. The progesterone receptors (PRA, PRB, PGRMC1 and PGRMC2) and the androgen receptor (AR) were determined in malignant and benign breast tumors and control tissues. The PRB and AR mRNA levels were highest in tumors. PGRMC1 and PGRMC2 mRNA levels were higher in malignant tumors compared to their paired normal tissues. PRA protein showed most immunostaining in benign tumors. PRB immunostaining varied according to menstrual phase. AR immunostaining was highest in the glands of malignant tumors. Progesterone and androgen receptors are differently regulated in tumors compared to normal breast tissues. A malignant breast tumor could appear PR-negative if collected in the luteal phase, but positive in the follicular phase. This finding may have clinical implications. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  14. Effect of pharmacological inhibition of Progesterone receptors PGRMC1 and nPR on bovine oocyte meiosis.

    Directory of Open Access Journals (Sweden)

    Laura Terzaghi

    2017-05-01

    Full Text Available Folliculogenesis is the fundamental process leading to oocyte maturation and its developmental competence, which are determined by oocyte and follicular cells interplay (Luciano et al., 2004. Recent studies in cattle describe Progesterone (P4 as a key molecule acting during follicle development through different signaling pathways involving different receptors (Aparicio et al., 2011, Nilsson et al., 2009. The aim of this study is to evaluate the effect on oocyte meiotic maturation of inhibiting two P4 receptors: Progesterone Receptor Membrane Component 1 (PGRMC1 and the classic nuclear Progesterone Receptor (nPR respectively using the specific inhibitors AG205 and Aglepristone. Bovine cumulus cell-oocyte complexes (COCs and denuded oocytes (DOs were in vitro matured with different concentrations of AG205. Our results showed a decrease both in first polar body (PBI extrusion and in the percentage of oocytes reaching MII stage in treated oocytes compared to controls (one way ANOVA, P<0.05; these effects were more marked in DOs, confirming PGRMC1 specific role in the oocyte. In AG205 treated oocytes aberrant meiotic figures were observed, including double metaphase plates or DNA scattered in the ooplasm. In addition, aberrant meiotic plates showed irregular co-localization of PGRMC1 and AURKB; the proteins didn’t localize at the centromeric region of each chromosomes as previously described (Luciano et al., 2013. This results suggests a P4 role in meiotic division mediated by PGRMC1 receptor. By contrast, Aglepristone inhibition of nPR didn’t affect dramatically the percentage of oocytes reaching MII stage of maturation. However, MII plates morphology analysis showed a significantly greater tubulin spindle length. This feature could account for the previously described reduced in vitro embryo development consequent to nPR inhibition (Aparicio et al., 2011. Thus, P4 driven nuclear maturation could act on different oocyte development stages

  15. Estrogen and progesterone receptor assay using I-125 estradiol and H-3 promegestone as ligands: Results in female mammary carcinoma

    International Nuclear Information System (INIS)

    Glaubitt, D.; Hienz, H.A.; Bettges, G.; Carmanns, B.; Lichtenberg, T.; Akademisches Lehrkrankenhaus, Krefeld

    1984-01-01

    The determination of estrogen and progesterone receptors in the cytosol of carcinoma of the female breast has predictive value as to the success treatment of the patient. An improved estrogen and progesterone receptor assay using 1-125 labelled estradiol and a H-3 tagged synthetic gestagen (H-3 promegestone) as ligands proved to be highly praticable, especially time-saving. (orig.)

  16. Progesterone treatment shows greater protection in brain vs. retina in a rat model of middle cerebral artery occlusion: Progesterone receptor levels may play an important role.

    Science.gov (United States)

    Allen, Rachael S; Sayeed, Iqbal; Oumarbaeva, Yuliya; Morrison, Katherine C; Choi, Paul H; Pardue, Machelle T; Stein, Donald G

    2016-11-22

    To determine whether inflammation increases in retina as it does in brain following middle cerebral artery occlusion (MCAO), and whether the neurosteroid progesterone, shown to have protective effects in both retina and brain after MCAO, reduces inflammation in retina as well as brain. MCAO rats treated systemically with progesterone or vehicle were compared with shams. Protein levels of cytosolic NF-κB, nuclear NF-κB, phosphorylated NF-κB, IL-6, TNF-α, CD11b, progesterone receptor A and B, and pregnane X receptor were assessed in retinas and brains at 24 and 48 h using western blots. Following MCAO, significant increases were observed in the following inflammatory markers: pNF-κB and CD11b at 24 h in both brain and retina, nuclear NF-κB at 24 h in brain and 48 h in retina, and TNF-α at 24 h in brain.Progesterone treatment in MCAO animals significantly attenuated levels of the following markers in brain: pNF-κB, nuclear NF-κB, IL-6, TNF-α, and CD11b, with significantly increased levels of cytosolic NF-κB. Retinas from progesterone-treated animals showed significantly reduced levels of nuclear NF-κB and IL-6 and increased levels of cytosolic NF-κB, with a trend for reduction in other markers. Post-MCAO, progesterone receptors A and B were upregulated in brain and downregulated in retina. Inflammatory markers increased in both brain and retina after MCAO, with greater increases observed in brain. Progesterone treatment reduced inflammation, with more dramatic reductions observed in brain than retina. This differential effect may be due to differences in the response of progesterone receptors in brain and retina after injury.

  17. Revisiting progesterone receptor (PR) actions in breast cancer: Insights into PR repressive functions.

    Science.gov (United States)

    Proietti, Cecilia J; Cenciarini, Mauro E; Elizalde, Patricia V

    2018-05-01

    Progesterone receptor (PR) is a master regulator in female reproductive tissues that controls developmental processes and proliferation and differentiation during the reproductive cycle and pregnancy. PR also plays a role in progression of endocrine-dependent breast cancer. As a member of the nuclear receptor family of ligand-dependent transcription factors, the main action of PR is to regulate networks of target gene expression in response to binding its cognate steroid hormone, progesterone. Liganded-PR transcriptional activation has been thoroughly studied and associated mechanisms have been described while progesterone-mediated repression has remained less explored. The present work summarizes recent advances in the understanding of how PR-mediated repression is accomplished in breast cancer cells and highlights the significance of fully understanding the determinants of context-dependent PR action. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Progesterone prevents nerve injury-induced allodynia and spinal NMDA receptor upregulation in rats.

    Science.gov (United States)

    Coronel, María Florencia; Labombarda, Florencia; Roig, Paulina; Villar, Marcelo José; De Nicola, Alejandro Federico; González, Susana Laura

    2011-08-01

    Peripheral nerve injury-evoked neuropathic pain still remains a therapeutic challenge. Recent studies support the notion that progesterone, a neuroactive steroid, may offer a promising perspective in pain modulation. Evaluate the effect of progesterone administration on the development of neuropathic pain-associated allodynia and on the spinal expression of N-Methyl-D-Aspartate Receptor subunit 1 (NR1), its phosphorylated form (pNR1), and the gamma isoform of protein kinase C (PKCγ), all key players in the process of central sensitization, in animals subjected to a sciatic nerve constriction. Male Sprague-Dawley rats were subjected to a sciatic nerve single ligature constriction and treated with daily subcutaneous injections of progesterone (16 mg/kg) or vehicle. The development of hindpaw mechanical and thermal allodynia was assessed using the von Frey and Choi tests, respectively. Twenty two days after injury, the number of neuronal profiles exhibiting NR1, pNR1, or PKCγ immunoreactivity was determined in the dorsal horn of the lumbar spinal cord. Injured animals receiving progesterone did not develop mechanical allodynia and showed a significantly lower number of painful responses to cold stimulation. In correlation with the observed attenuation of pain behaviors, progesterone administration significantly reduced the number of NR1, pNR1, and PKCγ immunoreactive neuronal profiles. Our results show that progesterone prevents allodynia in a rat model of sciatic nerve constriction and reinforce its role as a potential treatment for neuropathic pain. Wiley Periodicals, Inc.

  19. Estrogen Receptor- and Progesterone Receptor-Positive Diffuse Sclerosing Variant of Papillary Thyroid Carcinoma: A Case Report

    Directory of Open Access Journals (Sweden)

    Yuichi Kinoshita

    2013-04-01

    Full Text Available The diffuse sclerosing variant of papillary thyroid carcinoma (DSV-PTC is a relatively rare tumor. We herein report the case of young woman with DSV-PTC who developed cervical lymph node recurrence 7 years after the initial surgery. A 15-year-old female patient with no medical or family history of thyroid tumors developed a thyroid neoplasm in the right lobe. Right thyroidectomy and regional lymphadenectomy were performed, and the tumor was diagnosed as DSV-PTC. She was followed up as an outpatient. Seven years after the surgery, cervical lymph node recurrence developed. On microscopic examination, the thyroid tumor showed a papillary growth pattern with numerous psammoma bodies and distinct fibrosis. Immunohistochemically, the tumor cells were estrogen receptor and progesterone receptor positive with reduced membranous expression of E-cadherin and were intermingled with S-100-positive dendritic/Langerhans cells. DSV-PTC is characterized by a strong tendency for invasion and metastasis. Thus, accurate diagnosis is clinically important, and a morphological and immunohistochemical understanding of DSV-PTC is necessary.

  20. Estrogen receptor and progesterone receptor synthesis and degradation in target cells

    Energy Technology Data Exchange (ETDEWEB)

    Nardulli, A.M.

    1987-01-01

    It was the intent of this study to determine the turnover of the estrogen receptor (ER) and progesterone receptors (PR) in rat uterine and human breast cancer cells, respectively, and to examine the effect of estrogen and progestin on PR levels. The rates of synthesis and degradation of ER were determined in rat uterine cells in vitro and in vivo. The affinity labeling antiestrogen, (/sup 3/H)tamoxifen aziridine, was used in pulse chase experiments to show that the 65,000 molecular weight ER has a half-life of 3-4h in primary cultures of rat uterine cells in vitro and in the intact rat uterus in vivo. Density shift analyses using dense (/sup 15/N, /sup 13/C, /sup 2/H) amino acid incorporation corroborate the rapid turnover of ER in rat uterine cell cultures. The regulation of PR by progestins in T47D human breast cancer cells was examined using density shift-dense amino acid incorporation. When T47D cells, which normally maintain high PR levels, are exposed to progestin (R5020), PR levels decline. Receptor half-life, which is 21h in control cells, is reduced to 6h when cells are exposed to 20 nM (/sup 3/H)R5020. In addition, PR synthesis rate declines exponentially following R5020 exposure. The reduction in receptor level is thus due to dramatic increases in PR degradation as well as marked decreases in PR synthesis.

  1. Loss of Progesterone Receptor-Mediated Actions Induce Preterm Cellular and Structural Remodeling of the Cervix and Premature Birth

    Science.gov (United States)

    Yellon, Steven M.; Dobyns, Abigail E.; Beck, Hailey L.; Kurtzman, James T.; Garfield, Robert E.; Kirby, Michael A.

    2013-01-01

    A decline in serum progesterone or antagonism of progesterone receptor function results in preterm labor and birth. Whether characteristics of premature remodeling of the cervix after antiprogestins or ovariectomy are similar to that at term was the focus of the present study. Groups of pregnant rats were treated with vehicle, a progesterone receptor antagonist (onapristone or mifepristone), or ovariectomized on day 17 postbreeding. As expected, controls given vehicle delivered at term while rats delivered preterm after progesterone receptor antagonist treatment or ovariectomy. Similar to the cervix before term, the preterm cervix of progesterone receptor antagonist-treated rats was characterized by reduced cell nuclei density, decreased collagen content and structure, as well as a greater presence of macrophages per unit area. Thus, loss of nuclear progesterone receptor-mediated actions promoted structural remodeling of the cervix, increased census of resident macrophages, and preterm birth much like that found in the cervix at term. In contrast to the progesterone receptor antagonist-induced advance in characteristics associated with remodeling, ovariectomy-induced loss of systemic progesterone did not affect hypertrophy, extracellular collagen, or macrophage numbers in the cervix. Thus, the structure and macrophage census in the cervix appear sufficient for premature ripening and birth to occur well before term. With progesterone receptors predominantly localized on cells other than macrophages, the findings suggest that interactions between cells may facilitate the loss of progesterone receptor-mediated actions as part of a final common mechanism that remodels the cervix in certain etiologies of preterm and with parturition at term. PMID:24339918

  2. Effects of dexamethasone on progesterone and estrogen profiles and uterine progesterone receptor localization during pregnancy in Sahel goat in Semi-Arid region.

    Science.gov (United States)

    Yahi, Dauda; Ojo, Nicholas Adetayo; Mshelia, Gideon Dauda

    2017-01-01

    Despite the widespread use of dexamethasone in veterinary and human medicine, it is reported to cause some severe pregnancy related side effects like abortion in some animals. The mechanism of the response is not clear but seems to be related to interspecies and/or breed difference in response which may involve alterations in the concentrations of some reproductive hormones. Twenty Sahel goats comprising 18 does and 2 bucks were used for this study. Pregnancies were achieved by natural mating after synchronization. Repeated dexamethasone injections were given at 0.25 mg/kg body weight. Blood samples were collected biweekly for hormonal assay. Uterine biopsies were harvested at days 28 and day 78 of gestation through caesarean section for immunohistochemical analysis using 3 pregnant does randomly selected from each group at each instant. Data were expressed as Means ± Standard Deviations and analyzed using statistical soft ware package, GraphPad Instant, version 3.0 (2003) and progesterone receptor (PR) were scored semi-quantitatively. Dexamethasone treatments had no significant ( p  > 0.05) effect on progesterone and estrogen concentrations in pregnant Sahel goats but up regulated PR from 2+ to 3+ in second trimester. As dexamethasone adverse effect on placenta is an established fact, the lack of effect on progesterone level in this study may be due to the fact that unlike other species whose progesterone production during pregnancy is placenta - dependent, in goats is corpus luteum - dependent. Consequently dexamethasone adverse effect on placenta reported in literatures did not influence progesterone levels during pregnancy in Sahel goat. The up regulation of progesterone receptor (PR) in Sahel goat gravid uterus is a beneficial effects and that dexamethasone can safely be used in corpus luteum - dependent progesterone secreting pregnant animal species like Sahel goat and camel. Therefore source of progesterone secretions during pregnancy should be

  3. Cytologic assessment of estrogen receptor, progesterone receptor, and HER2 status in metastatic breast carcinoma.

    Science.gov (United States)

    Pareja, Fresia; Murray, Melissa P; Jean, Ryan Des; Konno, Fumiko; Friedlander, Maria; Lin, Oscar; Edelweiss, Marcia

    2017-01-01

    Discordance in the receptor status between primary breast carcinomas (PBC) and corresponding metastasis is well documented. Interrogation of the receptor status of metastatic breast carcinoma (MBC) in cytology material is common practice; however, its utility has not been thoroughly validated. We studied patients with MBC, and evaluated the concordance rates of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) between PBC surgical specimens and corresponding MBC cell blocks (CBs). We correlated the findings with clinicopathologic variables and with the fixation methods used. We searched for patients with MBC diagnosed on cytology from 2007 to 2009 and selected those with ER, PR and HER2 tested in both the PBC surgical specimens and the MBC CBs. We included CBs fixed in formalin and methanol based solution (CytoLyt®). All slides were reevaluated by cytopathologists. Clinical information was retrieved from the medical records. We studied 65 patients with PBC and MBC paired specimens. The concordance rates between PBC and MBC were 78.5%, 58.5% and 96.9%, for ER, PR and HER2, respectively. When discordant, PR status switched from positive (PBC) to negative (MBC) in most cases (23/27). The PR concordance rate was 45.2% for CBs fixed in formalin and 70.6% for those fixed with CytoLyt® (p=0.047). The ER, PR and HER2 concordance rates between the PBC and MBC CBs are similar to those reported in paired surgical specimens. PR status was the most prevalent discordance and was not accompanied by a switch in ER.

  4. A Role of Endogenous Progesterone in Stroke Cerebroprotection Revealed by the Neural-Specific Deletion of Its Intracellular Receptors.

    Science.gov (United States)

    Zhu, Xiaoyan; Fréchou, Magalie; Liere, Philippe; Zhang, Shaodong; Pianos, Antoine; Fernandez, Neïké; Denier, Christian; Mattern, Claudia; Schumacher, Michael; Guennoun, Rachida

    2017-11-08

    Treatment with progesterone protects the male and female brain against damage after middle cerebral artery occlusion (MCAO). However, in both sexes, the brain contains significant amounts of endogenous progesterone. It is not known whether endogenously produced progesterone enhances the resistance of the brain to ischemic insult. Here, we used steroid profiling by gas chromatography-tandem mass spectrometry (GC-MS/MS) for exploring adaptive and sex-specific changes in brain levels of progesterone and its metabolites after MCAO. We show that, in the male mouse brain, progesterone is mainly metabolized via 5α-reduction leading to 5α-dihydroprogesterone (5α-DHP), also a progesterone receptor (PR) agonist ligand in neural cells, then to 3α,5α-tetrahydroprogesterone (3α,5α-THP). In the female mouse brain, levels of 5α-DHP and 3α,5α-THP are lower and levels of 20α-DHP are higher than in males. After MCAO, levels of progesterone and 5α-DHP are upregulated rapidly to pregnancy-like levels in the male but not in the female brain. To assess whether endogenous progesterone and 5α-DHP contribute to the resistance of neural cells to ischemic damage, we inactivated PR selectively in the CNS. Deletion of PR in the brain reduced its resistance to MCAO, resulting in increased infarct volumes and neurological deficits in both sexes. Importantly, endogenous PR ligands continue to protect the brain of aging mice. These results uncover the unexpected importance of endogenous progesterone and its metabolites in cerebroprotection. They also reveal that the female reproductive hormone progesterone is an endogenous cerebroprotective neurosteroid in both sexes. SIGNIFICANCE STATEMENT The brain responds to injury with protective signaling and has a remarkable capacity to protect itself. We show here that, in response to ischemic stroke, levels of progesterone and its neuroactive metabolite 5α-dihydroprogesterone are upregulated rapidly in the male mouse brain but not in the

  5. Effect of Progesterone on Latent Phase Prolongation in Patients With Preterm Premature Rupture of Membranes

    Directory of Open Access Journals (Sweden)

    Fatemeh Abdali

    2018-01-01

    Full Text Available Preterm premature rupture of membranes (PPROM is a condition leading to an increased risk of maternal and neonatal morbidity and mortality in pregnant women. To prevent this complication, some studies have proposed using prophylactic progesterone. However, due to lack of sufficient relevant data, there is still need for further studies in this regard. This study was performed to determine the effect of rectal progesterone on the latent phase and maternal and neonatal outcome variables in females with PPROM. During the present randomized clinical trial study (IRCT201512077676N4, a total of 120 patients with PPROM at pregnancy ages between 26 and 32 weeks were randomly assigned to 2 equal intervention and control groups. In the intervention group, progesterone suppositories (400 mg per night were administered until delivery or completion of the 34th gestational week and was compared with placebo effect in control group. The latent phase and maternal and neonatal outcome variables were compared between the two groups. The mean age of patients was 29.56±5.66 (19-42 and 29.88±5.57 (17-40 years in the intervention and control group, respectively. The two groups were almost identical in the confounding factors. The median latent phase was 8.5 days in the intervention group vs. 5 days in the control group in the 28th-30th weeks of gestation, which was significantly higher in the intervention group (P=0.001. Among maternal and neonatal outcome variables, only the mean birth-weight was significantly higher in the intervention group than that in the controls (1609.92±417.28 gr vs. 1452.03±342.35 gr, P=0.03. Administration of progesterone suppository in patients with PPROM at gestational ages of 28 to 30 weeks is effective in elongating the latent phase and increasing birth-weight with no significant complications.

  6. Conventional progesterone receptors (PR) B and PRA are expressed in human spermatozoa and may be involved in the pathophysiology of varicocoele: a role for progesterone in metabolism.

    Science.gov (United States)

    De Amicis, F; Guido, C; Perrotta, I; Avena, P; Panza, S; Andò, S; Aquila, S

    2011-10-01

    The physiological roles of intracellular progesterone (PRG) receptors (PRs) have been studied intensively in female mammals, while their functions in male are scarce. Conventional PRs were evidenced in our study by Western blotting, concomitantly in healthy spermatozoa and in oligoasthenoteratozoospermic samples without and with varicocoele. Transmission electron microscopy revealed the presence of the PRs on the membrane as well as in the nucleus, mitochondria and flagellum. A reduced expression of the PRs was observed only in varicocoele spermatozoa. Responses to PRG treatment on cholesterol efflux, tyrosine phosphorylation, src and Akt activities, acrosin activity and acrosome reaction in varicocoele spermatozoa were reduced or absent. To further investigate PRG significance in human male gamete, we focused its action on lipid and glucose metabolism. The evaluation of the triglycerides content, lipase and acyl-CoA dehydrogenase activities suggests that PRG through the PRs exerts a lipolytic effect on human spermatozoa. An increase in glucose-6-phosphate dehydrogenase activity was also obtained, evidencing a role for PRG on glucose metabolism. In 'varicocoele' spermatozoa, the PRG did not induce energy consumption. The action of PRs on sperm metabolism is a novel finding that renews the importance of PRG in male fertility. Our results showed that varicocoele may lead to male factor infertility by a mechanism involving a decreased PR expression in human spermatozoa that evidences a detrimental effect on spermatozoa at the molecular level, going beyond the abnormal sperm morphology described to date. © 2010 The Authors. International Journal of Andrology © 2011 European Academy of Andrology.

  7. Development of poly(lactic acid) nanostructured membranes for the controlled delivery of progesterone to livestock animals

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Juliano Elvis [Laboratorio Nacional de Nanotecnologia para o Agronegocio (LNNA), Embrapa Instrumentacao (CNPDIA), Rua XV de Novembro, 1452, Centro, 13.560, 970 Sao Carlos, SP (Brazil); Medeiros, Eliton Souto [Universidade Federal da Paraiba (UFPB), Departamento de Engenharia de Materiais (DEMAT), Cidade Universitaria, 58.051-900, Joao Pessoa, PB (Brazil); Cardozo, Lucio; Voll, Fernando [Departamento de Engenharia Quimica, Universidade Estadual de Maringa (UEM), 87.020, 900 Maringa, PR (Brazil); Madureira, Ed Hoffmann [Departamento de Reproducao Animal, Faculdade de Medicina Veterinaria e Zootecnia (FMVZ), Universidade de Sao Paulo (USP), Pirassununga-SP (Brazil); Mattoso, Luiz Henrique Capparelli, E-mail: mattoso@cnpdia.embrapa.br [Laboratorio Nacional de Nanotecnologia para o Agronegocio (LNNA), Embrapa Instrumentacao (CNPDIA), Rua XV de Novembro, 1452, Centro, 13.560, 970 Sao Carlos, SP (Brazil); Assis, Odilio Benedito Garrido [Laboratorio Nacional de Nanotecnologia para o Agronegocio (LNNA), Embrapa Instrumentacao (CNPDIA), Rua XV de Novembro, 1452, Centro, 13.560, 970 Sao Carlos, SP (Brazil)

    2013-03-01

    Solution blow spinning (SBS) is a novel technology feasible to produce nanostructured polymeric membranes loaded with active agents. In the present study, nanofibrous mats of poly(lactic acid) (PLA) loaded with progesterone (P4) were produced by SBS at different P4 concentrations. The spun membranes were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). The in vitro releasing of P4 was evaluated using high-performance liquid chromatography (HPLC). Interactions between progesterone and PLA were confirmed by rheological measurements of the PLA/P4 solutions and in the spun mats by microscopy (SEM), thermal (DSC) and spectral (FTIR) analyses. SEM micrographs provided evidences of a smooth and homogeneous structure for nanostructured membranes without progesterone crystals on fiber surface. FTIR spectroscopy indicated miscibility and interaction between the ester of PLA and the ketone groups of the P4 in the nanofibers. X-ray analysis indicated that the size of PLA crystallites increased with progesterone content. Finally, by in vitro release experiments it was possible to observe that the progesterone releasing follows nearly first-order kinetics, probably due to the diffusion of hormone into PLA nanofibers. - Highlights: Black-Right-Pointing-Pointer Nanofibers of PLA loading with progesterone were prepared via solution blow spinning. Black-Right-Pointing-Pointer Their morphology, FTIR, and XRD and DSC characterization were analyzed. Black-Right-Pointing-Pointer Fibers of PLA/progesterone with diameters from 280 to 440 nm were obtained. Black-Right-Pointing-Pointer The effect of progesterone content in fiber properties was studied.

  8. Development of poly(lactic acid) nanostructured membranes for the controlled delivery of progesterone to livestock animals

    International Nuclear Information System (INIS)

    Oliveira, Juliano Elvis; Medeiros, Eliton Souto; Cardozo, Lucio; Voll, Fernando; Madureira, Ed Hoffmann; Mattoso, Luiz Henrique Capparelli; Assis, Odilio Benedito Garrido

    2013-01-01

    Solution blow spinning (SBS) is a novel technology feasible to produce nanostructured polymeric membranes loaded with active agents. In the present study, nanofibrous mats of poly(lactic acid) (PLA) loaded with progesterone (P4) were produced by SBS at different P4 concentrations. The spun membranes were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). The in vitro releasing of P4 was evaluated using high-performance liquid chromatography (HPLC). Interactions between progesterone and PLA were confirmed by rheological measurements of the PLA/P4 solutions and in the spun mats by microscopy (SEM), thermal (DSC) and spectral (FTIR) analyses. SEM micrographs provided evidences of a smooth and homogeneous structure for nanostructured membranes without progesterone crystals on fiber surface. FTIR spectroscopy indicated miscibility and interaction between the ester of PLA and the ketone groups of the P4 in the nanofibers. X-ray analysis indicated that the size of PLA crystallites increased with progesterone content. Finally, by in vitro release experiments it was possible to observe that the progesterone releasing follows nearly first-order kinetics, probably due to the diffusion of hormone into PLA nanofibers. - Highlights: ► Nanofibers of PLA loading with progesterone were prepared via solution blow spinning. ► Their morphology, FTIR, and XRD and DSC characterization were analyzed. ► Fibers of PLA/progesterone with diameters from 280 to 440 nm were obtained. ► The effect of progesterone content in fiber properties was studied.

  9. Growth of a progesterone receptor-positive meningioma in a female patient with congenital adrenal hyperplasia.

    Science.gov (United States)

    O'Shea, T; Crowley, R K; Farrell, M; MacNally, S; Govender, P; Feeney, J; Gibney, J; Sherlock, M

    2016-01-01

    Meningioma growth has been previously described in patients receiving oestrogen/progestogen therapy. We describe the clinical, radiological, biochemical and pathologic findings in a 45-year-old woman with congenital adrenal hyperplasia secondary to a defect in the 21-hydroxylase enzyme who had chronic poor adherence to glucocorticoid therapy with consequent virilisation. The patient presented with a frontal headache and marked right-sided proptosis. Laboratory findings demonstrated androgen excess with a testosterone of 18.1 nmol/L (0-1.5 nmol) and 17-Hydroxyprogesterone >180 nmol/L (transsexual patients undergoing therapy with high-dose oestrogen and progestogens. Progesterone receptor positivity has been described previously in meningiomas. 17-Hydroxyprogesterone is elevated in CAH and has affinity and biological activity at the progesterone receptor. Therefore, we hypothesise that patients who have long-standing increased adrenal androgen precursor concentrations may be at risk of meningioma growth. Patients with long-standing CAH (particularly if not optimally controlled) may present with other complications, which may be related to long-standing elevated androgen or decreased glucocorticoid levels.Chronic poor control of CAH is associated with adrenal myelolipoma and adrenal rest tissue tumours.Meningiomas are sensitive to endocrine stimuli including progesterone, oestrogen and androgens as they express the relevant receptors.

  10. Mineralocorticoid receptor haplotype, estradiol, progesterone and emotional information processing.

    Science.gov (United States)

    Hamstra, Danielle A; de Kloet, E Ronald; Quataert, Ina; Jansen, Myrthe; Van der Does, Willem

    2017-02-01

    Carriers of MR-haplotype 1 and 3 (GA/CG; rs5522 and rs2070951) are more sensitive to the influence of oral contraceptives (OC) and menstrual cycle phase on emotional information processing than MR-haplotype 2 (CA) carriers. We investigated whether this effect is associated with estradiol (E2) and/or progesterone (P4) levels. Healthy MR-genotyped premenopausal women were tested twice in a counterbalanced design. Naturally cycling (NC) women were tested in the early-follicular and mid-luteal phase and OC-users during OC-intake and in the pill-free week. At both sessions E2 and P4 were assessed in saliva. Tests included implicit and explicit positive and negative affect, attentional blink accuracy, emotional memory, emotion recognition, and risky decision-making (gambling). MR-haplotype 2 homozygotes had higher implicit happiness scores than MR-haplotype 2 heterozygotes (p=0.031) and MR-haplotype 1/3 carriers (pinformation processing and P4 or E2 differed between sessions, as well as the moderating effects of the MR genotype. In the first session the MR-genotype moderated the influence of P4 on implicit anxiety (sr=-0.30; p=0.005): higher P4 was associated with reduction in implicit anxiety, but only in MR-haplotype 2 homozygotes (sr=-0.61; p=0.012). In the second session the MR-genotype moderated the influence of E2 on the recognition of facial expressions of happiness (sr=-0.21; p=0.035): only in MR-haplotype 1/3 higher E2 was correlated with happiness recognition (sr=0.29; p=0.005). In the second session higher E2 and P4 were negatively correlated with accuracy in lag2 trials of the attentional blink task (pinformation processing. This moderating effect may depend on the novelty of the situation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Biochemical and immunohistochemical estrogen and progesterone receptors in adenomatous hyperplasia and endometrial carcinoma: correlations with stage and other clinicopathologic features

    DEFF Research Database (Denmark)

    Nyholm, H C; Nielsen, A L; Lyndrup, J

    1992-01-01

    OBJECTIVE: This study investigates clinicopathologic associations of estrogen and progesterone receptor content in endometrial carcinoma. STUDY DESIGN: One hundred fifty-two patients with endometrial cancer and 12 with adenomatous hyperplasia were included. Dextran-coated charcoal receptor assay...... receptor dextran-coated charcoal values and immunohistochemical histologic scores correlated inversely (p charcoal values was independent...

  12. Characterization of estrogen receptor-negative/progesterone receptor-positive breast cancer.

    Science.gov (United States)

    Shen, Tiansheng; Brandwein-Gensler, Margaret; Hameed, Omar; Siegal, Gene P; Wei, Shi

    2015-11-01

    Despite the controversies, estrogen receptor-negative/progesterone receptor-positive (ER-/PR+) breast cancers have a reported incidence of 1% to 4%. These tumors are less well defined, and it is unclear whether ER-/PR+ represents a distinct subtype. Thus, we analyzed 5374 consecutive breast cancers to characterize the clinicopathological features of this underrecognized subset of tumors. The ER-/PR+ tumors, constituting 2.3% of the total, were mostly high grade and significantly seen in younger patients and African American women when compared with the ER+/PR+ and ER+/PR- groups, but similar to that of ER-/PR- phenotype (P < .0001). A significantly prolonged relapse-free survival (RFS) was associated with the ER+/PR+ subtype when compared with the ER+/PR- (P = .0002) or ER-/PR+ (P = .0004) tumors, whereas all 3 groups showed a superior outcome to that of the ER-/PR- phenotype. In the subset of patients receiving endocrine therapy, those with ER+/PR+ tumors had a significantly prolonged RFS (P = .001) and disease-specific survival (P = .005) when compared with the group with an ER+/PR- phenotype, but did not significantly differ from those with ER-/PR+ tumors. No significant survival advantage was found between the ER+/PR- and ER-/PR+ tumors in any group of patients analyzed. Furthermore, a higher PR expression was associated with a favorable RFS and disease-specific survival in the patients with ER-/PR+ tumors. Therefore, the ER-/PR+ tumors demonstrate a similar, if not higher than, response rate to endocrine therapy when compared with the ER+/PR- tumors and thus are important to identify. Routine PR testing remains necessary in assisting clinical decision making in the pursuit of precision medicine. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. ANTAGONISM OF PROGESTERONE RECEPTOR SUPPRESSES CAROTID BODY RESPONSES TO HYPOXIA AND NICOTINE IN RAT PUPS

    OpenAIRE

    JOSEPH, V.; NIANE, L. M.; BAIRAM, A.

    2012-01-01

    We tested the hypothesis that antagonism of progesterone receptor (PR) in newborn rats alters carotid body and respiratory responses to hypoxia and nicotinic receptor agonists. Rats were treated with the PR antagonist mifepristone (daily oral gavage 40 μg/g/d) or vehicle between post-natal days 3 and 15. In 11–14-day-old rats, we used in vitro carotid body/carotid sinus nerve preparation and whole body plethysmography to assess the carotid body and ventilatory responses to hypoxia (65 mmHg in...

  14. Immunologic analysis of human breast cancer progesterone receptors. 1. Immunonaffinity purification of transformed receptors and production of monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Estes, P.A.; Suba, E.J.; Lawler-Heavner, J.; Elashry-Stowers, D.; Wei, L.L.; Toft, D.O.; Sullivan, W.P.; Horwitz, K.B.; Edwards, D.P.

    1987-09-22

    A monoclonal antibody (MAb), designated PR-6, produced against chick oviduct progesterone receptors cross-reacts with the M/sub r/ 120,000 human B receptors. An immunomatrix prepared with PR-6 was used to purify progesterone receptors (PR) from T47D human breast cancer cells. Single-step immunoaffinity chromatography results in enrichment of B receptors (identified by immunoblot with PR-6 and by photoaffinity labeling with (/sup 3/H)promegestone) to a specific activity of 1915 pmol/mg of protein (or 23% purity) and with 27% yield. Purity and yields as judged by gel electrophoresis and densitometric scanning of the B protein were approximately 1.7-fold higher due to partial loss in hormone binding activity at the elution step. B receptors purified under these conditions are transformed and biologically active. They were maintained as undergraded 120-kDa doublets and retained both hormone and DNA binding activities. These purified B receptors were used as immunogen for production of four monoclonal antibodies against human PR. Three of the MAbs, designated as B-30 (IgG/sub 1/), B-64 (IgG/sub 1/), and B-11 (IgM), are specific for B receptors. The fourth MAb, A/B-52 (IgG/sub 1/), reacts with both A and B receptors. The IgG MAbs are monospecific for human PR since they recognize and absorb native receptor-hormone complexes, displace the sedimentation of 4S receptors on salt containing sucrose gradients, and, by immunoblot assay of crude T47D cytosol, react only with receptor polypeptides. Although mice were injected with B receptors only, production of A/B-52 which recognized both A and B receptors provides evidence that these two proteins share regions of structural homology.

  15. Dienogest increases the progesterone receptor isoform B/A ratio in patients with ovarian endometriosis

    Directory of Open Access Journals (Sweden)

    Hayashi Atsushi

    2012-11-01

    Full Text Available Abstract Background The resistance of endometriotic tissue to progesterone can be explained by alterations in the distribution of progesterone receptor (PR and estrogen receptor (ER isoforms. The aims of this study were to examine the expressions of PR-A, PR-B, ERα and ERβ in endometrioma and assess whether these expressions are affected by dienogest or leuprolide acetate (LA treatment. Methods We enrolled 60 females, including 43 patients with endometriosis (14 who received no medical treatment, 13 who received dienogest and 16 who received LA before undergoing laparoscopic surgery and 17 patients with leiomyoma. The expression levels of PR and ER isoforms in eutopic and ectopic endometrium were assayed with quantitative real-time PCR, and confirmed with immunohistochemistry. Results A decreased PR-B/PR-A ratio and an increased ERβ/ERα ratio were demonstrated in ectopic endometrium derived from females with endometriosis compared with the ratios observed in eutopic endometrium obtained from females without endometriosis. Although LA treatment did not affect the PR-B/PR-A and ERβ/ERα ratios, dienogest treatment increased the PR-B/PR-A ratio and decreased the ERβ/ERα ratio in patients with endometriomas. Conclusions Dienogest may improve progesterone resistance in endometriotic tissue by increasing the relative expressions of PR-B and PR-A, and decreasing the relative expressions of ERβ and ERα.

  16. Dienogest increases the progesterone receptor isoform B/A ratio in patients with ovarian endometriosis

    Science.gov (United States)

    2012-01-01

    Background The resistance of endometriotic tissue to progesterone can be explained by alterations in the distribution of progesterone receptor (PR) and estrogen receptor (ER) isoforms. The aims of this study were to examine the expressions of PR-A, PR-B, ERα and ERβ in endometrioma and assess whether these expressions are affected by dienogest or leuprolide acetate (LA) treatment. Methods We enrolled 60 females, including 43 patients with endometriosis (14 who received no medical treatment, 13 who received dienogest and 16 who received LA before undergoing laparoscopic surgery) and 17 patients with leiomyoma. The expression levels of PR and ER isoforms in eutopic and ectopic endometrium were assayed with quantitative real-time PCR, and confirmed with immunohistochemistry. Results A decreased PR-B/PR-A ratio and an increased ERβ/ERα ratio were demonstrated in ectopic endometrium derived from females with endometriosis compared with the ratios observed in eutopic endometrium obtained from females without endometriosis. Although LA treatment did not affect the PR-B/PR-A and ERβ/ERα ratios, dienogest treatment increased the PR-B/PR-A ratio and decreased the ERβ/ERα ratio in patients with endometriomas. Conclusions Dienogest may improve progesterone resistance in endometriotic tissue by increasing the relative expressions of PR-B and PR-A, and decreasing the relative expressions of ERβ and ERα. PMID:23113924

  17. Estrogen Receptor and Progesterone Receptor Expression in Normal Terminal Duct Lobular Units Surrounding Invasive Breast Cancer

    Science.gov (United States)

    Yang, Xiaohong R.; Figueroa, Jonine D.; Hewitt, Stephen M.; Falk, Roni T.; Pfeiffer, Ruth M.; Lissowska, Jolanta; Peplonska, Beata; Brinton, Louise A.; Garcia-Closas, Montserrat; Sherman, Mark E.

    2014-01-01

    Introduction Molecular and morphological alterations related to carcinogenesis have been found in terminal duct lobular units (TDLUs), the microscopic structures from which most breast cancer precursors and cancers develop, and therefore, analysis of these structures may reveal early changes in breast carcinogenesis and etiologic heterogeneity. Accordingly, we evaluated relationships of breast cancer risk factors and tumor pathology to estrogen receptor (ER) and progesterone receptor (PR) expression in TDLUs surrounding breast cancers. Methods We analyzed 270 breast cancer cases included in a population-based breast cancer case-control study conducted in Poland. TDLUs were mapped in relation to breast cancer: within the same block as the tumor (TDLU-T), proximal to tumor (TDLU-PT), or distant from (TDLU-DT). ER/PR was quantitated using image analysis of immunohistochemically stained TDLUs prepared as tissue microarrays. Results In surgical specimens containing ER-positive breast cancers, ER and PR levels were significantly higher in breast cancer cells than in normal TDLUs, and higher in TDLU-T than in TDLU-DT or TDLU-PT, which showed similar results. Analyses combining DT-/PT TDLUs within subjects demonstrated that ER levels were significantly lower in premenopausal women vs. postmenopausal women (odds ratio [OR]=0.38, 95% confidence interval [CI]=0.19, 0.76, P=0.0064) and among recent or current menopausal hormone therapy users compared with never users (OR=0.14, 95% CI=0.046–0.43, Ptrend=0.0006). Compared with premenopausal women, TDLUs of postmenopausal women showed lower levels of PR (OR=0.90, 95% CI=0.83–0.97, Ptrend=0.007). ER and PR expression in TDLUs was associated with epidermal growth factor receptor (EGFR) expression in invasive tumors (P=0.019 for ER and P=0.03 for PR), but not with other tumor features. Conclusions Our data suggest that TDLUs near breast cancers reflect field effects, whereas those at a distance demonstrate influences of breast

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

    International Nuclear Information System (INIS)

    Lenhard, Miriam; Tereza, Lennerová; Heublein, Sabine; Ditsch, Nina; Himsl, Isabelle; Mayr, Doris; Friese, Klaus; Jeschke, Udo

    2012-01-01

    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. 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. 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<0.001) OC. In contrast, ER-β negative OC had a favorable outcome (p=0.049). Besides tumor grade and stage, Cox-regression analysis showed PR-B to be an independent prognostic marker for patient survival (p=0.009, 95% CI 0.251-0.823, HR 0.455). 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

  19. Progesterone receptors (PR) mediate STAT actions: PR and prolactin receptor signaling crosstalk in breast cancer models.

    Science.gov (United States)

    Leehy, Katherine A; Truong, Thu H; Mauro, Laura J; Lange, Carol A

    2018-02-01

    Estrogen is the major mitogenic stimulus of mammary gland development during puberty wherein ER signaling acts to induce abundant PR expression. PR signaling, in contrast, is the primary driver of mammary epithelial cell proliferation in adulthood. The high circulating levels of progesterone during pregnancy signal through PR, inducing expression of the prolactin receptor (PRLR). Cooperation between PR and prolactin (PRL) signaling, via regulation of downstream components in the PRL signaling pathway including JAKs and STATs, facilitates the alveolar morphogenesis observed during pregnancy. Indeed, these pathways are fully integrated via activation of shared signaling pathways (i.e. JAKs, MAPKs) as well as by the convergence of PRs and STATs at target genes relevant to both mammary gland biology and breast cancer progression (i.e. proliferation, stem cell outgrowth, tissue cell type heterogeneity). Thus, rather than a single mediator such as ER, transcription factor cascades (ER>PR>STATs) are responsible for rapid proliferative and developmental programming in the normal mammary gland. It is not surprising that these same mediators typify uncontrolled proliferation in a majority of breast cancers, where ER and PR are most often co-expressed and may cooperate to drive malignant tumor progression. This review will primarily focus on the integration of PR and PRL signaling in breast cancer models and the importance of this cross-talk in cancer progression in the context of mammographic density. Components of these PR/PRL signaling pathways could offer alternative drug targets and logical complements to anti-ER or anti-estrogen-based endocrine therapies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Estrogen and progesterone receptors have distinct roles in the establishment of the hyperplastic phenotype in PR-A transgenic mice

    Energy Technology Data Exchange (ETDEWEB)

    Simian, Marina; Bissell, Mina J.; Barcellos-Hoff, Mary Helen; Shyamala, Gopalan

    2009-05-11

    Expression of the A and B forms of progesterone receptor (PR) in an appropriate ratio is critical for mammary development. Mammary glands of PR-A transgenic mice, carrying an additional A form of PR as a transgene, exhibit morphological features associated with the development of mammary tumors. Our objective was to determine the roles of estrogen (E) and progesterone (P) in the genesis of mammary hyperplasias/preneoplasias in PR-A transgenics. We subjected PR-A mice to hormonal treatments and analyzed mammary glands for the presence of hyperplasias and used BrdU incorporation to measure proliferation. Quantitative image analysis was carried out to compare levels of latency-associated peptide and transforming growth factor beta 1 (TGF{beta}1) between PR-A and PR-B transgenics. Basement membrane disruption was examined by immunofluorescence and proteolytic activity by zymography. The hyperplastic phenotype of PR-A transgenics is inhibited by ovariectomy, and is reversed by treatment with E + P. Studies using the antiestrogen ICI 182,780 or antiprogestins RU486 or ZK 98,299 show that the increase in proliferation requires signaling through E/estrogen receptor alpha but is not sufficient to give rise to hyperplasias, whereas signaling through P/PR has little impact on proliferation but is essential for the manifestation of hyperplasias. Increased proliferation is correlated with decreased TGF{beta}1 activation in the PR-A transgenics. Analysis of basement membrane integrity showed loss of laminin-5, collagen III and collagen IV in mammary glands of PR-A mice, which is restored by ovariectomy. Examination of matrix metalloproteases (MMPs) showed that total levels of MMP-2 correlate with the steady-state levels of PR, and that areas of laminin-5 loss coincide with those of activation of MMP-2 in PR-A transgenics. Activation of MMP-2 is dependent on treatment with E and P in ovariectomized wild-type mice, but is achieved only by treatment with P in PR-A mice. These data

  1. Immunologic analysis of human breast cancer progesterone receptors. 2. Structure, phosphorylation, and processing

    Energy Technology Data Exchange (ETDEWEB)

    Wei, L.L.; Sheridan, P.L.; Krett, N.L.; Francis, M.D.; Toft, D.O.; Edwards, D.P.; Horwitz, K.B.

    1987-09-22

    The authors have used a monoclonal antibody (MAb) directed against chick oviduct progesterone receptors (PR), that cross-reacts with human PR, to analyze PR structure and phosphorylation. This MAb, designated PR-6, interacts only with B receptors (M/sub r/ 120,000) of T47D human breast cancer cells; it has no affinity for A receptors (M/sub r/ 94,000) or for proteolytic fragments from either protein. The antibody immunoprecipitates native B receptors and was used to study the structure of native untransformed 8S and transformed 4S receptors, using sucrose density gradient analysis, photoaffinity labeling, and gel electrophoresis. The independence of A- and B-receptor complexes was confirmed by the fining that purified, transformed B receptors bind well to DNA-cellulose. Additional studies focused on the covalent modifications of receptors. The previously described shifts in apparent molecular weight of nuclear PR following R5020 treatment using in situ photoaffinity labeling. To show whether these shifts can be explained by receptor phosphorylation, untreated cells and hormone-treated cells were metabolically labeled with (/sup 32/P)orthophosphate, and the B receptors were isolated by immunoprecipitation with PR-6 and analyzed by sodium dodecyl sulfate (SDS) gel electrophoresis. In both treatment states, B receptors were labeled in vivo with /sup 32/P, thus demonstrating directly that human PR are phosphoproteins. Since B receptors were labeled in the absence of hormone and also after their in vivo transformation by hormone, they appear to be substrates for two phosphorylation reactions, one in the untransformed state and another after they are tightly bound to chromatin. The second phosphorylation may account for the mobility shift of the receptors on SDS gels. On the basis of these data a model of human PR structure and subcellular receptor dynamics is presented.

  2. Inhibition of progesterone receptor activity in recombinant yeast by soot from fossil fuel combustion emissions and air particulate materials

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jingxian; Xie, Ping [Donghu Experimental Station of the Lake Ecosystems, The State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072 (China); Kettrup, Antonius; Schramm, Karl-Werner [GSF-National Research Centre of Environment and Health, Institute of Ecological Chemistry, Ingolstaedter Landstr. 1, D-85764 Neuherberg (Germany)

    2005-10-15

    Numerous environmental pollutants have been detected for estrogenic activity by interacting with the estrogen receptor, but little information is available about their interactions with the progesterone receptor. In this study, emission samples generated by fossil fuel combustion (FFC) and air particulate material (APM) collected from an urban location near a traffic line in a big city of China were evaluated to interact with the human progesterone receptor (hPR) signaling pathway by examining their ability to interact with the activity of hPR expressed in yeast. The results showed that the soot of a petroleum-fired vehicle possessed the most potent anti-progesteronic activity, that of coal-fired stove and diesel fired agrimotor emissions took the second place, and soot samples of coal-fired heating work and electric power station had lesser progesterone inhibition activity. The anti-progesteronic activity of APM was between that of soot from petroleum-fired vehicle and soot from coal-fired establishments and diesel fired agrimotor. Since there was no other large pollution source near the APM sampling sites, the endocrine disrupters were most likely from vehicle emissions, tire attrition and house heating sources. The correlation analysis showed that a strong relationship existed between estrogenic activity and anti-progesteronic activity in emissions of fossil fuel combustion. The discoveries that some environmental pollutants with estrogenic activity can also inhibit hPR activity indicate that further studies are required to investigate potential mechanisms for the reported estrogenic activities of these pollutants.

  3. Dietary acrylamide intake and estrogen and progesterone receptor-defined postmenopausal breast cancer risk

    DEFF Research Database (Denmark)

    Pedersen, Grete S; Hogervorst, Janneke G F; Schouten, Leo J

    2010-01-01

    Acrylamide, a potential human carcinogen, has been discovered in a variety of heat-treated carbohydrate-rich food products. Previously, dietary acrylamide intake was shown to be associated with endocrine-related cancers in humans. We assessed the association between dietary acrylamide intake...... breast cancer cases were ascertained, with hormone receptor status information for 43%. Cox proportional hazards analysis was applied to determine hazard ratios in quintiles of dietary acrylamide intake stratifying on estrogen receptor (ER) and progesterone receptor (PR) and smoking status...... ratios were 1.31 (95% CI: 0.87-1.97, P (trend) = 0.26) for ER+, 1.47 (0.86-2.51, P (trend) = 0.14) for PR+, and 1.43 (0.83-2.46, P (trend) = 0.16) for ER+PR+, when comparing women in the highest quintile of acrylamide intake (median 36.8 microg/day) to women in the lowest (median 9.5 microg...

  4. Progesterone and Estrogen Receptors in Neurofibromas of Patients with NF1

    Directory of Open Access Journals (Sweden)

    Mauro Geller

    2008-01-01

    Full Text Available Neurofibromatosis type 1 (NF1 or von Recklinghausen disease is a genetic disorder affecting the growth of cells in nervous system. One of the most remarkable characteristics of this disease is the development of benign tumors of the nervous system (neurofibromas. The purpose of this study was to test tissue samples taken from neurofibromas and plexiform neurofibromas of NF1 patients for the presence of estrogen and progesterone receptors. We used previously collected samples from patients registered in the database of the Centro Nacional de Neurofibromatose (CNNF-Brazil. Samples from twenty-five patients in the database presenting plexiform neurofibromas (N1 group and 25 samples from the same database from patients presenting neurofibromas (N2 group were tested. We observed positive staining for progesterone receptors in 13 of the neurofibroma samples and 19 of the plexiform neurofibroma samples. Among the neurofibroma samples, we observed one sample with positive estrogen receptor staining, but none of the plexiform neurofibroma samples showed positive staining. We suggest further studies to investigate in greater depth possible hormonal influences on the development and growth of neurofibromas and plexiform neurofibromas in NF1.

  5. Reduced hypoxic ventilatory response in newborn mice knocked-out for the progesterone receptor.

    Science.gov (United States)

    Potvin, Catherine; Rossignol, Orlane; Uppari, NagaPraveena; Dallongeville, Arnaud; Bairam, Aida; Joseph, Vincent

    2014-11-01

    Recent studies showed that progesterone stimulates the hypoxic ventilatory response and may reduce apnoea frequency in newborn rats, but so far we still do not know by what mechanisms and whether endogenous progesterone might contribute to respiratory control in neonates. We therefore determined the role of the nuclear progesterone receptor (PR; member of the steroid receptor superfamily) by using wild-type (WT) and PR knock-out (PRKO) mice at postnatal days (P) 1, 4 and 10. We measured the hypoxic ventilatory response (14 and 12% O2, 20 min each) and apnoea frequency in both male and female mice by using whole-body plethysmography. In response to hypoxia, WT male mice had a marked hypoxic ventilatory response at P1 and P10, but not at P4. At P1 and P10, PRKO male mice had a lower hypoxic ventilatory response than WT males. Wild-type female mice had a marked hypoxic ventilatory response at P10, but not at P1 and P4. At P1 and P10, PRKO female mice had a lower hypoxic ventilatory response than WT females. In basal conditions, apnoea frequency was similar in WT and PRKO mice at P1, P4 and P10. During hypoxia, apnoea frequency was higher in WT male mice compared with PRKO male mice and WT female mice at P1. We conclude that PR is a key contributor to the hypoxic ventilatory response in newborn mice, but PR deletion does not increase the frequency of apnoea during normoxia or hypoxia. © 2014 The Authors. Experimental Physiology © 2014 The Physiological Society.

  6. Distinct functions and regulation of epithelial progesterone receptor in the mouse cervix, vagina, and uterus

    Science.gov (United States)

    Mehta, Fabiola F.; Son, Jieun; Hewitt, Sylvia C.; Jang, Eunjung; Lydon, John P.; Korach, Kenneth S.; Chung, Sang-Hyuk

    2016-01-01

    While the function of progesterone receptor (PR) has been studied in the mouse vagina and uterus, its regulation and function in the cervix has not been described. We selectively deleted epithelial PR in the female reproductive tracts using the Cre/LoxP recombination system. We found that epithelial PR was required for induction of apoptosis and suppression of cell proliferation by progesterone (P4) in the cervical and vaginal epithelium. We also found that epithelial PR was dispensable for P4 to suppress apoptosis and proliferation in the uterine epithelium. PR is encoded by the Pgr gene, which is regulated by estrogen receptor α (ERα) in the female reproductive tracts. Using knock−in mouse models expressing ERα mutants, we determined that the DNA−binding domain (DBD) and AF2 domain of ERα were required for upregulation of Pgr in the cervix and vagina as well as the uterine stroma. The ERα AF1 domain was required for upregulation of Pgr in the vaginal stroma and epithelium and cervical epithelium, but not in the uterine and cervical stroma. ERα DBD, AF1, and AF2 were required for suppression of Pgr in the uterine epithelium, which was mediated by stromal ERα. Epithelial ERα was responsible for upregulation of epithelial Pgr in the cervix and vagina. Our results indicate that regulation and functions of epithelial PR are different in the cervix, vagina, and uterus. PMID:27007157

  7. Progesterone Receptor Transcriptome and Cistrome in Decidualized Human Endometrial Stromal Cells

    Science.gov (United States)

    Mazur, Erik C.; Vasquez, Yasmin M.; Li, Xilong; Kommagani, Ramakrishna; Jiang, Lichun; Chen, Rui; Lanz, Rainer B.; Kovanci, Ertug; Gibbons, William E.

    2015-01-01

    Decidualization is a complex process involving cellular proliferation and differentiation of the endometrial stroma that is required to establish and support pregnancy. Progesterone acting via its nuclear receptor, the progesterone receptor (PGR), is a critical regulator of decidualization and is known to interact with certain members of the activator protein-1 (AP-1) family in the regulation of transcription. In this study, we identified the cistrome and transcriptome of PGR and identified the AP-1 factors FOSL2 and JUN to be regulated by PGR and important in the decidualization process. Direct targets of PGR were identified by integrating gene expression data from RNA sequencing with the whole-genome binding profile of PGR determined by chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) in primary human endometrial stromal cells exposed to 17β-estradiol, medroxyprogesterone acetate, and cAMP to promote in vitro decidualization. Ablation of FOSL2 and JUN attenuates the induction of 2 decidual marker genes, IGFBP1 and PRL. ChIP-seq analysis of genomic binding revealed that FOSL2 is bound in proximity to 8586 distinct genes, including nearly 80% of genes bound by PGR. A comprehensive assessment of the PGR-dependent decidual transcriptome integrated with the genomic binding of PGR identified FOSL2 as a potentially important transcriptional coregulator of PGR via direct interaction with regulatory regions of genes actively regulated during decidualization. PMID:25781565

  8. Distinct functions and regulation of epithelial progesterone receptor in the mouse cervix, vagina, and uterus.

    Science.gov (United States)

    Mehta, Fabiola F; Son, Jieun; Hewitt, Sylvia C; Jang, Eunjung; Lydon, John P; Korach, Kenneth S; Chung, Sang-Hyuk

    2016-04-05

    While the function of progesterone receptor (PR) has been studied in the mouse vagina and uterus, its regulation and function in the cervix has not been described. We selectively deleted epithelial PR in the female reproductive tracts using the Cre/LoxP recombination system. We found that epithelial PR was required for induction of apoptosis and suppression of cell proliferation by progesterone (P4) in the cervical and vaginal epithelium. We also found that epithelial PR was dispensable for P4 to suppress apoptosis and proliferation in the uterine epithelium. PR is encoded by the Pgr gene, which is regulated by estrogen receptor α (ERα) in the female reproductive tracts. Using knock-in mouse models expressing ERα mutants, we determined that the DNA-binding domain (DBD) and AF2 domain of ERα were required for upregulation of Pgr in the cervix and vagina as well as the uterine stroma. The ERα AF1 domain was required for upregulation of Pgr in the vaginal stroma and epithelium and cervical epithelium, but not in the uterine and cervical stroma. ERα DBD, AF1, and AF2 were required for suppression of Pgr in the uterine epithelium, which was mediated by stromal ERα. Epithelial ERα was responsible for upregulation of epithelial Pgr in the cervix and vagina. Our results indicate that regulation and functions of epithelial PR are different in the cervix, vagina, and uterus.

  9. The cytoplasmic 60 kDa progesterone receptor isoform predominates in the human amniochorion and placenta at term

    Directory of Open Access Journals (Sweden)

    Bell Stephen C

    2009-03-01

    Full Text Available Abstract Background The mechanism that initiates human parturition has been proposed to be 'functional progesterone withdrawal' whereby the 116 kDa B-isoform of the progesterone receptor (PR-B switches in favour of the 94 kDa A-isoform (PR-A in reproductive tissues. Recently, other PR isoforms, PR-S, PR-C and PR-M generated from the same gene have been identified and partially characterised. Methods and Results Using immunohistochemical, western blotting and RT-PCR techniques, evidence is provided that indicates the major PR isoform present in human term fetal membranes (amnion and chorion and syncytiotrophoblast of the placenta is neither of the classical nuclear PR-B or PR-A isoforms but is the N-terminally truncated 60 kDa PR-C isoform. Evidence is also provided that this 60 kDa isoform resides in the cytoplasm of the expressing cell types. Data are also presented to show that PR-B, PR-A and PR-S isoforms are essentially absent from the amnion and chorion, whereas PR isoforms A, B, C and S are all present in the decidua, with PR-A being the major isoform. The syncytiotrophoblast of the placenta contains the cytoplasmic 60 kDa isoform, but not isoforms PR-A, PR-B or PR-S. Conclusion The major PR isoform in the amnion, chorion and placenta is a 60 kDa protein that could be PR-C, suggesting that the cytoplasmic isoform has a specific role in extra-embryonic tissues and may be involved in the regulation of human parturition.

  10. Sulfhydryl group content of chicken progesterone receptor: effect of oxidation on DNA binding activity

    International Nuclear Information System (INIS)

    Peleg, S.; Schrader, W.T.; O'Malley, B.W.

    1988-01-01

    DNA binding activity of chicken progesterone receptor B form (PRB) and A form (PRA) has been examined. This activity is strongly dependent upon the presence of thiols in the buffer. Stability studies showed that PRB was more sensitive to oxidation that was PRA. Receptor preparations were fractionated by DNA-cellulose chromatography to DNA-positive and DNA-negative subpopulations, and sulfhydryl groups were quantified on immunopurified receptor by labeling with [ 3 H]-N-ethylmaleimide. Labeling of DNA-negative receptors with [ 3 H]-N-ethylmaleimide showed 21-23 sulfhydryl groups on either PRA or PRB form when the proteins were reduced and denatured. A similar number was seen without reduction if denatured DNA-positive receptor species were tested. In contrast, the DNA-negative PRB had only 10-12 sulfhydryl groups detectable without reduction. A similar number (12-13 sulfhydryl groups) was found for PRA species that lost DNA binding activity after exposure to a nonreducing environment in vitro. The authors conclude that the naturally occurring receptor forms unable to bind to DNA, as well as receptor forms that have lost DNA binding activity due to exposure to nonreducing environment in vitro, contain 10-12 oxidized cysteine residues, likely present as disulfide bonds. Since they were unable to reduce the disulfide bonds when the native DNA-negative receptor proteins were treated with dithiothreitol (DTT), they speculate that irreversible loss of DNA binding activity of receptor in vitro is due to oxidation of cysteine residues that are not accessible to DTT in the native state

  11. Progesterone receptor-dependent regulation of genes in the oviducts of female mice.

    Science.gov (United States)

    Akison, Lisa K; Boden, Michael J; Kennaway, David J; Russell, Darryl L; Robker, Rebecca L

    2014-08-15

    Oviducts play a critical role in gamete and embryo transport, as well as supporting early embryo development. Progesterone receptor (PGR) is a transcription factor highly expressed in oviductal cells, while its activating ligand, progesterone, surges to peak levels as ovulation approaches. Progesterone is known to regulate oviduct cilia beating and muscular contractions in vitro, but how PGR may mediate this in vivo is poorly understood. We used PGR null mice to identify genes potentially regulated by PGR in the oviducts during the periovulatory period. Histologically, oviducts from PGR null mice showed no gross structural or morphological defects compared with normal littermates. However, microarray analysis of oviducts at 8 h posthuman chorionic gonadotropin revealed >1,000 PGR-dependent genes. Using reverse-transcription polymerase chain reaction (RT-PCR) we selected 10 genes for validation based on their potential roles in oocyte/embryo transport and support. Eight genes were confirmed to be downregulated (Adamts1, Itga8, Edn3, Prlr, Ptgfr, Des, Myocd, and Actg2) and one upregulated (Agtr2) in PGR null oviducts. Expression of these genes was also assessed in oviducts of naturally cycling mice during ovulation and day 1 and day 4 of pregnancy. Adamts1, Itga8, Edn3, Prlr, and Ptgfr were significantly upregulated in oviducts at ovulation/mating. However, most genes showed basal levels of expression at other times. The exceptions were Prlr and Ptgfr, which showed pulsatile increases on day 1 and/or day 4 of pregnancy. This is the first, comprehensive study to elucidate putative PGR-regulated genes in the oviduct and reveals key downstream targets potentially mediating oocyte and embryo transport. Copyright © 2014 the American Physiological Society.

  12. In vitro and in vivo characterization of a novel nonsteroidal, species-specific progesterone receptor modulator, PRA-910.

    Science.gov (United States)

    Zhang, Z; Lundeen, S G; Slayden, O; Zhu, Y; Cohen, J; Berrodin, T J; Bretz, J; Chippari, S; Wrobel, J; Zhang, P; Fensome, A; Winneker, R C; Yudt, M R

    2007-01-01

    The progesterone receptor (PR) is an important regulator of female reproduction. Consequently, PR modulators have found numerous pharmaceutical utilities in women's reproductive health. In the process of identifying more receptor-specific and tissue-selective PR modulators, we discovered a novel nonsteroidal, 6-aryl benzoxazinone compound, PRA-910, that displays unique in vitro and in vivo activities. In a PR/PRE reporter assay in COS-7 cells, PRA-910 shows potent PR antagonist activity with an IC50 value of approximately 20 nM. In the alkaline phosphatase assay in the human breast cancer cell line T47D, PRA-910 is a partial progesterone antagonist at low concentrations and is also an effective PR agonist at higher concentrations (EC50 value of approximately 700 nM). PRA-910 binds to the human PR with high affinity (Kd = 4 nM) and was previously shown to exhibit greater than 100-fold selectivity for the PR versus other steroid receptors. In the adult ovariectomized rat, PRA-910 is a potent PR antagonist. It inhibits progesterone-induced uterine decidual response with an ED50 value of 0.4 mg/kg, p.o., and reverses progesterone suppression of estradiol-induced complement C3 expression with potency similar to RU-486. In the nonhuman primate, however, PRA-910 is a PR agonist. The effect on endometrial histology strongly resembles that of progesterone. This unique compound also suppresses estradiol-induced epithelial cell proliferation and both estrogen and progesterone receptor expression in the uterine endometrium as a PR agonist would. In summary, PRA-910 is a structurally and biologically novel selective PR modulator with either PR agonist or antagonist activity, depending on context, concentration, and species.

  13. Rodent Models of Non-classical Progesterone Action Regulating Ovulation

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    Melinda A. Mittelman-Smith

    2017-07-01

    Full Text Available It is becoming clear that steroid hormones act not only by binding to nuclear receptors that associate with specific response elements in the nucleus but also by binding to receptors on the cell membrane. In this newly discovered manner, steroid hormones can initiate intracellular signaling cascades which elicit rapid effects such as release of internal calcium stores and activation of kinases. We have learned much about the translocation and signaling of steroid hormone receptors from investigations into estrogen receptor α, which can be trafficked to, and signal from, the cell membrane. It is now clear that progesterone (P4 can also elicit effects that cannot be exclusively explained by transcriptional changes. Similar to E2 and its receptors, P4 can initiate signaling at the cell membrane, both through progesterone receptor and via a host of newly discovered membrane receptors (e.g., membrane progesterone receptors, progesterone receptor membrane components. This review discusses the parallels between neurotransmitter-like E2 action and the more recently investigated non-classical P4 signaling, in the context of reproductive behaviors in the rodent.

  14. Efficient Prediction of Progesterone Receptor Interactome Using a Support Vector Machine Model

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    Ji-Long Liu

    2015-03-01

    Full Text Available Protein-protein interaction (PPI is essential for almost all cellular processes and identification of PPI is a crucial task for biomedical researchers. So far, most computational studies of PPI are intended for pair-wise prediction. Theoretically, predicting protein partners for a single protein is likely a simpler problem. Given enough data for a particular protein, the results can be more accurate than general PPI predictors. In the present study, we assessed the potential of using the support vector machine (SVM model with selected features centered on a particular protein for PPI prediction. As a proof-of-concept study, we applied this method to identify the interactome of progesterone receptor (PR, a protein which is essential for coordinating female reproduction in mammals by mediating the actions of ovarian progesterone. We achieved an accuracy of 91.9%, sensitivity of 92.8% and specificity of 91.2%. Our method is generally applicable to any other proteins and therefore may be of help in guiding biomedical experiments.

  15. Prostaglandin receptors EP and FP are regulated by estradiol and progesterone in the uterus of ovariectomized rats

    Directory of Open Access Journals (Sweden)

    Blesson Chellakkan S

    2012-01-01

    Full Text Available Abstract Background Prostaglandins are important for female reproduction. Prostaglandin-E2 acts via four different receptor subtypes, EP1, EP2, EP3 and EP4 whereas prostaglandin-F2alpha acts through FP. The functions of prostaglandins depend on the expression of their receptors in different uterine cell types. Our aim was to investigate the expression of EPs and FP in rat uterus and to identify the regulation by estradiol, progesterone and estrogen receptor (ER selective agonists. Methods We performed four different rat experiments involving treatments with estradiol, progesterone and ER agonists. Real-time PCR and immunohistochemistry were employed to evaluate receptor expression. Results Our results showed that all mRNAs and proteins of EPs and FP are expressed in the rat uterus. The expression pattern and intensity of immunostaining vary between different cell types and treatments. The mRNA expression of all EPs and FP are downregulated by estradiol and the ERalpha specific agonist PPT, whereas the ERbeta specific agonist DPN downregulates only EP2 and EP4. The protein expression however, showed an increase in EP2 and EP3 after estradiol treatment. When treated with estradiol and progesterone in combination, the expressions of EP1 and EP3 are upregulated. Conclusions Regulation of EPs and FP expression by estradiol appears to be mainly modulated via ERalpha for EP1, EP3 and FP, while EP2 and EP4 also are affected by the ERbeta selective ligand. Our immunohistochemical data shows a cell specific regulation of prostaglandin receptors under the influence of ovarian steroids, where EP2 is estrogen regulated in all uterine tissues examined. EP1 and EP3 are upregulated by the combination of estradiol and progesterone. Thus, our observations indicate that estradiol and progesterone regulate the mRNA and protein expression of EPs and FP in a receptor and tissue specific way.

  16. Expression of oxytocin, progesterone, and estrogen receptors in the reproductive tract of bitches with pyometra.

    Science.gov (United States)

    Prapaiwan, N; Manee-In, S; Olanratmanee, E; Srisuwatanasagul, S

    2017-02-01

    Canine pyometra is considered a serious and life-threatening condition. Due to the relationship among sex steroid hormones, oxytocin receptor (OTR) expression, and canine pyometra pathogenesis, this study aimed to investigate the expression of oxytocin, progesterone, and estrogen receptors in the reproductive tissues of canines with pyometra by real-time PCR and immunohistochemistry. A total of 27 pyometra bitches were classified into open- and closed-cervix pyometra groups based on the presence of vaginal discharge. Moreover, 15 normal bitches in the luteal phase served as a control group. The results showed that OTR gene expression in the ovary of pyometra bitches was higher than that of normal bitches, whereas the level of OTR gene expression in the cervix of pyometra bitches was less than that of normal bitches (P pyometra bitches compared with normal bitches, whereas a higher percentage of OTR-positive immunostaining in uteri and cervices were found in pyometra bitches compared with normal bitches (P pyometra bitches were less than that of normal bitches (P pyometra bitches was not different. Our findings suggest that pyometra pathogenesis is associated with a change in expression of OTR and sex steroid receptors in the canine reproductive tract. However, cervical dilation in bitches with pyometra was not influenced by the expression of OTR and sex steroid receptors. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. ANTAGONISM OF PROGESTERONE RECEPTOR SUPPRESSES CAROTID BODY RESPONSES TO HYPOXIA AND NICOTINE IN RAT PUPS

    Science.gov (United States)

    JOSEPH, V.; NIANE, L. M.; BAIRAM, A.

    2013-01-01

    We tested the hypothesis that antagonism of progesterone receptor (PR) in newborn rats alters carotid body and respiratory responses to hypoxia and nicotinic receptor agonists. Rats were treated with the PR antagonist mifepristone (daily oral gavage 40 μg/g/d) or vehicle between post-natal days 3 and 15. In 11–14-day-old rats, we used in vitro carotid body/carotid sinus nerve preparation and whole body plethysmography to assess the carotid body and ventilatory responses to hypoxia (65 mmHg in vitro, 10% O2 in vivo) and to nicotinic receptor agonists (as an excitatory modulator of carotid body activity—nicotine 100 μM for in vitro studies, and epibatidine 5 μg/kg, i.p., which mainly acts on peripheral nicotinic receptors, for in vivo studies). The carotid body responses to hypoxia and nicotine were drastically reduced by mifepristone. Compared with vehicle, mifepristone-treated rats had a reduced body weight. The ventilatory response to epibatidine was attenuated; however, the hypoxic ventilatory response was similar between vehicle and mifepristone-treated pups. Immunohistochemical staining revealed that mifepristone treatment did not change carotid body morphology. We conclude that PR activity is a critical factor ensuring proper carotid body function in newborn rats. PMID:22326965

  18. New iodinated progestins as potential ligands for progesterone receptor imaging in breast cancer. Part 2: In vivo pharmacological characterization

    NARCIS (Netherlands)

    Rijks, L. J.; van den Bos, J. C.; van Doremalen, P. A.; Boer, G. J.; de Bruin, K.; Janssen, A. G.; van Royen, E. A.

    1998-01-01

    On the basis of the observed high selective binding to both the human and rat progesterone receptor (PR) in vitro, three 17alpha-iodovinyl-substituted nortestosterone derivatives, i.e., the Z-isomer of 17alpha-iodovinyl-19-nortestosterone (Z-IVNT; Z-IPG1) and both the stereoisomers of

  19. Immunohistochemical expression of estrogens and progesterone receptors in carcinoma ex pleomorphic adenoma-undifferentiated and adenocarcinoma types.

