Christiane Otto

Bayer HealthCare, Leverkusen, North Rhine-Westphalia, Germany

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Publications (32)157.96 Total impact

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    ABSTRACT: Endometriosis is a chronic, estrogen-dependent disease characterized by the presence of ectopic endometrium either in the pelvic cavity (endometriosis externa) or within the uterus (endometriosis interna, adenomyosis). Key symptoms are pelvic pain, dysmenorrhea and infertility. Established rodent animal models used for drug research in endometriosis have certain limitations. Since rodents do not menstruate, they cannot develop endometriosis externa spontaneously, but they suffer from endometriosis interna. There is growing evidence that human endometriosis externa and interna represent two faces of the same disease. Both are estrogen-dependent and respond to similar treatment paradigms. Here, we addressed the question whether a murine endometriosis interna model may also be suitable for the characterization of drugs employed in human endometriosis. We examined the effects of danazol, Faslodex and cetrorelix in SHN mice that developed endometriosis interna after pituitary grafting. The GnRH antagonist cetrorelix and the estrogen receptor antagonist Faslodex, which negatively interfered with estrogen-mediated signaling, completely inhibited endometriosis interna, whereas danazol, an androgenic progestin, showed significant therapeutic activity in the majority of SHN mice. We conclude that this murine endometriosis interna model may be a valuable complement to established endometriosis externa models to support drug research in human endometriosis.
    Experimental and therapeutic medicine 03/2012; 3(3):410-414. · 0.34 Impact Factor
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    ABSTRACT: Estrogen replacement is an effective therapy of postmenopausal symptoms such as hot flushes, bone loss, and vaginal dryness. Undesired estrogen effects are the stimulation of uterine and mammary gland epithelial cell proliferation as well as hepatic estrogenicity. In this study, we examined the influence of different estradiol release kinetics on tissue responsivity in ovariectomized (OVX) rats. Pulsed release kinetics was achieved by ip or sc administration of estradiol dissolved in physiological saline containing 10% ethanol (EtOH/NaCl) whereas continuous release kinetics was achieved by sc injection of estradiol dissolved in benzylbenzoate/ricinus oil (1+4, vol/vol). Initial 3-d experiments in OVX rats showed that pulsed ip estradiol administration had profoundly reduced stimulatory effects on the uterus and the liver compared with continuous release kinetics. On the other hand, both administration forms prevented severe vaginal atrophy. Based on these results, we compared the effects of pulsed (sc in EtOH/NaCl) vs. continuous (sc in benzylbenzoate/ricinus oil) estradiol release kinetics on bone, uterus, mammary gland, and liver in a 4-month study in OVX rats. Ovariectomy-induced bone loss was prevented by both administration regimes. However, pulsed estradiol resulted in lower uterine weight, reduced induction of hepatic gene expression, and reduced mammary epithelial hyperplasia relative to continuous estradiol exposure. We conclude that organ responsivity is influenced by different hormone release kinetics, a fact that might be exploited to reduce undesired estradiol effects in postmenopausal women.
    Endocrinology 02/2012; 153(4):1725-33. · 4.72 Impact Factor
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    ABSTRACT: G-protein-coupled receptor 30 (GPR30) has been reported to act as a membrane-bound estrogen receptor that is involved in the mediation of non-genomic estradiol signalling. In this study, we demonstrated that male, but not female, GPR30-deficient mice suffer from impaired left‑ventricular cardiac function. Left ventricles from male mutant mice were enlarged. There were no malformations in the valves or outflow tract of the heart. Both the contractility and relaxation capacity of the left ventricle were reduced, leading to increased left‑ventricular end-diastolic pressure in GPR30-deficient mice. In conclusion, our data support a role for GPR30 in the gender-specific aspects of heart failure.