    Science.gov (United States)

    Tarakji, Bassel; Nassani, Mohammad Z; Sloan, Philip

    2010-05-01

    Cancer of the salivary gland is one of the common cancers in the head and the neck regions. This type of cancer develops in the minor and the major salivary glands, and it sometimes metastasizes to other organs, particularly the lung. Morphologic mimicry and similarity in the expression of steroid hormone receptors between salivary gland tumours and breast tumours are well-known phenomena and are occasionally debated in the field of surgical pathology. The expression of sex hormone receptors in some tumours suggests a role for these receptors in tumor pathogenesis and therapy. Previous studies of the expression of estrogens and progesterone receptors in salivary gland tumours have reported conflicting results. Our study aimed to characterize alteration in the immunohistochemical expression of oestrogens receptor and progesterone receptor in the tumour cells of carcinoma arising in pleomorphic adenoma. 27 cases of carcinoma arising in pleomorphic adenoma (undifferentiated and adenocarcinoma types) were examined. The results showed that 27 (100 %) of 27 cases had negative nuclear staining for either oestrogens or progesterone receptors. Our data suggest that carcinomas arising in pleomorphic adenoma were not dependent on endocrine function.

  20. Potential contribution of progesterone receptors to the development of sexual behavior in male and female mice.

    Science.gov (United States)

    Desroziers, Elodie; Brock, Olivier; Bakker, Julie

    2017-04-01

    We previously showed that estradiol can have both defeminizing and feminizing effects on the developing mouse brain. Pre- and early postnatal estradiol defeminized the ability to show lordosis in adulthood, whereas prepubertal estradiol feminized this ability. Furthermore, we found that estradiol upregulates progesterone receptors (PR) during development, inducing both a male-and female-typical pattern of PR expression in the mouse hypothalamus. In the present study, we took advantage of a newly developed PR antagonist (ZK 137316) to determine whether PR contributes to either male- or female-typical sexual differentiation. Thus groups of male and female C57Bl/6j mice were treated with ZK 137316 or OIL as control: males were treated neonatally (P0-P10), during the critical period for male sexual differentiation, and females were treated prepubertally (P15-P25), during the critical period for female sexual differentiation. In adulthood, mice were tested for sexual behavior. In males, some minor effects of neonatal ZK treatment on sexual behavior were observed: latencies to the first mount, intromission and ejaculation were decreased in neonatally ZK treated males; however, this effect disappeared by the second mating test. By contrast, female mice treated with ZK during the prepubertal period showed significantly less lordosis than OIL-treated females. Mate preferences were not affected in either males or females treated with ZK during development. Taken together, these results suggest a role for PR and thus perhaps progesterone in the development of lordosis behavior in female mice. By contrast, no obvious role for PR can be discerned in the development of male sexual behavior. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Induction of parturition in the bitch with the progesterone-receptor blocker aglépristone.

    Science.gov (United States)

    Baan, M; Taverne, M A M; Kooistra, H S; de Gier, J; Dieleman, S J; Okkens, A C

    2005-04-15

    The triggering mechanism for parturition in the bitch remains unclear. Consequently, the development of drugs to successfully induce parturition in the dog has been difficult. The aim of this study was to evaluate the efficacy of the progesterone-receptor blocker aglépristone for the induction of parturition in beagle bitches. The course of parturition was therefore investigated in six parturitions induced by aglépristone and in six spontaneous parturitions. In addition, data were collected on pup survival and growth rates. Aglépristone was administered twice with a 9h interval on day 58 of pregnancy. If parturition did not proceed a standard intervention protocol was applied. Expulsion of the first pup occurred between 32 and 56 h after the first treatment with aglépristone, at which time the plasma progesterone concentration was still elevated. Accordingly, the gestation length of the bitches in the induced group (59.5+/-0.2 days) was significantly shorter than that of the spontaneously whelping bitches (62.2+/-0.5 days). The expulsion phase length, the inter-pup interval, the number of puppies born dead, and the number of clinical interventions needed during parturition did not significantly differ between the spontaneously whelping and the induced group. Pup survival and mean birth weights in the two groups did not differ significantly and aglépristone treatment had no significant influence on the growth rates. The results of this study show that aglépristone is an effective drug which can be used safely for the induction of parturition in the dog.

  2. The impact of luteal phase support on endometrial estrogen and progesterone receptor expression: a randomized control trial

    Directory of Open Access Journals (Sweden)

    Brezina Paul R

    2012-02-01

    Full Text Available Abstract Background To assess the impact of luteal phase support on the expression of estrogen receptor (ER alpha and progesterone receptors B (PR-B on the endometrium of oocyte donors undergoing controlled ovarian hyperstimulation (COH. Methods A prospective, randomized study was conducted in women undergoing controlled ovarian hyperstimulation for oocyte donation. Participants were randomized to receive no luteal support, vaginal progesterone alone, or vaginal progesterone plus orally administered 17 Beta estradiol. Endometrial biopsies were obtained at 4 time points in the luteal phase and evaluated by tissue microarray for expression of ER alpha and PR-B. Results One-hundred and eight endometrial tissue samples were obtained from 12 patients. No differences were found in expression of ER alpha and PR-B among all the specimens with the exception of one sample value. Conclusions The administration of progesterone during the luteal phase of COH for oocyte donor cycles, either with or without estrogen, does not significantly affect the endometrial expression of ER alpha and PR.

  3. Progesterone and levonorgestrel regulate expression of 17βHSD-enzymes in progesterone receptor positive breast cancer cell line T47D.

    Science.gov (United States)

    Sivik, Tove; Jansson, Agneta

    2012-05-25

    The use of combined hormone replacement therapy (HRT) with oestrogens and progestins in postmenopausal women has been associated with an increased risk for developing breast cancer. The reasons are not fully understood, but influence of HRT on endogenous conversion of female sex hormones may be involved. The expression of 17β hydroxysteroid dehydrogenases (17βHSD), which are enzymes catalysing the conversion between more or less potent oestrogens, may partly be regulated by progestins. The breast cancer cell lines T47D, MCF7 and ZR75-1 were treated with progesterone, medroxyprogesterone acetate (MPA) or levonorgestrel for 48 and 72 h at 10(-7) and 10(-9)M to investigate influence on 17βHSD1, 17βHSD2 and 17βHSD5 mRNA expression measured by real time PCR. The expression of 17βHSD1 increased in progesterone and levonorgestrel treated T47D cells (48 h 10(-7)M P=0.002; PT47D cells were co-treated with progestins and the progesterone receptor (PgR) inhibitor mifprestone. We show that both reductive (17βHSD1 and 17βHSD5) and oxidative (17βHSD2) members of the 17βHSD-family are under control of progesterone and progestins in breast cancer cell lines. This is most clear in T47D cells which have high PgR expression. 17βHSD-enzymes are important players in the regulation of sex steroids locally in breast tumours and tumoural expression of various 17βHSD-enzymes have prognostic and treatment predictive relevance. We propose a mechanism for increased breast cancer risk after HRT in which hormone replacement affects the expression of 17βHSD-enzymes, favouring the expression of reductive enzymes, which in turn could increase levels of bioactive and mitogenic estrogens in local tissue, e.g. breast tissue. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. [The expression assessment of the estrogen, progesterone and HER2 receptors in selected malignant tumors of the salivary glands].

    Science.gov (United States)

    Golusiński, Wojciech; Wegner, Anna; Trzeciak, Paweł; Golusiński, Paweł; Sówka, Marcin; Kopczyński, Andrzej; Bromboszcz, Małgorzata; Marszałek, Andrzej

    2013-01-01

    The incidence of the malignant tumors of the salivary glands is relatelively low. However, rapid locoregional progression, distant metastases occurrence and high local recurrence rate occurring despite radical surgical treatment, significantly affect the outcome. Malignant tumors of the salivary glands are characterized by low radiosensitivity and poor response to systemic therapy. Therefore there is a need for new targeted therapies which may improve the prognosis. In some aspects, malignant tumors of the salivary glands are similar to breast cancers. Efficacy of hormonal replacement therapy and the treatment with the monoclonal antibody (trastuzumab) in the treatment of breast cancer is well known and confirmed. Criterion determining the qualification for treatment is the presence of hormone receptors and HER2 receptors in the tumor. The aim of this study was to evaluate the expression of estrogen receptor, progesterone receptor and HER2 in selected salivary gland malignancies. Study group consisted of 51 patients with the salivary glands cancer. In the study group there were 42 tumors in the parotid gland, 7 tumors of the submandibular gland, 1 in the mucosa of the cheek and 1 tumor in the tongue. Histologically material comprised of muco-epidermoid carcinoma (10), adenoid-cystic carcinoma (8), salivary duct (7), adenocarcinoma (6), squamous cell carcinoma (6), mioepithelial carcinoma (5) and other (9). In all cases immunohistochemical analysis of the estrogen receptor, progesterone receptor and HER2 receptor was performed. The expression of the estrogen receptor was found in 18% of tumors (9 patients). The expression of the progesterone receptor was found in 20% (10 patients). HER2 expression was found in 10% of tumors and was related to only one histological type of tumor - salivary duct carcinoma. HER2 expression in malignant tumors of the salivary glands, especially in salivary duct carcinoma may be of use in future implementation of new targeted therapies

  5. The effects of black cohosh on the regulation of estrogen receptor (ERα and progesterone receptor (PR in breast cancer cells

    Directory of Open Access Journals (Sweden)

    Szmyd M

    2018-01-01

    Full Text Available Monica Szmyd,1–3 Victoria Lloyd,1–3 Kelly Hallman,1–3 Katie Aleck,1–3 Viktoria Mladenovik,1–3 Christina McKee,1–3 Mia Morse,1–3 Tyler Bedgood,1–3 Sumi Dinda1–3 1Biomedical and Therapeutic Sciences, School of Health Sciences, 2Prevention Research Center, 3Center of Biomedical Sciences, Oakland University, Rochester, MI, USA Abstract: The North American plant Cimicifuga racemosa, also known as black cohosh (BC, is a herb that recently has gained attention for its hormonal effects. As the usage of hormone replacement therapy is declining due to its adverse effects in women with cancer, many are turning to herbal remedies like BC to treat menopausal symptoms. It is crucial to determine whether the effects of BC involve estrogen receptor-alpha (ERα. Previous studies from our laboratory have shown ERα to be a possible molecular target for BC. In this study, we examined the effects of BC (8% triterpene glycosides alone and in combination with hormones and antihormones on the cellular viability, expression of ERα and progesterone receptor (PR-A/B, and cytolocalization of ERα in ER (+ and PR-A/B (+ T-47D breast cancer cells. Cells were cultured and proteins were extracted and quantified. Western blot analysis revealed alterations in the expression of ERα and PR after treatment with BC (5–100 µM. BC induced a concentration-dependent decrease in ERα and PR protein levels when compared to the control. Image cytometric analysis with propidium iodide staining was used to enumerate changes in T-47D cell number and viability. A decrease in T-47D cell viability was observed upon treatment with 5–100 µM BC. The ideal concentration of BC (100 μM was used in combination with hormones and antihormones in an effort to further understand the possible similarities between this compound and other known effectors of ERα and PR. After a 24-hour concomitant treatment with and/or in combination of BC, estradiol, ICI 182, 780, and Tamoxifen

  6. Spontaneous feline mammary intraepithelial lesions as a model for human estrogen receptor- and progesterone receptor-negative breast lesions

    International Nuclear Information System (INIS)

    Burrai, Giovanni P; Mohammed, Sulma I; Miller, Margaret A; Marras, Vincenzo; Pirino, Salvatore; Addis, Maria F; Uzzau, Sergio; Antuofermo, Elisabetta

    2010-01-01

    Breast cancer is the most frequently diagnosed cancer in women. Intraepithelial lesions (IELs), such as usual ductal hyperplasia (UH), atypical ductal hyperplasia (ADH), and ductal carcinoma in situ (DCIS) are risk factors that predict a woman's chance of developing invasive breast cancer. Therefore, a comparative study that establishes an animal model of pre-invasive lesions is needed for the development of preventative measures and effective treatment for both mammary IELs and tumors. The purpose of this study was to characterize the histologic and molecular features of feline mammary IELs and compare them with those in women. Formalin-fixed, paraffin-embedded specimens (n = 205) from 203 female cats with clinical mammary disease were retrieved from the archives of the Purdue University Animal Disease Diagnostic Laboratory and Veterinary Teaching Hospital (West Lafayette, IN), and the Department of Pathology and Veterinary Clinic, School of Veterinary Medicine (Sassari, Italy). Histologic sections, stained with hematoxylin and eosin (HE), were evaluated for the presence of IELs in tissue adjacent to excised mammary tumors. Lesions were compared to those of humans. Immunohistochemistry for estrogen receptor (ER-alpha), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2/neu) and Ki-67 was performed in IELs and adjacent tumor tissues. Intraepithelial lesions were found in 57 of 203 (28%) feline mammary specimens and were categorized as UH (27%), ADH (29%), and DCIS (44%). Most IELs with atypia (ADH and DCIS) were associated with mammary cancer (91%), whereas UH was associated with benign lesions in 53% of cases. Feline IELs were remarkably similar to human IELs. No ER or PR immunoreactivity was detected in intermediate-grade or high-grade DCIS or their associated malignant tumors. HER-2 protein overexpression was found in 27% of IELs. The remarkable similarity of feline mammary IELs to those of humans, with the tendency to lose hormone

  7. Provision of a simplified methodology for determining estradiol and progesterone receptors in human breast tumours. Internal and external quality control

    International Nuclear Information System (INIS)

    Farinate, Z.

    1990-10-01

    A simplified assay for the detection of progesterone receptors (PR) in human breast tissue is described. Tissue storage is at -20 deg. C rather than -70 deg. C and a centrifugation speed of 20,000 rpm avoids requirement of an ultracentrifuge. Cytosol preparations obtained from homogenized oestradiol benzoate primed wistar rat uteri performed satisfactorily as positive controls with stability of two months in liquid nitrogen. The use of iodinated tracer (progesterone 11 alpha glucuronide 125 I iodotyramine) proved disappointing in the progesterone receptor assay in contrast to 125 I oestradiol which worked well in a oestrogen receptor assay, previously developed. Hydroxyl-apatite was a better separating agent than dextran coated charcoal in both assays and yielded better sensitivity, particularly when protein concentrations were low. Five breast cancer specimens assayed yielded, by Scatchard analysis, Kd values between 12 to 22x10 -9 m|h, comparable to the positive controls. However, two of these had binding site capacity of less than 5 fmol/mg cytosol as compared to the three others and the positive controls where values ranged from 47-196 fmol/mg cytosol. 28 refs, 6 figs, 14 tabs

  8. Deep sequencing reveals new aspects of progesterone receptor signaling in breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Anastasia Kougioumtzi

    Full Text Available Despite the pleiotropic effects of the progesterone receptor in breast cancer, the molecular mechanisms in play remain largely unknown. To gain a global view of the PR-orchestrated networks, we used next-generation sequencing to determine the progestin-regulated transcriptome in T47D breast cancer cells. We identify a large number of PR target genes involved in critical cellular programs, such as regulation of transcription, apoptosis, cell motion and angiogenesis. Integration of the transcriptomic data with the PR-binding profiling of hormonally treated cells identifies numerous components of the small-GTPases signaling pathways as direct PR targets. Progestin-induced deregulation of the small GTPases may contribute to the PR's role in mammary tumorigenesis. Transcript expression analysis reveals significant expression changes of specific transcript variants in response to the extracellular hormonal stimulus. Using the NET1 gene as an example, we show that the PR can dictate alternative promoter usage leading to the upregulation of an isoform that may play a role in metastatic breast cancer. Future studies should aim to characterize these selectively regulated variants and evaluate their clinical utility in prognosis and targeted therapy of hormonally responsive breast tumors.

  9. Clinical utility of progesterone receptor modulators and their effect on the endometrium.

    Science.gov (United States)

    Spitz, Irving M

    2009-08-01

    In view of the spate of recent publications related to mifepristone and some second generation progesterone receptor modulators (PRMs), this appears to be an opportune time to view the clinical status of these compounds. Randomized double-blind placebo-controlled trials have been conducted with mifepristone, CDB-4124 (Proellex), CDB-2914 (VA 2914, Ulipristal) and asoprisnil (J867). All these PRMs are effective in the treatment of uterine fibroids where they are associated with a reduction in pain, bleeding and improvement in quality of life and decrease in fibroid size. CDB-4124 is also efficacious in endometriosis. Long-term treatment with PRMs may be associated with endometrial thickening on ultrasound and there have been reports of endometrial hyperplasia. Several reassuring recent publications have done much to explain the mechanism underlying these endometrial changes. The most common histological finding is cystic glandular dilatation often associated with both admixed estrogen (mitotic) and progestin (secretory) epithelial effects. This histology has not been previously encountered in clinical practice and should not be confused with endometrial hyperplasia. The endometrial thickness is related to this cystic glandular dilatation. At this stage of development, PRMs cannot be administered for longer than 3 or 4 months. Even over this time, there is improvement of symptoms associated with fibroids and endometriosis. Clinicians and pathologists need to be aware that the endometrial thickening and histological appearance do not represent endometrial hyperplasia.

  10. The chromatin Remodeler CHD8 is required for activation of progesterone receptor-dependent enhancers.

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    María Ceballos-Chávez

    2015-04-01

    Full Text Available While the importance of gene enhancers in transcriptional regulation is well established, the mechanisms and the protein factors that determine enhancers activity have only recently begun to be unravelled. Recent studies have shown that progesterone receptor (PR binds regions that display typical features of gene enhancers. Here, we show by ChIP-seq experiments that the chromatin remodeler CHD8 mostly binds promoters under proliferation conditions. However, upon progestin stimulation, CHD8 re-localizes to PR enhancers also enriched in p300 and H3K4me1. Consistently, CHD8 depletion severely impairs progestin-dependent gene regulation. CHD8 binding is PR-dependent but independent of the pioneering factor FOXA1. The SWI/SNF chromatin-remodelling complex is required for PR-dependent gene activation. Interestingly, we show that CHD8 interacts with the SWI/SNF complex and that depletion of BRG1 and BRM, the ATPases of SWI/SNF complex, impairs CHD8 recruitment. We also show that CHD8 is not required for H3K27 acetylation, but contributes to increase accessibility of the enhancer to DNaseI. Furthermore, CHD8 was required for RNAPII recruiting to the enhancers and for transcription of enhancer-derived RNAs (eRNAs. Taken together our data demonstrate that CHD8 is involved in late stages of PR enhancers activation.

  11. [The progesterone receptor gene polymorphism as factor of risk for the preterm delivery].

    Science.gov (United States)

    Oliveira, Tenilson Amaral; da Cunha, Danielle Renzoni; Policastro, Adriana; Traina, Évelyn; Gomes, Mariano Tamura; Cordioli, Eduardo

    2011-06-01

    to investigate the association between gene polymorphism of the progesterone receptor (PROGINS) and the risk of premature birth. In this case-control study, 57 women with previous premature delivery (Case Group) and 57 patients with delivery at term in the current pregnancy and no history of preterm delivery (Control Group) were selected. A 10 mL amount of peripheral blood was collected by venipuncture and genomic DNA was extracted followed by the polymerase chain reaction (PCR) under specific conditions for this polymorphism and 2% agarose gel electrophoresis. The bands were visualized with an ultraviolet light transilluminator. Genotype and allele PROGINS frequencies were compared between the two groups by the χ2 test, with the level of significance set at value p < 0.05. The Odds Ratio (OR) was also used, with 95% confidence intervals. PROGINS genotypic frequencies were 75.4% T1/T1, 22.8% T1/T2 and 1.8% T2/T2 in the Group with Preterm Delivery and 80.7% T1/T1, 19.3% T1/T2 and 0% T2/T2 in the term Delivery Group. There were no differences between groups when genotype and allele frequencies were analyzed: p = 0.4 (OR = 0.7) and p = 0.4 (OR = 0.7). the present study suggests that the presence of PROGINS polymorphism in our population does not constitute a risk factor for premature birth.

  12. SAR studies of 6-aryl-1,3-dihydrobenzimidazol-2-ones as progesterone receptor antagonists.

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    Terefenko, Eugene A; Kern, Jeffrey; Fensome, Andrew; Wrobel, Jay; Zhu, Yuan; Cohen, Jeffrey; Winneker, Richard; Zhang, Zhiming; Zhang, Puwen

    2005-08-01

    We have previously reported that the aryl substituted benzimidazolones, benzoxazinones, and oxindoles (e.g., 1-3) are progesterone receptor (PR) antagonists and have recently disclosed that the nature of 5- and 6-aryl moieties played a critical role in PR functional activity in the oxindole and benzoxazinone templates. For example, replacing the phenyl group of PR antagonists 2 and 3 with a 5'-cyanopyrrol-2'-yl moiety switched their functional activity to PR agonist activity (2a and 3a). These findings prompted us to examine if there is a similar effect of the 6-aryl moieties on the PR functional activity for the benzimidazolone template. Numerous analogs, such as 5, showed potent PR antagonist activity with about a 10-fold increase in potency as compared to those reported earlier in the same series. More interestingly, pyrrole-containing benzimidazolones 24-27 remained as PR antagonists in contrast to the PR agonist activity switch for oxindole and benzoxazinone scaffolds when a 5'-cyanopyrrol-2'-yl group was installed as a pendant aryl group.

  13. Expression and Clinical Significance of Progesterone and Adiponectin Receptor Family Member 3 in Lung Cancer

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    Xiaohui LIANG

    2017-04-01

    Full Text Available Background and objective Progesterone and adiponectin receptor family member 3 (PAQR3 is a recently discovered tumor suppressor gene, which affects the development of a tumor by inhibiting cell proliferation, cell malignant transformation, angiogenesis, and tumor metastasis. This study investigates the expression of PAQR3 in lung cancer and its clinical significance. Methods A total of 106 patients with lung cancer received surgical treatment in hospital, and adjacent normal tissues of these patients were utilized as control group. The diagnosis of all patients was confirmed through clinical pathology. The expression of PAQR3 protein was detected by immunohistochemistry in lung cancer and adjacent normal tissues. The clinical significance of its expression was also investigated. Results The positive expression rate of PAQR3 protein in lung cancer was lower than that in adjacent normal tissues (P<0.01. The positive expression rate of PAQR3 protein was unrelated to age, tumor size, and gender, but it exhibited a significant relationship with the pathological type and differentiation, TNM staging, and lymph node metastasis (P<0.05. Kaplan-Meier survival analysis showed that the five-year survival rate of patients with PAQR3 protein positive expression was higher than that in patients with negative expression (P=0.026. Conclusion The expression of PAQR3 protein significantly decreased in lung cancer, indicating that PAQR3 protein plays an important role in the pathogenesis of PAQR3 in lung cancer.

  14. Progesterone receptor (PR) isoforms PRA and PRB differentially regulate expression of the breast cancer resistance protein in human placental choriocarcinoma BeWo cells.

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    Wang, Honggang; Lee, Eun-Woo; Zhou, Lin; Leung, Peter C K; Ross, Douglas D; Unadkat, Jashvant D; Mao, Qingcheng

    2008-03-01

    Breast cancer resistance protein (BCRP) plays a significant role in drug disposition and in conferring multidrug resistance in cancer cells. Previous studies have shown that steroid hormones such as 17beta-estradiol and progesterone can affect BCRP expression in cancer cells. In this study, we investigated the molecular mechanism by which BCRP expression in human placental choriocarcinoma BeWo cells is regulated by progesterone. Transfection of the progesterone receptor (PR) isoforms PRA and PRB resulted in a similarly increased expression of PRA and PRB, respectively. However, progesterone significantly increased BCRP expression and activity only in PRB-transfected cells. This stimulatory effect of progesterone was abrogated by the PR antagonist mifepristone (RU-486). Consistently, transcriptional activity of the BCRP promoter was induced 2- to 6-fold by 10(-8) to 10(-5) M progesterone in PRB-transfected cells. Progesterone had little effect on BCRP expression and activity and transcriptional activity of the BCRP promoter in PRA-transfected cells; however, cotransfection of PRA and PRB significantly decreased the progesterone-response compared with that in cells transfected with only PRB. Mutations in a novel progesterone response element (PRE) identified between -243 to -115 bp of the BCRP promoter region significantly attenuated the progesterone-response in PRB-transfected cells, and deletion of the PRE nearly completely abrogated the progesterone effect. Specific binding of both PRA and PRB to the BCRP promoter through the identified PRE was confirmed using the electrophoretic mobility shift assay. Collectively, progesterone induces BCRP expression in BeWo cells via PRB but not PRA. PRA represses the PRB activity. Thus, PRA and PRB differentially regulate BCRP expression in BeWo cells.

  15. Expression of prostate apoptosis response (Par-4) is associated with progesterone receptor in breast cancer.

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    Zapata-Benavides, Pablo; Méndez-Vázquez, José L; González-Rocha, Talina R; Zamora-Avila, Diana E; Franco-Molina, Moises A; Garza-Garza, Raúl; Rodriguez-Padilla, Cristina

    2009-10-01

    The prostate apoptosis response (Par-4) gene encodes a proapoptotic protein that selectively induces apoptosis in cancer cells after diverse apoptotic stimuli. Par-4 expression and its association with other biomarkers have not been reported in breast cancer. The purpose of this study was to determine Par-4 expression in breast cancer samples and its association with other biomarkers and clinical factors (T-stage, age, nodal status). Paraffin-embedded section samples of breast cancer were evaluated by immunohistochemical analysis to determine Par-4, estrogen receptor (ER), progesterone receptor (PgR), c-erbB2, Ki67, p53 and bcl-2 expression. The correlation between Par-4 and the other biomarkers and clinical factors was determined by multivariate analysis. Thirty five percent (n=21) of samples were PAR-4 positive and 64.4% (n=38) were negative. The hormonal status was 64% ER positive (n=38), 35% ER-negative (n=21) and 40.7% PgR positive (n=24), 59.3% PgR negative (n=35). The majority (90%) of the samples presented clear cytoplasmic localization and a small portion (10%) was cytoplasmic and nuclear. Univariate analysis indicates that the Par-4 expression has a significant inverse association (p=0.04) only with expression of PgR and not with the other variables analyzed. Normal breast tissue analyzed was negative for Par-4 immunostaining. Our results suggest that, in breast cancer, Par-4 plays a similar tumor suppressor gene role as reported in endometrial carcinoma. 2009. Published by Elsevier Inc.

  16. Bioinformatic analysis of cis-regulatory interactions between progesterone and estrogen receptors in breast cancer

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    Matloob Khushi

    2014-11-01

    Full Text Available Chromatin factors interact with each other in a cell and sequence-specific manner in order to regulate transcription and a wealth of publically available datasets exists describing the genomic locations of these interactions. Our recently published BiSA (Binding Sites Analyser database contains transcription factor binding locations and epigenetic modifications collected from published studies and provides tools to analyse stored and imported data. Using BiSA we investigated the overlapping cis-regulatory role of estrogen receptor alpha (ERα and progesterone receptor (PR in the T-47D breast cancer cell line. We found that ERα binding sites overlap with a subset of PR binding sites. To investigate further, we re-analysed raw data to remove any biases introduced by the use of distinct tools in the original publications. We identified 22,152 PR and 18,560 ERα binding sites (<5% false discovery rate with 4,358 overlapping regions among the two datasets. BiSA statistical analysis revealed a non-significant overall overlap correlation between the two factors, suggesting that ERα and PR are not partner factors and do not require each other for binding to occur. However, Monte Carlo simulation by Binary Interval Search (BITS, Relevant Distance, Absolute Distance, Jaccard and Projection tests by Genometricorr revealed a statistically significant spatial correlation of binding regions on chromosome between the two factors. Motif analysis revealed that the shared binding regions were enriched with binding motifs for ERα, PR and a number of other transcription and pioneer factors. Some of these factors are known to co-locate with ERα and PR binding. Therefore spatially close proximity of ERα binding sites with PR binding sites suggests that ERα and PR, in general function independently at the molecular level, but that their activities converge on a specific subset of transcriptional targets.

  17. Ligand-Dependent Degradation of SRC-1 Is Pivotal for Progesterone Receptor Transcriptional Activity

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    Amazit, Larbi; Roseau, Audrey; Khan, Junaid A.; Chauchereau, Anne; Tyagi, Rakesh K.; Loosfelt, Hugues; Leclerc, Philippe; Lombès, Marc

    2011-01-01

    The progesterone receptor (PR), a ligand-activated transcription factor, recruits the primary coactivator steroid receptor coactivator-1 (SRC-1) gene promoters. It is known that PR transcriptional activity is paradoxically coupled to its ligand-dependent down-regulation. However, despite its importance in PR function, the regulation of SRC-1 expression level during hormonal exposure is poorly understood. Here we report that SRC-1 expression level (but not other p160 family members) is down-regulated by the agonist ligand R5020 in a PR-dependent manner. In contrast, the antagonist RU486 fails to induce down-regulation of the coactivator and impairs PR agonist-dependent degradation of SRC-1. We show that SRC-1 proteolysis is a proteasome- and ubiquitin-mediated process that, predominantly but not exclusively, occurs in the cytoplasmic compartment in which SRC-1 colocalizes with proteasome antigens as demonstrated by confocal imaging. Moreover, SRC-1 was stabilized in the presence of leptomycin B or several proteasomal inhibitors. Two degradation motifs, amino-acids 2–16 corresponding to a PEST motif and amino acids 41–136 located in the basic helix loop helix domain of the coactivator, were identified and shown to control the stability as well as the hormone-dependent down-regulation of the coactivator. SRC-1 degradation is of physiological importance because the two nondegradable mutants that still interacted with PR as demonstrated by coimmunoprecipitation failed to stimulate transcription of exogenous and endogenous target genes, suggesting that concomitant PR/SRC-1 ligand-dependent degradation is a necessary step for PR transactivation activity. Collectively our findings are consistent with the emerging role of proteasome-mediated proteolysis in the gene-regulating process and indicate that the ligand-dependent down-regulation of SRC-1 is critical for PR transcriptional activity. PMID:21273440

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

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

    2016-06-01

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

  19. Immunohistochemical features of progesterone receptors expression of placental barrier in women with multiple pregnancies resulting from assisted reproduction

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    T. D. Zadorozhna

    2016-01-01

    Full Text Available Hormonal disorders are one of the main known causes of miscarriage and preterm birth in multiple pregnancies resulting from assisted reproductive technology (ART. Progesterone and the number of its receptors play an important role in the preservation and prolongation of pregnancy and it is the pressing issue of our time. The study of placentas, as the main site of synthesis of progesterone, has high informative potential and it is the most important diagnostic object, and information received by its research is essential for the full conclusion on the causes, mechanisms, close and long-term effects of multiple pregnancy pathology. Aim. The aim of our study was to investigate immunohistochemical features of placentas from women with dichorionic diamniotic twin pregnancies in spontaneous fertilization and after use of assisted reproductive technology (ART. Methods and results. According to this goal we examined 94 women, 44 of whom had multiple pregnancies due to ART, 42 with separate multiple pregnancy and 38 women with a singleton pregnancy. We carried out clinical and statistical analysis of the course of pregnancy and childbirth in the studied groups. During the study it was found that multiple pregnancies due to assisted reproduction belong to the high risk of gestation, at which premature births occur much more frequently than in singleton pregnancies. We were the first to carry out the immunohistochemical study of placentas in which the highest expression of progesterone receptors in the nuclei of cells of decidua (45% related to the parent structure of the placenta from women with multiple pregnancies caused by ART is found. It is also found that with increasing gestational age, there has been a significant decrease in the expression of the activity of progesterone receptors (from 45 to 2.5%, regardless of the method of conception and the number of fetuses. Conclusions. The results of the study point to the definitive link of structures of

  20. The effects of black cohosh on the regulation of estrogen receptor (ERα) and progesterone receptor (PR) in breast cancer cells.

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    Szmyd, Monica; Lloyd, Victoria; Hallman, Kelly; Aleck, Katie; Mladenovik, Viktoria; McKee, Christina; Morse, Mia; Bedgood, Tyler; Dinda, Sumi

    2018-01-01

    The North American plant Cimicifuga racemosa , also known as black cohosh (BC), is a herb that recently has gained attention for its hormonal effects. As the usage of hormone replacement therapy is declining due to its adverse effects in women with cancer, many are turning to herbal remedies like BC to treat menopausal symptoms. It is crucial to determine whether the effects of BC involve estrogen receptor-alpha (ERα). Previous studies from our laboratory have shown ERα to be a possible molecular target for BC. In this study, we examined the effects of BC (8% triterpene glycosides) alone and in combination with hormones and antihormones on the cellular viability, expression of ERα and progesterone receptor (PR)-A/B, and cytolocalization of ERα in ER (+) and PR-A/B (+) T-47D breast cancer cells. Cells were cultured and proteins were extracted and quantified. Western blot analysis revealed alterations in the expression of ERα and PR after treatment with BC (5-100 µM). BC induced a concentration-dependent decrease in ERα and PR protein levels when compared to the control. Image cytometric analysis with propidium iodide staining was used to enumerate changes in T-47D cell number and viability. A decrease in T-47D cell viability was observed upon treatment with 5-100 µM BC. The ideal concentration of BC (100 µM) was used in combination with hormones and antihormones in an effort to further understand the possible similarities between this compound and other known effectors of ERα and PR. After a 24-hour concomitant treatment with and/or in combination of BC, estradiol, ICI 182, 780, and Tamoxifen, downregulation of ERα and PR protein levels was observed. Delineating the role of BC in the regulation of ERα, PR, as well as its mechanisms of action, may be important in understanding the influence of BC on hormone receptors in breast cancer.

  1. A review of the endometrial histologic effects of progestins and progesterone receptor modulators in reproductive age women.

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    Dinh, Anh; Sriprasert, Intira; Williams, Alistair R; Archer, David F

    2015-05-01

    This review compares the histologic changes that occur in the endometrium following ovulation and progesterone secretion with contraceptive progestins and progesterone receptor modulators (PRMs) that may be used as contraceptive agents in women. The morphologic endometrial changes vary by the progestin type, dosage and duration; are often subtle and difficult to interpret; and may also vary depending on whether or not estrogen is used. The prolonged use of ethinyl estradiol and a progestin as a combined oral contraceptive results in common endometrial histologic findings that include glandular and stromal atrophy and spiral arteriole underdevelopment. Intrauterine systems releasing levonorgestrel have similar changes that are related to the proximity of the device to the endometrium, while progestin-only implants result in atrophy with marked vascular changes characterized by underdevelopment of spiral arterioles and dilated, thin-walled vessels near the surface epithelium. Lower doses of levonorgestrel delivered by a vaginal ring allow ovulation, and the endometrial changes appear to reflect the impact of the endogenous hormones. PRMs have been investigated as potential female contraceptives. PRM-associated endometrial changes include an inactive endometrium with cystically dilated glands, lined by epithelium with increased apoptosis in a background of compact nondecidualized stroma. Histologic differences between PRMs appear to depend on the degree of progesterone receptor agonistic activity. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Ulipristal Acetate Inhibits Progesterone Receptor Isoform A-Mediated Human Breast Cancer Proliferation and BCl2-L1 Expression.

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    Nathalie Esber

    Full Text Available The progesterone receptor (PR with its isoforms and ligands are involved in breast tumorigenesis and prognosis. We aimed at analyzing the respective contribution of PR isoforms, PRA and PRB, in breast cancer cell proliferation in a new estrogen-independent cell based-model, allowing independent PR isoforms analysis. We used the bi-inducible human breast cancer cell system MDA-iPRAB. We studied the effects and molecular mechanisms of action of progesterone (P4 and ulipristal acetate (UPA, a new selective progesterone receptor modulator, alone or in combination. P4 significantly stimulated MDA-iPRA expressing cells proliferation. This was associated with P4-stimulated expression of the anti-apoptotic factor BCL2-L1 and enhanced recruitment of PRA, SRC-1 and RNA Pol II onto the +58 kb PR binding motif of the BCL2-L1 gene. UPA decreased cell proliferation and repressed BCL2-L1 expression in the presence of PRA, correlating with PRA and SRC1 but not RNA Pol II recruitment. These results bring new information on the mechanism of action of PR ligands in controlling breast cancer cell proliferation through PRA in an estrogen independent model. Evaluation of PR isoforms ratio, as well as molecular signature studies based on PRA target genes could be proposed to facilitate personalized breast cancer therapy. In this context, UPA could be of interest in endocrine therapy. Further confirmation in the clinical setting is required.

  3. Comparison of Radiologic Features of Triple-Negative and Estrogen Receptor/Progesteron Receptor Positive Breast Cancer

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    Kim, Young Joong; Kim, Keum Won; Kim, Dae Ho; Cho, Yong Jun; Hwang, Cheol Mog; Seo, Jae Young; Kim, Jin Suk; Yoon, Dae Sung [Dept. of Konyang University College of Medicine, Konyang University Hospital, Daejeon (Korea, Republic of); Kim, Gyu Soon [Dept. of Radiology, Eulji University College of Medicine, Eulji University Hospital, Daejeon (Korea, Republic of)

    2013-06-15

    To retrospectively investigate the imaging [mammographic, ultrasonographic (US), magnetic resonance (MR) imaging] features and standardized uptake values (SUV) in positron emission tomography (PET)/computed tomography (CT) of triple-negative breast cancers (TNBC) and to compare them with breast cancers that are either estrogen receptor (ER) positive or progesteron receptor (PR) positive. 155 breast cancers cases were identified in 134 women (mean age, 51 years; range, 31-86 years). Surgically confirmed TNBC (n = 27) and ER-positive/PR-positive breast cancers (n = 81) were included among them. Cancers were investigated with mammography (n = 81), US (n = 106), MR imaging (n = 34) and PET-CT (n = 59). Mammographic findings are identified by detection of characteristic masses and microcalcifications. US findings included tumor size, margin, tumor shape, calcification and posterior shadowing. MR findings included tumor size, shape, margin, internal enhancement, intratumoral signal intensity and kinetics. Peak SUVs (p-SUV) of breast cancers were evaluated in PET/CT. These findings were compared with TNBC and ER/PR positive groups. Mammographic findings had no significant association with the TNBC. High pathological grade (p < 0.05), larger than 2 cm in size, well-marginal mass, and round or oval-shaped (p < 0.05) is US were significantly associated with TNBC. In MR imaging, round mass shape (p < 0.05), well-circumscribed mass margin (p < 0.05), rim enhancement (p < 0.05), were significantly associated with TNBC. The peak SUV of TNBC tend to be higher than that of ER-positive/PR-positive breast cancer (7.95 {+-} 5.50 vs. 4.91 {+-} 3.00, p < 0.05). TNBC tend to have high pathological grade, are of a large, round and smooth mass with rim enhancement on MR and US. In addition to above features, PET-CT with SUV estimation can improve the accuracy of test through the evaluation of TNBC.

  4. Prostate stromal cells express the progesterone receptor to control cancer cell mobility.

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    Yue Yu

    Full Text Available Reciprocal interactions between epithelium and stroma play vital roles for prostate cancer development and progression. Enhanced secretions of cytokines and growth factors by cancer associated fibroblasts in prostate tumors create a favorable microenvironment for cancer cells to grow and metastasize. Our previous work showed that the progesterone receptor (PR was expressed specifically in prostate stromal fibroblasts and smooth muscle cells. However, the expression levels of PR and its impact to tumor microenvironment in prostate tumors are poorly understood.Immunohistochemistry assays are applied to human prostate tissue biopsies. Cell migration, invasion and proliferation assays are performed using human prostate cells. Real-time PCR and ELISA are applied to measure gene expression at molecular levels.Immunohistochemistry assays showed that PR protein levels were decreased in cancer associated stroma when compared with paired normal prostate stroma. Using in vitro prostate stromal cell models, we showed that conditioned media collected from PR positive stromal cells inhibited prostate cancer cell migration and invasion, but had minor suppressive impacts on cancer cell proliferation. PR suppressed the secretion of stromal derived factor-1 (SDF-1 and interlukin-6 (IL-6 by stromal cells independent to PR ligands. Blocking PR expression by siRNA or supplementation of exogenous SDF-1 or IL-6 to conditioned media from PR positive stromal cells counteracted the inhibitory effects of PR to cancer cell migration and invasion.Decreased expression of the PR in cancer associated stroma may contribute to the elevated SDF-1 and IL-6 levels in prostate tumors and enhance prostate tumor progression.

  5. Selective progesterone receptor modulators for fertility preservation in women with symptomatic uterine fibroids.

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    Ali, Mohamed; Al-Hendy, Ayman

    2017-09-01

    Uterine fibroids (UFs, AKA leiomyoma) are the most important benign neoplastic threat to women's health, with costs up to hundreds of billions of health care dollars worldwide. Uterine fibroids caused morbidities exert a tremendous health toll, impacting the quality of life of women of all ethnicities, especially women of color. Clinical presentations include heavy vaginal bleeding, pelvic pain, bulk symptoms, subfertility, and obstetric complications. Current management strategies heavily lean toward surgical procedures; nonetheless, the choice of treatment is generally subject to patient's age and her desire to preserve future fertility. Women with UF who desire to maintain future fertility potential face a dilemma because of the limited treatment choices that are currently available to help them achieve that goal. Recently, ulipristal acetate the first of the promising family of oral selective progesterone receptor modulators has been approved for UF treatment in Europe, Canada, and several other countries and is under review for possible approval in the USA. In this review article, we discuss recent advances in the management options against UF with a bend toward oral effective long-term treatment alternatives who are particularly suited for those seeking to preserve their future fertility potential. We also explore the transformative concept of primary and secondary UF prevention using these new anti-UF agents. We envision a remarkable shift in the management of UF in future years from surgical/invasive treatment to orally administrated options; clearly, this potential shift will require additional intense clinical research. © The Authors 2017. Published by Oxford University Press on behalf of Society for the Study of Reproduction.

  6. Role of progesterone receptor polymorphisms in the recurrent spontaneous abortions: Indian case.

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    Meka Aruna

    Full Text Available BACKGROUND: We attempt to ascertain if the 3 linked single nucleotide polymorphisms (SNPs of the Progesterone Receptor (PR gene (exon 1: G 1031 C; S344T, exon 4: G 1978 T; L660V and exon 5: C 2310 T; H770H and the PROGINS insertion in the intron G, between exons 7 and 8, are associated with Recurrent Spontaneous Abortion (RSA in the Indian population. METHODOLOGY/PRINCIPAL FINDINGS: A total of 143 women with RSA and 150 controls were sequenced for all the 8 exons looking for the above 3 linked SNPs of the PR gene earlier implicated in the RSA, as well as for any new SNPs that may be possibly found in the Indian population. PROGINS insertion was screened by electrophoresis. We did not find any new mutations, not observed earlier, in our population. Further, we did not find significant role of the *2 allele (representing the mutant allele at the three SNP loci or the T2 allele (PROGINS insertion in the manifestation of RSA. We also did not find an LD pattern between each of the 3 SNPs and the PROGINS insertion. CONCLUSIONS/SIGNIFICANCE: The results suggest that the PR gene mutations may not play any exclusive role in the manifestation of RSA, and instead, given significantly higher frequency of the *2 allele among the normal women, we surmise if it does not really confer a protective role among the Indian populations, albeit further studies are required in the heterogeneous populations of this region before making any conclusive statement.

  7. 5'-Heterogeneity in human progesterone receptor transcripts predicts a new amino-terminal truncated "C"-receptor and unique A-receptor messages.

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    Wei, L L; Gonzalez-Aller, C; Wood, W M; Miller, L A; Horwitz, K B

    1990-12-01

    Human progesterone receptors (PR) are thought to comprise two naturally occurring hormone-binding proteins: 94-kDa A-receptors and 120-kDa B-receptors. In this paper we present evidence for a third human PR, an N-terminally truncated, 45- to 50-kDa species, termed the C-receptor. To determine the translational origin of B- and A-receptors we mapped the multiple messages that code for human PR by Northern blot analyses, using a series of oligonucleotides and cDNA fragment probes corresponding to different regions of the PR message. In addition to the six transcripts of 2.5, 3.2, 4.5, 5.2, 6.1, and 11.4 kilobases (kb) originally described, we found that the 11.4-kb species is a complex of four bands that we have termed I-IV. Analysis of poly(A)+ RNA derived from T47Dv human breast cancer cells using a variety of 5'-specific probes has identified three separate structural classes of human PR transcripts, indicating extensive 5'-termini heterogeneity. Class A messages, the 2.5- and 5.2-kb species, lack the sequences surrounding AUGB (codon 1), which is the translation initiation site for B-receptors, but contain AUGA (codon 165), the initiation site for A-receptors, and, therefore, potentially encode only the latter. Class B messages, consisting of the 3.2-, 4.5-, and 6.1-kb species as well as bands I and II of the 11.4-kb complex contain both AUGB and AUGA and could encode both receptor forms.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Effects of orexins A and B on expression of orexin receptors and progesterone release in luteal and granulosa ovarian cells.

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    Cataldi, Natalia I; Lux-Lantos, Victoria A R; Libertun, Carlos

    2012-10-10

    Orexin-A and orexin-B are neuropeptides controlling sleep-wakefulness, feeding and neuroendocrine functions via their G protein-coupled receptors, orexin-1R and orexin-2R. They are synthesized in the lateral hypothalamus and project throughout the brain. Orexins and orexin receptors have also been described outside the brain. Previously we demonstrated the presence of both receptors in the ovary, their increased expression during proestrous afternoon and the dependence on the gonadotropins. Here we studied the effects of orexins on the mRNA expression of both receptors, by quantitative real-time PCR, on luteal cells from superovulated rat ovaries and granulosa cells from diethylstilbestrol-treated rat ovaries. Effects on progesterone secretion were also measured. In luteal cells, 1 nM of either orexin-A or orexin-B decreased progesterone secretion. Orexin-A treatment increased expression of both orexin-1R and orexin-2R mRNA. The effect on orexin-1R mRNA expression was abolished by an orexin-1R selective receptor antagonist SB-334867 and the effect on orexin-2R mRNA expression was abolished by a selective orexin-2R antagonist JNJ-10397049. Orexin-B did not modify orexin-1R mRNA expression, but increased orexin-2R mRNA expression. The effect of orexin-B on orexin-2R was abolished by a selective orexin-2R antagonist. Neither the expression of orexin receptors nor progesterone secretions by granulosa cells were affected by orexins. FSH, as positive control, increased both steroid hormones secretion, but did not induce the expression of OX receptors in granulosa cells isolated from late preantral/early antral follicles. Finally in ovaries obtained immediately after sacrifice, the expression of orexin-1R and orexin-2R was higher in superovulated rat ovaries compared to control or diethylstilbestrol treated rat ovaries. A selective presence and function of both orexinergic receptors in luteal and granulosa cells is described, suggesting that the orexinergic system may

  9. Phosphorylated and sumoylation-deficient progesterone receptors drive proliferative gene signatures during breast cancer progression

    Science.gov (United States)

    2012-01-01

    Introduction Progesterone receptors (PR) are emerging as important breast cancer drivers. Phosphorylation events common to breast cancer cells impact PR transcriptional activity, in part by direct phosphorylation. PR-B but not PR-A isoforms are phosphorylated on Ser294 by mitogen activated protein kinase (MAPK) and cyclin dependent kinase 2 (CDK2). Phospho-Ser294 PRs are resistant to ligand-dependent Lys388 SUMOylation (that is, a repressive modification). Antagonism of PR small ubiquitin-like modifier (SUMO)ylation by mitogenic protein kinases suggests a mechanism for derepression (that is, transcriptional activation) of target genes. As a broad range of PR protein expression is observed clinically, a PR gene signature would provide a valuable marker of PR contribution to early breast cancer progression. Methods Global gene expression patterns were measured in T47D and MCF-7 breast cancer cells expressing either wild-type (SUMOylation-capable) or K388R (SUMOylation-deficient) PRs and subjected to pathway analysis. Gene sets were validated by RT-qPCR. Recruitment of coregulators and histone methylation levels were determined by chromatin immunoprecipitation. Changes in cell proliferation and survival were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays and western blotting. Finally, human breast tumor cohort datasets were probed to identify PR-associated gene signatures; metagene analysis was employed to define survival rates in patients whose tumors express a PR gene signature. Results 'SUMO-sensitive' PR target genes primarily include genes required for proliferative and pro-survival signaling. DeSUMOylated K388R receptors are preferentially recruited to enhancer regions of derepressed genes (that is, MSX2, RGS2, MAP1A, and PDK4) with the steroid receptor coactivator, CREB-(cAMP-response element-binding protein)-binding protein (CBP), and mixed lineage leukemia 2 (MLL2), a histone methyltransferase mediator of nucleosome

  10. Loss of co-ordinate expression of progesterone receptors A and B is an early event in breast carcinogenesis.

    Science.gov (United States)

    Mote, P A; Bartow, S; Tran, N; Clarke, C L

    2002-03-01

    Progesterone receptor (PR) mediates the effects of progesterone in mammary tissues and plays a crucial role in normal breast development and in breast cancer. PR proteins are expressed as two isoforms, PRA and PRB, that have different capacities to activate target genes, yet it is unknown whether progesterone action in normal and malignant breast is mediated by PRA and/or PRB. This study determines the relative expression of PRA and PRB in normal breast and in benign, premalignant and malignant archival breast lesions by dual immunofluorescent histochemistry. In normal breast and in proliferative disease without atypia (PDWA) PRA and PRB were co-expressed within the same cells in comparable amounts, implicating both isoforms in progesterone action. In atypical lesions, however, there was a significant increase in predominant expression of PRA or PRB, with lesion progression from the normal state to malignancy. PR isoform predominance, especially PRA predominance, was evident in a high proportion of ductal carcinomas in situ (DCIS) and invasive breast lesions. In the normal breast and in PDWA, the relative expression of PRA and PRB in adjacent cells was homogenous. There was a significant increase in cell-to-cell heterogeneity of PR isoform expression in ADH and DCIS lesions and in the majority of breast cancers. Heterogeneous cell-to-cell expression of PR isoforms occurred prior to overall predominant expression of one isoform in premalignant breast lesions, demonstrating that loss of control of relative PRA:PRB expression is an early event in the development of breast cancer. PRA:PRB ratios within a breast lesion are likely to be important as both markers and effectors of tumor growth and development, and progressively aberrant PR isoform expression may play a role in the etiology of breast cancer.

  11. The reliability of rabbit monoclonal antibodies in the immunohistochemical assessment of estrogen receptors, progesterone receptors, and HER2 in human breast carcinomas

    OpenAIRE

    Rhodes, A.; Sarson, J.; Assam, E. E.; Dean, S. J.; Cribb, E. C.; Parker, A.

    2010-01-01

    The reliability of the rabbit monoclonal antibodies SP1, SP2, SP3, and 4B5 was immunohistochemically assessed on a range of 96 invasive breast and carcinomas and the results compared with those achieved with established antibody markers for estrogen receptors (6F11), progesterone receptors (PgR636), and HER2 (polyclonal A0485 and clone CB11), with HER2 status validated by fluorescence in situ hybridization (FISH) and silver in situ hybridization. Optimal results depended on the duration of mi...

  12. Determination of estradiol, estrone and progesterone in serum and human endometrium in correlation to the content of steroid receptors and 17β-hydroxysteroid dehydrogenase activity during menstrual cycle

    International Nuclear Information System (INIS)

    Schmidt-Gollwitzer, M.; Eiletz, J.; Pachaly, J.

    1977-01-01

    A study has been carried out to compare the influence of estradiol estrone and progesterone on the estradiol and progesterone receptor levels and 17β-hydroxysteroid dehydrogenase (17β-HSD) activity in human endometrium. The steroid hormone concentrations were measured simultaneously in both serum and endometrial tissue. The estradiol receptor levels were highest during the early proliferative phase and were inversely correlated to the endometrial tissue and serum concentrations of estradiol and progesterone. The highest progesterone binding capacity was found in endometrical cytosol during the late proliferative phase (midcycle) of the menstrual cycle. The midcycle peak of the progesterone receptor level correlated well with the first peak of the serum and tissue concentrations of estradiol. During,the luteal phase, in contrast to the proliferative phase, the progesterone receptor level decreased whereas serum progesterone concentrations were high. Estrone concentrations were higher in secretory than proliferative endometrium and were correlated to the increase of progesterone receptor content and 17β-HSD activity during early secretory phase. The 17β-HSD activity was approximately 10-fold higher during the early secretory than during the proliferative phase. The progesterone receptor level was highly correlated to the specific 17β-HSD activity of the microsomal fraction whereas a significant inverse correlation between the enzyme activity and the estradiol receptor level was observed. (orig.) [de

  13. Positron emission mammography: correlation of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 status and 18F-FDG.

    Science.gov (United States)

    Wang, Carolyn L; MacDonald, Lawrence R; Rogers, James V; Aravkin, Aleksandr; Haseley, David R; Beatty, J David

    2011-08-01

    The study objective was to assess the correlation between (18)F-FDG uptake values on positron emission mammography (PEM), expressed as maximum uptake value and lesion-to-background ratio, and receptor status (i.e., estrogen receptor [ER], progesterone receptor [PR], and human epidermal growth factor receptor 2 [HER2]), tumor histology, and tumor grade. We also evaluated for the correlation between maximum uptake value on PEM and maximum uptake value on a whole-body PET/CT. We retrospectively reviewed our database for patients with newly diagnosed breast cancer who were referred for PEM between June 2007 and September 2009. A subset of patients also underwent a whole-body PET/CT scan. The original pathology reports were reviewed to establish the histologic type, grade, and receptor status. The study involved 98 patients with 100 lesions. ER-negative tumors and PR-negative tumors had significantly higher mean lesion-to-background ratio than did their respective receptor-positive tumors (p = 0.02). Triple-negative tumors (i.e., ER-negative, PR-negative, and HER2-negative tumors) had statistically higher mean lesion-to-background ratio than did ER-positive PR-positive HER2-negative tumors (p = 0.04). Infiltrating ductal carcinomas had significantly higher PEM FDG uptake values than did infiltrating lobular carcinomas (p = 0.02-0.04). Breast tumors with higher histologic grade also had significantly higher PEM FDG uptake values than did those with lower grade (p = 0.03 and p PEM uptake values. This study shows a correlation between PEM FDG uptake values and the prognostic factors that have been shown to predict breast cancer survival.

  14. Progesterone modulation of transmembrane helix-helix interactions between the α-subunit of Na/K-ATPase and phospholipid N-methyltransferase in the oocyte plasma membrane

    Directory of Open Access Journals (Sweden)

    Askari Amir

    2010-05-01

    Full Text Available Abstract Background Progesterone binding to the surface of the amphibian oocyte initiates the meiotic divisions. Our previous studies with Rana pipiens oocytes indicate that progesterone binds to a plasma membrane site within the external loop between the M1 and M2 helices of the α-subunit of Na/K-ATPase, triggering a cascade of lipid second messengers and the release of the block at meiotic prophase. We have characterized this site, using a low affinity ouabain binding isoform of the α1-subunit. Results Preparations of isolated plasma membranes from Rana oocytes demonstrate that physiological levels of progesterone (or the non-metabolizable progestin R5020 successively activate phosphatidylethanolamine-N-methyltransferase (PE-NMT and sphingomyelin synthase within seconds. Inhibition of PE-NMT blocks the progesterone induction of meiosis in intact oocytes, whereas its initial product, phosphatidylmonomethylethanolamine (PME, can itself initiate meiosis in the presence of the inhibitor. Published X-ray crystallographic data on Na/K-ATPase, computer-generated 3D projections, heptad repeat analysis and hydrophobic cluster analysis of the transmembrane helices predict that hydrophobic residues L, V, V, I, F and Y of helix M2 of the α1-subunit interact with F, L, G, L, L and F, respectively, of helix M3 of PE-NMT. Conclusion We propose that progesterone binding to the first external loop of the α1-subunit facilitates specific helix-helix interactions between integral membrane proteins to up-regulate PE-NMT, and, that successive interactions between two or more integral plasma membrane proteins induce the signaling cascades which result in completion of the meiotic divisions.

  15. Expression of somatostatin, dopamine, progesterone and growth hormone receptor mRNA in canine cortisol-secreting adrenocortical tumours.

    Science.gov (United States)

    Kool, Miriam M J; Galac, Sara; van der Helm, Noortje; Spandauw, Catharina G; Kooistra, Hans S; Mol, Jan A

    2015-10-01

    Cortisol-secreting adrenocortical tumours (AT) in dogs are characterised by uncontrolled growth and excessive cortisol secretion. Dysregulated hormone receptor expression might be involved in tumour growth and hypersecretion of cortisol. The relative mRNA expression of growth hormone receptor, progesterone receptor, somatostatin receptors (SSTR1-3) and dopamine receptors (DRD1-2 and DRD5) was evaluated in 36 canine ATs and 15 adrenal glands obtained from healthy dogs. Compared with normal adrenal tissue, DRD2 mRNA expression was relatively lower in carcinomas, while SSTR1 mRNA expression was lower in both adenomas and carcinomas. Both of these features might contribute to loss of inhibition of tumour growth and upregulation of cortisol secretion. In canine ATs that had recurred within 30 months of surgical adrenalectomy, a marked increase in expression of DRD1 mRNA was observed. Targeting of specific hormone receptors, expressed by ATs, might be exploited for therapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Embryonic exposure to the fungicide vinclozolin causes virilization of females and alteration of progesterone receptor expression in vivo: an experimental study in mice

    Directory of Open Access Journals (Sweden)

    Baskin Laurence S

    2006-02-01

    Full Text Available Abstract Background Vinclozolin is a fungicide that has been reported to have anti-androgenic effects in rats. We have found that in utero exposure to natural or synthetic progesterones can induce hypospadias in mice, and that the synthetic progesterone medroxyprogesterone acetate (MPA feminizes male and virilizes female genital tubercles. In the current work, we selected a relatively low dose of vinclozolin to examine its in utero effects on the development of the genital tubercle, both at the morphological and molecular levels. Methods We gave pregnant dams vinclozolin by oral gavage from gestational days 13 through 17. We assessed the fetal genital tubercles from exposed fetuses at E19 to determine location of the urethral opening. After determination of gonadal sex, either genital tubercles were harvested for mRNA quantitation, or urethras were injected with a plastic resin for casting. We analyzed quantified mRNA levels between treated and untreated animals for mRNA levels of estrogen receptors α and β, progesterone receptor, and androgen receptor using nonparametric tests or ANOVA. To determine effects on urethral length (males have long urethras compared to females, we measured the lengths of the casts and performed ANOVA analysis on these data. Results Our morphological results indicated that vinclozolin has morphological effects similar to those of MPA, feminizing males (hypospadias and masculinizing females (longer urethras. Because these results reflected our MPA results, we investigated the effects of in utero vinclozolin exposure on the mRNA expression levels of androgen, estrogen α and β, and progesterone receptors. At the molecular level, vinclozolin down-regulated estrogen receptor α mRNA in females and up-regulated progesterone receptor mRNA. Vinclozolin-exposed males exhibited up-regulated estrogen receptor α and progesterone receptor mRNA, effects we have also seen with exposure to the synthetic estrogen, ethinyl

  17. Progesterone receptor isoform analysis by quantitative real-time polymerase chain reaction in formalin-fixed, paraffin-embedded canine mammary dysplasias and tumors

    DEFF Research Database (Denmark)

    Guil-Luna, S.; Stenvang, Jan; Brünner, Nils

    2014-01-01

    and its isoforms in formalin-fixed, paraffin-embedded tissue samples from canine mammary lesions (4 dysplasias, 10 benign tumors, and 46 carcinomas) using 1-step SYBR Green quantitative real-time polymerase chain reaction (RT-qPCR). Progesterone receptor was expressed in 75% of dysplasias, all benign...... in the expression of isoform A versus B. Analysis of progesterone receptor mRNA isoforms by RT-qPCR was successful in routinely formalin-fixed, paraffin-embedded tissue samples and enabled the distribution of isoforms A and B to be identified for the first time in dysplasias, benign tumors, and malignant tumors...

  18. A facile and improved synthesis of 17[alpha]-[l brace]2-(E)-[[sup 125]I]-iodovinyl[r brace]-19-nortestosterone, a no-carrier-added ligand for progesterone receptor analyses

    Energy Technology Data Exchange (ETDEWEB)

    Damodaran, K.M. (Pittsburgh Cancer Inst., PA (United States)); Epperly, M.W.; Pillai, K.M.R.; Bloomer, W.D. (Pittsburgh Univ., PA (United States). Dept. of Radiation Oncology Pittsburgh Cancer Inst., PA (United States))

    1994-01-01

    We have synthesized the no-carrier-added progesterone receptor ligand 17[alpha]-[l brace]2-(E)-[[sup 125]I]-iodovinyl[r brace]-19-nortestosterone (E-[sup 125]IVNNT) by a simple and high yielding method, and determined its uptake and specific progesterone receptor binding in vitro using T47D human breast carcinoma cells. (Author).

  19. The role of estrogen and progesterone receptors in response rate to megestrol acetate: conservative treatment of stage Ia endometrial adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Yarandi F

    2010-12-01

    Full Text Available "nBackground: Surgery is the most effective treatment of well-differentiated endometrial cancer. But using systemic progestins, have been evaluated to treat the young patients with well-differentiated endometrial cancer who wish to preserve their fertility. The aim of this study was the evaluation of megestrol acetate on endometrial adenocarcino-ma with regard to the receptors."n "nMethods: This was a quasi-experimental study. In 16 infertile patients with stage Ia well-differentiated endometrial adenocarcinoma. The treatment initiated with 160mg/d of megestrol acetate and continued with 320mg/d for non-responsive cases. All of the patients followed with FD&C and hysteroscopy. The responsive patients were referred to IVF group and they were followed for three years."n "nResults: Of nine patient in the first step of the study, 4 (25% became pregnant. Eight patients underwent Total Abdominal Hysterectomy (TAH, and one was retreated conservatively. Of seven patient of second step of the study, five are under treatment at the time of closing the paper (three cases candidate for IVF and two are under 320 mg/d megestrol acetate, one patient is a candidate for hysterectomy, and one exited of study because of male infertility. All of the patients were progesterone receptor positive, and only one was estrogen receptor negative."n "nConclusion: Conservative treatment of early stage well-differentiated endometrial adenocarcinoma with progestins may be used in highly selected young patients who have not completed their family. Close long- term follow up in this special group of patients is necessary. The evaluation of estrogen and progesterone receptors assay may be useful in predicting response to the treatment.

  20. Clinicopathologic Characteristics of Oestrogen Receptor-Positive/Progesterone Receptor-Negative/Her2-Negative Breast Cancer According to a Novel Definition of Negative Progesterone Receptor Status: A Large Population-Based Study from China.

    Directory of Open Access Journals (Sweden)

    An-qi Li

    Full Text Available A lack of progesterone receptor (PgR expression in oestrogen receptor-positive (ER+ tumours is associated with worse survival. PgR status is usually defined as positive or negative using 1% positive nuclei as a cut-off point. In this study, we aimed to assess the clinicopathologic characteristics of ER+/PgR-/HER2- tumours by comparing them with ER+/PgR+/HER2- tumours using a PgR cut-off point of 20% as a divisive criterion.We analysed 1,522 patients with primary breast cancer who had undergone surgery at the Cancer Center of Fudan University between 2012 and 2014. Age, grade, tumour size, lymph node status and lymphovascular invasion were assessed. Multinomial logistic regression, linear regression and chi-square test models were applied to assess associations between ER, PR and clinical features.ER+/PgR-/HER2- tumours showed poorer clinicopathologic characteristics relative to ER+/PgR+/HER2- tumours using a PgR threshold of 20% instead of 1%. The clinicopathologic characteristics did not differ between tumours with purely negative PgR expression and tumours with a PgR percentage ranging from 1% to 19%. The prognostic significance of PR expression appeared more pronounced in patients under a high Ki-67 status than those under a low Ki-67 status.Based on these findings, we propose the use of a novel threshold of 20% to define PgR status. Nevertheless, the impact of this new criterion on patient management and clinical treatment requires additional study.

  1. Understanding the Inguinal Sinus in Sheep (Ovis aries—Morphology, Secretion, and Expression of Progesterone, Estrogens, and Prolactin Receptors

    Directory of Open Access Journals (Sweden)

    Graça Alexandre-Pires

    2017-07-01

    Full Text Available Post-parturient behavior of mammalian females is essential for early parent–offspring contact. After delivery, lambs need to ingest colostrum for obtaining the related immunological protection, and early interactions between the mother and the lamb are crucial. Despite visual and auditory cues, olfactory cues are decisive in lamb orientation to the mammary gland. In sheep, the inguinal sinus is located bilaterally near the mammary gland as a skin pouch (IGS that presents a gland that secretes a strong-smelling wax. Sheep IGS gland functions have many aspects under evaluation. The objective of the present study was to evaluate sheep IGS gland functional aspects and mRNA transcription and the protein expression of several hormone receptors, such as progesterone receptor (PGR, estrogen receptor 1 (ESR1, and 2 (ESR2 and prolactin receptor (PRLR present. In addition, another aim was to achieve information about IGS ultrastructure and chemical compounds produced in this gland. All hormone receptors evaluated show expression in IGS during the estrous cycle (follicular/luteal phases, pregnancy, and the post-partum period. IGS secretion is rich in triterpenoids that totally differ from the surrounding skin. They might be essential substances for the development of an olfactory preference of newborns to their mothers.

  2. In vivo phosphorylation of progesterone receptors in the T47D sub co human breast cancer cell line

    Energy Technology Data Exchange (ETDEWEB)

    Sheridan, P.L.

    1989-01-01

    We have had evidence indicating that human progesterone receptors (PR) are phosphoproteins, and used metabolic labeling with ({sup 35}S)methionine and ({sup 32}P)orthophosphate to study the synthesis, structure, and phosphorylation of PR in T47D{sub co} human breast cancer cells, a cell line extremely rich for PR. Human PR exist as two independent hormone-binding proteins; B-receptors which are triplets in SDS-gels (M{sub r} 114, 117, and 120 kDa), and A-receptors that are a single band (94 kDa). The work presented here documents that human A- and B-receptors are phosphorylated on serine residues in the untransformed state, with phosphate being incorporated into all three bands of the B-proteins. However, a brief ({sup 35}S)methionine pulse shows that both A and B are synthesized as singlets of 94 and 114 kDa, respectively. The B-triplet is formed post-translationally by slow phosphorylation. B-triplet formation, or maturation, can be reversed by treatment with calf alkaline phosphatase or stabilized by the presence of phosphatase inhibitors. Additional ({sup 35}S)labeling studies in the presence of progestins demonstrate that receptors that are 15 min old are able to bind hormone and transform to the tight nuclear binding state.

  3. Regulation of gene expression by PRA-910, a novel progesterone receptor modulator, in T47D cells.

    Science.gov (United States)

    Bray, Jeffrey D; Zhang, Zhiming; Winneker, Richard C; Lyttle, C Richard

    2003-11-01

    Progestins play an important role in women's health and are used in oral contraception, hormone therapy, and treatment of reproductive disorders. The effects of progestins upon gene expression in breast epithelium are poorly understood. In an attempt to characterize the molecular mechanism of progestin action, we used a gene expression profiling approach to examine the action of a novel progestin in the T47D cell model, a human breast cancer cell line. PRA-910 is a novel, nonsteroidal progesterone receptor modulator (PRM) with species-specific activities identified in a screen for selective PRMs. To understand the mechanism of action for PRA-910 in T47D cells, we compared its gene regulation to progesterone (P4) and RU486 through Affymetrix U95A GeneChip analysis and TaqMan RT-PCR. PRA-910, P4, and RU486 regulated 50, 108, and 16 genes by threefold or greater versus vehicle, respectively, with 18 genes having similar regulation for P4 and PRA-910. These data confirm and extend previous findings for T47D cells. We also obtained time course, concentration-response, cyclohexamide sensitivity, and PR-specificity data for two progestin-regulated genes, ATP1A1 and CLDN8. Our data demonstrate that PRA-910 has a unique gene regulation profile distinct from both P4 and RU486. Further investigation of the underlying mechanism for these differences is ongoing.

  4. X-ray structures of progesterone receptor ligand binding domain in its agonist state reveal differing mechanisms for mixed profiles of 11beta-substituted steroids.

    NARCIS (Netherlands)

    Lusher, S.J.; Raaijmakers, H.C.A.; Vu-Pham, D.; Kazemier, B.; Bosch, R.; McGuire, R.; Azevedo, R.; Hamersma, H.; Dechering, K.; Oubrie, A.; Duin, M. van; Vlieg, J. de

    2012-01-01

    We present here the x-ray structures of the progesterone receptor (PR) in complex with two mixed profile PR modulators whose functional activity results from two differing molecular mechanisms. The structure of Asoprisnil bound to the agonist state of PR demonstrates the contribution of the ligand

  5. Estrogen-Receptor, Progesterone-Receptor and HER2 Status Determination in Invasive Breast Cancer. Concordance between Immuno-Histochemistry and MapQuant™ Microarray Based Assay.

    Directory of Open Access Journals (Sweden)

    D Mouttet

    Full Text Available Hormone receptor status and HER2 status are of critical interest in determining the prognosis of breast cancer patients. Their status is routinely assessed by immunohistochemistry (IHC. However, it is subject to intra-laboratory and inter-laboratory variability. The aim of our study was to compare the estrogen receptor, progesterone receptor and HER2 status as determined by the MapQuant™ test to the routine immuno-histochemical tests in early stage invasive breast cancer in a large comprehensive cancer center.We retrospectively studied 163 invasive early-stage breast carcinoma with standard IHC status. The genomic status was determined using the MapQuant™ test providing the genomic grade index.We found only 4 tumours out of 161 (2.5% with discrepant IHC and genomic results concerning ER status. The concordance rate between the two methods was 97.5% and the Cohen's Kappa coefficient was 0.89. Comparison between the MapQuant™ PR status and the PR IHC status gave more discrepancies. The concordance rate between the two methods was 91.4% and the Cohen's Kappa coefficient was 0.74. The HER2 MapQuant™ test was classified as « undetermined » in 2 out of 163 cases (1.2%. One HER2 IHC-negative tumour was found positive with a high HER2 MapQuant™ genomic score. The concordance rate between the two methods was 99.3% and the Cohen's Kappa coefficient was 0.86.Our results show that the MapQuant™ assay, based on mRNA expression assay, provides an objective and quantitative assessment of Estrogen receptor, Progesterone receptor and HER2 status in invasive breast cancer.

  6. Estrogen-Receptor, Progesterone-Receptor and HER2 Status Determination in Invasive Breast Cancer. Concordance between Immuno-Histochemistry and MapQuant™ Microarray Based Assay

    Science.gov (United States)

    Mouttet, D.; Laé, M.; Caly, M.; Gentien, D.; Carpentier, S.; Peyro-Saint-Paul, H.; Vincent-Salomon, A.; Rouzier, R.; Sigal-Zafrani, B.; Sastre-Garau, X.; Reyal, F.

    2016-01-01

    Background Hormone receptor status and HER2 status are of critical interest in determining the prognosis of breast cancer patients. Their status is routinely assessed by immunohistochemistry (IHC). However, it is subject to intra-laboratory and inter-laboratory variability. The aim of our study was to compare the estrogen receptor, progesterone receptor and HER2 status as determined by the MapQuant™ test to the routine immuno-histochemical tests in early stage invasive breast cancer in a large comprehensive cancer center. Patients and Methods We retrospectively studied 163 invasive early-stage breast carcinoma with standard IHC status. The genomic status was determined using the MapQuant™ test providing the genomic grade index. Results We found only 4 tumours out of 161 (2.5%) with discrepant IHC and genomic results concerning ER status. The concordance rate between the two methods was 97.5% and the Cohen’s Kappa coefficient was 0.89. Comparison between the MapQuant™ PR status and the PR IHC status gave more discrepancies. The concordance rate between the two methods was 91.4% and the Cohen’s Kappa coefficient was 0.74. The HER2 MapQuant™ test was classified as « undetermined » in 2 out of 163 cases (1.2%). One HER2 IHC-negative tumour was found positive with a high HER2 MapQuant™ genomic score. The concordance rate between the two methods was 99.3% and the Cohen’s Kappa coefficient was 0.86. Conclusion Our results show that the MapQuant™ assay, based on mRNA expression assay, provides an objective and quantitative assessment of Estrogen receptor, Progesterone receptor and HER2 status in invasive breast cancer. PMID:26829108

  7. Chronic exposure to bisphenol a impairs progesterone receptor-mediated signaling in the uterus during early pregnancy.

    Science.gov (United States)

    Li, Quanxi; Davila, Juanmahel; Bagchi, Milan K; Bagchi, Indrani C

    2016-01-01

    Environmental and occupational exposure to endocrine disrupting chemicals (EDCs) is a major threat to female reproductive health. Bisphenol A (BPA), an environmental toxicant that is commonly found in polycarbonate plastics and epoxy resins, has received much attention due to its estrogenic activity and high risk of chronic exposure in human. Whereas BPA has been linked to infertility and recurrent miscarriage in women, the impact of its exposure on uterine function during early pregnancy remains unclear. In a recent publication in Endocrinology , we demonstrated that prolonged exposure to an environmental relevant dose of BPA disrupts progesterone receptor-regulated uterine functions, thus affecting uterine receptivity for embryo implantation and decidua morphogenesis, two critical events for establishment and maintenance of early pregnancy. In particular we reported a marked impairment of progesterone receptor (PGR) expression and its downstream effector HAND2 in the uterine stromal cells in response to chronic BPA exposure. In an earlier study we have shown that HAND2 controls embryo implantation by repressing fibroblast growth factor (FGF) expression and the MAP kinase signaling pathway, thus inhibiting epithelial proliferation. Interestingly we observed that downregulation of PGR and HAND2 expression in uterine stroma upon BPA exposure was associated with an enhanced activation of FGFR and MAPK signaling, aberrant proliferation, and lack of uterine receptivity in the epithelium. In addition, the proliferation and differentiation of endometrial stromal cells to decidual cells, an event critical for the maintenance of early pregnancy, was severely compromised in response to BPA. This research highlight will provide an overview of our findings and discuss the potential mechanisms by which chronic BPA impairs PGR-HAND2 pathway and adversely affects implantation and the establishment of pregnancy.

  8. Characterization of Molecular Changes in Endometrium Associated With Chronic Use of Progesterone Receptor Modulators: Ulipristal Acetate Versus Mifepristone.

    Science.gov (United States)

    Kannan, Athilakshmi; Bhurke, Arpita; Sitruk-Ware, Regine; Lalitkumar, Parameswaran G; Gemzell-Danielsson, Kristina; Williams, Alistair R W; Taylor, Robert N; Bagchi, Milan K; Bagchi, Indrani C

    2018-03-01

    Ulipristal acetate (UPA) is a selective progesterone receptor modulator (PRM), which is used as an emergency contraceptive in women. Recent studies demonstrated the efficacy of an UPA contraceptive vaginal ring (UPA-CVR) as a blocker of ovulation. However, the endometrium of women exposed to UPA over a 6-month period display glandular changes, termed PRM-associated endometrial changes (PAECs). We, therefore, investigated whether UPA-induced PAECs are associated with altered expression of the transcription factor heart- and neural crest derivatives-expressed protein 2 (HAND2) whose downregulation is observed in endometrial epithelial hyperplasia and cancer. Our results showed that while exposure to mifepristone, a well-known PRM, leads to suppression of endometrial HAND2 expression, long-term exposure to UPA-CVR did not cause downregulation of this marker. Further studies, using human primary endometrial stromal cells, confirmed that whereas mifepristone-mediated suppression of HAND2 elevated the levels of its downstream target fibroblast growth factor 18, UPA did not significantly alter the expression of this growth factor. A rationale for the differential regulation of HAND2 by these PRMs was provided by our observation that mifepristone-bound progesterone receptors turn over at a faster rate than those bound to UPA. Collectively, these results support the selective effects of different PRMs and indicate that chronic exposure to UPA does not alter the HAND2 pathway whose dysregulation is linked to complex atypical endometrial hyperplasia and cancer. The results from this study involving a limited number of clinical samples should pave the way for a larger study to determine the safety of UPA for long-term use.

  9. Membrane Estrogen Receptor-α Interacts with Metabotropic Glutamate Receptor Type 1a to Mobilize Intracellular Calcium in Hypothalamic Astrocytes

    Science.gov (United States)

    Kuo, John; Hariri, Omid R.; Bondar, Galyna; Ogi, Julie; Micevych, Paul

    2009-01-01

    Estradiol, acting on a membrane-associated estrogen receptor-α (mERα), induces an increase in free cytoplasmic calcium concentration ([Ca2+]i) needed for progesterone synthesis in hypothalamic astrocytes. To determine whether rapid estradiol signaling involves an interaction of mERα with metabotropic glutamate receptor type 1a (mGluR1a), changes in [Ca2+]i were monitored with the calcium indicator, Fluo-4 AM, in primary cultures of female postpubertal hypothalamic astrocytes. 17β-Estradiol over a range of 1 nm to 100 nm induced a maximal increase in [Ca2+]i flux measured as a change in relative fluorescence [ΔF Ca2+ = 615 ± 36 to 641 ± 47 relative fluorescent units (RFU)], whereas 0.1 nm of estradiol stimulated a moderate [Ca2+]i increase (275 ± 16 RFU). The rapid estradiol-induced [Ca2+]i flux was blocked with 1 μm of the estrogen receptor antagonist ICI 182,780 (635 ± 24 vs. 102 ± 11 RFU, P estradiol-induced membrane signaling in astrocytes. PMID:18948402

  10. Prostaglandin F2 alpha metabolite and progesterone profiles in post-partum cows with retained foetal membranes.

    Science.gov (United States)

    Bekana, M; Odensvik, K; Kindahl, H

    1996-01-01

    Post-partum prostaglandin release and resumption of cyclical ovarian activities were studied in 11 Swedish dairy cows with retained foetal membranes (RFM), leaving the RFM untreated. The main PGF2 alpha metabolite, 15-ketodihydro-PGF2 alpha, was measured in blood plasma collected twice daily during the first 50-60 days after delivery. Progesterone was monitored from all morning samples to evaluate the resumption of ovarian activity. The plasma levels of 15-ketodihydro-PGF2 alpha were arbitrarily considered to be significantly elevated between 6-24 days when they exceeded the mean basal value + 2 standard deviations. Comparison between this duration in days of the post-partum PGF2 alpha release and the time required for the completion of uterine involution, placental shedding and last day of post-partum clinical signs showed no significant relations. However, prior to a final decrease below a line of significance of 233-590 pmol/l, pronounced sustained and pulsatile release of PGF2 alpha occurred in relation to the increased frequency of the bacteriological findings. These additional periods of PGF2 alpha release were described as the "total" duration of post-partum release, and were found to be positively correlated with the time required for uterine involution from the stand point of rectal palpation (p < 0.05), while a tendency towards a positive relationship existed for the last day post-partum of clinical signs (p = 0.11). Progesterone analysis revealed resumption of ovarian activity and the first ovulation occurred between 19-29 days in 70% of the cows. The levels of the PGF2 alpha metabolite were again high at the time of luteolysis, thus terminating the luteal phase in the ovulating animals. Thus, it is seen that non-removal of the RFM or the resultant intrauterine infection do not prolong the duration of the immediate post-partum release of PGF2 alpha as compared to normal animals. However, a second release is associated with the increased frequency of

  11. Immunohistochemical evaluation of estrogen and progesterone receptors in peripheral and central giant cell granuloma of the jaws

    Directory of Open Access Journals (Sweden)

    Razavi SM

    2006-07-01

    Full Text Available Background and Aim: Giant cell granuloma is a relatively common benign proliferative lesion of the oral cavity. This lesion has a marked gender predilection with more prevalence in females and tendency to rapid growth and recurrence during pregnancy. The aim of this study was the evaluation of specific receptors of sex hormones in giant cell granuloma. Materials and Methods: In this cross-sectional study, twenty five cases of formalin fixed paraffin embedded giant cell granulomas were retrieved from the oral pathology archive of dental school Isfahan University of Medical Sciences. Also twenty five normal oral mucosa biopsies resected during different surgical procedures were prepared as control group. Cases were immunohistochemically stained for estrogen and progesterone receptors using the biotin-streptavidine method. Data were analyzed by SPSS package. Results: Staining for ER/PR markers were negative for the mononuclear stromal cells and multinucleated giant cells in all cases. The epithelial cells and connective tissue stromal cells of the control group were also negative for these receptors. Conclusion: Based on the results of this study, immunostaining for ER/PR was negative in all cases. These findings suggest that in most cases development and growth of this lesion is not directly related to these hormones. However further studies with more sensitive techniques are recommended.

  12. Influence of domain interactions on conformational mobility of the progesterone receptor detected by hydrogen/deuterium exchange mass spectrometry.

    Science.gov (United States)

    Goswami, Devrishi; Callaway, Celetta; Pascal, Bruce D; Kumar, Raj; Edwards, Dean P; Griffin, Patrick R

    2014-07-08

    Structural and functional details of the N-terminal activation function 1 (AF1) of most nuclear receptors are poorly understood due to the highly dynamic intrinsically disordered nature of this domain. A hydrogen/deuterium exchange (HDX) mass-spectrometry-based investigation of TATA box-binding protein (TBP) interaction with various domains of progesterone receptor (PR) demonstrate that agonist-bound PR interaction with TBP via AF1 impacts the mobility of the C-terminal AF2. Results from HDX and other biophysical studies involving agonist- and antagonist-bound full-length PR and isolated PR domains reveal the molecular mechanism underlying synergistic transcriptional activation mediated by AF1 and AF2, dominance of PR-B isoform over PR-A, and the necessity of AF2 for full AF1-mediated transcriptional activity. These results provide a comprehensive picture elaborating the underlying mechanism of PR-TBP interactions as a model for studying nuclear receptor (NR)-transcription factor functional interactions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Abundance and Localization of Progesterone Receptor Isoforms in Endometrium in Women With and Without Endometriosis and in Peritoneal and Ovarian Endometriotic Implants.

    Science.gov (United States)

    Bedaiwy, Mohamed A; Dahoud, Wissam; Skomorovska-Prokvolit, Yelena; Yi, Lijuan; Liu, James H; Falcone, Tommaso; Hurd, William W; Mesiano, Sam

    2015-09-01

    Several studies suggest that resistance to progesterone may contribute to the pathophysiology of endometriosis. Progesterone mediates its biological activity via the 2 progesterone receptor (PR) isoforms (PR-A and PR-B). Effects of progesterone are determined by the PR-A:PR-B ratio such that a PR-B-dominant state promotes progesterone signaling, whereas a PR-A-dominant state decreases progesterone responsiveness. Our objective was to compare the abundance and cellular localization of the PR isoforms in endometrium and endometriotic lesions from women with and without peritoneal and ovarian endometriosis. This in vitro study was conducted in a tertiary care facility. Reproductive-age women with surgically diagnosed endometriosis (n = 18) and asymptomatic control individuals (n = 20) were prospectively recruited at the late proliferative and the early secretory phases. At laparoscopy, samples of eutopic endometrium, peritoneal and ovarian endometriosis, and disease-free peritoneum were obtained for subsequent immunohistochemical and immunoblot analysis of PR-B and total PR localization and PR-A and PR-B abundance, respectively. The PR-A and PR-B were detected in eutopic endometrium and in peritoneal and ovarian endometriosis but not in disease-free peritoneum from patients with and without endometriosis. In peritoneal endometriosis, PR-A was the predominant isoform detected, whereas both receptors were detected in ovarian endometriosis and eutopic endometrium. In eutopic endometrium, levels of PR-A were significantly elevated in women with endometriosis compared with women without disease, regardless of menstrual phase. The PR-A levels were significantly elevated in ovarian endometriosis compared with peritoneal endometriosis. Endometriotic lesions and eutopic endometrium from women with endometriosis are uniform in a PR-A-dominant state. The data suggest that menstrual efflux of a PR-A-dominant endometrial tissue into the peritoneal cavity may play a role in the

  14. The presence and role of progesterone receptor in the ovaries of postmenopausal women who have not applied hormone replacement therapy.

    Directory of Open Access Journals (Sweden)

    Małgorzata Piasecka

    2008-12-01

    Full Text Available At present, not much is known about progesterone receptor (PR expression and localization in postmenopausal women ovaries. In the ovaries of reproductive age women, PR is localized in internal theca and granulosa cells, corpus luteum, ovary surface epithelium (OSE and in stroma. PR expression depends on the serum concentration of progesterone, estrogen, gonadotropin and androgen. The goal of the conducted studies was to examine PR localization and expression in the ovaries of postmenopausal women who have not applied hormone replacement therapy so far. Also, the correlation was examined between PR expression and localization in the ovaries, steroid and gonadotropin hormone serum concentrations, and influence of the time from the last menstruation. The material came from 50 postmenopausal women who had their ovaries removed due to non-neoplastic diseases. The women were divided into 3 groups (A, B, C depending on the time from the last menstruation. The follitropin (FSH, luteotropin (LH, estradiol (E2, testosterone (T, androstendione (A and dehydroepiandrosterone sulphate (DHEAS concentrations in blood plasma were measured. Monoclonal mouse anti-human PR antibody was used for immunohistochemical detection (examination involved 50 postmenopausal ovaries. Between particular groups, E2 serum concentrations did not differ, but FSH, LH, T, A, DHEAS serum concentrations were significantly different. Immunohistochemical nuclear localization of PR in postmenopausal women ovaries was observed. PR expression was similar in all three groups (A, B, C. PR expression was observed in OSE nuclei and invaginations cysts deriving from the isolation of invaginated epithelium and metaplastic columnar epithelium and in stroma. In the ovaries of postmenopausal women who have not applied hormone replacement therapy so far, PR was detected in all three groups. Its expression did not depend on the time from menopause and was similar in all examined groups. FSH, LH, T, A

  15. Uterine and placental expression of TRPV6 gene is regulated via progesterone receptor- or estrogen receptor-mediated pathways during pregnancy in rodents

    Directory of Open Access Journals (Sweden)

    Choi Kyung-Chul

    2009-05-01

    Full Text Available Abstract Transient receptor potential cation channel, subfamily V, member 6 (TRPV6 is an epithelial Ca2+ channel protein expressed in calcium absorbing organs. In the present study, we investigated the expression and regulation of uterine and placental TRPV6 during gestation in rodents. Uterine TRPV6 peaked at pregnancy day (P 0.5, P5.5 and, P13.5 and was detected in uterine epithelium and glands of rats, while placental TRPV6 mRNA levels increased in mid-gestation. Uterine and placental TRPV6 mRNA levels in rats appear to cyclically change during pregnancy, suggesting that TRPV6 may participate in the implantation process. In addition, uterine TRPV6 mRNA is only expressed in placenta-unattached areas of the uterus, and uterine TRPV6 immunoreactivity was observed in luminal and glandular epithelial cells. In the placenta, TRPV6 was detected in the labyrinth and spongy zone. These results may indicate that TRPV6 has at least two functions: implantation of the embryo and maintenance of pregnancy. To investigate the pathway(s mediating TRPV6 expression in rodents, anti-steroid hormone antagonists were injected prior to maximal TRPV6 expression. In rats, TRPV6 expression was reduced by RU486 (an anti-progesterone through progesterone receptors, and ICI 182,780 (an anti-estrogen blocked TRPV6 expression via estrogen receptors in mice. The juxtaposition of uterine and placental TRPV6 expressed in these tissues supports the notion that TRPV6 participates in transferring calcium ions between the maternal and fetal compartments. Taken together, TRPV6 gene may function as a key element in controlling calcium transport in the uterus between the embryo and the placenta during pregnancy.

  16. Progesterone receptor blockade in human breast cancer cells decreases cell cycle progression through G2/M by repressing G2/M genes

    International Nuclear Information System (INIS)

    Clare, Susan E.; Gupta, Akash; Choi, MiRan; Ranjan, Manish; Lee, Oukseub; Wang, Jun; Ivancic, David Z.; Kim, J. Julie; Khan, Seema A.

    2016-01-01

    The synthesis of specific, potent progesterone antagonists adds potential agents to the breast cancer prevention and treatment armamentarium. The identification of individuals who will benefit from these agents will be a critical factor for their clinical success. We utilized telapristone acetate (TPA; CDB-4124) to understand the effects of progesterone receptor (PR) blockade on proliferation, apoptosis, promoter binding, cell cycle progression, and gene expression. We then identified a set of genes that overlap with human breast luteal-phase expressed genes and signify progesterone activity in both normal breast cells and breast cancer cell lines. TPA administration to T47D cells results in a 30 % decrease in cell number at 24 h, which is maintained over 72 h only in the presence of estradiol. Blockade of progesterone signaling by TPA for 24 h results in fewer cells in G2/M, attributable to decreased expression of genes that facilitate the G2/M transition. Gene expression data suggest that TPA affects several mechanisms that progesterone utilizes to control gene expression, including specific post-translational modifications, and nucleosomal organization and higher order chromatin structure, which regulate access of PR to its DNA binding sites. By comparing genes induced by the progestin R5020 in T47D cells with those increased in the luteal-phase normal breast, we have identified a set of genes that predict functional progesterone signaling in tissue. These data will facilitate an understanding of the ways in which drugs such as TPA may be utilized for the prevention, and possibly the therapy, of human breast cancer. The online version of this article (doi:10.1186/s12885-016-2355-5) contains supplementary material, which is available to authorized users

  17. Progesterone radioimmunoassay

    International Nuclear Information System (INIS)

    Allen, R.M.; Redshaw, M.R.

    1981-01-01

    This patent claims a radioimmunoassay for progesterone, which comprises contacting, in an acidic medium a sample of liquid with a predetermined amount of antibodies raised against a progesterone-protein complex, the protein being attached to the 11-position of progesterone by means of a bridging group and with a predetermined amount of a progesterone derivative having an iodinatable group attached to its 3-position by means of a bridging group, the iodinatable group being iodinated with one or more atom(s) of a radioisotope of iodine, separating the steroid bound in the resulting antibody-antigen complex from the free steroid and measuring the radioactivity of the free steroid component or of the antibody-antigen complex. Sufficient sensitivity has been achieved to enable a progesterone assay to be carried out directly on a sample of biological fluid, such as serum, plasma, urine or milk. (U.K.)

  18. Diffusion Profiling via a Histogram Approach Distinguishes Low-grade from High-grade Meningiomas, Can Reflect the Respective Proliferative Potential and Progesterone Receptor Status.

    Science.gov (United States)

    Gihr, Georg Alexander; Horvath-Rizea, Diana; Garnov, Nikita; Kohlhof-Meinecke, Patricia; Ganslandt, Oliver; Henkes, Hans; Meyer, Hans Jonas; Hoffmann, Karl-Titus; Surov, Alexey; Schob, Stefan

    2018-02-01

    Presurgical grading, estimation of growth kinetics, and other prognostic factors are becoming increasingly important for selecting the best therapeutic approach for meningioma patients. Diffusion-weighted imaging (DWI) provides microstructural information and reflects tumor biology. A novel DWI approach, histogram profiling of apparent diffusion coefficient (ADC) volumes, provides more distinct information than conventional DWI. Therefore, our study investigated whether ADC histogram profiling distinguishes low-grade from high-grade lesions and reflects Ki-67 expression and progesterone receptor status. Pretreatment ADC volumes of 37 meningioma patients (28 low-grade, 9 high-grade) were used for histogram profiling. WHO grade, Ki-67 expression, and progesterone receptor status were evaluated. Comparative and correlative statistics investigating the association between histogram profiling and neuropathology were performed. The entire ADC profile (p10, p25, p75, p90, mean, median) was significantly lower in high-grade versus low-grade meningiomas. The lower percentiles, mean, and modus showed significant correlations with Ki-67 expression. Skewness and entropy of the ADC volumes were significantly associated with progesterone receptor status and Ki-67 expression. ROC analysis revealed entropy to be the most accurate parameter distinguishing low-grade from high-grade meningiomas. ADC histogram profiling provides a distinct set of parameters, which help differentiate low-grade versus high-grade meningiomas. Also, histogram metrics correlate significantly with histological surrogates of the respective proliferative potential. More specifically, entropy revealed to be the most promising imaging biomarker for presurgical grading. Both, entropy and skewness were significantly associated with progesterone receptor status and Ki-67 expression and therefore should be investigated further as predictors for prognostically relevant tumor biological features. Since absolute ADC

  19. Dienogest is a selective progesterone receptor agonist in transactivation analysis with potent oral endometrial activity due to its efficient pharmacokinetic profile.

    Science.gov (United States)

    Sasagawa, Shinichi; Shimizu, Yutaka; Kami, Hideaki; Takeuchi, Takashi; Mita, Shizuka; Imada, Kazunori; Kato, Shigeaki; Mizuguchi, Kiyoshi

    2008-02-01

    Dienogest was introduced as an oral progestin. Yet its strong oral potency on endometrial activity is not clearly explained. To circumvent this situation, steroid hormone receptor profiling using transactivation assay and endometrial activity test in rabbits were carried out with determination of plasma drug concentration. Agonistic/antagonistic activity on human progesterone receptor (PR), androgen receptor (AR), glucocorticoid receptor (GR), mineralocorticoid receptor (MR), estrogen receptor alpha (ERalpha), or estrogen receptor beta (ERbeta) were determined. Dienogest activate PR (EC50=3.4 or 10.5 nmol/l) with antagonistic activity on AR (EC50=420.6 or 775.0 nmol/l) but not agonistic nor antagonistic action on GR, MR (3000 nmol/l). Dienogest activate neither ERalpha nor ERbeta (3000 nmol/l). Progesterone activated PR with antagonistic activity on AR and on MR. Dydrogesterone showed a similar profile to progesterone. Norethisterone activated PR, AR, and ERalpha. Medroxyprogesterone acetate activated PR, AR, and GR. Danazol activated PR and AR. Collectively, dienogest has a good specificity to PR compared with the other drugs. By oral treatment, dienogest showed the strongest endometrial activity (ED50=0.0042 mg/kg) in McPhail test among other progestins (ED50 values for MPA, DYG, NES were 0.074, 1.9, >0.05 mg/kg, respectively). Dienogest showed higher plasma concentrations than those of the other progestins with higher doses. The estimated plasma concentration of dienogest at ED50 (3.66 nmol/l) was close to its EC50 value to activate PR. Thus, the stronger oral activity of dienogest could be explained simply by its in vitro potency on PR and its oral pharmacokinetic profile.

  20. Effect of long-term treatment with steroid hormones or tamoxifen on the progesterone receptor and androgen receptor in the endometrium of ovariectomized cynomolgus macaques

    Directory of Open Access Journals (Sweden)

    Cline J Mark

    2003-02-01

    Full Text Available Abstract The progesterone receptor (PR and androgen receptor (AR belong to the nuclear receptor superfamily. Two isoforms of PR (A and B have been identified with different functions. The expression of AR, each isoform of PR and their involvement in long-term effects on the endometrium after hormonal replacement therapy (HRT or tamoxifen (TAM treatment is not known. The aims of this study were to determine PR(A+B, PRB and AR distribution by immunohistochemistry in the macaque (Macaca fascicularis endometrium. Ovariectomized (OVX animals were orally treated continuously for 35 months with either conjugated equine estrogens (CEE; medroxyprogesterone acetate (MPA; the combination of CEE/MPA; or TAM. Treatment with CEE/MPA tended to down-regulate PR in the superficial glands, but increased it in the stroma. TAM treatment increased both the PR and PRB levels in the stroma. Overall, less than 20% of the cells were positive for the PRB isoform and less variation was observed after steroid treatment. AR was found in the stroma, mainly distributed in the basal layer of the endometrium in the OVX and steroid treated groups, but was absent in the TAM treated group. No AR was found in the glandular epithelium. The present data show that long-term hormone treatment affects the PR level, and also the ratio between PRA and PRB in the endometrium.

  1. Tissue-specific Regulation of Porcine Prolactin Receptor Expression by Estrogen, Progesterone and Prolactin

    Science.gov (United States)

    Prolactin (PRL) acts through its receptor (PRLR) via both endocrine and local paracrine/autocrine pathways to regulate biological processes including reproduction and lactation. We analyzed the tissue and stage of gestation-specific regulation of PRL and PRLR expression in various tissues of pigs. ...

  2. Cell-specific immuno-localization of progesterone receptor alpha in the rabbit ovary during pregnancy and after parturition.

    Science.gov (United States)

    Abd-Elkareem, Mahmoud

    2017-05-01

    Progesterone receptor alpha (PRA) has a central coordinator role in the ovarian functions in mammals. The aim of this study was to investigate the immunolocalization of PRA in the rabbit ovary during pregnancy and after parturition. The rabbit ovary during pregnancy and after parturition had moderate cytoplasmic and moderate to intense nuclear PRA immunostaining in the ovarian surface epithelial cells, stromal cells and interstitial gland cells. The PRA was also present in granulosa cells and theca interna cells of the growing, small antral and mature Graafian follicles. Theca interna cells of the atretic antral follicle in addition to endothelial and fibroblast cells had PRA immunoreactivity. The PRA were also observed in the theca externa smooth muscle-like cells of the growing and antral follicles and in the telocytes. In the present study, the corpora haemorrhagica and early developing corpora lutea had, slight cytoplasmic and nuclear PRA immunostaining in the large lutein and small lutein cells. The endothelial cells of the corpora haemorrhagica and corpora lutea had an intense nuclear PRA immune signal. The corpora lutea at an advanced stage of development had moderate cytoplasmic and nuclear PRA immunostaining in the large lutein cells and intense nuclear PRA immunostaining in the small lutein cells. The regressed corpora lutea did not have PRA immunostaining in the apoptotic large lutein cells and moderate cytoplasmic and intense nuclear PRA immunostaining in the small lutein cells. Copyright © 2017. Published by Elsevier B.V.

  3. Decreased Progesterone Receptor B/A Ratio in Endometrial Cells by Tumor Necrosis Factor-Alpha and Peritoneal Fluid from Patients with Endometriosis.

    Science.gov (United States)

    Chae, Uisoo; Min, Jin Young; Kim, Sung Hoon; Ihm, Hyo Jin; Oh, Young Sang; Park, So Yun; Chae, Hee Dong; Kim, Chung Hoon; Kang, Byung Moon

    2016-11-01

    Progesterone resistance is thought to be a major factor that contributes to progression of endometriosis. However, it is not clear what causes progesterone resistance in endometriosis. This study aimed to assess whether cytokines or peritoneal fluid can affect progesterone receptor (PR) expression in endometrial cells and to verify whether PR expression is reduced in endometriosis. The PR-B/A ratio was measured via real-time polymerase chain reaction after in vitro culture, in which endometrial cells were treated with either tumor necrosis factor-alpha (TNF-α), interleukin-1 beta, or peritoneal fluid obtained from women with advanced-stage endometriosis. Immunohistochemistry was performed to compare PR-B expression between eutopic and ectopic endometrial tissues from women with and without advanced-stage endometriosis. The PR-B/A ratio was significantly decreased by treatment with either TNF-α (p=0.011) or peritoneal fluid from women with advanced-stage endometriosis (p=0.027). Immunoreactivity of PR-B expression was significantly lower during the secretory phase than during the proliferative phase in endometrial tissues from control subjects (pendometriosis compared with eutopic endometrium tissues from control subjects. Progesterone resistance in endometriosis may be caused by proinflammatory conditions in the pelvic peritoneal microenvironment.

  4. [Lack of progesterone receptor expression predicts poor prognosis in patients with operable ER-positive invasive breast cancer].

    Science.gov (United States)

    Ma, R M; Chen, C Z; Lin, C Q; Zhang, W; Guo, G L

    2016-09-23

    To investigate the impact of lack of progesterone receptor (PR) expression on the prognosis of patients with operable ER (estrogen receptor)-positive invasive breast cancer. We retrospectively analyzed the clinicopathological features, treatment and survival data of 318 women with ER+ /PR+ and ER+ /PR- invasive breast cancer. Among the 318 patients, there were 219 PR-positive and 99 PR-negative cases. The 5-year overall survival (OS) rate was 92.5%, and the 5-year disease-free survival (DFS) rate was 87.2% in the 318 ER-positive patients. Among them, the 5-year OS rates were significantly different between the PR-positive group (94.6%) and PR-negative group (87.8%, P=0.020), and the 5-year DFS rates were also significantly different from each other (89.8% and 81.6%, respectively, P=0.019). Univariate analysis showed that PR status, tumor size, T stage, axillary lymph node metastasis, and clinical stage were prognostic factors for OS (Plack of PR expression, T stage ≥2, and positive axillary lymph node metastasis were independent risk factors for poor DFS and OS in ER-positive breast cancer patients (Plack of PR expression was not significant in predicting poor DFS or OS when patients were in stage Ⅰ or with a small tumor (≤2 cm) (P>0.05 for all), and also showed that premenopausal women with PR-negative disease had poorer DFS and OS than PR-positive patients (PLack of PR expression is an independent risk factor for poor prognosis in patients with operable ER-positive invasive breast cancer, especially in patients with a large tumor (>2 cm), advanced clinical stage (Stage Ⅱ or Ⅲ) or in premenopausal status.

  5. Progesterone receptor isoforms PRA and PRB differentially contribute to breast cancer cell migration through interaction with focal adhesion kinase complexes.

    Science.gov (United States)

    Bellance, Catherine; Khan, Junaid A; Meduri, Geri; Guiochon-Mantel, Anne; Lombès, Marc; Loosfelt, Hugues

    2013-05-01

    Progesterone receptor (PR) and progestins affect mammary tumorigenesis; however, the relative contributions of PR isoforms A and B (PRA and PRB, respectively) in cancer cell migration remains elusive. By using a bi-inducible MDA-MB-231 breast cancer cell line expressing PRA and/or PRB, we analyzed the effect of conditional PR isoform expression. Surprisingly, unliganded PRB but not PRA strongly enhanced cell migration as compared with PR(-) cells. 17,21-Dimethyl-19-norpregna-4,9-dien-3,20-dione (R5020) progestin limited this effect and was counteracted by the antagonist 11β-(4-dimethyl-amino)-phenyl-17β-hydroxy-17-(1-propynyl)-estra-4,9-dien-3-one (RU486). Of importance, PRA coexpression potentiated PRB-mediated migration, whereas PRA alone was ineffective. PR isoforms differentially regulated expressions of major players of cell migration, such as urokinase plasminogen activator (uPA), its inhibitor plasminogen activator inhibitor type 1, uPA receptor (uPAR), and β1-integrin, which affect focal adhesion kinase (FAK) signaling. Moreover, unliganded PRB but not PRA enhanced FAK Tyr397 phosphorylation and colocalized with activated FAK in cell protrusions. Because PRB, as well as PRA, coimmunoprecipitated with FAK, both isoforms can interact with FAK complexes, depending on their respective nucleocytoplasmic trafficking. In addition, FAK degradation was coupled to R5020-dependent turnovers of PRA and PRB. Such an effect of PRB/PRA expression on FAK signaling might thus affect adhesion/motility, underscoring the implication of PR isoforms in breast cancer invasiveness and metastatic evolution with underlying therapeutic outcomes.

  6. Uterine oestrogen and progesterone receptor expression in experimental pyometra in the bitch.

    Science.gov (United States)

    De Bosschere, H; Ducatelle, R; Tshamala, M

    2003-01-01

    Pyometra was induced in five bitches by the intraluminal inoculation of a ligated uterine horn in metoestrus with an Escherichia coli suspension, the other horn serving as an uninoculated control. Histologically, the inoculated horns resembled those with naturally occurring pyometra, while the uninoculated horns had an inactive appearance instead of the normal metoestrus appearance. Immunohistochemically, the expression of sex hormone receptors in the inoculated horns corresponded with that in natural cases of pyometra. In the uninoculated horns, virtually no expression of sex hormone receptors was observed, in contrast to such expression in normal metoestrus. Bacteria-associated ovario-uterine interactions may have been responsible for the hyperplastic (inoculated horn) and inactive (uninoculated horn) uterine changes observed in this experiment.

  7. Regulation of the membrane structure by brassinosteroids and progesterone in winter wheat seedlings exposed to low temperature

    Czech Academy of Sciences Publication Activity Database

    Filek, M.; Rudolphi-Skórska, E.; Sieprawska, A.; Kvasnica, Miroslav; Janeczko, A.

    2017-01-01

    Roč. 128, DEC (2017), s. 37-45 ISSN 0039-128X R&D Projects: GA ČR GJ15-08202Y Institutional support: RVO:61389030 Keywords : 24-Epibrassinolide * 24-Epicastasterone * Galactolipids * Phospholipids * Progesterone * Seedlings * Winter wheat Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 2.282, year: 2016

  8. Expression and localisation of oestrogen and progesterone receptors in the bovine mammary gland during development, function and involution.

    Science.gov (United States)

    Schams, D; Kohlenberg, S; Amselgruber, W; Berisha, B; Pfaffl, M W; Sinowatz, F

    2003-05-01

    It is now well established that oestrogen and progesterone are absolutely essential for mammary gland development. Lactation can be induced in non-pregnant animals by sex steroid hormone treatment. Most of the genomic actions of oestrogens are mediated by two oestrogen receptors (ER)-alpha and ERbeta, and for gestagens in ruminants by the progesterone receptor (PR). Our aim was the evaluation of mRNA expression and protein (localisation and Western blotting) during mammogenesis, lactogenesis, galactopoiesis (early, middle and late) and involution (8, 24, 28, 96-108 h and 14-28 days after the end of milking) in the bovine mammary gland (total no. 53). During these stages, the mRNA was assessed by means of real-time RT-PCR (LightCycler). The protein for ERalpha, ERbeta and PR was localised by immunohistochemistry and Western blotting. The mRNA expression results indicated the existence of ERalpha, ERbeta and PR in bovine mammary gland. Both ERalpha and PR are expressed in fg/ micro g total RNA range. The highest mRNA expression was found for ERalpha and PR in the tIssue of non-pregnant heifers, followed by a significant decrease to a lower level at the time of lactogenesis with low concentrations remaining during lactation and the first 4 weeks of involution. In contrast, the expression of ERbeta was about 1000-fold lower (ag/ micro g total RNA) and showed no clear difference during the stages examined, with a significant increase only 2-4 weeks after the end of milking. Immunolocalisation for ERalpha revealed a strong positive staining in nuclei of lactocytes in non-pregnant heifers, became undetectable during pregnancy, lactogenesis and lactation, and was again detectable 14-28 days after the end of milking. In contrast, PR was localised in the nuclei of epithelial cells in the mammary tIssue of non-pregnant heifers, in primigravid animals, and during late lactation and involution. During lactogenesis, peak and mid lactation, fewer nuclei of epithelial cells were

  9. Oral contraceptive use and estrogen/progesterone receptor-negative breast cancer among African American women.

    Science.gov (United States)

    Rosenberg, Lynn; Boggs, Deborah A; Wise, Lauren A; Adams-Campbell, Lucile L; Palmer, Julie R

    2010-08-01

    Oral contraceptive formulations have changed over time, making it relevant to assess the effect of more recent formulations on breast cancer risk. In addition, some studies have found stronger positive associations of oral contraceptive use with estrogen receptor-negative (ER(-)) than with ER-positive (ER(+)) breast cancer. We carried out the first assessment of the effect of oral contraceptive use on the incidence of breast cancer classified by receptor status among African American women, a group disproportionately affected by ER(-) cancer. We followed 53,848 Black Women's Health Study participants from 1995 to 2007 through biennial health questionnaires, in which participants reported information about incident breast cancer, oral contraceptive use, and breast cancer risk factors. Pathology information was obtained on receptor status for 789 incident cases. Incidence rate ratios (IRR) with 95% confidence intervals (95% CI) were derived from Cox regression models with control for confounding factors. Ever use of oral contraceptives was more strongly associated with ER(-)PR(-) breast cancer (279 cases; IRR, 1.65; 95% CI, 1.19-2.30) than with ER(+)PR(+) cancer (386 cases; IRR, 1.11; 95% CI, 0.86-1.42). The risk of ER(-)PR(-) breast cancer increased with increasing duration of use among recent users. These results indicate that the oral contraceptive formulations used in recent decades increase breast cancer risk in African American women, with a greater effect for ER(-) than ER(+) cancer. Mechanisms to explain the adverse influence of oral contraceptive use on ER(-) breast cancer need to be elucidated. (c)2010 AACR.

  10. Distribution of estrogen receptor alpha and progesterone receptor, and leukocyte infiltration in the cervix of cyclic bitches and those with pyometra.

    Science.gov (United States)

    Kunkitti, Panisara; Srisuwatanasagul, Sayamon; Chatdarong, Kaywalee

    2011-04-01

    The objectives were to localize estrogen receptor alpha (ERα) and progesterone receptor (PR), and enumerate leukocyte infiltration in cervical tissue of normal bitches during various stages of the estrous cycle (n = 35), as well as in those developing open (n = 22) or closed-cervix pyometra (n = 19). Each pyometra group was subdivided into anestrus and diestrus. Cervical tissues were collected after ovariohysterectomy. Receptor expressions were determined by immunohistochemistry and leukocyte infiltration was evaluated in histological sections stained with haematoxylin-eosin. The assessment was performed in two parts of cervical sections: the uterine part in four tissue layers (surface epithelium (SE), lamina propria (LP), glandular epithelium (GE), and tunica muscularis (M)), and the vaginal part in three layers (SE, LP and M). An immunohistochemical total score consisted of the addition of both the intensity and proportional scores. The ERα and PR scores differed between groups (P pyometra bitches at anestrus and in closed-cervix pyometra bitches at diestrus. For all types of immune cells, there were no significant differences among stages of the estrous cycle in normal bitches, whereas neutrophils were lower in both sub-groups of closed-cervix versus open-cervix pyometra (P canine cervix. We inferred that cervical dilation in normal bitches and bitches with uterine pathology was likely controlled by different mechanisms. Receptor expressions were influenced by stage of the estrous cycle in normal bitches, whereas neutrophil infiltration in cervical tissue appeared to be involved in cervical dilation in bitches with pyometra, regardless of estrous stages. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. The prognostic value of age for invasive lobular breast cancer depending on estrogen receptor and progesterone receptor-defined subtypes: A NCDB analysis.

    Science.gov (United States)

    Liu, Jieqiong; Chen, Kai; Mao, Kai; Su, Fengxi; Liu, Qiang; Jacobs, Lisa K

    2016-02-02

    We aimed to assess the effect of age on survival according to estrogen receptor (ER) and progesterone receptor (PR)-defined lobular breast cancer subtype in a wide age range. 43,230 invasive lobular breast cancer women without comorbidities diagnosed between 2004 and 2011 in the National Cancer Database (NCDB) were analyzed. The effects of age on overall survival (OS) among different age groups were evaluated by log-rank test and Cox proportional model. Multivariate analysis showed that patients diagnosed at both young ( 0.1); and in ER-PR+ subgroup, the HRs were similar in patients younger than 70 (P > 0.1); thus, the plots of HRs in these three subtypes remained steady until the age of 60 or 70. Our findings identified that the effect of age on OS in lobular breast cancer varied with ER/PR-defined subtypes. Personalized treatment strategies should be developed to improve outcomes of breast cancer patients with different ages and ER/PR statuses.

  12. The progesterone receptor antagonist, onapristone has differential effects on the timing and control of the luteolytic mechanism depending on timing of administration in sheep.

    Science.gov (United States)

    Mann, G E; Wathes, D C; Robinson, R S

    2013-08-25

    Cyclic ewes were treated with control vehicle or progesterone receptor antagonist (onapristone; 100mg i.m. twice daily) during either early (day 3-5) or late (day 12-14) luteal phase and plasma samples collected for hormone analysis and to determine endogenous and oxytocin induced PGF2α release. On day 14 and 17, ewes were euthanised and reproductive tracts collected for ovarian morphology and endometrium for oxytoxin and steroid hormone receptor analysis. Early treatment increased LH, but not progesterone or oestradiol, while late treatment elevated all three hormones. Early treatment delayed the up-regulation of endometrial oxytocin receptors and responsiveness to oxytocin challenge, delaying luteolysis. Late treatment advanced development of oxytocin receptors and responsiveness to oxytocin though not timing of luteolysis. Patterns of hormone receptor mRNA were differentially disrupted by treatments. Results provide mechanistic insight into hormonal control of the oestrous cycle and identify the ability of the luteolytic mechanism to dissociate from functional luteolysis. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  13. Class I Cytokine Receptors: Structure and function in the Membrane

    DEFF Research Database (Denmark)

    Bugge, Katrine Østergaard

    Class I cytokine receptors are involved in important biological functions of both physiological and pathological nature in mammals. However, the molecular details of the cross-membrane signal transduction through these receptors remain obscure. One of the major reasons for this is the lack...... ample material of high quality for structural studies with NMR spectroscopy of several class I cytokine receptor TMDs. Furthermore, the structure of a class I cytokine receptor TMD in DHPC micelles was solved with solution-state NMR spectroscopy. Additionally, since structural studies of intact proteins...... receptor. This integrative structure opens up for interpreting these receptors in their intact form and offers unique insights on the topology of single-pass transmembrane receptors with intrinsically disordered domains. Dimerization of the TMDs of class I cytokine receptors has been shown to be important...

  14. Membrane Trafficking of Death Receptors: Implications on Signalling

    Directory of Open Access Journals (Sweden)

    Wulf Schneider-Brachert

    2013-07-01

    Full Text Available Death receptors were initially recognised as potent inducers of apoptotic cell death and soon ambitious attempts were made to exploit selective ignition of controlled cellular suicide as therapeutic strategy in malignant diseases. However, the complexity of death receptor signalling has increased substantially during recent years. Beyond activation of the apoptotic cascade, involvement in a variety of cellular processes including inflammation, proliferation and immune response was recognised. Mechanistically, these findings raised the question how multipurpose receptors can ensure selective activation of a particular pathway. A growing body of evidence points to an elegant spatiotemporal regulation of composition and assembly of the receptor-associated signalling complex. Upon ligand binding, receptor recruitment in specialized membrane compartments, formation of receptor-ligand clusters and internalisation processes constitute key regulatory elements. In this review, we will summarise the current concepts of death receptor trafficking and its implications on receptor-associated signalling events.

  15. Affinity of estrogens for human progesterone receptor A and B monomers and risk of breast cancer: a comparative molecular modeling study

    Directory of Open Access Journals (Sweden)

    Tarique N Hasan

    2011-03-01

    Full Text Available Tarique N Hasan1,4, Leena Grace B2, Tariq A Masoodi3,5, Gowhar Shafi4 , Ali A. Alshatwi4, P Sivashanmugham31Department of Biotechnology, Bharathiar University, Coimbator, TN, India; 2Department of Biotechnology, V. M. K. V. College of Engineering, Salem, TN, India; 3Department of Bioinformatics, Jamal Mohammed College, Bharathidasan University, Tiruchirappalli, India; 4Molecular Cancer Biology Laboratory, Department of Food Science and Nutrition, College of Food and Agricultural Sciences; 5Department of Community Health Sciences, College of Applied Medical Sciences, King Saud University, Saudi ArabiaBackground: The human progesterone receptor (hPR belongs to the steroid receptor family. It may be found as monomers (A and B and or as a dimer (AB. hPR is regarded as the prognostic biomarker for breast cancer. In a cellular dimer system, AB is the dominant species in most cases. However, when a cell coexpresses all three isoforms of hPR, the complexity of the action of this receptor increases. For example, hPR A suppresses the activity of hPR B, and the ratio of hPR A to hPR B may determine the physiology of a breast tumor. Also, persistent exposure of hPRs to nonendogenous ligands is a common risk factor for breast cancer. Hence we aimed to study progesterone and some nonendogenous ligand interactions with hPRs and their molecular docking.Methods and results: A pool of steroid derivatives, namely, progesterone, cholesterol, testosterone, testolectone, estradiol, estrone, norethindrone, exemestane, and norgestrel, was used for this in silico study. Dockings were performed on AutoDock 4.2. We found that estrogens, including estradiol and estrone, had a higher affinity for hPR A and B monomers in comparison with the dimer, hPR AB, and that of the endogenous progesterone ligand. hPR A had a higher affinity to all the docked ligands than hPR B.Conclusion: This study suggests that the exposure of estrogens to hPR A as well as hPR B, and more

  16. Efficacy of endocrine therapy in relation to progesterone receptor and Ki67 expression in advanced breast cancer.

    Science.gov (United States)

    Rocca, Andrea; Farolfi, Alberto; Maltoni, Roberta; Carretta, Elisa; Melegari, Elisabetta; Ferrario, Cristiano; Cecconetto, Lorenzo; Sarti, Samanta; Schirone, Alessio; Fedeli, Anna; Andreis, Daniele; Pietri, Elisabetta; Ibrahim, Toni; Montalto, Erika; Amadori, Dino

    2015-07-01

    We assessed whether progesterone receptor (PgR) and Ki67 in primary tumors and/or matched metastases are predictors of clinical benefit from first-line endocrine therapy (ET) in advanced breast cancer. We evaluated patients treated at our institute with first-line ET (2002-2011), excluding those receiving concomitant chemotherapy or trastuzumab or pretreated with >2 lines of chemotherapy. A cut-off of 20 % immunostained cells was used for PgR and Ki67. The main endpoint was time-to-progression (TTP). Groups were compared by the log-rank test and Cox multivariate analysis. In the 135 assessable patients (93 % were receiving an aromatase inhibitor; biomarker assessment had been performed on primary tumors in 77 cases, on metastases in 23 and on both in 35), median TTP was 16 months (median follow-up 43 months). The overall discordance rate between primary tumors and metastases was 23 % for Ki67 and 31 % for PgR. A longer median TTP (24 vs. 12 months, P = 0.012) was seen for PgR >20 % in metastases. Ki67 showed a trend for TTP prediction in the entire case series (P = 0.062). Patients with high Ki67 and low PgR in metastases had a median TTP of only 5 months. High Ki67 in primary tumors (P = 0.026) or metastases (P = 0.01) predicted disease progression at the first evaluation. PgR in metastases remained a significant independent predictor of TTP at multivariate analysis (HR 2.45). In an ER-high population, PgR >20 % in metastases identified patients with a long TTP on endocrine treatment, while Ki67 >20 % was associated with an increased risk of non-response.

  17. Estradiol upregulates progesterone receptor and orphanin FQ colocalization in arcuate nucleus neurons and opioid receptor-like receptor-1 expression in proopiomelanocortin neurons that project to the medial preoptic nucleus in the female rat

    Science.gov (United States)

    Sanathara, Nayna M.; Moreas, Justine; Mahavongtrakul, Matthew; Sinchak, Kevin

    2014-01-01

    Background Ovarian steroids regulate sexual receptivity in the female rat by acting on neurons that converge on proopiomelanocortin (POMC) neurons in the arcuate nucleus of the hypothalamus (ARH) that project to the medial preoptic nucleus (MPN). Estradiol rapidly activates these neurons to release β-endorphin that activates MPN μ-opioid receptors (MOP) to inhibit lordosis. Lordosis is facilitated by the subsequent action of progesterone that deactivates the estradiol-induced MPN MOP activation. Orphanin FQ (OFQ/N; aka nociceptin) infusions into the ARH, like progesterone, deactivate MPN MOP and facilitate lordosis in estradiol-primed rats. OFQ/N reduces the activity of ARH β-endorphin neurons through post- and presynaptic mechanisms via its cognate receptor, ORL-1. Methods We tested the hypotheses that progesterone receptors (PR) are expressed in ARH OFQ/N neurons by immunohistochemistry and ORL-1 is expressed in POMC neurons that project to the MPN by combining Fluoro-Gold injection into the MPN and double-label fluorescent in situ hybridization (FISH). We also hypothesized that estradiol increases coexpression of PR-OFQ/N and ORL-1-POMC in ARH neurons of ovariectomized rats. Results The number of PR and OFQ/N immunopositive ARH neurons was increased as was their colocalization by estradiol treatment. FISH for ORL-1 and POMC mRNA revealed a subpopulation of ARH neurons that was triple-labeled indicating these neurons project to the MPN and coexpress ORL-1 and POMC mRNA. Estradiol was shown to upregulate ORL-1 and POMC expression in MPN-projecting ARH neurons. Conclusion Estradiol upregulates the ARH OFQ/N-ORL-1 system projecting to the MPN that regulates lordosis. PMID:24821192

  18. Tissue-specific regulation of porcine prolactin receptor expression by estrogen, progesterone, and prolactin.

    Science.gov (United States)

    Trott, Josephine F; Horigan, Katherine C; Gloviczki, Julia M; Costa, Kristen M; Freking, Bradley A; Farmer, Chantal; Hayashi, Kanako; Spencer, Thomas; Morabito, Joseph E; Hovey, Russell C

    2009-07-01

    Prolactin (PRL) acts through its receptor (PRLR) via both endocrine and local paracrine/autocrine pathways to regulate biological processes including reproduction and lactation. We analyzed the tissue- and stage of gestation-specific regulation of PRL and PRLR expression in various tissues of pigs. Abundance of pPRLR-long form (LF) mRNA increased in the mammary gland and endometrium during gestation while in other tissues it remained constant. There was a parallel increase in the abundance of the pPRLR-LF protein in the mammary gland and endometrium during gestation. We determined the hormonal regulation of pPRLR-LF mRNA expression in various tissues from ovariectomized, hypoprolactinemic gilts given combinations of the replacement hormones estrogen (E(2)), progestin (P), and/or haloperidol-induced PRL. Abundance of pPRLR-LF mRNA in kidney and liver was unaffected by hormone treatments. Expression of uterine pPRLR-LF mRNA was induced by E(2) whereas the effect of E(2) was abolished by co-administering P. The expression of pPRLR-LF mRNA in the mammary gland stroma was induced by PRL, whereas E(2) induced its expression in the epithelium. In contrast to these changes in pPRLR expression, pPRL expression was relatively constant and low during gestation in all tissues except the pituitary. Taken together, these data reveal that specific combinations of E(2), P, and PRL differentially regulate pPRLR-LF expression in the endometrium and mammary glands, and that the action of PRL on its target tissues is dependent upon pPRLR-LF abundance more so than the local PRL expression.

  19. The ERα coactivator, HER4/4ICD, regulates progesterone receptor expression in normal and malignant breast epithelium

    Directory of Open Access Journals (Sweden)

    Howard Beatrice A

    2010-06-01

    Full Text Available Abstract The HER4 intracellular domain (4ICD is a potent estrogen receptor (ERα coactivator with activities in breast cancer and the developing mammary gland that appear to overlap with progesterone receptor (PgR. In fact, 4ICD has recently emerged as an important regulator and predictor of tamoxifen response, a role previously thought to be fulfilled by PgR. Here we investigated the possibility that the 4ICD coactivator regulates PgR expression thereby providing a mechanistic explanation for their partially overlapping activities in breast cancer. We show that 4ICD is both sufficient and necessary to potentiate estrogen stimulation of gene expression. Suppression of HER4/4ICD expression in the MCF-7 breast tumor cell line completely eliminated estrogen stimulated expression of PgR. In addition, the HER4/4ICD negative MCF-7 variant, TamR, failed to express PgR in response to estrogen. Reintroduction of wild-type HER4 but not the γ-secretase processing mutant HER4V673I into the TamR cell line restored PgR expression indicating that 4ICD is an essential PgR coactivator in breast tumor cells. These results were substantiated in vivo using two different physiologically relevant experimental systems. In the mouse mammary gland estrogen regulates expression of PgR-A whereas expression of PgR-B is estrogen independent. Consistent with a role for 4ICD in estrogen regulated PgR expression in vivo, PgR-A, but not PgR-B, expression was abolished in HER4-null mouse mammary glands during pregnancy. Coexpression of PgR and 4ICD is also commonly observed in ERα positive breast carcinomas. Using quantitative AQUA IHC technology we found that 4ICD potentiated PgR expression in primary breast tumors and the highest levels of PgR expression required coexpression of ERα and the 4ICD coactivator. In summary, our results provide compelling evidence that 4ICD is a physiologically important ERα coactivator and 4ICD cooperates with ERα to potentiate PgR expression

  20. Antiprogestin mifepristone inhibits the growth of cancer cells of reproductive and non-reproductive origin regardless of progesterone receptor expression

    Directory of Open Access Journals (Sweden)

    Ortbahn Casey T

    2011-05-01

    Full Text Available Abstract Background Mifepristone (MF has been largely used in reproductive medicine due to its capacity to modulate the progesterone receptor (PR. The study of MF has been expanded to the field of oncology; yet it remains unclear whether the expression of PR is required for MF to act as an anti-cancer agent. Our laboratory has shown that MF is a potent inhibitor of ovarian cancer cell growth. In this study we questioned whether the growth inhibitory properties of MF observed in ovarian cancer cells would translate to other cancers of reproductive and non-reproductive origin and, importantly, whether its efficacy is related to the expression of cognate PR. Methods Dose-response experiments were conducted with cancer cell lines of the nervous system, breast, prostate, ovary, and bone. Cultures were exposed to vehicle or increasing concentrations of MF for 72 h and analysed for cell number and cell cycle traverse, and hypodiploid DNA content characteristic of apoptotic cell death. For all cell lines, expression of steroid hormone receptors upon treatment with vehicle or cytostatic doses of MF for 24 h was studied by Western blot, whereas the activity of the G1/S regulatory protein Cdk2 in both treatment groups was monitored in vitro by the capacity of Cdk2 to phosphorylate histone H1. Results MF growth inhibited all cancer cell lines regardless of tissue of origin and hormone responsiveness, and reduced the activity of Cdk2. Cancer cells in which MF induced G1 growth arrest were less susceptible to lethality in the presence of high concentrations of MF, when compared to cancer cells that did not accumulate in G1. While all cancer cell lines were growth inhibited by MF, only the breast cancer MCF-7 cells expressed cognate PR. Conclusions Antiprogestin MF inhibits the growth of different cancer cell lines with a cytostatic effect at lower concentrations in association with a decline in the activity of the cell cycle regulatory protein Cdk2, and

  1. Alterations in three biomarkers (estrogen receptor, progesterone receptor and human epidermal growth factor 2) and the Ki67 index between primary and metastatic breast cancer lesions.

    Science.gov (United States)

    Fujii, Kimihito; Watanabe, Rie; Ando, Takahito; Kousaka, Junko; Mouri, Yukako; Yoshida, Miwa; Imai, Tsuneo; Nakano, Shogo; Fukutomi, Takashi

    2017-12-01

    In recurrent breast cancer, the tumor phenotype, as assessed by estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor 2 (HER2) status, occasionally changes. This change, in addition to the Ki67 index were evaluated at sites of recurrence and the correlation between changes in tumor phenotype and survival were assessed in breast cancer patients. Comparisons in pathological parameters between primary and metastatic lesions were drawn between ER, PR, HER2, and the Ki67 index in 70 patients with recurrent breast cancer. The association between changes in tumor phenotype and patient survival was assessed. The hormone receptor status changed from positive, in the primary lesions, to negative, in the metastatic lesions in 19.8% (ER) and 39.5% (PR) of patients, respectively. Conversion from negative to positive status was confirmed in 27.2% (ER) and 31.2% (PR) of patients, respectively. A change in HER2 status from negative (primary lesion) to positive (metastatic lesion) occurred in seven patients (10%). The mean Ki67 index of primary lesions with positive hormone receptor status was significantly lower than at sites of recurrence with any hormone receptor status, from 10.9±9.8 standard deviation (SD) to 22.9±18.6 (P=0.031) and 12.2±10.5 SD to 27.4±20.9 (P=0.023), for ER and PR, respectively. The mean overall survival of patients with ER status conversion from positive to negative was 7.4±1.2 standard error (SE) years, and 14.8±1.4 SE years for patients who retained positive ER status (P=0.005, log-rank), with a hazard ratio of 3.44 (95% confidence interval, 1.36-8.33). This difference in survival based upon change in ER status was similarly observed in patients with PR status conversion in the same direction. Thus, ER and PR status conversion at the time of recurrence strongly impact survival, particularly if the change is from positive (primary lesion) to negative (metastatic lesion). Monitoring the biological behavior of breast

  2. Progesterone receptor (PR) polyproline domain (PPD) mediates inhibition of epidermal growth factor receptor (EGFR) signaling in non-small cell lung cancer cells.

    Science.gov (United States)

    Kawprasertsri, Sornsawan; Pietras, Richard J; Marquez-Garban, Diana C; Boonyaratanakornkit, Viroj

    2016-05-01

    Recent evidence has suggested a possible role for progesterone receptor (PR) in the progression of non-small cell lung cancer (NSCLC). However, little is known concerning roles of PR in NSCLC. PR contains a polyproline domain (PPD), which directly binds to the SH3 domain of signaling molecules. Because PPD-SH3 interactions are essential for EGFR signaling, we hypothesized that the presence of PR-PPD interfered with EGFR-mediated signaling and cell proliferation. We examined the role of PR-PPD in cell proliferation and signaling by stably expressing PR-B, or PR-B with disrupting mutations in the PPD (PR-BΔSH3), from a tetracycline-regulated promoter in A549 NSCLC cells. PR-B dose-dependently inhibited cell growth in the absence of ligand, and progestin (R5020) treatment further suppressed the growth. Treatment with RU486 abolished PR-B- and R5020-mediated inhibition of cell proliferation. Expression of PR-BΔSH3 and treatment with R5020 or RU486 had no effect on cell proliferation. Furthermore, PR-B expression but not PR-BΔSH3 expression reduced EGF-induced A549 proliferation and activation of ERK1/2, in the absence of ligand. Taken together, our data demonstrated the significance of PR extranuclear signaling through PPD interactions in EGFR-mediated proliferation and signaling in NSCLC. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. The association among cytochrome P450 3A, progesterone receptor polymorphisms, plasma 17-alpha hydroxyprogesterone caproate concentrations, and spontaneous preterm birth.

    Science.gov (United States)

    Bustos, Martha L; Caritis, Steve N; Jablonski, Kathleen A; Reddy, Uma M; Sorokin, Yoram; Manuck, Tracy; Varner, Michael W; Wapner, Ronald J; Iams, Jay D; Carpenter, Marshall W; Peaceman, Alan M; Mercer, Brian M; Sciscione, Anthony; Rouse, Dwight J; Ramin, Susan M

    2017-09-01

    Infants born preterm birth are the leading cause of mortality in children preterm birth by 33% in women with history of spontaneous preterm birth. We demonstrated previously that plasma concentrations of 17-alpha hydroxyprogesterone caproate vary widely among pregnant women and that women with 17-alpha hydroxyprogesterone caproate plasma concentrations in the lowest quartile had spontaneous preterm birth rates of 40% vs rates of 25% in those women with higher concentrations. Thus, plasma concentrations are an important factor in determining drug efficacy but the reason 17-alpha hydroxyprogesterone caproate plasma concentrations vary so much is unclear. Predominantly, 17-alpha hydroxyprogesterone caproate is metabolized by CYP3A4 and CYP3A5 enzymes. We sought to: (1) determine the relation between 17-alpha hydroxyprogesterone caproate plasma concentrations and single nucleotide polymorphisms in CYP3A4 and CYP3A5; (2) test the association between progesterone receptor single nucleotide polymorphisms and spontaneous preterm birth; and (3) test whether the association between plasma concentrations of 17-alpha hydroxyprogesterone caproate and spontaneous preterm birth varied by progesterone receptor single nucleotide polymorphisms. In this secondary analysis, we evaluated genetic polymorphism in 268 pregnant women treated with 17-alpha hydroxyprogesterone caproate, who participated in a placebo-controlled trial to evaluate the benefit of omega-3 supplementation in women with history of spontaneous preterm birth. Trough plasma concentrations of 17-alpha hydroxyprogesterone caproate were measured between 25-28 weeks of gestation after a minimum of 5 injections of 17-alpha hydroxyprogesterone caproate. We extracted DNA from maternal blood samples and genotyped the samples using TaqMan (Applied Biosystems, Foster City, CA) single nucleotide polymorphism genotyping assays for the following single nucleotide polymorphisms: CYP3A4*1B, CYP3A4*1G, CYP3A4*22, and CYP3A5*3; and rs

  4. Affinity Labeling of Membrane Receptors Using Tissue-Penetrating Radiations

    Directory of Open Access Journals (Sweden)

    Franklin C. Wong

    2013-01-01

    Full Text Available Photoaffinity labeling, a useful in vivo biochemical tool, is limited when applied in vivo because of the poor tissue penetration by ultraviolet (UV photons. This study investigates affinity labeling using tissue-penetrating radiation to overcome the tissue attenuation and irreversibly label membrane receptor proteins. Using X-ray (115 kVp at low doses (<50 cGy or Rad, specific and irreversible binding was found on striatal dopamine transporters with 3 photoaffinity ligands for dopamine transporters, to different extents. Upon X-ray exposure (115 kVp, RTI-38 and RTI-78 ligands showed irreversible and specific binding to the dopamine transporter similar to those seen with UV exposure under other conditions. Similarly, gamma rays at higher energy (662 keV also affect irreversible binding of photoreactive ligands to peripheral benzodiazepine receptors (by PK14105 and to the dopamine (D2 membrane receptors (by azidoclebopride, respectively. This study reports that X-ray and gamma rays induced affinity labeling of membrane receptors in a manner similar to UV with photoreactive ligands of the dopamine transporter, D2 dopamine receptor (D2R, and peripheral benzodiazepine receptor (PBDZR. It may provide specific noninvasive irreversible block or stimulation of a receptor using tissue-penetrating radiation targeting selected anatomic sites.

  5. α-Estrogen and Progesterone Receptors Modulate Kisspeptin Effects on Prolactin: Role in Estradiol-Induced Prolactin Surge in Female Rats.

    Science.gov (United States)

    Aquino, Nayara S S; Araujo-Lopes, Roberta; Henriques, Patricia C; Lopes, Felipe E F; Gusmao, Daniela O; Coimbra, Candido C; Franci, Celso R; Reis, Adelina M; Szawka, Raphael E

    2017-06-01

    Kisspeptin (Kp) regulates prolactin (PRL) in an estradiol-dependent manner. We investigated the interaction between ovarian steroid receptors and Kp in the control of PRL secretion. Intracerebroventricular injections of Kp-10 or Kp-234 were performed in ovariectomized (OVX) rats under different hormonal treatments. Kp-10 increased PRL release and decreased 3,4-dihydroxyphenylacetic acid levels in the median eminence (ME) of OVX rats treated with estradiol (OVX+E), which was prevented by tamoxifen. Whereas these effects of Kp-10 were absent in OVX rats, they were replicated in OVX rats treated with selective agonist of estrogen receptor (ER)α, propylpyrazole triol, but not of ERβ, diarylpropionitrile. Furthermore, the Kp-10-induced increase in PRL was two times higher in OVX+E rats also treated with progesterone (OVX+EP), which was associated with a reduced expression of both tyrosine hydroxylase (TH) and Ser40-phosphorylated TH in the ME. Kp-10 also reduced dopamine levels in the ME of OVX+EP rats, an effect blocked by the progesterone receptor (PR) antagonist RU486. We also determined the effect of Kp antagonism with Kp-234 on the estradiol-induced surges of PRL and luteinizing hormone (LH), using tail-tip blood sampling combined with ultrasensitive enzyme-linked immunosorbent assay. Kp-234 impaired the early phase of the PRL surge and prevented the LH surge in OVX+E rats. Thus, we provide evidence that Kp stimulation of PRL release requires ERα and is potentiated by progesterone via PR activation. Moreover, alongside its essential role in the LH surge, Kp seems to play a role in the peak phase of the estradiol-induced PRL surge. Copyright © 2017 Endocrine Society.

  6. High RAD51 mRNA expression characterize estrogen receptor-positive/progesteron receptor-negative breast cancer and is associated with patient's outcome.

    Science.gov (United States)

    Barbano, Raffaela; Copetti, Massimiliano; Perrone, Giuseppe; Pazienza, Valerio; Muscarella, Lucia Anna; Balsamo, Teresa; Storlazzi, Clelia Tiziana; Ripoli, Maria; Rinaldi, Monica; Valori, Vanna Maria; Latiano, Tiziana Pia; Maiello, Evaristo; Stanziale, Pietro; Carella, Massimo; Mangia, Alessandra; Pellegrini, Fabio; Bisceglia, Michele; Muda, Andrea Onetti; Altomare, Vittorio; Murgo, Roberto; Fazio, Vito Michele; Parrella, Paola

    2011-08-01

    Mutations in DNA double-strand breaks (DSB) repair genes are involved in the pathogenesis of hereditary mammary tumors, it is, however, still unclear whether defects in this pathway may play a role in sporadic breast cancer. In this study, we initially determined mRNA expression of 15 DSB related genes by reverse transcription quantitative polymerase chain reaction in paired normal tissue and cancer specimen from 20 breast cancer cases to classify them into homogeneous clusters. G22P1/ku70, ATR and RAD51 genes were differentially expressed in the three branches recognized by clustering analysis. In particular, a breast cancer subgroup characterized by high RAD51 mRNA levels and estrogen receptor (ER)-positive/progesteron receptor (PR)-negative phenotype was identified. This result was confirmed by the analysis of G22P1/ku70, ATR and RAD51 mRNA levels on paired normal and tumor specimens from an extended breast cancer cohort (n = 75). RAD51 mRNA levels were inversely associated with PR status (p = 0.02) and the highest levels were, indeed, detected in ER-positive/PR-negative tumors (p = 0.03). RAD51 immunostaining of a tissue microarray confirmed the inverse relationship between high RAD51 expression and negative PR status (p = 0.002), as well as, the association with ER-positive/PR-negative phenotype (p = 0.003). Interestingly, the analysis of microarray expression data from 295 breast cancers indicate that RAD51 increased mRNA expression is associated with higher risk of tumor relapse, distant metastases and worst overall survival (p = 0.015, p = 0.009 and p = 0.013 respectively). Our results suggest that RAD51 expression determination could contribute to a better molecular classification of mammary tumors and may represent a novel tool for evaluating postoperative adjuvant therapy for breast cancer patients. Copyright © 2010 UICC.

  7. Reliable PCR quantitation of estrogen, progesterone and ERBB2 receptor mRNA from formalin-fixed, paraffin-embedded tissue is independent of prior macro-dissection

    DEFF Research Database (Denmark)

    Tramm, Trine; Hennig, Guido; Kyndi, Marianne

    2013-01-01

    Gene expression analysis on messenger RNA (mRNA) purified from formalin-fixed, paraffin-embedded tissue is increasingly used for research purposes. Tissue heterogeneity may question specificity and interpretation of results from mRNA isolated from a whole slide section, and thresholds for minimal...... tumor content in the paraffin block or macrodissection are used to avoid contamination from non-neoplastic tissue. The aim was to test if mRNA from tissue surrounding breast cancer affected quantification of estrogen receptor α (ESR1), progesterone receptor (PGR) and human epidermal growth factor...... receptor 2 (ERBB2), by comparing gene expression from whole slide and tumor-enriched sections, and correlating gene expression from whole slide sections with corresponding immunohistochemistry. Gene expression, based on mRNA extracted from a training set (36 paraffin blocks) and two validation sets (133...

  8. Melatonin membrane receptors in peripheral tissues: Distribution and functions

    Science.gov (United States)

    Slominski, Radomir M.; Reiter, Russel J.; Schlabritz-Loutsevitch, Natalia; Ostrom, Rennolds S.; Slominski, Andrzej T.