    Molecular Medicine Reports 01/2011; 4(1):37-40. · 1.17 Impact Factor
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    ABSTRACT: In combined hormone replacement therapy (HRT) progestins are used to inhibit estradiol-activated uterine epithelial cell proliferation. In comparison to estradiol-only therapy, combined HRT leads to enhanced proliferation of mammary epithelial cells. In a quantitative mouse model, we assessed the balance between uterine and undesired mammary gland effects for two progestins that are widely used in HRT, progesterone and medroxyprogesterone acetate. Mice were ovariectomized and after 14 days they were treated subcutaneously with either vehicle, estradiol (100 ng) or estradiol plus increasing doses of progesterone or medroxyprogesterone acetate for three weeks. Measures for progestogenic mammary gland activity were stimulation of side-branching and stimulation of epithelial cell proliferation. Progestogenic activity in the uterus was assessed by measuring inhibition of estradiol-activated uterine epithelial cell proliferation. ED(50) and ID(50) values for the distinct readouts were obtained and dissociation factors for uterine versus mammary gland activity were calculated. MPA demonstrated uterine activity and mitogenic activity in the mammary gland at the same doses. In contrast, progesterone showed uterine activity at doses lower than those leading to significant stimulation of epithelial cell proliferation in the mammary gland. Progestins do not behave the same. Use of the natural hormone progesterone, but not MPA, in combined hormone therapy might offer a safety window between uterine effects and undesired proliferative activity in the mammary gland.
    Maturitas 04/2010; 65(4):386-91. · 2.84 Impact Factor
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    ABSTRACT: Repeated exposure to opiates leads to cellular and molecular changes and behavioral alterations reflecting a state of dependence. In noradrenergic neurons, cyclic AMP (cAMP)-dependent pathways are activated during opiate withdrawal, but their contribution to the activity of locus coeruleus noradrenergic neurons and behavioral manifestations remains controversial. Here, we test whether the cAMP-dependent transcription factors cAMP responsive element binding protein (CREB) and cAMP-responsive element modulator (CREM) in noradrenergic neurons control the cellular markers and the physical signs of morphine withdrawal in mice. Using the Cre/loxP system we ablated the Creb1 gene in noradrenergic neurons. To avoid adaptive effects because of compensatory up-regulation of CREM, we crossed the conditional Creb1 mutant mice with a Crem-/- line. We found that the enhanced expression of tyrosine hydroxylase normally observed during withdrawal was attenuated in CREB/CREM mutants. Moreover, the withdrawal-associated cellular hyperactivity and c-fos expression was blunted. In contrast, naloxone-precipitated withdrawal signs, such as jumping, paw tremor, tremor and mastication were preserved. We conclude by a specific genetic approach that the withdrawal-associated hyperexcitability of noradrenergic neurons depends on CREB/CREM activity in these neurons, but does not mediate several behavioral signs of morphine withdrawal.
    Journal of Neurochemistry 03/2010; 115(3):563-73. · 3.97 Impact Factor
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    ABSTRACT: The human estrogen receptors (hER) are members of the nuclear hormone receptor (NHR) superfamily and represent important drug targets for the pharmaceutical industry. Initially, ligand binding assays were used to identify novel ligands using receptors purified from native tissues. With the advent of molecular cloning techniques, cell-based transactivation assays have been the gold standard for many years of drug discovery. With the elucidation of the structural mechanisms underlying the activation of NHRs, cell-free assays with purified receptors have become important tools to directly assess different binding sites (e.g., the hormone binding site or the cofactor binding site). The available cell-free assays have so far facilitated the study of one binding site at a time. With the introduction of Terbium (Tb(3+))-based time-resolved fluorescence energy transfer (TR-FRET), it has become possible to measure 2 different interactions within 1 test tube in parallel. The authors have applied this technology to develop a dual readout system for the simultaneous monitoring of steroid hormone site binding and cofactor peptide recruitment. They took advantage of a commercially available fluorescent tracer as an indicator for classical steroid site binding and designed a novel peptide derived from the peroxisome proliferator-activated receptor gamma coactivator-1a (PGC1a) as an indicator for functional agonistic behavior of a test compound. The established assay is able to differentiate between agonists, antagonists, partial agonists, and compounds binding to the cofactor recruitment site. The IC(50) values obtained for a number of reference compounds in the multiplexed assay are in concordance with published data. The simple 1-step mix-and-measure protocol gives excellent quality and robustness and can be miniaturized to 5-microL volume.
    Journal of Biomolecular Screening 02/2010; 15(3):268-78. · 2.21 Impact Factor
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    ABSTRACT: The female sex hormone estradiol plays an important role in reproduction, mammary gland development, bone turnover, metabolism, and cardiovascular function. The effects of estradiol are mediated by two classical nuclear receptors, estrogen receptor alpha (ERalpha) and estrogen receptor beta (ERbeta). In 2005, G-protein-coupled receptor 30 (GPR30) was claimed to act as a non-classical estrogen receptor that was also activated by the ERalpha and ERbeta antagonists tamoxifen and fulvestrant (ICI 182780). Despite many conflicting results regarding the potential role of GPR30 as an estrogen receptor, the official nomenclature was changed to GPER (G-protein-coupled estrogen receptor). This review revisits the inconsistencies that still exist in the literature and focuses on selected publications that basically address the following two questions: what is the evidence for and against the hypothesis that GPR30 acts as an estrogen receptor? What is the potential in vivo role of GPR30? Thus, in the first part we focus on conflicting results from in vitro studies analysing the subcellular localization of GPR30, its ability to bind (or not to bind) estradiol and to signal (or not to signal) in response to estradiol. In the second part, we discuss the strengths and limitations of four available GPR30 mouse models. We elucidate the potential impact of different targeting strategies on phenotypic diversity.