    2012-01-01

    Many of melatonin’s actions are mediated through interaction with the G-protein coupled membrane bound melatonin receptors type 1 and type 2 (MT1 and MT2, respectively) or, indirectly with nuclear orphan receptors from the RORα/RZR family. Melatonin also binds to the quinone reductase II enzyme, previously defined the MT3 receptor. Melatonin receptors are widely distributed in the body; herein we summarize their expression and actions in non-neural tissues. Several controversies still exist regarding, for example, whether melatonin binds the RORα/RZR family. Studies of the peripheral distribution of melatonin receptors are important since they are attractive targets for immunomodulation, regulation of endocrine, reproductive and cardiovascular functions, modulation of skin pigmentation, hair growth, cancerogenesis, and aging. Melatonin receptor agonists and antagonists have an exciting future since they could define multiple mechanisms by which melatonin modulates the complexity of such a wide variety of physiological and pathological processes. PMID:22245784

  9. New iodinated progestins as potential ligands for progesterone receptor imaging in breast cancer. part 2: in vivo pharmacological characterization

    International Nuclear Information System (INIS)

    Rijks, Leonie J.M.; Bos, Jan C. van den; Doremalen, Peter A.P.M. van; Boer, Gerard J.; Bruin, Kora de; Janssen, Anton G.M.; Royen, Eric A. van

    1998-01-01

    On the basis of the observed high selective binding to both the human and rat progesterone receptor (PR) in vitro, three 17α-iodovinyl-substituted nortestosterone derivatives, i.e., the Z-isomer of 17α-iodovinyl-19-nortestosterone (Z-IVNT; Z-IPG1) and both the stereoisomers of 17α-iodovinyl-18-methyl-11-methylene-19-nortestosterone (E-and Z-IPG2), were selected for radio-iodination and subsequently evaluated as potential radioligands for PR imaging in human breast cancer. Their target tissue uptake, retention, and uptake selectivity were studied in female rats. The distribution studies revealed that PR-mediated uptake in the uterus and ovaries could only be demonstrated for Z-[ 123 I]IPG2. The target tissue uptake selectivity was, however, low, with the highest uterus-to-nontarget tissue uptake ratios observed at 2-4 h postinjection (p.i.), being 4.4, 1.8, and 7.4 for the uterus-to-blood, -fat, and -muscle ratio, respectively. For Z-[ 123 I]IPG2, distribution was also studied in dimethylbenzanthracene (DMBA)-induced mammary tumour-bearing rats and in normal rabbits. Mammary tumour uptake of Z-[ 123 I]IPG2 in the mammary tumour-bearing rat was also found to be PR-specific. In rabbits, higher selective target tissue uptake of Z-[ 123 I]IPG2 was observed than in rats, resulting in uterus-to-blood, -fat, and -muscle ratios of 6.6, 2.2, and 21.3 at 2-4 h p.i., respectively. In conclusion, Z-[ 123 I]IPG2, which displayed high binding affinity for both the human and rat PR in vitro, showed specific PR-mediated target tissue uptake in rats and rabbits in vivo, the uptake selectivity being highest in the latter. Because the binding characteristics appeared to vary between species, a pilot study in breast cancer patients may be needed to decide whether Z-[ 123 I]IPG2 can be of potential use as PR imaging agent in breast cancer

  10. Determine equilibrium dissociation constant of drug-membrane receptor affinity using the cell membrane chromatography relative standard method.

    Science.gov (United States)

    Ma, Weina; Yang, Liu; Lv, Yanni; Fu, Jia; Zhang, Yanmin; He, Langchong

    2017-06-23

    The equilibrium dissociation constant (K D ) of drug-membrane receptor affinity is the basic parameter that reflects the strength of interaction. The cell membrane chromatography (CMC) method is an effective technique to study the characteristics of drug-membrane receptor affinity. In this study, the K D value of CMC relative standard method for the determination of drug-membrane receptor affinity was established to analyze the relative K D values of drugs binding to the membrane receptors (Epidermal growth factor receptor and angiotensin II receptor). The K D values obtained by the CMC relative standard method had a strong correlation with those obtained by the frontal analysis method. Additionally, the K D values obtained by CMC relative standard method correlated with pharmacological activity of the drug being evaluated. The CMC relative standard method is a convenient and effective method to evaluate drug-membrane receptor affinity. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Depletion of calcium stores contributes to progesterone-induced attenuation of calcium signaling of G protein-coupled receptors

    Czech Academy of Sciences Publication Activity Database

    Gehrig-Burger, K.; Slaninová, Jiřina; Gimpl, G.

    2010-01-01

    Roč. 67, č. 16 (2010), s. 2815-2824 ISSN 1420-682X Institutional research plan: CEZ:AV0Z40550506 Keywords : non-genomic effect * oxytocin * bradykinin * progesterone Subject RIV: CC - Organic Chemistry Impact factor: 7.047, year: 2010

  12. Dynamics of glycine receptor insertion in the neuronal plasma membrane.

    Science.gov (United States)

    Rosenberg, M; Meier, J; Triller, A; Vannier, C

    2001-07-15

    The exocytosis site of newly synthesized glycine receptor was defined by means of a morphological assay to characterize its export from the trans-Golgi Network to the plasma membrane. This was achieved by expressing in transfected neurons an alpha1 subunit bearing an N-terminal tag selectively cleavable from outside the cell by thrombin. This was combined with a transient temperature-induced block of exocytic transport that creates a synchronized exocytic wave. Immunofluorescence microscopy analysis of the cell surface appearance of newly synthesized receptor revealed that exocytosis mainly occurred at nonsynaptic sites in the cell body and the initial portion of dendrites. At the time of cell surface insertion, the receptors existed as discrete clusters. Quantitative analysis showed that glycine receptor clusters are stable in size and subsequently appeared in more distal dendritic regions. This localization resulted from diffusion in the plasma membrane and not from exocytosis of transport vesicles directed to dendrites. Kinetic analysis established a direct substrate-product relationship between pools of somatic and dendritic receptors. This indicated that clusters represent intermediates between newly synthesized and synaptic receptors. These results support a diffusion-retention model for the formation of receptor-enriched postsynaptic domains and not that of a vectorial intracellular targeting to synapses.

  13. Protein receptor-independent plasma membrane remodeling by HAMLET

    DEFF Research Database (Denmark)

    Nadeem, Aftab; Sanborn, Jeremy; Gettel, Douglas L.

    2015-01-01

    A central tenet of signal transduction in eukaryotic cells is that extra-cellular ligands activate specific cell surface receptors, which orchestrate downstream responses. This "protein-centric" view is increasingly challenged by evidence for the involvement of specialized membrane domains in sig...

  14. Dimer-based model for heptaspanning membrane receptors.

    Science.gov (United States)

    Franco, Rafael; Casadó, Vicent; Mallol, Josefa; Ferré, Sergi; Fuxe, Kjell; Cortés, Antonio; Ciruela, Francisco; Lluis, Carmen; Canela, Enric I

    2005-07-01

    The existence of intramembrane receptor-receptor interactions for heptaspanning membrane receptors is now fully accepted, but a model considering dimers as the basic unit that binds to two ligand molecules is lacking. Here, we propose a two-state-dimer model in which the ligand-induced conformational changes from one component of the dimer are communicated to the other. Our model predicts cooperativity in binding, which is relevant because the other current models fail to address this phenomenon satisfactorily. Our two-state-dimer model also predicts the variety of responses elicited by full or partial agonists, neutral antagonists and inverse agonists. This model can aid our understanding of the operation of heptaspanning receptors and receptor channels, and, potentially, be important for improving the treatment of cardiovascular, neurological and neuropsychyatric diseases.

  15. Sex-specific effects of daily gavage with a mixed progesterone and glucocorticoid receptor antagonist on hypoxic ventilatory response in newborn rats.

    Science.gov (United States)

    Fournier, Stéphanie; Doan, Van Diep; Joseph, Vincent

    2012-01-01

    We tested the hypothesis that daily gavage with mifepristone, a mixed progesterone/glucocorticoid receptor antagonist would alter hypoxic ventilatory response (HVR) in newborn male and female rats. Rats were treated with mifepristone (40µg/g/day), or vehicle between postnatal days 3-12, and used at 10-12 days of age to record baseline ventilatory and metabolic values using whole body plethysmography. HVR was tested by exposing the animals to 14% and 12% O(2) for 20 minutes each. HVR was enhanced by mifepristone treatment, mainly due to an effect on tidal volume that remained higher in mifepristone treated rats during both levels of hypoxic exposure. This effect was sex-specific being apparent only in male rats. In Vehicle treated rats, HVR was higher in females than in males, which was also due to a higher tidal volume in hypoxia (at 14 and 12% O(2)). We conclude that the activity of the progesterone and/or glucocorticoid receptors modulates respiratory control in rat pups, and that these effects are different in males and females.

  16. Sexual maturation, serum steroid concentrations, and mRNA expression of IGF-1, luteinizing and progesterone hormone receptors and survivin gene in Japanese quail hens.

    Science.gov (United States)

    Shit, N; Sastry, K V H; Singh, R P; Pandey, N K; Mohan, J

    2014-03-15

    In avian species, sexual maturation represents the evidence of start laying, which is a consequence of the development of ovarian follicles. These follicles are the functional reproductive unit whose maturation and viability critically depends on endocrine, paracrine, and autocrine factors beyond the signals from the central nervous system. The present study was undertaken to investigate the correlation of sexual maturity with tissue growth, mRNA expression of certain genes, and serum steroid concentrations in Japanese quail hens. To carry out the present study, a total of forty Japanese quail hens (5 weeks) were housed individually under uniform husbandry condition with ad libitum quail layer ration and water at 14-hour photo schedule. On sixth week onwards, four birds were sacrificed at each time on 1, 3, 7, 10, 13, 16, 19, 22, 25, and 28 days. Serum was extracted aseptically to analyze the gonadal steroid hormones (estrogen and progesterone) and corticosterone to investigate the liaison with sexual maturation of the species. Expression analyses of four genes i.e., insulin-like growth factor-1, luteinizing hormone receptor, progesterone receptor, and survivin were carried out in the three largest ovarian yellow follicles. A significant (P Japanese quail may be completed by the time of 8 weeks after its birth in support of the analyzed information studied in the current investigation. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Endocytosis of GPI-linked membrane folate receptor-alpha.

    Science.gov (United States)

    Rijnboutt, S; Jansen, G; Posthuma, G; Hynes, J B; Schornagel, J H; Strous, G J

    1996-01-01

    GPI-linked membrane folate receptors (MFRs) have been implicated in the receptor-mediated uptake of reduced folate cofactors and folate-based chemotherapeutic drugs. We have studied the biosynthetic transport to and internalization of MFR isoform alpha in KB-cells. MFR-alpha was synthesized as a 32-kD protein and converted in a maturely glycosylated 36-38-kD protein 1 h after synthesis. 32-kD MFR-alpha was completely soluble in Triton X-100 at 0 degree C. In contrast, only 33% of the 36-38-kD species could be solubilized at these conditions whereas complete solubilization was obtained in Triton X-100 at 37 degrees C or in the presence of saponin at 0 degree C. Similar solubilization characteristics were found when MFR-alpha at the plasma membrane was labeled with a crosslinkable 125I-labeled photoaffinity-analog of folic acid as a ligand. Triton X-100-insoluble membrane domains containing MFR-alpha could be separated from soluble MFR-alpha on sucrose flotation gradients. Only Triton X-100 soluble MFR-alpha was internalized from the plasma membrane. The reduced-folate-carrier, an integral membrane protein capable of translocating (anti-)folates across membranes, was completely excluded from the Triton X-100-resistant membrane domains. Internalized MFR-alpha recycled slowly to the cell surface during which it remained soluble in Triton X-100 at 0 degree C. Using immunoelectron microscopy, we found MFR-alpha along the entire endocytic pathway: in clathrin-coated buds and vesicles, and in small and large endosomal vacuoles. In conclusion, our data indicate that a large fraction, if not all, of internalizing MFR-alpha bypasses caveolae.

  18. Use of Membrane Potential to Achieve Transmembrane Modification with an Artificial Receptor.

    Science.gov (United States)

    Hatanaka, Wataru; Kawaguchi, Miki; Sun, Xizheng; Nagao, Yusuke; Ohshima, Hiroyuki; Hashida, Mitsuru; Higuchi, Yuriko; Kishimura, Akihiro; Katayama, Yoshiki; Mori, Takeshi

    2017-02-15

    We developed a strategy to modify cell membranes with an artificial transmembrane receptor. Coulomb force on the receptor, caused by the membrane potential, was used to achieve membrane penetration. A hydrophobically modified cationic peptide was used as a membrane potential sensitive region that was connected to biotin through a transmembrane oligoethylene glycol (OEG) chain. This artificial receptor gradually disappeared from the cell membrane via penetration despite the presence of a hydrophilic OEG chain. However, when the receptor was bound to streptavidin (SA), it remained on the cell membrane because of the large and hydrophilic nature of SA.

  19. Progesterone inhibition of oxytocin signaling in endometrium

    Directory of Open Access Journals (Sweden)

    Cecily Vauna Bishop

    2013-08-01

    Full Text Available Expression of the oxytocin receptor (OXTR in the endometrium of ruminant species is regulated by the ovarian steroids progesterone (P and estradiol (E. Near the end of the estrous cycle, long-term exposure of endometrial epithelial cells to P results in loss of genomic P receptors (PGRs, leading to an increase in E receptors (ERs. Genomic regulation of the OXTR is mediated via suppression of ER signaling by P. Upon OT binding at the plasma membrane of endometrial cells, a signaling cascade is generated stimulating release of prostaglandin F2alpha (PGF2alpha. Transport of PGF2alpha to the ovary results in release of OT by luteal cells in a positive feedback loop leading to luteal regression. This signaling cascade can be rapidly blocked by exposing endometrial cells to physiologic levels of P. This mini review will focus on the mechanisms by which P may act to block OXTR signaling and the luteolytic cascade in the ruminant endometrium, with special focus on both non-genomic signaling pathways and non-receptor actions of P at the level of the plasma membrane. While this review focuses on ruminant species, non-classical blockage of OXTR signaling may be important for fertility in women.

  20. Role of CYP27A1 in progesterone metabolism in vitro and in vivo.

    OpenAIRE

    Escher Geneviève; Vögeli Isabelle; Escher Robert; Tuckey Robert C; Erickson Sandra; Krozowski Zygmunt; Frey Felix J

    2009-01-01

    In the kidney progesterone is inactivated to 20alpha dihydro progesterone (20alpha DH progesterone) to protect the mineralocorticoid receptor from progesterone excess. In an attempt to clone the enzyme with 20alpha hydroxysteroid activity using expression cloning in CHOP cells and a human kidney expression library serendipitously cDNA encoding CYP27A1 was isolated. Overexpression of CYP27A1 in CHOP cells decreased progesterone conversion to 20alpha DH progesterone in a dose dependent manner a...

  1. Progesterone radioimmunoassay

    International Nuclear Information System (INIS)

    Stroufova, A.; Kozlova, J.

    1976-01-01

    RIA methods of determining progestorone using the SORIN kit made in Italy and the NEN kit made in Great Britain were compared. Plasma extraction, the initial sample size for examination and recovery, the range of calibration curves of the two kits, the variation coefficient, the values of the blank sample and the values of progesterone determined in the normal menstrual cycle are discussed in detail. Variation coefficient: Sorin (calibration curve 9 to 11%, biological material 9.2%), NEN (calibration curve 12%, biological material 27.8%); determinations of progesterone levels during a normal menstrual cycle were 10 to 15% higher with the NEN kit; tritiated samples were measured with a 30 to 37% efficiency using the SORIN kit and 15 to 18% efficiency using the NEN kit. The turbidity and later sediment which formed during the determination of steroid hormones in biological materials after the addition of the scintillation solution did not reduce the efficiency of measurement. Priority is given to the SORIN kit. (L.O.)

  2. Effect of levonorgestrel IUD and oral medroxyprogesterone acetate on glandular and stromal progesterone receptors (PRA and PRB), and estrogen receptors (ER-alpha and ER-beta) in human endometrial hyperplasia.

    Science.gov (United States)

    Vereide, Anne Beate; Kaino, Turid; Sager, Georg; Arnes, Marit; Ørbo, Anne

    2006-05-01

    The effect on progesterone and estrogen receptor expression in glands and stroma after two different treatment regimens of endometrial hyperplasia was determined. Pre- and post-treatment paraffin-embedded endometrial hyperplasia specimens from women treated with levonorgestrel (LNG) intrauterine device (n = 21) and women treated with 10 mg medroxyprogesterone acetate (MPA) for 10 days per cycle (n = 29) were examined immunohistochemically and evaluated by H-score (a semi-quantitative microscopical method evaluating staining intensity and number of stained cells, scale 0-3) for changes in expression of PRA (progesterone receptor A), PRB (progesterone receptor B), ER-alpha (estrogen receptor-alpha), ER-beta (estrogen receptor-beta) and AR (androgen receptors) after 3 months of treatment. All the patients in the LNG IUD group responded to treatment with no sign of hyperplasia after 3 months, while only about half of the patients given MPA orally responded. Expression of PRA, PRB, ER-alpha and ER-beta were markedly reduced after progestin treatment in both treatment groups but the reduction was much more pronounced in the LNG group (H-score for PRA was reduced from 2.61 to 0.11 in glands and from 2.26 to 0.09 in stroma in LNG group. Corresponding reduction for PRB in the LNG group was from 1.96 to 0.11 and from 0.83 to 0.01. PRA was reduced from 2.53 to 1.78 in glands and from 1.93 to 1.30 in stroma in the MPA group. Corresponding reduction for PRB in the MPA group was from 2.02 to 1.25 in glands and from 0.80 to 0.34 in stroma). Weak and focal stromal expression of AR was demonstrated in 22% of the specimens before but not after therapy. There was a statistically significant reduction in both PR and ER among the responders whereas non-responders showed no statistical change after treatment. The present study shows that LNG IUD causes an almost complete down-regulation (lack of immunohistochemical expression) of PR expression and a considerable down-regulation of ER

  3. Abnormal excessive per vagina (PV) bleeding on Esmya-selective progesterone receptor modulator (SPRM) in a symptomatic patient with uterine fibroid.

    Science.gov (United States)

    Matytsina-Quinlan, Lyubov; Matytsina, Laura

    2015-05-14

    A woman in her late 40s presented with excessive per vagina (PV) bleeding and uterine fibroid. She reported excessive PV bleeding after starting Esmya; she was brought in by ambulance to the emergency department with profuse bleeding. Abnormal uterine bleeding (AUB) developed after selective progesterone receptor modulator (SPRM) administration in this symptomatic patient with uterine fibroid. The drug was withheld and surgical treatment considered. Progressive deterioration of PV bleeding after receiving SPRM led to an urgent laparoscopic total hysterectomy, which had to be postponed due to severe anaemia. Surgery took place regardless because the excessive bleeding continued. Histology revealed a 6 cm submucosal uterine fibroid (SMUF) and adenomyosis. Physicians prescribing SPRMs to stop PV bleeding should be aware of potential AUB, which could lead to urgent hysterectomy. The mechanism of action of SPRMs is not clearly understood. Awareness of the side effects of Esmya, such as AUB, must be kept in mind when administering SPRMs. 2015 BMJ Publishing Group Ltd.

  4. Pesquisa de estrógeno e progesterona no epitélio das pregas vocais de mulheres por imunohistoquímica Immunohistochemical searching for estrogen and progesterone receptors in women vocal fold epithelia

    Directory of Open Access Journals (Sweden)

    Oswaldo Angel Bellido Rios

    2008-08-01

    Full Text Available A laringe é extremamente sensível a mudanças endocrinológicas. A maioria das alterações da mucosa das pregas vocais é causada por modificações do conteúdo líquido das pregas vocais e das suas modificações epiteliais. O estrógeno e a progesterona interferem e modificam esse conteúdo líquido das pregas vocais. O objetivo deste trabalho é verificar a presença de receptores de estrógeno e progesterona no epitélio das pregas vocais de mulheres. MATERIAL E MÉTODO: Estudo de casos prospectivos. Foram realizados exames de imunohistoquímica para receptores de estrógeno e progesterona em 19 espécimes de epitélio de pregas vocais que não apresentavam quaisquer indícios de afecção, inclusive inflamatória. Foram descartados casos de pacientes com idade superior a 40 anos e inferior a 15 anos. RESULTADOS: Foram encontrados receptores para progesterona em 18 de 19 pacientes. Os receptores de progesterona estão localizados tanto no núcleo quanto no citoplasma e principalmente na camada basal. Não houve nenhum caso de receptores de estrógeno nas pregas vocais. CONCLUSÃO: O epitélio das pregas vocais apresenta receptores para progesterona, tanto no citoplasma quanto no núcleo. Não foram encontrados receptores para estrógeno no epitélio das pregas vocais estudadas.Larynx is extremely sensitive to endocrinologic changes. Most vocal fold mucosa alterations are caused by changes in vocal fold liquid content and its epithelial changes. Estrogen and progesterone interfere and change this liquid content in the vocal folds. Our goal with the present paper is to study the presence of estrogen and progesterone receptors on vocal fold epithelium in 19 vocal fold epithelium specimens that did not present any indication of disease, especially inflammatory disease. We discarded those cases of patients above 40 years of age and those below 15. RESULTS: we found progesterone receptors in 18 of the 19 patients. The progesterone receptors

  5. Interleukin (IL)-1 in rat parturition: IL-1 receptors 1 and 2 and accessory proteins abundance in pregnant rat uterus at term - regulation by progesterone.

    Science.gov (United States)

    Ishiguro, Tomohito; Takeda, Jun; Fang, Xin; Bronson, Heather; Olson, David M

    2016-07-01

    The role of interleukin-1 (IL-1), a pro-inflammatory cytokine, in parturition is typically noted by changes in its concentrations. Studying the expression of its receptor family, IL-1 receptor (IL-1R) 1, IL-1R2, IL-1R accessory protein (IL-1RAcP), and its predominantly brain isoform, IL-1RAcPb, during late gestation in the uterus in the Long-Evans rat is another. We assessed changes in their mRNA and protein relative abundance in the uterus and compared IL-1RAcP and IL-1RAcPb mRNA abundance in uterus, cervix, ovaries, placenta, and whole blood of Long-Evans rats during late gestation or in RU486 and progesterone-treated dams using quantitative real-time PCR and western immunoblotting. IL-1R1, IL-1RAcP, and IL-1RAcPb mRNA abundance significantly increased in the uterus at delivery whereas IL-1R2 mRNA abundance significantly decreased. IL-1R1 protein increased at term and IL-1R2 protein decreased at term compared to nonpregnant uteri. IL1-RAcPb mRNA abundance was less than IL-1RAcP, but in the lower uterine segment it was the highest of all tissues examined. RU486 stimulated preterm delivery and an increase in IL-1R1 mRNA abundance whereas progesterone administration extended pregnancy and suppressed the increase in IL-1R1. These data suggest that changes in uterine sensitivity to IL-1 occur during late gestation and suggest another level of regulation for the control of delivery. The roles for IL-1RAcP and IL-1RAcPb need to be determined, but may relate to different intracellular signaling pathways. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  6. expression of oestrogen and progesterone

    African Journals Online (AJOL)

    2001-07-02

    Jul 2, 2001 ... cancer may be more aggressive in the sub-Saharan female than in her Western counterpart. The aggressiveness of a tumour is dependent upon several factors. These include tumour size, histological type and grade, oestrogen and progesterone receptor status, proliferation rate, DNA ploidy and disease ...

  7. Hypermethylation pattern of ESR and PgR genes and lacking estrogen and progesterone receptors in human breast cancer tumors: ER/PR subtypes.

    Science.gov (United States)

    Pirouzpanah, Saeed; Taleban, Forough-Azam; Mehdipour, Parvin; Sabour, Siamak; Atri, Morteza

    2018-02-14

    The option of endocrine therapy in breast cancer remains conventionally promising. We aimed to investigate how accurately the pattern of hypermethylation at estrogen receptor (ESR) and progesterone receptor (PgR) genes may associate with relative expression and protein status of ER, PR and the combinative phenotype of ER/PR. In this consecutive case-series, we enrolled 139 primary diagnosed breast cancer. Methylation specific PCR was used to assess the methylation status (individual test). Tumor mRNA expression levels were evaluated using real-time RT-PCR. Immunohistochemistry data was used to present hormonal receptor status of a tumor (as test reference). Methylation at ESR1 was comparably frequent in ER-breast tumors (83.0%, PPR- conditions (Cramer's V= 0.44, PPR (77.1%, PPR expressions (55.6%, PPR- (64.4%, PPR-, the hypermethylation of PgRb seem another epigenetic signalling variable actively associate with methylated ESR1 to show lack of ER+/PR+ tumors in breast cancer.

  8. X-ray structures of progesterone receptor ligand binding domain in its agonist state reveal differing mechanisms for mixed profiles of 11β-substituted steroids.

    Science.gov (United States)

    Lusher, Scott J; Raaijmakers, Hans C A; Vu-Pham, Diep; Kazemier, Bert; Bosch, Rolien; McGuire, Ross; Azevedo, Rita; Hamersma, Hans; Dechering, Koen; Oubrie, Arthur; van Duin, Marcel; de Vlieg, Jacob

    2012-06-08

    We present here the x-ray structures of the progesterone receptor (PR) in complex with two mixed profile PR modulators whose functional activity results from two differing molecular mechanisms. The structure of Asoprisnil bound to the agonist state of PR demonstrates the contribution of the ligand to increasing stability of the agonist conformation of helix-12 via a specific hydrogen-bond network including Glu(723). This interaction is absent when the full antagonist, RU486, binds to PR. Combined with a previously reported structure of Asoprisnil bound to the antagonist state of the receptor, this structure extends our understanding of the complex molecular interactions underlying the mixed agonist/antagonist profile of the compound. In addition, we present the structure of PR in its agonist conformation bound to the mixed profile compound Org3H whose reduced antagonistic activity and increased agonistic activity compared with reference antagonists is due to an induced fit around Trp(755), resulting in a decreased steric clash with Met(909) but inducing a new internal clash with Val(912) in helix-12. This structure also explains the previously published observation that 16α attachments to RU486 analogs induce mixed profiles by altering the binding of 11β substituents. Together these structures further our understanding of the steric and electrostatic factors that contribute to the function of steroid receptor modulators, providing valuable insight for future compound design.

  9. Expression of somatostatin, dopamine, progesterone and growth hormone receptor mRNA in canine cortisol-secreting adrenocortical tumours

    NARCIS (Netherlands)

    Kool, Miriam M J; Galac, Sara; van der Helm, Noortje; Spandauw, Catharina G; Kooistra, Hans S; Mol, Jan A

    2015-01-01

    Cortisol-secreting adrenocortical tumours (AT) in dogs are characterised by uncontrolled growth and excessive cortisol secretion. Dysregulated hormone receptor expression might be involved in tumour growth and hypersecretion of cortisol. The relative mRNA expression of growth hormone receptor,

  10. The effect of 7 days of letrozole pretreatment combined with misoprostol on the expression of progesterone receptor and apoptotic factors of placental and decidual tissues from first-trimester abortion: a randomized controlled trial.

    Science.gov (United States)

    Yung, Sofie Shuk Fei; Lee, Vivian Chi Yan; Chiu, Philip Chi Ngong; Li, Hang Wun Raymond; Ng, Ernest Hung Yu; Yeung, William Shu Biu; Ho, Pak Chung

    2016-04-01

    To evaluate if letrozole-induced suppression of estradiol reduces progesterone receptor expression and apoptosis in the first-trimester placenta. We performed a double-blinded, randomized, placebo-controlled trial. We randomized 20 women requesting first-trimester abortion with gestation up to 63 days to receive either letrozole 10 mg daily or placebo pretreatment for 7 days before administrating 400 mcg of vaginal misoprostol followed by suction abortion. We collected the placental and decidual tissues on which we performed immunohistochemical staining for progesterone receptor and apoptotic markers (active caspase 3, caspase 3, Bcl2, CD95, fas ligand) and determined H-scores of each based on the intensities of staining. We performed terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL) assay for apoptosis in the samples of four women to confirm the findings from apoptotic markers. We excluded one woman in the letrozole group from the analysis because she had passage of abortus after taking letrozole, leaving 19 women (9 in the letrozole group, 10 in the placebo group) for analysis. There was no significant difference in the H-scorings of progesterone receptor and apoptotic markers, as well as proportion of apoptotic cells on TUNEL assay between the two groups. The H-scores for the progesterone receptor were 8.17 ± 2.67 (mean ± SD) in the letrozole group and 9.01 ± 2.82 in the placebo group (p=0.36). We did not detect a difference in the expression of progesterone receptor and apoptotic markers in placental and decidual tissues after letrozole pretreatment for 7 days in first-trimester abortion. We did not confirm the hypothesis that letrozole reduces progesterone receptor expression and induces apoptosis in the first-trimester placenta. Further studies are required to allow better understanding of the mechanism by which estrogen suppression following the use of letrozole can lead to improved abortion rate in the first

  11. Progesterone Signaling Mechanisms in Brain and Behavior

    Science.gov (United States)

    Mani, Shaila K.; Oyola, Mario G.

    2011-01-01

    Steroid hormone, progesterone, modulates neuroendocrine functions in the central nervous system resulting in alterations in physiology and behavior. These neuronal effects are mediated primarily by intracellular progestin receptors (PRs) in the steroid-sensitive neurons, resulting in transcription-dependent genomic actions (classical mechanism). In addition to progesterone, intracellular PRs can also be activated in a “ligand-independent” manner by neurotransmitters, peptide growth factors, cyclic nucleotides, and neurosteroids. Recent studies indicate that rapid, non-classical progesterone actions involving cytoplasmic kinase signaling and/or extranuclear PRs can result in both transcription-independent and transcription-dependent actions. Cross-talk between extranuclear and classical intracellular signaling pathways promotes progesterone-dependent behavior in mammals. This review focuses on the mechanisms by which progesterone-initiated signaling mechanisms converge with PRs in the brain to modulate reproductive behavior in female rodents. PMID:22649404

  12. Confirmation of 5p12 as a susceptibility locus for progesterone-receptor- positive, lower grade breast cancer

    NARCIS (Netherlands)

    R.L. Milne (Roger); E.L. Goode (Ellen); M. García-Closas (Montserrat); F.J. Couch (Fergus); G. Severi (Gianluca); R. Hein (Rebecca); Z. Fredericksen (Zachary); N. Malats (Núria); M.P. Zamora (Pilar); J.I.A. Perez (Jose Ignacio Arias); J. Benítez (Javier); T. Dörk (Thilo); P. Schürmann (Peter); J.H. Karstens (Johann); P. Hillemanns (Peter); A. Cox (Angela); I.W. Brock (Ian); K.S. Elliot (Katherine); S.S. Cross (Simon); S. Seal (Sheila); C. Turnbull (Clare); A. Renwick (Anthony); N. Rahman (Nazneen); C-Y. Shen (Chen-Yang); J-C. Yu (Jyh-Cherng); C.-S. Huang (Chiun-Sheng); M.-F. Hou (Ming-Feng); B.G. Nordestgaard (Børge); S.E. Bojesen (Stig); C. Lanng (Charlotte); G.G. Alnæs (Grethe); V. Kristensen (Vessela); A.-L. Børrensen-Dale (Anne-Lise); J.L. Hopper (John); G.S. Dite (Gillian); C. Apicella (Carmel); M.C. Southey (Melissa); D. Lambrechts (Diether); B.T. Yesilyurt (Betül); O.A.M. Floris; K. Leunen; S. Sangrajrang (Suleeporn); V. Gaborieau (Valerie); P. Brennan (Paul); J.D. McKay (James); J. Chang-Claude (Jenny); S. Wang-Gohrke (Shan); P. Radice (Paolo); P. Peterlongo (Paolo); S. Manoukian (Siranoush); M. Barile (Monica); G.G. Giles (Graham); L. Baglietto (Laura); E.M. John (Esther); A. Miron (Alexander); S.J. Chanock (Stephen); J. Lissowska (Jolanta); M.E. Sherman (Mark); J.D. Figueroa (Jonine); N.V. Bogdanova (Natalia); N.N. Antonenkova (Natalia); I.V. Zalutsky (Iosif); Y.I. Rogov (Yuri); P.A. Fasching (Peter); T. Bayer (T.); A.B. Ekici (Arif); M.W. Beckmann (Matthias); H. Brenner (Hermann); H. Müller (Heike); V. Arndt (Volker); C. Stegmaier (Christa); I.L. Andrulis (Irene); J.A. Knight (Julia); G. Glendon (Gord); A.M. Mulligan (Anna Marie); A. Mannermaa (Arto); V. Kataja (Vesa); V-M. Kosma (Veli-Matti); J. Hartikainen (Jaana); A. Meindl (Alfons); J. Heil (Joerg); C.R. Bartram (Claus); R.K. Schmutzler (Rita); G. Thomas (Gilles); R.N. Hoover (Robert); O. Fletcher (Olivia); L.J. Gibson (Lorna); I. dos Santos Silva (Isabel); J. Peto (Julian); S. Nickels (Stefan); D. Flesch-Janys (Dieter); H. Anton-Culver (Hoda); A. Ziogas (Argyrios); E.J. Sawyer (Elinor); I.P. Tomlinson (Ian); M. Kerin (Michael); N. Miller (Nicola); M.K. Schmidt (Marjanka); A. Broeks (Annegien); L.J. van 't Veer (Laura); R.A.E.M. Tollenaar (Rob); P.D.P. Pharoah (Paul); A.M. Dunning (Alison); K.A. Pooley (Karen); F. Marme (Federick); A. Schneeweiss (Andreas); C. Sohn (Christof); B. Burwinkel (Barbara); A. Jakubowska (Anna); J. Lubinski (Jan); K. Jaworska (Katarzyna); K. Durda (Katarzyna); D. Kang (Daehee); K-Y. Yoo (Keun-Young); D-Y. Noh (Dong-Young); S.-H. Ahn (Sei-Hyun); D. Hunter (David); S.E. Hankinson (Susan); P. Kraft (Peter); S. Lindstrom (Stephen); X. Chen (Xiaoqing); J. Beesley (Jonathan); U. Hamann (Ute); V. Harth (Volker); C. Justenhoven (Christina); R. Winqvist (Robert); K. Pykäs (Katri); A. Jukkola-Vuorinen (Arja); M. Grip (Mervi); M.J. Hooning (Maartje); A. Hollestelle (Antoinette); R.A. Oldenburg (Rogier); M.M.A. Tilanus-Linthorst (Madeleine); E.K. Khusnutdinova (Elza); M. Bermisheva (Marina); D. Prokofieva (Darya); A. Farahtdinova (Albina); J.E. Olson (Janet); X. Wang (Xing); M.K. Humphreys (Manjeet); Q. Wang (Qing); G. Chenevix-Trench (Georgia); D.F. Easton (Douglas)

    2011-01-01

    textabstractBackground: The single-nucleotide polymorphism (SNP) 5p12-rs10941679 has been found to be associated with risk of breast cancer, particularly estrogen receptor (ER)-positive disease. We aimed to further explore this association overall, and by tumor histopathology, in the Breast Cancer

  13. Confirmation of 5p12 As a Susceptibility Locus for Progesterone-Receptor-Positive, Lower Grade Breast Cancer

    NARCIS (Netherlands)

    Milne, Roger L.; Goode, Ellen L.; Garca-Closas, Montserrat; Couch, Fergus J.; Severi, Gianluca; Hein, Rebecca; Fredericksen, Zachary; Malats, Nuria; Pilar Zamora, M.; Arias Perez, Jose Ignacio; Benitez, Javier; Doerk, Thilo; Schuermann, Peter; Karstens, Johann H.; Hillemanns, Peter; Cox, Angela; Brock, Ian W.; Elliot, Graeme; Cross, Simon S.; Seal, Sheila; Turnbull, Clare; Renwick, Anthony; Rahman, Nazneen; Shen, Chen-Yang; Yu, Jyh-Cherng; Huang, Chiun-Sheng; Hou, Ming-Feng; Nordestgaard, Borge G.; Bojesen, Stig E.; Lanng, Charlotte; Alnaes, Grethe Grenaker; Kristensen, Vessela; Borrensen-Dale, Anne-Lise; Hopper, John L.; Dite, Gillian S.; Apicella, Carmel; Southey, Melissa C.; Lambrechts, Diether; Yesilyurt, Betul T.; Floris, Giuseppe; Leunen, Karin; Sangrajrang, Suleeporn; Gaborieau, Valerie; Brennan, Paul; McKay, James; Chang-Claude, Jenny; Wang-Gohrke, Shan; Radice, Paolo; Peterlongo, Paolo; Manoukian, Siranoush; Barile, Monica; Giles, Graham G.; Baglietto, Laura; John, Esther M.; Miron, Alexander; Chanock, Stephen J.; Lissowska, Jolanta; Sherman, Mark E.; Figueroa, Jonine D.; Bogdanova, Natalia V.; Antonenkova, Natalia N.; Zalutsky, Iosif V.; Rogov, Yuri I.; Fasching, Peter A.; Bayer, Christian M.; Ekici, Arif B.; Beckmann, Matthias W.; Brenner, Hermann; Mueller, Heiko; Arndt, Volker; Stegmaier, Christa; Andrulis, Irene L.; Knight, Julia A.; Glendon, Gord; Mulligan, Anna Marie; Mannermaa, Arto; Kataja, Vesa; Kosma, Veli-Matti; Hartikainen, Jaana M.; Meindl, Alfons; Heil, Joerg; Bartram, Claus R.; Schmutzler, Rita K.; Thomas, Gilles D.; Hoover, Robert N.; Fletcher, Olivia; Gibson, Lorna J.; Silva, Isabel dos Santos; Peto, Julian; Nickels, Stefan; Flesch-Janys, Dieter; Anton-Culver, Hoda; Ziogas, Argyrios; Sawyer, Elinor; Tomlinson, Ian; Kerin, Michael; Miller, Nicola; Schmidt, Marjanka K.; Broeks, Annegien; Van't Veer, Laura J.; Tollenaar, Rob A. E. M.; Pharoah, Paul D. P.; Dunning, Alison M.; Pooley, Karen A.; Marme, Frederik; Schneeweiss, Andreas; Sohn, Christof; Burwinkel, Barbara; Jakubowska, Anna; Lubinski, Jan; Jaworska, Katarzyna; Durda, Katarzyna; Kang, Daehee; Yoo, Keun-Young; Noh, Dong-Young; Ahn, Sei-Hyun; Hunter, David J.; Hankinson, Susan E.; Kraft, Peter; Lindstrom, Sara; Chen, Xiaoqing; Beesley, Jonathan; Hamann, Ute; Harth, Volker; Justenhoven, Christina; Winqvist, Robert; Pylkas, Katri; Jukkola-Vuorinen, Arja; Grip, Mervi; Hooning, Maartje; Hollestelle, Antoinette; Oldenburg, Rogier A.; Tilanus-Linthorst, Madeleine; Khusnutdinova, Elza; Bermisheva, Marina; Prokofieva, Darya; Farahtdinova, Albina; Olson, Janet E.; Wang, Xianshu; Humphreys, Manjeet K.; Wang, Qin; Chenevix-Trench, Georgia; Easton, Douglas F.

    2011-01-01

    Background: The single-nucleotide polymorphism (SNP) 5p12-rs10941679 has been found to be associated with risk of breast cancer, particularly estrogen receptor (ER)-positive disease. We aimed to further explore this association overall, and by tumor histopathology, in the Breast Cancer Association

  14. Confirmation of 5p12 As a Susceptibility Locus for Progesterone-Receptor-Positive, Lower Grade Breast Cancer

    DEFF Research Database (Denmark)

    Milne, Roger L; Goode, Ellen L; García-Closas, Montserrat

    2011-01-01

    BACKGROUND: The single-nucleotide polymorphism (SNP) 5p12-rs10941679 has been found to be associated with risk of breast cancer, particularly estrogen receptor (ER)-positive disease. We aimed to further explore this association overall, and by tumor histopathology, in the Breast Cancer Associatio...

  15. Relationship between concentrations of progesterone, oxytocin, noradrenaline, gene expression and protein level for their receptors in corpus luteum during estrous cycle in the cow.

    Science.gov (United States)

    Rekawiecki, R; Nowocin, A; Kotwica, J

    2010-06-01

    The aim of these studies was to evaluate of the relationship between luteal concentrations of oxytocin (OT), noradrenaline (NA), progesterone (P4), oxytocin receptors (OT-R) and beta(2)-adrenoreceptors (beta(2)-R) gene expression and their protein level throughout the estrous cycle in cattle. Corpora lutea (CL) collected during days 1-5, 6-10, 11-16 and 17-21 of the estrous cycle were used in these studies. Concentrations of P4, OT and NA were determined in tissue extracts. Gene expression and protein level for OT-R and beta(2)-R were investigated by RT-PCR and Western blot, respectively. Luteal concentration of P4 was higher (Pcycle. Concentration of OT was the highest on days 1-5 and 6-10 of the estrous cycle. This concentration decreased (Pcycle. Expression of OT-R mRNA was lower on days 6-16 (Pcycle, whereas it was similar or lower (Pcycle. Protein level for beta(2)-R was the highest on days 1-5 and decreased (Pcycle. Protein level for beta(2)-R was positively correlated (Pcycle. Copyright 2010 Elsevier Inc. All rights reserved.

  16. Nanodiscs for immobilization of lipid bilayers and membrane receptors: kinetic analysis of cholera toxin binding to a glycolipid receptor

    DEFF Research Database (Denmark)

    Borch, Jonas; Torta, Federico; Sligar, Stephen G

    2008-01-01

    nanodiscs and their incorporated membrane receptors can be attached to surface plasmon resonance sensorchips and used to measure the kinetics of the interaction between soluble molecules and membrane receptors inserted in the bilayer of nanodiscs. Cholera toxin and its glycolipid receptor G(M1) constitute...... partner cholera toxin B subunit to the receptor with the sensorchip-based surface plasmon resonance (SPR) technology. The measured stoichiometric and kinetic values of the interaction are in agreement with those reported by previous studies, thus providing proof-of-principle that nanodiscs can be employed...

  17. Progesterone receptor activates Msx2 expression by downregulating TNAP/Akp2 and activating the Bmp pathway in EpH4 mouse mammary epithelial cells.

    Directory of Open Access Journals (Sweden)

    Jodie M Fleming

    Full Text Available Previously we demonstrated that EpH4 mouse mammary epithelial cells induced the homeobox transcription factor Msx2 either when transfected with the progesterone receptor (PR or when treated with Bmp2/4. Msx2 upregulation was unaffected by Wnt inhibitors s-FRP or Dkk1, but was inhibited by the Bmp antagonist Noggin. We therefore hypothesized that PR signaling to Msx2 acts through the Bmp receptor pathway. Herein, we confirm that transcripts for Alk2/ActR1A, a non-canonical BmpR Type I, are upregulated in mammary epithelial cells overexpressing PR (EpH4-PR. Increased phosphorylation of Smads 1,5, 8, known substrates for Alk2 and other BmpR Type I proteins, was observed as was their translocation to the nucleus in EpH4-PR cells. Analysis also showed that Tissue Non-Specific Alkaline Phosphatase (TNAP/Akp2 was also found to be downregulated in EpH4-PR cells. When an Akp2 promoter-reporter construct containing a ½PRE site was transfected into EpH4-PR cells, its expression was downregulated. Moreover, siRNA mediated knockdown of Akp2 increased both Alk2 and Msx2 expression. Collectively these data suggest that PR inhibition of Akp2 results in increased Alk2 activity, increased phosphorylation of Smads 1,5,8, and ultimately upregulation of Msx2. These studies imply that re-activation of the Akp2 gene could be helpful in downregulating aberrant Msx2 expression in PR+ breast cancers.

  18. Absent progesterone receptor expression in the lymph node metastases of ER-positive, HER2-negative breast cancer is associated with relapse on tamoxifen.

    Science.gov (United States)

    Snell, Cameron E; Gough, Madeline; Middleton, Kathryn; Hsieh, Michael; Furnas, Lauren; Seidl, Brenton; Gibbons, Kristen; Pyke, Christopher; Shannon, Catherine; Woodward, Natasha; Armes, Jane E

    2017-11-01

    Progesterone receptor (PR) expression is prognostic in early stage breast cancer. There are several reports of discordant expression between primary tumour and axillary lymph node (ALN) metastasis expression of oestrogen receptor (ER) and PR. We sought to determine whether expression of these biomarkers in the synchronous ALN metastases of ER positive (+), HER2 negative (-) breast cancer could provide more accurate prognostic information. The retrospective cohort included 229 patients from a single institution with ER+, HER2- breast cancer who had synchronous ALN metastatic disease (2005-2014). PR expression was correlated with relapse-free survival, and subset analysis was performed for patients who received adjuvant tamoxifen or an aromatase inhibitor. One patient had an ER+ primary tumour, which was ER- in the ALN metastasis. 27 (11.3%) were PR- in the primary tumour and 56 (23.6%) in the ALN metastasis. The predominant change was from PR+ in the primary tumour to PR- in the lymph node. Absence of PR expression in the ALN was significantly associated with relapse; however, this was not the case in the primary tumour. In a subset analysis of patients taking adjuvant endocrine therapy, poorer prognosis was limited to those with PR- metastases on tamoxifen (HR=5.203, 95% CI 1.649 to 16.416, p=0.005). No significant prognostic effect of PR- metastases in patients taking aromatase inhibitors was seen (HR=1.519, 95% CI 0.675 to 3.418, p=0.312). Evaluation of PR expression in ALN metastasis may enable prediction of patients who are less likely to benefit from adjuvant tamoxifen. This study should be replicated in other cohorts. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  19. Differential regulation of breast cancer-associated genes by progesterone receptor isoforms PRA and PRB in a new bi-inducible breast cancer cell line.

    Science.gov (United States)

    Khan, Junaid A; Bellance, Catherine; Guiochon-Mantel, Anne; Lombès, Marc; Loosfelt, Hugues

    2012-01-01

    Progesterone receptor isoforms (PRA and PRB) are expressed at equal levels in normal mammary cells. However, alteration in PRA/PRB expression is often observed in aggressive breast cancer suggesting differential contribution of PR isoforms in carcinogenesis. The mechanisms underlying such processes remain to be established mainly due to paucity of appropriate cellular models. To investigate the role of PR isoforms and the impact of imbalanced PRA/PRB ratio in transcriptional regulation, we have generated an original human breast cancer cell line conditionally expressing PRA and/or PRB in dose-dependence of non-steroid inducers. We first focused on PR-dependent transcriptional regulation of the paracrine growth factor gene amphiregulin (AREG) playing important role in cancer. Interestingly, unliganded PRA increases AREG expression, independently of estrogen receptor, yet inhibitable by antiprogestins. We show that functional outcome of epidermal growth factor (EGF) on such regulation is highly dependent on PRA/PRB ratio. Using this valuable model, genome-wide transcriptomic studies allowed us to determine the differential effects of PRA and PRB as a function of hormonal status. We identified a large number of novel PR-regulated genes notably implicated in breast cancer and metastasis and demonstrated that imbalanced PRA/PRB ratio strongly impact their expression predicting poor outcome in breast cancer. In sum, our unique cell-based system strongly suggests that PRA/PRB ratio is a critical determinant of PR target gene selectivity and responses to hormonal/growth factor stimuli. These findings provide molecular support for the aggressive phenotype of breast cancers with impaired expression of PRA or PRB.

  20. Worse prognosis in breast cancer patients can be predicted by immunohistochemical analysis of positive MMP-2 and negative estrogen and progesterone receptors

    Directory of Open Access Journals (Sweden)

    Edneia A. S. Ramos

    Full Text Available Summary Introduction: Breast cancer is the most cause of death, and approximately 90% of these deaths are due to metastases. Matrix metalloproteinase-2 (MMP-2 gelatinase activity is able to degrade a major constituent of the tumor microenvironment, type IV collagen. Two well-established proteins used as markers in clinical practice for breast cancer are the receptors for estrogen (ER and progesterone (PR. Although the presence of these receptors has been associated with a better prognosis, loss of these proteins can occur during tumor progression, with subsequent resistance to hormone therapy. Objective: To study the correlation among MMP-2, ER, and PR, as well as the establishment of the metastatic process in primary breast tumors. Method: Breast cancer samples (n=44 were analyzed by immunohistochemistry for MMP-2, ER, and PR. Results: We observed that 90% of patients who had metastases and died showed positive staining for MMP-2 (p=0.0082 for both. Using Kaplan-Meier analysis, we found that negative ER patients who were also positive for MMP-2 had even worse disease-free survival (DFS and overall survival (OS (p= 0.012 and p=0.005, respectively. Similar results were found in PR-negative patients for DFS (a trend p=0.077 and OS (p=0.038. Conclusion: Regardless of our small sample size (n=44, the data obtained strongly suggest that MMP-2 in combination with already well-established markers could help to predict the emergence of metastases and death in patients with breast cancer.

  1. Conformational transitions and interactions underlying the function of membrane embedded receptor protein kinases.

    Science.gov (United States)

    Bocharov, Eduard V; Sharonov, Georgy V; Bocharova, Olga V; Pavlov, Konstantin V

    2017-09-01

    Among membrane receptors, the single-span receptor protein kinases occupy a broad but specific functional niche determined by distinctive features of the underlying transmembrane signaling mechanisms that are briefly overviewed on the basis of some of the most representative examples, followed by a more detailed discussion of several hierarchical levels of organization and interactions involved. All these levels, including single-molecule interactions (e.g., dimerization, liganding, chemical modifications), local processes (e.g. lipid membrane perturbations, cytoskeletal interactions), and larger scale phenomena (e.g., effects of membrane surface shape or electrochemical potential gradients) appear to be closely integrated to achieve the observed diversity of the receptor functioning. Different species of receptor protein kinases meet their specific functional demands through different structural features defining their responses to stimulation, but certain common patterns exist. Signaling by receptor protein kinases is typically associated with the receptor dimerization and clustering, ligand-induced rearrangements of receptor domains through allosteric conformational transitions with involvement of lipids, release of the sequestered lipids, restriction of receptor diffusion, cytoskeleton and membrane shape remodeling. Understanding of complexity and continuity of the signaling processes can help identifying currently neglected opportunities for influencing the receptor signaling with potential therapeutic implications. This article is part of a Special Issue entitled: Interactions between membrane receptors in cellular membranes edited by Kalina Hristova. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Receptor concentration and diffusivity control multivalent binding of Sv40 to membrane bilayers.

    Directory of Open Access Journals (Sweden)

    Oliwia M Szklarczyk

    Full Text Available Incoming Simian Virus 40 particles bind to their cellular receptor, the glycolipid GM1, in the plasma membrane and thereby induce membrane deformation beneath the virion leading to endocytosis and infection. Efficient membrane deformation depends on receptor lipid structure and the organization of binding sites on the internalizing particle. To determine the role of receptor diffusion, concentration and the number of receptors required for stable binding in this interaction, we analyze the binding of SV40 to GM1 in supported membrane bilayers by computational modeling based on experimental data. We measure the diffusion rates of SV40 virions in solution by fluorescence correlation spectroscopy and of the receptor in bilayers by single molecule tracking. Quartz-crystal microbalance with dissipation (QCM-D is used to measure binding of SV40 virus-like particles to bilayers containing the viral receptor GM1. We develop a phenomenological stochastic dynamics model calibrated against this data, and use it to investigate the early events of virus attachment to lipid membranes. Our results indicate that SV40 requires at least 4 attached receptors to achieve stable binding. We moreover find that receptor diffusion is essential for the establishment of stable binding over the physiological range of receptor concentrations and that receptor concentration controls the mode of viral motion on the target membrane. Our results provide quantitative insight into the initial events of virus-host interaction at the nanoscopic level.

  3. Genome-wide progesterone receptor binding: cell type-specific and shared mechanisms in T47D breast cancer cells and primary leiomyoma cells.

    Science.gov (United States)

    Yin, Ping; Roqueiro, Damian; Huang, Lei; Owen, Jonas K; Xie, Anna; Navarro, Antonia; Monsivais, Diana; Coon, John S; Kim, J Julie; Dai, Yang; Bulun, Serdar E

    2012-01-01

    Progesterone, via its nuclear receptor (PR), exerts an overall tumorigenic effect on both uterine fibroid (leiomyoma) and breast cancer tissues, whereas the antiprogestin RU486 inhibits growth of these tissues through an unknown mechanism. Here, we determined the interaction between common or cell-specific genome-wide binding sites of PR and mRNA expression in RU486-treated uterine leiomyoma and breast cancer cells. ChIP-sequencing revealed 31,457 and 7,034 PR-binding sites in breast cancer and uterine leiomyoma cells, respectively; 1,035 sites overlapped in both cell types. Based on the chromatin-PR interaction in both cell types, we statistically refined the consensus progesterone response element to G•ACA• • •TGT•C. We identified two striking differences between uterine leiomyoma and breast cancer cells. First, the cis-regulatory elements for HSF, TEF-1, and C/EBPα and β were statistically enriched at genomic RU486/PR-targets in uterine leiomyoma, whereas E2F, FOXO1, FOXA1, and FOXF sites were preferentially enriched in breast cancer cells. Second, 51.5% of RU486-regulated genes in breast cancer cells but only 6.6% of RU486-regulated genes in uterine leiomyoma cells contained a PR-binding site within 5 kb from their transcription start sites (TSSs), whereas 75.4% of RU486-regulated genes contained a PR-binding site farther than 50 kb from their TSSs in uterine leiomyoma cells. RU486 regulated only seven mRNAs in both cell types. Among these, adipophilin (PLIN2), a pro-differentiation gene, was induced via RU486 and PR via the same regulatory region in both cell types. Our studies have identified molecular components in a RU486/PR-controlled gene network involved in the regulation of cell growth, cell migration, and extracellular matrix function. Tissue-specific and common patterns of genome-wide PR binding and gene regulation may determine the therapeutic effects of antiprogestins in uterine fibroids and breast cancer.

  4. Genome-wide progesterone receptor binding: cell type-specific and shared mechanisms in T47D breast cancer cells and primary leiomyoma cells.

    Directory of Open Access Journals (Sweden)

    Ping Yin

    Full Text Available Progesterone, via its nuclear receptor (PR, exerts an overall tumorigenic effect on both uterine fibroid (leiomyoma and breast cancer tissues, whereas the antiprogestin RU486 inhibits growth of these tissues through an unknown mechanism. Here, we determined the interaction between common or cell-specific genome-wide binding sites of PR and mRNA expression in RU486-treated uterine leiomyoma and breast cancer cells.ChIP-sequencing revealed 31,457 and 7,034 PR-binding sites in breast cancer and uterine leiomyoma cells, respectively; 1,035 sites overlapped in both cell types. Based on the chromatin-PR interaction in both cell types, we statistically refined the consensus progesterone response element to G•ACA• • •TGT•C. We identified two striking differences between uterine leiomyoma and breast cancer cells. First, the cis-regulatory elements for HSF, TEF-1, and C/EBPα and β were statistically enriched at genomic RU486/PR-targets in uterine leiomyoma, whereas E2F, FOXO1, FOXA1, and FOXF sites were preferentially enriched in breast cancer cells. Second, 51.5% of RU486-regulated genes in breast cancer cells but only 6.6% of RU486-regulated genes in uterine leiomyoma cells contained a PR-binding site within 5 kb from their transcription start sites (TSSs, whereas 75.4% of RU486-regulated genes contained a PR-binding site farther than 50 kb from their TSSs in uterine leiomyoma cells. RU486 regulated only seven mRNAs in both cell types. Among these, adipophilin (PLIN2, a pro-differentiation gene, was induced via RU486 and PR via the same regulatory region in both cell types.Our studies have identified molecular components in a RU486/PR-controlled gene network involved in the regulation of cell growth, cell migration, and extracellular matrix function. Tissue-specific and common patterns of genome-wide PR binding and gene regulation may determine the therapeutic effects of antiprogestins in uterine fibroids and breast cancer.

  5. Proliferation and ovarian hormone signaling are impaired in normal breast tissues from women with BRCA1 mutations: benefit of a progesterone receptor modulator treatment as a breast cancer preventive strategy in women with inherited BRCA1 mutations

    Science.gov (United States)

    Communal, Laudine; Courtin, Aurélie; Mourra, Najat; Lahlou, Najiba; Le Guillou, Morwenna; de Jotemps, Muriel Perrault; Chauvet, Marie-Pierre; Chaouat, Marc; Pujol, Pascal; Feunteun, Jean; Delaloge, Suzette; Forgez, Patricia; Gompel, Anne

    2016-01-01

    Women with inherited BRCA1 mutations have an elevated risk (40-80%) for developing breast and ovarian cancers. Reproductive history has been reported to alter this risk, suggesting a relationship between ovarian hormone signaling and BRCA1-related tumor development. BRCA1 interactions with estrogen receptor (ER) and progesterone receptor (PR) signaling were previously described in human breast cancer cell lines and mouse models. However, few studies have examined the effect of ovarian hormone regulation in normal human breast tissues bearing a heterozygous BRCA1 mutation. This study compares the proliferation level (Ki67) and the expression of ER, PR, and of the PR target gene, fatty acid synthase (FASN), in histologically normal breast tissues from women with BRCA1 mutations (BRCA1+/mut, n=23) or without BRCA1 mutations (BRCA1+/+, n=28). BRCA1+/mut tissues showed an increased proliferation and impaired hormone receptor expression with a marked loss of the PR isoform, PR-B. Responses to estradiol and progesterone treatments in BRCA1+/mut and BRCA1+/+ breast tissues were studied in a mouse xenograft model, and showed that PR and FASN expression were deregulated in BRCA1+/mut breast tissues. Progesterone added to estradiol treatment increased the proliferation in a subset of BRCA1+/mut breast tissues. The PR inhibitor, ulipristal acetate (UPA), was able to reverse this aberrant progesterone-induced proliferation. This study suggests that a subset of women with BRCA1 mutations could be candidates for a UPA treatment as a preventive breast cancer strategy. PMID:27246982

  6. Plasma progesterone levels in progesterone treated cows

    International Nuclear Information System (INIS)

    Grosskopf, J.F.W.; Van Niekerk, C.H.; Morgenthal, J.C.

    1979-01-01

    A technique for the radioimmunoassay of progesterone in plasma is described. In one trial the oestrous cycles of four cycling cows and in another trial of one non-cycling cow and two cycling heifers were synchronized by the administration of progesterone. Each female received either 50 mg or 0,1 mg/kg of progesterone intramuscularly on alternate days in two courses of four and six injections respectively. Blood samples of the animals were collected either daily or two-daily before, over the entire period of treatment and for eight days after the last progesterone injection. The results of the progesterone assays are represented graphically for each individual cow or heifer. The plasma progesterone levels during treatment were maintained reasonably well at levels corresponding to those normally encountered during the luteal phase of the cycle. The progesterone levels, however, did not drop as rapidly as desired after the last injection but might have been influenced by a residual corpus luteum from a previous ovulation

  7. The Motion of a Single Molecule, the Lambda-Receptor, in the Bacterial Outer Membrane

    DEFF Research Database (Denmark)

    Oddershede, Lene; Dreyer, Jakob Kisbye; Grego, Sonia

    2002-01-01

    Using optical tweezers and single particle tracking, we have revealed the motion of a single protein, the lambda-receptor, in the outer membrane of living Escherichia coli bacteria. We genetically modified the lambda-receptor placing a biotin on an extracellular site of the receptor in vivo...

  8. hCG activates Epac-Erk1/2 signaling regulating Progesterone Receptor expression and function in human endometrial stromal cells.

    Science.gov (United States)

    Tapia-Pizarro, Alejandro; Archiles, Sebastián; Argandoña, Felipe; Valencia, Cecilia; Zavaleta, Keyla; Cecilia Johnson, M; González-Ramos, Reinaldo; Devoto, Luigi

    2017-06-01

    How does hCG signal in human endometrial stromal cells (ESCs) and what is its role in regulating ESC function? hCG signaling in ESCs activates the extracellular signal-regulated protein kinases 1 and 2 (Erk1/2) pathway through exchange protein activated by cyclic AMP (cAMP) (Epac) and transiently increases progesterone receptor (PR) transcript and protein expression and its transcriptional function. hCG is one of the earliest embryo-derived secreted signals in the endometrium, which abundantly expresses LH/hCG receptors. hCG signals through cAMP/protein kinase A (PKA) in gonadal cells, but in endometrial epithelial cells, hCG induces Erk1/2 activation independent of the cAMP/PKA pathway. Few data exist concerning the signal transduction pathways triggered by hCG in ESCs and their role in regulation of ESC function. This is an in vitro study comprising patients undergoing benign gynecological surgery (n = 46). Endometrial samples were collected from normal cycling women during the mid-secretory phase for ESCs isolation. The study conducted in an academic research laboratory within a tertiary-care hospital. The activation of the Erk1/2 signal transduction pathway elicited by hCG was evaluated in ESC. Signaling pathway inhibitors were used to examine the roles of PKA, PI3K, PKC, adenylyl cyclase and Epac on the hCG-stimulated up-regulation of phospho-Erk1/2 (pErk1/2). Erk1/2 phosphorylation was determined by immunoblot. siRNA targeting Epac was used to investigate the molecular mechanisms. To assess the role of Erk1/2 signaling induced by hCG on ESC function, gene expression regulation was examined by immunofluorescence and real-time quantitative PCR. The role of PR on the regulation of transcript levels was studied using progesterone and the PR antagonist RU486. All experiments were conducted using at least three different cell culture preparations in triplicate. Addition of hCG to ESCs in vitro induced the phosphorylation of Erk1/2 through cAMP accumulation. Such

  9. Synergistic effects of parabens on the induction of calbindin-D(9k) gene expression act via a progesterone receptor-mediated pathway in GH3 cells.

    Science.gov (United States)

    Yang, H; Nguyen, T-T; An, B-S; Choi, K-C; Jeung, Eui-Bae

    2012-02-01

    Although the endocrine-disrupting bioactivity of parabens is weakly estrogenic (parabens are xenoestrogens), their combined synergistic effect is unknown. The aim of this study was to investigate the effects of methyl paraben (MP), ethyl paraben (EP), propyl paraben (PP), isopropyl paraben (IPP), butyl paraben (BP), and isobutyl paraben (IBP), either alone or in combination (MP + EP + PP + BP; PP + IPP; and BP + IBP) on the induction of the estrogenic biomarker gene, calbindin-D(9k) (CaBP-9k), in rat pituitary lactosomatotrophic GH3 cells. The expression of CaBP-9k mRNA and protein was analyzed using real-time PCR and Western blot analysis, respectively. After 24 h of treatment, a significant increase in CaBP-9k expression was observed. This was dependent upon the length of the paraben alkyl chains (shortest in MP and longest in IBP). Interestingly, the synergistic effects of these paraben combinations were observed at a dose (10(-5) M) of these parabens, which induced the highest expression of CaBP-9k mRNA and protein. To investigate the involvement of estrogen receptors (ERs) and progesterone receptors (PRs), through which parabens exert their effects, the expression levels of ERα and PR-B were also examined. The expression of ERα mRNA and protein fluctuated after paraben treatment in GH3 cells, which was not significant. However, the expression level of ERα gene was induced when cotreated with 17β-estradiol (E2) and ICI 182, 780 (estrogen receptor antagonist). The different combinations of parabens induced the expression of the PR-B gene, which was abolished by cotreatment with ICI 182,780. The expression patterns of CaBP-9k and PR-B genes appeared to be similar in response to paraben treatments. This implied that CaBP-9k expression in GH3 cells may be induced by parabens via a PR-mediated pathway. Taken together, these results suggest that exposure to multiple parabens at low concentrations may increase their synergistic estrogenic activities in GH3 cells

  10. A comparison of survival outcomes and side effects of toremifene or tamoxifen therapy in premenopausal estrogen and progesterone receptor positive breast cancer patients: a retrospective cohort study

    International Nuclear Information System (INIS)

    Gu, Ran; Long, Meijun; Chen, Kai; Chen, Lili; Xiao, Qiaozhen; Wu, Mei; Song, Erwei; Su, Fengxi; Jia, Weijuan; Zeng, Yunjie; Rao, Nanyan; Hu, Yue; Li, Shunrong; Wu, Jiannan; Jin, Liang; Chen, Lijuan

    2012-01-01

    In premenopausal women, endocrine adjuvant therapy for breast cancer primarily consists of tamoxifen alone or with ovarian suppressive strategies. Toremifene is a chlorinated derivative of tamoxifen, but with a superior risk-benefit profile. In this retrospective study, we sought to establish the role of toremifene as an endocrine therapy for premenopausal patients with estrogen and/or progesterone receptor positive breast cancer besides tamoxifen. Patients with early invasive breast cancer were selected from the breast tumor registries at the Sun Yat-Sen Memorial Hospital (China). Premenopausal patients with endocrine responsive breast cancer who underwent standard therapy and adjuvant therapy with toremifene or tamoxifen were considered eligible. Patients with breast sarcoma, carcinosarcoma, concurrent contralateral primary breast cancer, or with distant metastases at diagnosis, or those who had not undergone surgery and endocrine therapy were ineligible. Overall survival and recurrence-free survival were the primary outcomes measured. Toxicity data was also collected and compared between the two groups. Of the 810 patients reviewed, 452 patients were analyzed in the study: 240 received tamoxifen and 212 received toremifene. The median and mean follow up times were 50.8 and 57.3 months, respectively. Toremifene and tamoxifen yielded similar overall survival values, with 5-year overall survival rates of 100% and 98.4%, respectively (p = 0.087). However, recurrence-free survival was significantly better in the toremifene group than in the tamoxifen group (p = 0.022). Multivariate analysis showed that recurrence-free survival improved independently with toremifene (HR = 0.385, 95% CI = 0.154-0.961; p = 0.041). Toxicity was similar in the two treatment groups with no women experiencing severe complications, other than hot flashes, which was more frequent in the toremifene patients (p = 0.049). No patients developed endometrial cancer. Toremifene may be a valid and

  11. Immunohistochemical localization of 3β-Hydroxysteroid dehydrogenase and progesterone receptors in the ovary and placenta during gestation of the placentotrophic lizard Mabuya sp (Squamata: Scincidae).

    Science.gov (United States)

    Duarte-Méndez, Melissa; Quintero-Silva, Jennifer; Ramírez-Pinilla, Martha Patricia

    2018-02-27

    In squamates, progesterone (P) plays a key role in the inhibition of uterine mobility during egg retention in oviparous species, and during gestation in viviparous species. The corpus luteum (CL) is the main organ responsible for the production of P; however, in some species, the CL degenerates early and the P needed for gestation maintenance should be produced in other tissues. Mabuya sp (Scincidae) is a viviparous lizard with a prolonged gestation, it produces microlecithal eggs and, consequently, has an obligate placentotrophy related with a highly complex placenta. Its CL degenerates at early stages of gestation and therefore, other sources of P should exist. The aim of this study was to determine and localize by immunohistochemistry the production of P by detection of the enzyme 3β-Hydroxysteroid dehydrogenase (3β-HSD) and P receptors (PR) during gestation in the ovary and placenta of Mabuya sp. Positive and negative control sections were used. The ovary of this species localizes 3β-HSD and PR in the same tissues. The CL of the ovaries of females at early stages of gestation were positive for both molecules, whereas they did not localize from mid gestation to the end of pregnancy. Previtellogenic and vitellogenic follicles labelled for both molecules in the follicular epithelium and thecae. The placenta of Mabuya sp. demonstrated the potential for P production from mid gestation to the end of gestation in the uterine and chorionic tissues. PR were located in the uterine tissues throughout gestation, with a decrease towards its completion. Western blot analysis confirmed the presence of 3β-HSD mainly in the ovary of early pregnant females and in the placental tissues at mid gestation stages. Therefore, the chorioallantoic placenta of Mabuya sp. has an endocrine function producing the P needed for gestation and replacing the CL from mid gestation to the end of pregnancy. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Effect of metformin on estrogen and progesterone receptor-positive (MCF-7) and triple-negative (MDA-MB-231) breast cancer cells.

    Science.gov (United States)

    Amaral, Inês; Silva, Cláudia; Correia-Branco, Ana; Martel, Fátima

    2018-03-15

    This work aimed to investigate the effect of metformin on cellular glucose uptake and metabolism by breast cancer cells, as a mechanism contributing to its anticancer properties. Estrogen and progesterone receptor-positive (MCF-7) and triple-negative (MDA-MB-231) breast cancer cell lines were used as in vitro models of breast cancer. Short-term (26 min) exposure of MCF-7 and MDA-MB-231 cells to metformin inhibited uptake of 3 H-deoxy-D-glucose ( 3 H-DG). In contrast, long-term (24 h) exposure to metformin (5 μM-1 mM) concentration-dependently increased 3 H-DG uptake in both cell lines. This effect was associated with an increase in lactate production but was not associated with changes in GLUT1 mRNA expression. Long-term exposure of MCF-7 and MDA-MB-231 cells to metformin (5 μM-1 mM) concentration-dependently reduced cell viability and culture mass and slightly increased cell proliferation rates. Combination of metformin (1 mM) with the facilitative glucose transporter (GLUT) inhibitor kaempferol (30 μM) did not change the effect of metformin on culture growth. In conclusion, short-term exposure to metformin reduces cellular glucose uptake, probably by direct inhibition of GLUT1. However, after long-term exposure to metformin, cellular uptake of glucose is significantly increased, not associated to changes in GLUT1 transcription rates. We suggest that, in the long-term, metformin induces a compensatory increase in glucose uptake in response to cellular energy depletion resulting from its inhibitory effect on mitochondrial oxidative phosphorylation machinery. Metformin-induced dependence of breast cancer cells on glycolytic pathway, associated with an anticarcinogenic effect of the drug, provides a biochemical basis for the design of new therapeutic strategies. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  13. On the use of cells or membranes for receptor binding: growth hormone secretagogues.

    Science.gov (United States)

    Pinyot, A; Nikolovski, Z; Bosch, J; Segura, J; Gutiérrez-Gallego, R

    2010-04-15

    Receptor binding techniques have been widely used in different biochemical applications, with isolated membranes being the most used receptor preparation in this type of assays. In this study, intact cells were compared with isolated membranes as receptor support for radioligand receptor binding assay. The growth hormone secretagogue receptor 1a (GHSR-1a) expressed in human embryonic kidney 293 (HEK293) cells was used as a model of G-protein-coupled receptors. Differences between using intact cells in suspension and using isolated membranes were evaluated for different aspects of the receptor binding assay: total binding variations while both receptor preparations remain on ice, modifications in incubation conditions, saturation, and competition using different agonists. Intact cells are more prone to variability. Although under optimized settings both preparations were equivalent, the K(d) value for intact cells was three times higher than that using isolated membranes. However, no significant differences were observed in competition assays obtaining practically identical K(i) values for all ligands tested. For the GHSR-1a, isolated membranes are the better choice if particular incubation conditions are required (less variability), whereas intact cells yield easy, fast, and physiological conditions for receptor binding assays. Copyright 2010 Elsevier Inc. All rights reserved.

  14. Nuclear detection of Y-box protein-1 (YB-1) closely associates with progesterone receptor negativity and is a strong adverse survival factor in human breast cancer

    International Nuclear Information System (INIS)

    Dahl, Edgar; Dunn, Sandra E; Mertens, Peter R; En-Nia, Abdelaziz; Wiesmann, Frank; Krings, Renate; Djudjaj, Sonja; Breuer, Elisabeth; Fuchs, Thomas; Wild, Peter J; Hartmann, Arndt

    2009-01-01

    Y-box binding protein-1 (YB-1) is the prototypic member of the cold shock protein family that fulfills numerous cellular functions. In the nucleus YB-1 protein orchestrates transcription of proliferation-related genes, whereas in the cytoplasm it associates with mRNA and directs translation. In human tumor entities, such as breast, lung and prostate cancer, cellular YB-1 expression indicates poor clinical outcome, suggesting that YB-1 is an attractive marker to predict patients' prognosis and, potentially, is suitable to individualize treatment protocols. Given these predictive qualities of YB-1 detection we sought to establish a highly specific monoclonal antibody (Mab) for diagnostic testing and its characterization towards outcome prediction (relapse-free and overall survival). Hybridoma cell generation was carried out with recombinant YB-1 protein as immunogen and Mab characterization was performed using immunoblotting and ELISA with recombinant and tagged YB-1 proteins, as well as immunohistochemistry of healthy and breast cancer specimens. Breast tumor tissue array staining results were analyzed for correlations with receptor expression and outcome parameters. YB-1-specific Mab F-E2G5 associates with conformational binding epitopes mapping to two domains within the N-terminal half of the protein and detects nuclear YB-1 protein by immunohistochemistry in paraffin-embedded breast cancer tissues. Prognostic evaluation of Mab F-E2G5 was performed by immunohistochemistry of a human breast cancer tissue microarray comprising 179 invasive breast cancers, 8 ductal carcinoma in situ and 37 normal breast tissue samples. Nuclear YB-1 detection in human breast cancer cells was associated with poor overall survival (p = 0.0046). We observed a close correlation between nuclear YB-1 detection and absence of progesterone receptor expression (p = 0.002), indicating that nuclear YB-1 detection marks a specific subgroup of breast cancer. Likely due to limitation of sample

  15. Nuclear detection of Y-box protein-1 (YB-1 closely associates with progesterone receptor negativity and is a strong adverse survival factor in human breast cancer

    Directory of Open Access Journals (Sweden)

    Wild Peter J

    2009-11-01

    Full Text Available Abstract Background Y-box binding protein-1 (YB-1 is the prototypic member of the cold shock protein family that fulfills numerous cellular functions. In the nucleus YB-1 protein orchestrates transcription of proliferation-related genes, whereas in the cytoplasm it associates with mRNA and directs translation. In human tumor entities, such as breast, lung and prostate cancer, cellular YB-1 expression indicates poor clinical outcome, suggesting that YB-1 is an attractive marker to predict patients' prognosis and, potentially, is suitable to individualize treatment protocols. Given these predictive qualities of YB-1 detection we sought to establish a highly specific monoclonal antibody (Mab for diagnostic testing and its characterization towards outcome prediction (relapse-free and overall survival. Methods Hybridoma cell generation was carried out with recombinant YB-1 protein as immunogen and Mab characterization was performed using immunoblotting and ELISA with recombinant and tagged YB-1 proteins, as well as immunohistochemistry of healthy and breast cancer specimens. Breast tumor tissue array staining results were analyzed for correlations with receptor expression and outcome parameters. Results YB-1-specific Mab F-E2G5 associates with conformational binding epitopes mapping to two domains within the N-terminal half of the protein and detects nuclear YB-1 protein by immunohistochemistry in paraffin-embedded breast cancer tissues. Prognostic evaluation of Mab F-E2G5 was performed by immunohistochemistry of a human breast cancer tissue microarray comprising 179 invasive breast cancers, 8 ductal carcinoma in situ and 37 normal breast tissue samples. Nuclear YB-1 detection in human breast cancer cells was associated with poor overall survival (p = 0.0046. We observed a close correlation between nuclear YB-1 detection and absence of progesterone receptor expression (p = 0.002, indicating that nuclear YB-1 detection marks a specific subgroup of

  16. Binding of canonical Wnt ligands to their receptor complexes occurs in ordered plasma membrane environments.

    Science.gov (United States)

    Sezgin, Erdinc; Azbazdar, Yagmur; Ng, Xue W; Teh, Cathleen; Simons, Kai; Weidinger, Gilbert; Wohland, Thorsten; Eggeling, Christian; Ozhan, Gunes

    2017-08-01

    While the cytosolic events of Wnt/β-catenin signaling (canonical Wnt signaling) pathway have been widely studied, only little is known about the molecular mechanisms involved in Wnt binding to its receptors at the plasma membrane. Here, we reveal the influence of the immediate plasma membrane environment on the canonical Wnt-receptor interaction. While the receptors are distributed both in ordered and disordered environments, Wnt binding to its receptors selectively occurs in more ordered membrane environments which appear to cointernalize with the Wnt-receptor complex. Moreover, Wnt/β-catenin signaling is significantly reduced when the membrane order is disturbed by specific inhibitors of certain lipids that prefer to localize at the ordered environments. Similarly, a reduction in Wnt signaling activity is observed in Niemann-Pick Type C disease cells where trafficking of ordered membrane lipid components to the plasma membrane is genetically impaired. We thus conclude that ordered plasma membrane environments are essential for binding of canonical Wnts to their receptor complexes and downstream signaling activity. © 2017 The Authors. The FEBS Journal published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.

  17. Characterization of cholecystokinin receptors on guinea pig gastric chief cell membranes

    International Nuclear Information System (INIS)

    Matozaki, T.; Sakamoto, C.; Nagao, M.; Nishisaki, H.; Konda, Y.; Nakano, O.; Matsuda, K.; Wada, K.; Suzuki, T.; Kasuga, M.

    1991-01-01

    The binding of cholecystokinin (CCK) to its receptors on guinea pig gastric chief cell membranes were characterized by the use of 125 I-CCK-octapeptide (CCK8). At 30 degrees C optimal binding was obtained at acidic pH in the presence of Mg2+, while Na+ reduced the binding. In contrast to reports on pancreatic and brain CCK receptors, scatchard analysis of CCK binding to chief cell membranes revealed two classes of binding sites. Whereas, in the presence of a non-hydrolyzable GTP analog, GTP gamma S, only a low affinity site of CCK binding was observed. Chief cell receptors recognized CCK analogs, with an order of potency of: CCK8 greater than gastrin-I greater than CCK4. Although all CCK receptor antagonists tested (dibutyryl cyclic GMP, L-364718 and CR1409) inhibited labeled CCK binding to chief cell membranes, the relative potencies of these antagonists in terms of inhibiting labeled CCK binding were different from those observed in either pancreatic membranes or brain membranes. The results indicate, therefore, that on gastric chief cell membranes there exist specific CCK receptors, which are coupled to G protein. Furthermore, chief cell CCK receptors may be distinct from pancreatic or brain type CCK receptors

  18. Distribution of IGF receptors in the plasma membrane of proximal tubular cells

    International Nuclear Information System (INIS)

    Hammerman, M.R.; Rogers, S.

    1987-01-01

    To characterize the distribution of receptors for insulin-like growth factors I and II (IGF I and II) in the plasma membrane of the renal proximal tubular cell, the authors measured binding of 125 I-labeled IGF I and 125 I-labeled IGF II to proximal tubular basolateral and brush-border membranes and characterized IGF I-stimulated phosphorylation of detergent-solubilized membranes. 125 I-IGF bound primarily to a 135,000 relative molecular weight (M r ) protein and IGF II to a 260,000 M r protein in isolated membranes. Binding of 125 I-IGF I was severalfold greater in basolateral than in brush-border membranes. IGF I-stimulated phosphorylation of the 92,000 M r β-subunit of its receptors could be demonstrated only in basolateral membranes. These findings are consistent with an asymmetrical distribution of receptors for IGF I in the plasma membrane of the renal proximal tubular cell, localization being primary on the basolateral side. In contrast, binding of 125 I-IGF II to isolated basolateral and brush-border membranes was equivalent, suggesting that receptors for this peptide are distributed more symmetrically in the plasma membrane. The findings suggest that the action of IGF I in proximal tubule are mediated via interaction of circulating peptide with specific receptors in the basolateral membrane. However, the findings established the potential for actions of IGF II to be exerted in proximal tubule via interaction with both basolateral and/or brush-border membrane receptors

  19. Comparison of solubilized and purified plasma membrane and nuclear insulin receptors

    International Nuclear Information System (INIS)

    Wong, K.Y.; Hawley, D.; Vigneri, R.; Goldfine, I.D.

    1988-01-01

    Prior studies have detected biochemical and immunological differences between insulin receptors in plasma membranes and isolated nuclei. To further investigate these receptors, they were solubilized in Triton X-100 partially purified by wheat germ agglutinin-agarose chromatography. In these preparations, the nuclear and plasma membrane receptors had very similar pH optima (pH 8.0) and reactivities to a group of polyclonal antireceptor antibodies. Further, both membrane preparations had identical binding activities when labeled insulin was competed for by unlabeled insulin (50% inhibition at 800 pM). Next, nuclear and plasma membranes were solubilized and purified to homogeneity by wheat germ agglutinin-agarose and insulin-agarose chromatography. In both receptors, labeled insulin was covalently cross-linked to a protein of 130 kilodaltons representing the insulin receptor α subunit. When preparations of both receptors were incubated with insulin and then adenosine 5'-[γ- 32 P]triphosphate, a protein of 95 kilodaltons representing the insulin receptor β subunit was phosphorylated in a dose-dependent manner. These studies indicate, therefore, that solubilized plasma membrane and nuclear insulin receptors have similar structures and biochemical properties, and they suggest that they are the same (or very similar) proteins

  20. Progesterone resistance in endometriosis: origins, consequences and interventions.

    Science.gov (United States)

    Patel, Bansari G; Rudnicki, Martin; Yu, Jie; Shu, Yimin; Taylor, Robert N

    2017-06-01

    Endometriosis is a common cause of pelvic pain and affects up to 10% of women of reproductive age. Aberrant progesterone signaling in the endometrium plays a significant role in impaired decidualization and establishment of ectopic endometrial implants. Eutopic endometrial cells from women with endometriosis fail to downregulate genes needed for decidualization, such as those involved in cell cycle regulation, leading to unbridled proliferation. Several causes of progesterone resistance in the endometrium have been postulated, including congenital "preconditioning", whereby the in utero environment renders infants susceptible to neonatal uterine bleeding and endometriosis. Progesterone action is crucial to decreasing inflammation in the endometrium, and deviant progesterone signaling results in a proinflammatory phenotype. Conversely, chronic inflammation can induce a progesterone-resistant state. Repetitive retrograde endometrial shedding begets chronic peritoneal inflammation, which further exacerbates progesterone resistance. Genetic causes of progesterone resistance include progesterone receptor gene polymorphisms, altered microRNA expression, and epigenetic modifications to progesterone receptors and their targets. Environmental toxins such as dioxin play a possible role in the genesis of endometriosis by permitting an inflammatory milieu. A consequence of impaired progesterone action is that hormonal therapy is rendered ineffective for a subset of women with endometriosis. Synthetic progestins, such as dienogest, may overcome this phenomenon by increasing progesterone receptor expression and decreasing proinflammatory cytokines. Other modalities include high dose depot formulations of progestins, medicated intrauterine devices and the likely advent of oral GnRH antagonists. Unearthing root causes of progesterone inaction in endometriosis will aid in the development of novel therapeutics geared toward prevention and treatment. © 2017 Nordic Federation of

  1. Role of CYP27A1 in progesterone metabolism in vitro and in vivo.

    Science.gov (United States)

    Escher, Geneviève; Vögeli, Isabelle; Escher, Robert; Tuckey, Robert C; Erickson, Sandra; Krozowski, Zygmunt; Frey, Felix J

    2009-10-01

    In the kidney, progesterone is inactivated to 20alpha-dihydro-progesterone (20alpha-DH-progesterone) to protect the mineralocorticoid receptor from progesterone excess. In an attempt to clone the enzyme with 20alpha-hydroxysteroid activity using expression cloning in CHOP cells and a human kidney expression library, serendipitously cDNA encoding CYP27A1 was isolated. Overexpression of CYP27A1 in CHOP cells decreased progesterone conversion to 20alpha-DH-progesterone in a dose-dependent manner, an effect enhanced by cotransfection with adrenodoxin and adrenodoxin reductase. Incubation of CHOP cells with 27-hydroxycholesterol, a product of CYP27A1, increased the ratio of progesterone to 20alpha-DH-progesterone in a concentration-dependent manner, indicating that the effect of CYP27A1 overexpression was mediated by 27-hydroxycholesterol. To analyze whether these observations are relevant in vivo, progesterone and 20alpha-DH-progesterone were measured by gas chromatography-mass spectometry in 24-h urine of CYP27A1 gene knockout (ko) mice and their control wild-type and heterozygote littermates. In CYP27A1 ko mice, urinary progesterone concentrations were decreased, 20alpha-DH-progesterone increased, and the progesterone-to-20alpha-DH-progesterone ratio decreased threefold (P CYP27A1 modulates progesterone concentrations. The underlying mechanism is inhibition of 20alpha-hydroxysteroid dehydrogenase by 27-hydroxycholesterol.

  2. Membrane-mediated action of the endocannabinoid anandamide on membrane proteins: implications for understanding the receptor-independent mechanism

    Science.gov (United States)

    Medeiros, Djalma; Silva-Gonçalves, Laíz Da Costa; da Silva, Annielle Mendes Brito; Dos Santos Cabrera, Marcia Perez; Arcisio-Miranda, Manoel

    2017-01-01

    Endocannabinoids are amphiphilic molecules that play crucial neurophysiological functions acting as lipid messengers. Antagonists and knockdown of the classical CB1 and CB2 cannabinoid receptors do not completely abolish many endocannabinoid activities, supporting the idea of a mechanism independent of receptors whose mode of action remains unclear. Here we combine gramicidin A (gA) single channel recordings and membrane capacitance measurements to investigate the lipid bilayer-modifying activity of endocannabinoids. Single channel recordings show that the incorporation of endocannabinoids into lipid bilayers reduces the free energy necessary for gramicidin channels to transit from the monomeric to the dimeric conformation. Membrane capacitance demonstrates that the endocannabinoid anandamide has limited effects on the overall structure of the lipid bilayers. Our results associated with the theory of membrane elastic deformation reveal that the action of endocannabinoids on membrane proteins can involve local adjustments of the lipid/protein hydrophobic interface. The current findings shed new light on the receptor-independent mode of action of endocannabinoids on membrane proteins, with important implications towards their neurobiological function.

  3. Naloxone-sensitive, haloperidol-sensitive, [3H](+)SKF-10047-binding protein partially purified from rat liver and rat brain membranes: an opioid/sigma receptor?

    Science.gov (United States)

    Tsao, L I; Su, T P

    1997-02-01

    A naloxone-sensitive, haloperidol-sensitive, [3H](+)SKF-10047-binding protein was partially purified from rat liver and rat brain membranes in an affinity chromatography originally designed to purify sigma receptors. Detergent-solubilized extracts from membranes were adsorbed to Sephadex G-25 resin containing an affinity ligand for sigma receptors: N-(2- 3,4-dichlorophenyl]ethyl)-N-(6-aminohexyl)-(2-[1-pyrrolidinyl]) ethylamine (DAPE). After eluting the resin with haloperidol, a protein that bound [3H](+)SKF-10047 was detected in the eluates. However, the protein was not the sigma receptor. [3H](+)SKF-10047 binding to the protein was inhibited by the following compounds in the order of decreasing potency: (+)pentazocine > (-) pentazocine > (+/-)cyclazocine > (-)morphine > (-)naloxone > haloperidol > (+)SKF-10047 > DADLE > (-)SKF-10047. Further, the prototypic sigma receptor ligands, such as 1,3-di-o-tolylguanidine (DTG), (+)3-PPP, and progesterone, bound poorly to the protein. Tryptic digestion and heat treatment of the affinity-purified protein abolished radioligand binding. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS/PAGE) of the partially-purified protein from the liver revealed a major diffuse band with a molecular mass of 31 kDa, a polypeptide of 65 kDa, and another polypeptide of > 97 kDa. This study demonstrates the existence of a novel protein in the rat liver and rat brain which binds opioids, benzomorphans, and haloperidol with namomolar affinity. The protein resembles the opioid/sigma receptor originally proposed by Martin et al. [(1976): J. Pharmacol. Exp. Ther., 197:517-532.]. A high degree of purification of this protein has been achieved in the present study.

  4. Progesterone for premenstrual syndrome

    NARCIS (Netherlands)

    Ford, Olive; Lethaby, Anne; Roberts, Helen; Mol, Ben Willem J.

    2009-01-01

    BACKGROUND: About 5% of women experience severe symptoms called premenstrual syndrome (PMS), only in the two weeks before their menstrual periods. Treatment with progesterone may restore a deficiency, balance menstrual hormone levels or reduce effects of falling progesterone levels on the brain or

  5. Dienogest, a synthetic progestin, down-regulates expression of CYP19A1 and inflammatory and neuroangiogenesis factors through progesterone receptor isoforms A and B in endometriotic cells.

    Science.gov (United States)

    Ichioka, Masayuki; Mita, Shizuka; Shimizu, Yutaka; Imada, Kazunori; Kiyono, Tohru; Bono, Yukiko; Kyo, Satoru

    2015-03-01

    Dienogest (DNG) is a selective progesterone receptor (PR) agonist and oral administration of DNG is used for the treatment of endometriosis. DNG is considered to act on PR to down-regulate pathophysiological factors associated with endometriosis. PR exists as two major isoforms, PR-A and PR-B, and their physiological functions are mostly distinct. It was suggested that PR isoform expression patterns are altered in endometriosis, but it is unknown whether the pharmacological effects of DNG are exerted through PR-A, PR-B or both. In the present study, we investigated the pharmacological effects of DNG through these PR isoforms on the expression of CYP19A1 which encodes aromatase and inflammatory and neuroangiogenesis factors associated with the pain and progression of endometriosis. We used immortalized human endometriotic epithelial cell lines that specifically express PR-A or PR-B in a spheroid cell culture system, and treated them with DNG. We evaluated messenger RNA (mRNA) expression of CYP19A1, prostaglandin (PG)E2 synthase (cyclooxygenase (COX)-2 and microsomal PGE2 synthase (mPGES)-1), inflammatory cytokines (interleukin (IL)-6, IL-8, and monocyte chemoattractant protein (MCP)-1) and neuroangiogenesis factors (vascular endothelial growth factor (VEGF) and nerve growth factor (NGF)) using real-time polymerase chain reaction. In addition, PGE2 production was measured by enzyme immunoassay. We found that DNG down-regulated mRNA expression of CYP19A1, COX-2, mPGES-1, IL-6, IL-8, MCP-1, NGF and VEGF, and PGE2 production in human endometriotic epithelial cell lines that specifically express either PR-A or PR-B. These results demonstrate that DNG activates both PR-A and PR-B and down-regulates the expression of pathophysiological factors associated with pain and progression of endometriosis. Our results suggest that DNG exerts therapeutic efficacy against the pain and progression of endometriosis regardless of PR isoform expression patterns. Copyright © 2014

  6. A randomized study on pharmacodynamic effects of vaginal rings delivering the progesterone receptor modulator ulipristal acetate: research for a novel estrogen-free, method of contraception.

    Science.gov (United States)

    Huang, YongMei; Jensen, Jeffrey T; Brache, Vivian; Cochon, Leila; Williams, Alistair; Miranda, Maria-José; Croxatto, Horacio; Kumar, Narender; Sussman, Heather; Hoskin, Elena; Plagianos, Marlena; Roberts, Kevin; Merkatz, Ruth; Blithe, Diana; Sitruk-Ware, Regine

    2014-12-01

    To determine whether a 3-month contraceptive vaginal ring (CVR) delivering ulipristal acetate (UPA) can inhibit ovulation in 90% of cycles. This was a randomized dose-finding parallel group clinical trial. Fifty-five healthy women with normal ovulation at baseline were randomized to receive a low-dose (1500 μg/day) or a high-dose (2500 μg/day) UPA-CVR for two consecutive 12-week treatment periods, followed by a recovery cycle. A subgroup of women received levonorgestrel (LNG) 1.5 mg orally twice (at the end of both 12-week ring periods) or once (at the end of the 24-week treatment). The primary outcome was ovulation suppression assessed by transvaginal ultrasound and hormone levels. Secondary outcomes included endometrial safety and bleeding patterns. All subjects showed normal ovulation at baseline and recovery. Ovulation suppression was seen in 81.8% (95% CI: 73.3%, 88.5%) and 86.1% (95% CI: 78.1%, 92%) of treatment cycles with low and high-dose, respectively. Benign progesterone receptor modulator associated endometrial changes (PAEC) were seen during treatment; 78.8% at week 24, but resolved at recovery cycle. A few cases of heavy bleeding occurred near the end of the 24-week treatment, but a single dose of LNG every 12 weeks reduced the increase in endometrial thickness during the second treatment period and prevented excessive bleeding. The 3-month UPA-CVR may become an effective long-acting, user-controlled estrogen-free contraceptive. The greatest suppression of ovulation was seen with the 2500-μg/day ring. The 3-month CVR delivering UPA 2500 μg/day can become an effective user-controlled estrogen-free contraceptive method. Benign PAEC during treatment returns to normal after discontinuation. The prevention of occasional excessive withdrawal bleeding, either by a progestin or by using higher UPA levels to increase follicle suppression may permit prolonged treatment. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Serotonin-S2 and dopamine-D2 receptors are the same size in membranes

    International Nuclear Information System (INIS)

    Brann, M.R.

    1985-01-01

    Target size analysis was used to compare the sizes of serotonin-S2 and dopamine-D2 receptors in rat brain membranes. The sizes of these receptors were standardized by comparison with the muscarinic receptor, a receptor of known size. The number of serotonin-S2 receptors labeled with (3H)ketanserin or (3H)spiperone in frontal cortex decreased as an exponential function of radiation dose, and receptor affinity was not affected. The number of dopamine-D2 receptors labeled with (3H)spiperone in striatum also decreased as an exponential function of radiation dose, and D2 and S2 receptors were equally sensitive to radiation. In both striatum and frontal cortex, the number of muscarinic receptors labeled with (3H)QNB decreased as an exponential function of radiation dose, and were much less sensitive to radiation than S2 and D2 receptors. These data indicate that in rat brain membranes, S2 and D2 receptors are of similar size, and both molecules are much larger than the muscarinic receptor

  8. 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...... difference was observed between lymph node status and ER-beta protein expression (P = .0208). In ER-alpha-negative tumors, we detected a correlation between ER-beta protein expression and high levels of Ki-67. These data suggest that ER-beta could be a prognostic marker in human breast cancer....

  9. Progesterone resistance in endometriosis

    DEFF Research Database (Denmark)

    Patel, Bansari G; Rudnicki, Martin; Yu, Jie

    2017-01-01

    Endometriosis is a common cause of pelvic pain and affects up to 10% of women of reproductive age. Aberrant progesterone signaling in the endometrium plays a significant role in impaired decidualization and establishment of ectopic endometrial implants. Eutopic endometrial cells from women...... with endometriosis fail to downregulate genes needed for decidualization, such as those involved in cell cycle regulation, leading to unbridled proliferation. Several causes of progesterone resistance in the endometrium have been postulated, including congenital "preconditioning", whereby the in utero environment...... renders infants susceptible to neonatal uterine bleeding and endometriosis. Progesterone action is crucial to decreasing inflammation in the endometrium, and deviant progesterone signaling results in a proinflammatory phenotype. Conversely, chronic inflammation can induce a progesterone resistant state...

  10. Spectrins: a structural platform for stabilization and activation of membrane channels, receptors and transporters.

    Science.gov (United States)

    Machnicka, Beata; Czogalla, Aleksander; Hryniewicz-Jankowska, Anita; Bogusławska, Dżamila M; Grochowalska, Renata; Heger, Elżbieta; Sikorski, Aleksander F

    2014-02-01

    This review focuses on structure and functions of spectrin as a major component of the membrane skeleton. Recent advances on spectrin function as an interface for signal transduction mediation and a number of data concerning interaction of spectrin with membrane channels, adhesion molecules, receptors and transporters draw a picture of multifaceted protein. Here, we attempted to show the current depiction of multitask role of spectrin in cell physiology. This article is part of a Special Issue entitled: Reciprocal influences between cell cytoskeleton and membrane channels, receptors and transporters. Guest Editor: Jean Claude Hervé. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Progesterone Exerts a Neuromodulatory Effect on Turning Behavior of Hemiparkinsonian Male Rats: Expression of 3α-Hydroxysteroid Oxidoreductase and Allopregnanolone as Suggestive of GABAA Receptors Involvement

    Directory of Open Access Journals (Sweden)

    Roberto Yunes

    2015-01-01

    Full Text Available There is a growing amount of evidence for a neuroprotective role of progesterone and its neuroactive metabolite, allopregnanolone, in animal models of neurodegenerative diseases. By using a model of hemiparkinsonism in male rats, injection of the neurotoxic 6-OHDA in left striatum, we studied progesterone’s effects on rotational behavior induced by amphetamine or apomorphine. Also, in order to find potential explanatory mechanisms, we studied expression and activity of nigrostriatal 3α-hydroxysteroid oxidoreductase, the enzyme that catalyzes progesterone to its active metabolite allopregnanolone. Coherently, we tested allopregnanolone for a possible neuromodulatory effect on rotational behavior. Also, since allopregnanolone is known as a GABAA modulator, we finally examined the action of GABAA antagonist bicuculline. We found that progesterone, in addition to an apparent neuroprotective effect, also increased ipsilateral expression and activity of 3α-hydroxysteroid oxidoreductase. It was interesting to note that ipsilateral administration of allopregnanolone reversed a clear sign of motor neurodegeneration, that is, contralateral rotational behavior. A possible GABAA involvement modulated by allopregnanolone was shown by the blocking effect of bicuculline. Our results suggest that early administration of progesterone possibly activates genomic mechanisms that promote neuroprotection subchronically. This, in turn, could be partially mediated by fast, nongenomic, actions of allopregnanolone acting as an acute modulator of GABAergic transmission.

  12. Re-Appraisal of Estrogen Receptor Negative/Progesterone Receptor Positive (ER-/PR+) Breast Cancer Phenotype: True Subtype or Technical Artefact?

    Science.gov (United States)

    Foley, Niamh M; Coll, J M; Lowery, A J; Hynes, S O; Kerin, M J; Sheehan, M; Brodie, C; Sweeney, K J

    2017-09-11

    Expression of the ER and PR receptors is routinely quantified in breast cancer as a predictive marker of response to hormonal therapy. Accurate determination of ER and PR status is critical to the optimal selection of patients for targeted therapy. The existence of an ER-/PR+ subtype is controversial, with debate centred on whether this represents a true phenotype or a technical artefact on immunohistochemistry (IHC). The aim of this study was to investigate the true incidence and clinico-pathological features of ER-/PR+ breast cancers in a tertiary referral symptomatic breast unit. Clinico-pathological data were collected on invasive breast cancers diagnosed between 1995 and 2005. IHC for ER and PR receptors was repeated on all cases which were ER-/PR+, with the same paraffin block used for the initial diagnostic testing. Concordance between the diagnostic and repeat IHC was determined using validated testing. Complete data, including ER and PR status were available for 697 patients diagnosed during the study period. On diagnostic IHC, the immunophenotype of the breast tumours was: ER+/PR+ in 396 (57%), ER-/PR- in 157 (23%), ER+/PR- in 88 (12%) and ER-/PR+ in 56 (8.6%) patients. On repeat IHC of 48/56 ER-/PR+ tumours 45.8% were ER+/PR+, 6% were ER+/PR- and 43.7% were ER-/PR- None of the cases were confirmed to be ER-/PR+. The ER-/PR+ phenotypic breast cancer is likely to be the result of technical artefact. Prompt reassessment of patients originally assigned to this subtype who re-present with symptoms should be considered to ensure appropriate clinical management.

  13. Estrogen receptor α is involved in the induction of Calbindin-D(9k) and progesterone receptor by parabens in GH3 cells: a biomarker gene for screening xenoestrogens.

    Science.gov (United States)

    Vo, Thuy T B; Jung, Eui-Man; Choi, Kyung-Chul; Yu, Frank H; Jeung, Eui-Bae

    2011-06-01

    The effects of paraben, a xenoestrogen with known endocrine disrupting bioactivity were evaluated. We used the induction of an estrogenic biomarker gene - Calbindin-D(9k) (CaBP-9k) to investigate the xenoestrogenic activity of a panel of parabens (methyl-, ethyl-, propyl-, isopropyl-, butyl-, and isobutylparabens) in GH3 rat pituitary cancer cell line. Following 24-h treatment, a significant increase in CaBP-9k expression of transcript and protein was dependent on the concentration-treated as well as the linear length of the alkyl chain from methyl- to isobutylparabens. Interestingly, co-treatment with fulvestrant, a pure antiestrogen largely reversed the paraben-dependent induction of CaBP-9k mRNA and protein in GH3 cell line. To better understand the mechanism of CaBP-9k induction by these endocrine disrupting compounds, we measured the levels of estrogen receptor (ERα) and progesterone receptor (PR) expression following parabens exposure. Also, we monitored the transiently transfected with plasmids containing of estrogen response element (ERE) sequence into GH3. In the GH3 cells, a large increase in PR mRNA and protein was observed in a concentration-dependent manner after parabens treatment that was effectively blocked in the presence of antagonist of 17β-estradiol (fulvestrant). And, luciferase activity was expressed from the putative ERE and expression was stimulated by parabens. To confirm that ERα signaling is involved in parabens induction of CaBP-9k and PR mRNA and protein, we treated GH3 cells with an antiestrogen, fulvestrant, which blocked the paraben-induced upregulation of CaBP-9k and PR. Taken together, these results indicate that CaBP-9k and PR is induced by parabens via the ER pathway in GH3 cell line. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Segregation of receptor-ligand complexes in cell adhesion zones: Phase diagrams and role of thermal membrane roughness

    OpenAIRE

    Rozycki, Bartosz; Lipowsky, Reinhard; Weikl, Thomas R.

    2010-01-01

    The adhesion zone of immune cells, the 'immunological synapse', exhibits characteristic domains of receptor-ligand complexes. The domain formation is likely caused by a length difference of the receptor-ligand complexes, and has been investigated in experiments in which T cells adhere to supported membranes with anchored ligands. For supported membranes with two types of anchored ligands, MHCp and ICAM1, that bind to the receptors TCR and LFA1 in the cell membrane, the coexistence of domains ...

  15. Androgen Receptor Localizes to Plasma Membrane by Binding to Caveolin-1 in Mouse Sertoli Cells

    Directory of Open Access Journals (Sweden)

    Qiong Deng

    2017-01-01

    Full Text Available The nonclassical androgen signaling pathway translates signals into alterations in cellular function within minutes, and this action is proposed to be mediated by an androgen receptor (AR localized to the plasma membrane. This study was designed to determine the mechanism underlying the membrane association of androgen receptor in TM4 cells, a mouse Sertoli cell line. Western blot analysis indicated testosterone-induced AR translocation to the cell membrane. Data from coimmunoprecipitation indicated that AR is associated with caveolin-1, and testosterone enhanced this association. Knockdown of caveolin-1 by shRNA decreased the amount of AR localized to membrane fraction and prevented AR membrane trafficking after being exposed to testosterone at physiological concentration. The palmitoylation inhibitor 2-bromopalmitate decreased AR membrane localization in basal condition and completely blocked testosterone-induced AR translocation to membrane fraction. These data suggested that AR localized to membrane fraction by binding with caveolin-1 through palmitoylation of the cysteine residue. This study provided a new evidence for AR membrane localization and its application for clarifying the nonclassical signaling pathway of androgens.

  16. Non-genomic actions of aldosterone: From receptors and signals to membrane targets.

    LENUS (Irish Health Repository)

    2012-02-01

    In tissues which express the mineralocorticoid receptor (MR), aldosterone modulates the expression of membrane targets such as the subunits of the epithelial Na(+) channel, in combination with important signalling intermediates such as serum and glucocorticoid-regulated kinase-1. In addition, the rapid \\'non-genomic\\' activation of protein kinases and secondary messenger signalling cascades has also been detected in aldosterone-sensitive tissues of the nephron, distal colon and cardiovascular system. These rapid actions are variously described as being coupled to MR or to an as yet unidentified, membrane-associated aldosterone receptor. The rapidly activated signalling cascades add a level of fine-tuning to the activity of aldosterone-responsive membrane transporters and also modulate the aldosterone-induced changes in gene expression through receptor and transcription factor phosphorylation.

  17. Non-genomic actions of aldosterone: From receptors and signals to membrane targets.

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2011-07-26

    In tissues which express the mineralocorticoid receptor (MR), aldosterone modulates the expression of membrane targets such as the subunits of the epithelial Na(+) channel, in combination with important signalling intermediates such as serum and glucocorticoid-regulated kinase-1. In addition, the rapid \\'non-genomic\\' activation of protein kinases and secondary messenger signalling cascades has also been detected in aldosterone-sensitive tissues of the nephron, distal colon and cardiovascular system. These rapid actions are variously described as being coupled to MR or to an as yet unidentified, membrane-associated aldosterone receptor. The rapidly activated signalling cascades add a level of fine-tuning to the activity of aldosterone-responsive membrane transporters and also modulate the aldosterone-induced changes in gene expression through receptor and transcription factor phosphorylation.

  18. Nongenomic actions of estrogens and xenoestrogens by binding at a plasma membrane receptor unrelated to estrogen receptor α and estrogen receptor β

    Science.gov (United States)

    Nadal, Angel; Ropero, Ana B.; Laribi, Ouahiba; Maillet, Marjorie; Fuentes, Esther; Soria, Bernat

    2000-01-01

    The molecular mechanism used by environmental chemicals to exert their hormone-like actions is still only partially resolved. Although it generally is accepted that xenoestrogens act at the genomic level by binding to intracellular estrogen receptors, we have shown here that they trigger nongenomic effects in pancreatic β cells. Both xenoestrogens and the circulating hormone, 17β-estradiol, bind with high affinity to a common membrane binding site unrelated to the intracellular estrogen receptors ERα and ERβ. This binding site is shared by dopamine, epinephrine, and norepinephrine and has the pharmacological profile of the γadrenergic receptor. This study provides an outline of the membrane receptor involved in rapid xenoestrogen actions. PMID:11027358

  19. Evidence that the Arcuate Nucleus Is an Important Site of Progesterone Negative Feedback in the Ewe

    Science.gov (United States)

    Holaskova, Ida; Nestor, Casey C.; Connors, John M.; Billings, Heather J.; Valent, Miro; Lehman, Michael N.; Hileman, Stanley M.

    2011-01-01

    There is now considerable evidence that dynorphin neurons mediate the negative feedback actions of progesterone to inhibit GnRH and LH pulse frequency, but the specific neurons have yet to be identified. In ewes, dynorphin neurons in the arcuate nucleus (ARC) and preoptic area (POA) are likely candidates based on colocalization with progesterone receptors. These studies tested the hypothesis that progesterone negative feedback occurs in either the ARC or POA by determining whether microimplants of progesterone into either site would inhibit LH pulse frequency (study 1) and whether microimplants of the progesterone receptor antagonist, RU486, would disrupt the inhibitory effects of peripheral progesterone (study 2). Both studies were done in ovariectomized (OVX) and estradiol-treated OVX ewes. In study 1, no inhibitory effects of progesterone were observed during treatment in either area. In study 2, microimplants of RU486 into the ARC disrupted the negative-feedback actions of peripheral progesterone treatments on LH pulse frequency in both OVX and OVX+estradiol ewes. In contrast, microimplants of RU486 into the POA had no effect on the ability of systemic progesterone to inhibit LH pulse frequency. We thus conclude that the ARC is one important site of progesterone-negative feedback in the ewe. These data, which are the first evidence on the neural sites in which progesterone inhibits GnRH pulse frequency in any species, are consistent with the hypothesis that ARC dynorphin neurons mediate this action of progesterone. PMID:21693677

  20. Mapping receptor-ligand interactions with synthetic peptide arrays: exploring the structure and function of membrane receptors.

    Science.gov (United States)

    Volkmer, Rudolf; Kretzschmar, Ines; Tapia, Victor

    2012-04-01

    Development of synthetic peptide array technology started in the early 1990s. The technique originally developed by Ronald Frank has become a powerful tool for high throughput approaches in biology and chemistry mapping protein interaction sites. In this review we focus on peptide arrays applied to investigate receptor-ligand interactions, such as peroxisomal membrane receptor proteins, the maltose importer machinery and receptor proteins recognizing short linear motifs of their partners. We present several systematic sets of peptide arrays useful for mapping protein-protein- or receptor-ligand binding sites. Besides a more technical description of the peptide array preparation we discuss in detail the reliability and improvement of mapping protein-protein interactions by synthetic peptide arrays. At least proteomic approaches for mapping protein-protein interactions by peptide arrays are shown especially for the case of protein interaction domains. Copyright © 2011 Elsevier GmbH. All rights reserved.

  1. Allosteric activation of membrane-bound glutamate receptors using coordination chemistry within living cells

    Science.gov (United States)

    Kiyonaka, Shigeki; Kubota, Ryou; Michibata, Yukiko; Sakakura, Masayoshi; Takahashi, Hideo; Numata, Tomohiro; Inoue, Ryuji; Yuzaki, Michisuke; Hamachi, Itaru

    2016-10-01

    The controlled activation of proteins in living cells is an important goal in protein-design research, but to introduce an artificial activation switch into membrane proteins through rational design is a significant challenge because of the structural and functional complexity of such proteins. Here we report the allosteric activation of two types of membrane-bound neurotransmitter receptors, the ion-channel type and the G-protein-coupled glutamate receptors, using coordination chemistry in living cells. The high programmability of coordination chemistry enabled two His mutations, which act as an artificial allosteric site, to be semirationally incorporated in the vicinity of the ligand-binding pockets. Binding of Pd(2,2‧-bipyridine) at the allosteric site enabled the active conformations of the glutamate receptors to be stabilized. Using this approach, we were able to activate selectively a mutant glutamate receptor in live neurons, which initiated a subsequent signal-transduction pathway.

  2. Intrinsically disordered cytoplasmic domains of two cytokine receptors mediate conserved interactions with membranes

    DEFF Research Database (Denmark)

    Haxholm, Gitte Wolfsberg; Nikolajsen, Louise Fletcher; Olsen, Johan Gotthardt

    2015-01-01

    Class 1 cytokine receptors regulate essential biological processes through complex intracellular signaling networks. However, the structural platform for understanding their functions is currently incomplete as structure-function studies of the intracellular domains (ICDs) are critically lacking...... of the inner plasma membrane leaflet through conserved motifs resembling immuno T-cell receptor activation motifs(ITAMs). However, contrary to the observations made for ITAMs, lipid association of the prolactin and growth hormone receptor ICDs was shown to be unaccompanied by changes in transient secondary...... structure and independent of tyrosine phosphorylation. The data presented here provides a new structural platform for studying class 1 cytokine receptors and may implicate the membrane as an active component regulating intracellular signaling....

  3. Intracellular Ca2+ and TRPM5-mediated membrane depolarization produce ATP secretion from taste receptor cells

    Science.gov (United States)

    Huang, Yijen A; Roper, Stephen D

    2010-01-01

    ATP is a transmitter secreted from taste bud receptor (Type II) cells through ATP-permeable gap junction hemichannels most probably composed of pannexin 1. The elevation of intracellular Ca2+ and membrane depolarization are both believed to be involved in transmitter secretion from receptor cells, but their specific roles have not been fully elucidated. In the present study, we show that taste-evoked ATP secretion from mouse vallate receptor cells is evoked by the combination of intracellular Ca2+ release and membrane depolarization. Unexpectedly, ATP secretion is not blocked by tetrodotoxin, indicating that transmitter release from these cells still takes place in the absence of action potentials. Taste-evoked ATP secretion is absent in receptor cells isolated from TRPM5 knockout mice or in taste cells from wild type mice where current through TRPM5 channels has been eliminated. These findings suggest that membrane voltage initiated by TRPM5 channels is required for ATP secretion during taste reception. Nonetheless, even in the absence of TRPM5 channel activity, ATP release could be triggered by depolarizing cells with KCl. Collectively, the findings indicate that taste-evoked elevation of intracellular Ca2+ has a dual role: (1) Ca2+ opens TRPM5 channels to depolarize receptor cells and (2) Ca2+ plus membrane depolarization opens ATP-permeable gap junction hemichannels. PMID:20498227

  4. Intracellular Ca(2+) and TRPM5-mediated membrane depolarization produce ATP secretion from taste receptor cells.

    Science.gov (United States)

    Huang, Yijen A; Roper, Stephen D

    2010-07-01

    ATP is a transmitter secreted from taste bud receptor (Type II) cells through ATP-permeable gap junction hemichannels most probably composed of pannexin 1. The elevation of intracellular Ca(2+) and membrane depolarization are both believed to be involved in transmitter secretion from receptor cells, but their specific roles have not been fully elucidated. In the present study, we show that taste-evoked ATP secretion from mouse vallate receptor cells is evoked by the combination of intracellular Ca(2+) release and membrane depolarization. Unexpectedly, ATP secretion is not blocked by tetrodotoxin, indicating that transmitter release from these cells still takes place in the absence of action potentials. Taste-evoked ATP secretion is absent in receptor cells isolated from TRPM5 knockout mice or in taste cells from wild type mice where current through TRPM5 channels has been eliminated. These findings suggest that membrane voltage initiated by TRPM5 channels is required for ATP secretion during taste reception. Nonetheless, even in the absence of TRPM5 channel activity, ATP release could be triggered by depolarizing cells with KCl. Collectively, the findings indicate that taste-evoked elevation of intracellular Ca(2+) has a dual role: (1) Ca(2+) opens TRPM5 channels to depolarize receptor cells and (2) Ca(2+) plus membrane depolarization opens ATP-permeable gap junction hemichannels.

  5. Study of progesterone mechanisms in radio-induced apoptosis prevention

    International Nuclear Information System (INIS)

    Vares, G.

    2004-10-01

    The purpose of this work was to study the modulation of radiation-induced cell death of human mammary tumoral cells by progesterone. On the one hand, we observed that progesterone protects cells against radiation-induced apoptosis and increases the proportion of surviving and proliferating damaged cells. On the other hand, a transcriptome analysis was undertaken in irradiated cells treated by progesterone, using DNA micro-arrays. This let us highlight several transcriptional dis-regulations that are likely to explain the protective effect of the hormone; in particular, we showed that progesterone regulates the expression of genes implicated in apoptosis signaling by death receptors. Knowing the crucial role of hormonal control and of apoptosis regulation in breast cancer initiation, our results may help to achieve a better understanding of the implication of progesterone in mammary carcinogenesis. (author)

  6. Detecting membrane progestin receptor (mPR)-interacting ...

    African Journals Online (AJOL)

    Chemicals dissolved in coral reef seawater from Albion, Mauritius that interact with mPRs were screened during this study. The relative binding a nity of these compounds to the mPRα in vitro was evaluated using a steroid binding assay with crushed cell membranes from stably transfected cells containing the mPRα gene.

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

    Science.gov (United States)

    2002-07-01

    1986). Expression of the epider- mal growth factor receptors on human cervical , ovarian and vulvar carcinomas. Cancer Res.,46: 285-293. 9.) Coussens...neurone signaling; immune and inflammatory reactions; apoptosis Aldosterone Promotion of reabsorption of sodium and excretion of potassium in kidney

  8. Membrane cholesterol access into a G-protein-coupled receptor

    Czech Academy of Sciences Publication Activity Database

    Guixa-González, R.; Albasanz, J. L.; Rodriguez-Espigares, I.; Pastor, M.; Sanz, F.; Martí-Solano, M.; Manna, M.; Martinez-Seara, Hector; Hildebrand, P. W.; Martín, M.; Selent, J.

    2017-01-01

    Roč. 8, Feb 21 (2017), č. článku 14505. ISSN 2041-1723 Institutional support: RVO:61388963 Keywords : postmortem orbitofrontal cortex * A(2A) adenosine receptor * molecular dynamics Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 12.124, year: 2016 https://www.nature.com/articles/ncomms14505

  9. The Vasopressin Type-2 Receptor and Prostaglandin Receptors EP2 and EP4 can Increase Aquaporin-2 Plasma Membrane Targeting Through a cAMP Independent Pathway

    DEFF Research Database (Denmark)

    Olesen, Emma Tina Bisgaard; Moeller, Hanne Bjerregaard; Assentoft, Mette

    2016-01-01

    Apical membrane targeting of the collecting duct water channel aquaporin-2 (AQP2) is essential for body water balance. As this event is regulated by Gs coupled 7-transmembrane receptors such as the vasopressin type 2 receptor (V2R) and the prostanoid receptors EP2 and EP4, it is believed to be c...

  10. Effect of spatial inhomogeneities on the membrane surface on receptor dimerization and signal initiation

    Directory of Open Access Journals (Sweden)

    Romica Kerketta

    2016-08-01

    Full Text Available Important signal transduction pathways originate on the plasma membrane, where microdomains may transiently entrap diffusing receptors. This results in a non-random distribution of receptors even in the resting state, which can be visualized as clusters by high resolution imaging methods. Here, we explore how spatial in-homogeneities in the plasma membrane might influence the dimerization and phosphorylation status of ErbB2 and ErbB3, two receptor tyrosine kinases that preferentially heterodimerize and are often co-expressed in cancer. This theoretical study is based upon spatial stochastic simulations of the two-dimensional membrane landscape, where variables include differential distributions and overlap of transient confinement zones (domains for the two receptor species. The in silico model is parameterized and validated using data from single particle tracking experiments. We report key differences in signaling output based on the degree of overlap between domains and the relative retention of receptors in such domains, expressed as escape probability. Results predict that a high overlap of domains, which favors transient co-confinement of both receptor species, will enhance the rate of hetero-interactions. Where domains do not overlap, simulations confirm expectations that homo-interactions are favored. Since ErbB3 is uniquely dependent on ErbB2 interactions for activation of its catalytic activity, variations in domain overlap or escape probability markedly alter the predicted patterns and time course of ErbB3 and ErbB2 phosphorylation. Taken together, these results implicate membrane domain organization as an important modulator of signal initiation, motivating the design of novel experimental approaches to measure these important parameters across a wider range of receptor systems.

  11. SNX27 mediates retromer tubule entry and endosome-to-plasma membrane trafficking of signalling receptors.

    Science.gov (United States)

    Temkin, Paul; Lauffer, Ben; Jäger, Stefanie; Cimermancic, Peter; Krogan, Nevan J; von Zastrow, Mark

    2011-06-01

    Endocytic sorting of signalling receptors between recycling and degradative pathways is a key cellular process controlling the surface complement of receptors and, accordingly, the cell's ability to respond to specific extracellular stimuli. The β2 adrenergic receptor (β2AR) is a prototypical seven-transmembrane signalling receptor that recycles rapidly and efficiently to the plasma membrane after ligand-induced endocytosis. β2AR recycling is dependent on the receptor's carboxy-terminal PDZ ligand and Rab4. This active sorting process is required for functional resensitization of β2AR-mediated signalling. Here we show that sequence-directed sorting occurs at the level of entry into retromer tubules and that retromer tubules are associated with Rab4. Furthermore, we show that sorting nexin 27 (SNX27) serves as an essential adaptor protein linking β2ARs to the retromer tubule. SNX27 does not seem to directly interact with the retromer core complex, but does interact with the retromer-associated Wiskott-Aldrich syndrome protein and SCAR homologue (WASH) complex. The present results identify a role for retromer in endocytic trafficking of signalling receptors, in regulating a receptor-linked signalling pathway, and in mediating direct endosome-to-plasma membrane traffic.

  12. Two stage binding of glucagon to receptors in rat liver plasma membranes

    International Nuclear Information System (INIS)

    Wyborski, R.J.; Horwitz, E.M.; Gurd, R.S.

    1986-01-01

    A homogeneous class of noncooperative receptors in isolated rat hepatocytes undergoes a time- and temperature-dependent conformation change with glucagon binding. A comparable system exists in rat liver plasma membranes. Dissociation assays (30 0 C) quantify the number of receptors in each conformational state. Membranes incubated without GTP demonstrated two dissociation rates. The fraction of hormone bound to the high affinity state increases with incubation time to a limiting value. With isolated membranes and a concentration of 0.2 nM [( 125 I)Iodotyrosyl 10 ]glucagon, the fraction of the high affinity form is significantly greater than that found in isolated hepatocytes. Previous work without GTP indicated that a lack of cooperativity characterized the liver membrane system. Incubation of membranes with 0.1 mM GTP increases the K/sub D/ as determined by competition assays while the slope factor (.98 +/- 0.04) indicated noncooperativity. Furthermore, in the presence of GTP a significantly greater proportion of receptors is in the low affinity state while in the absence of GTP more are in the high affinity state. The data are consistent with a mechanism by which GTP diminishes the conversion of the low affinity state to the high affinity state

  13. Decreased endogenous progesterone and ratio of progesterone to ...

    African Journals Online (AJOL)

    Progesterone and estrogen are two steroid hormones whose exposure may decrease the risk and delay the onset of ischemic stroke. The main objective of this study was to determine the plasma level of progesterone, estrogen and ratio of progesterone/estrogen in ischemic stroke patients. The plasma levels of ...

  14. Multivalent ligand-receptor-mediated interaction of small filled vesicles with a cellular membrane

    Science.gov (United States)

    Zhdanov, Vladimir P.

    2017-07-01

    The ligand-receptor-mediated contacts of small sub-100-nm-sized lipid vesicles (or nanoparticles) with the cellular membrane are of interest in the contexts of cell-to-cell communication, endocytosis of membrane-coated virions, and drug (RNA) delivery. In all these cases, the interior of vesicles is filled by biologically relevant content. Despite the diversity of such systems, the corresponding ligand-receptor interaction possesses universal features. One of them is that the vesicle-membrane contacts can be accompanied by the redistribution of ligands and receptors between the contact and contact-free regions. In particular, the concentrations of ligands and receptors may become appreciably higher in the contact regions and their composition may there be different compared to that in the suspended state in the solution. A statistical model presented herein describes the corresponding distribution of various ligands and receptors and allows one to calculate the related change of the free energy with variation of the vesicle-engulfment extent. The results obtained are used to clarify the necessary conditions for the vesicle-assisted pathway of drug delivery.

  15. Cross-linking of endothelin 1 and endothelin 3 to rat brain membranes: identification of the putative receptor(s).

    Science.gov (United States)

    Ambar, I; Kloog, Y; Sokolovsky, M

    1990-07-10

    Affinity-labeling experiments with 125I-endothelin derivatives using bifunctional cross-linking reagents were carried out in an attempt to identify the polypeptide component(s) of the endothelin/sarafotoxin receptors in rat brain tissues. In rat cerebellum, cortex, and caudate putamen, endothelin 1 specifically labeled a major component with a molecular mass of around 53,000. In the same tissues endothelin 3 specifically labeled, in addition to the 53,000 band, a band of molecular mass of 38,000. This result clearly indicates that in the brain the endothelin binding site resides within a polypeptide of apparent Mr = 53,000. The possible presence of receptor subtypes is discussed with reference also to the reported identification of endothelin receptors in chick cardiac membrane and in rat mesangial cells.

  16. Increased phorbol 12,13-dibutyrate (PDBu) receptor function associated with sickle red cell membrane ghosts

    International Nuclear Information System (INIS)

    Ramachandran, M.; Nair, C.N.; Abraham, E.C.

    1987-01-01

    The biological receptor for tumor-promoting phorbol esters has been identified as the Ca 2+ /phospholipid dependent enzyme, protein kinase C. In the red cell, this enzyme is mainly cytosolic but becomes translocated to the membrane if the cellular Ca 2+ is allowed to rise. Since cellular Ca 2+ in sickle red cells is high, it was reasoned that this enzyme may become more membrane-bound. In fact, the authors noticed a four-fold increase in the binding of 3 H-PDBu by membrane ghosts isolated from sickle red cells compared to normal red cells (pmoles PDBu bound/mg protein; normal = 0.3 vs sickle cell = 1.4). Attempts to assay the enzyme directly as phospholipid-activated 32 P incorporation into the acid-precipitable membrane proteins also indicated a two-fold increase in the radiolabelling of sickle cell membrane ghosts. Autophosphorylation of membrane proteins and analysis of the phosphorylation profile by SDS-PAGE and autoradiography revealed phosphorylation predominantly of bands 3, 4.1 and 4.9 which are known protein kinase C substrates for the red cell enzyme. The increased membrane-associated protein kinase C in sickle red cells may have a bearing on the altered membrane properties reported in this condition

  17. Segregation of receptor-ligand complexes in cell adhesion zones: phase diagrams and the role of thermal membrane roughness

    Science.gov (United States)

    Różycki, B.; Lipowsky, R.; Weikl, T. R.

    2010-09-01

    The adhesion zone of immune cells, the 'immunological synapse', exhibits characteristic domains of receptor-ligand complexes. The domain formation is probably caused by a length difference of the receptor-ligand complexes, and has been investigated in experiments in which T cells adhere to supported membranes with anchored ligands. For supported membranes with two types of anchored ligands, MHCp and ICAM1, which bind to the T-cell receptor (TCR) and the receptor LFA1 in the cell membrane, the coexistence of domains of the TCR-MHCp and LFA1-ICAM1 complexes in the cell adhesion zone has been observed for a wide range of ligand concentrations and affinities. For supported membranes with long and short ligands that bind to the same cell receptor CD2, in contrast, domain coexistence has been observed for a quite narrow ratio of ligand concentrations. In this paper, we determine detailed phase diagrams for cells adhering to supported membranes with a statistical-physical model of cell adhesion. We find a characteristic difference between the adhesion scenarios in which two types of ligands in a supported membrane bind (i) to the same cell receptor or (ii) to two different cell receptors, which helps us to explain the experimental observations. Our phase diagrams fully include thermal shape fluctuations of the cell membranes on nanometer scales, which lead to a critical point for the domain formation and to a cooperative binding of the receptors and ligands.

  18. Correlation of breast cancer subtypes, based on estrogen receptor, progesterone receptor, and HER2, with functional imaging parameters from {sup 68}Ga-RGD PET/CT and {sup 18}F-FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hai-Jeon [Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, The Institute of Radiation Medicine, Seoul (Korea, Republic of); Ewha Womans University School of Medicine, Department of Nuclear Medicine, Seoul (Korea, Republic of); Kang, Keon Wook; Jeong, Jae Min; Chung, June-Key [Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Biomedical Sciences, Seoul (Korea, Republic of); Seoul National University College of Medicine, The Institute of Radiation Medicine, Seoul (Korea, Republic of); Seoul National University, Cancer Research Institute, Seoul (Korea, Republic of); Chun, In Kook [Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul (Korea, Republic of); Kangwon National University Hospital, Department of Nuclear Medicine, Chuncheon, Kangwon-Do (Korea, Republic of); Cho, Nariya [Seoul National University College of Medicine, Department of Radiology, Jongno-gu, Seoul (Korea, Republic of); Im, Seock-Ah [Seoul National University College of Medicine, Department of Internal Medicine, Seoul (Korea, Republic of); Jeong, Sunjoo [Dankook University, Department of Molecular Biology, Yongin (Korea, Republic of); Lee, Song [Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, The Institute of Radiation Medicine, Seoul (Korea, Republic of); Jung, Kyeong Cheon [Seoul National University College of Medicine, Department of Pathology, Seoul (Korea, Republic of); Lee, Yun-Sang [Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul (Korea, Republic of); Lee, Dong Soo [Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, The Institute of Radiation Medicine, Seoul (Korea, Republic of); Seoul National University, Department of Molecular Medicine and Biopharmaceutical Sciences, Seoul (Korea, Republic of); Moon, Woo Kyung [Seoul National University College of Medicine, Department of Radiology, Jongno-gu, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Biomedical Sciences, Seoul (Korea, Republic of); Seoul National University College of Medicine, The Institute of Radiation Medicine, Seoul (Korea, Republic of)

    2014-08-15

    Imaging biomarkers from functional imaging modalities were assessed as potential surrogate markers of disease status. Specifically, in this prospective study, we investigated the relationships between functional imaging parameters and histological prognostic factors and breast cancer subtypes. In total, 43 patients with large or locally advanced invasive ductal carcinoma (IDC) were analyzed (47.6 ± 7.5 years old). {sup 68}Ga-Labeled arginine-glycine-aspartic acid (RGD) and {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) were performed. The maximum and average standardized uptake values (SUV{sub max} and SUV{sub avg}) from RGD PET/CT and SUV{sub max} and SUV{sub avg} from FDG PET/CT were the imaging parameters used. For histological prognostic factors, estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expression was identified using immunohistochemistry (IHC) or fluorescent in situ hybridization (FISH). Four breast cancer subtypes, based on ER/PR and HER2 expression (ER/PR+,Her2-, ER/PR+,Her2+, ER/PR-,Her2+, and ER/PR-,Her2-), were considered. Quantitative FDG PET parameters were significantly higher in the ER-negative group (15.88 ± 8.73 vs 10.48 ± 6.01, p = 0.02 for SUV{sub max}; 9.40 ± 5.19 vs 5.92 ± 4.09, p = 0.02 for SUV{sub avg}) and the PR-negative group (8.37 ± 4.94 vs 4.79 ± 3.93, p = 0.03 for SUV{sub avg}). Quantitative RGD PET parameters were significantly higher in the HER2-positive group (2.42 ± 0.59 vs 2.90 ± 0.75, p = 0.04 for SUV{sub max}; 1.60 ± 0.38 vs 1.95 ± 0.53, p = 0.04 for SUV{sub avg}) and showed a significant positive correlation with the HER2/CEP17 ratio (r = 0.38, p = 0.03 for SUV{sub max} and r = 0.46, p < 0.01 for SUV{sub avg}). FDG PET parameters showed significantly higher values in the ER/PR-,Her2- subgroup versus the ER/PR+,Her2- or ER/PR+,Her2+ subgroups, while RGD PET parameters showed significantly lower values in the ER

  19. Predominant membrane localization is an essential feature of the bacterial signal recognition particle receptor

    Directory of Open Access Journals (Sweden)

    Graumann Peter

    2009-11-01

    Full Text Available Abstract Background The signal recognition particle (SRP receptor plays a vital role in co-translational protein targeting, because it connects the soluble SRP-ribosome-nascent chain complex (SRP-RNCs to the membrane bound Sec translocon. The eukaryotic SRP receptor (SR is a heterodimeric protein complex, consisting of two unrelated GTPases. The SRβ subunit is an integral membrane protein, which tethers the SRP-interacting SRα subunit permanently to the endoplasmic reticulum membrane. The prokaryotic SR lacks the SRβ subunit and consists of only the SRα homologue FtsY. Strikingly, although FtsY requires membrane contact for functionality, cell fractionation studies have localized FtsY predominantly to the cytosolic fraction of Escherichia coli. So far, the exact function of the soluble SR in E. coli is unknown, but it has been suggested that, in contrast to eukaryotes, the prokaryotic SR might bind SRP-RNCs already in the cytosol and only then initiates membrane targeting. Results In the current study we have determined the contribution of soluble FtsY to co-translational targeting in vitro and have re-analysed the localization of FtsY in vivo by fluorescence microscopy. Our data show that FtsY can bind to SRP-ribosome nascent chains (RNCs in the absence of membranes. However, these soluble FtsY-SRP-RNC complexes are not efficiently targeted to the membrane. In contrast, we observed effective targeting of SRP-RNCs to membrane-bond FtsY. These data show that soluble FtsY does not contribute significantly to cotranslational targeting in E. coli. In agreement with this observation, our in vivo analyses of FtsY localization in bacterial cells by fluorescence microscopy revealed that the vast majority of FtsY was localized to the inner membrane and that soluble FtsY constituted only a negligible species in vivo. Conclusion The exact function of the SRP receptor (SR in bacteria has so far been enigmatic. Our data show that the bacterial SR is

  20. DMPD: CR3 (CD11b, CD18): a phagocyte and NK cell membrane receptor with multipleligand specificities and functions. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 8485905 CR3 (CD11b, CD18): a phagocyte and NK cell membrane receptor with multipleligand specificities...) (.html) (.csml) Show CR3 (CD11b, CD18): a phagocyte and NK cell membrane receptor with multipleligand specificities...d NK cell membrane receptor with multipleligand specificities and functions. Authors Ross GD, Vetvicka V. Pu

  1. Tryptic mapping and membrane topology of the benzodiazepine receptor alpha-subunit

    Energy Technology Data Exchange (ETDEWEB)

    Lentes, K.U.; Venter, J.C.

    1986-05-01

    Rat brain membrane benzodiazepine receptors (BZR) were photoaffinity labelled specifically (in presence or absence of 6 ..mu..M clonazepam) with 10 nM /sup 3/H-flunitrazepam (FNZ). Digestion of the FNZ-labelled, membrane-bound BZR with 200 ..mu..g trypsin/mg membrane protein yielded H/sub 2/O-soluble BZR-fragments of molecular mass (M/sub r/) 34, 31, 28, 24, 21, 18, 16, 12, 10 and 7kDa. Because the 34kDa-peptide is the largest fragment containing a FNZ-binding site they conclude that this represents the extracellular domain of the BZR. In the remaining pellet two labelled peptides with M/sub r/ of 44kDa and 28kDa were found that required the use of detergents for their solubilization; they therefore contain the membrane anchoring domain. Digestion of the 0.5% Na-deoxycholate solubilized, intact BZR (M/sub r/ 51kDa) resulted in the same tryptic pattern as the membrane form of the receptor plus two larger fragments of M/sub r/ 45kDa and 40kDa. Arrangement of all tryptic fragments with reference to the FNZ binding site reveals a membrane topology of the BZR alpha-subunit with 67% (34kDa) for the extracellular domain, 21% (11kDa) for the membrane anchoring domain and 12% (6kDa) for a putative cytoplasmic domain. The overlap between some of the labelled fragments suggest that the BZ binding site must be located near the membrane surface of the extracellular domain.

  2. Interaction of lectins with membrane receptors on erythrocyte surfaces.

    Science.gov (United States)

    Sung, L A; Kabat, E A; Chien, S

    1985-08-01

    The interactions of human genotype AO erythrocytes (red blood cells) (RBCs) with N-acetylgalactosamine-reactive lectins isolated from Helix pomatia (HPA) and from Dolichos biflorus (DBA) were studied. Binding curves obtained with the use of tritium-labeled lectins showed that the maximal numbers of lectin molecules capable of binding to human genotype AO RBCs were 3.8 X 10(5) and 2.7 X 10(5) molecules/RBC for HPA and DBA, respectively. The binding of one type of lectin may influence the binding of another type. HPA was found to inhibit the binding of DBA, but not vice versa. The binding of HPA was weakly inhibited by a beta-D-galactose-reactive lectin isolated from Ricinus communis (designated RCA1). Limulus polyphemus lectin (LPA), with specificity for N-acetylneuraminic acid, did not influence the binding of HPA but enhanced the binding of DBA. About 80% of LPA receptors (N-acetylneuraminic acid) were removed from RBC surfaces by neuraminidase treatment. Neuraminidase treatment of RBCs resulted in increases of binding of both HPA and DBA, but through different mechanisms. An equal number (7.6 X 10(5) of new HPA sites were generated on genotypes AO and OO RBCs by neuraminidase treatment, and these new sites accounted for the enhancement (AO cells) and appearance (OO cells) of hemagglutinability by HPA. Neuraminidase treatment did not generate new DBA sites, but increased the DBA affinity for the existing receptors; as a result, genotype AO cells increased their hemagglutinability by DBA, while OO cells remained unagglutinable. The use of RBCs of different genotypes in binding assays with 3H-labeled lectins of known specificities provides an experimental system for studying cell-cell recognition and association.

  3. The Level of NMDA Receptor in the Membrane Modulates Amyloid-β Association and Perforation.

    Science.gov (United States)

    Peters, Christian; Sepúlveda, Fernando J; Fernández-Pérez, Eduardo J; Peoples, Robert W; Aguayo, Luis G

    2016-05-06

    Alzheimer's disease is a neurodegenerative disorder that affects mostly the elderly. The main histopathological markers are the senile plaques formed by amyloid-β peptide (Aβ) aggregates that can perforate the plasma membrane of cells, increasing the intracellular calcium levels and releasing synaptic vesicles that finally lead to a delayed synaptic failure. Several membrane proteins and lipids interact with Aβ affecting its toxicity in neurons. Here, we focus on NMDA receptors (NMDARs) as proteins that could be modulating the association and neurotoxic perforation induced by Aβ on the plasma membrane. In fact, our results showed that decreasing NMDARs, using enzymatic or siRNA approaches, increased the association of Aβ to the neurons. Furthermore, overexpression of NMDARs also resulted in an enhanced association between NMDA and Aβ. Functionally, the reduction in membrane NMDARs augmented the process of membrane perforation. On the other hand, overexpressing NMDARs had a protective effect because Aβ was now unable to cause membrane perforation, suggesting a complex relationship between Aβ and NMDARs. Because previous studies have recognized that Aβ oligomers are able to increase membrane permeability and produce amyloid pores, the present study supports the conclusion that NMDARs play a critical protective role on Aβ actions in hippocampal neurons. These results could explain the lack of correlation between brain Aβ burden and clinically observed dementia.

  4. Cell Receptor-Basement Membrane Interactions in Health and Disease: a Kidney-Centric View

    Science.gov (United States)

    Borza, Corina M.; Chen, Xiwu; Zent, Roy; Pozzi, Ambra

    2016-01-01

    Cell-extracellular matrix (ECM) interactions are essential for tissue development, homeostasis, and response to injury. Basement membranes (BMs) are specialized ECMs that separate epithelial or endothelial cells from stromal components and interact with cells via cellular receptors, including integrins and discoidin domain receptors. Disruption of cell-BM interactions due to either injury or genetic defects in either the ECM components or cellular receptors often lead to irreversible tissue injury and loss of organ function. Animal models that lack specific BM components or receptors either globally or in selective tissues have been used to help with our understanding of the molecular mechanisms whereby cell-BM interactions regulate organ function in physiological and pathological conditions. We review recently published work on animal models that explore how cell-BM interactions regulate kidney homeostasis in both health and disease. PMID:26610916

  5. Sch proteins are localized on endoplasmic reticulum membranes and are redistributed after tyrosine kinase receptor activation

    DEFF Research Database (Denmark)

    Lotti, L V; Lanfrancone, L; Migliaccio, E

    1996-01-01

    The intracellular localization of Shc proteins was analyzed by immunofluorescence and immunoelectron microscopy in normal cells and cells expressing the epidermal growth factor receptor or the EGFR/erbB2 chimera. In unstimulated cells, the immunolabeling was localized in the central perinuclear...... and endocytic structures, such as coated pits and endosomes, and with the peripheral cytosol. Receptor activation in cells expressing phosphorylation-defective mutants of Shc and erbB-2 kinase showed that receptor autophosphorylation, but not Shc phosphorylation, is required for redistribution of Shc proteins....... The rough endoplasmic reticulum localization of Shc proteins in unstimulated cells and their massive recruitment to the plasma membrane, endocytic structures, and peripheral cytosol following receptor tyrosine kinase activation could account for multiple putative functions of the adaptor protein....

  6. Androgen and Progesterone Receptors Are Targets for Bisphenol A (BPA), 4-Methyl-2,4-bis-(P-Hydroxyphenyl)Pent-1-Ene--A Potent Metabolite of BPA, and 4-Tert-Octylphenol: A Computational Insight.

    Science.gov (United States)

    Rehan, Mohd; Ahmad, Ejaz; Sheikh, Ishfaq A; Abuzenadah, Adel M; Damanhouri, Ghazi A; Bajouh, Osama S; AlBasri, Samera F; Assiri, Mansour M; Beg, Mohd A

    2015-01-01

    Exposure to toxic industrial chemicals that have capacity to disrupt the endocrine system, also known as endocrine disrupting chemicals (EDCs), has been increasingly associated with reproductive problems in human population. Bisphenol A (BPA; 4,4'-(propane-2,2-diyl)diphenol) and 4-tert-octylphenol (OP; 4-(1,1,3,3-tetramethylbutyl)phenol) are among the most common environmental contaminants possessing endocrine disruption properties and are present in plastics, epoxy resins, detergents and other commercial products of common personal and industrial use. A metabolite of BPA, 4-Methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene (MBP) is about 1000 times more biologically active compared to BPA. Epidemiological, clinical, and experimental studies have shown association of BPA and OP with adverse effects on male and female reproductive system in human and animals. The endocrine disruption activity can occur through multiple pathways including binding to steroid receptors. Androgen receptor (AR) and progesterone receptor (PR) are critical for reproductive tract growth and function. Structural binding characterization of BPA, MBP, and OP with AR and PR using molecular docking simulation approaches revealed novel interactions of BPA with PR, and MBP and OP with AR and PR. For BPA, MBP, and OP, five AR interacting residues Leu-701, Leu-704, Asn-705, Met-742, and Phe-764 overlapped with those of native AR ligand testosterone, and four PR interacting residues Leu-715, Leu-718, Met-756, and Met-759 overlapped with those of PR co-complex ligand, norethindrone. For both the receptors the binding strength of MBP was maximum among the three compounds. Thus, these compounds have the potential to block or interfere in the binding of the endogenous native AR and PR ligands and, hence, resulting in dysfunction. The knowledge of the key interactions and the important amino-acid residues also allows better prediction of potential of xenobiotic molecules for disrupting AR- and PR

  7. Androgen and Progesterone Receptors Are Targets for Bisphenol A (BPA, 4-Methyl-2,4-bis-(P-HydroxyphenylPent-1-Ene--A Potent Metabolite of BPA, and 4-Tert-Octylphenol: A Computational Insight.

    Directory of Open Access Journals (Sweden)

    Mohd Rehan

    Full Text Available Exposure to toxic industrial chemicals that have capacity to disrupt the endocrine system, also known as endocrine disrupting chemicals (EDCs, has been increasingly associated with reproductive problems in human population. Bisphenol A (BPA; 4,4'-(propane-2,2-diyldiphenol and 4-tert-octylphenol (OP; 4-(1,1,3,3-tetramethylbutylphenol are among the most common environmental contaminants possessing endocrine disruption properties and are present in plastics, epoxy resins, detergents and other commercial products of common personal and industrial use. A metabolite of BPA, 4-Methyl-2,4-bis(4-hydroxyphenylpent-1-ene (MBP is about 1000 times more biologically active compared to BPA. Epidemiological, clinical, and experimental studies have shown association of BPA and OP with adverse effects on male and female reproductive system in human and animals. The endocrine disruption activity can occur through multiple pathways including binding to steroid receptors. Androgen receptor (AR and progesterone receptor (PR are critical for reproductive tract growth and function. Structural binding characterization of BPA, MBP, and OP with AR and PR using molecular docking simulation approaches revealed novel interactions of BPA with PR, and MBP and OP with AR and PR. For BPA, MBP, and OP, five AR interacting residues Leu-701, Leu-704, Asn-705, Met-742, and Phe-764 overlapped with those of native AR ligand testosterone, and four PR interacting residues Leu-715, Leu-718, Met-756, and Met-759 overlapped with those of PR co-complex ligand, norethindrone. For both the receptors the binding strength of MBP was maximum among the three compounds. Thus, these compounds have the potential to block or interfere in the binding of the endogenous native AR and PR ligands and, hence, resulting in dysfunction. The knowledge of the key interactions and the important amino-acid residues also allows better prediction of potential of xenobiotic molecules for disrupting AR- and PR

  8. Heterologous expression of a deuterated membrane-integrated receptor and partial deuteration in methylotrophic yeasts

    International Nuclear Information System (INIS)

    Massou, S.; Puech, V.; Talmont, F.; Demange, P.; Lindley, N.D.; Tropis, M.; Milon, A.