    Steroids 01/2010; 75(8-9):603-10. · 2.80 Impact Factor
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    ABSTRACT: The majority of the biological effects of estrogens in the reproductive tract are mediated by estrogen receptor (ER)alpha, which regulates transcription by several mechanisms. Because the tissue-specific effects of some ERalpha ligands may be caused by tissue-specific transcriptional mechanisms of ERalpha, we aimed to identify the contribution of DNA recognition to these mechanisms in two clinically important target organs, namely uterus and liver. We used a genetic mouse model that dissects DNA binding-dependent vs. independent transcriptional regulation elicited by ERalpha. The EAAE mutant harbors amino acid exchanges at four positions of the DNA-binding domain (DBD) of ERalpha. This construct was knocked in the ERalpha gene locus to produce ERalpha((EAAE/EAAE)) mice devoid of a functional ERalpha DBD. The phenotype of the ERalpha((EAAE/EAAE)) mice resembles the general loss-of-function phenotype of alphaER knockout mutant mice with hypoplastic uteri, hemorrhagic ovaries, and impaired mammary gland development. In agreement with this phenotype, the expression pattern of the ERalpha((EAAE/EAAE)) mutant mice in liver obtained by genome-wide gene expression profiling supports the observation of a near-complete loss of estrogen-dependent gene regulation in comparison with the wild type. Further gene expression analyses to validate the results of the microarray data were performed by quantitative RT-PCR. The analyses indicate that both gene activation and repression by estrogen-bound ERalpha rely on an intact DBD in vivo.
    Molecular Endocrinology 08/2009; 23(10):1544-55. · 4.75 Impact Factor
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    ABSTRACT: Multiple reports implicated the function of G protein-coupled receptor (GPR)-30 with nongenomic effects of estrogen, suggesting that GPR30 might be a G-protein coupled estrogen receptor. However, the findings are controversial and the expression pattern of GPR30 on a cell type level as well as its function in vivo remains unclear. Therefore, the objective of this study was to identify cell types that express Gpr30 in vivo by analyzing a mutant mouse model that harbors a lacZ reporter (Gpr30-lacZ) in the Gpr30 locus leading to a partial deletion of the Gpr30 coding sequence. Using this strategy, we identified the following cell types expressing Gpr30: 1) an endothelial cell subpopulation in small arterial vessels of multiple tissues, 2) smooth muscle cells and pericytes in the brain, 3) gastric chief cells in the stomach, 4) neuronal subpopulations in the cortex as well as the polymorph layer of the dentate gyrus, 5) cell populations in the intermediate and anterior lobe of the pituitary gland, and 6) in the medulla of the adrenal gland. In further experiments, we aimed to decipher the function of Gpr30 by analyzing the phenotype of Gpr30-lacZ mice. The body weight as well as fat mass was unchanged in Gpr30-lacZ mice, even if fed with a high-fat diet. Flow cytometric analysis revealed lower frequencies of T cells in both sexes of Gpr30-lacZ mice. Within the T-cell cluster, the amount of CD62L-expressing cells was clearly reduced, suggesting an impaired production of T cells in the thymus of Gpr30-lacZ mice.
    Endocrinology 01/2009; 150(4):1722-30. · 4.72 Impact Factor
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    ABSTRACT: Glucocorticoid hormones (GCs) have been thought to determine the fate of chromaffin cells from sympathoadrenal progenitor cells. The analysis of mice carrying a germ line deletion of the glucocorticoid receptor (GR) gene has challenged these previous results because the embryonic development of adrenal chromaffin cells is largely unaltered. In the present study, we have analyzed the role of GC-dependent signaling in the postnatal development of adrenal chromaffin cells by conditional inactivation of the GR gene in cells expressing dopamine-beta-hydroxylase, an enzyme required for the synthesis of noradrenaline and adrenaline. These mutant mice are viable, allowing to study whether in the absence of GC signaling further development of the adrenal medulla is affected. Our analysis shows that the loss of GR leads not only to the loss of phenylethanolamine-N-methyl-transferase expression and, therefore, to inhibition of adrenaline synthesis, but also to a dramatic reduction in the number of adrenal chromaffin cells. We provide evidence that increased apoptotic cell death is the main consequence of GR loss. These findings define the essential role of GCs for survival of chromaffin cells and underscore the specific requirement of GCs for adrenergic chromaffin cell differentiation and maintenance.