    1999-01-01

    Methylotrophic yeast has previously been shown to be an excellent system for the cost-effective production of perdeuterated biomass and for the heterologous expression of membrane receptors. A protocol for the expression of 85% deuterated, functional human μ-opiate receptor was established. For partially deuterated biomass, deuteration level and distribution were determined for fatty acids, amino acids and carbohydrates. It was shown that prior to biosynthesis of lipids and amino acids (and of carbohydrates, to a lower extent), exchange occurs between water and methanol hydrogen atoms, so that 80%-90% randomly deuterated biomass and over-expressed proteins may be obtained using only deuterated water

  9. Purity and stability of the membrane-limited glucocorticoid receptor agonist dexamethasone-BSA.

    Science.gov (United States)

    Weiss, Grant L; Rainville, Jennifer R; Zhao, Qi; Tasker, Jeffrey G

    2017-09-20

    Cellular effects of glucocorticoids can be separated into classical transcriptional regulation via activation of the canonical nuclear glucocorticoid receptor and rapid actions mediated by activation of one or more putative membrane-associated glucocorticoid receptors that regulate both transcriptional and non-transcriptional signaling. Dexamethasone-bovine serum albumin (Dex-BSA) is one of several membrane-limited steroid receptor agonists. Dex-BSA and other steroid conjugates such as corticosterone-, estradiol- and testosterone-BSA have been used to study rapid steroid effects initiated by putative membrane receptors. The purity and stability of the steroid-BSA conjugate is crucial, therefore, since any steroid that is not bound to or that dissociates from the BSA conjugate could penetrate into the intracellular compartment and confound the experiment. We used fluorine NMR to determine if free Dex could be detected in a commercially available Dex-BSA dissolved in H 2 O. Non-covalently bound Dex was detected in the Dex-BSA solution, but the level of free Dex remained constant over time and with increasing temperature, indicating that the free Dex was not a result of instability of the Dex-BSA conjugate. The free Dex was lost when the Dex-BSA was denatured and subjected to dialysis, which suggested that it was trapped in the Dex-BSA three-dimensional structure and not covalently bound to the BSA. The purified, renatured Dex-BSA retained its rapid activity, which confirmed that the observed effects of Dex-BSA are not caused by non-covalently-bound Dex. Therefore, the Dex contaminant found in the Dex-BSA solution is likely to be tightly, but non-covalently, bound to BSA, and the Dex-BSA activity remains membrane-limited. Our findings indicate that Dex-BSA remains a suitable membrane-restricted glucocorticoid receptor agonist, but suggest that denaturing purification is a useful control for the study of membrane-initiated steroid-BSA actions. Copyright © 2017

  10. Identification and characterization of insulin receptors in basolateral membranes of dog intestinal mucosa

    International Nuclear Information System (INIS)

    Gingerich, R.L.; Gilbert, W.R.; Comens, P.G.; Gavin, J.R. III

    1987-01-01

    Little is known about hormonal regulation of substrate transport and metabolism in the mucosal lining of the small intestine. Because insulin regulates these functions in other tissues by binding to its receptor, we have investigated the presence of insulin receptors in canine small intestinal mucosa with basolateral membranes (BLM) and brush border membranes (BBM) prepared by sorbitol density centrifugation. A14-[ 125 I]iodoinsulin was used to study binding and structural characteristics of specific insulin receptors in BLM. Analysis of receptors in BLM identified binding sites with high affinity (Kd 88 pM) and low capacity (0.4 pmol/mg protein) as well as with low affinity (Kd 36 nM) and high capacity (4.7 pmol/mg protein). Binding was time, temperature, and pH dependent, and 125 I-labeled insulin dissociation was enhanced in the presence of unlabeled insulin. Cross-reactivity of these receptors to proinsulin, IGF-II, and IGF-I was 4, 1.8, and less than 1%, respectively. Covalent cross-linking of labeled insulin to BLM insulin receptors with disuccinimidyl suberate revealed a single 135,000-Mr band that was completely inhibited by unlabeled insulin. There was a 16-fold greater specific binding of insulin to BLM (39.0 +/- 2.4%) than to BBM (2.5 +/- 0.6%). These results demonstrate the presence of a highly specific receptor for insulin on the vascular, but not the luminal, surface of the small intestinal mucosa in dogs, and suggest that insulin may play an important role in the regulation of gastrointestinal physiology

  11. In vitro membrane reconstitution of the T cell receptor proximal signaling network

    OpenAIRE

    Hui, Enfu; Vale, Ronald D.

    2014-01-01

    T-cell receptor (TCR) phosphorylation is controlled by a complex network that includes Lck, a Src family kinase (SFK), the tyrosine phosphatase CD45, and the Lck-inhibitory kinase Csk. How these competing phosphorylation and dephosphorylation reactions are modulated to produce T-cell triggering is not fully understood. Here we reconstituted this signaling network using purified enzymes on liposomes, recapitulating the membrane environment in which they normally interact. We demonstrate that L...

  12. Membrane-Mediated Oligomerization of G Protein Coupled Receptors and Its Implications for GPCR Function.

    Science.gov (United States)

    Gahbauer, Stefan; Böckmann, Rainer A

    2016-01-01

    The dimerization or even oligomerization of G protein coupled receptors (GPCRs) causes ongoing, controversial debates about its functional role and the coupled biophysical, biochemical or biomedical implications. A continously growing number of studies hints to a relation between oligomerization and function of GPCRs and strengthens the assumption that receptor assembly plays a key role in the regulation of protein function. Additionally, progress in the structural analysis of GPCR-G protein and GPCR-ligand interactions allows to distinguish between actively functional and non-signaling complexes. Recent findings further suggest that the surrounding membrane, i.e., its lipid composition may modulate the preferred dimerization interface and as a result the abundance of distinct dimeric conformations. In this review, the association of GPCRs and the role of the membrane in oligomerization will be discussed. An overview of the different reported oligomeric interfaces is provided and their capability for signaling discussed. The currently available data is summarized with regard to the formation of GPCR oligomers, their structures and dependency on the membrane microenvironment as well as the coupling of oligomerization to receptor function.

  13. Progress on the M-type phospholipase A2 receptor in idiopathic membranous nephropathy.

    Science.gov (United States)

    Wang, Chao; Lu, Huan; Yang, Cui; Luo, Yuezhong

    2014-01-01

    To highlight current knowledge about M-type phospholipase A2 receptor (PLA2R) which is the first human autoantigen discovered in adult idiopathic membranous nephropathy. Relevant articles published in English from 2000 to present were selected from PubMed. Searches were made using the terms "idiopathic membranous nephropathy, M-type PLA2R and podocyte." Articles studying the role of M-type PLA2R in idiopathic membranous nephropathy were reviewed. Articles focusing on the discovery, detection and clinical observation of anti-PLA2R antibodies were selected. M-type PLA2R is a member of the mannose receptor family of proteins, locating on normal human glomeruli as a transmembrane receptor. The anti-PLA2R in serum samples from MN were primarily IgG4 subclass. Technologies applied to detect anti-PLA2R autoantibody are mainly WB, IIFT, ELISA and so on. Studies from domestic and overseas have identified a strongly relationship between circulating anti-PLA2R levels and disease activity. Recent discoveries corresponding to PLA2R facilitate a better understanding on IMN pathogenesis and may provide a new tool to its diagnosis, differential diagnosis, risk evaluation, response monitoring and patient-specific treatment.

  14. Nicotinic acetylcholine receptor and the structural basis of neuromuscular transmission: insights from Torpedo postsynaptic membranes.

    Science.gov (United States)

    Unwin, Nigel

    2013-11-01

    The nicotinic acetylcholine (ACh) receptor, at the neuromuscular junction, is a neurotransmitter-gated ion channel that has been fine-tuned through evolution to transduce a chemical signal into an electrical signal with maximum efficiency and speed. It is composed from three similar and two identical polypeptide chains, arranged in a ring around a narrow membrane pore. Central to the design of this assembly is a hydrophobic gate in the pore, more than 50 Å away from sites in the extracellular domain where ACh binds. Although the molecular properties of the receptor have been explored intensively over the last few decades, only recently have structures emerged revealing its complex architecture and illuminating how ACh entering the binding sites opens the distant gate. Postsynaptic membranes isolated from the (muscle-derived) electric organ of the Torpedo ray have underpinned most of the structural studies: the membranes form tubular vesicles having receptors arranged on a regular surface lattice, which can be imaged directly in frozen physiological solutions. Advances in electron crystallographic techniques have also been important, enabling analysis of the closed- and open-channel forms of the receptor in unreacted tubes or tubes reacted briefly with ACh. The structural differences between these two forms show that all five subunits participate in a concerted conformational change communicating the effect of ACh binding to the gate, but that three of them (αγ, β and δ) play a dominant role. Flexing of oppositely facing pore-lining α-helices is the principal motion determining the closed/open state of the gate. These results together with the findings of biochemical, biophysical and other structural studies allow an integrated description of the receptor and of its mode of action at the synapse.

  15. A model for the biosynthesis and transport of plasma membrane-associated signaling receptors to the cell surface

    Directory of Open Access Journals (Sweden)

    Sorina Claudia Popescu

    2012-04-01

    Full Text Available Intracellular protein transport is emerging as critical in determining the outcome of receptor-activated signal transduction pathways. In plants, relatively little is known about the nature of the molecular components and mechanisms involved in coordinating receptor synthesis and transport to the cell surface. Recent advances in this field indicate that signaling pathways and intracellular transport machinery converge and coordinate to render receptors competent for signaling at their plasma membrane activity sites. The biogenesis and transport to the cell surface of signaling receptors appears to require both general trafficking and receptor-specific factors. Several molecular determinants, residing or associated with compartments of the secretory pathway and known to influence aspects in receptor biogenesis, are discussed and integrated into a predictive cooperative model for the functional expression of signaling receptors at the plasma membrane.

  16. Development of a competitive lateral flow immunoassay for progesterone : influence of coating conjugates and buffer components

    NARCIS (Netherlands)

    Posthuma-Trumpie, Geertruida A.; Korf, Jakob; van Amerongen, Aart

    2008-01-01

    Several aspects of the development of competitive lateral flow immunoassays (LFIAs) are described. The quantitation of progesterone is taken as an example. The LFIA format consisted of a nitrocellulose membrane spotted with various progesterone conjugates as the test line. A mixture of primary

  17. Development of a competitive lateral flow immunoassay for progesterone: influence of coating conjugates and buffer components

    NARCIS (Netherlands)

    Posthuma-Trumpie, G.A.; Korf, J.; Amerongen, van A.

    2008-01-01

    Several aspects of the development of competitive lateral flow immunoassays (LFIAs) are described. The quantitation of progesterone is taken as an example. The LFIA format consisted of a nitrocellulose membrane spotted with various progesterone conjugates as the test line. A mixture of primary

  18. Impact of size of the tumor, persistence of estrogen receptors, progesterone receptors, HER2neu receptors and Ki67 values on positivity of axillar lymph nodes at patients with early breast cancer with clinically negative axillar examination

    Directory of Open Access Journals (Sweden)

    Borislav Kondov

    2017-10-01

    Conclusion: Our study showed that the involving of the axillary lymph nodes is mainly influenced from the size of the tumor and presence of HER2neu receptors  in the univariant analysis points the important influence of positivity in the axillary lymph nodes but only size of the tumor in multivariate regressive analysis.

  19. Membrane mineralocorticoid but not glucocorticoid receptors of the dorsal hippocampus mediate the rapid effects of corticosterone on memory retrieval

    OpenAIRE

    Dorey, Rodolphe; Piérard, Christophe; Shinkaruk, Svitlana; Tronche, Christophe; Chauveau, Frédéric; Baudonnat, Matthieu; Beracochea, Daniel

    2011-01-01

    Abstract This study was aimed at determining the type of the glucocorticoid membrane receptors (mineralo or glucocorticoid receptors, MR or GR) in the dorsal hippocampus (dHPC) involved in the rapid effects of corticosterone or stress on memory retrieval. For that purpose, we synthesized Cort-3CMO-BSA conjugate (a high MW complex which cannot cross the cell membrane) totally devoid of free corticosterone, stable in physiological conditions. In a first experiment, we evidenced that ...

  20. Ligand-induced type II interleukin-4 receptor dimers are sustained by rapid re-association within plasma membrane microcompartments

    Science.gov (United States)

    Richter, David; Moraga, Ignacio; Winkelmann, Hauke; Birkholz, Oliver; Wilmes, Stephan; Schulte, Markos; Kraich, Michael; Kenneweg, Hella; Beutel, Oliver; Selenschik, Philipp; Paterok, Dirk; Gavutis, Martynas; Schmidt, Thomas; Garcia, K. Christopher; Müller, Thomas D.; Piehler, Jacob

    2017-07-01

    The spatiotemporal organization of cytokine receptors in the plasma membrane is still debated with models ranging from ligand-independent receptor pre-dimerization to ligand-induced receptor dimerization occurring only after receptor uptake into endosomes. Here, we explore the molecular and cellular determinants governing the assembly of the type II interleukin-4 receptor, taking advantage of various agonists binding the receptor subunits with different affinities and rate constants. Quantitative kinetic studies using artificial membranes confirm that receptor dimerization is governed by the two-dimensional ligand-receptor interactions and identify a critical role of the transmembrane domain in receptor dimerization. Single molecule localization microscopy at physiological cell surface expression levels, however, reveals efficient ligand-induced receptor dimerization by all ligands, largely independent of receptor binding affinities, in line with the similar STAT6 activation potencies observed for all IL-4 variants. Detailed spatiotemporal analyses suggest that kinetic trapping of receptor dimers in actin-dependent microcompartments sustains robust receptor dimerization and signalling.

  1. Plasma membrane calcium ATPases are important components of receptor-mediated signaling in plant immune responses and development.

    NARCIS (Netherlands)

    Frei dit Frey, N.; Mbengue, M.; Kwaaitaal, M.A.C.J.; Nitsch, L.M.C.; Altenbach, D.; Häweker, H.; Lozano-Duran, R.; Njo, M.F.; Beeckman, T.; Huettel, B.; Borst, J.W.; Panstruga, R.; Robatzek, S.

    2012-01-01

    Plasma membrane-resident receptor kinases (RKs) initiate signaling pathways important for plant immunity and development. In Arabidopsis (Arabidopsis thaliana), the receptor for the elicitor-active peptide epitope of bacterial flagellin, flg22, is encoded by FLAGELLIN SENSING2 (FLS2), which promotes

  2. [Study of the receptor for black widow spider neurotoxin. I. Characteristics of membrane-bound and solubilized receptors from the bovine brain].

    Science.gov (United States)

    Petrenko, A G; Shamotienko, O G; Surkova, I N; Kovalenko, V A; Grishin, E V

    1990-02-01

    Iodine-125 labelled alpha-latrotoxin from the venom of Central Asia black widow spider Latrodectus mactans tredecimguttatus binds specifically to the bovine brain membrane receptor producing a stable slowly dissociating complex with Kd = 1.6 x 10(-10) M and Bmax = 0.5 pmol/mg protein. Treatment of the complex with alkaline high-salt buffer induces reversible dissociation of the bound toxin. The antitoxin polyclonal antibody does not increase the dissociation rate of the bound toxin. Wheat germ lectin as well as concanavalin A inhibit the toxin binding to the membrane receptor. The receptor is solubilized with ionic and non-ionic detergents, and methods of latrotoxin binding assay are developed. The solubilized receptor is shown to retain high affinity to toxin, its binding activity being stable but critically dependent on the presence of calcium ions. Chromatographic properties of the receptor suggest its glycoprotein nature.

  3. Decreased endogenous progesterone and ratio of progesterone to ...

    African Journals Online (AJOL)

    PRECIOUS

    2010-02-01

    Feb 1, 2010 ... Decreased endogenous progesterone and ratio of progesterone to estrogen in stroke ischemia. Nasrin Sheikh1, Heidar Tavilani1* and Aliakbar Rezaie2. 1Department of Biochemistry, School of Medicine Hamadan University of Medical Sciences, Hamadan, Iran. 2Department of Neurology, School of ...

  4. Hemin inhibits internalization of transferrin by reticulocytes and promotes phosphorylation of the membrane transferrin receptor

    International Nuclear Information System (INIS)

    Cox, T.M.; O'Donnell, M.W.; Aisen, P.; London, I.M.

    1985-01-01

    Addition of hemin to reticulocytes inhibits incorporation of iron from transferrin. Heme also regulates protein synthesis in immature erythroid cells through its effects on phosphorylation of the initiation factor eIF-2. The authors have examined its effects on endocytosis of iron-transferrin and phosphorylation of the transferrin receptor. Hemin reduced iron transport but increased cell-associated transferrin. During uptake of 125 I-labeled transferrin in the steady state, the use of a washing technique to dissociate bound transferrin on the cell membrane showed that radioligand accumulated on the surface of hemin-treated cells. Receptor phosphorylation was investigated by immunoprecipitation of reticulocyte extracts after metabolic labeling with [ 32 P]P/sub i/. In the absence of ligand, phosphorylated receptor was chiefly localized on cell stroma. Exposure to transferrin increased cytosolic phosphorylated receptor from 15-30% to approximately 50% of the total, an effect overcome by hemin treatment. The findings suggest a possible relationship of phosphorylation to endocytosis of the transferrin receptor in reticulocytes

  5. Ligand-modulated conformational switching in a fully synthetic membrane-bound receptor

    Science.gov (United States)

    Lister, Francis G. A.; Le Bailly, Bryden A. F.; Webb, Simon J.; Clayden, Jonathan

    2017-05-01

    Signal transduction through G-protein-coupled receptors (GPCRs) involves binding to signalling molecules at the cell surface, which leads to global changes in molecular conformation that are communicated through the membrane. Artificial mechanisms for communication involving ligand binding and global conformational switching have been demonstrated so far only in the solution phase. Here, we report a membrane-bound synthetic receptor that responds to binding of a ligand by undergoing a conformational change that is propagated over several nanometres, deep into the phospholipid bilayer. Our design uses a helical foldamer core, with structural features borrowed from a class of membrane-active fungal antibiotics, ligated to a water-compatible, metal-centred binding site and a conformationally responsive fluorophore. Using the fluorophore as a remote reporter of conformational change, we find that binding of specific carboxylate ligands to a Cu(II) cofactor at the binding site perturbs the foldamer's global conformation, mimicking the conformational response of a GPCR to ligand binding.

  6. Coupling of guanine nucleotide inhibitory protein to somatostatin receptors on pancreatic acinar membranes

    International Nuclear Information System (INIS)

    Sakamoto, C.; Matozaki, T.; Nagao, M.; Baba, S.

    1987-01-01

    Guanine nucleotides and pertussis toxin were used to investigate whether somatostatin receptors interact with the guanine nucleotide inhibitory protein (NI) on pancreatic acinar membranes in the rat. Guanine nucleotides reduced 125 I-[Tyr 1 ]somatostatin binding to acinar membranes up to 80%, with rank order of potency being 5'-guanylyl imidodiphosphate [Gpp(NH)p]>GTP>TDP>GMP. Scatchard analysis revealed that the decrease in somatostatin binding caused by Gpp(NH)p was due to the decrease in the maximum binding capacity without a significant change in the binding affinity. The inhibitory effect of Gpp(NH)p was partially abolished in the absence of Mg 2+ . When pancreatic acini were treated with 1 μg/ml pertussis toxin for 4 h, subsequent 125 I-[Tyr 1 ]somatostatin binding to acinar membranes was reduced. Pertussis toxin treatment also abolished the inhibitory effect of somatostatin on vasoactive intestinal peptide-stimulated increase in cellular content of adenosine 3',5'-cyclic monophosphate (cAMP) in the acini. The present results suggest that 1) somatostatin probably functions in the pancreas to regulate adenylate cyclase enzyme system via Ni, 2) the extent of modification of Ni is correlated with the ability of somatostatin to inhibit cAMP accumulation in acini, and 3) guanine nucleotides also inhibit somatostatin binding to its receptor

  7. Membrane androgen receptor characteristics of human ZIP9 (SLC39A) zinc transporter in prostate cancer cells: Androgen-specific activation and involvement of an inhibitory G protein in zinc and MAP kinase signaling.

    Science.gov (United States)

    Thomas, Peter; Pang, Yefei; Dong, Jing

    2017-05-15

    Characteristics of novel human membrane androgen receptor (mAR), ZIP9 (SLC39A9), were investigated in ZIP9-transfected PC-3 cells (PC3-ZIP9). Ligand blot analysis showed plasma membrane [ 3 H]-T binding corresponds to the position of ZIP9 on Western blots which suggests ZIP9 can bind [ 3 H]-T alone, without a protein partner. Progesterone antagonized testosterone actions, blocking increases in zinc, Erk phosphorylation and apoptosis, further evidence that ZIP9 is specifically activated by androgens. Pre-treatment with GTPγS and pertussis toxin decreased plasma membrane [ 3 H]-T binding and blocked testosterone-induced increases in Erk phosphorylation and intracellular zinc, indicating ZIP9 is coupled to an inhibitory G protein (Gi) that mediates both MAP kinase and zinc signaling. Testosterone treatment of nuclei and mitochondria which express ZIP9 decreased their zinc contents, suggesting ZIP9 also regulates free zinc through releasing it from these intracellular organelles. The results show ZIP9 is a specific Gi coupled-mAR mediating testosterone-induced MAP kinase and zinc signaling in PC3-ZIP9 cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Characterization of the Ca2+ Channels Involved in the Progesterone ...

    African Journals Online (AJOL)

    There is evidence that intracellular Ca2+ concentration plays significant roles in sperm function such as motility and acrosome reaction. Many calcium channels have been identified in the plasma membrane of sperm. Progesterone (P4) stimulates Ca2+ influx and acrosome reaction in human spermatozoa. The effects of ...

  9. The role of progesterone in prevention of preterm birth

    Directory of Open Access Journals (Sweden)

    Jodie M Dodd

    2009-07-01

    Full Text Available Jodie M Dodd, Caroline A CrowtherDiscipline of Obstetrics and Gynaecology, The University of Adelaide, Adelaide, South Australia, AustraliaAbstract: Preterm birth continues to provide an enormous challenge in the delivery of perinatal health care, and is associated with considerable short and long-term health consequences for surviving infants. Progesterone has a role in maintaining pregnancy, by suppression of the calcium–calmodulin–myosin light chain kinase system. Additionally, progesterone has recognized anti-inflammatory properties, raising a possible link between inflammatory processes, alterations in progesterone receptor expression and the onset of preterm labor. Systematic reviews of randomized controlled trials evaluating the use of intramuscular and vaginal progesterone in women considered to be at increased risk of preterm birth have been published, with primary outcomes of perinatal death, preterm birth <34 weeks, and neurodevelopmental handicap in childhood. Eleven randomized controlled trials were included in the systematic review, involving 2714 women and 3452 infants, with results presented according to the reason women were considered to be at increased risk of preterm birth. While there is a potential beneficial effect in the use of progesterone for some women considered to be at increased risk of preterm birth, primarily in the reduction in the risk of preterm birth before 34 weeks gestation, it remains unclear if the observed prolongation of pregnancy translates into improved health outcomes for the infant.Keywords: progesterone, preterm birth, systematic review, randomized trial

  10. Progesterone Upregulates Gene Expression in Normal Human Thyroid Follicular Cells

    Directory of Open Access Journals (Sweden)

    Ana Paula Santin Bertoni

    2015-01-01

    Full Text Available Thyroid cancer and thyroid nodules are more prevalent in women than men, so female sex hormones may have an etiological role in these conditions. There are no data about direct effects of progesterone on thyroid cells, so the aim of the present study was to evaluate progesterone effects in the sodium-iodide symporter NIS, thyroglobulin TG, thyroperoxidase TPO, and KI-67 genes expression, in normal thyroid follicular cells, derived from human tissue. NIS, TG, TPO, and KI-67 mRNA expression increased significantly after TSH 20 μUI/mL, respectively: 2.08 times, P<0.0001; 2.39 times, P=0.01; 1.58 times, P=0.0003; and 1.87 times, P<0.0001. In thyroid cells treated with 20 μUI/mL TSH plus 10 nM progesterone, RNA expression of NIS, TG, and KI-67 genes increased, respectively: 1.78 times, P<0.0001; 1.75 times, P=0.037; and 1.95 times, P<0.0001, and TPO mRNA expression also increased, though not significantly (1.77 times, P=0.069. These effects were abolished by mifepristone, an antagonist of progesterone receptor, suggesting that genes involved in thyroid cell function and proliferation are upregulated by progesterone. This work provides evidence that progesterone has a direct effect on thyroid cells, upregulating genes involved in thyroid function and growth.

  11. Intestinal tumorigenesis is not affected by progesterone signaling in rodent models.

    Directory of Open Access Journals (Sweden)

    Jarom Heijmans

    Full Text Available Clinical data suggest that progestins have chemopreventive properties in the development of colorectal cancer. We set out to examine a potential protective effect of progestins and progesterone signaling on colon cancer development. In normal and neoplastic intestinal tissue, we found that the progesterone receptor (PR is not expressed. Expression was confined to sporadic mesenchymal cells. To analyze the influence of systemic progesterone receptor signaling, we crossed mice that lacked the progesterone receptor (PRKO to the Apc(Min/+ mouse, a model for spontaneous intestinal polyposis. PRKO-Apc(Min/+ mice exhibited no change in polyp number, size or localization compared to Apc(Min/+. To examine effects of progestins on the intestinal epithelium that are independent of the PR, we treated mice with MPA. We found no effects of either progesterone or MPA on gross intestinal morphology or epithelial proliferation. Also, in rats treated with MPA, injection with the carcinogen azoxymethane did not result in a difference in the number or size of aberrant crypt foci, a surrogate end-point for adenoma development. We conclude that expression of the progesterone receptor is limited to cells in the intestinal mesenchyme. We did not observe any effect of progesterone receptor signaling or of progestin treatment in rodent models of intestinal tumorigenesis.

  12. TTX-Resistant NMDA Receptor-Mediated Membrane Potential Oscillations in Neonatal Mouse Hb9 Interneurons

    Science.gov (United States)

    Masino, Mark A.; Abbinanti, Matthew D.; Eian, John; Harris-Warrick, Ronald M.

    2012-01-01

    Conditional neuronal membrane potential oscillations have been identified as a potential mechanism to help support or generate rhythmogenesis in neural circuits. A genetically identified population of ventromedial interneurons, called Hb9, in the mouse spinal cord has been shown to generate TTX-resistant membrane potential oscillations in the presence of NMDA, serotonin and dopamine, but these oscillatory properties are not well characterized. Hb9 interneurons are rhythmically active during fictive locomotor-like behavior. In this study, we report that exogenous N-Methyl-D-Aspartic acid (NMDA) application is sufficient to produce membrane potential oscillations in Hb9 interneurons. In contrast, exogenous serotonin and dopamine application, alone or in combination, are not sufficient. The properties of NMDA-induced oscillations vary among the Hb9 interneuron population; their frequency and amplitude increase with increasing NMDA concentration. NMDA does not modulate the T-type calcium current (ICa(T)), which is thought to be important in generating locomotor-like activity, in Hb9 neurons. These results suggest that NMDA receptor activation is sufficient for the generation of TTX-resistant NMDA-induced membrane potential oscillations in Hb9 interneurons. PMID:23094101

  13. In vitro membrane reconstitution of the T-cell receptor proximal signaling network.

    Science.gov (United States)

    Hui, Enfu; Vale, Ronald D

    2014-02-01

    T-cell receptor (TCR) phosphorylation is controlled by a complex network that includes Lck, a Src family kinase (SFK), the tyrosine phosphatase CD45 and the Lck-inhibitory kinase Csk. How these competing phosphorylation and dephosphorylation reactions are modulated to produce T-cell triggering is not fully understood. Here we reconstituted this signaling network using purified enzymes on liposomes, recapitulating the membrane environment in which they normally interact. We demonstrate that Lck's enzymatic activity can be regulated over an ~10-fold range by controlling its phosphorylation state. By varying kinase and phosphatase concentrations, we constructed phase diagrams that reveal ultrasensitivity in the transition from the quiescent to the phosphorylated state and demonstrate that co-clustering TCR and Lck or detaching Csk from the membrane can trigger TCR phosphorylation. Our results provide insight into the mechanism of TCR signaling as well as other signaling pathways involving SFKs.

  14. Fusion proteins and select lipids cooperate as membrane receptors for the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) Vam7p.

    Science.gov (United States)

    Karunakaran, Vidya; Wickner, William

    2013-10-04

    Vam7p, the vacuolar soluble Qc-SNARE, is essential for yeast vacuole fusion. The large tethering complex, homotypic fusion and vacuole protein sorting complex (HOPS), and phosphoinositides, which interact with the Vam7p PX domain, have each been proposed to serve as its membrane receptors. Studies with the isolated organelle cannot determine whether these receptor elements suffice and whether ligands or mutations act directly or indirectly on Vam7p binding to the membrane. Using pure components that are active in reconstituted vacuolar fusion, we now find that Vam7p binds to membranes through its combined affinities for several vacuolar membrane constituents: HOPS, phosphatidylinositol 3-phosphate, SNAREs, and acidic phospholipids. Acidic lipids allow low concentrations of Vam7p to suffice for fusion; without acidic lipids, the block to fusion is partially bypassed by high concentrations of Vam7p.

  15. Location of the sulphonylurea receptor at the cytoplasmic face of the beta-cell membrane.

    Science.gov (United States)

    Schwanstecher, M; Schwanstecher, C; Dickel, C; Chudziak, F; Moshiri, A; Panten, U

    1994-11-01

    1. In insulin-secreting cells the location of the sulphonylurea receptor was examined by use of a sulphonylurea derivative representing the glibenclamide molecule devoid of its cyclohexy moiety (compound III) and a benzenesulphonic acid derivative representing the glibenclamide molecule devoid of its cyclohexylurea moiety (compound IV). At pH 7.4 compound IV is only present in charged form. 2. Lipid solubility declined in the order tolbutamide > compound III > compound IV. 3. The dissociation constant (KD) for binding of compound IV to the sulphonylurea receptor in HIT-cells (pancreatic beta-cell line) was similar to the KD value for tolbutamide and fourfold higher than the KD value for compound III. 4. In mouse pancreatic beta-cells, drug concentrations inhibiting adenosine 5'-triphosphate-sensitive K+ channels (KATP-channels) half-maximally (EC50) were determined by use of the patch-clamp technique. When the drugs were applied to the extracellular side of outside-out or the intracellular side of inside-out membrane patches, the ratio of extracellular to intracellular EC50 values was 281 for compound IV, 25.5 for compound III and 1.2 for tolbutamide. 5. In mouse pancreatic beta-cells, measurement of KATP-channel activity in cell-attached patches and recording of insulin release displayed much higher EC50 values for compound IV than inside-out patch experiments. A corresponding, but less pronounced difference in EC50 values was observed for compound III, whereas the EC50 values for tolbutamide did not differ significantly. 6. It is concluded that the sulphonylurea receptor is located at the cytoplasmic face of the beta-cell plasma membrane. Receptor activation is induced by the anionic forms of sulphonylureas and their analogues.

  16. Plasma membrane cholesterol level and agonist-induced internalization of delta-opioid receptors; colocalization study with intracellular membrane markers of Rab family\

    Czech Academy of Sciences Publication Activity Database

    Brejchová, Jana; Vošahlíková, Miroslava; Roubalová, Lenka; Parenti, M.; Mauri, M.; Chernyavskiy, Oleksandr; Svoboda, Petr

    2016-01-01

    Roč. 48, č. 4 (2016), s. 375-396 ISSN 0145-479X R&D Projects: GA ČR(CZ) GAP207/12/0919 Institutional support: RVO:67985823 Keywords : cholesterol * plasma membrane * delta-opioid receptor * internalization * Rab proteins Subject RIV: CE - Biochemistry Impact factor: 2.576, year: 2016

  17. Dietary fiber intake and risk of breast cancer defined by estrogen and progesterone receptor status: the Japan Public Health Center-based Prospective Study.

    Science.gov (United States)

    Narita, Saki; Inoue, Manami; Saito, Eiko; Abe, Sarah K; Sawada, Norie; Ishihara, Junko; Iwasaki, Motoki; Yamaji, Taiki; Shimazu, Taichi; Sasazuki, Shizuka; Shibuya, Kenji; Tsugane, Shoichiro

    2017-06-01

    Epidemiological studies have suggested a protective effect of dietary fiber intake on breast cancer risk while the results have been inconsistent. Our study aimed to investigate the association between dietary fiber intake and breast cancer risk and to explore whether this association is modified by reproductive factors and hormone receptor status of the tumor. A total of 44,444 women aged 45 to 74 years from the Japan Public Health Center-based Prospective Study were included in analyses. Dietary intake assessment was performed using a validated 138-item food frequency questionnaire (FFQ). Hazard ratios (HRs) and 95% confidence intervals (CIs) for breast cancer incidence were calculated by multivariate Cox proportional hazards regression models. During 624,423 person-years of follow-up period, 681 breast cancer cases were identified. After adjusting for major confounders for breast cancer risk, inverse trends were observed but statistically non-significant. Extremely high intake of fiber was associated with decreased risk of breast cancer but this should be interpreted with caution due to limited statistical power. In stratified analyses by menopausal and hormone receptor status, null associations were observed except for ER-PR- status. Our findings suggest that extreme high fiber intake may be associated with decreased risk of breast cancer but the level of dietary fiber intake among Japanese population might not be sufficient to examine the association between dietary fiber intake and breast cancer risk.

  18. Progesterone stimulates adipocyte determination and differentiation 1/sterol regulatory element-binding protein 1c gene expression. potential mechanism for the lipogenic effect of progesterone in adipose tissue.

    Science.gov (United States)

    Lacasa, D; Le Liepvre, X; Ferre, P; Dugail, I

    2001-04-13

    Fatty acid synthase (FAS), a nutritionally regulated lipogenic enzyme, is transcriptionally controlled by ADD1/SREBP1c (adipocyte determination and differentiation 1/sterol regulatory element-binding protein 1c), through insulin-mediated stimulation of ADD1/SREBP1c expression. Progesterone exerts lipogenic effects on adipocytes, and FAS is highly induced in breast tumor cell lines upon progesterone treatment. We show here that progesterone up-regulates ADD1/SREBP1c expression in the MCF7 breast cancer cell line and the primary cultured preadipocyte from rat parametrial adipose tissue. In MCF7, progesterone induced ADD1/SREBP1c and Metallothionein II (a well known progesterone-regulated gene) mRNAs, with comparable potency. In preadipocytes, progesterone increased ADD1/SREBP1c mRNA dose-dependently, but not SREBP1a or SREBP2. Run-on experiments demonstrated that progesterone action on ADD1/SREBP1c was primarily at the transcriptional level. The membrane-bound and mature nuclear forms of ADD1/SREBP1 protein accumulated in preadipocytes cultured with progesterone, and FAS induction could be abolished by adenovirus-mediated overexpression of a dominant negative form of ADD1/SREBP1 in these cells. Finally, in the presence of insulin, progesterone was unable to up-regulate ADD1/SREBP1c mRNA in preadipocytes, whereas its effect was restored after 24 h of insulin deprivation. Together these results demonstrate that ADD1/SREBP1c is controlled by progesterone, which, like insulin, acts by increasing ADD1/SREBP1c gene transcription. This provides a potential mechanism for the lipogenic actions of progesterone on adipose tissue.

  19. Binding constants of membrane-anchored receptors and ligands: A general theory corroborated by Monte Carlo simulations.

    Science.gov (United States)

    Xu, Guang-Kui; Hu, Jinglei; Lipowsky, Reinhard; Weikl, Thomas R

    2015-12-28

    Adhesion processes of biological membranes that enclose cells and cellular organelles are essential for immune responses, tissue formation, and signaling. These processes depend sensitively on the binding constant K2D of the membrane-anchored receptor and ligand proteins that mediate adhesion, which is difficult to measure in the "two-dimensional" (2D) membrane environment of the proteins. An important problem therefore is to relate K2D to the binding constant K3D of soluble variants of the receptors and ligands that lack the membrane anchors and are free to diffuse in three dimensions (3D). In this article, we present a general theory for the binding constants K2D and K3D of rather stiff proteins whose main degrees of freedom are translation and rotation, along membranes and around anchor points "in 2D," or unconstrained "in 3D." The theory generalizes previous results by describing how K2D depends both on the average separation and thermal nanoscale roughness of the apposing membranes, and on the length and anchoring flexibility of the receptors and ligands. Our theoretical results for the ratio K2D/K3D of the binding constants agree with detailed results from Monte Carlo simulations without any data fitting, which indicates that the theory captures the essential features of the "dimensionality reduction" due to membrane anchoring. In our Monte Carlo simulations, we consider a novel coarse-grained model of biomembrane adhesion in which the membranes are represented as discretized elastic surfaces, and the receptors and ligands as anchored molecules that diffuse continuously along the membranes and rotate at their anchor points.

  20. Differential expression of epidermal growth factor receptor (EGF-R) gene and regulation of EGF-R bioactivity by progesterone and estrogen in the adult mouse uterus.

    Science.gov (United States)

    Das, S K; Tsukamura, H; Paria, B C; Andrews, G K; Dey, S K

    1994-02-01

    The present study examined several aspects of epidermal growth factor receptor (EGF-R) in the mouse uterus during the peri-implantation period and after ovarian hormone treatment of adult ovariectomized mice. The cell-specific distribution, regulation of expression, and binding kinetics were assessed by immunohistochemistry, Northern blot analysis, and ligand binding assays, respectively. Affinity cross-linking studies ascertained the size of the EGF-R, and its bioactivity was examined by determining EGF-dependent subcellular protein tyrosine kinase activity and receptor autophosphorylation. In the intact uterus and separated cell types, EGF-R was detected in the stroma, deciduum, and myometrium, but not in the luminal or glandular epithelium. Uterine EGF-R mRNA transcript profiles showed some differences between pregnant and ovariectomized mice regardless of steroid hormone treatments. Two major [6.5- and 2.7-kilobase (kb)] and two less abundant (9.6- and 5.0-kb) transcripts were detected in pregnant uterine poly(A)+ RNA. Three additional transcripts (oil or P4. E2 treatment was found to be essential for EGF-R bioactivity. Taken together, the results suggest that in the adult mouse uterus, EGF-R status is influenced by factors other than P4 and E2, the epithelium is not the direct target for the actions of EGF-related growth factors as thought previously, the mitogenic effects of these growth factors on epithelial cells in vivo are perhaps mediated by other uterine cell-types expressing EGF-R, and, lastly, these growth factors are not likely to be functional in the uterus in the absence of estrogen. The present observations are supportive of the concept of paracrine or juxtacrine interactions between EGF-related growth factor ligands of luminal epithelial origin and blastocyst EGF-R in the process of implantation.

  1. Peptide Phage Display as a Tool for Drug Discovery: Targeting Membrane Receptors

    Directory of Open Access Journals (Sweden)

    Tomaz Bratkovic

    2011-01-01

    Full Text Available Ligands selected from phage-displayed random peptide libraries tend to be directed to biologically relevant sites on the surface of the target protein. Consequently, peptides derived from library screenings often modulate the target protein’s activity in vitro and in vivo and can be used as lead compounds in drug design and as alternatives to antibodies for target validation in both genomics and drug discovery. This review discusses the use of phage display to identify membrane receptor modulators with agonistic or antagonistic activities. Because isolating or producing recombinant membrane proteins for use as target molecules in library screening is often impossible, innovative selection strategies such as panning against whole cells or tissues, recombinant receptor ectodomains, or neutralizing antibodies to endogenous binding partners were devised. Prominent examples from a two-decade history of peptide phage display will be presented, focusing on the design of affinity selection experiments, methods for improving the initial hits, and applications of the identified peptides.

  2. The neurosteroid progesterone underlies estrogen positive feedback of the LH surge

    Directory of Open Access Journals (Sweden)

    Paul E Micevych

    2011-12-01

    Full Text Available Our understanding the steroid regulation of neural function has rapidly evolved in the past decades. Not long ago the prevailing thoughts were that peripheral steroid hormones carried information to the brain which passively responded to these steroids. These steroid actions were slow, taking hours to days to be realized because they regulated gene expression. Over the past three decades, discoveries of new steroid receptors, rapid membrane initiated signaling mechanisms and de novo neurosteroidogenesis have shed new light on the complexity of steroids actions within the nervous system. Sexual differentiation of the brain during development occurs predominately through timed steroid-mediated expression of proteins and long term epigenetic modifications. In contrast across the estrous cycle, estradiol release from developing ovarian follicles initially increases slowly and then at proestrus increases rapidly. This pattern of estradiol release acts through both classical genomic mechanisms and rapid membrane-initiated signaling in the brain to coordinate reproductive behavior and physiology. This review focuses on recently discovered estrogen receptor- (ER membrane signaling mechanisms that estradiol utilizes during estrogen positive feedback to stimulate de novo progesterone synthesis within the hypothalamus to trigger the luteinizing hormone surge important for ovulation and estrous cyclicity. The activation of these signaling pathways appears to be coordinated by the rising and waning of estradiol throughout the estrous cycle and integral to the negative and positive feedback mechanisms of estradiol. This differential responsiveness is part of the timing mechanism triggering the luteinizing hormone surge.

  3. Linoleic acid derivative DCP-LA stimulates vesicular transport of α7 ACh receptors towards surface membrane.

    Science.gov (United States)

    Kanno, Takeshi; Tanaka, Akito; Nishizaki, Tomoyuki

    2012-01-01

    We have earlier found that the linoleic acid derivative DCP-LA could ameliorate learning and memory impairment by targeting α7 ACh receptor. The present study aimed at understanding DCP-LA-regulated α7 ACh receptor trafficking. We monitored currents through α7 ACh receptors expressed in Xenopus oocytes and assayed the receptor mobilizations using fractions with a sucrose density gradient centrifugation, synaptosome preparation, and acutely dissociated neurons from rat hippocampal slices. DCP-LA persistently potentiated α7 ACh receptor currents, and the effect was inhibited by a protein kinase C (PKC) inhibitor or vesicular transport inhibitors. DCP-LA did not induce PKC phosphorylation of α7 ACh receptors. DCP-LA stimulated translocation of α7 ACh receptors from the cytosol toward the plasma membrane or from extra-synaptosomes into synaptosomes and accumulated the receptors at the presynaptic site in hippocampal neurons. The results of the present study demonstrate that DCP-LA increases surface localization of α7 ACh receptors in hippocampal neurons, specifically at presynaptic terminals, by stimulating vesicular transport of the receptors, resulting in potentiation of α7 ACh receptor responses, regardless of PKC phosphorylation of the receptors. Copyright © 2012 S. Karger AG, Basel.

  4. Investigation of Membrane Receptors' Oligomers Using Fluorescence Resonance Energy Transfer and Multiphoton Microscopy in Living Cells

    Science.gov (United States)

    Mishra, Ashish K.

    Investigating quaternary structure (oligomerization) of macromolecules (such as proteins and nucleic acids) in living systems (in vivo) has been a great challenge in biophysics, due to molecular diffusion, fluctuations in several biochemical parameters such as pH, quenching of fluorescence by oxygen (when fluorescence methods are used), etc. We studied oligomerization of membrane receptors in living cells by means of Fluorescence (Forster) Resonance Energy Transfer (FRET) using fluorescent markers and two photon excitation fluorescence micro-spectroscopy. Using suitable FRET models, we determined the stoichiometry and quaternary structure of various macromolecular complexes. The proteins of interest for this work are : (1) sigma-1 receptor and (2) rhodopsin, are described as below. (1) Sigma-1 receptors are molecular chaperone proteins, which also regulate ion channels. S1R seems to be involved in substance abuse, as well as several diseases such as Alzheimer's. We studied S1R in the presence and absence of its ligands haloperidol (an antagonist) and pentazocine +/- (an agonist), and found that at low concentration they reside as a mixture of monomers and dimers and that they may form higher order oligomers at higher concentrations. (2) Rhodopsin is a prototypical G protein coupled receptor (GPCR) and is directly involved in vision. GPCRs form a large family of receptors that participate in cell signaling by responding to external stimuli such as drugs, thus being a major drug target (more than 40% drugs target GPCRs). Their oligomerization has been largely controversial. Understanding this may help to understand the functional role of GPCRs oligomerization, and may lead to the discovery of more drugs targeting GPCR oligomers. It may also contribute toward finding a cure for Retinitis Pigmentosa, which is caused by a mutation (G188R) in rhodopsin, a disease which causes blindness and has no cure so far. Comparing healthy rhodopsin's oligomeric structure with that

  5. Cost-effectiveness of a 21-gene recurrence score assay versus Canadian clinical practice in women with early-stage estrogen- or progesterone-receptor-positive, axillary lymph-node negative breast cancer

    International Nuclear Information System (INIS)

    Hannouf, Malek B; Xie, Bin; Brackstone, Muriel; Zaric, Gregory S

    2012-01-01

    A 21-gene recurrence score (RS) assay may inform adjuvant systematic treatment decisions in women with early stage breast cancer. We sought to investigate the cost effectiveness of using the RS-assay versus current clinical practice (CCP) in women with early-stage estrogen- or progesterone-receptor-positive, axilliary lymph-node negative breast cancer (ER+/ PR + LN- ESBC) from the perspective of the Canadian public healthcare system. We developed a Markov model to project the lifetime clinical and economic consequences of ESBC. We evaluated adjuvant therapy separately in post- and pre-menopausal women with ER+/ PR + LN- ESBC. We assumed that the RS-assay would reclassify pre- and post-menopausal women among risk levels (low, intermediate and high) and guide adjuvant systematic treatment decisions. The model was parameterized using 7 year follow up data from the Manitoba Cancer Registry, cost data from Manitoba administrative databases, and secondary sources. Costs are presented in 2010 CAD. Future costs and benefits were discounted at 5%. The RS-assay compared to CCP generated cost-savings in pre-menopausal women and had an ICER of $60,000 per QALY gained in post-menopausal women. The cost effectiveness was most sensitive to the proportion of women classified as intermediate risk by the RS-assay who receive adjuvant chemotherapy and the risk of relapse in the RS-assay model. The RS-assay is likely to be cost effective in the Canadian healthcare system and should be considered for adoption in women with ER+/ PR + LN- ESBC. However, ongoing assessment and validation of the assay in real-world clinical practice is warranted

  6. P2X-Receptor Antagonists Inhibit the Interaction of S. aureus Hemolysin A with Membranes

    Directory of Open Access Journals (Sweden)

    Markus Schwiering

    2017-10-01

    Full Text Available The pore forming hemolysin A, Hla, is a major virulence factor of Staphylococcus aureus. Apparently, 1–2 pore(s per cell suffice(s to cause cell death. Accumulated experimental evidence points towards a major role of ATP-gated purinergic receptors (P2XR for hemolysis caused by Hla, complement and other pore forming proteins, presumably by increasing membrane permeability. Indeed, in experiments employing rabbit erythrocytes, inhibitory concentrations of frequently employed P2XR-antagonists were in a similar range as previously reported for erythrocytes of other species and other toxins. However, Hla-dependent hemolysis was not enhanced by extracellular ATP, and oxidized adenosinetriphosphate (oxATP had only a minor inhibitory effect. Unexpectedly, P2XR-inhibitors also prevented Hla-induced lysis of pure lipid membranes, demonstrating that the inhibition did not even depend on the presence of P2XR. Fluorescence microscopy and gel-electrophoresis clearly revealed that P2XR-inhibitors interfere with binding and subsequent oligomerisation of Hla with membranes. Similar results were obtained employing HaCaT-cells. Furthermore, calorimetric data and hemolysis experiments with Hla pre-treated with pyridoxal phosphate-6-azophenyl-2′,4′-disulfonic acid (PPADS showed that this compound directly binds to Hla. Our results call for a critical re-assessment of the appealing concept, which suggests that P2XR are general amplifiers of damage by pore-forming proteins.

  7. The Affinity of Elongated Membrane-Tethered Ligands Determines Potency of T Cell Receptor Triggering

    Directory of Open Access Journals (Sweden)

    Bing-Mae Chen

    2017-07-01

    Full Text Available T lymphocytes are important mediators of adoptive immunity but the mechanism of T cell receptor (TCR triggering remains uncertain. The interspatial distance between engaged T cells and antigen-presenting cells (APCs is believed to be important for topological rearrangement of membrane tyrosine phosphatases and initiation of TCR signaling. We investigated the relationship between ligand topology and affinity by generating a series of artificial APCs that express membrane-tethered anti-CD3 scFv with different affinities (OKT3, BC3, and 2C11 in addition to recombinant class I and II pMHC molecules. The dimensions of membrane-tethered anti-CD3 and pMHC molecules were progressively increased by insertion of different extracellular domains. In agreement with previous studies, elongation of pMHC molecules or low-affinity anti-CD3 scFv caused progressive loss of T cell activation. However, elongation of high-affinity ligands (BC3 and OKT3 scFv did not abolish TCR phosphorylation and T cell activation. Mutation of key amino acids in OKT3 to reduce binding affinity to CD3 resulted in restoration of topological dependence on T cell activation. Our results show that high-affinity TCR ligands can effectively induce TCR triggering even at large interspatial distances between T cells and APCs.

  8. Oestrogen inhibits human colonic motility by a non-genomic cell membrane receptor-dependent mechanism.

    LENUS (Irish Health Repository)

    Hogan, A M

    2012-02-01

    BACKGROUND: Classical effects of oestrogen involve activation of target genes after binding nuclear receptors. Oestrogenic effects too rapid for DNA transcription (non-genomic) are known to occur. The effect of oestrogen on colonic motility is unknown despite the prevalence of gastrointestinal symptoms in pregnant and premenopausal women. METHODS: Histologically normal colon was obtained from proximal resection margins of colorectal carcinoma specimens. Circular smooth muscle strips were microdissected and suspended in organ baths under 1 g of tension. After equilibration, they were exposed to 17beta-oestradiol (n = 8) or bovine serum albumin (BSA)-conjugated 17beta-oestradiol (n = 8). Fulvestrant, an oestrogen receptor antagonist, was added to some baths (n = 8). Other strips were exposed to calphostin C or cycloheximide. Carbachol was added in increasing concentrations and contractile activity was recorded isometrically. RESULTS: Oestrogen inhibited colonic contractility (mean difference 19.7 per cent; n = 8, P < 0.001). In keeping with non-genomic, rapid-onset steroid action, the effect was apparent within minutes and reversible. It was observed with both 17beta-oestradiol and BSA-conjugated oestrogen, and was not altered by cycloheximide. Effects were inhibited by fulvestrant, suggesting receptor mediation. CONCLUSION: Oestrogen decreases contractility in human colonic smooth muscle by a non-genomic mechanism involving cell membrane coupling.

  9. Lipid domain formation and ligand-receptor distribution in lipid bilayer membranes investigated by atomic force microscopy

    DEFF Research Database (Denmark)

    Kaasgaard, Thomas; Mouritsen, O.G.; Jørgensen, K.

    2002-01-01

    A novel experimental technique, based on atomic force microscopy (AFM), is proposed to visualize the lateral organization of membrane systems in the nanometer range. The technique involves the use of a ligand-receptor pair, biotin-avidin, which introduces a height variation on a solid-supported l......A novel experimental technique, based on atomic force microscopy (AFM), is proposed to visualize the lateral organization of membrane systems in the nanometer range. The technique involves the use of a ligand-receptor pair, biotin-avidin, which introduces a height variation on a solid...

  10. Structure and function of the Juxta membrane domain of the human epidermal growth factor receptor by NMR spectroscopy

    International Nuclear Information System (INIS)

    Choowongkomon, Kiattawee; Carlin, Cathleen; Sonnichsen, Frank D.

    2005-10-01

    The epidermal growth factor receptor (EGFR) is a member of the receptor tyrosine kinase family involved in the regulation of cellular proliferation and differentiation. Its juxta membrane domain (JX), the region located between the transmembrane and kinase domains, plays important roles in receptor trafficking since both basolateral sorting in polarized epithelial cells and lysosomal sorting signals are identified in this region. In order to understand the regulation of these signals, we characterized the structural properties of recombinant JX domain in dodecyl phosphocholine detergent (DPC) by nuclear magnetic resonance (NMR) spectroscopy. In DPC micelles, structures derived from NMR data showed three amphipathic, helical segments. Two equivalent average structural models on the surface of micelles were obtained that differ only in the relative orientation between the first and second helices. Our data suggests that the activity of sorting signals may be regulated by their membrane association and restricted accessibility in the intact receptor

  11. [Transcriptional regulation effect of THSG and anthraquinones in tubers of Polygonum multiflorum based on human progesterone X receptor (PXR) mediated CYP3A4 rapid screening system].

    Science.gov (United States)

    Zhang, Zhao-Yan; Yang, Liang; Huang, Xiao-Yan; Wang, Mei-Xi; Ma, Zeng-Chun; Tang, Xiang-Lin; Wang, Yu-Guang; Gao, Yue

    2017-12-01

    The rapid screening technology was used to investigate the transcriptional regulation effect of main chemical constituents in tubers of Polygonum multiflorum, including 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucopyranoside(THSG) and anthraquinones (such as rhein, chrysophanol, aloe-emodin, emodin) on CYP3A4 drug inducers induced by human pregnancy X receptor (PXR).The effect of chemical composition on the cell activity was detected by MTS cell viability assay. IC₅₀ was calculated. The expression vector and the reporter vector were co-transfected into HepG2 cells, with 10 μmol•L⁻¹ rifampicin (RIF) as a positive control, and 10 μmol•L⁻¹ ketoconazole (TKZ) as a negative control. After treated with different concentrations of anthraquinones (2.5, 5, 10 μmol•L⁻¹) for 24 h, the cells were tested for dual luciferase activity. The results show that the inhibitory effect of THSG, chrysophanol, emodin, rhein and aloe-emodin on CYP3A4 was inhibited by co-transfection of pcDNA3.1 and pGL4.17-CYP3A4. The expressions of pcDNA3.14-PXR and pGL4.17-CYP3A4 were induced by the four compounds. Besides, emodin had a direct inducing effect. In conclusion, the four anthraquinone compounds have an inducing effect on CYP3A4 by PXR, but emodin can directly induce CYP3A4. THSG can inhibit CYP3A4, but plasmid can induce CYP3A4 after intervened with PXR.These results suggest that we should pay attention to the liver function and avoid liver damage in the combined administration of drugs. Copyright© by the Chinese Pharmaceutical Association.

  12. MEMBRANE OESTROGEN RECEPTORS ON RAT PITUITARY TUMOUR CELLS: IMMUNO-IDENTIFICATION AND RESPONSES TO OESTRADIOL AND XENOESTROGENS

    Science.gov (United States)

    WATSON, CHERYL S.; CAMPBELL, CELESTE H.; GAMETCHU, BAHIRU

    2007-01-01

    SUMMARY Our laboratory has identified plasma membrane oestrogen receptors on a GH3/B6 rat pituitary tumour cell line and several sublines which produce rapid (within minutes), non-genomic responses to oestrogens. Oestrogen receptors have been identified by their binding to nine different antibodies (Abs) which together recognize at least seven epitopes on the oestrogen receptor-α. GH3/B6/F10 cells, a membrane oestrogen receptor-enriched subline, elevate intracellular calcium levels in response to 10 nM oestradiol. Prolactin release in these cells is triggered by both 1 pM and 1 nM oestradiol and diethylstilbestrol (DES). A membrane oestrogen receptor-α immunocyto-chemical signal rapidly disappears (at 3 min) and reappears (at 12–15 min) when 1 nM oestradiol, 10 nM diethylstilbestrol, or 10 nM nonylphenol is applied to the cells. This suggests that both oestrogens and xenoestrogens can utilize this alternative pathway for oestrogenic action. Xenoestrogens, which have so far shown weak effects in genomic assay systems, should now be retested for activity in eliciting membrane-initiated oestrogenic responses. PMID:10564698

  13. Lipid raft localization of TLR2 and its co-receptors is independent of membrane lipid composition

    Directory of Open Access Journals (Sweden)

    Christine Hellwing

    2018-01-01

    Full Text Available Background Toll like receptors (TLRs are an important and evolutionary conserved class of pattern recognition receptors associated with innate immunity. The recognition of Gram-positive cell wall constituents strongly depends on TLR2. In order to be functional, TLR2 predominantly forms a heterodimer with TLR1 or TLR6 within specialized membrane microdomains, the lipid rafts. The membrane lipid composition and the physicochemical properties of lipid rafts are subject to modification by exogenous fatty acids. Previous investigations of our group provide evidence that macrophage enrichment with polyunsaturated fatty acids (PUFA induces a reordering of lipid rafts and non-rafts based on the incorporation of supplemented PUFA as well as their elongation and desaturation products. Methods In the present study we investigated potential constraining effects of membrane microdomain reorganization on the clustering of TLR2 with its co-receptors TLR1 and TLR6 within lipid rafts. To this end, RAW264.7 macrophages were supplemented with either docosahexaenoic acid (DHA or arachidonic acid (AA and analyzed for receptor expression and microdomain localization in context of TLR stimulation. Results and Conclusions Our analyses showed that receptor levels and microdomain localization were unchanged by PUFA supplementation. The TLR2 pathway, in contrast to the TLR4 signaling cascade, is not affected by exogenous PUFA at the membrane level.

  14. The Membrane Proximal Region of AMPA Receptors in Lateral Amygdala is Essential for Fear Memory Formation.

    Science.gov (United States)

    Ganea, Dan A; Dines, Monica; Basu, Sreetama; Lamprecht, Raphael

    2015-11-01

    The membrane proximal region (MPR) of AMPA receptor (AMPAR) is needed for receptor trafficking and synaptic plasticity. However, its roles in long-term memory formation are not known. To assess the possible roles of AMPAR-MPR in rat lateral amygdala (LA) in short- and long-term fear memory formation, we used glutamate receptors (GluAs)-MPR competitive peptides MPR(DD) and MPR(AA). The MPR(DD) peptide is derived from GluA1 MPR and was previously shown to impair synaptic plasticity and to inhibit GluA1 containing AMPAR insertion into the synapse in an activity-dependent manner. The MPR(AA) peptide is derived from GluA2/4 MPR, and this receptor fragment was shown to be essential for GluA4 protein interaction needed for its insertion into the neuronal membrane and synapse. The peptides were linked to a TAT peptide (TAT-MPR(DD) and TAT-MPR(AA)) to facilitate internalization into LA cells. Infusion of the TAT-MPR(DD) peptide into LA 30 min before fear conditioning led to a significant impairment of long-term fear memory formation. Injection of TAT-MPR(DD) peptide into LA 30 min before fear conditioning impaired short-term fear memory formation. The TAT-MPR(DD) peptide had no effect on memory retrieval when injected into LA 30 min before fear memory test. Infusion of the TAT-MPR(AA) peptide into LA 30 min before fear conditioning led to a significant impairment of long-term fear memory formation. In contrast, the TAT-MPR(AA) had no effect on short-term fear memory formation. A TAT-control peptide had no effect on short- or long-term fear memory. These results show that the AMPAR-MPR in LA is needed for fear memory formation and that the MPR region of GluA1 is essential for acquisition of memory, whereas the MPR region of GluA4 is essential for long-term fear memory consolidation.

  15. Immunohistochemical expression of oestrogen and progesterone receptors during experimental acute and chronic murine Schistosomiasis mansoni Expressão imunohistoquímica de receptores para estrogênio e progesterona nas fases aguda e crônica da esquistossomose mansônica experimental em camundongos

    Directory of Open Access Journals (Sweden)

    Fawzia Ahmed Habib

    2010-10-01

    Full Text Available INTRODUCTION: The responsibility of Schistosoma mansoni in female infertility is still controversial. This study was conducted to evaluate the effect of acute and chronic schistosomiasis mansoni infection on the endometrium using immunohistochemical analysis of uterine hormone receptor expression. METHODS: Twenty-four nonpregnant swiss albino mice were divided into three groups: control, noninfected; acute; and chronic Schistosoma mansoni infection. Histological sections of uterine specimens were examined by light microscope with an image analyzing system to detect structural histological, estrogen receptor (ER and progesterone receptor (PR expression in the endometrium. RESULTS: No secretory phase was detected in the endometrium in acute and chronic Schistosoma infection. Hormone receptor expression (ER and PR showed statistically significant differences among the groups (pINTRODUÇÃO: A responsabilidade do Schistosoma mansoni em esterilidade feminina é ainda controversa. Este estudo é conduzido para avaliar o efeito da esquistossomose mansoni aguda e crônica no endométrio usando análise de imuno-histoquímíca da expressão de receptor hormonal uterina. MÉTODOS: Vinte e quatro camundongos fêmeas albinas suíças não grávidas foram divididas em 3 grupos (controle não-infectado, grupos agudos e crônicos infeccionados com Schistosoma mansoni. As seções histológicas de espécimes uterinos foram examinadas por microscópio leve com imagem, analisando sistema para detectar no endométrio expressões histológicas estruturais, receptor de estrogênio (ER e receptor de progesterona (PR. RESULTADOS: Nenhuma fase secretora foi detectada no endométrio com infecção aguda e crônica de Schistosoma. A expressão hormonal de receptor (ER e PR mostrou diferenças estatisticamente significantes entre grupos diferentes (p<0,05 com baixa significativa hormonal de ER com infecção crônica (comparado com controle proliferativo, controle secret

  16. The human gonadotropin releasing hormone type I receptor is a functional intracellular GPCR expressed on the nuclear membrane.

    Directory of Open Access Journals (Sweden)

    Michelle Re

    Full Text Available The mammalian type I gonadotropin releasing hormone receptor (GnRH-R is a structurally unique G protein-coupled receptor (GPCR that lacks cytoplasmic tail sequences and displays inefficient plasma membrane expression (PME. Compared to its murine counterparts, the primate type I receptor is inefficiently folded and retained in the endoplasmic reticulum (ER leading to a further reduction in PME. The decrease in PME and concomitant increase in intracellular localization of the mammalian GnRH-RI led us to characterize the spatial distribution of the human and mouse GnRH receptors in two human cell lines, HEK 293 and HTR-8/SVneo. In both human cell lines we found the receptors were expressed in the cytoplasm and were associated with the ER and nuclear membrane. A molecular analysis of the receptor protein sequence led us to identify a putative monopartite nuclear localization sequence (NLS in the first intracellular loop of GnRH-RI. Surprisingly, however, neither the deletion of the NLS nor the addition of the Xenopus GnRH-R cytoplasmic tail sequences to the human receptor altered its spatial distribution. Finally, we demonstrate that GnRH treatment of nuclei isolated from HEK 293 cells expressing exogenous GnRH-RI triggers a significant increase in the acetylation and phosphorylation of histone H3, thereby revealing that the nuclear-localized receptor is functional. Based on our findings, we conclude that the mammalian GnRH-RI is an intracellular GPCR that is expressed on the nuclear membrane. This major and novel discovery causes us to reassess the signaling potential of this physiologically and clinically important receptor.

  17. Distinct human and mouse membrane trafficking systems for sweet taste receptors T1r2 and T1r3.

    Science.gov (United States)

    Shimizu, Madoka; Goto, Masao; Kawai, Takayuki; Yamashita, Atsuko; Kusakabe, Yuko

    2014-01-01

    The sweet taste receptors T1r2 and T1r3 are included in the T1r taste receptor family that belongs to class C of the G protein-coupled receptors. Heterodimerization of T1r2 and T1r3 is required for the perception of sweet substances, but little is known about the mechanisms underlying this heterodimerization, including membrane trafficking. We developed tagged mouse T1r2 and T1r3, and human T1R2 and T1R3 and evaluated membrane trafficking in human embryonic kidney 293 (HEK293) cells. We found that human T1R3 surface expression was only observed when human T1R3 was coexpressed with human T1R2, whereas mouse T1r3 was expressed without mouse T1r2 expression. A domain-swapped chimera and truncated human T1R3 mutant showed that the Venus flytrap module and cysteine-rich domain (CRD) of human T1R3 contain a region related to the inhibition of human T1R3 membrane trafficking and coordinated regulation of human T1R3 membrane trafficking. We also found that the Venus flytrap module of both human T1R2 and T1R3 are needed for membrane trafficking, suggesting that the coexpression of human T1R2 and T1R3 is required for this event. These results suggest that the Venus flytrap module and CRD receive taste substances and play roles in membrane trafficking of human T1R2 and T1R3. These features are different from those of mouse receptors, indicating that human T1R2 and T1R3 are likely to have a novel membrane trafficking system.

  18. [The interrelation between the secretory function of the bovine udder and the amount of prolactin receptors on the membranes of the milk fat globules during lactogenesis].

    Science.gov (United States)

    Larina, M M; Tumanova, E B; Popova, A A

    1995-07-01

    The prolactin receptors number reaches its maximal level in proestrus. The data obtained suggest a correlation between high-affinity prolactin receptors concentration on the milk fat globule membranes during proestrus and the cow milk yield. The membranes may provide a model for assessing the functional state and secretory activity of the cow mammary gland.

  19. Dynamic heterogeneity and non-Gaussian statistics for acetylcholine receptors on live cell membrane

    Science.gov (United States)

    He, W.; Song, H.; Su, Y.; Geng, L.; Ackerson, B. J.; Peng, H. B.; Tong, P.

    2016-05-01

    The Brownian motion of molecules at thermal equilibrium usually has a finite correlation time and will eventually be randomized after a long delay time, so that their displacement follows the Gaussian statistics. This is true even when the molecules have experienced a complex environment with a finite correlation time. Here, we report that the lateral motion of the acetylcholine receptors on live muscle cell membranes does not follow the Gaussian statistics for normal Brownian diffusion. From a careful analysis of a large volume of the protein trajectories obtained over a wide range of sampling rates and long durations, we find that the normalized histogram of the protein displacements shows an exponential tail, which is robust and universal for cells under different conditions. The experiment indicates that the observed non-Gaussian statistics and dynamic heterogeneity are inherently linked to the slow-active remodelling of the underlying cortical actin network.

  20. Effect of chronic psychogenic stress on characteristics of some rat brain synaptic membrane receptors

    International Nuclear Information System (INIS)

    Nikuradze, V.O.; Kozlovskaya, M.M.; Rozhanets, V.V.; Val'dman, A.V.

    1986-01-01

    This paper studies characteristics of alpha- and beta-adrenoreceptors, and imipramine and bensodiazepine receptors in brain synaptic membranes of rats after exposure to combined stress for 15 days by a modified Hecht's method. Before the experiment the suspension was thawed and centrifuged. Specific binding of tritium-WB-4101 (30 Ci/mmole), tritium-dihydroalprenolol, tritium-flunitrazepam, and tritium-imipramine was carried out by known methods with certain modifications. The results suggest that pathology of behavior in rats observed in the model may be classed as a depressive-like state rather than a neurosis-like state, and the model itself may be more appropriate for the study of the mechanisms of action of compounds with marked tranquilizing activity

  1. Effect of chronic psychogenic stress on characteristics of some rat brain synaptic membrane receptors

    Energy Technology Data Exchange (ETDEWEB)

    Nikuradze, V.O.; Kozlovskaya, M.M.; Rozhanets, V.V.; Val' dman, A.V.

    1986-02-01

    This paper studies characteristics of alpha- and beta-adrenoreceptors, and imipramine and bensodiazepine receptors in brain synaptic membranes of rats after exposure to combined stress for 15 days by a modified Hecht's method. Before the experiment the suspension was thawed and centrifuged. Specific binding of tritium-WB-4101 (30 Ci/mmole), tritium-dihydroalprenolol, tritium-flunitrazepam, and tritium-imipramine was carried out by known methods with certain modifications. The results suggest that pathology of behavior in rats observed in the model may be classed as a depressive-like state rather than a neurosis-like state, and the model itself may be more appropriate for the study of the mechanisms of action of compounds with marked tranquilizing activity.

  2. Proteomics of plasma membranes from poplar trees reveals tissue distribution of transporters, receptors, and proteins in cell wall formation.

    Science.gov (United States)

    Nilsson, Robert; Bernfur, Katja; Gustavsson, Niklas; Bygdell, Joakim; Wingsle, Gunnar; Larsson, Christer

    2010-02-01

    By exploiting the abundant tissues available from Populus trees, 3-4 m high, we have been able to isolate plasma membranes of high purity from leaves, xylem, and cambium/phloem at a time (4 weeks after bud break) when photosynthesis in the leaves and wood formation in the xylem should have reached a steady state. More than 40% of the 956 proteins identified were found in the plasma membranes of all three tissues and may be classified as "housekeeping" proteins, a typical example being P-type H(+)-ATPases. Among the 213 proteins predicted to be integral membrane proteins, transporters constitute the largest class (41%) followed by receptors (14%) and proteins involved in cell wall and carbohydrate metabolism (8%) and membrane trafficking (8%). ATP-binding cassette transporters (all members of subfamilies B, C, and G) and receptor-like kinases (four subfamilies) were two of the largest protein families found, and the members of these two families showed pronounced tissue distribution. Leaf plasma membranes were characterized by a very high proportion of transporters, constituting almost half of the integral proteins. Proteins involved in cell wall synthesis (such as cellulose and sucrose synthases) and membrane trafficking were most abundant in xylem plasma membranes in agreement with the role of the xylem in wood formation. Twenty-five integral proteins and 83 soluble proteins were exclusively found in xylem plasma membranes, which identifies new candidates associated with cell wall synthesis and wood formation. Among the proteins uniquely found in xylem plasma membranes were most of the enzymes involved in lignin biosynthesis, which suggests that they may exist as a complex linked to the plasma membrane.

  3. Quantitative measurement of cell membrane receptor internalization by the nanoluciferase reporter: Using the G protein-coupled receptor RXFP3 as a model.

    Science.gov (United States)

    Liu, Yu; Song, Ge; Shao, Xiao-Xia; Liu, Ya-Li; Guo, Zhan-Yun

    2015-02-01

    Nanoluciferase (NanoLuc) is a newly developed small luciferase reporter with the brightest bioluminescence to date. In the present work, we developed NanoLuc as a sensitive bioluminescent reporter to measure quantitatively the internalization of cell membrane receptors, based on the pH dependence of the reporter activity. The G protein-coupled receptor RXFP3, the cognate receptor of relaxin-3/INSL7, was used as a model receptor. We first generated stable HEK293T cells that inducibly coexpressed a C-terminally NanoLuc-tagged human RXFP3 and a C-terminally enhanced green fluorescent protein (EGFP)-tagged human RXFP3. The C-terminal EGFP-tag and NanoLuc-tag had no detrimental effects on the ligand-binding potency and intracellular trafficking of RXFP3. Based on the fluorescence of the tagged EGFP reporter, the ligand-induced RXFP3 internalization was visualized directly under a fluorescence microscope. Based on the bioluminescence of the tagged NanoLuc reporter, the ligand-induced RXFP3 internalization was measured quantitatively by a convenient bioluminescent assay. Coexpression of an EGFP-tagged inactive [E141R]RXFP3 had no detrimental effect on the ligand-binding potency and ligand-induced internalization of the NanoLuc-tagged wild-type RXFP3, suggesting that the mutant RXFP3 and wild-type RXFP3 worked independently. The present bioluminescent internalization assay could be extended to other G protein-coupled receptors and other cell membrane receptors to study ligand-receptor and receptor-receptor interactions. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Functional activation of G-proteins coupled with muscarinic acetylcholine receptors in rat brain membranes.

    Science.gov (United States)

    Odagaki, Yuji; Kinoshita, Masakazu; Toyoshima, Ryoichi

    2014-01-01

    The functional activation of Gi/o proteins coupled to muscarinic acetylcholine receptors (mAChRs) was investigated with the conventional guanosine-5'-O-(3-[(35)S]thio) triphosphate ([(35)S]GTPγS) binding assay in rat brain membranes. The most efficacious stimulation elicited by acetylcholine or carbachol (CCh) was obtained in striatal membranes. The pharmacological properties of mAChR-mediated [(35)S]GTPγS binding determined with a series of muscarinic agonists and antagonists were almost identical among the three brain regions investigated, i.e., cerebral cortex, hippocampus, and striatum, except for the apparent partial agonist effects of (αR)-α-cyclopentyl-α-hydroxy-N-[1-(4-methyl-3-pentenyl)-4-piperidinyl]benzeneacetamide fumarate (J 104129) observed only in the hippocampus, but not in the other two regions. Among the muscarinic toxins investigated, only MT3 attenuated CCh-stimulated [(35)S] GTPγS binding. The highly selective allosteric potentiator at the M4 mAChR subtype, 3-amino-N-[(4-chlorophenyl)methyl]-4,6-dimethylthieno[2,3-b]pyridine-2-carboxamide (VU 10010), shifted the concentration-response curve for CCh leftwards as well as upwards. On the other hand, neither thiochrome nor brucine N-oxide was effective. The increases induced by CCh and 5-HT were essentially additive, though not completely, indicating that the mAChRs and 5-HT1A receptors were coupled independently to distinct pools of Gi/o proteins. Collectively, all of the data suggest that functional activation of Gi/o proteins coupled to mAChRs, especially the M4 subtype, is detectable by means of CCh-stimulated [(35)S]GTPγS binding assay in rat discrete brain regions.

  5. Inhibitory effect of progesterone on cervical tissue formation in a three-dimensional culture system with human cervical fibroblasts.

    Science.gov (United States)

    House, Michael; Tadesse-Telila, Serkalem; Norwitz, Errol R; Socrate, Simona; Kaplan, David L

    2014-01-01

    Progesterone supplementation is recommended to prevent preterm birth in women with a short cervix, but the mechanism is unclear. We hypothesize that progesterone acts by altering the composition of the cervical extracellular matrix (ECM). We tested this hypothesis using human cervical fibroblasts in both two-dimensional (2D) and three-dimensional (3D) cultures. For 2D culture, cells were seeded in 6-well plates and cultured with media supplemented with estradiol (10(-8) M), progesterone (10(-7) or 10(-6) M), and vehicle. For 3D culture, the cells were cultured on a porous silk protein scaffold system. Progesterone and estrogen receptors were documented by immunohistochemistry and Western blot analysis. In both 2D and 3D cultures, decreased collagen synthesis was seen with increased progesterone concentration. Three-dimensional cultures could be maintained significantly longer than 2D cultures, and the morphology of 3D cultures appeared similar to native cervical tissue. Thus, further studies were performed in 3D culture. To determine the effect of progesterone concentration, the 3D scaffolds were cultured with estradiol (10(-8) M) and five conditions: vehicle; 10(-9), 10(-8), or 10(-7) M progesterone; or 10(-7) M progesterone plus 10(-6) M mifepristone. The highest progesterone concentration correlated with the least amount of collagen synthesis. Collagen synthesis progressively increased as progesterone concentration decreased. This effect was partially antagonized by mifepristone, suggesting the mechanism is mediated by the progesterone receptor. This hormonally responsive 3D culture system supports the hypothesis that progesterone has a direct effect on remodeling cervical ECM during pregnancy. The 3D culture system could be useful for studying the mechanism of progesterone effects on the cervix.

  6. Inhibitory Effect of Progesterone on Cervical Tissue Formation in a Three-Dimensional Culture System with Human Cervical Fibroblasts1

    Science.gov (United States)

    House, Michael; Tadesse-Telila, Serkalem; Norwitz, Errol R.; Socrate, Simona; Kaplan, David L.

    2013-01-01

    ABSTRACT Progesterone supplementation is recommended to prevent preterm birth in women with a short cervix, but the mechanism is unclear. We hypothesize that progesterone acts by altering the composition of the cervical extracellular matrix (ECM). We tested this hypothesis using human cervical fibroblasts in both two-dimensional (2D) and three-dimensional (3D) cultures. For 2D culture, cells were seeded in 6-well plates and cultured with media supplemented with estradiol (10−8 M), progesterone (10−7 or 10−6 M), and vehicle. For 3D culture, the cells were cultured on a porous silk protein scaffold system. Progesterone and estrogen receptors were documented by immunohistochemistry and Western blot analysis. In both 2D and 3D cultures, decreased collagen synthesis was seen with increased progesterone concentration. Three-dimensional cultures could be maintained significantly longer than 2D cultures, and the morphology of 3D cultures appeared similar to native cervical tissue. Thus, further studies were performed in 3D culture. To determine the effect of progesterone concentration, the 3D scaffolds were cultured with estradiol (10−8 M) and five conditions: vehicle; 10−9, 10−8, or 10−7 M progesterone; or 10−7 M progesterone plus 10−6 M mifepristone. The highest progesterone concentration correlated with the least amount of collagen synthesis. Collagen synthesis progressively increased as progesterone concentration decreased. This effect was partially antagonized by mifepristone, suggesting the mechanism is mediated by the progesterone receptor. This hormonally responsive 3D culture system supports the hypothesis that progesterone has a direct effect on remodeling cervical ECM during pregnancy. The 3D culture system could be useful for studying the mechanism of progesterone effects on the cervix. PMID:24285720

  7. Progesterone is essential for protecting against LPS-induced pregnancy loss. LIF as a potential mediator of the anti-inflammatory effect of progesterone.

    Directory of Open Access Journals (Sweden)

    Julieta Aisemberg

    Full Text Available Lipopolysaccharide (LPS administration to mice on day 7 of gestation led to 100% embryonic resorption after 24 h. In this model, nitric oxide is fundamental for the resorption process. Progesterone may be responsible, at least in part, for a Th2 switch in the feto-maternal interface, inducing active immune tolerance against fetal antigens. Th2 cells promote the development of T cells, producing leukemia inhibitory factor (LIF, which seems to be important due to its immunomodulatory action during early pregnancy. Our aim was to evaluate the involvement of progesterone in the mechanism of LPS-induced embryonic resorption, and whether LIF can mediate hormonal action. Using in vivo and in vitro models, we provide evidence that circulating progesterone is an important component of the process by which infection causes embryonic resorption in mice. Also, LIF seems to be a mediator of the progesterone effect under inflammatory conditions. We found that serum progesterone fell to very low levels after 24 h of LPS exposure. Moreover, progesterone supplementation prevented embryonic resorption and LPS-induced increase of uterine nitric oxide levels in vivo. Results show that LPS diminished the expression of the nuclear progesterone receptor in the uterus after 6 and 12 h of treatment. We investigated the expression of LIF in uterine tissue from pregnant mice and found that progesterone up-regulates LIF mRNA expression in vitro. We observed that LIF was able to modulate the levels of nitric oxide induced by LPS in vitro, suggesting that it could be a potential mediator of the inflammatory action of progesterone. Our observations support the view that progesterone plays a critical role in a successful pregnancy as an anti-inflammatory agent, and that it could have possible therapeutic applications in the prevention of early reproductive failure associated with inflammatory disorders.

  8. Glucocorticoid receptor localizes to adherens junctions at the plasma membrane of keratinocytes.

    Directory of Open Access Journals (Sweden)

    Olivera Stojadinovic

    Full Text Available Glucocorticoids are important regulators of epidermal tissue homeostasis. As such, their clinical applications are widespread, ranging from inflammatory skin disorders to keloids and cancer. Glucocorticoids exert their effect by binding to glucocorticoid receptor (GR which translocates to the nucleus and regulates gene expression (genomic effect. In addition, GR has rapid non- genomic effects that are mediated by cell signaling proteins and do not involve gene transcription. Although genomic effects of GR in the epidermis are well documented, the non-genomic effects are not completely understood. Therefore, we utilized immunostaining and immunoprecipitations to determine specific localization of the GR in human keratinocytes that may contribute to non-genomic effects of glucocorticoid action. Here we describe a novel finding of GR localization to the plasma membrane of keratinocytes. Immunocytochemistry showed co-localization of GR with α-catenin. Immunoprecipitation of the membranous fraction revealed an association of GR with α-catenin, confirming its localization to adherens junctions. We conclude that GR localization to adherens junctions of keratinocytes provides a new mechanism of non-genomic signaling by glucocorticoids which may have significant biological and clinical impact.

  9. Free fatty acids and esters can be immobilized by receptor rich membranes from torpedo marmorata but not phospholipid acyl chains

    NARCIS (Netherlands)

    Rousselet, A.; Devaux, P.F.; Wirtz, K.W.A.

    1979-01-01

    A long chain spin labeled fatty acid and the corresponding ester have been introduced into receptor rich membranes from Torpedo Marmorata. Superimposed to a mobile component, typical of the lipid phase, a strongly immobilized component is seen on the ESR spectra, both at low temperature (−4°C) and

  10. Ruthenium complexes with phenylterpyridine derivatives target cell membrane and trigger death receptors-mediated apoptosis in cancer cells.

    Science.gov (United States)

    Deng, Zhiqin; Gao, Pan; Yu, Lianling; Ma, Bin; You, Yuanyuan; Chan, Leung; Mei, Chaoming; Chen, Tianfeng

    2017-06-01

    Elucidation of the communication between metal complexes and cell membrane may provide useful information for rational design of metal-based anticancer drugs. Herein we synthesized a novel class of ruthenium (Ru) complexes containing phtpy derivatives (phtpy = phenylterpyridine), analyzed their structure-activity relationship and revealed their action mechanisms. The result showed that, the increase in the planarity of hydrophobic Ru complexes significantly enhanced their lipophilicity and cellular uptake. Meanwhile, the introduction of nitro group effectively improved their anticancer efficacy. Further mechanism studies revealed that, complex (2c), firstly accumulated on cell membrane and interacted with death receptors to activate extrinsic apoptosis signaling pathway. The complex was then transported into cell cytoplasm through transferrin receptor-mediated endocytosis. Most of the intracellular 2c accumulated in cell plasma, decreasing the level of cellular ROS, inducing the activation of caspase-9 and thus intensifying the apoptosis. At the same time, the residual 2c can translocate into cell nucleus to interact with DNA, induce DNA damage, activate p53 pathway and enhance apoptosis. Comparing with cisplatin, 2c possesses prolonged circulation time in blood, comparable antitumor ability and importantly, much lower toxicity in vivo. Taken together, this study uncovers the role of membrane receptors in the anticancer actions of Ru complexes, and provides fundamental information for rational design of membrane receptor targeting anticancer drugs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Liquid anion exchangers (LAE) as novel receptors for plutonium pertraction across polymer immobilized liquid membranes

    International Nuclear Information System (INIS)

    Sonawane, J.V.; Anil Kumar; Sawant, S.R.; Singh, R.K.; Bajpai, D.D.; Shukla, J.P.

    1999-03-01

    The diffusion-limited and amine-facilitated Pu 4+ cation permeation in nitric acid media across a polymer immobilized liquid membrane (PILM) has been investigated to quantify the membrane carrier type effects on its transport. Primene JM-T (JMT) as primary, Amberlite LA-2 (Amb LA-2) as secondary, trilaurylamine (TLA] and triiso-octyl amine (TIOA) as tertiary and Adogen-464 (Ado-464) and Aliquat-336 (Ali-336) as quaternary amines as typical examples of nitrogen containing basic extractants are tested as the carriers. After suitable dilutions, the receptors are immobilized on a microporous polymeric support which are held within the pores by capillary forces. Both the composition of the organic membrane solvents and type of amine carriers exert a marked effect on plutonium permeation. Recovery of Pu steadily increases from primary to quaternary amines; its permeability across PILM roughly follows the order quaternary > tertiary > secondary > primary, similar to that generally observed in liquid-liquid distribution experiments. More than 95% pertraction of Pu(IV) is easily accomplished using tertiary or quaternary amine as ionophores across PILM in single run employing a feed solution containing about 5 mg dm -3 Pu in 4 M nitric acid solution while the receiving phase is 0.1M NH 2 OH.HCl prepared in 0.3M HNO 3 . On the other hand, plutonium permeation at 4M HNO 3 under similar experimental conditions using other types of amines as carriers namely primary amine, Pri JM-T afforded only 19% and 49% by Amb LA-2 in 6-7h runs. Results of the detailed study to evaluate the effect of other contaminants on Pu transport are also discussed. (author)

  12. Structure-based drug design targeting the cell membrane receptor GPBAR1: exploiting the bile acid scaffold towards selective agonism

    Science.gov (United States)

    di Leva, Francesco Saverio; Festa, Carmen; Renga, Barbara; Sepe, Valentina; Novellino, Ettore; Fiorucci, Stefano; Zampella, Angela; Limongelli, Vittorio

    2015-11-01

    Bile acids can regulate nutrient metabolism through the activation of the cell membrane receptor GPBAR1 and the nuclear receptor FXR. Developing an exogenous control over these receptors represents an attractive strategy for the treatment of enterohepatic and metabolic disorders. A number of dual GPBAR1/FXR agonists are known, however their therapeutic use is limited by multiple unwanted effects due to activation of the diverse downstream signals controlled by the two receptors. On the other hand, designing selective GPBAR1 and FXR agonists is challenging since the two proteins share similar structural requisites for ligand binding. Here, taking advantage of our knowledge of the two targets, we have identified through a rational drug design study a series of amine lithocholic acid derivatives as selective GPBAR1 agonists. The presence of the 3α-NH2 group on the steroidal scaffold is responsible for the selectivity over FXR unveiling unprecedented structural insights into bile acid receptors activity modulation.

  13. Improved localization of cellular membrane receptors using combined fluorescence microscopy and simultaneous topography and recognition imaging

    Energy Technology Data Exchange (ETDEWEB)

    Duman, M; Pfleger, M; Chtcheglova, L A; Neundlinger, I; Bozna, B L; Ebner, A; Schuetz, G J; Hinterdorfer, P [Institute for Biophysics, University of Linz, Altenbergerstrasse 69, A-4040 Linz (Austria); Zhu, R; Mayer, B [Christian Doppler Laboratory for Nanoscopic Methods in Biophysics, Institute for Biophysics, University of Linz, Altenbergerstrasse 69, A-4040 Linz (Austria); Rankl, C; Moertelmaier, M; Kada, G; Kienberger, F [Agilent Technologies Austria GmbH, Aubrunnerweg 11, A-4040 Linz (Austria); Salio, M; Shepherd, D; Polzella, P; Cerundolo, V [Cancer Research UK Tumor Immunology Group, Weatherall Institute of Molecular Medicine, Nuffield Department of Medicine, University of Oxford, Oxford OX3 9DS (United Kingdom); Dieudonne, M, E-mail: ferry_kienberger@agilent.com [Agilent Technologies Belgium, Wingepark 51, Rotselaar, AN B-3110 (Belgium)

    2010-03-19

    The combination of fluorescence microscopy and atomic force microscopy has a great potential in single-molecule-detection applications, overcoming many of the limitations coming from each individual technique. Here we present a new platform of combined fluorescence and simultaneous topography and recognition imaging (TREC) for improved localization of cellular receptors. Green fluorescent protein (GFP) labeled human sodium-glucose cotransporter (hSGLT1) expressed Chinese Hamster Ovary (CHO) cells and endothelial cells (MyEnd) from mouse myocardium stained with phalloidin-rhodamine were used as cell systems to study AFM topography and fluorescence microscopy on the same surface area. Topographical AFM images revealed membrane features such as lamellipodia, cytoskeleton fibers, F-actin filaments and small globular structures with heights ranging from 20 to 30 nm. Combined fluorescence and TREC imaging was applied to detect density, distribution and localization of YFP-labeled CD1d molecules on {alpha}-galactosylceramide ({alpha}GalCer)-loaded THP1 cells. While the expression level, distribution and localization of CD1d molecules on THP1 cells were detected with fluorescence microscopy, the nanoscale distribution of binding sites was investigated with molecular recognition imaging by using a chemically modified AFM tip. Using TREC on the inverted light microscope, the recognition sites of cell receptors were detected in recognition images with domain sizes ranging from {approx} 25 to {approx} 160 nm, with the smaller domains corresponding to a single CD1d molecule.

  14. [3H]opipramol labels a novel binding site and sigma receptors in rat brain membranes

    International Nuclear Information System (INIS)

    Ferris, C.D.; Hirsch, D.J.; Brooks, B.P.; Snowman, A.M.; Snyder, S.H.

    1991-01-01

    Opipramol (OP), a clinically effective antidepressant with a tricyclic structure, is inactive as an inhibitor of biogenic amine uptake. [ 3 H]Opipramol binds saturably to rat brain membranes (apparent KD = 4 nM, Bmax = 3 pmol/mg of protein). [ 3 H]Opipramol binding can be differentiated into haloperidol-sensitive and -resistant components, with Ki values for haloperidol of 1 nM (Bmax = 1 pmol/mg of protein) and 350 nM (Bmax = 1.9 pmol/mg of protein), respectively. The drug specificity of the haloperidol-sensitive component is the same as that of sigma receptors labeled with (+)-[ 3 H]3-(3-hydroxyphenyl)-N-(1-propyl)piperdine. The haloperidol-resistant component does not correspond to any known neurotransmitter receptor or uptake recognition site. It displays high affinity for phenothiazines and related structures such as perphenazine, clopenthixol, and flupenthixol, whose potencies are comparable to that of opipramol. Because certain of these drugs are more potent at the haloperidol-resistant opipramol site than in exerting any other action, it is possible that this opipramol-selective site may mediate their therapeutic effects

  15. Neuroprotective effects of 17β-estradiol rely on estrogen receptor membrane initiated signals

    Directory of Open Access Journals (Sweden)

    Marco eFiocchetti

    2012-04-01

    Full Text Available 17β-estradiol (E2 exerts protective effects in the central nervous system besides its crucial role in many physiological and pathological events. E2 effects are not restricted to the brain areas related with the control of the reproductive function, but rather are widespread throughout the developing and the adult brain. E2 actions are mediated by estrogen receptors (i.e., ERα and ERβ belonging to the nuclear receptor super family. As members of the ligand-regulated transcription factor family, the actions of ERs in the brain were thought to mediate only the E2 long-term transcriptional effects. However, a growing body of evidence has emerged indicating the presence of rapid, membrane initiated E2 effects in the brain which result independent from ER transcriptional activities and involved in E2-induced neuroprotection. Aim of this review is to focus on the rapid effects of E2 in the brain taking into account the specific contribution of the signaling pathway of ERβ subtype in neuroprotective actions of E2.

  16. Activation of the B cell receptor leads to increased membrane proximity of the Igα cytoplasmic domain.

    Directory of Open Access Journals (Sweden)

    Wing-Yiu Lee

    Full Text Available Binding of antigen to the B cell receptor (BCR induces conformational changes in BCR's cytoplasmic domains that are concomitant with phosphorylation of the immunoreceptor tyrosine-based activation motifs (ITAMs. Recently, reversible folding of the CD3ε and ξ chain ITAMs into the plasma membrane has been suggested to regulate T cell receptor signaling. Here we show that the Igα and Igβ cytoplasmic domains of the BCR do not associate with plasma membrane in resting B cells. However, antigen binding and ITAM phosphorylation specifically increased membrane proximity of Igα, but not Igβ. Thus, BCR activation is accompanied by asymmetric conformational changes, possibly promoting the binding of Igα and Igβ to differently localized signaling complexes.

  17. Binding equilibrium and kinetics of membrane-anchored receptors and ligands in cell adhesion: Insights from computational model systems and theory

    Science.gov (United States)

    Weikl, Thomas R.; Hu, Jinglei; Xu, Guang-Kui; Lipowsky, Reinhard

    2016-01-01

    ABSTRACT The adhesion of cell membranes is mediated by the binding of membrane-anchored receptor and ligand proteins. In this article, we review recent results from simulations and theory that lead to novel insights on how the binding equilibrium and kinetics of these proteins is affected by the membranes and by the membrane anchoring and molecular properties of the proteins. Simulations and theory both indicate that the binding equilibrium constant K2D and the on- and off-rate constants of anchored receptors and ligands in their 2-dimensional (2D) membrane environment strongly depend on the membrane roughness from thermally excited shape fluctuations on nanoscales. Recent theory corroborated by simulations provides a general relation between K2D and the binding constant K3D of soluble variants of the receptors and ligands that lack the membrane anchors and are free to diffuse in 3 dimensions (3D). PMID:27294442

  18. Application of comparative genomics in the identification and analysis of novel families of membrane-associated receptors in bacteria

    Directory of Open Access Journals (Sweden)

    Aravind L

    2003-08-01

    Full Text Available Abstract Background A great diversity of multi-pass membrane receptors, typically with 7 transmembrane (TM helices, is observed in the eukaryote crown group. So far, they are relatively rare in the prokaryotes, and are restricted to the well-characterized sensory rhodopsins of various phototropic prokaryotes. Results Utilizing the currently available wealth of prokaryotic genomic sequences, we set up a computational screen to identify putative 7 (TM and other multi-pass membrane receptors in prokaryotes. As a result of this procedure we were able to recover two widespread families of 7 TM receptors in bacteria that are distantly related to the eukaryotic 7 TM receptors and prokaryotic rhodopsins. Using sequence profile analysis, we were able to establish that the first members of these receptor families contain one of two distinct N-terminal extracellular globular domains, which are predicted to bind ligands such as carbohydrates. In their intracellular portions they contain fusions to a variety of signaling domains, which suggest that they are likely to transduce signals via cyclic AMP, cyclic diguanylate, histidine phosphorylation, dephosphorylation, and through direct interactions with DNA. The second family of bacterial 7 TM receptors possesses an α-helical extracellular domain, and is predicted to transduce a signal via an intracellular HD hydrolase domain. Based on comparative analysis of gene neighborhoods, this receptor is predicted to function as a regulator of the diacylglycerol-kinase-dependent glycerolipid pathway. Additionally, our procedure also recovered other types of putative prokaryotic multi-pass membrane associated receptor domains. Of these, we characterized two widespread, evolutionarily mobile multi-TM domains that are fused to a variety of C-terminal intracellular signaling domains. One of these typified by the Gram-positive LytS protein is predicted to be a potential sensor of murein derivatives, whereas the other one

  19. Immunohistochemical evaluation of oestrogen receptors α and β in epithelium of the vaginal mucous membrane in women after oestrogen therapy

    Directory of Open Access Journals (Sweden)

    Beata Sawczuk

    2017-04-01

    Full Text Available Oestrogens act on target cells through α and β receptors (ERα and ERβ. Expression of oestrogen receptors is associated with the age and menopausal condition of women. The aim of the study was an immunohistochemical evaluation of ERα and ERβ receptors in epithelium of the vaginal mucous membrane of women subjected to different forms of hormonal therapy (HTM. Oestrogen receptors ERα and ERβ were identified using immunohistochemical methods and evaluated in smears of vaginal mucous membranes collected from 60 patients subjected to HTM (including 20 patients after oral therapy, 20 patients after transdermal therapy, and 20 patients after vaginal therapy. The results showed a significant change in immunoreactivity of both studied receptors after three months of hormone therapy. The biggest differences in the changes of intensity of ERα and ERβ reactions were observed in patients subjected to vaginal therapy. Immunostaining for α receptor showed differences between three types of hormone therapy. The highest increase in the overall intensity occurred after three months of topical therapy. Immunostaining for Erβ also varied for different types of hormone therapy. The results indicate that hormone therapy administered vaginally is the most effective in the treatment of urogenital ailments during menopause. In addition, topical therapy eliminates adverse effects of systemic oestrogen.

  20. Progesterone Receptor Scaffolding Function in Breast Cancer

    Science.gov (United States)

    2011-10-01

    Radioisotope concentrator gene therapy for cancer with the sodium/iodide symporter gene. American Society of Gene Therapy , Second Annual Meeting...REPORT DATE: October 2011 TYPE OF REPORT: Annual Summary PREPARED FOR: U.S. Army Medical Research and Materiel Command...MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) U.S. Army Medical Research and Materiel Command Fort Detrick, Maryland

  1. Eps15 is recruited to the plasma membrane upon epidermal growth factor receptor activation and localizes to components of the endocytic pathway during receptor internalization

    DEFF Research Database (Denmark)

    Torrisi, M R; Lotti, L V; Belleudi, F

    1999-01-01

    role for eps15 in receptor-mediated endocytosis. In this study we show that, upon activation of the EGFR kinase, eps15 undergoes dramatic relocalization consisting of 1) initial relocalization to the plasma membrane and 2) subsequent colocalization with the EGFR in various intracellular compartments......Eps15 is a substrate for the tyrosine kinase of the epidermal growth factor receptor (EGFR) and is characterized by the presence of a novel protein:protein interaction domain, the EH domain. Eps15 also stably binds the clathrin adaptor protein complex AP-2. Previous work demonstrated an essential......, suggesting sustained phosphorylation in endocytic compartments. Our results are consistent with a model in which eps15 undergoes cycles of association:dissociation with membranes and suggest multiple roles for this protein in the endocytic pathway....

  2. Expression and functional characterization of membrane-integrated mammalian corticotropin releasing factor receptors 1 and 2 in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Roberto Jappelli

    Full Text Available Corticotropin-Releasing Factor Receptors (CRFRs are class B1 G-protein-coupled receptors, which bind peptides of the corticotropin releasing factor family and are key mediators in the stress response. In order to dissect the receptors' binding specificity and enable structural studies, full-length human CRFR1α and mouse CRFR2β as well as fragments lacking the N-terminal extracellular domain, were overproduced in E. coli. The characteristics of different CRFR2β-PhoA gene fusion products expressed in bacteria were found to be in agreement with the predicted ones in the hepta-helical membrane topology model. Recombinant histidine-tagged CRFR1α and CRFR2β expression levels and bacterial subcellular localization were evaluated by cell fractionation and Western blot analysis. Protein expression parameters were assessed, including the influence of E. coli bacterial hosts, culture media and the impact of either PelB or DsbA signal peptide. In general, the large majority of receptor proteins became inserted in the bacterial membrane. Across all experimental conditions significantly more CRFR2β product was obtained in comparison to CRFR1α. Following a detergent screen analysis, bacterial membranes containing CRFR1α and CRFR2β were best solubilized with the zwitterionic detergent FC-14. Binding of different peptide ligands to CRFR1α and CRFR2β membrane fractions were similar, in part, to the complex pharmacology observed in eukaryotic cells. We suggest that our E. coli expression system producing functional CRFRs will be useful for large-scale expression of these receptors for structural studies.

  3. Image Restoration and Analysis of Influenza Virions Binding to Membrane Receptors Reveal Adhesion-Strengthening Kinetics.

    Directory of Open Access Journals (Sweden)

    Donald W Lee

    Full Text Available With the development of single-particle tracking (SPT microscopy and host membrane mimics called supported lipid bilayers (SLBs, stochastic virus-membrane binding interactions can be studied in depth while maintaining control over host receptor type and concentration. However, several experimental design challenges and quantitative image analysis limitations prevent the widespread use of this approach. One main challenge of SPT studies is the low signal-to-noise ratio of SPT videos, which is sometimes inevitable due to small particle sizes, low quantum yield of fluorescent dyes, and photobleaching. These situations could render current particle tracking software to yield biased binding kinetic data caused by intermittent tracking error. Hence, we developed an effective image restoration algorithm for SPT applications called STAWASP that reveals particles with a signal-to-noise ratio of 2.2 while preserving particle features. We tested our improvements to the SPT binding assay experiment and imaging procedures by monitoring X31 influenza virus binding to α2,3 sialic acid glycolipids. Our interests lie in how slight changes to the peripheral oligosaccharide structures can affect the binding rate and residence times of viruses. We were able to detect viruses binding weakly to a glycolipid called GM3, which was undetected via assays such as surface plasmon resonance. The binding rate was around 28 folds higher when the virus bound to a different glycolipid called GD1a, which has a sialic acid group extending further away from the bilayer surface than GM3. The improved imaging allowed us to obtain binding residence time distributions that reflect an adhesion-strengthening mechanism via multivalent bonds. We empirically fitted these distributions using a time-dependent unbinding rate parameter, koff, which diverges from standard treatment of koff as a constant. We further explain how to convert these models to fit ensemble-averaged binding data

  4. Membrane cholesterol effect on the 5-HT2A receptor: Insights into the lipid-induced modulation of an antipsychotic drug target.

    Science.gov (United States)

    Ramírez-Anguita, Juan Manuel; Rodríguez-Espigares, Ismael; Guixà-González, Ramon; Bruno, Agostino; Torrens-Fontanals, Mariona; Varela-Rial, Alejandro; Selent, Jana

    2018-01-01

    The serotonin 5-hydroxytryptamine 2A (5-HT 2A ) receptor is a G-protein-coupled receptor (GPCR) relevant for the treatment of CNS disorders. In this regard, neuronal membrane composition in the brain plays a crucial role in the modulation of the receptor functioning. Since cholesterol is an essential component of neuronal membranes, we have studied its effect on the 5-HT 2A receptor dynamics through all-atom MD simulations. We find that the presence of cholesterol in the membrane increases receptor conformational variability in most receptor segments. Importantly, detailed structural analysis indicates that conformational variability goes along with the destabilization of hydrogen bonding networks not only within the receptor but also between receptor and lipids. In addition to increased conformational variability, we also find receptor segments with reduced variability. Our analysis suggests that this increased stabilization is the result of stabilizing effects of tightly bound cholesterol molecules to the receptor surface. Our finding contributes to a better understanding of membrane-induced alterations of receptor dynamics and points to cholesterol-induced stabilizing and destabilizing effects on the conformational variability of GPCRs. © 2017 International Union of Biochemistry and Molecular Biology, Inc.

  5. Circulating TNF receptors are significant prognostic biomarkers for idiopathic membranous nephropathy.

    Directory of Open Access Journals (Sweden)

    Su Mi Lee

    Full Text Available Idiopathic membranous nephropathy (iMN is a common cause of nephrotic syndrome in adults. A biomarker to accurately indicate the severity of iMN and predict long-term prognosis is insufficient. Here, we evaluated the clinical significance of circulating tumor necrosis factor receptors (cTNFRs as prognostic biomarkers of iMN with nephrotic syndrome. A total of 113 patients with biopsy-proven iMN and 43 healthy volunteers were enrolled in this study. Ninety patients with iMN had nephrotic range proteinuria. Levels of cTNFRs were measured by using serum samples collected at the time of initial diagnosis. Levels of cTNFRs were higher in the patients with nephrotic syndrome than in those with subnephrotic range proteinuria or in the healthy volunteers (P for trend <0.001. Estimated glomerular filtration rate and proteinuria tended to worsen as the cTNFRs levels increased. Having a cTNFR1 level within the highest tertile was a significant risk factor for renal progression after adjustment, in comparison with the other tertiles (hazard ratio [HR], 3.39; 95% confidence interval [95% CI], 1.48-7.78; P = 0.004. The cTNFR2 level within the highest tertile also significantly increased the risk of renal progression (HR, 3.29; 95% CI, 1.43-7.54; P = 0.005. Renal tubular TNFRs expression was associated with cTNFRs level. However, the cTNFRs levels were not associated with autoantibody against phospholipase A2 receptor reactivity/levels or treatment response. This study demonstrated that cTNFRs levels at the time of initial diagnosis could predict renal progression in patients with iMN.

  6. Synaptic NMDA Receptor-Dependent Ca2+ Entry Drives Membrane Potential and Ca2+ Oscillations in Spinal Ventral Horn Neurons

    Science.gov (United States)

    Alpert, Michael H.; Alford, Simon

    2013-01-01

    During vertebrate locomotion, spinal neurons act as oscillators when initiated by glutamate release from descending systems. Activation of NMDA receptors initiates Ca2+-mediated intrinsic membrane potential oscillations in central pattern generator (CPG) neurons. NMDA receptor-dependent intrinsic oscillations require Ca2+-dependent K+ (KCa2) channels for burst termination. However, the location of Ca2+ entry mediating KCa2 channel activation, and type of Ca2+ channel – which includes NMDA receptors and voltage-gated Ca2+ channels (VGCCs) – remains elusive. NMDA receptor-dependent Ca2+ entry necessitates presynaptic release of glutamate, implying a location at active synapses within dendrites, whereas VGCC-dependent Ca2+ entry is not similarly constrained. Where Ca2+ enters relative to KCa2 channels is crucial to information processing of synaptic inputs necessary to coordinate locomotion. We demonstrate that Ca2+ permeating NMDA receptors is the dominant source of Ca2+ during NMDA-dependent oscillations in lamprey spinal neurons. This Ca2+ entry is synaptically located, NMDA receptor-dependent, and sufficient to activate KCa2 channels at excitatory interneuron synapses onto other CPG neurons. Selective blockade of VGCCs reduces whole-cell Ca2+ entry but leaves membrane potential and Ca2+ oscillations unaffected. Furthermore, repetitive oscillations are prevented by fast, but not slow, Ca2+ chelation. Taken together, these results demonstrate that KCa2 channels are closely located to NMDA receptor-dependent Ca2+ entry. The close spatial relationship between NMDA receptors and KCa2 channels provides an intrinsic mechanism whereby synaptic excitation both excites and subsequently inhibits ventral horn neurons of the spinal motor system. This places the components necessary for oscillation generation, and hence locomotion, at glutamatergic synapses. PMID:23646190

  7. Triple-color super-resolution imaging of live cells: resolving submicroscopic receptor organization in the plasma membrane.

    Science.gov (United States)

    Wilmes, Stephan; Staufenbiel, Markus; Lisse, Domenik; Richter, Christian P; Beutel, Oliver; Busch, Karin B; Hess, Samuel T; Piehler, Jacob

    2012-05-14

    In living color: efficient intracellular covalent labeling of proteins with a photoswitchable dye using the HaloTag for dSTORM super-resolution imaging in live cells is described. The dynamics of cellular nanostructures at the plasma membrane were monitored with a time resolution of a few seconds. In combination with dual-color FPALM imaging, submicroscopic receptor organization within the context of the membrane skeleton was resolved. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. OVULATORY RESFONSE IN PROGESTERONE SYNCHRONIZED ...

    African Journals Online (AJOL)

    Conception rate and ovarian function following estrus control by progestetone injections in dairy cattle. J. Anim. Sci. 14, 224. VAN NIEKERK, C.H., BELONJE, P.C. & SPREETH, E.B., 1970. Post partum synchronization of the oestrus period of lactating friesland cows with 6-methyl-17-acetozy-Progesterone. (MAP) and PMSG.

  9. Inhalation of progesterone inhibits chronic airway inflammation of mice exposed to ozone.

    Science.gov (United States)

    Fei, Xia; Bao, Wuping; Zhang, Pengyu; Zhang, Xue; Zhang, Guoqing; Zhang, Yingying; Zhou, Xin; Zhang, Min

    2017-05-01

    Chronic ozone exposure leads to a model of mice with lung inflammation, emphysema and oxidative stress. Progesterone plays an important role in attenuating the neuroinflammation. We assume that progesterone will reduce the chronic airway inflammation exposed to ozone and evaluate whether combination of progesterone with glucocorticoids results in synergistic effects. C57/BL6 mice were exposed to ozone (2.5ppm, 3h) 12 times over 6 weeks, and were administered with progesterone (0.03 or 0.3mg/L; inhaled) alone or combined with budesonide (BUD) (0.2g/L) after each exposure until the tenth week. Mice were studied 24h after final exposure, cells and inflammatory mediators were assessed in bronchoalveolar lavage fluid (BALF) and lungs used for evaluation of glucocorticoids receptors (GR), p38 mitogen-activated protein kinase (MAPK) phosphorylation and nuclear transcription factor κB (NF-κB) activation. Exposure to ozone resulted in a marked lung neutrophilia. Moreover, in ozone-exposed group, the levels of oxidative stress-related interleukin (IL)-1β, IL-6, IL-8, IL-17A, activated NF-κB and p38MAPK, airway inflammatory cells infiltration density, mean linear intercept (Lm) were greatly increased, FEV 25 and glucocorticoids receptors (GR) were markedly decreased. Comparable to BUD, progesterone treatment dose-dependently led to a significant reduction of IL-1β, IL-6, IL-8, IL-17A, activated NF-κB and p38MAPK, and an increase of FEV 25 and GR. Progesterone combined with BUD resulted in dramatic changes, compared to monotherapy of BUD or progesterone. Therefore, these results demonstrate that chronic ozone exposure has profound airway inflammatory effects counteracted by progesterone and progesterone acts synergistically with glucocorticoids in attenuating the airway inflammation dose-dependently. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. [Effect of damage integrity rat brain synaptic membranes on the functional activity GABA(A)-receptor/Cl(-)-ionophore complex in the CNC].

    Science.gov (United States)

    Rebrov, I G; Kalinina, M V

    2013-01-01

    Functional activity of the CGABA(A)-receptor/Cl(-) ionophore complex was investigated the muscimol-stimulated entry of the radioactive isotope 36Cl(-) in synaptoneurosomes in changing the structure and permeability of neuronal membranes. Integrity of the membranes was damaged by removal of Ca(+2) and Mg(+2) from the incubation medium and by the method of freezing-thawing synaptoneurosomes. In both cases, an increase in basal 36Cl(-) entry into synaptoneurosomes, indicating increased nonspecific permeability of neuronal membranes, and decreased activity the CABA(A)-receptor/Cl(-) ionophore complex. The conclusion about the relationship of processes damage neuronal membranes and reducing the inhibitory processes in the epileptic focus.

  11. LRRK2 affects vesicle trafficking, neurotransmitter extracellular level and membrane receptor localization.

    Directory of Open Access Journals (Sweden)

    Rossana Migheli

    Full Text Available The leucine-rich repeat kinase 2 (LRRK2 gene was found to play a role in the pathogenesis of both familial and sporadic Parkinson's disease (PD. LRRK2 encodes a large multi-domain protein that is expressed in different tissues. To date, the physiological and pathological functions of LRRK2 are not clearly defined. In this study we have explored the role of LRRK2 in controlling vesicle trafficking in different cellular or animal models and using various readouts. In neuronal cells, the presence of LRRK2(G2019S pathological mutant determines increased extracellular dopamine levels either under basal conditions or upon nicotine stimulation. Moreover, mutant LRRK2 affects the levels of dopamine receptor D1 on the membrane surface in neuronal cells or animal models. Ultrastructural analysis of PC12-derived cells expressing mutant LRRK2(G2019S shows an altered intracellular vesicle distribution. Taken together, our results point to the key role of LRRK2 to control vesicle trafficking in neuronal cells.

  12. Plasma membrane cholesterol level and agonist-induced internalization of δ-opioid receptors; colocalization study with intracellular membrane markers of Rab family.

    Science.gov (United States)

    Brejchova, Jana; Vosahlikova, Miroslava; Roubalova, Lenka; Parenti, Marco; Mauri, Mario; Chernyavskiy, Oleksandr; Svoboda, Petr

    2016-08-01

    Decrease of cholesterol level in plasma membrane of living HEK293 cells transiently expressing FLAG-δ-OR by β-cyclodextrin (β-CDX) resulted in a slight internalization of δ-OR. Massive internalization of δ-OR induced by specific agonist DADLE was diminished in cholesterol-depleted cells. These results suggest that agonist-induced internalization of δ-OR, which has been traditionally attributed exclusively to clathrin-mediated pathway, proceeds at least partially via membrane domains. Identification of internalized pools of FLAG-δ-OR by colocalization studies with proteins of Rab family indicated the decreased presence of receptors in early endosomes (Rab5), late endosomes and lysosomes (Rab7) and fast recycling vesicles (Rab4). Slow type of recycling (Rab11) was unchanged by cholesterol depletion. As expected, agonist-induced internalization of oxytocin receptors was totally suppressed in β-CDX-treated cells. Determination of average fluorescence lifetime of TMA-DPH, the polar derivative of hydrophobic membrane probe diphenylhexatriene, in live cells by FLIM indicated a significant alteration of the overall PM structure which may be interpreted as an increased "water-accessible space" within PM area. Data obtained by studies of HEK293 cells transiently expressing FLAG-δ-OR by "antibody feeding" method were extended by analysis of the effect of cholesterol depletion on distribution of FLAG-δ-OR in sucrose density gradients prepared from HEK293 cells stably expressing FLAG-δ-OR. Major part of FLAG-δ-OR was co-localized with plasma membrane marker Na,K-ATPase and β-CDX treatment resulted in shift of PM fragments containing both FLAG-δ-OR and Na,K-ATPase to higher density. Thus, the decrease in content of the major lipid constituent of PM resulted in increased density of resulting PM fragments.

  13. Differential expression of growth factor receptors and membrane-bound tumor markers for imaging in male and female breast cancer.

    Directory of Open Access Journals (Sweden)

    Jeroen F Vermeulen

    Full Text Available INTRODUCTION: Male breast cancer accounts for 0.5-1% of all breast cancers and is generally diagnosed at higher stage than female breast cancers and therefore might benefit from earlier detection and targeted therapy. Except for HER2 and EGFR, little is known about expression of growth factor receptors in male breast cancer. We therefore investigated expression profiles of growth factor receptors and membrane-bound tumor markers in male breast cancer and gynecomastia, in comparison with female breast cancer. METHODS: Tissue microarrays containing 133 male breast cancer and 32 gynecomastia cases were stained by immunohistochemistry for a panel of membrane-bound targets and compared with data on 266 female breast cancers. RESULTS: Growth factor receptors were variably expressed in 4.5% (MET up to 38.5% (IGF1-R of male breast cancers. Compared to female breast cancer, IGF1-R and carbonic anhydrase 12 (CAXII were more frequently and CD44v6, MET and FGFR2 less frequently expressed in male breast cancer. Expression of EGFR, HER2, CAIX, and GLUT1 was not significantly different between male and female breast cancer. Further, 48.1% of male breast cancers expressed at least one and 18.0% expressed multiple growth factor receptors. Since individual membrane receptors are expressed in only half of male breast cancers, a panel of membrane markers will be required for molecular imaging strategies to reach sensitivity. A potential panel of markers for molecular imaging, consisting of EGFR, IGF1-R, FGFR2, CD44v6, CAXII, GLUT1, and CD44v6 was positive in 77% of male breast cancers, comparable to female breast cancers. CONCLUSIONS: Expression patterns of growth factor receptors and hypoxia membrane proteins in male breast cancer are different from female breast cancer. For molecular imaging strategies, a putative panel consisting of markers for EGFR, IGF1-R, FGFR2, GLUT1, CAXII, CD44v6 was positive in 77% of cases and might be considered for development of

  14. Membrane Microdomains and Cytoskeleton Organization Shape and Regulate the IL-7 Receptor Signalosome in Human CD4 T-cells*

    Science.gov (United States)

    Tamarit, Blanche; Bugault, Florence; Pillet, Anne-Hélène; Lavergne, Vincent; Bochet, Pascal; Garin, Nathalie; Schwarz, Ulf; Thèze, Jacques; Rose, Thierry

    2013-01-01

    Interleukin (IL)-7 is the main homeostatic regulator of CD4 T-lymphocytes (helper) at both central and peripheral levels. Upon activation by IL-7, several signaling pathways, mainly JAK/STAT, PI3K/Akt and MAPK, induce the expression of genes involved in T-cell differentiation, activation, and proliferation. We have analyzed the early events of CD4 T-cell activation by IL-7. We have shown that IL-7 in the first few min induces the formation of cholesterol-enriched membrane microdomains that compartmentalize its activated receptor and initiate its anchoring to the cytoskeleton, supporting the formation of the signaling complex, the signalosome, on the IL-7 receptor cytoplasmic domains. Here we describe by stimulated emission depletion microscopy the key roles played by membrane microdomains and cytoskeleton transient organization in the IL-7-regulated JAK/STAT signaling pathway. We image phospho-STAT5 and cytoskeleton components along IL-7 activation kinetics using appropriate inhibitors. We show that lipid raft inhibitors delay and reduce IL-7-induced JAK1 and JAK3 phosphorylation. Drug-induced disassembly of the cytoskeleton inhibits phospho-STAT5 formation, transport, and translocation into the nucleus that controls the transcription of genes involved in T-cell activation and proliferation. We fit together the results of these quantitative analyses and propose the following mechanism. Activated IL-7 receptors embedded in membrane microdomains induce actin-microfilament meshwork formation, anchoring microtubules that grow radially from rafted receptors to the nuclear membrane. STAT5 phosphorylated by signalosomes are loaded on kinesins and glide along the microtubules across the cytoplasm to reach the nucleus 2 min after IL-7 stimulation. Radial microtubules disappear 15 min later, while transversal microtubules, independent of phospho-STAT5 transport, begin to bud from the microtubule organization center. PMID:23329834

  15. Analysis of functional damages of membrane receptor by radiation exposure and development of the damage preventive method by modifying the membrane lipids

    Energy Technology Data Exchange (ETDEWEB)

    Amano, Fumio; Tanaka, Yasuhito; Asano, Toshihiko; Ogura, Atsuro; Suzuki, Osamu; Matsuda, Junichiro [National Inst. of Health, Tokyo (Japan)

    1997-02-01

    The influences of radiation exposure on the body were evaluated with ligand-binding ability of a receptor on biomembrane, which is a highly sensitive and essential indicator for human body. The present study aimed to establish a model system for ligand-receptor binding reactions and analyze the effects of {gamma}-ray radiation on the systems. When a macrophage cell line RAW 264.7 was exposed to {gamma}-ray, active oxygen (O{sub 2}{sup -}) producing capacity was significantly increased when compared to non-exposed cells at a dose ranging 1.3-2.6 Gy but decreased at 5.3 Gy or more, whereas the producing ability of nitrogen monoxide radical was not affected by the radiation. Then, radiation effects on cell surface receptor was examined using a monocyte cell line, U937. The distributions of CD14 and CD4 were not changed by radiation, but the TNF{alpha} receptor was increased dose-dependently. When the membrane lipids were modified by using bovine serum albumin bound eicosapentaenoic acid (BSA-EPA), the increase of TNF{alpha} expression caused by radiation did not occur, while the expression was decreased when modified with BSA bound arachidonic acid (BSA-AA). (M.N.)

  16. Roles of specific membrane lipid domains in EGF receptor activation and cell adhesion molecule stabilization in a developing olfactory system.

    Science.gov (United States)

    Gibson, Nicholas J; Tolbert, Leslie P; Oland, Lynne A

    2009-09-29

    Reciprocal interactions between glial cells and olfactory receptor neurons (ORNs) cause ORN axons entering the brain to sort, to fasciculate into bundles destined for specific glomeruli, and to form stable protoglomeruli in the developing olfactory system of an experimentally advantageous animal species, the moth Manduca sexta. Epidermal growth factor receptors (EGFRs) and the cell adhesion molecules (IgCAMs) neuroglian and fasciclin II are known to be important players in these processes. We report in situ and cell-culture studies that suggest a role for glycosphingolipid-rich membrane subdomains in neuron-glia interactions. Disruption of these subdomains by the use of methyl-beta-cyclodextrin results in loss of EGFR activation, depletion of fasciclin II in ORN axons, and loss of neuroglian stabilization in the membrane. At the cellular level, disruption leads to aberrant ORN axon trajectories, small antennal lobes, abnormal arrays of olfactory glomerul, and loss of normal glial cell migration. We propose that glycosphingolipid-rich membrane subdomains (possible membrane rafts or platforms) are essential for IgCAM-mediated EGFR activation and for anchoring of neuroglian to the cytoskeleton, both required for normal extension and sorting of ORN axons.

  17. Sodium modulates opioid receptors through a membrane component different from G-proteins. Demonstration by target size analysis

    International Nuclear Information System (INIS)

    Ott, S.; Costa, T.; Herz, A.

    1988-01-01

    The target size for opioid receptor binding was studied after manipulations known to affect the interactions between receptor and GTP-binding regulatory proteins (G-proteins). Addition of GTP or its analogs to the binding reaction, exposure of intact cells to pertussis toxin prior to irradiation, or treatment of irradiated membranes with N-ethylmaleimide did not change the target size (approximately equal to 100 kDa) for opioid receptors in NG 108-15 cells and rat brain. These data suggest that the 100-kDa species does not include an active subunit of a G-protein or alternatively that GTP does not promote the dissociation of the receptor-G-protein complex. The presence of Na+ (100 mM) in the radioligand binding assay induced a biphasic decay curve for agonist binding and a flattening of the monoexponential decay curve for a partial agonist. In both cases the effect was explained by an irradiation-induced loss of the low affinity state of the opioid receptor produced by the addition of Na+. This suggests that an allosteric inhibitor that mediates the effect of sodium on the receptor is destroyed at low doses of irradiation, leaving receptors which are no longer regulated by sodium. The effect of Na+ on target size was slightly increased by the simultaneous addition of GTP but was not altered by pertussis toxin treatment. Thus, the sodium unit is distinct from G-proteins and may represent a new component of the opioid receptor complex. Assuming a simple bimolecular model of one Na+ unit/receptor, the size of this inhibitor can be measured as 168 kDa

  18. Cross-linking of endothelin 1 and endothelin 3 to rat brain membranes: Identification of the putative receptor

    Energy Technology Data Exchange (ETDEWEB)

    Ambar, I.; Kloog, Y.; Sokolovsky, M. (Tel Aviv Univ. (Israel))

    1990-07-10

    Affinity-labeling experiments with {sup 125}I-endothelin derivatives using bifunctional cross-lining reagents were carried out in an attempt to identify the polypeptide component(s) of the endothelin/sarafotoxin receptors in rat brain tissues. In rat cerebellum, cortex, and caudate putamen, endothelin 1 specifically labeled a major component with a molecular mass of around 53,000. In the same tissues endothelin 3 specifically labeled, in addition to the 53,000 band, a band of molecular mass of 38,000. This result clearly indicates that in the brain the endothelin binding site resides within a polypeptide of apparent M{sub r} = 53,000. The possible presence of receptor subtypes is discussed with reference also to the reported identification of endothelin receptors in chick cardiac membrane and in rat mesangial cells.

  19. Receptores de estrógeno e progesterona em células do sedimento de fluido peritoneal na endometriose pélvica: estudo imunocitoquímico Estrogen and progesterone receptors in peritoneal fluid cell sediment in pelvic endometriosis: immunocytochemical study

    Directory of Open Access Journals (Sweden)

    José Eleutério Junior

    2001-03-01

    Full Text Available Objetivo: avaliar a expressão de receptores de estrógeno (RE e progesterona (RP em esfregaços de sedimento de fluido peritoneal em pacientes com endometriose, comparando-a com a de mulheres sem endometriose. Métodos: foi realizado imunocitoquímica para RE e RP em esfregaços de sedimento de fluido peritoneal em 19 casos de endometriose e 7 sem endometriose (controle. Os dados foram submetidos ao teste t de Student para análise estatística. Resultados: em 84,6% dos casos de pacientes com endometriose, células tipo endometrial expressaram RE, numa média de 4,1%, ao passo que nos casos sem endometriose foi positivo em 42,9%, com uma expressão média de 4,5% (p = 0,1706. RP foi expresso apenas em um caso, com endometriose, com história de rotura de endometrioma. Conclusões: não houve diferença da expressão de RE entre os casos de endometriose e os casos-controle, observando-se um comportamento distinto em tecidos. Um mais aprofundado estudo deve ser feito para melhor avaliar o enigmático mecanismo envolvido na manifestação de receptores hormonais em células esfoliadas.Purpose: to evaluate the expression of estrogen (ER and progesterone (PR receptors in smears of peritoneal fluid sediment from patients with and without endometriosis. Methods: immunocytochemical study of ER and PR in smears of peritoneal fluid sediment in 19 cases with endometriosis and 7 without (control group, observing their expression. The data were submitted to Student's t-test to evaluate statistical significance. Results: in 84.6% of the cases with endometriosis, endometrial-like cells expressed ER (mean = 4.1%. In cases without endometriosis there was ER expression in 42.9%, with a mean of 4.5% (p = 0.1706. PR was expressed in only one case of endometriosis, with an endometrioma rupture history. Conclusions: there was no difference of ER expression between cases with endometriosis and the control group, in contrast to tissue behavior. Further cases must be

  20. Estrogen and progesterone stimulate Schwann cell proliferation in a sex- and age-dependent manner

    DEFF Research Database (Denmark)

    Svenningsen, Åsa Fex; Kanje, M

    1999-01-01

    The effects of estrogen and progesterone on Schwann cell proliferation were studied in cultured segments of the rat sciatic nerve from adult male, female, and newborn rats, by measurement of [3H thymidine incorporation or bromo-deoxy-uridine- (BrdU)-labelling and immunocytochemistry. Estrogen (100...... for estrogen and progesterone and that these receptors may be involved in the control of Schwann cell proliferation. It also shows that the response of Schwann cells to sex hormones varies with sex and perhaps also with age....... in Schwann cells from male rats at high concentrations. The proliferative effects of estrogen and progesterone were blocked when the segments were cultured in the presence of inhibitors of their respective receptors, ICI 128 780 and zk 112994. The data suggest that Schwann cells possess distinct receptors...

  1. Distribution of interleukin-1 receptor complex at the synaptic membrane driven by interleukin-1β and NMDA stimulation.

    Science.gov (United States)

    Gardoni, Fabrizio; Boraso, Mariaserena; Zianni, Elisa; Corsini, Emanuela; Galli, Corrado L; Cattabeni, Flaminio; Marinovich, Marina; Di Luca, Monica; Viviani, Barbara

    2011-02-11

    Interleukin-1β (IL-1β) is a pro-inflammatory cytokine that contributes to neuronal injury in various degenerative diseases, and is therefore a potential therapeutic target. It exerts its biological effect by activating the interleukin-1 receptor type I (IL-1RI) and recruiting a signalling core complex consisting of the myeloid differentiation primary response protein 88 (MyD88) and the IL-1R accessory protein (IL-1RAcP). This pathway has been clearly described in the peripheral immune system, but only scattered information is available concerning the molecular composition and distribution of its members in neuronal cells. The findings of this study show that IL-1RI and its accessory proteins MyD88 and IL-1RAcP are differently distributed in the hippocampus and in the subcellular compartments of primary hippocampal neurons. In particular, only IL-1RI is enriched at synaptic sites, where it co-localises with, and binds to the GluN2B subunit of NMDA receptors. Furthermore, treatment with NMDA increases IL-1RI interaction with NMDA receptors, as well as the surface expression and localization of IL-1RI at synaptic membranes. IL-1β also increases IL-1RI levels at synaptic sites, without affecting the total amount of the receptor in the plasma membrane. Our results reveal for the first time the existence of a dynamic and functional interaction between NMDA receptor and IL-1RI systems that could provide a molecular basis for IL-1β as a neuromodulator in physiological and pathological events relying on NMDA receptor activation.

  2. Survival analysis according to the receiver tumoral expression profile of the epidermal growth factor - 2 (HER2), the estrogen receptor (ER) and progesterone receptor (RP) in Uruguayan patients with breast cancer

    International Nuclear Information System (INIS)

    Camejo, N.; Gonzalez, V.; Ferrero, L.; Castillo, C.; Delgado, L.; Fresco, R.; Santander, G.; Aguiar, S.; Heinzen, S.; Martinez, A.; Maurizt, S.; Meyer, C.; Sena, G.; Spera, G.; Ubillos, L.; Xavier, F.; Deneo, H.; Aghazarian, M.; Rodriguez, R.; Sabini, G.

    2010-01-01

    Breast cancer (CM), the leading cause of death from cancer in Uruguayan women, is a heterogeneous disease. The study of the expression level of tumor hormone receptor (H R) and Her-2 neu can recognize subtypes with different characteristics. We have previously reported the relationship of these with the clinico pathological features. To analyze the PFS (SVLP) as the biological subtype (patients HR + / HER2 - triple negative (TN) and HER2 +) in Uruguayan patients with breast cancer EI-IIII Methodology: A retrospective study where SVLP 169 cancer patients carrying analyzed breast E I-III, diagnosed between March 2006 and March 2008 from the Clinical Hospital, Military Hospital, INCA and CASMU. SVLP analysis was performed according to different biological subtypes using the Kaplan method Meier and statistical significance of differences was assessed by the log-rank test. Results: The median follow-up was 43 months. At the time of analysis 160 patients (94.7%) are alive and 141 (83.4%) are relapse-free. One hundred twenty-three patients were HR + / HER2 - (72.7%), 32 patients were TN (18.9%) and 14 were HER2 + patients (8.2%). The SVLP to two years for the total of patients was 92.3%, 94% for HR + / HER2 - 91% for TN and 71.4% for HER2 +. Comparing the curves for different subtypes SVLP showed lower for SVLP He r2 + patients compared to patients HR + / HER2 - (p = 0.03) and TN (p 0.11). The median survival was not reached globally or in the subgroup analysis. Conclusions: He r2 + patients have a shorter time to relapse which coincides as reported in the literature. SVLP similar to 2 years and overlapping of curves SVLP Patients HR + / HER2 - and TN not be explained by differences in characteristics clinico pathological

  3. Transcriptional response of the murine mammary gland to acute progesterone exposure.

    Science.gov (United States)

    Fernandez-Valdivia, Rodrigo; Mukherjee, Atish; Creighton, Chad J; Buser, Adam C; DeMayo, Francesco J; Edwards, Dean P; Lydon, John P

    2008-12-01

    Our mechanistic understanding of progesterone's involvement in murine mammary morphogenesis and tumorigenesis is dependent on defining effector pathways responsible for transducing the progesterone signal into a morphogenetic response. Toward this goal, microarray methods were applied to the murine mammary gland to identify novel downstream gene targets of progesterone. Consistent with a tissue undergoing epithelial expansion, mining of the progesterone-responsive transcriptome revealed the up-regulation of functional gene classes involved in epithelial proliferation and survival. Reassuringly, signaling pathways previously reported to be responsive to progesterone were also identified. Mining this informational resource for rapidly induced genes, we identified "inhibitor of differentiation 4" (Id4) as a new molecular target acutely induced by progesterone exposure. Mammary Id4 is transiently induced during early pregnancy and colocalizes with progesterone receptor (PR) expression, suggesting that Id4 mediates the early events of PR-dependent mammary morphogenesis. Chromatin immunoprecipitation assay detecting direct recruitment of ligand occupied PR to the Id4 promoter supports this proposal. Given that Id4 is a member of the Id family of transcriptional regulators that have been linked to the maintenance of proliferative status and tumorigenesis, the establishment of a mechanistic link between PR signaling and Id4 promises to furnish a wider conceptual framework with which to advance our understanding of normal and abnormal mammary epithelial responses to progestins. In sum, the progesterone-responsive transcriptome described herein not only reinforces the importance of progesterone in mammary epithelial expansion but also represents an invaluable information resource with which to identify novel signaling paradigms for mammary PR action.

  4. REEPs are membrane shaping adapter proteins that modulate specific g protein-coupled receptor trafficking by affecting ER cargo capacity.

    Directory of Open Access Journals (Sweden)

    Susann Björk

    Full Text Available Receptor expression enhancing proteins (REEPs were identified by their ability to enhance cell surface expression of a subset of G protein-coupled receptors (GPCRs, specifically GPCRs that have proven difficult to express in heterologous cell systems. Further analysis revealed that they belong to the Yip (Ypt-interacting protein family and that some REEP subtypes affect ER structure. Yip family comparisons have established other potential roles for REEPs, including regulation of ER-Golgi transport and processing/neuronal localization of cargo proteins. However, these other potential REEP functions and the mechanism by which they selectively enhance GPCR cell surface expression have not been clarified. By utilizing several REEP family members (REEP1, REEP2, and REEP6 and model GPCRs (α2A and α2C adrenergic receptors, we examined REEP regulation of GPCR plasma membrane expression, intracellular processing, and trafficking. Using a combination of immunolocalization and biochemical methods, we demonstrated that this REEP subset is localized primarily to ER, but not plasma membranes. Single cell analysis demonstrated that these REEPs do not specifically enhance surface expression of all GPCRs, but affect ER cargo capacity of specific GPCRs and thus their surface expression. REEP co-expression with α2 adrenergic receptors (ARs revealed that this REEP subset interacts with and alter glycosidic processing of α2C, but not α2A ARs, demonstrating selective interaction with cargo proteins. Specifically, these REEPs enhanced expression of and interacted with minimally/non-glycosylated forms of α2C ARs. Most importantly, expression of a mutant REEP1 allele (hereditary spastic paraplegia SPG31 lacking the carboxyl terminus led to loss of this interaction. Thus specific REEP isoforms have additional intracellular functions besides altering ER structure, such as enhancing ER cargo capacity, regulating ER-Golgi processing, and interacting with select cargo

  5. TGF-α/HA complex promotes tympanic membrane keratinocyte migration and proliferation via ErbB1 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Mei Teh, Bing, E-mail: bing.teh@earscience.org.au [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head, Neck and Skull Base Surgery, Sir Charles Gairdner Hospital, Nedlands, WA (Australia); Redmond, Sharon L. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Shen, Yi [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head and Neck, Ningbo Lihuili Hospital (Ningbo Medical Centre), Ningbo, Zhejiang (China); Atlas, Marcus D. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head, Neck and Skull Base Surgery, Sir Charles Gairdner Hospital, Nedlands, WA (Australia); Marano, Robert J.; Dilley, Rodney J. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia)

    2013-04-01

    Tympanic membrane perforations are common and represent a management challenge to clinicians. Current treatments for chronic perforations involve a graft surgery and require general anaesthesia, including associated costs and morbidities. Bioactive molecules (e.g. growth factors, cytokines) play an important role in promoting TM wound healing following perforation and the use of growth factors as a topical treatment for tympanic membrane perforations has been suggested as an alternative to surgery. However, the choice of bioactive molecules best suited to promote wound healing has yet to be identified. We investigated the effects of hyaluronic acid, vitronectin, TGF-α, IL-24 and their combinations on migration, proliferation and adhesion of cultured human tympanic membrane-derived keratinocytes (hTM), in addition to their possible mechanisms of action. We found that TGF-α, TGF-α/HA and TGF-α/IL-24 promoted wound healing by significantly increasing both migration and proliferation. TGF-α and/or HA treated cells showed comparable cell–cell adhesion whilst maintaining an epithelial cell phenotype. With the use of receptor binding inhibitors for ErbB1 (AG1478) and CD44 (BRIC235), we revealed that the activation of ErbB1 is required for TGF-α/HA-mediated migration and proliferation. These results suggest factors that may be incorporated into a tissue-engineered membrane or directly as topical treatment for tympanic membrane perforations and hence reduce the need for a surgery. - Highlights: ► TGF-α, TGF-α/HA and TGF-α/IL-24 improved hTM keratinocyte migration and proliferation. ► TGF-α and/or HA maintained epithelial cell phenotype. ► TGF-α/HA-mediated migration and proliferation requires activation of ErbB1 receptor.

  6. Type-1 cannabinoid receptors reduce membrane fluidity of capacitated boar sperm by impairing their activation by bicarbonate.

    Directory of Open Access Journals (Sweden)

    Barbara Barboni

    Full Text Available BACKGROUND: Mammalian spermatozoa acquire their full fertilizing ability (so called capacitation within the female genital tract, where they are progressively exposed to inverse gradients of inhibiting and stimulating molecules. METHODOLOGY/PRINCIPAL FINDINGS: In the present research, the effect on this process of anandamide, an endocannabinoid that can either activate or inhibit cannabinoid receptors depending on its concentration, and bicarbonate, an oviductal activatory molecule, was assessed, in order to study the role exerted by the type 1 cannabinoid receptor (CB1R in the process of lipid membrane remodeling crucial to complete capacitation. To this aim, boar sperm were incubated in vitro under capacitating conditions (stimulated by bicarbonate in the presence or in the absence of methanandamide (Met-AEA, a non-hydrolysable analogue of anandamide. The CB1R involvement was studied by using the specific inhibitor (SR141716 or mimicking its activation by adding a permeable cAMP analogue (8Br-cAMP. By an immunocytochemistry approach it was shown that the Met-AEA inhibits the bicarbonate-dependent translocation of CB1R from the post-equatorial to equatorial region of sperm head. In addition it was found that Met-AEA is able to prevent the bicarbonate-induced increase in membrane disorder and the cholesterol extraction, both preliminary to capacitation, acting through a CB1R-cAMP mediated pathway, as indicated by MC540 and filipin staining, EPR spectroscopy and biochemical analysis on whole membranes (CB1R activity and on membrane enriched fraction (C/P content and anisotropy. CONCLUSIONS/SIGNIFICANCE: Altogether, these data demonstrate that the endocannabinoid system strongly inhibits the process of sperm capacitation, acting as membrane stabilizing agent, thus increasing the basic knowledge on capacitation-related signaling and potentially opening new perspectives in diagnostics and therapeutics of male infertility.

  7. Nuclear and Membrane Actions of Estrogen Receptor Alpha: Contribution to the Regulation of Energy and Glucose Homeostasis.

    Science.gov (United States)

    Guillaume, Maeva; Montagner, Alexandra; Fontaine, Coralie; Lenfant, Françoise; Arnal, Jean-François; Gourdy, Pierre

    2017-01-01

    Estrogen receptor alpha (ERα) has been demonstrated to play a key role in reproduction but also to exert numerous functions in nonreproductive tissues. Accordingly, ERα is now recognized as a key regulator of energy homeostasis and glucose metabolism and mediates the protective effects of estrogens against obesity and type 2 diabetes. This chapter attempts to summarize our current understanding of the mechanisms of ERα activation and their involvement in the modulation of energy balance and glucose metabolism. We first focus on the experimental studies that constitute the basis of the understanding of ERα as a nuclear receptor and more specifically on the key roles played by its two activation functions (AFs). We depict the consequences of the selective inactivation of these AFs in mouse models, which further underline the prominent role of nuclear ERα in the prevention of obesity and diabetes, as on the reproductive tract and the vascular system. Besides these nuclear actions, a fraction of ERα is associated with the plasma membrane and activates nonnuclear signaling from this site. Such rapid effects, called membrane-initiated steroid signals (MISS), have been characterized in a variety of cell lines and in particular in endothelial cells. The development of selective pharmacological tools that specifically activate MISS as well as the generation of mice expressing an ERα protein impeded for membrane localization has just begun to unravel the physiological role of MISS in vivo and their contribution to ERα-mediated metabolic protection. Finally, we discuss novel perspectives for the design of tissue-selective ER modulators.

  8. Structures of the signal recognition particle receptor from the archaeon Pyrococcus furiosus: implications for the targeting step at the membrane.

    Science.gov (United States)

    Egea, Pascal F; Tsuruta, Hiro; de Leon, Gladys P; Napetschnig, Johanna; Walter, Peter; Stroud, Robert M

    2008-01-01

    In all organisms, a ribonucleoprotein called the signal recognition particle (SRP) and its receptor (SR) target nascent proteins from the ribosome to the translocon for secretion or membrane insertion. We present the first X-ray structures of an archeal FtsY, the receptor from the hyper-thermophile Pyrococcus furiosus (Pfu), in its free and GDP*magnesium-bound forms. The highly charged N-terminal domain of Pfu-FtsY is distinguished by a long N-terminal helix. The basic charges on the surface of this helix are likely to regulate interactions at the membrane. A peripheral GDP bound near a regulatory motif could indicate a site of interaction between the receptor and ribosomal or SRP RNAs. Small angle X-ray scattering and analytical ultracentrifugation indicate that the crystal structure of Pfu-FtsY correlates well with the average conformation in solution. Based on previous structures of two sub-complexes, we propose a model of the core of archeal and eukaryotic SRP*SR targeting complexes.

  9. Structures of the Signal Recognition Particle Receptor From the Archaeon Pyrococcus Furiosus: Implications for the Targeting Step at the Membrane

    Energy Technology Data Exchange (ETDEWEB)

    Egea, P.F.; Tsuruta, H.; Leon, G.P.de; Napetschnig, J.; Walter, P.; Stroud, R.M.

    2009-05-18

    In all organisms, a ribonucleoprotein called the signal recognition particle (SRP) and its receptor (SR) target nascent proteins from the ribosome to the translocon for secretion or membrane insertion. We present the first X-ray structures of an archeal FtsY, the receptor from the hyper-thermophile Pyrococcus furiosus (Pfu), in its free and GDP {center_dot} magnesium-bound forms. The highly charged N-terminal domain of Pfu-FtsY is distinguished by a long N-terminal helix. The basic charges on the surface of this helix are likely to regulate interactions at the membrane. A peripheral GDP bound near a regulatory motif could indicate a site of interaction between the receptor and ribosomal or SRP RNAs. Small angle X-ray scattering and analytical ultracentrifugation indicate that the crystal structure of Pfu-FtsY correlates well with the average conformation in solution. Based on previous structures of two sub-complexes, we propose a model of the core of archeal and eukaryotic SRP {center_dot} SR targeting complexes.

  10. [GSM 1,800 MHz radiofrequency electromagnetic fields induced clustering of membrane surface receptors and interference by noise magnetic fields].