    Endocrinology 12/2008; 150(4):1775-81. · 4.72 Impact Factor
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    ABSTRACT: The G protein-coupled receptor Gpr30 (Gper) was recently claimed to bind to estradiol and to activate cytoplasmic signal transduction pathways in response to estradiol. However, there are conflicting data regarding the role of Gpr30 as an estrogen receptor (ER): several laboratories were unable to demonstrate estradiol binding to GPR30 or estradiol-activated signal transduction in Gpr30-expressing cells. To clarify the potential role of Gpr30 as an ER, we generated Gpr30-deficient mice. Although Gpr30 was expressed in all reproductive organs, histopathological analysis did not reveal any abnormalities in these organs in Gpr30-deficient mice. Mutant male and female mice were as fertile as their wild-type littermates, indicating normal function of the hypothalamic-pituitary-gonadal axis. Moreover, we analyzed estrogenic responses in two major estradiol target organs, the uterus and the mammary gland. For that purpose, we examined different readout paradigms such as morphological measures, cellular proliferation, and target gene expression. Our data demonstrate that in vivo Gpr30 is dispensable for the mediation of estradiol effects in reproductive organs. These results are in clear contrast to the phenotype of mice lacking the classic ER alpha (Esr1) or aromatase (Cyp19a1). We conclude that the perception of Gpr30 (based on homology related to peptide receptors) as an ER might be premature and has to be reconsidered.
    Biology of Reproduction 10/2008; 80(1):34-41. · 4.03 Impact Factor
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    ABSTRACT: Estrogen receptor (ER) ligands that are able to prevent postmenopausal bone loss, but have reduced activity in the uterus and the mammary gland might be of great value for hormone therapy. It is well established that the classical ER can activate genomic as well as nongenomic signal transduction pathways. In this study, we analyse the in vivo behaviour of ER ligands that stimulate nongenomic ER effects to the same extent as estradiol, but show clearly reduced activation of genomic ER effects in vitro. Using different readout parameters such as morphological changes, cellular proliferation, and target gene induction, we are able to demonstrate that ER ligands with reduced genomic activity in vitro show a better dissociation of bone versus uterine and mammary gland effects than estradiol that stimulates genomic and nongenomic effects to the same extent. We conclude that pathway-selective ER ligands may represent an interesting option for hormone therapy.
    The Journal of Steroid Biochemistry and Molecular Biology 08/2008; 111(1-2):95-100. · 3.98 Impact Factor
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    ABSTRACT: The classical estrogen receptor (ER) mediates genomic as well as rapid nongenomic estradiol responses. In case of genomic responses, the ER acts as a ligand-dependent transcription factor that regulates gene expression in estrogen target tissues. In contrast, nongenomic effects are initiated at the plasma membrane and lead to rapid activation of cytoplasmic signal transduction pathways. Recently, an orphan G protein-coupled receptor, GPR30, has been claimed to bind to and to signal in response to estradiol. GPR30 therefore might mediate some of the nongenomic estradiol effects. The present study was performed to clarify the controversy about the subcellular localization of GPR30 and to gain insight into the in vivo function of this receptor. In transiently transfected cells as well as cells endogenously expressing GPR30, we confirmed that the receptor localized to the endoplasmic reticulum. However, using radioactive estradiol, we observed only saturable, specific binding to the classical ER but not to GPR30. Estradiol stimulation of cells expressing GPR30 had no impact on intracellular cAMP or calcium levels. To elucidate the physiological role of GPR30, we performed in vivo experiments with estradiol and G1, a compound that has been claimed to act as selective GPR30 agonist. In two classical estrogen target organs, the uterus and the mammary gland, G1 did not show any estrogenic effect. Taken together, we draw the conclusion that GPR30 is still an orphan receptor.