    Science.gov (United States)

    Xie, Liang; jiang, Huai; Sun, Wen-jun; Fu, Yi-ti; Lu, De-qiang

    2006-08-01

    To investigate the possible effect of exposure to GSM 1,800 MHz radiofrequency electromagnetic fields (RF EMF) on epidermal growth factor (EGF) receptor and its possible interference by noise magnetic fields (MF). Chinese hamster lung fibroblasts (CHL) were exposed to 1,800 MHz RF EMF (modulated by 217 Hz or 50 Hz, or unmodulated), 2 microT noise MF, and RF EMF combined with 2 microT noise MF for 15 min, respectively. The specific absorption rates (SARs) of RF EMF were 0.1, 0.5, 1.0, 2.0 and 4.0 W/kg. Commercial EGF (1 ng/ml) treatment was used as positive control. EGF receptors on the cell membrane were observed under a laser scanning confocal microscope after indirect immunofluorescence staining. EGF receptor clustering was induced after exposure to GSM 1,800 MHz RF EMF modulated by 217 Hz or 50 Hz MF at SARs of 0.5, 1.0, 2.0, 4.0 W/kg for 15 min as induced by 1 ng/ml EGF, but not at SAR of 0.1 W/kg. And no EGF receptor clustering was found in cells after exposure to unmodulated RF EMF or 2 microT noise MF. In addition, superposition of 2 microT noise MF could inhibit the EGF receptor clustering induced by GSM 1,800 MHz RF EMF. EGF receptor clustering in CHL cells can be induced by GSM 1,800 MHz RF EMF at the lowest SAR of 0.5 W/kg and inhibited by noise MF. The modulation of wave may play an important role in the inducement of receptor clustering after RF exposure.

  11. Feasibility of progesterone treatment for ischaemic stroke.

    Science.gov (United States)

    Gibson, Claire L; Bath, Philip M

    2016-03-01

    Two multi-centre phase III clinical trials examining the protective potential of progesterone following traumatic brain injury have recently failed to demonstrate any improvement in outcome. Thus, it is timely to consider how this impacts on the translational potential of progesterone treatment for ischaemic stroke. A wealth of experimental evidence supports the neuroprotective properties of progesterone, and associated metabolites, following various types of central nervous system injury. In particular, for ischaemic stroke, studies have also begun to reveal possible mechanisms of such neuroprotection. However, the results in traumatic brain injury now question whether further clinical development of progesterone for ischaemic stroke is relevant. © The Author(s) 2015.

  12. Functional role of the extracellular N-terminal domain of neuropeptide Y subfamily receptors in membrane integration and agonist-stimulated internalization.

    Science.gov (United States)

    Lindner, Diana; Walther, Cornelia; Tennemann, Anja; Beck-Sickinger, Annette G

    2009-01-01

    The N terminus is the most variable element in G protein-coupled receptors (GPCRs), ranging from seven residues up to approximately 5900 residues. For family B and C GPCRs it is described that at least part of the ligand binding site is located within the N terminus. Here we investigated the role of the N terminus in the neuropeptide Y receptor family, which belongs to the class A of GPCRs. We cloned differentially truncated Y receptor mutants, in which the N terminus was partially or completely deleted. We found, that eight amino acids are sufficient for full ligand binding and signal transduction activity. Interestingly, we could show that no specific amino acids but rather the extension of the first transmembrane helix by any residues is sufficient for receptor activity but also for membrane integration in case of the hY(1) and the hY(4) receptors. In contrast, the complete deletion of the N terminus in the hY(2) receptors resulted in a mutant that is fully integrated in the membrane but does not bind the ligand very well and internalizes much slower compared to the wild type receptor. Interestingly, also these effects could be reverted by any N-terminal extension. Accordingly, the most important function of the N termini seems to be the stabilization of the first transmembrane helix to ensure the correct receptor structure, which obviously is essential for ligand binding, integration into the cell membrane and receptor internalization.

  13. Membrane mineralocorticoid but not glucocorticoid receptors of the dorsal hippocampus mediate the rapid effects of corticosterone on memory retrieval.

    Science.gov (United States)

    Dorey, Rodolphe; Piérard, Christophe; Shinkaruk, Svitlana; Tronche, Christophe; Chauveau, Frédéric; Baudonnat, Mathieu; Béracochéa, Daniel

    2011-12-01

    This study was aimed at determining the type of the glucocorticoid membrane receptors (mineralocorticoid receptors (MRs) or glucocorticoid receptors (GRs)) in the dorsal hippocampus (dHPC) involved in the rapid effects of corticosterone or stress on memory retrieval. For that purpose, we synthesized corticosterone-3-O-carboxymethyloxime-bovine serum albumin conjugate (Cort-3CMO-BSA) conjugate (a high MW complex that cannot cross the cell membrane) totally devoid of free corticosterone, stable in physiological conditions. In a first experiment, we evidenced that an acute stress (electric footshocks) induced both a dHPC corticosterone rise measured by microdialysis and memory retrieval impairment on delayed alternation task. Both the endocrinal and cognitive effects of stress were blocked by metyrapone (a corticosterone synthesis inhibitor). In a second experiment, we showed that bilateral injections of either corticosterone or Cort-3CMO-BSA in dHPC 15 min before memory testing produced impairments similar to those resulting from acute stress. Furthermore, we showed that anisomycin (a protein synthesis inhibitor) failed to block the deleterious effect of Cort-3CMO-BSA on memory. In a third experiment, we evidenced that intra-hippocampal injection of RU-28318 (MR antagonist) but not of RU-38486 (GR antagonist) totally blocked the Cort-3CMO-BSA-induced memory retrieval deficit. In a fourth experiment, we demonstrated that RU-28318 administered 15 min before stress blocked the stress-induced memory impairments when behavioral testing occurred 15 min but not 60 min after stress. Overall, this study provides strong in vivo evidence that the dHPC membrane GRs, mediating the rapid and non-genomic effects of acute stress on memory retrieval, are of MR but not GR type.

  14. Molecular mechanisms of acetylcholine receptor-lipid interactions: from model membranes to human biology.

    Science.gov (United States)

    Baenziger, John E; daCosta, Corrie J B

    2013-03-01

    Lipids are potent modulators of the Torpedo nicotinic acetylcholine receptor. Lipids influence nicotinic receptor function by allosteric mechanisms, stabilizing varying proportions of pre-existing resting, open, desensitized, and uncoupled conformations. Recent structures reveal that lipids could alter function by modulating transmembrane α-helix/α-helix packing, which in turn could alter the conformation of the allosteric interface that links the agonist-binding and transmembrane pore domains-this interface is essential in the coupling of agonist binding to channel gating. We discuss potential mechanisms by which lipids stabilize different conformational states in the context of the hypothesis that lipid-nicotinic receptor interactions modulate receptor function at biological synapses.

  15. The linoleic acid derivative DCP-LA increases membrane surface localization of the α7 ACh receptor in a protein 4.1N-dependent manner.

    Science.gov (United States)

    Kanno, Takeshi; Tsuchiya, Ayako; Tanaka, Akito; Nishizaki, Tomoyuki

    2013-03-01

    In yeast two-hybrid screening, protein 4.1N, a scaffolding protein, was identified as a binding partner of the α7 ACh (acetylcholine) receptor. For rat hippocampal slices, the linoleic acid derivative DCP-LA {8-[2-(2-pentyl-cyclopropylmethyl)-cyclopropyl]-octanoic acid} increased the association of the α7 ACh receptor with 4.1N, and the effect was inhibited by GF109203X, an inhibitor of PKC (protein kinase C), although DCP-LA did not induce PKC phosphorylation of 4.1N. For PC-12 cells, the presence of the α7 ACh receptor in the plasma membrane fraction was significantly suppressed by knocking down 4.1N. DCP-LA increased the presence of the α7 ACh receptor in the plasma membrane fraction, and the effect was still inhibited by knocking down 4.1N. In the monitoring of α7 ACh receptor mobilization, DCP-LA enhanced signal intensities for the α7 ACh receptor at the membrane surface in PC-12 cells, which was clearly prevented by knocking down 4.1N. Taken together, the results of the present study show that 4.1N interacts with the α7 ACh receptor and participates in the receptor tethering to the plasma membrane. The results also indicate that DCP-LA increases membrane surface localization of the α7 ACh receptor in a 4.1N-dependent manner under the control of PKC, but without phosphorylating 4.1N.

  16. Structure of the Neisserial outer membrane protein Opa₆₀: loop flexibility essential to receptor recognition and bacterial engulfment.

    Science.gov (United States)

    Fox, Daniel A; Larsson, Per; Lo, Ryan H; Kroncke, Brett M; Kasson, Peter M; Columbus, Linda

    2014-07-16

    The structure and dynamics of Opa proteins, which we report herein, are responsible for the receptor-mediated engulfment of Neisseria gonorrheae or Neisseria meningitidis by human cells and can offer deep understanding into the molecular recognition of pathogen-host receptor interactions. Such interactions are vital to understanding bacterial pathogenesis as well as the mechanism of foreign body entry to a human cell, which may provide insights for the development of targeted pharmaceutical delivery systems. The size and dynamics of the extracellular loops of Opa60 required a hybrid refinement approach wherein membrane and distance restraints were used to generate an initial NMR structural ensemble, which was then further refined using molecular dynamics in a DMPC bilayer. The resulting ensemble revealed that the extracellular loops, which bind host receptors, occupy compact conformations, interact with each other weakly, and are dynamic on the nanosecond time scale. We predict that this conformational sampling is critical for enabling diverse Opa loop sequences to engage a common set of receptors.

  17. Amniotic membrane-derived mesenchymal cells and their conditioned media: potential candidates for uterine regenerative therapy in the horse.

    Directory of Open Access Journals (Sweden)

    Bruna Corradetti

    Full Text Available Amniotic membrane-derived mesenchymal cells (AMCs are considered suitable candidates for a variety of cell-based applications. In view of cell therapy application in uterine pathologies, we studied AMCs in comparison to cells isolated from the endometrium of mares at diestrus (EDCs being the endometrium during diestrus and early pregnancy similar from a hormonal standpoint. In particular, we demonstrated that amnion tissue fragments (AM shares the same transcriptional profile with endometrial tissue fragments (ED, expressing genes involved in early pregnancy (AbdB-like Hoxa genes, pre-implantation conceptus development (Erα, PR, PGRMC1 and mPR and their regulators (Wnt7a, Wnt4a. Soon after the isolation, only AMCs express Wnt4a and Wnt7a. Interestingly, the expression levels of prostaglandin-endoperoxide synthase 2 (PTGS2 were found greater in AM and AMCs than their endometrial counterparts thus confirming the role of AMCs as mediators of inflammation. The expression of nuclear progesterone receptor (PR, membrane-bound intracellular progesterone receptor component 1 (PGRMC1 and membrane-bound intracellular progesterone receptor (mPR, known to lead to improved endometrial receptivity, was maintained in AMCs over 5 passages in vitro when the media was supplemented with progesterone. To further explore the potential of AMCs in endometrial regeneration, their capacity to support resident cell proliferation was assessed by co-culturing them with EDCs in a transwell system or culturing in the presence of AMC-conditioned medium (AMC-CM. A significant increase in EDC proliferation rate exhibited the crucial role of soluble factors as mediators of stem cells action. The present investigation revealed that AMCs, as well as their derived conditioned media, have the potential to improve endometrial cell replenishment when low proliferation is associated to pregnancy failure. These findings make AMCs suitable candidates for the treatment of endometrosis in

  18. The extracellular membrane-proximal domain of membrane-bound IgE restricts B cell activation by limiting B cell antigen receptor surface expression.

    Science.gov (United States)

    Vanshylla, Kanika; Opazo, Felipe; Gronke, Konrad; Wienands, Jürgen; Engels, Niklas

    2018-03-01

    Immunoglobulin E (IgE) antibodies are key mediators of allergic reactions. Due to their potentially harmful anaphylactic properties, their production is tightly regulated. The membrane-bound isoform of IgE (mIgE), which is an integral component of the B cell antigen receptor, has been shown to be critical for the regulation of IgE responses in mice. In primate species including humans, mIgE can be expressed in two isoforms that are produced by alternative splicing of the primary ε Ig heavy chain transcript, and differ in the absence or presence of an extracellular membrane-proximal domain (EMPD) consisting of 52 amino acids. However, the function of the EMPD remains unclear. Here, we demonstrate that the EMPD restricts surface expression of mIgE-containing BCRs in human and murine B cells. The EMPD does not interfere with BCR assembly but acts as an autonomous endoplasmic reticulum retention domain. Limited surface expression of EMPD-containing mIgE-BCRs caused impaired activation of intracellular signaling cascades and hence represents a regulatory mechanism that may control the production of potentially anaphylactic IgE antibodies in primate species. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. A Gata2-Dependent Transcription Network Regulates Uterine Progesterone Responsiveness and Endometrial Function

    Directory of Open Access Journals (Sweden)

    Cory A. Rubel

    2016-10-01

    Full Text Available Altered progesterone responsiveness leads to female infertility and cancer, but underlying mechanisms remain unclear. Mice with uterine-specific ablation of GATA binding protein 2 (Gata2 are infertile, showing failures in embryo implantation, endometrial decidualization, and uninhibited estrogen signaling. Gata2 deficiency results in reduced progesterone receptor (PGR expression and attenuated progesterone signaling, as evidenced by genome-wide expression profiling and chromatin immunoprecipitation. GATA2 not only occupies at and promotes expression of the Pgr gene but also regulates downstream progesterone responsive genes in conjunction with the PGR. Additionally, Gata2 knockout uteri exhibit abnormal luminal epithelia with ectopic TRP63 expressing squamous cells and a cancer-related molecular profile in a progesterone-independent manner. Lastly, we found a conserved GATA2-PGR regulatory network in both human and mice based on gene signature and path analyses using gene expression profiles of human endometrial tissues. In conclusion, uterine Gata2 regulates a key regulatory network of gene expression for progesterone signaling at the early pregnancy stage.

  20. Naturally occurring progesterone in loblolly pine (Pinus taeda L.): a major steroid precursor of environmental androgens.

    Science.gov (United States)

    Carson, John D; Jenkins, Ronald L; Wilson, Elizabeth M; Howell, W Mike; Moore, Ray

    2008-06-01

    Progesterone, androstenedione, and androstadienedione were previously identified in the water and sediment of the Fenholloway River (Taylor County, FL, USA), a river that contains populations of masculinized female mosquitofish downstream of a paper mill, at levels higher than those in the nearby Spring Creek. Plant sterols, such as beta-sitosterol in mill effluent derived from pine tree pulp, were suggested to be metabolized by bacteria to progesterone and androgens to account for the masculinization phenomenon. The current study made use of standard solid-phase methanol extraction procedures, high-performance liquid chromatography, liquid chromatography-mass spectrometry, and a cell-based, androgen-receptor transcription assay to determine naturally occurring progesterone levels in mature pine trees. Progesterone concentrations in the loblolly pine (Pinus taeda L.) were 49.34 +/- 4.1 nmol/g dry mature wood (15.5 +/- 1.29 microg/g), 12.26 +/- 1.78 nmol/g pine needles (3.85 +/- 0.56 microg/g), and 3.81 +/- 0.36 nmol/g pine bark (1.19 +/- 0.11 mug/g). The results suggest that naturally occurring progesterone from pine wood pulp contributes to increased progesterone levels downstream of paper mill effluent discharges and may serve as the natural steroid precursor for environmental androgen production that causes masculinization of female mosquitofish.

  1. Receptor kinase-mediated control of primary active proton pumping at the plasma membrane

    DEFF Research Database (Denmark)

    Fuglsang, Anja Thoe; Kristensen, Astrid; Cuin, Tracey A.

    2014-01-01

    Acidification of the cell wall space outside the plasma membrane is required for plant growth and is the result of proton extrusion by the plasma membrane-localized H+-ATPases. Here we show that the major plasma membrane proton pumps in Arabidopsis, AHA1 and AHA2, interact directly in vitro...... heterologous expression system, the introduction of a negative charge at this position caused pump activation. Application of PSY1 to plant seedlings induced rapid in planta phosphorylation at Thr-881, concomitant with an instantaneous increase in proton efflux from roots. The direct interaction between AHA2...

  2. [Progesterone and prevention of preterm birth].

    Science.gov (United States)

    Fuchs, F; Senat, M-V

    2015-10-01

    The literature confirms the interest of progesterone for prevention of preterm delivery in specific indications for patients carrying a singleton pregnancy. In contrast, randomized trials have shown no benefit using progesterone in the prevention of prematurity in twins and even an adverse effect. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  3. Milk progesterone concentrations: an accurate early pregnancy ...

    African Journals Online (AJOL)

    by milk progesterone quantitation was determined as well as the diagnostic efficiency of the test for days 14- 24 ... Progesterone was quantitated utilizing a single antibody non- extraction iodine - 125radioimmunoassay employing ... with horseradish peroxidase as tracer. The antiserum against the bovine serum albumin ...

  4. Progesterone stimulates pancreatic cell proliferation in vivo

    NARCIS (Netherlands)

    Nieuwenhuizen, AG; Schuiling, GA; Liem, SMS; Moes, H; Koiter, TR; Uilenbroek, JTJ

    Treatment of cyclic and pregnant rats with progesterone stimulates cell proliferation within the islets of Langerhans. It was investigated whether this effect of progesterone depends on sex and/or the presence of the gonads or the presence of oestradiol, For this purpose, Silastic tubes containing

  5. Progesterone and the Latency Period: Threatened Preterm Labor

    Directory of Open Access Journals (Sweden)

    S Borna

    2008-06-01

    Full Text Available Background: Preterm labor is a major contributor to neonatal morbidity and mortality and results in increased obstetric and pediatric care costs. The purpose of this study was to assess the effects of vaginal progesterone for maintenance therapy following treatment of threatened preterm labor for preventing preterm birth.Methods: The study included 70 singleton pregnant women with preterm labor with intact membranes. Patients were randomized to receive either maintenance vaginal progesterone therapy (n=37 administered (400 mg daily or no treatment (controls, n=33 after discontinuation of acute intravenous tocolysis.Results: The two groups were similar with at respect to maternal age, race, parity, gestational age at admission, bishop score, and preterm delivery risk factors .Compared to the control group, the mean ±SD time gained from initiation of maintenance therapy to delivery (36/1117/9 versus 24/5227/2 (meanSD days, p=0.037 and the gestational age at delivery (36.071.56 vs. 34.51.3 weeks, p=0.041 were higher in the vaginal progesterone maintenance therapy group. No significant differences were found with recurrent preterm labor 13 (35.1% versus 19 (57.6%, p=0.092. Respiratory distress syndrome 4 (10.8% versus 12 (36.4% p=0.021, Low birth weight10 (27% versus, 17 (51.5% p=0.04, birth weight (3101.54±587.9gr versus r 2609.39±662.9gr, p=0.002 were significantly different between the two groups.Conclusion: The gestational age and time gained from initiation of maintenance therapy to delivery were longer in women receiving vaginal maintenance tocolysis with progesterone and improve perinatal outcomes. However, maintenance therapy did not decrease the recurrence of preterm labor episodes.

  6. Progesterone

    Science.gov (United States)

    ... hormone replacement therapy in women who have passed menopause (the change of life) and have not had a hysterectomy (surgery to remove the uterus). Hormone replacement therapy usually includes estrogen, which is used to treat symptoms of menopause and reduce the risk of developing certain diseases. ...

  7. Leucine-based receptor sorting motifs are dependent on the spacing relative to the plasma membrane

    DEFF Research Database (Denmark)

    Geisler, C; Dietrich, J; Nielsen, B L

    1998-01-01

    Many integral membrane proteins contain leucine-based motifs within their cytoplasmic domains that mediate internalization and intracellular sorting. Two types of leucine-based motifs have been identified. One type is dependent on phosphorylation, whereas the other type, which includes an acidic...... amino acid, is constitutively active. In this study, we have investigated how the spacing relative to the plasma membrane affects the function of both types of leucine-based motifs. For phosphorylation-dependent leucine-based motifs, a minimal spacing of 7 residues between the plasma membrane...... and the phospho-acceptor was required for phosphorylation and thereby activation of the motifs. For constitutively active leucine-based motifs, a minimal spacing of 6 residues between the plasma membrane and the acidic residue was required for optimal activity of the motifs. In addition, we found that the acidic...

  8. Kinetic analysis of antagonist-occupied adenosine-A3 receptors within membrane microdomains of individual cells provides evidence of receptor dimerization and allosterism.

    Science.gov (United States)

    Corriden, Ross; Kilpatrick, Laura E; Kellam, Barrie; Briddon, Stephen J; Hill, Stephen J

    2014-10-01

    In our previous work, using a fluorescent adenosine-A3 receptor (A3AR) agonist and fluorescence correlation spectroscopy (FCS), we demonstrated high-affinity labeling of the active receptor (R*) conformation. In the current study, we used a fluorescent A3AR antagonist (CA200645) to study the binding characteristics of antagonist-occupied inactive receptor (R) conformations in membrane microdomains of individual cells. FCS analysis of CA200645-occupied A3ARs revealed 2 species, τD2 and τD3, that diffused at 2.29 ± 0.35 and 0.09 ± 0.03 μm(2)/s, respectively. FCS analysis of a green fluorescent protein (GFP)-tagged A3AR exhibited a single diffusing species (0.105 μm(2)/s). The binding of CA200645 to τD3 was antagonized by nanomolar concentrations of the A3 antagonist MRS 1220, but not by the agonist NECA (up to 300 nM), consistent with labeling of R. CA200645 normally dissociated slowly from the A3AR, but inclusion of xanthine amine congener (XAC) or VUF 5455 during washout markedly accelerated the reduction in the number of particles exhibiting τD3 characteristics. It is notable that this effect was accompanied by a significant increase in the number of particles with τD2 diffusion. These data show that FCS analysis of ligand-occupied receptors provides a unique means of monitoring ligand A3AR residence times that are significantly reduced as a consequence of allosteric interaction across the dimer interface © FASEB.

  9. Activity ranking of synthetic analogs targeting vascular endothelial growth factor receptor 2 by an integrated cell membrane chromatography system.

    Science.gov (United States)

    Wang, Dongyao; Lv, Diya; Chen, Xiaofei; Liu, Yue; Ding, Xuan; Jia, Dan; Chen, Langdong; Zhu, Zhenyu; Cao, Yan; Chai, Yifeng

    2015-12-01

    Evaluating the biological activities of small molecules represents an important part of the drug discovery process. Cell membrane chromatography (CMC) is a well-developed biological chromatographic technique. In this study, we have developed combined SMMC-7721/CMC and HepG2/CMC with high-performance liquid chromatography and time-of-flight mass spectrometry to establish an integrated screening platform. These systems was subsequently validated and used for evaluating the activity of quinazoline compounds, which were designed and synthesized to target vascular endothelial growth factor receptor 2. The inhibitory activities of these compounds towards this receptor were also tested using a classical caliper mobility shift assay. The results revealed a significant correlation between these two methods (R(2) = 0.9565 or 0.9420) for evaluating the activities of these compounds. Compared with traditional methods of evaluating the activities analogous compounds, this integrated cell membrane chromatography screening system took less time and was more cost effective, indicating that it could be used as a practical method in drug discovery. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Identification of receptors responsible for binding of the mannose specific lectin to the gut epithelial membrane of the target insects.

    Science.gov (United States)

    Majumder, Pralay; Banerjee, Santanu; Das, Sampa

    2004-01-01

    The sap-sucking homopteran insects, commonly known as aphids and leafhoppers are responsible for a huge amount of lost productivity of mustard, chickpea, cabbage, rice and many other important crops. Due to their unique feeding habits and ability to build up a huge population in a very short time, they are very difficult to control. The objective of the ongoing program is to develop insect-resistant crop species through genetic engineering techniques to combat the yield losses, which necessitates the identification of appropriate control elements. In this direction, mannose-binding 25 kDa lectins have been purified from leaves of garlic, Diffenbachia sequina and tubers of Colocasia esculanta. The purified lectins have been analyzed in SDS-PAGE. The effectiveness of these lectins against chickpea aphids, mustard aphids and green leaf hoppers of rice have been tested. The LC(50) value of each lectin against different insects had been monitored [1,2]. Through immunolocalization analysis, the binding of the lectin had been demonstrated at the epithelial membrane of the midgut of the lectin-treated insects [1]. Receptor proteins of brush border membrane vesicle (BBMV) of the target insects, responsible for binding of the lectin to the midgut of the epithelial layer have been purified and analyzed through ligand assay. Biochemical studies have been undertaken to investigate the lectin-receptor interaction at molecular level.

  11. Observation of Network Dynamics of Ryanodine Receptors on Skeletal Muscle Sarcoplasmic Reticulum Membranes

    Directory of Open Access Journals (Sweden)

    Hongli Hu

    2016-06-01

    Full Text Available Rabbit muscle vesicles derived from sarcoplasmic reticulum were used as a material in studying networks of ryanodine receptors by cryo electron tomography. Three-dimensional analysis reveals the dynamical features of these networks. It was found that the connection angles were rotated along the transmembrane axis of ryanodine receptors. Majority of the connections was observed at domains 6/6 of ryanodine receptors while a small group of connections were showed at domains 9/10. The flexible rotation and connection shift seem to facilitate the extension of an annular network on the wall of the sarcoplasmic reticulum in a triad.

  12. TRH receptor mobility in the plasma membrane is strongly affected by agonist binding and by interaction with some cognate signaling proteins.

    Science.gov (United States)

    Moravcova, Radka; Melkes, Barbora; Novotny, Jiri

    2018-02-01

    Extensive research has been dedicated to elucidating the mechanisms of signal transduction through different G protein-coupled receptors (GPCRs). However, relatively little is known about the regulation of receptor movement within the cell membrane upon ligand binding. In this study we focused our attention on the thyrotropin-releasing hormone (TRH) receptor that typically couples to G q/11 proteins. We monitored receptor diffusion in the plasma membrane of HEK293 cells stably expressing yellow fluorescent protein (YFP)-tagged TRH receptor (TRHR-YFP) by fluorescence recovery after photobleaching (FRAP). FRAP analysis indicated that the lateral movement of the TRH receptor was markedly reduced upon TRH binding as the value of its diffusion coefficient fell down by 55%. This effect was prevented by the addition of the TRH receptor antagonist midazolam. We also found that siRNA-mediated knockdown of G q/11 α, Gβ, β-arrestin2 and phospholipase Cβ1, but not of G i α1, β-arrestin1 or G protein-coupled receptor kinase 2, resulted in a significant decrease in the rate of TRHR-YFP diffusion, indicating the involvement of the former proteins in the regulation of TRH receptor behavior. The observed partial reduction of the TRHR-YFP mobile fraction caused by down-regulation of G i α1 and β-arrestin1 suggests that these proteins may also play distinct roles in THR receptor-mediated signaling. These results demonstrate for the first time that not only agonist binding but also abundance of some signaling proteins may strongly affect TRH receptor dynamics in the plasma membrane.

  13. 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.

  14. Receptor-Targeted Nipah Virus Glycoproteins Improve Cell-Type Selective Gene Delivery and Reveal a Preference for Membrane-Proximal Cell Attachment.

    Directory of Open Access Journals (Sweden)

    Ruben R Bender

    2016-06-01

    Full Text Available Receptor-targeted lentiviral vectors (LVs can be an effective tool for selective transfer of genes into distinct cell types of choice. Moreover, they can be used to determine the molecular properties that cell surface proteins must fulfill to act as receptors for viral glycoproteins. Here we show that LVs pseudotyped with receptor-targeted Nipah virus (NiV glycoproteins effectively enter into cells when they use cell surface proteins as receptors that bring them closely enough to the cell membrane (less than 100 Å distance. Then, they were flexible in receptor usage as demonstrated by successful targeting of EpCAM, CD20, and CD8, and as selective as LVs pseudotyped with receptor-targeted measles virus (MV glycoproteins, the current standard for cell-type specific gene delivery. Remarkably, NiV-LVs could be produced at up to two orders of magnitude higher titers compared to their MV-based counterparts and were at least 10,000-fold less effectively neutralized than MV glycoprotein pseudotyped LVs by pooled human intravenous immunoglobulin. An important finding for NiV-LVs targeted to Her2/neu was an about 100-fold higher gene transfer activity when particles were targeted to membrane-proximal regions as compared to particles binding to a more membrane-distal epitope. Likewise, the low gene transfer activity mediated by NiV-LV particles bound to the membrane distal domains of CD117 or the glutamate receptor subunit 4 (GluA4 was substantially enhanced by reducing receptor size to below 100 Å. Overall, the data suggest that the NiV glycoproteins are optimally suited for cell-type specific gene delivery with LVs and, in addition, for the first time define which parts of a cell surface protein should be targeted to achieve optimal gene transfer rates with receptor-targeted LVs.

  15. Inhibiting PTEN protects hippocampal neurons against stretch injury by decreasing membrane translocation of AMPA receptor GluR2 subunit.

    Directory of Open Access Journals (Sweden)

    Yuan Liu

    Full Text Available The AMPA type of glutamate receptors (AMPARs-mediated excitotoxicity is involved in the secondary neuronal death following traumatic brain injury (TBI. But the underlying cellular and molecular mechanisms remain unclear. In this study, the role of phosphatase and tensin homolog deleted on chromosome 10 (PTEN in GluR2-lacking AMPARs mediated neuronal death was investigated through an in vitro stretch injury model of neurons. It was indicated that both the mRNA and protein levels of PTEN were increased in cultured hippocampal neurons after stretch injury, which was associated with the decreasing expression of GluR2 subunits on the surface of neuronal membrane. Inhibition of PTEN activity by its inhibitor can promote the survival of neurons through preventing reduction of GluR2 on membrane. Moreover, the effect of inhibiting GluR2-lacking AMPARs was similar to PTEN suppression-mediated neuroprotective effect in stretch injury-induced neuronal death. Further evidence identified that the total GluR2 protein of neurons was not changed in all groups. So inhibition of PTEN or blockage of GluR2-lacking AMPARs may attenuate the death of hippocampal neurons post injury through decreasing the translocation of GluR2 subunit on the membrane effectively.

  16. Membrane signalling complexes: implications for development of functionally selective ligands modulating heptahelical receptor signalling.

    Science.gov (United States)

    Piñeyro, Graciela

    2009-02-01

    Technological development has considerably changed the way in which we evaluate drug efficacy and has led to a conceptual revolution in pharmacological theory. In particular, molecular resolution assays have revealed that heptahelical receptors may adopt multiple active conformations with unique signalling properties. It is therefore becoming widely accepted that ligand ability to stabilize receptor conformations with distinct signalling profiles may allow to direct the stimulus generated by an activated receptor towards a specific signalling pathway. This capacity to induce only a subset of the ensemble of responses regulated by a given receptor has been termed "functional selectivity" (or "stimulus trafficking"), and provides the bases for a highly specific regulation of receptor signalling. Concomitant with these observations, heptahelical receptors have been shown to associate with G proteins and effectors to form multimeric arrays. These complexes are constitutively formed during protein synthesis and are targeted to the cell surface as integral signalling units. Herein we summarize evidence supporting the existence of such constitutive signalling arrays and analyze the possibility that they may constitute viable targets for developing ligands with "functional selectivity".

  17. A new liver function test using the asialoglycoprotein-receptor system on the liver cell membrane, 2

    International Nuclear Information System (INIS)

    Kawa, Soukichi; Hazama, Hiroshi; Kojima, Michimasa

    1986-01-01

    We produced labeled neoglycoprotein (GHSA) that is physiologically equivalent to ASGP, and quantitatively examined whether its uptake by the liver is dose-related using the following methods: 1) binding assay between GHSA and ASGP receptors, 2) measurement of the liver extraction ratio in the initial circulation following administration into the portal vein, and 3) measurement of clearance in normal rats and rats with galacosamine-induced acute liver disorder. The binding assay showed a linear relationship between the concentration of 125 I-GHSA and the amount of ASGP receptors obtained from the rat liver. A membrane assay using 125 I-GHSA and the liver cell membrane revealed similar results. The liver extraction ratio in the initial circulation following the administration into the portal vein of normal rabbits was highly dose-dependent (r = -0.95 in the range of 5 - 100 μg GHSA). Serial imaging of 99m Tc-GHSA during two-hour period after administration into the peripheral blood showed specific accumulation in the liver beginning immediately after the intravenous injection and subsequent transport mainly via the biliary system into the small intestine in the normal rat and mainly into the urine in the bile duct ligated rat. As a dynamic model of 99m Tc-GHSA, its circulation through the heart and liver and inactivated release from the liver was used, and two-compartment analysis was made on measurement curves in the heart and liver to obtain clearance parameters. The concentration of administered 99m Tc-GHSA (50 - 100 μg/100 g body weight) showed a positive linear relationship with clearance. Administration of 50 μg/100 g body weight of 99m Tc-GHSA revealed a significant correlation (p < 0.001) between clearance and ASGP receptor activity in normal rats and rats with galactosamine-induced acute liver disorder. (J.P.N.)

  18. Premature progesterone rise in ART-cycles.

    Science.gov (United States)

    Lawrenz, B; Melado, L; Fatemi, H M

    2018-01-06

    Premature rise of progesterone during the late follicular phase in stimulated IVF cycles is a frequent event and its effect on the endometrial receptivity and on the ART (Assisted Reproductive Technique) - outcome has become a matter of intense debate and research. An emerging body of evidence demonstrates that premature progesterone rise does have a negative impact on the outcome of the ART-success. Until now, the exact cause of progesterone elevation is not fully clear, however lately published studies points to the fact, that premature progesterone elevation might be caused by enhanced FSH stimulation. The impact of elevated peripheral progesterone levels seems to be mainly on the endometrium and the window of implantation, leading to an asynchrony between the endometrium and the developing embryo. Hence, new data show additional an influence on the embryo quality. This review aims to summarize the up-to-date knowledge on the causes of premature progesterone rise during hormonal stimulation, on its influence on endometrial receptivity and embryo quality, on the impact on pregnancy and live birth rates as well as on the possible strategies to prevent this event or to deal with premature progesterone elevation in case it could not be avoided. Copyright © 2018 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  19. Maintenance of membrane organization in the aging mouse brain as the determining factor for preventing receptor dysfunction and for improving response to anti-Alzheimer treatments.

    Science.gov (United States)

    Colin, Julie; Thomas, Mélanie H; Gregory-Pauron, Lynn; Pinçon, Anthony; Lanhers, Marie-Claire; Corbier, Catherine; Claudepierre, Thomas; Yen, Frances T; Oster, Thierry; Malaplate-Armand, Catherine

    2017-06-01

    Although a major risk factor for Alzheimer's disease (AD), the "aging" parameter is not systematically considered in preclinical validation of anti-AD drugs. To explore how aging affects neuronal reactivity to anti-AD agents, the ciliary neurotrophic factor (CNTF)-associated pathway was chosen as a model. Comparison of the neuroprotective properties of CNTF in 6- and 18-month old mice revealed that CNTF resistance in the older animals is associated with the exclusion of the CNTF-receptor subunits from rafts and their subsequent dispersion to non-raft cortical membrane domains. This age-dependent membrane remodeling prevented both the formation of active CNTF-receptor complexes and the activation of prosurvival STAT3 and ERK1/2 pathways, demonstrating that age-altered membranes impaired the reactivity of potential therapeutic targets. CNTF-receptor distribution and CNTF signaling responses were improved in older mice receiving dietary docosahexaenoic acid, with CNTF-receptor functionality being similar to those of younger mice, pointing toward dietary intervention as a promising adjuvant strategy to maintain functional neuronal membranes, thus allowing the associated receptors to respond appropriately to anti-AD agents. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Membrane receptors for very low density lipoprotein (VLDL) inhibitor of lymphocyte proliferation

    International Nuclear Information System (INIS)

    Yi, P.I.; Beck, G.; Zucker, S.

    1981-01-01

    Physiologic concentrations of human plasma very low density lipoproteins inhibit the DNA synthesis of lymphocytes stimulated by allogeneic cells or lectins. In this report reachers have compared the effects of isolated lipoproteins [very low density lipoproteins (VLDL), low density lipoproteins (LDL), and high density lipoproteins (HDL)] and lipoprotein-depleted plasma (LDP) on DNA synthesis by phytohemagglutinin-stimulated human lymphocytes. The relative potency for the inhibition of lymphocyte proliferation was VLDL greater than LDL greater than HDL greater than LDP. Fifty percent inhibition of DNA synthesis was observed at a VLDL protein concentration of 1.5--2.0 microgram/ml. Researchers have further demonstrated the presence of specific receptors for VLDL on human lymphocytes. Native VLDL was more effective than LDL in competing for 125I-VLDL binding sites. Subsequent to binding to lymphocytes, 125I-VLDL was internalized and degraded to acid-soluble products. Based on a Scatchard analysis of VLDL binding at 4 degrees C, the number of VLDL receptors per lymphocyte was estimated at 28,000 +/- 1300. Based on an estimated mean binding affinity for the VLDL receptor complex at half saturation of approximately 8.8 X 10(7) liter/mole, it is estimated that 91% of lymphocyte VLDL receptors are occupied at physiologic VLDL concentrations in blood. Although the immune regulatory role of plasma lipoproteins is uncertain, researchers suggest tha VLDL and LDL-In may maintain circulating blood lymphocytes in a nonproliferative state via their respective cell receptor mechanisms

  1. G Protein-Coupled Receptors: Extranuclear Mediators for the Non-Genomic Actions of Steroids

    Directory of Open Access Journals (Sweden)

    Chen Wang

    2014-09-01

    Full Text Available Steroids hormones possess two distinct actions, a delayed genomic effect and a rapid non-genomic effect. Rapid steroid-triggered signaling is mediated by specific receptors localized most often to the plasma membrane. The nature of these receptors is of great interest and accumulated data suggest that G protein-coupled receptors (GPCRs are appealing candidates. Increasing evidence regarding the interaction between steroids and specific membrane proteins, as well as the involvement of G protein and corresponding downstream signaling, have led to identification of physiologically relevant GPCRs as steroid extranuclear receptors. Examples include G protein-coupled receptor 30 (GPR30 for estrogen, membrane progestin receptor for progesterone, G protein-coupled receptor family C group 6 member A (GPRC6A and zinc transporter member 9 (ZIP9 for androgen, and trace amine associated receptor 1 (TAAR1 for thyroid hormone. These receptor-mediated biological effects have been extended to reproductive development, cardiovascular function, neuroendocrinology and cancer pathophysiology. However, although great progress have been achieved, there are still important questions that need to be answered, including the identities of GPCRs responsible for the remaining steroids (e.g., glucocorticoid, the structural basis of steroids and GPCRs’ interaction and the integration of extranuclear and nuclear signaling to the final physiological function. Here, we reviewed the several significant developments in this field and highlighted a hypothesis that attempts to explain the general interaction between steroids and GPCRs.

  2. Simvastatin treatment reduces the cholesterol content of membrane/lipid rafts, implicating the N -methyl-D-aspartate receptor in anxiety: a literature review

    Directory of Open Access Journals (Sweden)

    Júlia Niehues da Cruz

    2017-04-01

    Full Text Available ABSTRACT Membrane/lipid rafts (MLRs are plasmalemmal microdomains that are essential for neuronal signaling and synaptic development/stabilization. Inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme-A reductase (statins can disable the N-methyl-D-aspartate (NMDA receptor through disruption of MLRs and, in turn, decrease NMDA-mediated anxiety. This hypothesis will contribute to understanding the critical roles of simvastatin in treating anxiety via the NMDA receptor.

  3. Lectin receptor kinase LecRK-b2 localizes to plasma membrane and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-20

    -b2, has been characterized. Confocal microscopy images showed that the LecRK-b2-GFP fusion protein is localized to plasma membrane. The results of yeast 2 hybrid showed that lectin domain of LecRK-b2 had self-.

  4. Lectin receptor kinase LecRK-b2 localizes to plasma membrane and ...

    African Journals Online (AJOL)

    -b2, has been characterized. Confocal microscopy images showed that the LecRK-b2-GFP fusion protein is localized to plasma membrane. The results of yeast 2 hybrid showed that lectin domain of LecRK-b2 had selfinteraction, while the ...

  5. Continuous versus cyclic progesterone exposure differentially regulates hippocampal gene expression and functional profiles.

    Directory of Open Access Journals (Sweden)

    Liqin Zhao

    Full Text Available This study investigated the impact of chronic exposure to continuous (CoP4 versus cyclic progesterone (CyP4 alone or in combination with 17β-estradiol (E2 on gene expression profiles targeting bioenergetics, metabolism and inflammation in the adult female rat hippocampus. High-throughput qRT-PCR analyses revealed that ovarian hormonal depletion induced by ovariectomy (OVX led to multiple significant gene expression alterations, which were to a great extent reversed by co-administration of E2 and CyP4. In contrast, co-administration of E2 and CoP4 induced a pattern highly resembling OVX. Bioinformatics analyses further revealed clear disparities in functional profiles associated with E2+CoP4 and E2+CyP4. Genes involved in mitochondrial energy (ATP synthase α subunit; Atp5a1, redox homeostasis (peroxiredoxin 5; Prdx5, insulin signaling (insulin-like growth factor I; Igf1, and cholesterol trafficking (liver X receptor α subtype; Nr1h3, differed in direction of regulation by E2+CoP4 (down-regulation relative to OVX and E2+CyP4 (up-regulation relative to OVX. In contrast, genes involved in amyloid metabolism (β-secretase; Bace1 differed only in degree of regulation, as both E2+CoP4 and E2+CyP4 induced down-regulation at different efficacy. E2+CyP4-induced changes could be associated with regulation of progesterone receptor membrane component 1(Pgrmc1. In summary, results from this study provide evidence at the molecular level that differing regimens of hormone therapy (HT can induce disparate gene expression profiles in brain. From a translational perspective, confirmation of these results in a model of natural menopause, would imply that the common regimen of continuous combined HT may have adverse consequences whereas a cyclic combined regimen, which is more physiological, could be an effective strategy to maintain neurological health and function throughout menopausal aging.

  6. Inhibition of Progesterone Metabolism Mimics the Effect of Progesterone Withdrawal on Forced Swim Test Immobility

    OpenAIRE

    Beckley, Ethan H.; Finn, Deborah A.

    2007-01-01

    Withdrawal from high levels of progesterone in rodents has been proposed as a model for premenstrual syndrome or postpartum depression. Forced swim test (FST) immobility, used to model depression, was assessed in intact female DBA/2J mice following progesterone withdrawal (PWD) or treatment with the 5α-reductase inhibitor finasteride. Following 5 daily progesterone injections (5 mg/kg IP) FST immobility increased only in mice withdrawn for 3 days (p < .05). In another experiment, 3 days of PW...

  7. Endocannabinoid 1 and 2 (CB(1); CB(2)) receptor agonists affect negatively cow luteal function in vitro.

    Science.gov (United States)

    Weems, Y S; Lewis, A W; Neuendorff, D A; Randel, R D; Weems, C W

    2009-12-01

    Thirty to 40% of pregnancies are lost during the first third of pregnancy, which has been hypothesized to be due to inadequate progesterone secretion by the corpus luteum. Loss of luteal progesterone secretion during the estrous cycle is via uterine secretion of prostaglandin F(2)alpha (PGF(2)alpha). Cow luteal tissue secretion of prostaglandins (PG) E (PGE(1)+PGE(2)) and PGF(2)alpha are derived from precursors in membrane phospholipids. Cow luteal tissue secretion of PGE and PGF(2)alpha increased linearly with time in culture with the PGE: ratio being 1:1. PGE(1) or PGE(2) are luteotropic in cows and ewes and antiluteolytic in vitro and in vivo in ewes. Endocannabinoids are also derived from phospholipids and are associated with infertility, presumably by reducing implantation; however, effects of endocannabinoids on luteal function have not been addressed. The objective of this experiment was to determine the effects of endocannabinoid type 1 and 2 receptor agonists and receptor antagonists or a fatty acid amide hydrolase (FAAH; catabolizes endocannabinoids) inhibitor, PGE(1), or PGF(2)alpha on bovine luteal secretion of progesterone, PGE, and PGF(2)alphain vitro. PGE and PGF(2)alpha was increased (P or =0.05) with time in vehicle-treated luteal slices in vitro. Progesterone was increased (Pcow luteal function in vitro and that the corpus luteum may also be a site for endocannabinoid decreased fertility as well as a reduction in implantation.

  8. Muscarinic receptor control of pyramidal neuron membrane potential in the medial prefrontal cortex (mPFC) in rats.

    Science.gov (United States)

    Kurowski, P; Gawlak, M; Szulczyk, P

    2015-09-10

    Damage to the cholinergic input to the prefrontal cortex has been implicated in neuropsychiatric disorders. Cholinergic endings release acetylcholine, which activates nicotinic and/or G-protein-coupled muscarinic receptors. Muscarinic receptors activate transduction systems, which control cellular effectors that regulate the membrane potential in medial prefrontal cortex (mPFC) neurons. The mechanisms responsible for the cholinergic-dependent depolarization of mPFC layer V pyramidal neurons in slices obtained from young rats were elucidated in this study. Glutamatergic and GABAergic transmission as well as tetrodotoxin (TTX)-sensitive Na(+) and voltage-dependent Ca(++) currents were eliminated. Cholinergic receptor stimulation by carbamoylcholine chloride (CCh; 100 μM) evoked depolarization (10.0 ± 1.3 mV), which was blocked by M1/M4 (pirenzepine dihydrochloride, 2 μM) and M1 (VU 0255035, 5 μM) muscarinic receptor antagonists and was not affected by a nicotinic receptor antagonist (mecamylamine hydrochloride, 10 μM). CCh-dependent depolarization was attenuated by extra- (20 μM) or intracellular (50 μM) application of an inhibitor of the βγ-subunit-dependent transduction system (gallein). It was also inhibited by intracellular application of a βγ-subunit-binding peptide (GRK2i, 10μM). mPFC pyramidal neurons express Nav1.9 channels. CCh-dependent depolarization was abolished in the presence of antibodies against Nav1.9 channels in the intracellular solution and augmented by the presence of ProTx-I toxin (100 nM) in the extracellular solution. CCh-induced depolarization was not affected by the following reagents: intracellular transduction system blockers, including U-73122 (10 μM), chelerythrine chloride (5 μM), SQ 22536 (100 μM) and H-89 (2 μM); channel blockers, including Ba(++) ions (200 μM), apamin (100 nM), flufenamic acid (200 μM), 2-APB (200 μM), SKF 96365 (50 μM), and ZD 7288 (50 μM); and a Na(+)/Ca(++) exchanger blocker, benzamil (20

  9. Progesterone inhibits epithelial-to-mesenchymal transition in endometrial cancer.

    Directory of Open Access Journals (Sweden)

    Paul H van der Horst

    Full Text Available BACKGROUND: Every year approximately 74,000 women die of endometrial cancer, mainly due to recurrent or metastatic disease. The presence of tumor infiltrating lymphocytes (TILs as well as progesterone receptor (PR positivity has been correlated with improved prognosis. This study describes two mechanisms by which progesterone inhibits metastatic spread of endometrial cancer: by stimulating T-cell infiltration and by inhibiting epithelial-to-mesenchymal cell transition (EMT. METHODOLOGY AND PRINCIPAL FINDINGS: Paraffin sections from patients with (n = 9 or without (n = 9 progressive endometrial cancer (recurrent or metastatic disease were assessed for the presence of CD4+ (helper, CD8+ (cytotoxic and Foxp3+ (regulatory T-lymphocytes and PR expression. Progressive disease was observed to be associated with significant loss of TILs and loss of PR expression. Frozen tumor samples, used for genome-wide expression analysis, showed significant regulation of pathways involved in immunesurveillance, EMT and metastasis. For a number of genes, such as CXCL14, DKK1, DKK4, PEG10 and WIF1, quantitive RT-PCR was performed to verify up- or downregulation in progressive disease. To corroborate the role of progesterone in regulating invasion, Ishikawa (IK endometrial cancer cell lines stably transfected with PRA (IKPRA, PRB (IKPRB and PRA+PRB (IKPRAB were cultured in presence/absence of progesterone (MPA and used for genome-wide expression analysis, Boyden- and wound healing migration assays, and IHC for known EMT markers. IKPRB and IKPRAB cell lines showed MPA induced inhibition of migration and loss of the mesenchymal marker vimentin at the invasive front of the wound healing assay. Furthermore, pathway analysis of significantly MPA regulated genes showed significant down regulation of important pathways involved in EMT, immunesuppression and metastasis: such as IL6-, TGF-β and Wnt/β-catenin signaling. CONCLUSION: Intact progesterone signaling in non

  10. Ligand binding to G protein-coupled receptors in tethered cell membranes

    DEFF Research Database (Denmark)

    Martinez, Karen L.; Meyer, Bruno H.; Hovius, Ruud

    2003-01-01

    G protein-coupled receptors (GPCRs) constitute a large class of seven transmembrane proteins, which bind selectively agonists or antagonists with important consequences for cellular signaling and function. Comprehension of the molecular details of ligand binding is important for the understanding...

  11. Cell type specificity of signaling: view from membrane receptors distribution and their downstream transduction networks.

    Science.gov (United States)

    He, Ying; Yu, Zhonghao; Ge, Dongya; Wang-Sattler, Rui; Thiesen, Hans-Jürgen; Xie, Lu; Li, Yixue

    2012-09-01

    Studies on cell signaling pay more attention to spatial dynamics and how such diverse organization can relate to high order of cellular capabilities. To overview the specificity of cell signaling, we integrated human receptome data with proteome spatial expression profiles to systematically investigate the specificity of receptors and receptor-triggered transduction networks across 62 normal cell types and 14 cancer types. Six percent receptors showed cell-type-specific expression, and 4% signaling networks presented enriched cell-specific proteins induced by the receptors. We introduced a concept of "response context" to annotate the cell-type dependent signaling networks. We found that most cells respond similarly to the same stimulus, as the "response contexts" presented high functional similarity. Despite this, the subtle spatial diversity can be observed from the difference in network architectures. The architecture of the signaling networks in nerve cells displayed less completeness than that in glandular cells, which indicated cellular-context dependent signaling patterns are elaborately spatially organized. Likewise, in cancer cells most signaling networks were generally dysfunctional and less complete than that in normal cells. However, glioma emerged hyper-activated transduction mechanism in malignant state. Receptor ATP6AP2 and TNFRSF21 induced rennin-angiotensin and apoptosis signaling were found likely to explain the glioma-specific mechanism. This work represents an effort to decipher context-specific signaling network from spatial dimension. Our results indicated that although a majority of cells engage general signaling response with subtle differences, the spatial dynamics of cell signaling can not only deepen our insights into different signaling mechanisms, but also help understand cell signaling in disease.

  12. Radioimmunoassay for progesterone in bovine milk

    International Nuclear Information System (INIS)

    Ruiz, Miriam; Figueredo, Nancy; Castillo, Sonia; Pizarro

    2002-01-01

    A system for the measurement of progesterone in bovine milk by radioimmunoassay has been developed and validated. This assay includes an iodine tracer purified by HPLC, the standard prepared in fat-free milk and an antibody anti-progesterone combined with second antibody. The detection limit of the assay is at 0.2 nmol/L calculated from the maximum binding menus two standard deviations and the precision is satisfactory. In the recovery assay was used 4 milk different samples and the result was 98% of recuperation. The progesterone was determinate in milk samples from post-partum animals taking samples three times per week for 40 days. The assay is simple, rapid and possibility the progesterone measurement without sample dilution, distinguish the cyclic changes of this hormone that reflect the ovarian activity in the animals. (author)

  13. Sensor and instrumentation for progesterone detection

    KAUST Repository

    Zia, Asif I.

    2012-05-01

    The reported research work uses a real time and noninvasive method to detect progesterone hormone concentration in purified water using Electrochemical Impedance Spectroscopy (E.I.S.) technique. Planar capacitive sensor, consisting of inter-digitated microelectrodes, is designed and fabricated on silicon substrate using thin-film Microelectromechanical system (MEMS) based semiconductor device fabrication technology. The sensor in conjunction with EIS is used to evaluate conductivity, permeability and dielectric properties of reproductive hormone progesterone and its concentration quantification in purified water. Impedance spectrums are obtained with various concentrations of the hormone in purified water by using an electric circuit in order to extract sample conductance. Relationship of sample conductance with progesterone concentration level is studied in this research work. The ability of E.I.S. to detect progesterone concentration is aimed to be used in dairy farming industry in order to obtain better reproductive performance of the dairy cattle. © 2012 IEEE.

  14. Polymer-immobilized liquid membrane transport of palladium (II) from nitric acid media using some thia extractants as novel receptors

    International Nuclear Information System (INIS)

    Shukla, J.P.

    1996-01-01

    Carrier-facilitated co-transport of Pd (II) from dilute acidic nitrate solutions was examined across a polymer-immobilized liquid membrane (PILM) deploying S 6 -pentano-36 (S 6 -P-36), bis-(2-ethylhexyl) sulfoxide (BESO) and bis (2, 4, 4 trimethyl pentyl) monothio phosphinic acid (Cyanex 302) as the novel receptors. The study carried out to distinguish the driving force between H + and NO 3 - ion for the cation transport across PILM, indicated that NO 3 - ion not the H + ion seems to be the driving force for Pd (II) transport under the present conditions for both BESO-PILM and S 6 -P-36-PILM systems. Recovery of palladium from acidic process effluents generated in Purex reprocessing of spent fuels was successfully achieved. 39 refs., 8 figs., 7 tabs

  15. Influence of monoolein on progesterone transdermal delivery

    Directory of Open Access Journals (Sweden)

    Wanessa de Souza Cardoso Quintão

    2015-12-01

    Full Text Available abstract This work aimed to investigate in vitro the influence of monoolein (MO on progesterone (PG transdermal delivery and skin retention. Information about the role of MO as an absorption enhancer for lipophilic molecules can help on innovative product development capable of delivering the hormone through the skin in a consistent manner, improving transdermal therapy of hormonal replacement. MO was dispersed in propylene glycol under heat at concentrations of 0% (control, 5% w/w, 10% w/w and 20% w/w. Then, 0.6% of PG (w/w was added to each formulation. Permeation profile of the hormone was determined in vitro for 48 h using porcine skin in Franz diffusion cells. PG permeation doubled when 5% (w/w of MO was present in formulation in comparison to both the control and higher MO concentrations (10% and 20% w/w. An equal trend was observed for PG retention in stratum corneum (SC and reminiscent skin (E+D. PG release rates from the MO formulations, investigated using cellulose membranes, revealed that concentrations of MO higher than 5% (w/w hindered PG release, which indeed negatively reflected on the hormone permeation through the skin. In conclusion, this work demonstrated the feasibility of MO addition (at 5% w/w in formulations as a simple method to increase transdermal PG delivery for therapies of hormonal replacement. In contrast, higher MO concentrations (from 10% to 20% w/w can control active release, and this approach could be extrapolated to other lipophilic, low-molecular-weight molecules.

  16. Microarray Analysis on Gene Regulation by Estrogen, Progesterone and Tamoxifen in Human Endometrial Stromal Cells

    Science.gov (United States)

    Ren, Chun-E; Zhu, Xueqiong; Li, Jinping; Lyle, Christian; Dowdy, Sean; Podratz, Karl C.; Byck, David; Chen, Hai-Bin; Jiang, Shi-Wen

    2015-01-01

    Epithelial stromal cells represent a major cellular component of human uterine endometrium that is subject to tight hormonal regulation. Through cell-cell contacts and/or paracrine mechanisms, stromal cells play a significant role in the malignant transformation of epithelial cells. We isolated stromal cells from normal human endometrium and investigated the morphological and transcriptional changes induced by estrogen, progesterone and tamoxifen. We demonstrated that stromal cells express appreciable levels of estrogen and progesterone receptors and undergo different morphological changes upon hormonal stimulation. Microarray analysis indicated that both estrogen and progesterone induced dramatic alterations in a variety of genes associated with cell structure, transcription, cell cycle, and signaling. However, divergent patterns of changes, and in some genes opposite effects, were observed for the two hormones. A large number of genes are identified as novel targets for hormonal regulation. These hormone-responsive genes may be involved in normal uterine function and the development of endometrial malignancies. PMID:25782154

  17. Microarray Analysis on Gene Regulation by Estrogen, Progesterone and Tamoxifen in Human Endometrial Stromal Cells

    Directory of Open Access Journals (Sweden)

    Chun-E Ren

    2015-03-01

    Full Text Available Epithelial stromal cells represent a major cellular component of human uterine endometrium that is subject to tight hormonal regulation. Through cell-cell contacts and/or paracrine mechanisms, stromal cells play a significant role in the malignant transformation of epithelial cells. We isolated stromal cells from normal human endometrium and investigated the morphological and transcriptional changes induced by estrogen, progesterone and tamoxifen. We demonstrated that stromal cells express appreciable levels of estrogen and progesterone receptors and undergo different morphological changes upon hormonal stimulation. Microarray analysis indicated that both estrogen and progesterone induced dramatic alterations in a variety of genes associated with cell structure, transcription, cell cycle, and signaling. However, divergent patterns of changes, and in some genes opposite effects, were observed for the two hormones. A large number of genes are identified as novel targets for hormonal regulation. These hormone-responsive genes may be involved in normal uterine function and the development of endometrial malignancies.

  18. Delta-Opioid receptors exhibit high efficiency when activating trimeric G proteins in membrane domains

    Czech Academy of Sciences Publication Activity Database

    Bouřová, Lenka; Koštrnová, Alexandra; Hejnová, Lucie; Moravcová, Zuzana; Moon, H. E.; Novotný, Jiří; Milligan, G.; Svoboda, Petr

    2003-01-01

    Roč. 85, č. 1 (2003), s. 34-49 ISSN 0022-3042 R&D Projects: GA MŠk LN00A026; GA ČR GA309/01/0255 Grant - others:Welcome Trust(GB) xx Institutional research plan: CEZ:AV0Z5011922 Keywords : membrane domains * GTPase activity * G protein coupling Subject RIV: CE - Biochemistry Impact factor: 4.825, year: 2003

  19. Chemical Kinetics of Progesterone Radioimmunoassay System

    International Nuclear Information System (INIS)

    Abdel-Fattah, A.A.; Moustsfs, K.A.; El-Kolally, M.T.

    2004-01-01

    Progesterone is one of the steroids secreted by the corpus Iuteum in females during the menstrual cycle, and in a much higher amount by the placenta during pregnancy. It is also secreted in a minor quantities by the adrenal cortex in both males and females. Measurement of serum progesterone represents one of diagnostic values in menstrual disorders and infertility. The progesterone radioimmunoassay is based on the competition between unlabelled progesterone and a fixed quantity of 125 I-labeled progesterone for a limited number of binding sites on progesterone specific antibody. Allowing for a fixed amount of magnetizable immunosorbent to react, the antigen-antibody complex is bound on solid particles which are then separated by magnetic rack, and the radioactivity of the solid phase was counted using gamma counter. In this work, the chemical kinetics of the assay was followed, where the specific rate constant (K) was calculated at 4 degree and 37 degree and the activation energy (E act ) were calculated and the reaction rate was deduced

  20. Recycling of glucagon receptor to plasma membrane increases in adipocytes of obese rats by soy protein; implications for glucagon resistance.

    Science.gov (United States)

    Velázquez-Villegas, Laura A; Tovar-Palacio, Claudia; Palacios-González, Berenice; Torres, Nimbe; Tovar, Armando R; Díaz-Villaseñor, Andrea

    2017-10-01

    Hyperglucagonemia contributes to hyperglycemia in type 2 diabetes (T2D). Previously, we have found that soy protein normalized fasting hyperglucagonemia in obese Zucker (fa/fa) rats, sensitizing the HSL-lipolytic signaling pathway in white adipose tissue (WAT), however the mechanism remains unknown. Zucker (fa/fa) rats were fed casein or soy protein diet in combination with soybean or coconut oil. Glucagon receptor (GR) was increased at the plasma membrane of adipocytes of rats fed soy protein compared to those fed casein, without changes in total GR abundance. The protein abundance of Rab4, a GTPase involved in GR fast recycling, was dramatically up-regulated in adipocytes of rats fed soy protein. The proportion of GR bound to Rab4 or to RAMP2, involved in promoting GR ligand-binding and G protein selectivity, increased when soy protein was combined with soybean oil as fat source. In rats fed soy protein with coconut oil, Rab11 levels, a protein involved in the slow recycling of GR, was also increased. Soy protein increases GR recycling to the membrane of adipocytes and its ligand-binding and G protein selectivity, suggesting, it could be used in T2D dietary treatment to reestablish glucagon sensitivity in WAT, leading to the regulation of circulating glucagon levels. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Presynaptic membrane receptors in acetylcholine release modulation in the neuromuscular synapse.

    Science.gov (United States)

    Tomàs, Josep; Santafé, Manel M; Garcia, Neus; Lanuza, Maria A; Tomàs, Marta; Besalduch, Núria; Obis, Teresa; Priego, Mercedes; Hurtado, Erica

    2014-05-01

    Over the past few years, we have studied, in the mammalian neuromuscular junction (NMJ), the local involvement in transmitter release of the presynaptic muscarinic ACh autoreceptors (mAChRs), purinergic adenosine autoreceptors (P1Rs), and trophic factor receptors (TFRs; for neurotrophins and trophic cytokines) during development and in the adult. At any given moment, the way in which a synapse works is largely the logical outcome of the confluence of these (and other) metabotropic signalling pathways on intracellular kinases, which phosphorylate protein targets and materialize adaptive changes. We propose an integrated interpretation of the complementary function of these receptors in the adult NMJ. The activity of a given receptor group can modulate a given combination of spontaneous, evoked, and activity-dependent release characteristics. For instance, P1Rs can conserve resources by limiting spontaneous quantal leak of ACh (an A1 R action) and protect synapse function, because stimulation with adenosine reduces the magnitude of depression during repetitive activity. The overall outcome of the mAChRs seems to contribute to upkeep of spontaneous quantal output of ACh, save synapse function by decreasing the extent of evoked release (mainly an M2 action), and reduce depression. We have also identified several links among P1Rs, mAChRs, and TFRs. We found a close dependence between mAChR and some TFRs and observed that the muscarinic group has to operate correctly if the tropomyosin-related kinase B receptor (trkB) is also to operate correctly, and vice versa. Likewise, the functional integrity of mAChRs depends on P1Rs operating normally. Copyright © 2014 Wiley Periodicals, Inc.

  2. Location of the sulphonylurea receptor at the cytoplasmic face of the beta-cell membrane.

    OpenAIRE

    Schwanstecher, M; Schwanstecher, C; Dickel, C; Chudziak, F; Moshiri, A; Panten, U

    1994-01-01

    1. In insulin-secreting cells the location of the sulphonylurea receptor was examined by use of a sulphonylurea derivative representing the glibenclamide molecule devoid of its cyclohexy moiety (compound III) and a benzenesulphonic acid derivative representing the glibenclamide molecule devoid of its cyclohexylurea moiety (compound IV). At pH 7.4 compound IV is only present in charged form. 2. Lipid solubility declined in the order tolbutamide > compound III > compound IV. 3. The dissociation...

  3. Metal Oxide Nanosensors Using Polymeric Membranes, Enzymes and Antibody Receptors as Ion and Molecular Recognition Elements

    Directory of Open Access Journals (Sweden)

    Magnus Willander

    2014-05-01

    Full Text Available The concept of recognition and biofunctionality has attracted increasing interest in the fields of chemistry and material sciences. Advances in the field of nanotechnology for the synthesis of desired metal oxide nanostructures have provided a solid platform for the integration of nanoelectronic devices. These nanoelectronics-based devices have the ability to recognize molecular species of living organisms, and they have created the possibility for advanced chemical sensing functionalities with low limits of detection in the nanomolar range. In this review, various metal oxides, such as ZnO-, CuO-, and NiO-based nanosensors, are described using different methods (receptors of functionalization for molecular and ion recognition. These functionalized metal oxide surfaces with a specific receptor involve either a complex formation between the receptor and the analyte or an electrostatic interaction during the chemical sensing of analytes. Metal oxide nanostructures are considered revolutionary nanomaterials that have a specific surface for the immobilization of biomolecules with much needed orientation, good conformation and enhanced biological activity which further improve the sensing properties of nanosensors. Metal oxide nanostructures are associated with certain unique optical, electrical and molecular characteristics in addition to unique functionalities and surface charge features which shows attractive platforms for interfacing biorecognition elements with effective transducing properties for signal amplification. There is a great opportunity in the near future for metal oxide nanostructure-based miniaturization and the development of engineering sensor devices.

  4. ( sup 3 H)opipramol labels a novel binding site and sigma receptors in rat brain membranes

    Energy Technology Data Exchange (ETDEWEB)

    Ferris, C.D.; Hirsch, D.J.; Brooks, B.P.; Snowman, A.M.; Snyder, S.H. (Johns Hopkins Univ. School of Medicine, Baltimore, MD (USA))

    1991-02-01

    Opipramol (OP), a clinically effective antidepressant with a tricyclic structure, is inactive as an inhibitor of biogenic amine uptake. ({sup 3}H)Opipramol binds saturably to rat brain membranes (apparent KD = 4 nM, Bmax = 3 pmol/mg of protein). ({sup 3}H)Opipramol binding can be differentiated into haloperidol-sensitive and -resistant components, with Ki values for haloperidol of 1 nM (Bmax = 1 pmol/mg of protein) and 350 nM (Bmax = 1.9 pmol/mg of protein), respectively. The drug specificity of the haloperidol-sensitive component is the same as that of sigma receptors labeled with (+)-({sup 3}H)3-(3-hydroxyphenyl)-N-(1-propyl)piperdine. The haloperidol-resistant component does not correspond to any known neurotransmitter receptor or uptake recognition site. It displays high affinity for phenothiazines and related structures such as perphenazine, clopenthixol, and flupenthixol, whose potencies are comparable to that of opipramol. Because certain of these drugs are more potent at the haloperidol-resistant opipramol site than in exerting any other action, it is possible that this opipramol-selective site may mediate their therapeutic effects.

  5. Exploring a model of human chemokine receptor CCR2 in presence of TAK779: A membrane based molecular dynamics study

    Science.gov (United States)

    Balupuri, Anand; Sobhia, M. Elizabeth

    2014-04-01

    Chemokine receptor 2 (CCR2) is a G-protein coupled receptor (GPCR) and a crucial target for various inflammation-driven diseases. In the present study, molecular docking and molecular dynamics simulations were performed on a CCR2 homology model. This work includes the comparative MD simulations of uncomplexed and ‘antagonist-complexed’ CCR2 models. These simulations yield insights into the binding mechanism of antagonist TAK779 and improve the understanding of various structural changes induced by the ligand in the CCR2 protein. Here, one 20 ns MD simulation was carried out on the uncomplexed CCR2 model in lipid bilayer to explore the effects of lipid membrane on the protein. Another 20 ns MD simulation was performed under the similar conditions on the docked CCR2-TAK779 complex. An alteration in the position and orientation of the ligand in binding site was observed after the simulation. Examination of protein-ligand complex suggested that TAK779 produced a greater structural change on the TM-III, TM-IV, TM-V and TM-VI than TM-I, TM-II and TM-VII. Interaction networks involving the conserved residues of uncomplexed and ‘antagonist-complexed’ CCR2 models were also examined. The major difference was observed to be the role of conserved residues of the DRY motif of TM-III and the NPxxY motif of TM-VII of CCR2.

  6. Analytical use of multi-protein Fluorescence Resonance Energy Transfer to demonstrate membrane-facilitated interactions within cytokine receptor complexes.

    Science.gov (United States)

    Krause, Christopher D; Izotova, Lara S; Pestka, Sidney

    2013-10-01

    Experiments measuring Fluorescence Resonance Energy Transfer (FRET) between cytokine receptor chains and their associated proteins led to hypotheses describing their organization in intact cells. These interactions occur within a larger protein complex or within a given nano-environment. To illustrate this complexity empirically, we developed a protocol to analyze FRET among more than two fluorescent proteins (multi-FRET). In multi-FRET, we model FRET among more than two fluorophores as the sum of all possible pairwise interactions within the complex. We validated our assumption by demonstrating that FRET among pairs within a fluorescent triplet resembled FRET between each pair measured in the absence of the third fluorophore. FRET between two receptor chains increases with increasing FRET between the ligand-binding chain (e.g., IFN-γR1, IL-10R1 and IFN-λR1) and an acylated fluorescent protein that preferentially resides within subsections of the plasma membrane. The interaction of IL-10R2 with IFN-λR1 or IL-10R1 results in decreased FRET between IL-10R2 and the acylated fluorescent protein. Finally, we analyzed FRET among four fluorescent proteins to demonstrate that as FRET between IFN-γR1 and IFN-γR2 or between IFN-αR1 and IFN-αR2c increases, FRET among other pairs of proteins changes within each complex. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Heterotrimeric G protein beta1gamma2 subunits change orientation upon complex formation with G protein-coupled receptor kinase 2 (GRK2) on a model membrane.

    Science.gov (United States)

    Boughton, Andrew P; Yang, Pei; Tesmer, Valerie M; Ding, Bei; Tesmer, John J G; Chen, Zhan

    2011-09-13

    Few experimental techniques can assess the orientation of peripheral membrane proteins in their native environment. Sum Frequency Generation (SFG) vibrational spectroscopy was applied to study the formation of the complex between G protein-coupled receptor (GPCR) kinase 2 (GRK2) and heterotrimeric G protein β(1)γ(2) subunits (Gβγ) at a lipid bilayer, without any exogenous labels. The most likely membrane orientation of the GRK2-Gβγ complex differs from that predicted from the known protein crystal structure, and positions the predicted receptor docking site of GRK2 such that it would more optimally interact with GPCRs. Gβγ also appears to change its orientation after binding to GRK2. The developed methodology is widely applicable for the study of other membrane proteins in situ.

  8. Involvement of plasma membrane Ca2+ channels, IP3 receptors, and ryanodine receptors in the generation of spontaneous rhythmic contractions of the cricket lateral oviduct.

    Science.gov (United States)

    Tamashiro, Hirotake; Yoshino, Masami

    2014-12-01

    In the present study, the isolated cricket (Gryllus bimaculatus) lateral oviduct exhibited spontaneous rhythmic contractions (SRCs) with a frequency of 0.29±0.009 Hz (n=43) and an amplitude of 14.6±1.25 mg (n=29). SRCs completely disappeared following removal of extracellular Ca2+ using a solution containing 5mM EGTA. Application of the non-specific Ca2+ channel blockers Co2+, Ni2+, and Cd2+ also decreased both the frequency and amplitude of SRCs in dose-dependent manners,