    Endocrinology 07/2008; 149(10):4846-56. · 4.72 Impact Factor
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    ABSTRACT: The role of progestins in combined hormone therapy is the inhibition of uterine epithelial cell proliferation. The Women's Health Initiative study provided evidence for an increased risk of breast cancer in women treated with conjugated equine estrogens plus the synthetic progestin medroxyprogesterone acetate (MPA), compared with conjugated equine estrogens-only treatment. These findings continue to be discussed, and it remains to be clarified whether the results obtained for MPA in the Women's Health Initiative study are directly applicable to other progestins used in hormone therapy. In this study we compared in a mouse model the effects of the synthetic progestins, MPA, and drospirenone in two major target organs: the uterus and mammary gland. As quantitative measures of progestin activity, we analyzed maintenance of pregnancy, ductal side branching in the mammary gland, and proliferation of mammary and uterine epithelial cells as well as target gene induction in both organs. The outcome of this study is that not all synthetic progestins exhibit the same effects. MPA demonstrated uterine activity and mitogenic activity in the mammary gland at the same doses. In contrast, drospirenone behaved similarly to the natural hormone, progesterone, and exhibited uterine activity at doses lower than those leading to considerable proliferative effects in the mammary gland. We hypothesize that the safety of combined hormone therapy in postmenopausal women may be associated with a dissociation between the uterine and mammary gland activities of the progestin component.
    Endocrinology 05/2008; 149(8):3952-9. · 4.72 Impact Factor
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    ABSTRACT: The cyclic-AMP response element-binding (CREB) protein family of transcription factors plays a crucial role in supporting the survival of neurons. However, a cell-autonomous role has not been addressed in vivo. To investigate the cell-specific role of CREB, we used as a model developing sympathetic neurons, whose survival in vitro is dependent on CREB activity. We generated mice lacking CREB in noradrenergic (NA) and adrenergic neurons and compared them with the phenotype of the germline CREB mutant. Whereas the germline CREB mutant revealed increased apoptosis of NA neurons and misplacement of sympathetic precursors, the NA neuron-specific mutation unexpectedly led to reduced levels of caspase-3-dependent apoptosis in sympathetic ganglia during the period of naturally occurring neuronal death. A reduced level of p75 neurotrophin receptor expression in the absence of CREB was shown to be responsible. Thus, our analysis indicates that the activity of cell-autonomous pro-survival signalling is operative in developing sympathetic neurons in the absence of CREB.
    Development 06/2007; 134(9):1663-70. · 6.21 Impact Factor
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    ABSTRACT: Besides of its functional role in the nervous system, the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) is involved in the regulation of cardiovascular function. Therefore, PACAP is a potent vasodilator in several vascular beds, including the renal vasculature. Because the kidney expresses both PACAP and PACAP-binding sites, it was speculated that PACAP might regulate cardiovascular function by direct vascular effects and indirectly by regulating renin release from the kidneys. PACAP (1-27) stimulated renin secretion from isolated perfused kidneys of rats 4.9-fold with a half-maximum concentration of 1.9 nmol/L. In addition, PACAP stimulated renin release and enhanced membrane capacitance of isolated juxtaglomerular cells, indicating a direct stimulation of exocytotic events. The effect of PACAP on renin release was mediated by the specific PACAP receptors (PAC1), because PACAP (1-27) applied in concentrations in the physiologic range (10 and 100 pmol/L) did not enhance renin release from isolated kidneys of PAC1 receptor knockout mice (PAC1-/-), whereas it stimulated renin release 1.38- and 2.5-fold in kidneys from wild-type mice. Moreover, plasma renin concentration was significantly lower in PAC1-/- compared with their wild-type littermates under control conditions as well as under a low- or high-salt diet and under treatment with the angiotensin-converting enzyme inhibitor ramipril, whereas no differences in plasma renin concentration between the genotypes were detectable after water deprivation. These data show that PACAP acting on PAC1 receptors potently stimulates renin release, serving as a tonic enhancer of the renin system in vivo.
    Journal of the American Society of Nephrology 05/2007; 18(4):1150-6. · 8.99 Impact Factor
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    ABSTRACT: Postmenopausal women that still have an uterus and suffer from hot flushes are treated with combinations of estrogens and progestins. Whereas estrogens are indispensable for treating postmenopausal symptoms, progestins are added to counteract the proliferative activity of estrogens on uterine epithelial cells. However, in the mammary gland, progestins, given together with estrogens, stimulate the proliferation of mammary epithelial cells. Therefore, progestins with reduced proliferative activity in the mammary gland would be of advantage for hormone therapy of postmenopausal women. In order to identify progestins with better tissue-selectivity, we exploited the activation of different signal transduction pathways by the classical progesterone receptor. We demonstrated that progestins with reduced non-genomic versus genomic activity in vitro show a better dissociation of uterine versus mammary gland effects in vivo than medroxyprogesterone acetate (MPA), a synthetic progestin that is widely used in hormone therapy.
    Ernst Schering Foundation symposium proceedings. 02/2007;
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    ABSTRACT: Different molecular mechanisms mediate the diverse biological effects of estrogens. The classical genomic mechanism is based on the function of the ER as a ligand-dependent transcription factor that binds to estrogen-response elements (EREs) in promoters of target genes to initiate gene expression. These direct genomic effects play a prominent role in the regulation of reproductive function. In contrast, nongenomic effects mediated by the classical ER have been demonstrated to activate PI3K, leading to the activation of endothelial NOS (eNOS) and hence vasorelaxation. Pathway-selective ER ligands might represent a novel option for hormone replacement therapy. Here we describe the identification and in vitro characterization of tool compounds that bind the ER reasonably well but exhibit low transcriptional activity on ERE-driven promoters. However, these compounds behave as potent stimulators of PI3K/Akt activation in vitro and lead to aortic vessel relaxation, a mechanism that is thought to be driven by nongenomic ER action. In a second set of experiments, we analyze how the in vitro pathway selectivity translates into the in vivo situation. We examine our tool compounds in comparison to estradiol and estren in the following paradigms: bone protection, uterine growth assays, and mammary gland assays.
    Ernst Schering Foundation symposium proceedings. 02/2006;
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    ABSTRACT: Sympathetic neurons are generated through a succession of differentiation steps that initially lead to noradrenergic neurons innervating different peripheral target tissues. Specific targets, like sweat glands in rodent footpads, induce a change from noradrenergic to cholinergic transmitter phenotype. Here, we show that cytokines acting through the gp 130 receptor are present in sweat glands. Selective elimination of the gp 130 receptor in sympathetic neurons prevents the acquisition of cholinergic and peptidergic features (VAChT, ChT1, VIP) without affecting other properties of sweat gland innervation. The vast majority of cholinergic neurons in the stellate ganglion, generated postnatally, are absent in gp 130-deficient mice. These results demonstrate an essential role of gp 130-signaling in the target-dependent specification of the cholinergic neurotransmitter phenotype.
    Development 02/2006; 133(1):141-50. · 6.21 Impact Factor
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    ABSTRACT: Estrogen receptors (ERs) stimulate genomic effects by acting as nuclear transcription factors as well as non-genomic effects by activating distinct cytoplasmic protein kinase cascades. Non-genomic effects have been implicated in numerous cellular processes, such as proliferation, differentiation, apoptosis and vasorelaxation. To exploit non-genomic effects mediated by ERalpha for novel hormone replacement regimens, we screened a focused library of steroid receptor ligands to identify compounds exhibiting properties different from estradiol, i.e. substances that selectively stimulate non-genomic signal transduction pathways while exhibiting low genomic activities. Treatment of breast cancer cells and osteosarcoma cells with estradiol, estren, substance A and substance B led to non-genomic activation of Akt (protein kinase B) and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling cascades mediated by Src (Rous Sarcoma Virus, non-receptor tyrosine kinase) and phosphatidylinositol-3-kinase (PI3K) stimulation. Such compounds leading to prominent Akt/ERK activation but exhibiting only weak genomic properties were applied in vasorelaxation assays, modeling physiological non-genomic ER responses. As expected from PI3K and Src activation data, substances were as effective as estradiol in mediating vasorelaxation. We assume that these pathway-selective estrogen receptor ligands may serve as potent lead structures for novel hormone replacement strategies exhibiting lesser side effects than the existing treatment paradigms.
    The Journal of Steroid Biochemistry and Molecular Biology 02/2006; 98(1):25-35. · 3.98 Impact Factor

Publication Stats

1k Citations
157.96 Total Impact Points

Institutions

  • 2006–2012
    • Bayer HealthCare
      Leverkusen, North Rhine-Westphalia, Germany
    • Paul-Ehrlich-Institut
      Langen, Hesse, Germany
  • 1997–2008
    • German Cancer Research Center
      • Division of Molecular Biology of the Cell II
      Heidelberg, Baden-Wuerttemberg, Germany
  • 2001
    • University Pompeu Fabra
      Barcino, Catalonia, Spain
  • 1999
    • Leibniz Institute for Neurobiology
      Magdeburg, Saxony-Anhalt, Germany